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Takeda, Y.; Kimura, F.; Takasawa, S. Possible Molecular Mechanisms of Hypertension in SAS. Encyclopedia. Available online: https://encyclopedia.pub/entry/54567 (accessed on 05 July 2024).
Takeda Y, Kimura F, Takasawa S. Possible Molecular Mechanisms of Hypertension in SAS. Encyclopedia. Available at: https://encyclopedia.pub/entry/54567. Accessed July 05, 2024.
Takeda, Yoshinori, Fuminori Kimura, Shin Takasawa. "Possible Molecular Mechanisms of Hypertension in SAS" Encyclopedia, https://encyclopedia.pub/entry/54567 (accessed July 05, 2024).
Takeda, Y., Kimura, F., & Takasawa, S. (2024, January 31). Possible Molecular Mechanisms of Hypertension in SAS. In Encyclopedia. https://encyclopedia.pub/entry/54567
Takeda, Yoshinori, et al. "Possible Molecular Mechanisms of Hypertension in SAS." Encyclopedia. Web. 31 January, 2024.
Possible Molecular Mechanisms of Hypertension in SAS
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Intermittent hypoxia (IH) is a central characteristic of sleep apnea syndrome (SAS), and it subjects cells in the body to repetitive apnea, chronic hypoxia, oxygen desaturation, and hypercapnia. Since SAS is linked to various serious cardiovascular complications, especially hypertension, many studies have been conducted to elucidate the mechanism of hypertension induced by SAS/IH. Hypertension in SAS is associated with numerous cardiovascular disorders. As hypertension is the most common complication of SAS, cell and animal models to study SAS/IH have developed and provided lots of hints for elucidating the molecular mechanisms of hypertension induced by IH. However, the detailed mechanisms are obscure and under investigation.

sleep apnea syndrome intermittent hypoxia hypertension reactive oxygen species hypoxia-inducible factors

1. Introduction

Intermittent hypoxia (IH) is a condition of repeated hypoxia and re-oxygenation that is typical of sleep apnea syndrome (SAS). SAS typically refers to a collection of conditions characterized by regular pauses in breathing or reduced breathing during sleep. Patients with this condition encounter airway blockage, a lack of oxygen, excessive carbon dioxide, and interrupted sleep due to awakening when there is insufficient oxygen. Approximately 1 billion adults aged between 30 and 69 years are projected to be affected by SAS [1]. SAS is linked to several complications and afflicts many patients. Some of those complications include obesity [2][3], type 2 diabetes [4][5][6][7], dyslipidemia [8][9], dementia [10][11], mood disorders [12], and, especially, hypertension [13][14][15].
Hypertension is the most frequent and important complication of SAS [16], with a prevalence ranging from 30% to 60% [17]. Hypertension in SAS is associated with numerous cardiovascular disorders, including coronary artery disease, stroke, arrhythmias, peripheral artery disease, and heart failure [18][19][20][21]. However, the correlation between SAS and cardiovascular disease is poorly understood due to the complexity of patient studies, which are influenced by factors such as the duration of the disease and the presence of other health conditions. Fletcher et al. proposed the concept that subjecting rodents to cyclical hypoxia would accurately replicate the hypoxemia encountered by patients with SAS [22]. The animals in this model experienced an increase in their blood pressure, which was proportional to the increase observed in patients with SAS [23][24]. The IH model replicates the physiological increase in blood pressure observed in SAS by simulating hypoxic conditions. It is known that the IH model adequately represents cardiorespiratory responses in SAS compared to the continuous hypoxia model [25]. Several studies have been undertaken to elucidate the underlying mechanism of hypertension in patients with SAS using various models.

2. Reactive Oxygen Species (ROS)

ROS refer to unstable and reactive forms of oxygen derivatives that are generated as a result of regular metabolic processes [26][27]. ROS generation is a major cellular mechanism underlying the effects of IH. Several studies have described that the ROS levels were increased in patients with SAS [25][28][29]. It has also been documented that nasal continuous positive airway pressure (CPAP) therapy decreases the levels of the markers associated with oxidative stress [28][30]. The nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) family of enzymes (EC 1.6.3.1) catalyzes the production of superoxide free radicals by transferring one electron to oxygen from NADPH and generating ROS [31].
The xanthine oxidoreductase enzyme system, which consists of xanthine dehydrogenase (XDH) (EC 1.17.1.4) and xanthine oxidase (XO) (EC 1.17.3.2), is a significant contributor to cellular ROS production [32][33]. A study on rat pheochromocytoma PC-12 cell cultures revealed that IH induces the initial production of ROS by directly stimulating XO [34]. XO activation occurs before NOX2 activation, and it is induced by IH. The ROS produced by XO lead to an increase in the cytosolic calcium concentration and the translocation of the cytosolic subunits p47phox (also known as neutrophil cytosolic factor 1) and p67phox (also known as neutrophil cytosolic factor 2) of NOX to the plasma membrane. These subunits then interact with the catalytic subunit gp91phox of NOX2. Allopurinol (1H-Pyrazolo [3,4-d]pyrimidin-4-ol), an XO inhibitor, or genetic silencing of XO using small interfering RNA (siRNA) can prevent all of these effects [35].
The consequences of brief periods of IH exposure, lasting for 10 days, could be reversed within 10 days of re-oxygenation. However, the consequences of prolonged periods of IH exposure, lasting for 30 days, continue to persist even after 30 days of recovery under normal air conditions [36][37][38][39]. Epigenetic mechanisms are associated with gene regulation and long-term physiological changes. DNA methylation is an example of an epigenetic mechanism. DNA methylation is facilitated by enzymes called DNA methyltransferases (Dnmt1 (DNA cytosine-5 methyltransferase 1; EC 2.1.1.37), Dnmt3a (DNA cytosine-5 methyltransferase 3α; EC 2.1.1.37), and Dnmt3b (DNA cytosine-5 methyltransferase 3β; EC 2.1.1.37)) [40][41]. Rats that received prolonged IH exhibited an increased Dnmt enzyme activity and high levels of Dnmt 1, 3a, and 3b proteins, which corresponded to changes in their respective mRNA levels [36][37][38]. Elevated levels of Dnmt activity are linked to excessive DNA methylation of genes that encode antioxidant enzymes [36][37][38]. Additional examinations revealed that rats subjected to prolonged IH displayed hypermethylation of a solitary CpG dinucleotide near the transcription start site of the superoxide dismutase 2 (SOD-2; EC 1.15.1.1) gene [36][37][38]. In contrast, the effect of short-term IH on DNA methylation was negligible, indicating that only long-term IH triggered DNA methylation. Administering decitabine (Deoxycytidine, 5-aza-2′-deoxycytidine), a DNA methyltransferase inhibitor, to rats during prolonged IH exposure prevents DNA hypermethylation, restores the expression of antioxidant enzyme genes, balances ROS levels in the chemo reflex pathway, and halts the development of hypertension [36][37][38]. These studies indicate that the continuous inhibition of antioxidant enzyme genes such as SOD, catalase (EC 1.11.1.6), and glutathione peroxidase (EC 1.11.1.9) through DNA methylation results in a sustained increase in ROS levels. This ultimately leads to chronic hypertension in rats that have been subjected to long-term IH treatment.

3. Hypoxia-Inducible Factors (HIFs)

Hypoxia-inducible factors (HIFs) act as primary controllers that ensure the balance of oxygen levels in all cells of the body by managing the supply and demand of oxygen [39][40][42]. The HIF family of transcription factors regulates the activation of various genes in hypoxic conditions. HIF-1 is composed of two subunits, an oxygen-sensitive inducible factor (HIF-1α) and the constitutive HIF-1β (also known as AhR nuclear translocator (ARNT)). The HIF-1α subunits undergo hydroxylation, ubiquitination, and proteasomal degradation in the presence of oxygen, but they accumulate quickly when oxygen is scarce. In the absence of oxygen, hydroxylation is suppressed, leading to the accumulation of HIF-1α. HIF-1α then combines with HIF-1β, attaches to hypoxia response elements, and triggers the activation of numerous target genes through transcription [42][43]. The molecular mechanism of HIF-1α upregulation during IH was investigated by Yuan et al. [44]. The process involves both an increase in the synthesis of HIF-1α through the mammalian target of rapamycin (mTOR) during re-oxygenation and a decrease in the degradation of HIF-1α through hydroxylase during hypoxia. Mice with HIF-1α heterozygosity that were treated with IH showed a significant lack of elevated levels of ROS [45]. In experiments with cell cultures subjected to IH, the increase in ROS production by NOX has been noted to result in the accumulation of HIF-1α [44]. Furthermore, exposure to IH leads to a decrease in the levels of antioxidants, such as SOD-2 (manganese-dependent superoxide dismutase; EC 1.15.1.1), while also increasing the levels of pro-oxidants, such as NOX [44][46]. Nanduri et al. suggested that the activation of NOX transcription induced by IH requires the simultaneous activation of HIF-1 through lysine demethylases known as the Jumonji-C (JmjC) family of lysine demethylases (JmjC-KDMs) (KDM2-8) [47]. The activation of HIF-1α transcription due to IH is dependent on the recruitment of p300 through Ca2+/calmodulin-dependent protein kinase (Cam kinase) II (EC 2.1.11.17) [48].
Prabhakar et al. suggested that IH upregulates HIF-1α but downregulates HIF-2α [49]. The α subunit of HIF-2α, which is regulated by O2, is commonly known as endothelial Per-Arnt-Sim (PAS) domain protein-1 (EPAS1) and belongs to the HIF family [50]. HIF-2α shares an 80% sequence similarity with HIF-1α and exhibits interaction with HIF-1β [51]. Similar to HIF-1α, a prolonged lack of oxygen causes an increase in HIF-2α levels, which then triggers the activation of vascular endothelial growth factor (VEGF) through transcription [52]. The downregulation of HIF-2α in response to IH is mediated by calcium signaling. In comparison to the increase in HIF-1α, studies have demonstrated that IH decreases the levels of HIF-2α protein by activating calpains, which are Ca2+-activated non-lysosomal cysteine proteases (EC 3.4.22.52/EC 3.4.22.53) that facilitate the degradation of HIF [46]. HIF-2α regulates the gene expression of various antioxidants, such as SOD-2 [46]. IH causes the degradation of HIF-2α, which leads to the inhibition of SOD-2 transcription and ultimately results in increased oxidative stress. ALLM (calpain inhibitor II; N-Acetyl-L-leucyl-L-leucyl-L-methioninal), a membrane-permeable strong calpain inhibitor, reverses the degradation of HIF-2α caused by IH, restores the activity of SOD-2, and prevents the increase in ROS [46]. These studies indicate that IH suppresses the activation of HIF-2α, resulting in elevated levels of ROS. These ROS, in combination with low oxygen levels, function together to stimulate the upregulation of HIF-1α and contribute to the development of hypertension caused by IH.

4. Endothelin 1 (ET-1)

Endothelin [53] is composed of 21 amino acids and has two disulfide bonds within the molecule. It is produced by processing a precursor consisting of 203 amino acids. In many mammals, there are three peptide isomers encoded by different genes: ET-1, ET-2, and ET-3 (ET-1: Cys-Ser-Cys-Ser-Ser-Leu-Met-Asp-Lys-Glu-Cys-Val-Tyr-Phe-Cys-His-Leu-Asp-Ile-Ile-Trp (Disulfide bonds between Cys1-Cys15 and Cys3-Cys11), ET-2: Cys-Ser-Cys-Ser-Ser-Trp-Leu-Asp-Lys-Glu-Cys-Val-Tyr-Phe-Cys-His-Leu-Asp-Ile-Ile-Trp (Disulfide bonds between Cys1-Cys15 and Cys3-Cys11), ET-3: Cys-Thr-Cys-Phe-Thr-Tyr-Lys-Asp-Lys-Glu-Cys-Val-Tyr-Tyr-Cys-His-Leu-Asp-Ile-Ile-Trp (Disulfide bonds between Cys1-Cys15 and Cys3-Cys11) in human endothelins). Endothelin has a transient vasodilatory effect followed by a sustained vasoconstrictive effect. However, the vasodilatory effect of ET-3 is very weak compared to the other two types. ET-1 functions through two receptors, namely the endothelin A (ETA) receptor and the endothelin B (ETB) receptor. Research using ETA receptor antagonists has indicated that ET-1 stimulates the ETA receptors. Prolonged exposure to low oxygen levels for 14 days lead to the upregulation of both the ETA receptor and preproendothelin, which is the precursor of ET-1. In addition, an increase in chemoreceptor activity corresponds to an increase in ET-1 and ETA expression [54]. After being subjected to IH for 4 days, cats experienced a 10-fold rise in the expression of ET-1. However, the administration of bosentan (4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl)pyrimidin-4-yl]benzenesulfonamide), a competitive and specific antagonist of ETA/ETB receptors in the endothelium and vascular smooth muscle, effectively prevented the IH-induced enhancement of both basal and hypoxic chemosensory responses [55].
HIF-1α may play a role in the development of hypertension caused by IH by increasing the expression of ET-1. The pre-pro ET-1 promoter contains hypoxia response elements, and hypoxia increases the transcription of pre-pro ET-1 by recruiting HIF-1α, activator protein 1 (AP-1), GATA-binding factor 2 (GATA-2), CAAT-binding factor (NF-1), and cyclic AMP response element-binding protein (CREB) (p300/CBP/CREB) to the transcriptome [56][57][58]. Furthermore, the increase in ET-1 due to IH relies on the existence of HIF-1 [59]. Consistent with the involvement of HIF-1α and ET-1 in IH, Belaidi et al. showed that HIF-1α and the endothelin system play significant roles in the development of myocardial infarction and hypertension in Wistar Kyoto hypertensive rats exposed to IH [60].

5. Inflammatory Molecules

Inflammation is a natural reaction of the immune system to tissue damage or invasion by pathogens [61]. The typical indicators of inflammation in the clinical setting include heightened blood circulation, the permeability of capillaries, the release of inflammatory substances, and the movement of white blood cells. The activation of molecules by the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) leads to the coordination of these processes. This activation triggers the release of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), chemokines and adhesion molecules [62]. Oxidative stress has the ability to cause the production and release of pro-inflammatory cytokines by controlling the transcriptional activity of certain transcription factors, such as NF-κB, AP-1, and HIF-1α [63]. NF-κB plays a crucial role in activating HIF-1α transcription and is essential for the buildup of HIF-1α under hypoxic conditions [64][65]. The HIF-1 gene contains a binding site for NF-κB in its proximal promoter region, and NF-κB seems to control the normal levels of HIF-1 gene expression [66]. It seems that the upregulation of HIF-1 transcription during hypoxia is dependent on NF-κB, and vice versa [66][67][68]. Alternatively, hypoxia can directly stimulate the NF-κB factor, leading to the production of pro-inflammatory cytokines through transcription [69]. The occurrence of alternating periods of low oxygen levels and subsequent re-oxygenation in individuals with SAS is linked to a rise in the levels of TNF-α, IL-6, and C-reactive protein in the bloodstream [70][71]. Furthermore, when faced with oxidative stress, HIF-1α triggers the movement of NF-κB to the nucleus, resulting in an increase in the synthesis of pro-inflammatory molecules, such as IL-1β, TNF-α, and ET-1 [72].
According to a study by Lam et al., it was found that after being exposed to IH for a period of 7 days, the levels of TNF-α, IL-1β, and inducible nitric oxide synthase (iNOS, NOS2; EC 1.14.13.39) mRNA increased in rats [73]. The systemic administration of the nonsteroidal anti-inflammatory drug (NSAID) ibuprofen (pyridin-2-ylmethyl(2RS)-2-[4-(2-methylpropyl)phenyl]propanoate) during IH did not decrease the enhanced chemosensory responses to hypoxia. However, it reduced the elevated chemosensory baseline and the elevated levels of pro-inflammatory cytokines [74]. The use of ibuprofen can prevent the development of high blood pressure caused by exposure to IH, as well as the adaptation of the respiratory system in rats. This suggests that ibuprofen may affect other components of the chemoreflex pathway [74]. Ibuprofen also inhibits the increase in the quantity of c-Fos (an AP-1 transcription factor subunit)-positive neurons in the caudal nucleus tractus solitarii (NTSs) of rats exposed to IH [74]. Snyder et al. discovered that IH for a week leads to oxidative stress and elevated levels of pro-inflammatory cytokines in brain regions linked to the initial phases of neurodegeneration, such as the substantia nigra and entorhinal cortex. However, these effects were not observed in the NTS and rostral ventrolateral medulla (RVLM) regions [75]. Oyarce and Iturriaga discovered that the mRNA levels of IL-1β, IL-6, and TNF-α were increased in the NTS of rats with hypertension following 21 days of IH [76]. These results indicate that the presence of pro-inflammatory cytokines in the NTS may play a role in sustaining hypertension. This is supported by the fact that IH leads to an increase in blood pressure within 3–4 days in conscious rats [77].

6. Renin–Angiotensin System (RAS)

The RAS has been shown to elevate ROS levels and plays a role in the development of hypertension caused by IH and SAS [78][79][80][81]. Angiotensin II (ANG II), the primary hormone responsible for the actions of RAS, affects both the peripheral and central systems, which can increase sympathetic activity and play a role in the development of hypertension [82]. Patients with SAS experience RAS activation, similar to rats that have been exposed to IH [78][83]. The activation of the carotid body and the exaggerated sympathetic reflexes caused by IH may lead to increased sympathetic nerve activity. This increase could potentially activate the peripheral RAS [84].
Glomus cells, which are contained in the carotid body, possess a pathway that can produce ANG II independently from renin [85][86]. When ANG II is continuously applied, it briefly increases the local firing of carotid afferents. However, when applied at discrete intervals, it leads to a long-lasting increase in baseline sensory nerve activity [87]. The application of serotonin (5-hydroxytryptamine [5-HT]) also produced the same phenomenon [88]. Both serotonin and ANG II work by stimulating the activity of NOX2, which generates ROS. The repeated activation of the glomus cells through ANG II or 5-HT during IH leads to a long-lasting increase in baseline sensory nerve activity and leads to heightened basal and chemoreflex stimulation. This may contribute to the maintenance of elevated mean arterial pressure observed in patients with SAS. Furthermore, ANG II inhibits the baroreflex [89], which may also contribute to the pathogenesis of IH-induced hypertension. The activation of the peripheral RAS could potentially trigger RAS activation in the brain [82]. The angiotensin receptor antagonist, losartan, can block or prevent IH-induced hypertension when administered either peripherally or centrally, indicating that both the peripheral and central RAS are involved in the pathogenesis of this type of hypertension [90][91][92][93]. Similar to ET-1, Lam et al. have demonstrated that ANG II increased the sensitivity of the carotid body to chemical stimuli, specifically within the carotid body itself, rather than due to changes in arterial pressure or blood flow [85]. ANG II increased carotid sinus nerve activity during in vitro carotid body preparation. Angiotensinogen is converted into ANG II by an angiotensin-converting enzyme (ACE; EC 3.4.15.1). Both protein and mRNA levels of angiotensinogen were detected in glomus cells. Similar to ET-1, chronic hypoxia increases the production of Ang II type 1 (AT1) receptors in the carotid body at the transcriptional and post-transcriptional levels [94]. Furthermore, blocking the AT1 receptors prevented the IH-induced increase in ROS production. This suggests that ANG II may enhance the chemoreceptor function. Shimoura et al. proposed that IH leads to a gradual activation of the RAS, which in turn stimulates a certain level of central AT1 receptor signaling. This signaling threshold is believed to have a permissive role in the initiation of a long-lasting increase in baseline sensory nerve activity [95]. Shell et al. suggested that injections of short hairpin RNA (shRNA) against AT1a into the median preoptic nucleus (MnPO) inhibited the IH-associated elevation in mRNA. Injections of shRNA prevented the sustained component of hypertension during normoxia, and reduced the levels of circulating advanced oxidation protein products, which are indicators of oxidative stress. This indicates that AT1 receptors in the MnPO contribute to the sustained increase in blood pressure during IH [96].
Renin (angiotensinogenase; EC 3.4.23.15) is considered the main factor that influences the RAS. Renin speeds up the RAS process by catalyzing the conversion of angiotensinogen into angiotensin I [97]. Renin is produced and released in the juxtaglomerular (JG) cells found in the afferent arteriole of the glomerulus in the kidney. Furthermore, the cluster of differentiation 38 (CD38)-cyclic ADP-ribose (cADPR; 1-β-D-ribofuranosyl-adenosine 5′-[trihydrogen diphosphate])-mediated signaling pathway has been proposed to have a function in regulating the synthesis and/or secretion of renin [98]. cADPR acts as a secondary messenger that triggers the release of calcium ions from the endoplasmic reticulum through ryanodine receptors (RyRs) [99][100][101][102][103]. CD38 is a type II glycoprotein that produces cADPR from NAD+ (ADP-ribosyl cyclase; EC 3.2.2.6) [104][105][106][107]. The expression of renin in As4.1 cells, a mouse prototype of juxtaglomerular (JG) cells, is influenced by the CD38-cADPR-mediated signaling pathway [108].

7. Catecholamine

Catecholamines also play a role in regulating blood pressure [109][110]. Researchersexamined the expression of enzymes involved in catecholamine production in both human and mouse neuroblastoma cells. Catecholamine-producing mouse Neuro-2a and human NB-1 neuroblastoma cells were used to prepare the cellular RNA. Cells were exposed to IH for 24 h, which is known to produce catecholamines. The levels of catecholamine biosynthesis enzymes, tyrosine hydroxylase (TH; EC 1.14.16.2), L-3,4-dihydroxyphenylalanine (DOPA) decarboxylase (DDC; EC 4.1.1.48), dopamine β-hydroxylase (DBH; EC 1.14.17.1), and phenylethanolamine N-methyltransferase (PNMT; EC 2.1.1.28) mRNAs were measured using a real-time reverse transcription polymerase chain reaction (RT-PCR). The real-time RT-PCR showed that exposure to IH led to a significant increase in the expression levels of DBH and PNMT mRNA levels in NB-1 and Neuro-2a cells. Immunoblot analyses revealed that IH significantly enhanced the expression of DBH and PNMT in NB-1 cells. The promoter assays using firefly luciferase as a reporter showed that the transcription of the DBH and PNMT genes in response to IH was not responsible for regulating their expressions. In relation to the mechanism involving miRNAs, the levels of miR-375, which was identified using the MicroRNA.org program as targeting both DBH and PNMT mRNAs, were measured using real-time RT-PCR in cells treated with IH. The level of miR-375 was significantly reduced compared to that in cells treated with normoxia. The increase in DBH and PNMT caused by IH was reversed when the miR-375 mimic was introduced to cells, but was not affected by the introduction of the non-specific control RNA for the miR-375 mimic. These findings suggest that IH promotes an increase in DBH and PNMT levels by preventing the degradation of DBH and PNMT mRNAs, which is normally mediated by miR-375 [111]. Hence, it can be concluded that the upregulated expression of DBH and PNMT in the neural cells of the adrenal medulla in patients with SAS may lead to high blood pressure. Additionally, miR-375 may play an important role in controlling the gene expression of DBH and PNMT. IH in patients with SAS and experimental models has been found to cause an increase in catecholamine synthesis, the secretion of catecholamines, and the upregulation of the PNMT gene, as reported in multiple studies [112][113]. Under hypoxic conditions, the secretion of catecholamines from neuronal and adrenal chromaffin cells is increased. This increase in secretion is observed both in laboratory settings (in vitro) and in living organisms (in vivo) and is accompanied by an upregulation of gene expression related to catecholamine production [114][115][116].

8. Cardiovascular Factors for Hypertension in IH

Vascular function assessments are helpful for a better understanding of the pathophysiological associations between vascular dysfunction and cardiac diseases, which could cause hypertension. Kyotani et al. isolated and cultured rat primary vascular smooth muscle cells and exposed them to IH. They found that IH increased vascular smooth muscle cell proliferation by upregulating the epidermal growth factor (EGF) family (epiregulin (EREG), amphiregulin, and neuregulin-1) and their erbB2 receptor (CD340) [117]. They also discovered that IH markedly elevated the expression of IL-6 and EREG in SV40-immortalized human coronary artery smooth muscle cells. Furthermore, the addition of IL-6 to the coronary artery smooth muscle cells induced EREG expression. These findings indicate that IL-6 may have a crucial role in EREG upregulation due to IH and, consequently, SAS-related atherosclerosis [117].
Regenerating gene (Reg) family proteins [118] and hepatocyte growth factor (Hgf) work as growth and anti-apoptotic factors in several tissues, such as pancreatic β-cells [119][120][121], the periosteum [122], and intestinal epithelial cells [118]. researchers found a significant increase in the mRNA levels of regenerating gene IV (Reg IV) and Hgf in rat H9c2 and mouse P19.CL6 cardiomyocytes that occurred due to IH. However, the promoter activities of these genes did not increase. researchers searched miRs against Reg IV and Hgf mRNAs, revealing that the rat and mouse mRNAs contain a potential target sequence for miR-499. The level of miR-499 in cardiomyocytes treated with IH was notably reduced compared to cells treated with normoxia. The P19.CL6 cells were transfected with an miR-499 mimic and a non-specific control RNA (miR-499 mimic NC). The upregulation of genes induced by IH was canceled by introducing the miR-499, but not by the miR-499 mimic NC. The findings suggest that IH stress leads to the suppression of miR-499 in cardiomyocytes, subsequently elevating the expression of Reg IV and Hgf mRNAs. This molecular response may contribute to the cardioprotective effects observed in patients with SAS [123].
The CD38-cADPR signaling system was originally found in glucose-induced insulin secretion from pancreatic β-cells [99][100][107]. Subsequently, it became clear that the CD38-cADPR signaling system is important for cardiac functions [124][125]. researchers found that the mRNA levels of Cd38, Ryr2 (cardiac-type ryanodine receptor), and FK506-binding protein 12.6 (Fkbp12.6; cADPR receptor) [107], essential components of RyR2 in H9c2 and P19.CL6 cardiomyocytes, were notably reduced due to IH, while the promoter activities of these genes remained unaffected. On the other hand, IH-treated cardiomyocytes exhibited an elevation in the expression of the phosphatase and tensin homolog deleted from chromosome 10 (Pten). Small interfering RNA against Pten (siPten) and a non-specific control RNA were introduced into the H9c2 cells. The reduction in Cd38, Ryr2, and Fkbp12.6 induced by IH was negated by the introduction of the siPten, but not by the control RNA. In addition, researchers added 3-deaza-cADPR [126], a cell-permeable cADPR agonist, into an H9c2 cell culture medium, followed by subjecting the cells to normoxia or IH for 24 h. After exposure to IH, the mRNA levels of Cd38, Ryr2, and Fkbp12.6 were assessed. It was found that the IH-induced reduction in the mRNA levels of Cd38, Ryr2, and Fkbp12.6 were mitigated by the introduction of 3-deaza-cADPR. This indicates that the IH-induced decrease in these mRNA levels may be attributed to the downregulation of the Cd38–cADPR-mediated signaling pathway. These results suggest that IH stress increases Pten expression in cardiomyocytes, reducing the mRNA levels of Cd38, Ryr2, and Fkbp12.6, leading to impaired cardiomyocyte function in patients with sleep apnea syndrome [127].
Vascular endothelial dysfunction, the earliest predictor of the subsequent development of cardiovascular diseases and hypertension [128], has been observed in patients with SAS. However, the specific mechanism through which IH induces endothelial complications remains unclear. Recently, researchers exposed vascular endothelial cells (human HUEhT-1 and mouse UV2) to IH, analyzed their gene expression, and found that IH exposure increased the expression of intercellular adhesion molecule 1 (Icam-1/CD54), a cell surface glycoprotein known as an adhesion receptor that directs leukocytes from circulation to sites of inflammation, and endothelial cell-specific molecule 1 (Esm1/Endocan). Icam-1 is present at minimal levels in immune cells, endothelial cells, and epithelial cells, but its expression is recognized to increase in reaction to inflammatory stimuli. The primary focus of research on Icam-1 has been its role in facilitating the trans-endothelial migration of leucocytes. Icam-1 is known to modulate the rolling and adhesion of leucocytes to the vessel wall, as well as to facilitate their passage through the endothelial layer. Esm1/Endocan is a proteoglycan associated with endothelial cells and is increased in response to proangiogenic molecules and pro-inflammatory cytokine stimulation. Esm1 is regarded as a novel biomarker with relevance to both tissue and blood, as it served as an indicator of endothelial activation and dysfunction.

9. Pro-Inflammatory/Inflammatory Cytokines

Several pro-inflammatory/inflammatory markers, including IL-1β, IL-6, IL-8, IL-17, IL-23, interferon-γ, CXCL10, and TNF-α, were found to be elevated in SAS patients with hypertension [129]. Most recently, researchers found that IH upregulated IL-1β, IL-6, and IL-8 in human monocytes through an miR-mediated mechanism. IL-1β induced type 2 NOS in pancreatic β-cells that exerted inhibitory and cytotoxic effects on insulin-producing pancreatic β-cells [130], which initiates or worsens diabetes. IL-6 induced EREG in coronary artery smooth muscle cells [117] to induce atherosclerosis. IL-8 was reported to be induced by IH in skeletal muscle cells to induce and worsen insulin resistance [131]. Therefore, the increases in pro-inflammatory and inflammatory cytokines such as IL-1β, IL-6, and IL-8 in monocytes lead to systemic inflammation and worsen metabolic syndrome, including hypertension in SAS patients.

References

  1. Benjafield, A.V.; Ayas, N.T.; Eastwood, P.R.; Heinzer, R.; Ip, M.S.M.; Morrell, M.J.; Nunez, C.M.; Patel, S.R.; Penzel, T.; Pépin, J.L.; et al. Estimation of the global prevalence and burden of obstructive sleep apnoea: A literature-based analysis. Lancet Respir. Med. 2019, 7, 687–698.
  2. Lee, J.H.; Cho, J. Sleep and obesity. Sleep Med. Clin. 2022, 17, 111–116.
  3. Bonsignore, M.R. Obesity and obstructive sleep apnea. Handb. Exp. Pharmacol. 2022, 274, 181–201.
  4. Ota, H.; Tamaki, S.; Itaya-Hironaka, A.; Yamauchi, A.; Sakuramoto-Tsuchida, S.; Morioka, T.; Takasawa, S.; Kimura, H. Attenuation of glucose-induced insulin secretion by intermittent hypoxia via down-regulation of CD38. Life Sci. 2012, 90, 206–211.
  5. Muraki, I.; Wada, H.; Tanigawa, T. Sleep apnea and type 2 diabetes. J. Diabetes Investig. 2018, 9, 991–997.
  6. Paschou, S.A.; Bletsa, E.; Saltiki, K.; Kazakou, P.; Kantreva, K.; Katsaounou, P.; Rovina, N.; Trakada, G.; Bakakos, P.; Vlachopoulos, C.V.; et al. Sleep apnea and cardiovascular risk in patients with prediabetes and Type 2 diabetes. Nutrients 2022, 14, 4989.
  7. Uchiyama, T.; Ota, H.; Itaya-Hironaka, A.; Shobatake, R.; Yamauchi, A.; Sakuramoto-Tsuchida, S.; Makino, M.; Kimura, H.; Takeda, M.; Ohbayashi, C.; et al. Up-regulation of selenoprotein P and HIP/PAP mRNAs in hepatocytes by intermittent hypoxia via down-regulation of miR-203. Biochem. Biophys. Rep. 2017, 11, 130–137.
  8. Barros, D.; García-Río, F. Obstructive sleep apnea and dyslipidemia: From animal models to clinical evidence. Sleep 2019, 42, zsy236.
  9. Popadic, V.; Brajkovic, M.; Klasnja, S.; Milic, N.; Rajovic, N.; Lisulov, D.P.; Divac, A.; Ivankovic, T.; Manojlovic, A.; Nikolic, N.; et al. Correlation of dyslipidemia and inflammation with obstructive sleep apnea severity. Front. Pharmacol. 2022, 13, 897279.
  10. Kang, J.; Tian, Z.; Wei, J.; Mu, Z.; Liang, J.; Li, M. Association between obstructive sleep apnea and Alzheimer’s disease-related blood and cerebrospinal fluid biomarkers: A meta-analysis. J. Clin. Neurosci. 2022, 102, 87–94.
  11. Mohammadi, I.; Adibparsa, M.; Najafi, A.; Sehat, M.S.; Sadeghi, M. A systematic review with meta-analysis to assess Alzheimer’s disease biomarkers in adults with or without obstructive sleep apnoea. Int. Orthod. 2023, 21, 100814.
  12. Maniaci, A.; Ferlito, S.; Lechien, J.R.; Di Luca, M.; Lannella, G.; Cammaroto, G. Anxiety, depression and sleepiness in OSA patients treated with barbed reposition pharyngoplasty: A prospective study. Eur. Arch. Otorhinolaryngol. 2022, 279, 4189–4198.
  13. Yuan, F.; Zhang, S.; Liu, X.; Liu, Y. Correlation between obstructive sleep apnea hypopnea syndrome and hypertension: A systematic review and meta-analysis. Ann. Palliat. Med. 2021, 10, 12251–12261.
  14. Seravalle, G.; Grassi, G. Sleep apnea and hypertension. High Blood Press. Cardiovasc. Prev. 2022, 29, 23–31.
  15. Brown, J.; Yazdi, F.; Jodari-Karimi, M.; Owen, J.G.; Reisin, E. Obstructive sleep apnea and hypertension: Updates to a critical relationship. Curr. Hypertens. Rep. 2022, 24, 173–184.
  16. Kanclerska, J.; Szymańska-Chabowska, A.; Poręba, R.; Michałek-Zrąbkowska, M.; Lachowicz, G.; Mazur, G.; Martynowicz, H. A systematic review of publications on the associations between sleep architecture and arterial hypertension. Med. Sci. Monit. 2023, 29, e941066.
  17. Fletcher, E.C. The relationship between systemic hypertension and obstructive sleep apnea: Facts and theory. Am. J. Med. 1995, 98, 118–128.
  18. Hohl, M.; Linz, B.; Böhm, M.; Linz, D. Obstructive sleep apnea and atrial arrhythmogenesis. Curr. Cardiol. Rev. 2014, 10, 362–368.
  19. Hsu, H.C.; Chen, N.H.; Ho, W.J.; Lin, M.H. Factors associated with undiagnosed obstructive sleep apnoea among hypertensive patients: A multisite cross-sectional survey study in Taiwan. J. Clin. Nurs. 2018, 27, 1901–1912.
  20. Kuniyoshi, F.H.; Pusalavidyasagar, S.; Singh, P.; Somers, V.K. Cardiovascular consequences of obstructive sleep apnoea. Indian J. Med. Res. 2010, 131, 196–205.
  21. Özlek, B.; Özlek, E.; Tekinalp, M.; Kahraman, S.; Zencirkiran Agus, H.; Başaran, Ö.; Kaya, B.C.; Rencüzoğulları, İ.; Mert, K.U.; Çakır, O.; et al. Comparison of clinical characteristics of patients with heart failure and preserved ejection fraction with atrial fibrillation versus sinus rhythm: Insights from the APOLLON registry. Turk. Kardiyol. Dern. Ars. 2020, 48, 234–245.
  22. Fletcher, E.C.; Lesske, J.; Qian, W.; Miller, C.C., 3rd; Unger, T. Repetitive, episodic hypoxia causes diurnal elevation of blood pressure in rats. Hypertension 1992, 19, 555–561.
  23. Foster, G.E.; Hanly, P.J.; Ahmed, S.B.; Beaudin, A.E.; Pialoux, V.; Poulin, M.J. Intermittent hypoxia increases arterial blood pressure in humans through a renin-angiotensin system-dependent mechanism. Hypertension 2010, 56, 369–377.
  24. Knight, W.D.; Little, J.T.; Carreno, F.R.; Toney, G.M.; Mifflin, S.W.; Cunningham, J.T. Chronic intermittent hypoxia increases blood pressure and expression of FosB/ΔFosB in central autonomic regions. Am. J. Physiol. Regul. Integr. Comp. Physiol. 2011, 301, R131–R139.
  25. Prabhakar, N.R.; Peng, Y.J.; Nanduri, J. Adaptive cardiorespiratory changes to chronic continuous and intermittent hypoxia. Handb. Clin. Neurol. 2022, 188, 103–123.
  26. Demirci-Çekiç, S.; Özkan, G.; Avan, A.N.; Uzunboy, S.; Çapanoğlu, E.; Apak, R. Biomarkers of oxidative stress and antioxidant defense. J. Pharm. Biomed. Anal. 2022, 209, 114477.
  27. Lin, S.; Ye, C.; Lin, Z.; Huang, L.; Li, D. Recent progress of near-infrared fluorescent probes in the determination of reactive oxygen species for disease diagnosis. Talanta 2024, 268, 125264.
  28. Lavie, L.; Vishnevsky, A.; Lavie, P. Evidence for lipid peroxidation in obstructive sleep apnea. Sleep 2004, 27, 123–128.
  29. Jordan, W.; Cohrs, S.; Degner, D.; Meier, A.; Rodenbeck, A.; Mayer, G.; Pilz, J.; Rüther, E.; Kornhuber, J.; Bleich, S. Evaluation of oxidative stress measurements in obstructive sleep apnea syndrome. J. Neural Transm. 2006, 113, 239–254.
  30. Meliante, P.G.; Zoccali, F.; Cascone, F.; Di Stefano, V.; Greco, A.; de Vincentiis, M.; Petrella, C.; Fiore, M.; Minni, A.; Barbato, C. Molecular pathology, oxidative stress, and biomarkers in obstructive sleep apnea. Int. J. Mol. Sci. 2023, 24, 5478.
  31. Pecchillo Cimmino, T.; Ammendola, R.; Cattaneo, F.; Esposito, G. NOX dependent ROS generation and cell metabolism. Int. J. Mol. Sci. 2023, 24, 2086.
  32. Nishino, T. The conversion of xanthine dehydrogenase to xanthine oxidase and the role of the enzyme in reperfusion injury. J. Biochem. 1994, 116, 1–6.
  33. Meneshian, A.; Bulkley, G.B. The physiology of endothelial xanthine oxidase: From urate catabolism to reperfusion injury to inflammatory signal transduction. Microcirculation 2002, 9, 161–175.
  34. Nanduri, J.; Vaddi, D.R.; Khan, S.A.; Wang, N.; Makerenko, V.; Prabhakar, N.R. Xanthine oxidase mediates hypoxia-inducible factor-2α degradation by intermittent hypoxia. PLoS ONE 2013, 8, e75838.
  35. Nanduri, J.; Vaddi, D.R.; Khan, S.A.; Wang, N.; Makarenko, V.; Semenza, G.L.; Prabhakar, N.R. HIF-1α activation by intermittent hypoxia requires NADPH oxidase stimulation by xanthine oxidase. PLoS ONE 2015, 10, e0119762.
  36. Nanduri, J.; Makarenko, V.; Reddy, V.D.; Yuan, G.; Pawar, A.; Wang, N.; Khan, S.A.; Zhang, X.; Kinsman, B.; Peng, Y.J.; et al. Epigenetic regulation of hypoxic sensing disrupts cardiorespiratory homeostasis. Proc. Natl. Acad. Sci. USA 2012, 109, 2515–2520.
  37. Nanduri, J.; Semenza, G.L.; Prabhakar, N.R. Epigenetic changes by DNA methylation in chronic and intermittent hypoxia. Am. J. Physiol. Lung Cell. Mol. Physiol. 2017, 313, L1096–L1100.
  38. Nanduri, J.; Peng, Y.J.; Wang, N.; Khan, S.A.; Semenza, G.L.; Kumar, G.K.; Prabhakar, N.R. Epigenetic regulation of redox state mediates persistent cardiorespiratory abnormalities after long-term intermittent hypoxia. J. Physiol. 2017, 595, 63–77.
  39. Nanduri, J.; Peng, Y.J.; Wang, N.; Khan, S.A.; Semenza, G.L.; Prabhakar, N.R. DNA methylation in the central and efferent limbs of the chemoreflex requires carotid body neural activity. J. Physiol. 2018, 596, 3087–3100.
  40. Morgan, A.E.; Davies, T.J.; Mc Auley, M.T. The role of DNA methylation in ageing and cancer. Proc. Nutr. Soc. 2018, 77, 412–422.
  41. Emon, I.M.; Al-Qazazi, R.; Rauh, M.J.; Archer, S.L. The role of clonal hematopoiesis of indeterminant potential and DNA (cytosine-5)-methyltransferase dysregulation in pulmonary arterial hypertension and other cardiovascular diseases. Cells 2023, 12, 2528.
  42. Kierans, S.J.; Taylor, C.T. Regulation of glycolysis by the hypoxia-inducible factor (HIF): Implications for cellular physiology. J. Physiol. 2021, 599, 23–37.
  43. Chen, H.; Ma, D.; Yue, F.; Qi, Y.; Dou, M.; Cui, L.; Xing, Y. The potential role of hypoxia-inducible factor-1 in the progression and therapy of central nervous system diseases. Curr. Neuropharmacol. 2022, 20, 1651–1666.
  44. Yuan, G.; Nanduri, J.; Khan, S.; Semenza, G.L.; Prabhakar, N.R. Induction of HIF-1α expression by intermittent hypoxia: Involvement of NADPH oxidase, Ca2+ signaling, prolyl hydroxylases, and mTOR. J. Cell. Physiol. 2008, 217, 674–685.
  45. Peng, Y.J.; Yuan, G.; Ramakrishnan, D.; Sharma, S.D.; Bosch-Marce, M.; Kumar, G.K.; Semenza, G.L.; Prabhakar, N.R. Heterozygous HIF-1α deficiency impairs carotid body-mediated systemic responses and reactive oxygen species generation in mice exposed to intermittent hypoxia. J. Physiol. 2006, 577, 705–716.
  46. Nanduri, J.; Wang, N.; Yuan, G.; Khan, S.A.; Souvannakitti, D.; Peng, Y.J.; Kumar, G.K.; Garcia, J.A.; Prabhakar, N.R. Intermittent hypoxia degrades HIF-2α via calpains resulting in oxidative stress: Implications for recurrent apnea-induced morbidities. Proc. Natl. Acad. Sci. USA 2009, 106, 1199–1204.
  47. Nanduri, J.; Wang, N.; Wang, B.L.; Prabhakar, N.R. Lysine demethylase KDM6B regulates HIF-1α-mediated systemic and cellular responses to intermittent hypoxia. Physiol. Genom. 2021, 53, 385–394.
  48. Yuan, G.; Nanduri, J.; Bhasker, C.R.; Semenza, G.L.; Prabhakar, N.R. Ca2+/calmodulin kinase-dependent activation of hypoxia inducible factor 1 transcriptional activity in cells subjected to intermittent hypoxia. J. Biol. Chem. 2005, 280, 4321–4328.
  49. Prabhakar, N.R.; Kumar, G.K.; Nanduri, J. Intermittent hypoxia augments acute hypoxic sensing via HIF-mediated ROS. Respir. Physiol. Neurobiol. 2010, 174, 230–234.
  50. Befani, C.; Liakos, P. The role of hypoxia-inducible factor-2 alpha in angiogenesis. J. Cell. Physiol. 2018, 233, 9087–9098.
  51. Ema, M.; Taya, S.; Yokotani, N.; Sogawa, K.; Matsuda, Y.; Fujii-Kuriyama, Y. A novel bHLH-PAS factor with close sequence similarity to hypoxia-inducible factor 1α regulates the VEGF expression and is potentially involved in lung and vascular development. Proc. Natl. Acad. Sci. USA 1997, 94, 4273–4278.
  52. Ajith, T.A. Current insights and future perspectives of hypoxia-inducible factor-targeted therapy in cancer. J. Basic Clin. Physiol. Pharmacol. 2018, 30, 11–18.
  53. Banecki, K.M.R.M.; Dora, K.A. Endothelin-1 in health and disease. Int. J. Mol. Sci. 2023, 24, 11295.
  54. Chen, J.; He, L.; Dinger, B.; Stensaas, L.; Fidone, S. Role of endothelin and endothelin A-type receptor in adaptation of the carotid body to chronic hypoxia. Am. J. Physiol. Lung Cell. Mol. Physiol. 2002, 282, L1314–L1323.
  55. Rey, S.; Del Rio, R.; Iturriaga, R. Contribution of endothelin-1 to the enhanced carotid body chemosensory responses induced by chronic intermittent hypoxia. Brain Res. 2006, 1086, 152–159.
  56. Hu, T.; Luan, R.; Zhang, H.; Lau, W.B.; Wang, Q.; Zhang, Y.; Wang, H.C.; Tao, L. Hydrogen peroxide enhances osteopontin expression and matrix metalloproteinase activity in aortic vascular smooth muscle cells. Clin. Exp. Pharmacol. Physiol. 2009, 36, 626–630.
  57. Minchenko, A.; Caro, J. Regulation of endothelin-1 gene expression in human microvascular endothelial cells by hypoxia and cobalt: Role of hypoxia responsive element. Mol. Cell. Biochem. 2000, 208, 53–62.
  58. Yamashita, K.; Discher, D.J.; Hu, J.; Bishopric, N.H.; Webster, K.A. Molecular regulation of the endothelin-1 gene by hypoxia. Contributions of hypoxia-inducible factor-1, activator protein-1, GATA-2, and p300/CBP. J. Biol. Chem. 2001, 276, 12645–12653.
  59. Lam, S.Y.; Tipoe, G.L.; Liong, E.C.; Fung, M.L. Hypoxia-inducible factor (HIF)-1α and endothelin-1 expression in the rat carotid body during intermittent hypoxia. Adv. Exp. Med. Biol. 2006, 580, 21–27.
  60. Belaidi, E.; Joyeux-Faure, M.; Ribuot, C.; Launois, S.H.; Levy, P.; Godin-Ribuot, D. Major role for hypoxia inducible factor-1 and the endothelin system in promoting myocardial infarction and hypertension in an animal model of obstructive sleep apnea. J. Am. Coll. Cardiol. 2009, 53, 1309–1317.
  61. Roe, K. An inflammation classification system using cytokine parameters. Scand. J. Immunol. 2021, 93, e12970.
  62. Shih, R.H.; Wang, C.Y.; Yang, C.M. NF-kappaB signaling pathways in neurological inflammation: A mini review. Front. Mol. Neurosci. 2015, 8, 77.
  63. Prabhakar, N.R.; Semenza, G.L. Oxygen sensing and homeostasis. Physiology 2015, 30, 340–348.
  64. Hocker, A.D.; Stokes, J.A.; Powell, F.L.; Huxtable, A.G. The impact of inflammation on respiratory plasticity. Exp. Neurol. 2017, 287, 243–253.
  65. Huang, Y.; Liu, Z.; Li, L.; Jiang, M.; Tang, Y.; Zhou, L.; Li, J.; Chen, Y. Sesamin inhibits hypoxia-stimulated angiogenesis via the NF-κB p65/HIF-1α/VEGFA signaling pathway in human colorectal cancer. Food Funct. 2022, 13, 8989–8997.
  66. Bonello, S.; Zähringer, C.; BelAiba, R.S.; Djordjevic, T.; Hess, J.; Michiels, C.; Kietzmann, T.; Görlach, A. Reactive oxygen species activate the HIF-1α promoter via a functional NFκB site. Arterioscler. Thromb. Vasc. Biol. 2007, 27, 755–761.
  67. Görlach, A.; Bonello, S. The cross-talk between NF-κB and HIF-1: Further evidence for a significant liaison. Biochem. J. 2008, 412, e17–e19.
  68. Rius, J.; Guma, M.; Schachtrup, C.; Akassoglou, K.; Zinkernagel, A.S.; Nizet, V.; Johnson, R.S.; Haddad, G.G.; Karin, M. NF-κB links innate immunity to the hypoxic response through transcriptional regulation of HIF-1α. Nature 2008, 453, 807–811.
  69. Eltzschig, H.K.; Carmeliet, P. Hypoxia and inflammation. N. Engl. J. Med. 2011, 364, 656–665.
  70. Meier-Ewert, H.K.; Ridker, P.M.; Rifai, N.; Regan, M.M.; Price, N.J.; Dinges, D.F.; Mullington, J.M. Effect of sleep loss on C-reactive protein, an inflammatory marker of cardiovascular risk. J. Am. Coll. Cardiol. 2004, 43, 678–683.
  71. Irwin, M.R.; Carrillo, C.; Olmstead, R. Sleep loss activates cellular markers of inflammation: Sex differences. Brain Behav. Immun. 2010, 24, 54–57.
  72. Chang, R.C.; Chiu, K.; Ho, Y.S.; So, K.F. Modulation of neuroimmune responses on glia in the central nervous system: Implication in therapeutic intervention against neuroinflammation. Cell. Mol. Immunol. 2009, 6, 317–726.
  73. Lam, S.Y.; Liu, Y.; Ng, K.M.; Lau, C.F.; Liong, E.C.; Tipoe, G.L.; Fung, M.L. Chronic intermittent hypoxia induces local inflammation of the rat carotid body via functional upregulation of proinflammatory cytokine pathways. Histochem. Cell Biol. 2012, 137, 303–317.
  74. Del Rio, R.; Moya, E.A.; Parga, M.J.; Madrid, C.; Iturriaga, R. Carotid body inflammation and cardiorespiratory alterations in intermittent hypoxia. Eur. Respir. J. 2012, 39, 1492–1500.
  75. Snyder, B.; Shell, B.; Cunningham, J.T.; Cunningham, R.L. Chronic intermittent hypoxia induces oxidative stress and inflammation in brain regions associated with early-stage neurodegeneration. Physiol. Rep. 2017, 5, e13258.
  76. Oyarce, M.P.; Iturriaga, R. Proinflammatory cytokines in the nucleus of the solitary tract of hypertensive rats exposed to chronic intermittent hypoxia. Adv. Exp. Med. Biol. 2018, 1071, 69–74.
  77. Del Rio, R.; Andrade, D.C.; Lucero, C.; Arias, P.; Iturriaga, R. Carotid body ablation abrogates hypertension and autonomic alterations induced by intermittent hypoxia in rats. Hypertension 2016, 68, 436–445.
  78. Dempsey, J.A.; Veasey, S.C.; Morgan, B.J.; O’Donnell, C.P. Pathophysiology of sleep apnea. Physiol. Rev. 2010, 90, 47–112.
  79. Guyenet, P.G. The sympathetic control of blood pressure. Nat. Rev. Neurosci. 2006, 7, 335–346.
  80. Shell, B.; Faulk, K.; Cunningham, J.T. Neural control of blood pressure in chronic intermittent hypoxia. Curr. Hypertens. Rep. 2016, 18, 19.
  81. Caputo, I.; Bertoldi, G.; Driussi, G.; Cacciapuoti, M.; Calò, L.A. The RAAS goodfellas in cardiovascular system. J. Clin. Med. 2023, 12, 6873.
  82. Grobe, J.L.; Xu, D.; Sigmund, C.D. An intracellular renin-angiotensin system in neurons: Fact, hypothesis, or fantasy. Physiology 2008, 23, 187–193.
  83. Saxena, A.; Little, J.T.; Nedungadi, T.P.; Cunningham, J.T. Angiotensin II type 1a receptors in subfornical organ contribute towards chronic intermittent hypoxia-associated sustained increase in mean arterial pressure. Am. J. Physiol. Heart Circ. Physiol. 2015, 308, H435–H446.
  84. Silva, A.Q.; Schreihofer, A.M. Altered sympathetic reflexes and vascular reactivity in rats after exposure to chronic intermittent hypoxia. J. Physiol. 2011, 589, 1463–1476.
  85. Lam, S.Y.; Leung, P.S. A locally generated angiotensin system in rat carotid body. Regul. Pept. 2002, 107, 97–103.
  86. Leung, P.S.; Lam, S.Y.; Fung, M.L. Chronic hypoxia upregulates the expression and function of AT1 receptor in rat carotid body. J. Endocrinol. 2000, 167, 517–524.
  87. Peng, Y.J.; Raghuraman, G.; Khan, S.A.; Kumar, G.K.; Prabhakar, N.R. Angiotensin II evokes sensory long-term facilitation of the carotid body via NADPH oxidase. J. Appl. Physiol. 2011, 111, 964–970.
  88. Peng, Y.J.; Yuan, G.; Jacono, F.J.; Kumar, G.K.; Prabhakar, N.R. 5-HT evokes sensory long-term facilitation of rodent carotid body via activation of NADPH oxidase. J. Physiol. 2006, 576, 289–295.
  89. Brooks, V.L.; Ell, K.R.; Wright, R.M. Pressure-independent baroreflex resetting produced by chronic infusion of angiotensin II in rabbits. Am. J. Physiol. 1993, 265, H1275–H1282.
  90. Marcus, N.J.; Li, Y.L.; Bird, C.E.; Schultz, H.D.; Morgan, B.J. Chronic intermittent hypoxia augments chemoreflex control of sympathetic activity: Role of the angiotensin II type 1 receptor. Respir. Physiol. Neurobiol. 2010, 171, 36–45.
  91. da Silva, A.Q.; Fontes, M.A.; Kanagy, N.L. Chronic infusion of angiotensin receptor antagonists in the hypothalamic paraventricular nucleus prevents hypertension in a rat model of sleep apnea. Brain Res. 2011, 1368, 231–238.
  92. Fletcher, E.C.; Orolinova, N.; Bader, M. Blood pressure response to chronic episodic hypoxia: The renin-angiotensin system. J. Appl. Physiol. 2002, 92, 627–633.
  93. Knight, W.D.; Saxena, A.; Shell, B.; Nedungadi, T.P.; Mifflin, S.W.; Cunningham, J.T. Central losartan attenuates increases in arterial pressure and expression of FosB/ΔFosB along the autonomic axis associated with chronic intermittent hypoxia. Am. J. Physiol. Regul. Integr. Comp. Physiol. 2013, 305, R1051–R1058.
  94. Lin, L.; Finn, L.; Zhang, J.; Young, T.; Mignot, E. Angiotensin-converting enzyme, sleep-disordered breathing, and hypertension. Am. J. Respir. Crit. Care Med. 2004, 170, 1349–1353.
  95. Shimoura, C.G.; Andrade, M.A.; Toney, G.M. Central AT1 receptor signaling by circulating angiotensin II is permissive to acute intermittent hypoxia-induced sympathetic neuroplasticity. J. Appl. Physiol. 2020, 128, 1329–1337.
  96. Shell, B.; Farmer, G.E.; Nedungadi, T.P.; Wang, L.A.; Marciante, A.B.; Snyder, B.; Cunningham, R.L.; Cunningham, J.T. Angiotensin type 1a receptors in the median preoptic nucleus support intermittent hypoxia-induced hypertension. Am. J. Physiol. Regul. Integr. Comp. Physiol. 2019, 316, R651–R665.
  97. Kim, H.L. Arterial stiffness and hypertension. Clin. Hypertens. 2023, 29, 31.
  98. Xiong, J.; Xia, M.; Yi, F.; Abais, J.M.; Li, N.; Boini, K.M.; Li, P.L. Regulation of renin release via cyclic ADP-ribose-mediated signaling: Evidence from mice lacking CD38 gene. Cell. Physiol. Biochem. 2013, 31, 44–55.
  99. Takasawa, S.; Nata, K.; Yonekura, H.; Okamoto, H. Cyclic ADP-ribose in insulin secretion from pancreatic β cells. Science 1993, 259, 370–373.
  100. Takasawa, S.; Akiyama, T.; Nata, K.; Kuroki, M.; Tohgo, A.; Noguchi, N.; Kobayashi, S.; Kato, I.; Katada, T.; Okamoto, H. Cyclic ADP-ribose and inositol 1,4,5-trisphosphate as alternate second messengers for intracellular Ca2+ mobilization in normal and diabetic β-cells. J. Biol. Chem. 1998, 273, 2497–2500.
  101. Takasawa, S.; Kuroki, M.; Nata, K.; Noguchi, N.; Ikeda, T.; Yamauchi, A.; Ota, H.; Itaya-Hironaka, A.; Sakuramoto-Tsuchida, S.; Takahashi, I.; et al. A novel ryanodine receptor expressed in pancreatic islets by alternative splicing from type 2 ryanodine receptor gene. Biochem. Biophys. Res. Commun. 2010, 397, 140–145.
  102. Galione, A.; Lee, H.C.; Busa, W.B. Ca2+-induced Ca2+ release in sea urchin egg homogenates: Modulation by cyclic ADP-ribose. Science 1991, 253, 1143–1146.
  103. Galione, A. Cyclic ADP-ribose: A new way to control calcium. Science 1993, 259, 325–326.
  104. Takasawa, S.; Tohgo, A.; Noguchi, N.; Koguma, T.; Nata, K.; Sugimoto, T.; Yonekura, H.; Okamoto, H. Synthesis and hydrolysis of cyclic ADP-ribose by human leukocyte antigen CD38 and inhibition of the hydrolysis by ATP. J. Biol. Chem. 1993, 268, 26052–26054.
  105. Howard, M.; Grimaldi, J.C.; Bazan, J.F.; Lund, F.E.; Santos-Argumedo, L.; Parkhouse, R.M.; Walseth, T.F.; Lee, H.C. Formation and hydrolysis of cyclic ADP-ribose catalyzed by lymphocyte antigen CD38. Science 1993, 262, 1056–1059.
  106. Zocchi, E.; Franco, L.; Guida, L.; Benatti, U.; Bargellesi, A.; Malavasi, F.; Lee, H.C.; De Flora, A. A single protein immunologically identified as CD38 displays NAD+ glycohydrolase, ADP-ribosyl cyclase and cyclic ADP-ribose hydrolase activities at the outer surface of human erythrocytes. Biochem. Biophys. Res. Commun. 1993, 196, 1459–1465.
  107. Takasawa, S. CD38-cyclic ADP-ribose signal system in physiology, biochemistry, and pathophysiology. Int. J. Mol. Sci. 2022, 23, 4306.
  108. Yi, F.; Zhang, A.Y.; Li, N.; Zhang, F.; Xia, M.; Li, P.L. Role of cyclic ADP-ribose-Ca2+ signaling in mediating renin production and release in As4.1 cells. Cell. Physiol. Biochem. 2007, 19, 293–302.
  109. Channer, B.; Matt, S.M.; Nickoloff-Bybel, E.A.; Pappa, V.; Agarwal, Y.; Wickman, J.; Gaskill, P.J. Dopamine, immunity, and disease. Pharmacol. Rev. 2023, 75, 62–158.
  110. Elam, M.; Grassi, G. Adrenaline and hypertension: New evidence for a guilty verdict? J. Hypertens. 2000, 18, 675–677.
  111. Takasawa, S.; Shobatake, R.; Takeda, Y.; Uchiyama, T.; Yamauchi, A.; Makino, M.; Sakuramoto-Tsuchida, S.; Asai, K.; Ota, H.; Itaya-Hironaka, A. Intermittent hypoxia increased the expression of DBH and PNMT in neuroblastoma cells via microRNA-375-mediated mechanism. Int. J. Mol. Sci. 2022, 23, 5868.
  112. Ziegler, M.G.; Nelesen, R.; Mills, P.; Ancoli-Israel, S.; Kennedy, B.; Dimsdale, J.E. Sleep apnea, norepinephrine-release rate, and daytime hypertension. Sleep 1997, 20, 224–231.
  113. Khurana, S.; Peng, S.; McDonald, E.; Yates, W.; Venkataraman, K.; Tai, T.C. Phenylethanolamine N-methyltransferase gene expression in PC12 cells exposed to intermittent hypoxia. Neurosci. Lett. 2018, 666, 169–174.
  114. Nurse, C.A.; Salman, S.; Scott, A.L. Hypoxia-regulated catecholamine secretion in chromaffin cells. Cell Tissue Res. 2018, 372, 433–441.
  115. Makarenko, V.V.; Peng, Y.J.; Khan, S.A.; Nanduri, J.; Fox, A.P.; Prabhakar, N.R. Long-term facilitation of catecholamine secretion from adrenal chromaffin cells of neonatal rats by chronic intermittent hypoxia. J. Neurophysiol. 2019, 122, 1874–1883.
  116. Gridina, A.; Su, X.; Khan, S.A.; Peng, Y.J.; Wang, B.; Nanduri, J.; Fox, A.P.; Prabhakar, N.R. Gaseous transmitter regulation of hypoxia-evoked catecholamine secretion from murine adrenal chromaffin cells. J. Neurophysiol. 2021, 125, 1533–1542.
  117. Kyotani, Y.; Takasawa, S.; Yoshizumi, M. Proliferative pathways of vascular smooth muscle cells by intermittent hypoxia. Int. J. Mol. Sci. 2019, 20, 2706.
  118. Takasawa, S. Regenerating gene (REG) product and its potential clinical usage. Exp. Opin. Ther. Tergets 2016, 20, 541–550.
  119. Kobayashi, S.; Akiyama, T.; Nata, K.; Abe, M.; Tajima, M.; Shervani, N.J.; Unno, M.; Matsuno, S.; Sasaki, H.; Takasawa, S.; et al. Identification of a receptor for reg (regenerating gene) protein, a pancreatic β-cell regeneration factor. J. Biol. Chem. 2000, 275, 10723–10726.
  120. Akiyama, T.; Takasawa, S.; Nata, K.; Kobayashi, S.; Abe, M.; Shervani, N.J.; Ikeda, T.; Nakagawa, K.; Unno, M.; Matsuno, S.; et al. Activation of Reg gene, a gene for insulin-producing β-cell regeneration: Poly(ADP-ribose) polymerase binds Reg promoter and regulates the transcription by autopoly(ADP-ribosyl)ation. Proc. Natl. Acad. Sci. USA 2001, 98, 48–53.
  121. Nakagawa, K.; Takasawa, S.; Nata, K.; Yamauchi, A.; Itaya-Hironaka, A.; Ota, H.; Yoshimoto, K.; Sakuramoto-Tsuchida, S.; Miyaoka, T.; Takeda, M.; et al. Prevention of Reg I-induced β-cell apoptosis by IL-6/dexamethasone through activation of HGF gene regulation. Biochim. Biophys. Acta 2013, 1833, 2988–2995.
  122. Tohma, Y.; Dohi, Y.; Shobatake, R.; Uchiyama, T.; Takeda, M.; Takasawa, S.; Tanaka, Y.; Ohgushi, H. Reg gene expression in periosteum after fracture and its in vitro induction triggered by IL-6. Int. J. Mol. Sci. 2017, 18, 2257.
  123. Takasawa, S.; Itaya-Hironaka, A.; Makino, M.; Yamauchi, A.; Sakuramoto-Tsuchida, S.; Uchiyama, T.; Shobatake, R.; Takeda, Y.; Ota, H. Upregulation of Reg IV and Hgf mRNAs by intermittent hypoxia via downregulation of microRNA-499 in cardiomyocytes. Int. J. Mol. Sci. 2022, 23, 12414.
  124. Mészáros, L.G.; Bak, J.; Chu, A. Cyclic ADP-ribose as an endogenous regulator of the non-skeletal type ryanodine receptor Ca2+ channel. Nature 1993, 364, 76–79.
  125. Yano, M.; Ono, K.; Ohkusa, T.; Suetsugu, M.; Kohno, M.; Hisaoka, T.; Kobayashi, S.; Hisamatsu, Y.; Yamamoto, T.; Kohno, M.; et al. Altered stoichiometry of FKBP12.6 versus ryanodine receptor as a cause of abnormal Ca2+ leak through ryanodine receptor in heart failure. Circulation 2000, 102, 2131–2136.
  126. Wong, L.; Aarhusm, R.; Lee, H.C.; Walseth, T.F. Cyclic 3-deaza-adenosine diphosphoribose: A potent and stable analog of cyclic ADP-ribose. Biochim. Biophys. Acta 1999, 1472, 555–564.
  127. Takasawa, S.; Makino, M.; Uchiyama, T.; Yamauchi, A.; Sakuramoto-Tsuchida, S.; Itaya-Hironaka, A.; Takeda, Y.; Asai, K.; Shobatake, R.; Ota, H. Downregulation of the Cd38-cyclic ADP-ribose signaling in cardiomyocytes by intermittent hypoxia via Pten upregulation. Int. J. Mol. Sci. 2022, 23, 8782.
  128. Yazan, S.; Karakurt, H.; Püşüroğlu, H. Relationship between obstructive sleep apnea severity and serum endocan levels in patients with hypertension. Tex. Heart Inst. J. 2023, 50, e217664.
  129. Deussen, A.; Kopaliani, I. Targeting inflammation in hypertension. Curr. Opin. Nephrol. Hypertens. 2023, 32, 111–117.
  130. Susick, L.; Veluthakal, R.; Suresh, M.V.; Hadden, T.; Kowluru, A. Regulatory roles for histone deacetylation in IL-β-induced nitric oxide release in pancreatic β-cells. J. Cell. Mol. Med. 2008, 12, 1571–1583.
  131. Takasawa, S.; Shobatake, R.; Itaya-Hironaka, A.; Makino, M.; Uchiyama, T.; Sakuramoto-Tsuchida, S.; Takeda, Y.; Ota, H.; Yamauchi, A. Upregulation of IL-8, osteonectin, and myonectin mRNAs by intermittent hypoxia via OCT1- and NRF2-mediated mechanisms in skeletal muscle cells. J. Cell. Mol. Med. 2022, 26, 6019–6031.
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