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Topic Review
Carbon Monoxide in Cardioprotection and Platelet
Nitric oxide (NO) and carbon monoxide (CO) represent a pair of biologically active gases with an increasingly well-defined range of effects on circulating platelets. These gases interact with platelets and cells in the vessels and heart and exert fundamentally similar biological effects, albeit through different mechanisms and with some peculiarity. Within the cardiovascular system, for example, the gases are predominantly vasodilators and exert antiaggregatory effects, and are protective against damage in myocardial ischemia-reperfusion injury. Differently from NO, only a limited number of studies have been carried out on CO effects on platelets and CO and cardioprotection.
  • 863
  • 04 Apr 2023
Topic Review
BKCa Channel Function in Cellular Membranes
Alterations in the activity of BKCa channels, responsible for the generation of the overall magnitude of Ca2+-activated K+ current at the whole-cell level, occur through allosteric mechanisms. The collaborative interplay between membrane depolarization and heightened intracellular Ca2+ ion concentrations collectively contribute to the activation of BKCa channels.
  • 862
  • 30 Jan 2024
Topic Review
The Gut Microbiota Function
The microbiota is known as the set of microorganisms residing in each ecosystem, with a symbiotic relationship and with adaptive properties and rapid renewal, forming a large metabolic unit. The intestinal microbiota is a set of microorganisms made up of approximately 100,000 million bacteria that live in people intestine. The microbiota is responsible, among other functions, for maintaining the well-being of the intestinal mucosa, helping digest food and converting harmful elements into less toxic substances.
  • 861
  • 17 Oct 2022
Topic Review
Sex-Related Differences in Neurodegeneration
Sex hormones and genes on the sex chromosomes are not only key factors in the regulation of sexual differentiation and reproduction but they are also deeply involved in brain homeostasis. Their action is crucial for the development of the brain, which presents different characteristics depending on the sex of individuals. The role of these players in the brain is fundamental in the maintenance of brain function during adulthood as well, thus being important also with respect to age-related neurodegenerative diseases. 
  • 847
  • 05 Jun 2023
Topic Review
Physiological Functions of Melatonin in Horticultural Plants
Melatonin, a hormone known for its role in regulating sleep–wake cycles in mammals, has been found to have diverse functions in horticultural plants. Research has revealed the involvement of melatonin in various physiological processes in plants, like regulation of growth and development, stress tolerance, and antioxidant defense. Melatonin can augment seed germination, roots, shoot growth, and biomass accumulation in horticultural crops. It also performs a vital role in regulating vegetative and reproductive growth stages, floral transition, and leaf senescence. Melatonin improves stress tolerance in crops by regulating root architecture, nutrient uptake, and ion transport.
  • 847
  • 20 Sep 2023
Topic Review
Matrix Metalloproteinases in Chronic Obstructive Pulmonary Disease
Matrix metalloproteinases (MMPs) are proteolytic enzymes that degrade proteins of the extracellular matrix and the basement membrane. Thus, these enzymes regulate airway remodeling, which is a major pathological feature of chronic obstructive pulmonary disease (COPD). Furthermore, proteolytic destruction in the lungs may lead to loss of elastin and the development of emphysema, which is associated with poor lung function in COPD patients.
  • 846
  • 10 Mar 2023
Topic Review
Impairment of Blood-Brain Barrier in Alzheimer’s Disease
Alzheimer’s disease (AD) is the most common neurodegenerative disorder and its prevalence is increasing. Very few drugs effectively reduce AD symptoms and thus, a better understanding of its pathophysiology is vital to design new effective schemes. Presymptomatic neuronal damage caused by the accumulation of Amyloid β peptide and Tau protein abnormalities remains a challenge, despite recent efforts in drug development. Importantly, therapeutic targets, biomarkers, and diagnostic techniques have emerged to detect and treat AD. Of note, the compromised blood-brain barrier (BBB) and peripheral inflammation in AD are becoming more evident, being harmful factors that contribute to the development of the disease. Perspectives from different pre-clinical and clinical studies link peripheral inflammation with the onset and progression of AD.
  • 845
  • 15 Sep 2022
Topic Review
Mammalian Autophagy Machinery and Autophagy-Related Genes
Physiologically, autophagy is an evolutionarily conserved and self-degradative process in cells. Autophagy carries out normal physiological roles throughout mammalian life. Accumulating evidence shows autophagy as a mechanism for cellular growth, development, differentiation, survival, and homeostasis.
  • 836
  • 15 May 2023
Topic Review
Oxygen Cascade from Atmosphere to Mitochondria
Hypoxia is a life-threatening challenge for about 1% of the world population and a contributor to high morbidity and mortality scores in patients affected by various cardiopulmonary, hematological, and circulatory diseases. In most cases, it is not hypoxia that generates diseases, but rather the attempts to adapt to the hypoxia condition. Thus, when adaptation to hypoxia becomes excessive, it translates into maladaptation. The oxygen cascade may represent a tool for understanding the genesis and the consequences of physiological and pathological hypoxia.
  • 834
  • 04 Sep 2023
Topic Review
O-GlcNAcylation in Renal (Patho)Physiology
O-GlcNAcylation is regulated by the enzymatic balance between O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) which add and remove GlcNAc residues on target proteins, respectively. This post-translational modification is essential for cellular physiology, and unbalanced protein O-GlcNAcylation is associated with several diseases. Here, we discuss aspects of protein O-GlcNAcylation in renal physiology and pathophysiology
  • 834
  • 26 Oct 2022
Topic Review
Hypothalamic Suprachiasmatic Nuclei
24-h rhythms in physiology and behaviour are organized by a body-wide network of endogenous circadian clocks. In mammals, a central pacemaker in the hypothalamic suprachiasmatic nucleus (SCN) integrates external light information to adapt cellular clocks in all tissues and organs to the external light-dark cycle.
  • 832
  • 13 Dec 2021
Topic Review
CCN5/WISP2 Gene Deficiency
CCN5/WISP2 is a matricellular protein, the expression of which is under the regulation of Wnt signaling and IGF-1. 
  • 831
  • 23 Dec 2021
Topic Review
Physiological Mental Workload Indicators
Mental workload (MWL), sometimes referred to as cognitive workload, is a dynamic concept that acquires different meanings depending on the outcome desired.  Physiological indicators of MWL have gained an immense amount of attention in several domains, considering their objective nature. The response of the human body to external sources of workloads can be effectively observed through physiological signal markers that are not heavily affected by subjective opinions. Overall, it can be considered an indirect measure that can be related to MWL and has a relatively quicker response to sudden shifts. Physiological processes that include heart activity, respiration, digestion, and sexual arousal are involuntarily regulated by the peripheral component of the autonomic nervous system. The autonomic nervous system has three distinct divisions, namely, the sympathetic (SNS), parasympathetic (PNS), and enteric. The activation of the SNS and PNS can be directly observed in HR and HRV variations. Some commonly used SNS- and PNS-related physiological indicators are heart rate (HR), heartrate variability (HRV), respiratory rate (RR), galvanic skin response (GSR), and electrodermal activity (EDA). Eye-related data such as pupil size are also a result of autonomic activity and have been an important component of MWL research, as visual and mental tasks are highly correlated. Previous research has suggested that an increase in the cognitive demand or an increase in the MWL can result in increased blood flow in the frontal cortex of the brain.
  • 829
  • 18 May 2023
Topic Review
Atrial Natriuretic Peptide Signaling in Uteroplacental Cells
Endometrial decidualization is a uterine process essential for spiral artery remodeling, embryo implantation, and trophoblast invasion. Defects in endometrial decidualization and spiral artery remodeling are important contributing factors in preeclampsia, a major disorder in pregnancy. Atrial natriuretic peptide (ANP) is a cardiac hormone that regulates blood volume and pressure. ANP is also generated in non-cardiac tissues, such as the uterus and placenta. In recent human genome-wide association studies, multiple loci with genes involved in natriuretic peptide signaling are associated with gestational hypertension and preeclampsia.
  • 829
  • 11 Aug 2023
Topic Review
Microbiota Short-Chain Fatty Acids Modulate Antioxidant Defences
Food nutrients play a key role in human metabolism and health via the modulation of multiple mechanisms, including energy metabolism, intestinal homeostasis, antioxidant homeostasis, and immune responses. The intestine is an essential organ involved in human nutrition, the metabolic activity of gut microbes is essential for maintaining host health, and alterations in its composition induce metabolic shifts that may have adverse effects. The consensus on microbiota-mediated healthy effects on the host is based on the microbe-induced biotransformation of food components into bioactive metabolites. Bioactive molecules exhibit, in combination with food components, the ability to modulate the metabolic pathways of the host or to modify the composition and metabolism of the microbiota. Studies indicated the efficacy of the carbohydrates accessible to the microbiota (MACs), polyphenols, and polyunsaturated fatty acids (PUFAs) in increasing the microbial population with the ability to yield biologically active metabolites (e.g., polyphenol metabolites, short-chain fatty acids (SCFAs)) capable of modulating redox homeostasis of the host.
  • 828
  • 16 Jun 2023
Topic Review
Insulin in the Striatum
Insulin crosses the blood–brain barrier to enter the brain from the periphery. In the brain, insulin has well-established actions as a satiation signal in the hypothalamus, as well as effects on feeding at the level of mesolimbic dopamine neurons in the midbrain. However, insulin also acts in the striatum, a forebrain region that is crucial for movement, mood and motivated behavior. The striatum shows abundant expression of insulin receptors (InsRs) throughout. These receptors are found on interneurons and striatal projections neurons, as well as on glial cells and dopamine axons.
  • 823
  • 30 Jun 2023
Topic Review
Exercise and Their Immunomodulation Effect
Depending on the intensity and volume, physical exercise can stimulate oxidative stress and muscle inflammation to generate muscle recovery. The practice of physical exercise is considered a potent immunomodulator, during physical exercise, both in trained and sedentary individuals, it is possible to observe a brief increase in the number of circulating leukocytes, which are mobilized from the lymphatic system, vessel walls, and spleen, indicating the ability of exercise to influence different cell compartments.
  • 822
  • 01 Mar 2023
Topic Review
Neuromuscular Activity during Cycling Performance
To determine the relationships between limiting factors and neuromuscular activity during a self-paced 20-km cycling time trial and evaluate the effect of environmental conditions on fatigue indices. Methods: Ten endurance-trained and heat-acclimated athletes performed in three conditions (ambient temperature, relative humidity): HUMID (30 °C, 90%), DRY (35 °C, 46%) and NEUTRAL (22 °C, 55%). Voluntary muscular contractions and electromagnetic stimulations were recorded before and after the time trials to assess fatigue. The data on performance, temperature, heat storage, electromyogram, heart rate and rating of perceived exertion data were analyzed. Results: Performance was impaired in DRY and HUMID compared with NEUTRAL environment (p < 0.05). The force developed by the vastus lateral muscle during stimulation of the femoral nerve remained unchanged across conditions. The percentage of integrated electromyogram activity, normalized by the value attained during the pre-trial maximal voluntary contraction, decreased significantly throughout the trial only in HUMID condition (p < 0.01). Neuromuscular activity in peripheral skeletal muscle started to fall from the 11th km in HUMID and the 15th km in DRY condition, although core temperature did not reach critical values. Conclusions: These alterations suggest that afferences from core/skin temperature regulate the central neural motor drive, reducing the active muscle recruited during prolonged exercise in the heat in order to prevent the system from hyperthermia. 
  • 819
  • 29 Mar 2022
Topic Review
Omics and Male Infertility
Male infertility is a multifaceted disorder affecting approximately 50% of male partners in infertile couples. Over the years, male infertility has been diagnosed mainly through semen analysis, hormone evaluations, medical records and physical examinations, which of course are fundamental, but yet inefficient, because 30% of male infertility cases remain idiopathic. This dilemmatic status of the unknown needs to be addressed with more sophisticated and result-driven technologies and/or techniques. Genetic alterations have been linked with male infertility, thereby unveiling the practicality of investigating this disorder from the “omics” perspective. Omics aims at analyzing the structure and functions of a whole constituent of a given biological function at different levels, including the molecular gene level (genomics), transcript level (transcriptomics), protein level (proteomics) and metabolites level (metabolomics).
  • 814
  • 08 Mar 2022
Topic Review
mTORC1 and Nutritional Interventions in Ageing
The effect of mTOR complex 1 (mTORC1) inhibitors in ageing has been a matter of scientific study since the 1990s. In fact, most initial efforts elucidating the beneficial effects of rapamycin have revealed its role in ageing, with Romero et al. describing in 1995 its effect in preventing reduced bone growth in aged rat. Since mTORC1 responds to nutritional availability, the effects of mTORC1 inhibition using specific inhibitors such as rapamycin or through nutritional interventions in ageing and health have been widely reviewed.
  • 811
  • 30 Sep 2022
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