Search Results (431)

Background and Objectives: Metabolic dysfunction-associated steatotic liver disease (MASLD) is a progressive liver disorder associated with metabolic risk factors such as obesity, type 2 diabetes, and cardiovascular disease. If left untreated, the accumulation of excess hepatic fat can lead to inflammation, fibrosis, cirrhosis, hepatocellular carcinoma, and ultimately liver failure. Capsaicin (CAP), the primary pungent compound in chili peppers, has previously been shown to prevent weight gain in high-fat diet (HFD)-induced obesity models. In this study, we investigated the potential of dietary CAP to prevent HFD-induced MASLD. Methods: C57BL/6 mice were fed an HFD (60% kcal from fat) with or without 0.01% CAP supplementation for 26 weeks. We evaluated CAP’s effects on hepatic fat accumulation, inflammation, and mitochondrial function to determine its role in preventing MASLD. Results: CAP acts as a potent and selective agonist of the transient receptor potential vanilloid 1 (TRPV1) channel. We confirmed TRPV1 expression in the liver and demonstrated that CAP activates hepatic TRPV1, thereby preventing steatosis, improving insulin sensitivity, reducing inflammation, and enhancing fatty acid oxidation. These beneficial effects were observed in wild-type but not in TRPV1 knockout mice. Mechanistically, CAP-induced TRPV1 activation promotes calcium influx and activates AMPK, which leads to SIRT1-dependent upregulation of PPARα and PGC-1α, enhancing mitochondrial biogenesis and lipid metabolism. Conclusions: Our findings suggest that dietary CAP prevents MASLD through TRPV1 activation. TRPV1 signaling represents a promising therapeutic target for the prevention and management of MASLD in individuals with metabolic disorders. Full article

Diabetes mellitus (DM) is one of the leading causes of death and disability worldwide and its prevalence continues to rise. Chronic hyperglycemia exposes patients to severe complications. Among these, diabetic vascular lesions are the most destructive. Their primary driver is the synergistic interaction between hyperglycemia-induced oxidative stress and chronic inflammation. This review systematically elucidates how multiple pathological pathways—namely, metabolic dysregulation, mitochondrial dysfunction, endoplasmic reticulum stress, and epigenetic reprogramming—cooperate to drive oxidative stress and inflammatory cascades. Confronting this complex pathological network, natural products, unlike conventional single-target synthetic drugs, exert multi-target synergistic effects, simultaneously modulating several key pathogenic networks. This enables the restoration of redox homeostasis and the suppression of inflammatory responses, thereby improving vascular function and delaying both microvascular and macrovascular disease progression. However, the clinical translation of natural products still faces multiple challenges and requires comprehensive mechanistic studies and rigorous validation to fully realize their therapeutic potential. Full article

In familial Alzheimer’s disease (FAD), presenilin 1 (PSEN1) E280A cholinergic-like neurons (ChLNs) induce aberrant secretion of extracellular amyloid beta (eAβ). How PSEN1 E280A ChLNs-eAβ affects microglial activity is still unknown. We obtained induced microglia-like cells (iMG) from human peripheral blood cells (hPBCs) in a 15-day differentiation process to investigate the effect of bolus addition of Aβ42, PSEN1 E280A cholinergic-like neuron (ChLN)-derived culture supernatants, and PSEN1 E280A ChLNs on wild type (WT) iMG, PSEN1 E280A iMG, and sporadic Alzheimer’s disease (SAD) iMG. We found that WT iMG cells, when challenged with non-cellular (e.g., lipopolysaccharide, LPS) or cellular (e.g., Aβ42, PSEN1 E280A ChLN-derived culture supernatants) microenvironments, closely resemble primary human microglia in terms of morphology (resembling an “amoeboid-like phenotype”), expression of surface markers (Ionized calcium-binding adapter molecule 1, IBA-1; transmembrane protein 119, TMEM119), phagocytic ability (high pHrodo™ Red E. coli BioParticles™ phagocytic activity), immune metabolism (i.e., high generation of reactive oxygen species, ROS), increase in mitochondrial membrane potential (ΔΨm), response to ATP-induced transient intracellular Ca²⁺ influx, cell polarization (cluster of differentiation 68 (CD68)/CD206 ratio: M1 phenotype), cell migration activity according to the scratch wound assay, and especially in their inflammatory response (secretion of cytokine interleukin-6, IL-6; Tumor necrosis factor alpha, TNF-α). We also found that PSEN1 E280A and SAD iMG are physiologically unresponsive to ATP-induced Ca²⁺ influx, have reduced phagocytic activity, and diminished expression of Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) protein, but when co-cultured with PSEN1 E280A ChLNs, iMG shows an increase in pro-inflammatory phenotype (M1) and secretes high levels of cytokines IL-6 and TNF-α. As a result, PSEN1 E280A and SAD iMG induce apoptosis in PSEN1 E280A ChLNs as evidenced by abnormal phosphorylation of protein TAU at residue T205 and cleaved caspase 3 (CC3). Taken together, these results suggest that PSEN1 E280A ChLNs initiate a vicious cycle between damaged neurons and M1 phenotype microglia, resulting in excessive ChLN death. Our findings provide a suitable platform for the exploration of novel therapeutic approaches for the fight against FAD. Full article

Mitochondria are critical for cellular energy, and while large deletions in their genome (mtDNA) are linked to primary mitochondrial diseases, their significance in cancer is less understood. Given cancer’s metabolic nature, investigating mtDNA deletions in tumors at various stages could provide insights into disease origins and treatment responses. In this study, we analyzed 148 bone marrow samples from 129 pediatric patients with B-cell (B-ALL) and T-cell (T-ALL) acute lymphoblastic leukemia at diagnosis, remission, and relapse using long-range PCR, next-generation sequencing, and the Splice-Break2 pipeline. Both T-ALL and B-ALL exhibited significantly more mtDNA deletions than did the controls, with T-ALL showing a ~100-fold increase and B-ALL a ~15-fold increase. The T-ALL samples also exhibited larger deletions (median size > 2000 bp) and greater heterogeneity, suggesting increased mitochondrial instability. Clustering analysis revealed distinct deletion profiles between ALL subtypes and across disease stages. Notably, large clonal deletions were detected in some B-ALL remission samples, including one affecting up to 88% of mtDNA molecules, which points toward treatment-driven selection or toxicity. A multivariate analysis confirmed that disease type, timepoint, and WHO subtype significantly influenced mtDNA deletion metrics, while age and gender did not. These findings suggest that mtDNA deletion profiling could serve as a biomarker for pediatric ALL and may indicate mitochondrial toxicity contributing to late effects in survivors. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the leading cause of chronic liver disease worldwide, affecting approximately 25–30% of the global adult population and highlighting the urgent need for effective therapeutics and prevention strategies. MASLD is characterized by excessive hepatic lipid accumulation and can progress, in a subset of patients, to metabolic dysfunction-associated steatohepatitis (MASH), a pro-inflammatory and pro-fibrotic condition associated with increased risk of liver cirrhosis and hepatocellular carcinoma. Although the molecular drivers of MASLD progression remain incompletely understood, several key metabolic pathways—such as triglyceride handling, cholesterol catabolism, bile acid metabolism, mitochondrial function, and autophagy—are consistently dysregulated in MASLD livers. This narrative review summarizes primary literature and highlights insights from recent reviews on the multifaceted role of the mRNA-binding protein Human antigen R (HuR) in the post-transcriptional regulation of critical cellular processes, including nutrient metabolism, cell survival, and stress responses. Emerging evidence underscores HuR’s essential role in maintaining liver homeostasis, particularly under metabolic stress conditions characteristic of MASLD, with hepatocyte-specific HuR depletion associated with exacerbated disease severity. Moreover, comorbid conditions such as obesity, type 2 diabetes mellitus, and cardiovascular disease not only exacerbate MASLD progression but also involve HuR dysregulation in extrahepatic tissues, further contributing to liver dysfunction. A deeper understanding of HuR-regulated post-transcriptional networks across metabolic organs may enable the development of targeted therapies aimed at halting or reversing MASLD progression. Full article

Mitochondrial dysfunction is a key driver of neurological disorders due to the brain’s high energy demands and reliance on mitochondrial homeostasis. Despite advances in genetic characterization, the heterogeneity of mitochondrial diseases complicates diagnosis and treatment. Mitochondrial dysfunction spans a broad clinical spectrum, from early-onset encephalopathies to adult neurodegeneration, with phenotypic and genetic variability necessitating integrated models of mitochondrial neuropathology. Mutations in nuclear or mitochondrial DNA disrupt energy production, induce oxidative stress, impair mitophagy and biogenesis, and lead to neuronal degeneration and apoptosis. This narrative review provides a structured synthesis of current knowledge by classifying mitochondrial-related neurological disorders according to disrupted biochemical pathways, in order to clarify links between genetic mutations, metabolic impairments, and clinical phenotypes. More specifically, a pathway-oriented framework was adopted that organizes disorders based on the primary mitochondrial processes affected: oxidative phosphorylation (OXPHOS), pyruvate metabolism, fatty acid β-oxidation, amino acid metabolism, phospholipid remodeling, multi-system interactions, and neurodegeneration with brain iron accumulation. Genetic, clinical and molecular data were analyzed to elucidate shared and distinct pathophysiological features. A comprehensive table synthesizes genetic causes, inheritance patterns, and neurological manifestations across disorders. This approach offers a conceptual framework that connects molecular findings to clinical practice, supporting more precise diagnostic strategies and the development of targeted therapies. Advances in whole-exome sequencing, pharmacogenomic profiling, mitochondrial gene editing, metabolic reprogramming, and replacement therapy—promise individualized therapeutic approaches, although hurdles including heteroplasmy, tissue specificity, and delivery challenges must be overcome. Ongoing molecular research is essential for translating these advances into improved patient care and quality of life. Full article

Postbiotics, which are non-viable microbial derivatives including short-chain fatty acids (SCFAs), microbial peptides, and cell wall components, are emerging as novel therapeutic agents for Inflammatory Bowel Disease (IBD). Unlike probiotics, postbiotics offer a safer, more stable alternative while retaining potent bioactivity. IBD, encompassing Crohn’s disease and ulcerative colitis, is characterized by chronic gastrointestinal inflammation, epithelial barrier dysfunction, and immune dysregulation. Recent evidence links mitochondrial dysfunction marked by impaired energy metabolism, oxidative stress, and apoptosis with the pathogenesis and persistence of IBD. Postbiotics have shown the ability to modulate mitochondrial health through multiple mechanisms. SCFAs such as butyrate serve as primary energy substrates for colonocytes, enhancing mitochondrial respiration and promoting biogenesis. They improve mitochondrial function and boost ATP production. Moreover, postbiotics reduce oxidative damage by regulating antioxidant defenses. These antioxidant actions limit epithelial apoptosis and preserve cellular integrity. In addition, postbiotics regulate mitophagy and help maintain mitochondrial quality and reduce inflammation. Structural components such as lipoteichoic acid and peptidoglycan have been shown to interact with mitochondrial pathways and modulate inflammatory responses. Collectively, this review explores the interplay between mitochondrial dysfunction, IBD, and preventive approach using postbiotics. Understanding the connections with postbiotics could open up new avenues for therapeutic interventions aimed at mitigating IBD severity in people with IBD. Full article

Osteoarthritis (OA) is a prevalent and debilitating joint disease in older adults with a complex etiology. We investigated the role of SUMOylation, a post-translational modification, in OA pathogenesis, focusing on the mitochondrial chaperone Prohibitin (PHB1) and the cartilage homeostasis transcription factor PITX1. We hypothesized that oxidative stress-induced SUMOylation promotes PHB1 nuclear accumulation, leading to PITX1 downregulation and contributing to OA development. Analysis of cartilage specimens from 27 OA patients and 4 healthy controls revealed an increased nuclear accumulation of PHB1 in OA chondrocytes, accompanied by elevated levels of SUMO-1 and SUMO-2/3. Mechanistically, nuclear PHB1 interacted indirectly with SUMO-1 through a SUMO-interacting motif (SIM), and the deletion of this SIM prevented PHB1 nuclear trapping in OA cells. Furthermore, the SUMO-conjugating enzyme E2 (UBC9) encoded by the UBE2I gene was upregulated in knee OA cartilage, and its overexpression in vitro enhanced PHB1 nuclear accumulation. Consistently, transgenic mice overexpressing the Ube2i gene exhibited increased UBC9 in their knee cartilage, resulting in Pitx1 downregulation and the emergence of an early OA-like phenotype in articular chondrocytes. Our findings uncover a novel role for UBC9-mediated SUMOylation in primary knee and hip OA. This pathway enhances PHB1 nuclear accumulation, contributing to PITX1 repression and subsequent OA development. These results underscore the importance of SUMOylation in OA pathogenesis and suggest potential molecular targets for early diagnosis and therapeutic intervention. Full article

Alzheimer’s disease (AD), the most common form of dementia, is a progressive neurodegenerative disorder characterized by memory loss and cognitive decline. In addition to its two major pathological hallmarks, extracellular amyloid beta (Aβ) plaques and intracellular neurofibrillary tangles (NFTs), recent evidence highlights the critical roles of mitochondrial dysfunction and neuroinflammation in disease progression. Aβ impairs mitochondrial function, which, in part, can subsequently trigger inflammatory cascades, creating a vicious cycle of neuronal damage. Estrogen receptors (ERs) are widely expressed throughout the brain, and the sex hormone 17β-estradiol (E2) exerts neuroprotection through both anti-inflammatory and mitochondrial mechanisms. While E2 exhibits neuroprotective properties, its mechanisms against Aβ toxicity remain incompletely understood. In this study, we investigated the neuroprotective effects of E2 against Aβ-induced mitochondrial dysfunction and neuroinflammation in primary cortical neurons, with a particular focus on the role of AMP-activated protein kinase (AMPK). We found that E2 treatment significantly increased phosphorylated AMPK and upregulated the expression of mitochondrial biogenesis regulator peroxisome proliferator-activated receptor gamma coactivator-1 α (PGC-1α), leading to improved mitochondrial respiration. In contrast, Aβ suppressed AMPK and PGC-1α signaling, impaired mitochondrial function, activated the pro-inflammatory nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), and reduced neuronal viability. E2 pretreatment also rescued Aβ-induced mitochondrial dysfunction, suppressed NF-κB activation, and, importantly, prevented the decline in neuronal viability. However, the pharmacological inhibition of AMPK using Compound C (CC) abolished these protective effects, resulting in mitochondrial collapse, elevated inflammation, and cell death, highlighting AMPK’s critical role in mediating E2’s actions. Interestingly, while NF-κB inhibition using BAY 11-7082 partially restored mitochondrial respiration, it failed to prevent Aβ-induced cytotoxicity, suggesting that E2’s full neuroprotective effects rely on broader AMPK-dependent mechanisms beyond NF-κB suppression alone. Together, these findings establish AMPK as a key mediator of E2’s protective effects against Aβ-driven mitochondrial dysfunction and neuroinflammation, providing new insights into estrogen-based therapeutic strategies for AD. Full article

Trypanosoma cruzi is a kinetoplastid parasite and etiological agent of Chagas disease. Given the significant morbidity and mortality rates of this parasitic disease, possible treatment alternatives need to be studied. 3-Bromopyruvate (3-BrPA) is a synthetic analog of pyruvate that was introduced in the early 21st century as an anticancer agent, affecting the proliferation and motility of certain microorganisms. Therefore, this work aims to evaluate the role of 3-BrPA in the energy metabolism, proliferation, and infectivity of T. cruzi, with a primary focus on the mitochondrial state, ATP production, and the key glycolytic pathway enzymes. It was observed that mitochondrial function in 3-BrPA cells was impaired compared to control cells. Accordingly, cells maintained in control conditions have a higher intracellular ATP content than cells maintained with 3-BrPA and higher ecto-phosphatase activity. However, the 3-BrPA reduced ecto-nuclease activity and was capable of hydrolyzing 5′-AMP, ADP, and ATP. When we evaluated two key glycolytic pathway enzymes, glucose kinase (GK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), we observed that 3-BrPA induced higher GAPDH activity but did not alter GK activity. The compensatory energy mechanisms presented in T. cruzi may influence the process of cell metabolism and, consequently, the functional infectious process, suggesting the potential use of 3-BrPA in future clinical applications for Chagas disease. Full article

The central nervous system (CNS) is highly susceptible to damage due to its limited ability to regenerate. Injuries to the CNS, whether from trauma, ischemia, or neurodegenerative diseases, disrupt both cellular and vascular structures, leading to immediate (primary) and subsequent (secondary) damage. Primary damage involves the physical disruption of cells and blood vessels, weakening the blood–brain barrier (BBB) and triggering excitotoxicity and calcium overload. Secondary damage develops over hours to days and is marked by ionic imbalance, mitochondrial dysfunction, oxidative stress, and chronic inflammation, which further aggravates tissue damage. Inflammation plays a dual role: acute inflammation helps in repair, while chronic inflammation accelerates neurodegeneration. Microglia and astrocytes play key roles in this inflammatory response, with M1-like microglia promoting pro-inflammatory responses and M2-like microglia supporting anti-inflammatory and repair processes. Neurodegenerative diseases are characterized by the accumulation of misfolded proteins such as Tau, amyloid-beta, TDP-43, and α-synuclein, which impair cellular function and lead to neuronal loss. Neurodegenerative diseases are characterized by the accumulation of misfolded proteins and influenced by genetic risk factors (e.g., APOE4, TARDBP). Despite the CNS’s limited regenerative abilities, processes like synaptogenesis, neurogenesis, axonal regeneration, and remyelination offer potential for recovery. Therapeutic approaches aim to target inflammatory pathways, enhance repair mechanisms, and develop neuroprotective treatments to counter excitotoxicity, oxidative stress, and apoptosis. Advances in stem cell therapy, gene therapy, and personalized medicine hold promise for improving outcomes. Future research should focus on combining strategies, utilizing advanced technologies, and conducting translational studies to bridge the gap between preclinical research and clinical application. By better understanding and leveraging the complex processes of CNS injury and repair, researchers hope to develop effective therapies to restore function and enhance the quality of life for individuals with CNS disorders. Full article

Background: Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterized by recurrent sinopulmonary infections due to motile cilia defects. The disease is genetically heterogeneous, with abnormalities in structural ciliary proteins. Zinc finger MYND-type containing 10 (ZMYND10) is essential for the assembly of outer dynein arms (ODA), with chaperones like Glucose-regulated protein 78 (GRP78) facilitating protein folding. This study investigates ZMYND10 and Dynein axonemal heavy chain 5 (DNAH5) mutations in individuals with PCD. Methods: Eight individuals aged 14–22 with clinical PCD symptoms and confirmed DNAH5 mutations were included. We analyzed the correlation between DNAH5 abnormalities and preassembly/chaperone proteins using immunofluorescence labeling. Nasal swabs were double-labeled (DNAH5–β-tubulin, β-tubulin–ZMYND10, β-tubulin–GRP78) and examined via fluorescence microscopy. Serum metabolomics and proteomics were also assessed. Results: The corrected total cell fluorescence (CTCF) levels of DNAH5, ZMYND10, and GRP78 were significantly different between PCD individuals and controls. Metabolomic analysis showed reduced valine, leucine, and isoleucine biosynthesis, with increased malate and triacylglycerol biosynthesis, malate-aspartate and glycerol phosphate shuttles, and arginine/proline metabolism, suggesting mitochondrial and ER stress. Conclusions: The altered expression of DNAH5, ZMYND10, and GRP78, along with metabolic shifts, points to a complex link between ciliary dysfunction and cellular stress in PCD. Further studies are needed to clarify the underlying mechanisms. Full article

AarF domain-containing kinases (ADCKs) are a family of putative mitochondrial proteins that have been implicated in various aspects of mitochondrial function and cellular metabolism. Mitochondria play a crucial role in cellular bioenergetics, primarily in adenosine triphosphate (ATP) production, while also regulating metabolism, thermogenesis, apoptosis, and reactive oxygen species (ROS) generation. Evidence suggests that the ADCK family of proteins is involved in maintaining mitochondrial architecture and homeostasis. In detail, these proteins are believed to play a role in processes such as coenzyme Q biosynthesis, energy production, and cellular metabolism. There are five known isoforms of ADCK (ADCK1–ADCK5), some of which have similar activities, and each also has its own unique biological functions. Dysregulation or mutations in specific ADCK isoforms have been linked to several pathological conditions, including multiple human cancers, primary coenzyme Q10 (CoQ10) deficiency, and metabolic disorders. This review surveys the current body of peer-reviewed research on the ADCK protein family, incorporating data from the primary literature, case studies, and experimental studies conducted in both in vitro and in vivo systems. It also draws on existing review articles and known published findings to provide a comprehensive overview of the functional roles, disease associations, and molecular mechanisms of ADCK proteins. Further in-depth research on ADCK proteins has the potential to unlock critical insights into their precise mechanisms. This could pave the way for identifying new therapeutic targets for mitochondrial and metabolic-related diseases, as well as for advancing cancer treatment strategies. Full article

Pediatric hypertension is increasingly recognized as a complex condition shaped by both systemic and cellular factors, with oxidative stress emerging as a key driver of vascular dysfunction. In both their primary and secondary forms, reactive oxygen species (ROS) disrupt redox homeostasis, impair endothelial signaling, and promote inflammation and tissue remodeling. Metabolic dysregulation, renal pathology, and early-life stressors contribute to the accumulation of ROS through pathways involving NADPH oxidases, mitochondrial dysfunction, xanthine oxidase activity, and altered arginine metabolism. These mechanisms converge on the vasculature, diminishing nitric oxide bioavailability and promoting hypertensive phenotypes. Beyond disease initiation, redox imbalance influences the response to treatment, surgical outcomes, and long-term cardiovascular risk. By further elucidating these mechanisms, the complex relationship between oxidative stress, vascular biology, and blood pressure regulation in children may be more clearly defined and more effectively targeted in clinical management. Full article

The protein associated with the silencing information regulator 2-associated enzyme1 (SIRT1) is a highly conserved nicotinamide adenine dinucleotide (NAD⁺)-dependent deacetylase and a key member of the sirtuin family. SIRT1 plays an essential role in various cellular physiological processes, primarily localized in the nucleus but also active in the cytoplasm and mitochondria. Recent studies have demonstrated its capacity to delay aging in multiple organs and tissues, although its underlying mechanisms remain incompletely understood. Additionally, SIRT1 exerts a significant influence on metabolic regulation and genetic processes. As the primary source of cellular energy, mitochondria are central to numerous biological functions. Mitochondrial dysfunction has been implicated in the onset and progression of various diseases and is increasingly recognized for its role in aging-related processes. This article investigates the interaction between SIRT1 and mitochondria in regulating reproductive system aging and elucidates their potential mechanisms of action, providing insights for clinical research into reproductive system aging. Full article