Search Results (2,400)

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder primarily characterized by memory loss and cognitive decline, which significantly impacts patients’ quality of life and imposes substantial emotional, practical, and economic burdens on their families. As the most common cause of senile dementia, AD currently affects approximately 50 million people worldwide, with projections indicating a threefold increase by 2050 due to rising life expectancy and an aging global population. Diagnosis of AD remains challenging. Neuroimaging techniques reveal atrophy in critical brain regions, particularly in the cortex, hippocampus, and limbic system, which are essential substrates for memory, personality changes, and other cognitive functions. The hallmark molecular changes associated with AD include the accumulation of β-amyloid plaques and the formation of tau protein tangles. Several underlying mechanisms contribute to neuron loss, such as oxidative stress, neuroinflammation, microbial dysbiosis, and insulin resistance. In this context, exosomes—small extracellular vesicles that facilitate cell communication—transport proteins, DNA, mRNA, and non-coding RNA (ncRNA), all of which play a significant role in the neurobiology of AD. Furthermore, emerging research indicates that exosomal ncRNAs may serve as promising biomarkers for AD, offering the possibility of improved diagnostic precision. This review explores the potential of exosomal ncRNAs—specifically circular RNAs and microRNAS—as non-invasive biomarkers for AD, highlighting recent advances and future directions in translational studies. Full article

Cirrhotic cardiomyopathy (CCM) is a cardiac dysfunction in patients with cirrhosis, occurring in the absence of structural heart disease. It increases perioperative risk, especially in liver transplantation, and may contribute to hepatorenal syndrome. Despite its clinical significance, CCM remains poorly understood and lacks effective treatments. This review aims to summarize recent findings on the pathogenesis of CCM and highlight potential therapeutic targets. A focused literature review was conducted using PubMed, Scopus, and Clarivate databases, selecting studies from the last five years. Included studies investigated molecular, cellular, and receptor-mediated mechanisms involved in CCM. Results: CCM results from neurohumoral, inflammatory, and electrophysiological disturbances. Key mechanisms involve dysfunction of β-adrenergic and muscarinic receptors, altered ion channels (potassium, L-type calcium), impaired sodium–calcium exchange, and suppression of the P2X7 receptor (P2X7R). Dysregulation of the CD73 (5’-nucleotidase, ecto-5’-nucleotidase)–A2 adenosine axis, along with effects from endocannabinoids, nitric oxide (NO) inhibition by tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6), carbon monoxide (CO), and elevated galectin-3 (Gal-3), further contribute to myocardial dysfunction. Conclusions: CCM is a multifactorial condition linked to systemic and myocardial effects of cirrhosis. A deeper understanding of its mechanisms is essential for developing targeted therapies. Further research is needed to improve patient outcomes. Full article

Chronic inflammation underpins the pathogenesis of both rheumatoid arthritis (RA) and neurodegenerative conditions such as Alzheimer’s disease (AD). This narrative review explores the role of C-reactive protein (CRP), particularly its monomeric form (mCRP), as a central molecular link connecting systemic autoimmune inflammation with neuroinflammatory and vascular pathology. In RA, fibroblast-like synoviocytes (FLSs) are activated by CRP through CD32/CD64-mediated signaling, triggering proinflammatory cascades involving NF-κB and p38 MAPK. Recent studies have highlighted that locally synthesized CRP within the synovium may convert to mCRP, amplifying inflammation and tissue damage. Beyond RA, mCRP has been identified within amyloid-beta (Aβ) plaques in AD brains, suggesting a direct role in neurodegenerative pathology. Experimental models also demonstrate that mCRP is upregulated in stroke-affected brain regions and associated with complement activation and blood–brain barrier (BBB) disruption, which is central to AD progression. The convergence of pathways involving IL-6, RAGE (receptor for advanced glycation end-products), and mCRP-mediated complement activation reveals a shared axis of inflammation between RA and AD. This highlights the potential of mCRP not only as a biomarker of chronic inflammation but also as a therapeutic target. Furthermore, evidence from periodontal disease and cardiovascular comorbidities highlights the systemic nature of mCRP-driven inflammation, offering insights into the mechanisms of disease overlap. This review advocates for further mechanistic studies into mCRP signaling, particularly its role at the interface of systemic and neuroinflammation, with the goal of identifying new interventional strategies for patients with RA at elevated risk of neurodegenerative and vascular complications. Full article

Alzheimer’s disease (AD) and major depressive disorder (MDD) are prevalent central nervous system (CNS) disorders that share overlapping symptoms but differ in underlying molecular mechanisms. Distinguishing these mechanisms is essential for developing targeted diagnostic and therapeutic strategies. In this study, we integrated multi-tissue transcriptomic datasets from brain and peripheral samples to identify differentially expressed microRNAs (miRNAs) in AD and MDD. Functional enrichment analyses (KEGG, GO) revealed that dysregulated miRNAs in AD were associated with MAPK, PI3K–Akt, Ras, and PD-1/PD-L1 signaling, pathways linked to synaptic plasticity, neuroinflammation, and immune regulation. In contrast, MDD-associated miRNAs showed enrichment in Hippo signaling and ubiquitin-mediated proteolysis, implicating altered neurogenesis and protein homeostasis. Network analysis highlighted key disease- and tissue-specific miRNAs, notably hsa-miR-1202 and hsa-miR-24-3p, with potential roles in neuronal survival and molecular network regulation. These findings suggest that miRNAs may serve as non-invasive biomarkers for diagnosis, prognosis, and treatment monitoring in both disorders. While therapeutic targeting of miRNAs offers promise, challenges such as blood–brain barrier penetration and tissue-specific delivery remain. This integrative approach provides a translational framework for advancing miRNA-based strategies in CNS disease research. Full article

Cellular senescence is a fundamental hallmark of aging, contributing to tissue dysfunction and chronic disease through the senescence-associated secretory phenotype (SASP). The SASP encompasses a diverse and dynamic collection of secreted cytokines, chemokines, growth factors, and proteases that vary depending on cell type, senescence trigger, and microenvironmental context. Accurate quantification of SASP components is critical to understanding the mechanisms linking senescence to pathology and for advancing senotherapeutic strategies. However, measuring the SASP presents significant technical and biological challenges due to its complexity, heterogeneity, and context dependence. This review provides a comprehensive overview of the principal methodologies used to measure SASP components across different biological levels—transcriptional, translational, and functional—and sample types, including cell cultures, tissues, and systemic fluids. We discuss the advantages and limitations of widely used RNA-level techniques (e.g., qRT-PCR, RNA sequencing, in situ hybridization), protein-level assays (e.g., ELISA, Western blotting, mass spectrometry, Luminex, MSD), and spatial detection methods (e.g., immunohistochemistry, immunofluorescence). By organizing current SASP detection strategies by molecular level and sample source, this review highlights the importance of multiparametric approaches to capture the full spectrum of senescent cell activity. We also identify key methodological gaps and propose directions for refining SASP biomarker discovery in aging and disease research. Full article

Heart failure (HF) remains a major global health challenge defined by the inability of the heart to adequately meet systemic metabolic requirements. While ventricular dysfunction has traditionally been the primary focus in both conceptual and clinical frameworks of HF, emerging evidence highlights atrial myopathy—covering structural, functional, electrical, metabolic, and neurohormonal remodeling—as a central yet often overlooked contributor to disease progression across the HF spectrum. This review offers a comprehensive overview of the molecular and cellular mechanisms underlying atrial remodeling, with a focus on inflammation and innate immune activation as key pathogenic mediators. Among pattern recognition receptors, Toll-like receptors (TLRs) and NOD-like receptors (NLRs) play crucial roles in translating myocardial stress into pro-inflammatory, profibrotic, and pro-arrhythmic signals that exacerbate HF. By combining experimental and clinical evidence, we emphasize atrial myopathy as both a biomarker and an active driver of HF deterioration, advocating for the inclusion of atrial-targeted diagnostics and immunomodulatory therapies in future HF treatment approaches. Such a paradigm shift holds significant potential for improved risk stratification, arrhythmia prevention, attenuation of structural remodeling, and ultimately, better prognosis and clinical outcomes in this increasingly common syndrome. Full article

Obesity represents a significant global public health challenge, which not only elevates the risk of mortality but also increases the likelihood of chronic diseases. The ongoing obesity epidemic has led to a growing recognition of the detrimental effects of excessive adipose tissue accumulation on male reproductive health. Substantial evidence indicates that obesity adversely affects sperm quality, thereby impairing male fertility. Specifically, obesity is associated with compromised spermatogenesis, erectile dysfunction, and detrimental effects on offspring fertility parameters. These effects are mediated through various mechanisms, including alterations in the hypothalamic–pituitary–gonadal axis, inflammation within the reproductive system, localized caloric excess in reproductive tissues, epigenetic modifications, disruptions in gut microbiota, and heightened oxidative stress levels. While the molecular alterations associated with obesity have been extensively documented, the precise mechanisms by which obesity influences male reproductive function remain inadequately understood. This article aimed to review the classification and distribution of adipose tissue in obesity, the impact of obesity on male fertility, and the potential mechanisms through which obesity affects male reproductive health, thereby offering insights into the prevention and treatment of obesity-related male fertility issues. Full article

Microglia and macrophages are critical immune cells within the central nervous system (CNS), with distinct roles in development, homeostasis, and disease. Once viewed as passive bystanders, these cells are now recognized for their dynamic phenotypic plasticity, which enables them to respond to a wide range of physiological and pathological stimuli. During homeostasis, microglia and CNS-resident macrophages actively participate in synaptic pruning, neuronal support, myelin regulation, and immune surveillance, contributing to CNS integrity. However, under pathological conditions, these cells can adopt neurotoxic phenotypes, exacerbating neuroinflammation, oxidative stress, and neuronal damage in diseases such as Alzheimer’s, Parkinson’s, multiple sclerosis, and glioblastoma. This review synthesizes emerging insights into the molecular, epigenetic, and metabolic mechanisms that govern the behavior of microglia and macrophages, highlighting their developmental origins, niche-specific programming, and interactions with other CNS cells. We also explore novel therapeutic strategies aimed at modulating these immune cells to restore CNS homeostasis, including nanotechnology-based approaches for selective targeting, reprogramming, and imaging. Understanding the complex roles of microglia and macrophages in both health and disease is crucial for the development of precise therapies targeting neuroimmune interfaces. Continued advances in single-cell technologies and nanomedicine are paving the way for future therapeutic interventions in neurological disorders. Full article

Aortic stenosis (AS) and atherosclerosis are progressive cardiovascular conditions that frequently coexist and share multiple clinical and molecular features. Medical therapies have shown effectiveness in preventing and treating atherosclerosis and its consequences. For AS, effective pharmacological therapies remain limited. Understanding the shared risk factors and mechanisms between the two conditions may provide opportunities for therapeutic repositioning in AS. We performed a narrative review focusing on studies published from 2005 to 2025. Inclusion criteria encompassed clinical trials, experimental models, and molecular studies addressing overlapping risk factors, pathological pathways, and treatment approaches for AS and atherosclerosis. AS and atherosclerosis share key risk factors, including age, hypertension, hyperlipidemia, and diabetes. Molecular mechanisms, such as chronic inflammation, endothelial dysfunction, oxidative stress, lipid accumulation, and calcific remodeling, are common to both. Pathways involving the renin-angiotensin system, Notch signaling, and osteogenic mediators contribute to disease progression. Several drug classes, notably proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, lipoprotein(a) (Lp(a)) lowering therapies, anti-inflammatory agents, and immunomodulators, show potential for repositioning in AS management. The substantial overlap in risk factors and molecular mechanisms between AS and atherosclerosis supports a rationale for therapeutic repositioning. Targeting shared pathways could lead to innovative strategies for slowing AS progression and improving patient outcomes. Full article

Intercellular communication in the central nervous system (CNS) is essential for maintaining neural function and coordinating responses to injury or disease. With recent advances in single-cell and spatial transcriptomics, a growing body of research has revealed that this communication is highly dynamic, shifting across states of health, aging, demyelination, and neurodegeneration. In this review, we synthesize the current findings on intercellular communication networks involving neurons, astrocytes, microglia, oligodendrocytes, and other glial populations in the CNS across four major states: healthy homeostasis, aging, demyelinating diseases, and Alzheimer’s disease (AD). We focus on how changes in intercellular communication contribute to the maintenance or disruption of CNS integrity and function. Mechanistic insights into these signaling networks have revealed new molecular targets and pathways that may be exploited for therapeutic intervention. By comparing the intercellular signaling mechanisms across different disease contexts, we underscore the importance of CNS crosstalk not only as a hallmark of disease progression, but also as a potential gateway for precision therapy. Full article

The renin-angiotensin system (RAS) has evolved from being considered solely a peripheral endocrine system for cardiovascular control to being recognized as a complex molecular network with important functions in the central nervous system (CNS) and peripheral nervous system (PNS). Here we examine the organization, mechanisms of action, and clinical implications of cerebral RAS in physiological conditions and in various neurological pathologies. The cerebral RAS operates autonomously, synthesizing its main components locally due to restrictions imposed by the blood–brain barrier. The key elements of the system are (pro)renin; (pro)renin receptor (PRR); angiotensinogen; angiotensin-converting enzyme types 1 and 2 (ACE1 and ACE2); angiotensin I (AngI), angiotensin II (AngII), angiotensin III (AngIII), angiotensin IV (AngIV), angiotensin A (AngA), and angiotensin 1-7 (Ang(1-7)) peptides; RAS-regulating aminopeptidases; and AT1 (AT1R), AT2 (AT2R), AT4 (AT4R/IRAP), and Mas (MasR) receptors. More recently, alamandine and its MrgD receptor have been included. They are distributed in specific brain regions such as the hypothalamus, hippocampus, cerebral cortex, and brainstem. The system is organized into two opposing axes: the classical axis (renin/ACE1/AngII/AT1R) with vasoconstrictive, proinflammatory, and prooxidative effects, and the alternative axes AngII/AT2R, AngIV/AT4R/IRAP, ACE2/Ang(1-7)/MasR and alamandine/MrgD receptor, with vasodilatory, anti-inflammatory, and neuroprotective properties. This functional duality allows us to understand its role in neurological physiopathology. RAS dysregulation is implicated in multiple neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and neuropsychiatric disorders such as depression and anxiety. In brain aging, an imbalance toward hyperactivation of the renin/ACE1/AngII/AT1R axis is observed, contributing to cognitive impairment and neuroinflammation. Epidemiological studies and clinical trials have shown that pharmacological modulation of the RAS using ACE inhibitors (ACEIs) and AT1R antagonists (ARA-II) not only controls blood pressure but also offers neuroprotective benefits, reducing the incidence of cognitive decline and dementia. These effects are attributed to direct mechanisms on the CNS, including reduction of oxidative stress, decreased neuroinflammation, and improved cerebral blood flow. Full article

Type 2 diabetes (T2D) is a complex metabolic disease characterized by chronic hyperglycemia due to insulin resistance and inadequate insulin secretion. Beyond the classically implicated organs, emerging evidence highlights the gut as a central player in T2D pathophysiology through its interactions with metabolic organs. The gut hosts trillions of microbes and enteroendocrine cells that influence inflammation, energy homeostasis, and hormone regulation. Disruptions in gut homeostasis (dysbiosis and increased permeability) have been linked to obesity, insulin resistance, and β-cell dysfunction, suggesting multifaceted “Gut-X axes” contribute to T2D development. We aimed to comprehensively review the evidence for gut-mediated crosstalk with the pancreas, endocrine system, liver, and kidneys in T2D. Key molecular mechanisms (incretins, bile acids, short-chain fatty acids, endotoxins, etc.) were examined to construct an integrated model of how gut-derived signals modulate metabolic and inflammatory pathways across organs. We also discuss clinical implications of targeting Gut-X axes and identify knowledge gaps and future research directions. A literature search (2015–2025) was conducted in PubMed, Scopus, and Web of Science, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews). Over 150 high-impact publications (original research and review articles from Nature, Cell, Gut, Diabetologia, Lancet Diabetes & Endocrinology, etc.) were screened. Data on gut microbiota, enteroendocrine hormones, inflammatory mediators, and organ-specific outcomes in T2D were extracted. The GRADE framework was used informally to prioritize high-quality evidence (e.g., human trials and meta-analyses) in formulating conclusions. T2D involves perturbations in multiple Gut-X axes. This review first outlines gut homeostasis and T2D pathogenesis, then dissects each axis: (1) Gut–Pancreas Axis: how incretin hormones (GLP-1 and GIP) and microbial metabolites affect insulin/glucagon secretion and β-cell health; (2) Gut–Endocrine Axis: enteroendocrine signals (e.g., PYY and ghrelin) and neural pathways that link the gut with appetite regulation, adipose tissue, and systemic metabolism; (3) Gut–Liver Axis: the role of microbiota-modified bile acids (FXR/TGR5 pathways) and bacterial endotoxins in non-alcoholic fatty liver disease (NAFLD) and hepatic insulin resistance; (4) Gut–Kidney Axis: how gut-derived toxins and nutrient handling intersect with diabetic kidney disease and how incretin-based and SGLT2 inhibitor therapies leverage gut–kidney communication. Shared mechanisms (microbial SCFAs improving insulin sensitivity, LPS driving inflammation via TLR4, and aryl hydrocarbon receptor ligands modulating immunity) are synthesized into a unified model. An integrated understanding of Gut-X axes reveals new opportunities for treating and preventing T2D. Modulating the gut microbiome and its metabolites (through diet, pharmaceuticals, or microbiota therapies) can improve glycemic control and ameliorate complications by simultaneously influencing pancreatic islet function, hepatic metabolism, and systemic inflammation. However, translating these insights into clinical practice requires addressing gaps with robust human studies. This review provides a state-of-the-art synthesis for researchers and clinicians, underlining the gut as a nexus for multi-organ metabolic regulation in T2D and a fertile target for next-generation therapies. Full article

Amyotrophic lateral sclerosis (ALS) is still a heterogeneous neurodegenerative disorder that can be identified clinically and biologically, without a strong set of biomarkers that can adequately measure its fast rate of progression and molecular heterogeneity. In this review, we intend to consolidate the most relevant and timely advances in ALS biomarker discovery, in order to begin to bring molecular, imaging, genetic, and digital areas together for potential integration into a precision medicine approach to ALS. Our goal is to begin to display how several biomarkers in development (e.g., neurofilament light chain (NfL), phosphorylated neurofilament heavy chain (pNfH), TDP-43 aggregates, mitochondrial stress markers, inflammatory markers, etc.) are changing our understanding of ALS and ALS dynamics. We will attempt to provide a framework for thinking about biomarkers in a systematic way where our candidates are not signals alone but part of a tethered pathophysiological cascade. We are particularly interested in the fast progressor phenotype, a devastating and under-characterized subset of ALS due to a rapid axonal degeneration, early respiratory failure, and very short life span. We will try to highlight the salient molecular features of this ALS subtype, including SOD1 A5V toxicity, C9orf72 repeats, FUS variants, mitochondrial collapse, and impaired autophagy mechanisms, and relate these features to measurable blood and CSF (biomarkers) and imaging platforms. We will elaborate on several interesting tools, for example, single-cell transcriptomics, CSF exosomal cargo analysis, MRI techniques, and wearable sensor outputs that are developing into high-resolution windows of disease progression and onset. Instead of providing a static catalog, we plan on providing a conceptual roadmap to integrate biomarker panels that will allow for earlier diagnosis, real-time disease monitoring, and adaptive therapeutic trial design. We hope this synthesis will make a meaningful contribution to the shift from observational neurology to proactive biologically informed clinical care in ALS. Although there are still considerable obstacles to overcome, the intersection of a precise molecular or genetic association approach, digital phenotyping, and systems-level understandings may ultimately redefine how we monitor, care for, and treat this challenging neurodegenerative disease. Full article

Diabetes is increasingly recognized as a chronic inflammatory disease marked by systemic metabolic disturbances, with endothelial dysfunction playing a central role in its complications. Hyperglycemia, a hallmark of diabetes, drives endothelial damage by inducing excessive reactive oxygen species (ROS) production, particularly hydrogen peroxide (H₂O₂). This oxidative stress impairs endothelial cells, which are vital for vascular health, leading to severe complications such as diabetic nephropathy, retinopathy, and coronary artery disease—major causes of morbidity and mortality in diabetic patients. Recent studies have highlighted the therapeutic potential of placenta-derived mesenchymal stem cells (pMSCs), in mitigating these complications. pMSCs exhibit anti-inflammatory, antioxidant, and tissue-repair properties, showing promise in reversing endothelial damage in laboratory settings. To explore their efficacy in a more physiologically relevant context, we used a streptozotocin (STZ)-induced diabetic mouse model, which mimics type 1 diabetes by destroying pancreatic beta cells and causing hyperglycemia. pMSCs were administered via intra-peritoneal injections, and their effects on endothelial injury and tissue damage were assessed. Metabolic tests, including glucose tolerance tests (GTTs) and insulin tolerance tests (ITTs) revealed that pMSCs did not restore metabolic homeostasis or improve glucose regulation. However, histopathological kidney, heart, and eye tissue analyses demonstrated significant protective effects. pMSCs preserved glomerular structure in the kidneys, protected cardiac blood vessels, and maintained retinal integrity, suggesting their potential to address diabetes-related tissue injuries. Although these findings underscore the therapeutic potential of pMSCs for diabetic complications, further research is needed to optimize dosing, elucidate molecular mechanisms, and evaluate long-term safety and efficacy. Combining pMSCs with other therapies may enhance their benefits, paving the way for future clinical applications. Full article

Phytophthora blight, caused by Phytophthora capsici, is a destructive disease that significantly constrains the production of chayote (Sechium edule) in Mexico, leading to substantial yield and economic losses. The increasing ineffectiveness of synthetic fungicides and associated environmental concerns underscore the need for sustainable control alternatives. This study evaluated the antifungal efficacy of low molecular weight chitosan (75–85% deacetylation; Sigma-Aldrich) against P. capsici under in vitro and in vivo conditions. Chitosan solutions (0.1–3.0 g L⁻¹) were tested for their ability to inhibit pathogen growth and suppress disease symptoms. In vitro assays demonstrated a concentration-dependent inhibition of mycelial growth, with the highest dose (3.0 g L⁻¹) reducing radial expansion by 32.6%. In fruit inoculation experiments, treatment with 1.0 g L⁻¹ chitosan decreased lesion size by 50.9%, while the same concentration reduced disease severity index (DSI) by 50% in whole plants. Notably, symptom suppression was observed in tissues not directly exposed to chitosan, suggesting the activation of systemic resistance. Although the underlying molecular mechanisms were not directly assessed, the results support the dual role of chitosan as a direct antifungal agent and a potential inducer of host defense responses. These findings highlight the potential of chitosan as a biodegradable, low-toxicity alternative to synthetic fungicides and support its integration into sustainable management strategies for Phytophthora blight in chayote production systems. Full article