Search Results (1,075)

Ceramide kinase (CerK) catalyzes the phosphorylation of ceramide to ceramide-1-phosphate (C1P), a bioactive sphingolipid with diverse signaling roles. While CerK has been identified in several cellular compartments, its presence and functional significance in kidney proximal tubules remain unexplored. Herein, we report the first characterization of CerK activity in basolateral membranes (BLMs) from porcine proximal tubule cells. We demonstrate that BLM fractions contain neutral and acidic sphingomyelinases, providing local substrate for CerK, which efficiently generates C1P under physiological pH (6.5–7.2) and temperature (30–37 °C) conditions. Enzyme activity was stimulated by cAMP in a protein kinase A-dependent manner but was not affected by angiotensin II. Lipidomic analysis confirmed the presence of C1P in human proximal tubule (HK-2) cells under basal conditions and revealed changes during ischemic stress. Transcriptomic analysis of kidney biopsies from patients with chronic kidney disease (CKD) further uncovered coordinated remodeling of sphingolipid metabolism genes, with increased expression of ceramidases (ASAH1 and NAAA) and downregulation of ceramide synthases (CERS4, CERS5), consistent with adaptive regulation of the Cer/CerK/C1P axis. Together, these findings identify for the very first time CerK activity in renal BLM, establish its biochemical requirements, and highlight its potential role in modulating transporter function and sphingolipid signaling in physiology and kidney disease. Full article

Diabetic nephropathy (DN) remains the leading cause of end-stage renal disease worldwide, with proximal tubular epithelial cells (PTECs) playing a central role in its pathogenesis. Under hyperglycemic conditions, PTECs drive a pathological triad of inflammation, apoptosis, and fibrosis. Recent advances reveal that these processes interact synergistically to form a self-perpetuating vicious cycle, rather than operating in isolation. This review systematically elucidates the molecular mechanisms underlying this crosstalk in PTECs. Hyperglycemia induces reactive oxygen species (ROS) overproduction, advanced glycation end products (AGEs) accumulation, and endoplasmic reticulum stress (ERS), which collectively activate key inflammatory pathways (NF-κB, NLRP3, cGAS-STING). The resulting inflammatory milieu triggers apoptosis via death receptor and mitochondrial pathways, while apoptotic cells release damage-associated molecular patterns (DAMPs) that further amplify inflammation. Concurrently, fibrogenic signaling (TGF-β1/Smad, Hippo-YAP/TAZ) promotes epithelial–mesenchymal transition (EMT) and extracellular matrix (ECM) deposition. Crucially, the resulting fibrotic microenvironment reciprocally exacerbates inflammation and apoptosis through mechanical stress and hypoxia. Quantitative data from preclinical and clinical studies are integrated to underscore the magnitude of these effects. Current therapeutic strategies are evolving toward multi-target interventions against this pathological network. We contrast the paradigm of monotargeted agents (e.g., Finerenone, SGLT2 inhibitors), which offer high specificity, with that of multi-targeted natural product-based formulations (e.g., Huangkui capsule, Astragaloside IV), which provide synergistic multi-pathway modulation. Emerging approaches (metabolic reprogramming, epigenetic regulation, mechanobiological signaling) hold promise for reversing fibrosis. Future directions include leveraging single-cell technologies to decipher PTEC heterogeneity and developing kidney-targeted drug delivery systems. We conclude that disrupting the inflammation–apoptosis–fibrosis vicious cycle in PTECs is central to developing next-generation therapies for DN. Full article

In the last twenty years, an increasing volume of research has characterized lipids as dynamic signaling molecules that play essential roles in various physiological and pathological processes, especially concerning chronic diseases such as cardiovascular disorders, diabetes, liver disease, neurodegeneration, cancer, obesity, diabetic and chronic kidney diseases and atherosclerosis. Dysregulation of lipid synthesis and storage, lipolysis, fatty acid oxidation, lipid signaling pathways, and organelle-specific lipid modifications, including mitochondrial phospholipid remodeling and endoplasmic reticulum stress induced by saturated fatty acids, are recognized as contributors to the initiation and progression of this pathogenesis. Concurrently with the increasing comprehension of lipid metabolism, the last decade has seen progress in the understanding of genome control, especially with non-coding RNAs (ncRNAs). MicroRNAs, long non-coding RNAs, and circular RNAs, as ncRNAs, are essential modulators of gene expression at the epigenetic, transcriptional, and post-transcriptional levels that affect a number of lipid metabolism-related processes, such as fatty acid synthesis and oxidation, cholesterol homeostasis, and lipid droplet dynamics. Therapeutically, ncRNAs hold considerable promise owing to their tissue specificity and modularity, with antisense oligonucleotides and CRISPR-based editing currently under preclinical evaluation. In this context, we review recent studies exploring the interplay between ncRNAs and the regulatory networks governing lipid metabolism, and how disruptions in these networks contribute to chronic disease. This emerging paradigm underscores the role of ncRNA–lipid metabolism interactions as central nodes in metabolic and inflammatory pathways, highlighting the need for a holistic approach to therapeutic targeting. Full article

Pandemics place extraordinary pressure on healthcare systems, particularly in identifying and prioritizing high-risk groups such as the elderly, pregnant women, and individuals with chronic diseases. Existing Artificial Intelligence models often fall short, focusing on single diseases, lacking interpretability, and overlooking patient-specific vulnerabilities. To address these gaps, we propose an Explainable Deep Learning approach for identifying at-risk patients during pandemics (AI-RiskX). AI-RiskX performs risk classification of patients diagnosed with COVID-19 or related infections to support timely intervention and resource allocation. Unlike previous models, AI-RiskX integrates five public datasets (asthma, diabetes, heart, kidney, and thyroid), employs the Synthetic Minority Over-sampling Technique (SMOTE) for class balancing, and uses a hybrid convolutional neural network–long short-term memory model (CNN–LSTM) for robust disease classification. SHAP (SHapley Additive exPlanations) enables both individual and population-level interpretability, while a post-prediction rule-based module stratifies patients by age and pregnancy status. Achieving 98.78% accuracy, AI-RiskX offers a scalable, interpretable solution for equitable classification and decision support in public health emergencies. Full article

Vascular calcification is a complex, regulated process characterized by the pathological deposition of calcium phosphate minerals in the vascular wall, contributing to cardiovascular morbidity and mortality, particularly in patients with chronic kidney disease (CKD), diabetes, and aging. Once thought to be a passive degenerative process, it is now recognized as an active, cell-mediated phenomenon that shares molecular features with bone formation. Beyond traditional risk factors such as hyperphosphatemia and inflammation, disturbances in iron metabolism have recently emerged as modulators of vascular calcification. Iron, a vital trace element involved in numerous cellular functions, exhibits a dual role as both a potential driver and inhibitor of calcification, depending on its dose, distribution, and cellular context. In this review, we summarize in vitro and in vivo studies investigating the impact of iron on the osteochondrogenic differentiation and calcification of vascular smooth muscle cells and valve interstitial cells. We further highlight mechanistic insights that may explain the divergent findings reported in the literature. Finally, we compile clinical evidence linking disturbances in iron metabolism with coronary artery calcification and cardiovascular mortality in CKD patients. Full article

Sodium-glucose cotransporter-2 (SGLT2) inhibitors, also known as gliflozins, are a class of antidiabetic agents that act independently of insulin by promoting renal glucose excretion. They modulate glucose reabsorption in proximal renal tubules. Initially, they were used for the treatment of type 2 diabetes mellitus (T2DM); however, numerous pleiotropic benefits beyond glycemic control were observed. Large clinical trials confirmed their efficacy in reducing cardiovascular mortality, heart failure hospitalizations, and progression of chronic kidney disease. SGLT2 inhibitors reduce oxidative stress and inflammation and induce favorable metabolic adaptations, including lowering ketosis and upregulation of erythropoiesis. They also exert protective effects on hepatic and cognitive function. Additionally, SGLT2 inhibitors lower serum uric acid and reduce adipose tissue mass, which usually results in weight loss. Although generally well-tolerated, they are associated with increased risk of urogenital infections, euglycemic ketoacidosis, and a potentially enlarged amputation risk. Current guidelines worldwide recommend their use not only for T2DM but also for heart failure and chronic kidney disease, marking a paradigm shift toward organ-protective therapies. This review provides a comprehensive synthesis of current evidence on the mechanisms, clinical benefits, and safety profile of SGLT2 inhibitors, highlighting their expanding role in cardiometabolic and multisystem disease management. Full article

Aeromonas veronii is a major pathogen threatening freshwater aquaculture, yet the molecular mechanisms of Pelteobagrus vachellii’s immune response to this infection remain unclear. This study integrated histopathology, mRNA-seq and small RNA-seq to investigate P. vachellii’s response to A. veronii at 48 h post-challenge. Histopathologically, infection induced gill epithelial detachment, hepatocyte swelling with cytoplasmic vacuolation, and melanomacrophage centers (MMCs) in the mid-kidney (histological assessment of the head kidney was not feasible due to sampling limitations associated with its small size). Transcriptomic analysis identified 1210 differentially expressed genes (DEGs) in the head kidney (819 downregulated, 391 upregulated), significantly enriched in 11 immune pathways (e.g., NF-κB, Th17 cell differentiation, Complement and coagulation cascades), with key immune genes (e.g., IL-1β, TCRα, CCL4) upregulated. Gene Set Enrichment Analysis (GSEA) revealed activation of the proteasome, ribosome and oxidative phosphorylation pathways, and suppression of the autophagy-animal, FoxO and AMPK pathways. Small RNA-seq identified 544 known and 958 novel miRNAs in the head kidney, with 42 downregulated and 36 upregulated differentially expressed miRNAs (DE miRNAs). The miRNA-mRNA network showed that DE miRNAs (e.g., miR-101-y/z, miR-132-z, miR-3167-y) negatively regulated immune-related target genes (IL-1R1, IRF4, IκBα) in core immune pathways. Collectively, this study clarifies the pathological and miRNA-mRNA regulatory modules of P. vachellii head kidney against A. veronii infection, providing valuable information that enables the further analyses of the defense mechanisms of P. vachellii against A. veronii infection. Full article

Copper is an essential trace element that supports numerous physiological functions; however, excessive copper accumulation can disrupt cellular and biological processes. In this study, forty-eight male mice were randomly divided into four groups (n = 12): Control (fed normal rice), Cu300 (300 mg/kg copper), Cu300+Se (Cu300 + selenium-enriched rice), and Cu300+iSe (Cu300 + 1 mg/kg iSe), and were treated for 180 days. Copper exposure resulted in reduced body weight, hepatomegaly and nephritis, elevated copper deposition in organs, oxidative stress, and significant declines in RBC, HGB, and WBC counts, leading to anemia and immunosuppression. Selenium supplementation, effectively mitigated these effects by reducing copper accumulation, restoring antioxidant balance, and enhancing selenoprotein-related functions. Histopathological analysis revealed that copper toxicity induced hydropic degeneration and focal necrosis in hepatic and renal tissues, effects that were significantly attenuated by selenium supplementation. Transcriptomic profiling revealed that selenium-enriched rice reversed copper-induced gene expression changes. In the liver, selenium treatment significantly upregulated protective genes such as Slc7a, Bola1, Uqcrq, Dtx1, and Znrd2, while downregulating stress-related genes like Trim75, Dpm3, Moxd1, Tnfrsf25, and Gpr75. In the kidneys, selenium enhanced the expression of detoxification and immune-modulating genes (Mt1, Mt2, Rhbdl1, Crisp3, Mif) and suppressed stress-related genes (Nnt, Ifi44l, NLRP12, Eno1b, Ugt1a), demonstrating its role in mitigating oxidative and inflammatory stress. Collectively, these findings demonstrate that selenium-enriched rice exerts potent protective effects against chronic copper toxicity through multiple mechanisms: (1) restoration of mitochondrial function, (2) attenuation of ER stress and apoptosis, (3) enhancement of antioxidant and detoxification pathways, and (4) modulation of metabolic and immune responses. This study highlights selenium-enriched rice as a promising nutritional intervention for mitigating chronic copper toxicity and maintaining hepatorenal health. Full article

Autoimmune kidney diseases (AIKDs) are a consequence of the dysregulation of immune response and the loss of tolerance to self-antigens, which led to glomerulonephritis and tissue damage. Autoantibody-producing B cells, as well as T cells, neutrophils and macrophages play a pivotal role in the pathogenesis and progression of various AIKDs. In recent years, B cell-depleting/modulating therapies and molecules that modulate T cell differentiation pathways and cytokine production have become a new hope for patients with immune-mediated kidney diseases. However, these biologicals often do not bring satisfactory therapeutic benefits, which is most likely related to incomplete B cell depletion of tissue-resident B cells. A new hope is immunotherapy with chimeric antigen receptor (CAR) effector cells. In CAR therapy, immune cells (mostly T cells) are genetically modified to express a CAR, which enables the recognition of the specific antigen on a target cell. This interaction leads to the formation of immune synapse and cytotoxicity. CAR-based strategies are a potent form of cell therapy that offers a better chance for deep and durable response than other recently approved immune therapies. Moreover, CAR-T cells can be programmed for higher precision and safety. This review explores the current landscape of CAR-T cell therapy in AIKDs. Full article

Hyperuricemia, characterized by elevated serum uric acid levels, is a major risk factor for gout and kidney disease. This study evaluated the antihyperuricemic effects of Cornus officinalis extract (COE) using urate transporter 1 (URAT1)-expressing oocytes and a hyperuricemia rat model. COE effectively inhibited uric acid absorption by modulating URAT1, with an IC₅₀ value of 3.24 µg/mL. In the hyperuricemia model, COE administration (100 and 200 mg/kg) significantly reduced serum uric acid levels and increased urinary uric acid excretion. The primary constituents of COE, morroniside (MO) and loganin (LO) exerted similar effects, with MO exhibiting potent inhibition of uric acid absorption even at low concentrations. Kidney tissue analysis revealed a reduction in blood urea nitrogen (BUN) levels, indicating improved renal function. Liver function parameters (ALT, AST, and LDH) remained unchanged, suggesting an absence of hepatotoxicity. Ultra-high-performance liquid chromatography with charged aerosol detection (UHPLC-CAD) analysis identified MO (17.8 mg/g), LO (9.8 mg/g), and cornin (1.4 mg/g) as the principal components of COE. These findings suggest that COE enhances uric acid excretion via URAT1 regulation and exerts renoprotective effects, highlighting its potential as an antihyperuricemic agent. Furthermore, MO and LO were identified as the primary active constituents, and COE appears to be a promising therapeutic candidate with a favorable safety profile. Full article

Radiation is widely used in cancer therapy but also damages healthy tissues through oxidative stress or inflammation. In addition to cancer patients, many professionals are occupationally exposed to ionizing radiation (IR). Natural compounds, particularly polyphenols, have been increasingly investigated as potential radioprotective agents to minimize side effects in both patients and occupationally exposed individuals. This study evaluated the radioprotective effects of a polyphenol-rich extract blend derived from chokeberry, elderberry, blackcurrant, and evening primrose in female Balb/c mice exposed to acute IR. The animals were pre-treated with the blend (100 mg/kg) for 7 days prior to whole-body IR at 6 Gy. Hematological parameters, immune cell viability, TNF-α level, gene expression, lipid peroxidation, and tissue morphology were assessed by hematology analysis, flow cytometry, ELISA, qRT-PCR, MDA assay, and histology. IR significantly reduced leukocyte (3.22-fold; p < 0.0001) and platelet counts (1.37-fold; p < 0.0001), increased TNF-α levels (53.93%; p < 0.0001), and elevated oxidative stress. Pre-treatment with the blend restored hematological parameters, reduced pro-inflammatory cytokines, and normalized genes regulating oxidative stress and apoptosis. Histology confirmed preserved liver and kidney structures compared with irradiated controls. These findings highlight the polyphenol-rich extract blend as a promising natural radioprotective agent by modulating immune responses, reducing oxidative stress, and preserving tissue integrity. Full article

Acute kidney injury (AKI) is a frequent clinical and pathological condition, often resulting from factors like ischemia, toxins, or infections, which cause a sudden and severe decline in renal function. This, in turn, significantly affects patients’ overall health and quality of life. The Sirtuin family (SIRTs), a group of Nicotinamide Adenine Dinucleotide (NAD+)-dependent deacetylases, is critically involved in key biological processes such as cellular metabolism, stress responses, aging, and DNA repair. Recent research has highlighted the vital role of SIRTs, such as SIRT1, SIRT3, and SIRT6, in the development and progression of AKI. These proteins help mitigate renal injury and facilitate kidney repair through mechanisms like antioxidant activity, anti-inflammatory responses, cellular repair, and energy metabolism. Additionally, the deacetylase activity of the SIRTs confers protection against AKI by modulating mitochondrial function, decreasing oxidative stress, and regulating autophagy. Although the precise mechanisms underlying the role of Sirtuins in AKI are still being explored, their potential as therapeutic targets is increasingly being recognized. This paper will discuss the mechanisms by which the SIRTs influence AKI and examine their potential in a future therapeutic strategy. Full article

P2Y₂ receptors are a subclass of G protein-coupled receptors activated by the extracellular nucleotides ATP and UTP. These receptors are widely expressed in multiple tissues—including the brain, lungs, heart, and kidneys—and play pivotal roles in inflammation, wound healing, and cell migration. Through coupling with various G proteins, P2Y₂ receptors initiate diverse intracellular signaling pathways that mediate calcium mobilization, cytokine release, and cytoskeletal reorganization. Recent studies highlight their dual roles in health and disease. In physiological contexts, P2Y₂ receptors contribute to immune modulation and tissue repair. In pathological conditions, they are implicated in Alzheimer’s disease by promoting non-amyloidogenic processing of amyloid precursor protein and in dry eye disease by enhancing mucin secretion while modulating ocular inflammation. They also influence chloride secretion and mucosal hydration in cystic fibrosis and contribute to inflammatory regulation and epithelial repair in inflammatory bowel disease. Additionally, P2Y₂ receptors modulate breast cancer progression by regulating cell adhesion, migration, and matrix remodeling. Their involvement in blood pressure regulation via epithelial sodium channel modulation and their facilitative role in HIV-1 entry further underscore their clinical significance. These multifaceted functions position P2Y₂ receptors as promising therapeutic targets for diverse diseases, warranting further investigation for translational applications. Full article

The nitric oxide (NO) pathway is a fundamental regulator of vascular tone, myocardial function, and inflammation. In heart failure (HF), especially in advanced stages, dysregulation of NO–soluble guanylate cyclase (sGC)–cyclic guanosine monophosphate (cGMP) signaling contributes to endothelial dysfunction, increased vascular resistance, myocardial fibrosis, and impaired cardiac performance. Chronic inflammation further reduces NO bioavailability, exacerbating HF progression This review synthesizes current knowledge on the role of the NO pathway in HF pathophysiology, with a focus on stable and advanced HF. Special attention is given to patient subgroups with comorbidities such as chronic kidney disease, where modulation of NO signaling may be particularly beneficial. We also evaluate therapeutic strategies targeting NO bioavailability and sGC stimulation. Evidence shows that impaired NO signaling promotes systemic and pulmonary vasoconstriction, elevates ventricular afterload, and worsens cardiac remodeling. Pharmacological agents that restore NO levels or activate downstream effectors such as sGC improve vasodilation, reduce fibrosis, and enhance myocardial relaxation. These effects are especially relevant in advanced HF patients and those with renal impairment, who often exhibit limited responses to conventional therapies. The NO pathway represents a promising therapeutic target in both stable and advanced HF. Modulating this pathway could improve outcomes, particularly in complex populations with multiple comorbidities, highlighting the need for further clinical research and tailored treatments. Full article

Sepsis is a life-threatening condition driven by a dysregulated host response to infection, with high mortality and few treatment options. Decades of failed drug development underscore the urgent need for therapies with novel mechanisms of action. Vimentin, an intermediate filament protein, acts as a network hub that senses and integrates cellular signals. Its involvement in key sepsis pathologies, including infection, hyperinflammation, immunosuppression, coagulopathy and metabolic dysregulation, positions it as a potential therapeutic target. This study evaluated the efficacy of ALD-R491, a novel small-molecule vimentin modulator, in a murine model of polymicrobial sepsis induced by cecal ligation and puncture (CLP). Mice received ALD-R491 prophylactically or therapeutically, alone or with ceftriaxone. The treatment significantly reduced serum levels of key biomarkers of sepsis, including C-reactive protein (CRP), lactate (Lac), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), and dose-dependently improved the survival of septic mice. Organ-specific analysis confirmed the effects of ALD-R491 in mitigating hyperinflammation and multi-organ injury. The treatment reduced pulmonary edema and inflammation; preserved liver tissue architecture and improved hepatic function with lowered alanine aminotransferase/aspartate aminotransferase (ALT/AST); decreased kidney tubular damage; and improved renal function with lowered creatinine/blood urea nitrogen (BUN). These preclinical findings indicate that the vimentin-targeting agent ALD-R491 represents a promising therapeutic candidate for sepsis and merits further clinical investigation. Full article