Search Results (210)

Vitamin C, also known as L-ascorbic acid (AA), functions as a pro-oxidant in cancer at high doses and exerts anticancer effects by generating reactive oxygen species (ROS) and selectively inducing damage to cancer cells. However, AA at low doses promotes cancer cell proliferation. The efficacy of high-dose AA therapy is frequently restricted by inadequate intracellular AA uptake, resulting from low expression of sodium-dependent vitamin C transporter 2 (SVCT2). In this study, we investigated whether valproic acid (VPA), a histone deacetylase inhibitor, could circumvent this constraint by increasing the expression of SVCT2 in colorectal cancer cells, including HCT-116 and DLD-1 with low SVCT2 levels. We found that VPA increased SVCT2 expression in both cell lines. Co-treatment with AA and VPA increased the number of apoptotic cells and enhanced intracellular AA uptake via VPA-upregulated SVCT2, followed by increased ROS production in both cell lines. Furthermore, the combination increased the synergistic anticancer effects and suppressed the hormetic dose response of AA in both cell lines. In a xenograft mouse model, co-treatment decreased tumor size and increased the tumor growth inhibition ratio compared to treatment with AA or VPA alone. Accordingly, VPA treatment enhanced SVCT2 expression in colorectal cancer cells, suppressed the hormetic dose-response effect of AA, and improved the potential of high-dose AA therapy as an anticancer agent. Full article

Oxidative stress, which contributes to neuronal cell dysfunction, is a critical factor in the pathogenesis of neurodegenerative diseases. Anthocyanins and α-tocopherol have shown potential in mitigating oxidative damage, and their combination may provide synergistic effects. This study investigated the combined effects of a cyanidin-3-glucoside (C3G)-enriched extract derived from Oryza sativa L. cv. RD83 and α-tocopherol (C3GE) on hydrogen peroxide (H₂O₂)-induced oxidative stress in SH-SY5Y cells. Cells were treated with C3GE during exposure to 200 µM H₂O₂. Cell viability, intracellular reactive oxygen species (ROS), and oxidative stress biomarkers, including the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), as well as malondialdehyde (MDA) levels, were evaluated. Protein expression levels of histone deacetylase 1 (HDAC1), nuclear factor erythroid 2 related factor 2 (Nrf2), heme oxygenase 1 (HO-1), and SOD1 were also assessed. The combined treatment markedly improved cell viability, suppressed ROS accumulation, enhanced antioxidant enzyme activities, and significantly reduced MDA levels, suggesting effective protection against oxidative damage. Mechanistically, C3GE downregulated HDAC1 expression while upregulating Nrf2, HO-1, and SOD1, indicating that its antioxidant and neuroprotective effects are mediated, at least in part, through epigenetic modulation of redox-related signaling pathways. These results demonstrate a synergistic interaction between C3G and α-tocopherol that enhances cellular antioxidant defenses and supports redox homeostasis. In conclusion, the C3GE combination offers a promising therapeutic approach for preventing or attenuating oxidative stress-induced neuronal injury, with potential relevance for the treatment of neurodegenerative disorders. Full article

IFI16 is a well-characterized nuclear innate immune DNA sensor that detects foreign dsDNA, including herpesviral genomes, to activate the inflammasome and interferon pathways. Beyond immune signaling, IFI16 also functions as an antiviral restriction factor, promoting the silencing of invading viral genes through transcriptional and epigenetic mechanisms. We recently demonstrated another role of IFI16, in which it interacts with and recruits the class I histone deacetylases, HDAC1 and 2, to the KSHV latency protein LANA, modulating its acetylation and function. In this study, we asked whether these IFI16-HDAC1/2 interactions contribute to broader epigenetic regulation of the KSHV chromatin. Our findings reveal that IFI16 associates with and facilitates the recruitment of the NuRD and Sin3A co-repressor complexes—both multiprotein, HDAC1/2-containing chromatin regulators—on KSHV episomes. Depletion of IFI16 led to reductions in NuRD and Sin3A occupancy on viral chromatin, accompanied by increased histone acetylation at lytic gene promoters. These results suggest that IFI16 plays a critical role in recruiting or stabilizing these HDAC-containing co-repressor complexes on the KSHV genome, thereby enforcing transcriptional silencing of lytic genes and maintaining latency in KSHV. Our study expands the known functions of IFI16 and identifies a novel epigenetic mechanism by which it modulates herpesviral chromatin states. Full article

Background: Breast cancer (BC) is the second most common cancer among women in the United States. It has been estimated that one in eight women will be diagnosed with breast cancer in her lifetime. Various BC risk factors, such as age, physical inactivity, and smoking, play a substantial role in BC occurrence and development. Early life dietary intervention with plant-based bioactive compounds has been studied for its potential role in BC prevention. Sulforaphane (SFN), an isothiocyanate, is an antioxidant and anti-inflammatory agent extracted from broccoli sprouts (BSp) and other plants. Dietary supplementation of SFN suppresses tumor growth by inducing protective epigenetic changes and inhibiting cancer cell proliferation. Inulin, as a dietary fiber, has been studied for alleviating GI discomfort and weight loss by promoting the growth of beneficial bacteria in the gut. Objective: Early-life combinatorial treatment with both phytochemical SFN and potential prebiotic agent inulin at lower and safer dosages may confer more efficacious and beneficial effects in BC prevention. Methods: Transgenic mice representing estrogen receptor-negative BC were fed 26% (w/w) BSp and 2% (w/v) inulin supplemented in food and water, respectively. Results: The combinatorial treatment inhibited tumor growth, increased tumor onset latency, and synergistically reduced tumor weight. Gut microbial composition was analyzed between groups, where Ruminococcus, Muribaculaceae, and Faecalibaculum significantly increased, while Blautia, Turicibacter, and Clostridium sensu stricto 1 significantly decreased in the combinatorial group compared with the control group. Furthermore, combinatorial treatment induced a protective epigenetic effect by inhibiting histone deacetylases (HDACs) and DNA methyltransferases (DNMTs). Intermediates in the AKT/PI3K/MTOR pathway were significantly suppressed by the combinatorial treatment, including PI3K p85, p-AKT, p-PI3K p55, MTOR, and NF-κB. Cell cycle arrest and programmed cell death were induced by the combinatorial treatment via elevating the expression of cleaved-caspase 3 and 7 and inhibiting the expressions of CDK2 and CDK4, respectively. Orally administering F. rodentium attenuated tumor growth and induced apoptosis in a syngeneic triple-negative breast cancer (TNBC) mouse model. Conclusions: Overall, the findings suggest that early-life dietary combinatorial treatment contributed to BC prevention and may be a potential epigenetic therapy that serves as an adjunct to other traditional neoadjuvant therapies. Full article

Defects in lysosomal cholesterol handling provoke fatal disorders presenting neurovisceral symptoms with variable onset and life spans. A prime example is Niemann–Pick type C disease (NPCD), where cholesterol export from the endosomal–lysosomal system is impaired due to variants of either NPC intracellular cholesterol transporter 1 (NPC1) or NPC intracellular cholesterol transporter 2 (NPC2). Therapeutic options for NPCD are limited to palliative care and disease-modifying drugs, and there is a need for new treatments. Here, we explored bromodomain and extra-terminal domain (BET) proteins as new drug targets for NPCD using patient-derived skin fibroblasts. Treatment with JQ1, a prototype BET protein inhibitor, raised the level of NPC1 protein, diminished lysosomal expansion and cholesterol accumulation, and induced extracellular release of lysosomal components in a dose-, time-, and patient-dependent manner. Lastly, JQ1 enhanced and reduced cholesterol accumulation induced by pharmacologic inhibition of NPC1 and of histone deacetylase (HDAC) activity, respectively. Taken together, bromodomain proteins should be further explored as therapeutic drug targets for lysosomal diseases like NPCD, and as new components regulating lysosomal function and cholesterol metabolism. Full article

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia, associated with significant morbidity, mortality, and healthcare burdens. Despite therapeutic advances, recurrence rates remain high, particularly in persistent AF, underscoring the need for deeper mechanistic insight. Epigenetic regulation—comprising DNA methylation, histone modifications, chromatin remodeling, RNA methylation, and non-coding RNAs—has emerged as a key contributor to the structural, electrical, and inflammatory remodeling underlying AF. These mechanisms operate at the interface of genetic susceptibility and environmental exposure, offering a dynamic framework for understanding disease progression. Systemic stressors such as aging, obesity, diabetes, hypertension, hypoxia, and alcohol have been shown to induce epigenetic reprogramming in atrial tissue, further promoting atrial cardiomyopathy and arrhythmogenesis. Additionally, circulating epigenetic markers, particularly microRNAs, are being investigated for their potential in AF diagnosis, risk stratification, and therapeutic monitoring. Therapeutic strategies targeting epigenetic pathways—ranging from histone deacetylase inhibitors and miRNA-based therapeutics to CRISPR/dCas9-mediated epigenome editing—are under investigation. Additionally, sodium-glucose cotransporter 2 inhibitors may indirectly influence epigenetic programs and miRNA expression relevant to atrial remodeling. While promising, these approaches require further validation in terms of safety, delivery specificity, and long-term efficacy. High-resolution epigenomic mapping and integrative multi-omic approaches may enhance understanding of AF heterogeneity and enable personalized treatment strategies. This review provides an integrated appraisal of epigenetic mechanisms in AF and outlines their emerging diagnostic and therapeutic relevance. Full article

As a major global health challenge, hepatocellular carcinoma (HCC) still faces substantial limitations in its treatment options. This study investigates the anti-HCC potential of ACY-1215, a selective Histone deacetylase 6 (HDAC6) inhibitor, and its mechanism targeting p53 regulation. In vitro studies conducted with HepG2 and SMMC-7721 cells revealed that ACY-1215 markedly inhibited HCC cell proliferation, migratory capacity, and invasive potential, as evidenced by CCK-8, colony formation, and Transwell assays. Furthermore, ACY-1215 induced caspase-dependent apoptosis. Mechanistically, ACY-1215 enhanced p53 acetylation by disrupting HDAC6-p53 interaction, thereby stabilizing p53 protein levels. Concurrently, it inhibited Murine Double Minute 2 (MDM2)-mediated ubiquitination, blocking proteasomal degradation and prolonging p53 half-life. This dual modulation restored p53 transcriptional activity, leading to the upregulation of downstream effector molecules associated with cell cycle regulation and apoptosis. Collectively, our findings reveal that ACY-1215 exerts potent anti-HCC effects through coordinated regulation of p53 acetylation and ubiquitination, offering a novel dual-targeting strategy for HCC therapy. Full article

This study investigated whether the supplementation of prebiotic inulin to gestating sows programmatically affects offspring growth performance and meat quality while exploring its epigenetic effects through histone acetylation modulation. After mating, sixty multiparous sows (Landrace × Yorkshire; parity 2–3) were assigned to a 2 × 2 factorial arrangement with inulin (0% vs. 1.5%) and fat (0% or 5%) supplementation until farrowing. Post-weaning, five litters (10 piglets per litter) per treatment were selected and maintained in their original litter for fattening under standardized feeding. The results demonstrated that maternal inulin supplementation during gestation accomplished the following: (1) Increased offspring liver index by 13.4% at weaning and 6.8% at finishing (p < 0.05) while reducing the finishing-phase backfat thickness by 11.6% (p < 0.01), with a significant inulin × fat interaction attenuating fat-induced abdominal lipid accumulation at weaning (p = 0.05). (2) Decreased longissimus dorsi muscle lightness (L*) by 4.5% in finishing pigs (p = 0.02) without altering the other meat quality parameters. (3) Suppressed offspring liver lipid deposition at birth and finishing (p < 0.05), concomitant with upregulated hepatic PGC-1α and CPT1A expression (p < 0.05). (4) Elevated neonatal serum butyrate by 15.6% (p = 0.06) while inhibiting hepatic histone deacetylase (HDAC) activity and enhancing histone H3/H4 acetylation (p < 0.01). These findings suggest that maternal inulin supplementation during gestation mitigates offspring hepatic lipid deposition through butyrate-mediated epigenetic regulation, where microbial-derived butyrate from inulin fermentation inhibits HDAC activity, enhances histone acetylation levels, and upregulates fatty acid β-oxidation gene expression. This study provides novel mechanistic insights into how maternal dietary fiber nutrition programs offspring development through epigenetic reprogramming. Full article

Short-chain fatty acids (SCFAs), mainly produced by gut microbiota through the fermentation process of dietary fibers and proteins, are crucial to human health, with butyrate, a famous four-carbon SCFA, standing out for its inevitably regulatory impact on both gut and immune functions. Within this narrative review, the vital physiological functions of SCFAs were examined, with emphasis on butyrate’s role as an energy source for colonocytes and its ability to enhance the gut barrier while exhibiting anti-inflammatory effects. Knowledge of butyrate synthesis, primarily generated by Firmicutes bacteria, can be influenced by diets with specifically high contents of resistant starches and fiber. Butyrate can inhibit histone deacetylase, modulate gene expression, influence immune functionality, and regulate tight junction integrity, supporting the idea of its role in gut barrier preservation. Butyrate possesses systemic anti-inflammatory properties, particularly, its capacity to reduce pro-inflammatory cytokines and maintain immune homeostasis, highlighting its therapeutic potential in managing dysbiosis and inflammatory diseases. Although butyrate absorption into circulation is typically minimal, its broader health implications are substantial, especially regarding obesity and type 2 diabetes through its influence on metabolic regulation and inflammation. Furthermore, this narrative review thoroughly examines butyrate’s growing recognition as a modulator of neurological health via its interaction with the gut–brain axis. Additionally, butyrate’s neuroprotective effects are mediated through activation of specific G-protein-coupled receptors, such as FFAR3 and GPR109a, and inhibition of histone deacetylases (HDACs). Research indicates that butyrate can alleviate neurological disorders, including Alzheimer’s, Parkinson’s, autism spectrum disorder, and Huntington’s disease, by reducing neuroinflammation, enhancing neurotransmitter modulation, and improving histone acetylation. This focus will help unlock its full therapeutic potential for metabolic and neurological health, rather than exclusively on its well-known benefits for gut health, as these are often interconnected. Full article

The melanoma-associated antigen gene (MAGE) is a key target in cancer immunotherapy. Given the potential of MAGE-B genes in veterinary immunotherapy for canine mammary tumors (CMTs), this study investigated the mRNA expression of MAGE-B1, -B4, -B5, and -B10 in CMT tissues and cells from dogs. Quantitative real-time PCR was used to analyze 28 CMT tissue samples, including 4 benign and 24 malignant tumors (13 simple carcinomas, 6 complex carcinomas, 3 carcinosarcomas, and 2 fibrosarcomas). Benign mixed tumor and complex carcinoma-type CMT cells were cultured and treated with a DNA methylase inhibitor (5-aza-2′-deoxycytidine; 5-aza-CdR) and a histone deacetylase inhibitor (Trichostatin A; TSA) under the following four conditions: (1) 5-aza-CdR for 72 h; (2) TSA for 24 h; (3) 5-aza-CdR for 48 h followed by TSA for 24 h; and (4) control. MAGE-B1 and -B4 showed the highest expression in the CMT samples (100% and 89.29%, respectively), followed by MAGE-B10 (82.14%). Carcinosarcomas and simple anaplastic carcinomas had significantly higher MAGE-B expression levels than simple tubulopapillary carcinomas (p < 0.05). 5-aza-CdR treatment increased MAGE-B expression, whereas TSA had a mild effect. Further research involving larger cohorts is needed to confirm these findings. Full article

Precise binding free-energy predictions for ligands targeting metalloproteins, especially zinc-containing histone deacetylase (HDAC) enzymes, require specialized computational approaches due to the unique interactions at metal-binding sites. This study evaluates a docking algorithm optimized for zinc coordination to determine whether it could accurately differentiate between protonated and deprotonated states of hydroxamic acid ligands, a key functional group in HDAC inhibitors (HDACi). By systematically analyzing both protonation states, we sought to identify which state produces docking poses and binding energy estimates most closely aligned with experimental values. The docking algorithm was applied across HDAC 2, 4, and 8, comparing protonated and deprotonated ligand correlations to experimental data. The results demonstrate that the deprotonated state consistently yielded stronger correlations with experimental data, with R² values for deprotonated ligands outperforming protonated counterparts in all HDAC targets (average R² = 0.80 compared to the protonated form where R² = 0.67). These findings emphasize the significance of proper ligand protonation in molecular docking studies of zinc-binding enzymes, particularly HDACs, and suggest that deprotonation enhances predictive accuracy. The study’s methodology provides a robust foundation for improved virtual screening protocols to evaluate large ligand libraries efficiently. This approach supports the streamlined discovery of high-affinity, zinc-binding HDACi, advancing therapeutic exploration of metalloprotein targets. A comprehensive, step-by-step tutorial is provided to facilitate a thorough understanding of the methodology and enable reproducibility of the results. Full article

Patients carrying APOL1 risk alleles (G1 and G2) have a higher risk of developing Focal Segmental Glomerulosclerosis (FSGS); we hypothesized that escalated levels of miR193a contribute to kidney injury by activating renin–angiotensin system (RAS) in the APOL1 milieus. Differentiated podocytes (DPDs) stably expressing vector (V/DPD), G0 (G0/DPDs), G1 (G1/DPDs), and G2 (G2/DPDs) were evaluated for renin, Vitamin D receptor (VDR), and podocyte molecular markers (PDMMs, including WT1, Podocalyxin, Nephrin, and Cluster of Differentiation [CD]2 associated protein [AP]). G0/DPDs displayed attenuated renin but an enhanced expression of VDR and Wilms Tumor [WT]1, including other PDMMs; in contrast, G1/DPDs and G2/DPDs exhibited enhanced expression of renin but decreased expression of VDR and WT1, as well as other PDMMs (at both the protein and mRNA levels). G1/DPDs and G2/DPDs also showed increased mRNA expression for Angiotensinogen and Angiotensin II Type 1 (AT1R) and 2 (AT2R) receptors. Protein concentrations of Brain Acid-Soluble Protein [BASP]1, Enhancer of Zeste Homolog [EZH]2, Histone Deacetylase [HDAC]1, and Histone 3 Lysine27 trimethylated [H3K27me3] in WT1-IP (immunoprecipitated proteins with WT1 antibody) fractions were significantly higher in G0/DPDs vs. G1/DPD and G2/DPDs. Moreover, DPD-silenced BASP1 displayed an increased expression of renin. Notably, VDR agonist-treated DPDs showed escalated levels of VDR and a higher expression of PDMMs, but an attenuated expression of renin. Human Embryonic Kidney (HEK) cells transfected with increasing APOL1(G0) plasmid concentrations showed a corresponding reduction in renin mRNA expression. Bioinformatics studies predicted the miR193a target sites in the VDR 3′UTR (untranslated region), and the luciferase assay confirmed the predicted sites. As expected, podocytes transfected with miR193a plasmid displayed a reduced VDR and an enhanced expression of renin. Renal cortical section immunolabeling in miR193a transgenic (Tr) mice showed renin-expressing podocytes. Kidney tissue extracts from miR193aTr mice also showed reduced expression of VDR and PDMMs, but enhanced expression of Renin. Blood Ang II levels were higher in miR193aTr, APOLG1, and APOL1G1/G2 mice when compared to control mice. Based on these findings, miR193a regulates the activation of RAS and podocyte molecular markers through modulation of VDR and WT1 in the APOL1 milieu. Full article

Background: Histone deacetylase (HDAC) inhibitors have been reported to exhibit immunomodulatory activities, including the upregulation of major histocompatibility complex class I (MHC class I). Although the immunoproteasome plays a pivotal role in MHC class I antigen presentation, its effect on immunotherapy for clear cell renal cell carcinoma (ccRCC) remains unclear. Methods: This study assessed whether OBP-801, a novel HDAC inhibitor, affects the expression of immunoproteasome subunits and subsequently the MHC class-I-mediated anti-cancer immunity in ccRCC. We analyzed the data of 531 patients with ccRCC from the Cancer Genome Atlas Kidney Clear Cell Carcinoma database. We further evaluated the treatment efficacy of the combination of OBP-801 and anti-PD-1 in a ccRCC mouse model. Results: Low molecular mass polypeptide (LMP) 2 was correlated most positively with CD3E, CD8A, and CD8B expression and estimated CD8⁺ T cell number. In vitro studies showed that OBP-801 upregulated MHC class I presentation by inducing LMP2 expression in the ccRCC cell lines RENCA, 786-O, and Caki-1. In vivo studies in a syngeneic mouse model with subcutaneous implantation of RENCA cells showed that OBP-801 treatment increased the percentage of CD45⁺CD3e⁺ T cells in tumor-infiltrating lymphocytes. The combination of anti-PD-1 antibody and OBP-801 enhanced the anti-tumor effect, LMP2 protein expression, and MHC class I presentation in tumor cells. MHC class I presentation in the tumors of each mouse was positively correlated with the percentage of CD45⁺CD3e⁺ T cells. Conclusions: Our results demonstrate that OBP-801 promotes MHC class I presentation through LMP2 upregulation in tumor cells and thereby potentiates PD-1-targeting therapy. These data suggest that the combination of OBP-801 and anti-PD-1 treatment is a promising therapeutic strategy for ccRCC. Full article

Enhancement of neuronal plasticity by small-molecule therapeutics protects cognitive skills and also ameliorates progressive neurodegenerative pathologies like Alzheimer’s disease (AD) and dementia. One such compound, a novel histone deacetylase 2 (HDAC2) inhibitor named JRM-28, was shown here to enhance dendritic strength, augment spine density, and upregulate post-synaptic neurotransmission in hippocampal neurons. The molecular basis for this effect correlates with JRM-28-induced upregulation of the transcription of cAMP response element-binding protein(CREB), induction of its transcriptional activity, and subsequent stimulation of expressions of CREB-dependent plasticity-associated genes, such as those encoding N-methyl-D-aspartate (NMDA) receptor subunit NR2A and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluR1. Specifically, JRM-28 stimulated the NMDA- and AMPA-receptor-sensitive ionotropic calcium influx in hippocampal neurons. Interestingly, JRM-28 did not induce NMDA- and AMPA-sensitive calcium influx in hippocampal neurons once the expression of CREB was knocked down by creb siRNA, suggesting the critical role of CREB in JRM-28-mediated upregulation of synaptic plasticity. Finally, JRM-28 upregulated CREB mRNA, CREB-dependent plasticity-associated markers, and ionotropic calcium influx in iPSC-derived AD human neurons, indicating its therapeutic implications in the amelioration of AD pathologies. Full article

Multiple sclerosis (MS) is an autoimmune disease mediated by T helper cells, which is characterized by neuroinflammation, axonal or neuronal loss, demyelination, and astrocytic gliosis. Histone deacetylase inhibitors (HDACis) are noted for their roles in easing inflammatory conditions and suppressing the immune response. Panobinostat, an HDACi, is now being used in treating multiple myeloma. Nevertheless, the effect of panobinostat on autoimmune diseases remains largely unclear. Thus, our research endeavored to determine if the administration of panobinostat could prevent experimental autoimmune encephalomyelitis (EAE) in mice, one of the most commonly used animal models of MS, and further explored the underlying mechanisms. The EAE mice were generated and then administered continuously with panobinostat at a dosage of 30 mg/kg for 16 days. The results indicated that panobinostat markedly alleviated the clinical symptoms of EAE mice, inhibiting demyelination and loss of oligodendrocytes in the central nervous system (CNS). Moreover, panobinostat decreased inflammation and the activation of microglia and astrocytes in the spinal cords of EAE mice. Mechanistically, treatment with panobinosat significantly suppressed M1 microglial polarization by blocking the activation of toll-like receptor 2 (TLR2)/myeloid differentiation factor 88 (MyD88)/interferon regulatory factor 5 (IRF5) pathway. Additionally, panobinostat inhibited mitochondrial dysfunction and reduced oxidative stress in the spinal cords of EAE mice. In conclusion, our findings reveal that panobinostat significantly ameliorates experimental autoimmune encephalomyelitis in mice by inhibiting oxidative stress-linked neuroinflammation and mitochondrial dysfunction. Full article