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Topic Review
Lipoxidation End-Product Malondialdehyde-Lysine in Aging and Longevity
The nonenzymatic adduction of malondialdehyde (MDA) to the protein amino groups leads to the formation of malondialdehyde-lysine (MDALys). The degree of unsaturation of biological membranes and the intracellular oxidative conditions are the main factors that modulate MDALys formation. The low concentration of this modification in the different cellular components, found in a wide diversity of tissues and animal species, is indicative of the presence of a complex network of cellular protection mechanisms that avoid its cytotoxic effects. 
  • 809
  • 15 Nov 2023
Topic Review
Calcium and Autophagy in Alzheimer’s Disease
Alzheimer’s disease (AD) is an age-related brain disorder that causes progressive neurodegeneration predominantly in the cortical and hippocampal brain regions. Major hallmarks of AD are the progressive impairment of memory storage and accumulation of fibrillary amyloid plaques in patient’s brains. Autophagy is a process that maintains healthy cells, organelles, proteins, and nutrient homeostasis in living organisms. Three types of autophagy are observed in mammalian cells depending on the mode of substrate delivery: macroautophagy, chaperone-mediated autophagy, and microautophagy.
  • 808
  • 24 May 2023
Topic Review
Protein Misfolding in Pregnancy
Protein misfolding disorders are a group of diseases characterized by supra-physiologic accumulation and aggregation of pathogenic proteoforms resulting from improper protein folding and/or insufficiency in clearance mechanisms. Although these processes have been historically linked to neurodegenerative disorders, such as Alzheimer’s disease, evidence linking protein misfolding to other pathologies continues to emerge. Indeed, the deposition of toxic protein aggregates in the form of oligomers or large amyloid fibrils has been linked to type 2 diabetes, various types of cancer, and, in more recent years, to preeclampsia, a life-threatening pregnancy-specific disorder. While extensive physiological mechanisms are in place to maintain proteostasis, processes, such as aging, genetic factors, or environmental stress in the form of hypoxia, nutrient deprivation or xenobiotic exposures can induce failure in these systems. As such, pregnancy, a natural physical state that already places the maternal body under significant physiological stress, creates an environment with a lower threshold for aberrant aggregation. 
  • 806
  • 02 Apr 2024
Topic Review
Dopaminergic Modulation of Prefrontal Cortex Inhibition
The prefrontal cortex is the highest stage of integration in the mammalian brain. Its functions vary greatly, from working memory to decision-making, and are primarily related to higher cognitive functions. This explains the considerable effort devoted to investigating this area, revealing the complex molecular, cellular, and network organization, and the essential role of various regulatory controls. In particular, the dopaminergic modulation and the impact of local interneurons activity are critical for prefrontal cortex functioning, controlling the excitatory/inhibitory balance and the overall network processing. Here will focus on the dopaminergic modulation of GABAergic inhibition, which plays a significant role in shaping prefrontal cortex activity.
  • 804
  • 12 May 2023
Topic Review
Acute Psychosocial Stress Effects on Food Consumption
The most central physiological stress response is the activation of the hypothalamic-pituitary-adrenal (HPA) axis, which begins with the release of corticotrophin-releasing factor (CRF) from the hypothalamus. The physiological stress response can be dampened by eating, as the secretion of adrenocorticotropic hormone (ACTH) is reduced following consumption of food and the activation of the HPA axis is thereby attenuated.
  • 803
  • 27 Jun 2022
Topic Review
Association between Periodontitis and Peri-Implantitis
Dental implants to replace lost teeth are a common dentistry practice nowadays. Titanium dental implants display a high success rate and improved safety profile. Nevertheless, there is an increasing peri-implantitis (PI), an inflammatory disease associated with polymicrobial infection that adversely affects the hard and soft tissues around the implant. Studies have demonstrated that oral microbiota (microorganisms residing in the oral cavity collectively known as oral microbiota) associated with periodontitis (PE) is involved in the infections related to PI, indicating a common link between PE and PI.
  • 801
  • 16 Jan 2023
Topic Review
Single Cell Transcriptomics to Understand Hematopoietic Stem Cells
Aging leads to a decline in the functions of the hematopoietic and immune system, which in the elderly results in an increased risk of infection, poor vaccination efficacy, anemia and blood cancers. It is now well established that age-related dysfunction of the entire hematopoietic system originates from hematopoietic stem cells (HSCs), which lose their fitness over time. Single-cell transcriptomic technologies enable the uncovering and characterization of cellular heterogeneity and pave the way for studies aiming at understanding the origin and consequences of it. The hematopoietic system is in essence a very well adapted model system to benefit from this technological advance because it is characterized by different cellular states. Each cellular state, and its interconnection, may be defined by a specific location in the global transcriptional landscape sustained by a complex regulatory network. This transcriptomic signature is not fixed and evolved over time to give rise to less efficient hematopoietic stem cells (HSC), leading to a well-documented hematopoietic aging. 
  • 799
  • 18 Oct 2022
Topic Review
Oxidative Stress and Immune Response in Melanoma
Melanoma, a neoplasm arising from malignant transformation of melanocytes, is the most lethal form of skin cancer.
  • 798
  • 12 Jan 2023
Topic Review
Lipid-Based Antioxidant Systems in Photoreceptors and RPE Cells
The retina, a multi-layered nervous structure in the back of the eye, detects light stimuli via specialised primary sensory neurons, named after their morphologies as retinal rods and cones. Rods and cones in vitro may retain their ability to respond to light for several hours by generating an electrical response. However, their viability and long-term operation require the functional interaction with retinal pigment epithelial (RPE) cells and a vascular system with peculiar features, the choroidal capillaries (ChC), whose specific form and shape support its function.
  • 790
  • 20 Mar 2023
Topic Review
Oxidative Stress in Cirrhosis and Portal Hypertension
Oxidative stress is an imbalance between the production of reactive oxygen species (ROS) and the antioxidant system reducing its capability to detoxify ROS or repair the resulting damage, i.e., ROS overwhelms antioxidants. Oxidative stress is a key pathogenic factor in chronic liver injury of various etiologies, such as alcoholic liver disease.
  • 789
  • 07 Dec 2023
Topic Review
Hypothalamic Control of Circadian Homeostasis and Hormone Regulation
Hypothalamic hormone release functions through a cascade system induced by input received from higher brain centers responding to environmental information. These hormones travel through the hypothalamic-hypophyseal portal system to the pituitary to produce or inhibit hormones that are then transported throughout the body to interact with target organs.
  • 777
  • 02 Mar 2023
Topic Review
RBPs Associated with Cardiomyopathies
Cardiomyopathies are structural and functional abnormalities of the myocardium and represent a heterogenous group of cardiac disorders, including dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy (RCM), and arrhythmogenic cardiomyopathy (ACM). RNA-binding proteins (RBPs) are major regulators of gene expression at the post-transcriptional level and contribute to generating protein abundance and diversity within a cell.
  • 776
  • 22 Mar 2024
Topic Review
Potential Benefits and Risks of Statins
HMG-CoA (3-hydroxy-3-methyl-glutaryl-coenzyme A) reductase inhibitors, commonly known as statins, are the primary treatment choice for cardiovascular diseases, which stand as the leading global cause of mortality. Statins also offer various pleiotropic effects, including improved endothelial function, anti-inflammatory properties, reduced oxidative stress, anti-thrombotic effects, and the stabilization of atherosclerotic plaques. However, the usage of statins can be accompanied by a range of adverse effects, such as the development of type 2 diabetes mellitus, muscular symptoms, liver toxicity, kidney diseases, cataracts, hemorrhagic strokes, and psychiatric complications. These issues are referred to as statin-associated symptoms (SAS) and are relatively infrequent in clinical trials, making it challenging to attribute them to statin use definitively. Therefore, these symptoms can lead to significant problems, necessitating dose adjustments or discontinuation of statin therapy.
  • 771
  • 28 Feb 2024
Topic Review
Kinases/Protein Phosphatases in Signaling Pathways Activation
Optimizing physical training regimens to increase muscle aerobic capacity requires an understanding of the internal processes that occur during exercise that initiate subsequent adaptation. During exercise, muscle cells undergo a series of metabolic events that trigger downstream signaling pathways and induce the expression of many genes in working muscle fibers. There are a number of studies that show the dependence of changes in the activity of AMP-activated protein kinase (AMPK), one of the mediators of cellular signaling pathways, on the duration and intensity of single exercises. The activity of various AMPK isoforms can change in different directions, increasing for some isoforms and decreasing for others, depending on the intensity and duration of the load.
  • 769
  • 11 Jul 2023
Topic Review
Renal Sodium
Sodium retention is a well-documented consequence of many pathophysiological conditions, especially kidney disease, which is clinically recognized as an accumulation of edema.
  • 766
  • 14 Mar 2022
Topic Review
Mechanisms behind the Guar Drought Tolerance
Guar is an unpretentious plant and grows on both sandy and well-drained clay soils. Guar is self-pollinating with a negligible level of cross-pollination. The plants considerably vary in height (from 50 cm to 1.5 m). The stem is sturdy, becoming woody by the plant maturation. The main root is thick and tapering in its distal parts, deeply penetrating into the soil. Due to this, guar can perfectly sustain short-term drought. 
  • 766
  • 15 Mar 2024
Topic Review
Hypoxia-Related Metabolic Responses of the Fish Heart
Hypoxia imposes conflicting demands on cardio-respiratory function. Being systemically O2 supply-dependent on cardiac output (CO) and arterial O2 concentration, fish can respond to and cope with hypoxia through cardio-respiratory adjustments to preserve systemic O2 delivery, thus maintaining aerobic metabolism, or by reducing O2 demands via anaerobic metabolism or metabolic depression. In 1986, Hochachka firstly proposed metabolic arrest, i.e., a simultaneous reduction in metabolic rate and metabolic demands, as a key adaptation to O2 deprivation in organisms capable of long-term anoxic survival.
  • 761
  • 28 Jan 2023
Topic Review
Adipose-Derived Mesenchymal Stromal Cells
Being of mesodermal origin, ASCs (adipose-derived mesenchymal stromal cells) can be easily induced to differentiate into chondrocyte-like and osteocyte-like elements and used to repair damaged tissues. Moreover, they can be easily harvested and used for autologous implantation. A plethora of ASC-based strategies are being developed worldwide: they include the transplantation of freshly harvested cells, in vitro expanded cells or predifferentiated cells. Moreover, improving their positive effects, ASCs can be implanted in combination with several types of scaffolds that ensure the correct cell positioning; support cell viability, proliferation and migration; and may contribute to their osteogenic or chondrogenic differentiation. Examples of these strategies are described here, showing the enormous therapeutic potential of ASCs in this field. For safety and regulatory issues, most investigations are still at the experimental stage and carried out in vitro and in animal models. Clinical applications have, however, been reported with promising results and no serious adverse effects.
  • 760
  • 31 Jul 2023
Topic Review
Eccentric Training in Pulmonary Rehabilitation of Post-COVID-19 Patients
COVID-19, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mainly attacks cells in the respiratory system. In the acute phase of COVID-19, patients with moderate–to–severe ARDS are characterized by an elevated pro-inflammatory state secondary to a “cytokine storm” (CS). This process stimulates the generation of reactive chemical species (RS) and induces oxidative stress (OS), that has been postulated as the primary cause of tissue damage and consequent functional impairments post-COVID-19.
  • 738
  • 20 Oct 2022
Topic Review
Cells Involved in Renal Fibrosis
The kidney functions as the main site of nutrient exchange and waste removal in the body, relying heavily on its complex structure to maintain homeostasis. Three distinct compartments make up the nephron, the functional unit of the kidney. The glomerulus is involved in filtering nutrients and waste from blood, the tubulointerstitium regulates transport and nutrient exchange, and the vasculature transports blood to and from the kidney. Renal fibrosis can impact all structures of the kidney by affecting the function of specialized cells found in each compartment.
  • 738
  • 23 Dec 2022
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