👤 Sonu Chand Thakur

Lower-extremity arterial disease (LEAD) is a manifestation of atherosclerotic cardiovascular disease, affecting 230 million people worldwide with increasing prevalence. Medial arterial calcification (MAC) is common in LEAD patients and contributes to disease-related mortality. However, therapeutic strategies targeting femoral MAC are lacking, and its underlying mechanisms remain unclear. This study aimed to identify molecular drivers of femoral MAC in LEAD. Calcium deposits and pro-calcifying markers were analyzed in human patient samples using von Kossa staining, immunofluorescence, and gene expression analysis. Femorals showed significantly more calcification and pro-calcifying gene expression than carotids. Given MAC abundance in LEAD, we assessed medial calcification in Apoe-/- mice fed a WD for 4/21 weeks. Digital PCR revealed upregulation of Ddr1 and Bmp2 in femoral versus carotid arteries after 21 weeks of WD. DDR1 expression positively correlated with calcification in human femoral samples. In vitro experiments with mouse femoral vs. carotid vascular smooth muscle cells (VSMCs) confirmed a significantly higher prevalence of calcifying proteins (DDR1, BMP2, and RUNX2) in femoral VSMCs. Additionally, calcification analyses in murine and human VSMCs showed that DDR1 inhibition reduced, while DDR1 activation increased, calcium deposition. Transcriptomic analysis revealed elevated NF-κB expression in human femoral arteries, matching data in femoral VSMCs. DDR1 stimulation activated NF-κB, and its inhibition blocked DDR1-induced calcification. This study identifies DDR1 as a key driver of calcification in LEAD, operating through NF-κB activation and the expression of calcifying proteins. Targeting DDR1 may offer a novel therapeutic approach to prevent MAC in LEAD. Show less

Alzheimer's disease (AD) is a debilitating neurodegenerative condition characterized by progressive cognitive impairment, memory deterioration, and neuronal dysfunction. Its complex pathophysiology involves multiple interlinked processes, including amyloid-β (Aβ) aggregation, tau hyperphosphorylation, oxidative stress, neuroinflammation, synaptic dysfunction, and cholinergic deficits. Current FDA-approved therapies provide only symptomatic relief and fail to halt disease progression, highlighting the urgent need for more effective treatment strategies. This review provides a comprehensive overview of the pathological mechanisms underlying AD and the emerging therapeutic targets for the design of tractable anti-AD scaffolds, namely, acetylcholinesterase, beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), glycogen synthase kinase-3β (GSK3β), dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A), histone deacetylases (HDACs), and soluble epoxide hydrolase (sEH). Emphasis is placed on the paradigm shift from single-target therapies to multitarget-directed ligands (MTDLs), which are increasingly recognized as promising tools to tackle AD's multifactorial pathology. We also discuss recent advances in medicinal chemistry and structure-guided drug discovery campaigns aimed at developing pharmacologically optimized, BBB-penetrant MTDLs. By consolidating mechanistic insights with therapeutic innovation, this review aims to facilitate the development of next-generation therapeutics with enhanced efficacy and disease-modifying potential in AD. Show less

Visceral leishmaniasis, caused by the protozoan parasite Leishmania donovani is one of the most life threatening neglected tropical disease with no licensed human vaccine and increasing risks of resistance to chemotherapeutic agents. Current vaccine approaches are hindered by suboptimal immunogenecity, underscoring the need for potent adjuvant that can steer a durable and protective immune response. Here, we reported for the first time immunotherapeutic potential of a synthetic TLR7/8 agonist, 1-(4-(aminomethyl)benzyl)-2-butyl-1H-imidazo[4,5-c]quinolin-4 aminedihydrochloride (p-AM-BBIQ), in combination with heat-killed L. donovani antigen (HKA) in a murine model. Mice immunized with the adjuvanted formulation exhibited significant reduction in splenic parasite load, alongside enhanced production of nitric oxide and reactive oxygen species. Trancriptional profiling revealed increased upregulation of iNOS and Nf-κB, indicating activation of innate immune response. Flow cytometric analysis demonstrated increased frequencies of CD4 Show less

Alzheimer's disease (AD) is a complex neurodegenerative disorder having limited treatment options. The beta-site APP cleaving enzyme 1 (BACE-1) is a key target for therapeutic intervention in Alzheimer's disease. To discover new scaffolds for BACE-1 inhibitors, a ChemBridge DIVERSet library of 20,000 small molecules was employed to structure-based virtual screening. The top 45 compounds, based on docking scores and binding affinities, were tested for BACE-1 inhibitory activity using a FRET assay. Four compounds, 18 (5353320), 20 (5262831), 29 (5784196) and 32 (5794006) demonstrated more than 35 % inhibitory activity at 10 μM. Notably, pyrazole-5-carbohydrazide 29 (5784196) exhibited BACE-1 inhibition with an IC Show less

The relation between hepatic ChREBP level and insulin sensitivity remains equivocal. Our study, however, provides compelling evidence that hepatic ChREBP depletion can significantly enhance insulin sensitivity in high-fat and sucrose-fed mice. We have identified that transcriptional induction of hepatic PTEN is driven by ChREBP. Mechanistically, two critical stimuli are elicited in the hepatic ChREBP knockdown condition. The PTEN level is reduced for one stimulus, thereby promoting hepatic insulin sensitivity. The second stimulus, where reduced hepatic PTEN leads to the enhanced release of FGF21, spreads systemic insulin sensitivity. These findings identify hepatic ChREBP as a critical modulator of systemic insulin signaling and suggest that ChREBP downregulation may lead to protection against insulin resistance. Building on this, our molecular dynamics simulation analysis has led to the discovery of a small molecule, Quercetin, that sequesters ChREBP in the cytosol. We report that Quercetin treatment can sequester ChREBP in the cytosol and abrogate high-fat and sucrose-fed-mediated ChREBP nuclear translocation, thereby mimicking the insulin-sensitizing abilities of the hepatic ChREBP knockdown condition. These findings have significant therapeutic implications, suggesting that liver-selective downregulation of ChREBP could protect against systemic insulin resistance that frequently develops early in the pathogenesis of NAFLD and T2DM. Show less

Congenital heart disease (CHD) is associated with neurodevelopmental and cognitive impairments, but the underlying molecular mechanisms remain unclear. This study investigated cardiac neuronal genomics in CHD using single-nucleus RNA-sequencing data (GSE203274) from 157,273 cardiac nuclei of healthy donors and patients with hypoplastic left heart syndrome (HLHS), Tetralogy of Fallot (TOF), dilated (DCM), and hypertrophic (HCM) cardiomyopathies. The Uniform Manifold Approximation and Projection (UMAP) clustering identified major cardiac cell types, revealing neuron-specific transcriptional programmes. Neuronal populations showed enriched expression of neurodevelopmental disorder-linked genes ( Show less

Amphiregulin (AREG) stimulates human epithelial ovarian cancer (EOC) cell invasion by downregulating E-cadherin expression. YAP is a transcriptional cofactor that has been shown to regulate tumorigenesis. This study aimed to examine whether AREG activates YAP in EOC cells and explore the roles of YAP in AREG-induced downregulation of E-cadherin and cell invasion. Analysis of the Cancer Genome Atlas (TCGA) showed that upregulation of AREG and EGFR were associated with poor survival in human EOC. Treatment of SKOV3 human EOC cells with AREG induced the activation of YAP. In addition, AREG downregulated E-cadherin, upregulated Egr-1 and Slug, and stimulated cell invasion. Using gain- and loss-of-function approaches, we showed that YAP was required for the AREG-upregulated Egr-1 and Slug expression. Furthermore, YAP was also involved in AREG-induced downregulation of E-cadherin and cell invasion. This study provides evidence that AREG stimulates human EOC cell invasion by downregulating E-cadherin expression through the YAP/Egr-1/Slug signaling. Show less

Alzheimer's disease (AD) is an advancing neurodegenerative disorder distinguished by the formation of amyloid plaques and neurofibrillary tangles in the human brain. Nevertheless, the lack of peripheral biomarkers that can detect the development of AD remains a significant limitation. The main aim of this work was to discover the molecular markers associated with AD. We conducted a comprehensive microarray analysis of gene expression data from hippocampus tissue in AD patients and control samples using three microarray datasets (GSE1297, GSE28146, and GSE29378) collected from Gene Expression Omnibus (GEO). The datasets were pre-processed and normalized, revealing 346 significant genes, 103 of which were upregulated and 243 downregulated. The PPI network of significant genes was constructed to detect the top 50 hub genes, which were then further analyzed using Gene Ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes pathway (KEGG), and GSEA, revealing 47 key genes involved in AD-related pathways. These key genes were then subjected to feed forward loop (FFL) motif analysis for the prediction of transcriptional factors (TFs) and microRNAs (miRNAs) mediated gene regulatory networks. The interaction of AD-associated TFs HNF4A, SPI1, EGR1, STAT3, and MYC and miRNAs hsa-miR-155-5p and hsa-miR-16-5p in the transcriptional and post-transcriptional events of 3 upregulated and 10 downregulated genes: H2AFZ, MCM3, MYO1C, AXIN1, CCND1, ETS2, MYH9, RELA, RHEB, SOCS3, TBL1X, TBP, TXNIP, and YWHAZ, respectively, has been identified. The miRNA/TF-mediated three types of the FFL motifs, i.e., miRNA-FFL, TF-FFL, and composite-FFL, were constructed, and seven common genes among these FFL were identified: CCND1, MYH9, SOCS3, RHEB, MYO1C, TXNIP, AXIN1, and TXNIP. These findings may provide insights into the development of potential molecular markers for therapeutic management of AD. Show less

A potential role for fibroblast growth factor receptor 2 (FGFR2) in cutaneous squamous cell carcinoma (cSCC) has been reported. To demonstrate the specific role of FGFR2 in UVB-induced skin carcinogenesis and development of cSCC, we generated a keratinocyte specific, tamoxifen inducible mouse model of FGFR2 deficiency. In this mouse model, topical application of 4-hydroxy tamoxifen led to the induction of Cre recombinase to delete FGFR2 in epidermal keratinocytes of both male and female transgenic mice. Analysis of epidermal protein lysates isolated from FGFR2 deficient mice exposed to UVB showed significant reductions of phospho-FGFR (pFGFR; Y653/654) and phospho-fibroblast growth factor receptor substrate 2α as well as downstream effectors of mTORC1 signaling. Phosphorylation of signal transducer and activators of transcription 1/3 was significantly reduced as well as levels of IRF-1, DUSP6, early growth response 1, and PD-L1 compared to the control groups. Keratinocyte-specific ablation of FGFR2 also significantly inhibited epidermal hyperproliferation, hyperplasia, and inflammation after exposure to UVB. Finally, keratinocyte-specific deletion of FGFR2 significantly inhibited UVB-induced cSCC formation. Collectively, the current data demonstrate an important role of FGFR2 in UVB-induced oncogenic signaling as well as development of cSCC. In addition, the current preclinical findings suggest that inhibition of FGFR2 signaling may provide a previously unreported strategy to prevent and/or treat UVB-induced cSCC. Show less

The complex and multifaceted nature of Alzheimer's disease has brought about a pressing demand to develop ligands targeting multiple pathways to combat its outrageous prevalence. Embelin is a major secondary metabolite of Show less

Milk fat composition is an important trait for the dairy industry as it directly influences the nutritional and technological properties of milk and other dairy products. The synthesis of milk fat is a complex process regulated by a network of genes. Thus, understanding the genetic variation and molecular mechanisms regulating milk fat synthesis will help to improve the nutritional quality of dairy products. In this review, we provide an overview of milk fat synthesis in bovines along with the candidate genes involved in the pathway. We also discuss de novo synthesis of fatty acids (ACSS, ACACA, FASN), uptake of FAs (FATP, FAT, LPL), intracellular activation and channelling of FAs (ACSL, FABP), elongation (EVOLV6), desaturation (SCD, FADS), formation of triglycerides (GPAM, AGPAT, LIPIN, DGAT), and milk lipid secretion (BTN1A1, XDH, PLIN2). The genetic variability of individual fatty acids will help to develop selection strategies for obtaining a healthier milk fat profile in bovines. Thus, this review will offer a potential understanding of the molecular mechanisms that regulate milk fat synthesis in bovines. Show less

Benign prostatic hyperplasia (BPH) is a commonly occurring disease in aging men. It involves cellular proliferation of stromal and glandular tissues leading to prostate enlargement. Current drug therapies show several adverse effects such as sexual dysfunctions and cardiovascular side effects. Therefore, there is a need to develop more effective medical treatment for BPH. In this regard, we aimed to identify genes which play a critical role in BPH. We have obtained the dataset of differentially expressed genes (DEGs) of BPH from NCBI GEO. DEGs were investigated in the context of their protein-protein interactions (PPI). Hub genes i.e. genes associated with BPH were scrutinized based on the topological parameters of the PPI network. These were analyzed for functional annotations, pathway enrichment analysis and transcriptional regulation. In total, 38 hub genes were identified. Hub genes such as transcription factor activator protein-1 and adiponectin were found to play key roles in cellular proliferation and inflammation. Another gene peroxisome proliferator activated receptor gamma was suggested to cause obesity, a common comorbidity of BPH. Moreover, our results indicated an important role of transforming growth factor-beta (TGF-β) signaling and smooth muscle cell proliferation which may be responsible for prostate overgrowth and associated lower urinary tract symptoms frequently encountered in BPH patients. Zinc finger protein Snai1 was the most prominent transcription factor regulating the expression of hub genes that participate in TGF-β signaling. Overall, our study has revealed significant hub genes that can be employed as drug targets to develop potential therapeutic interventions to treat BPH. Show less

Insufficient invasion of trophoblast cells into the uterine decidua is associated with preeclampsia (PE). G protein-coupled estrogen receptor (GPER) is a membrane estrogen receptor involved in non-genomic estrogen signaling. GPER is expressed in human trophoblast cells and downregulated GPER levels are noted in PE. However, to date, the role of GPER in trophoblast cells remains largely unknown. Here, we applied RNA sequencing (RNA-seq) to HTR-8/SVneo human trophoblast cells in response to G1, an agonist of GPER, and identified angiopoietin-like 4 (ANGPTL4) as a target gene of GPER. Treatment of trophoblast cells with G1 or 17β-estradiol (E2) activated Yes-associated protein (YAP), the major downstream effector of the Hippo pathway, via GPER but in a mammalian STE20-like protein kinase 1 (MST1)-independent manner. Using pharmacological inhibitors as well as loss- and gain-of-function approaches, our results revealed that YAP activation was required for GPER-stimulated ANGPTL4 expression. Transwell invasion assays demonstrated that activation of GPER-induced ANGPTL4 promoted cell invasion. In addition, the expression levels of GPER, YAP, and ANGPTL4 were downregulated in the placenta of patients with PE. Our findings reveal a mechanism by which GPER exerts its stimulatory effect on human trophoblast cell invasion by upregulating YAP-mediated ANGPTL4 expression. Show less

Many bacteria have the potential to use specific pesticides as a source of carbon, phosphorous, nitrogen and sulphur. Acephate degradation by microbes is considered to be a safe and effective method. The overall aim of the present study was to identify acephate biodegrading microorganisms and to investigate the degradation rates of acephate under the stress of humic acid and most common metal ions Fe(III) and copper Cu(II). Show less

Concentric and eccentric cardiac hypertrophy are associated with pressure and volume overload, respectively, in cardiovascular disease both conferring an increased risk of heart failure. These contrasting forms of hypertrophy are characterized by asymmetrical growth of the cardiac myocyte in mainly width or length, respectively. The molecular mechanisms determining myocyte preferential growth in width versus length remain poorly understood. Identification of the mechanisms governing asymmetrical myocyte growth could provide new therapeutic targets for the prevention or treatment of heart failure. Primary adult rat ventricular myocytes, adeno-associated virus (AAV)-mediated gene delivery in mice, and human tissue samples were used to define a regulatory pathway controlling pathological myocyte hypertrophy. Chromatin immunoprecipitation assays with sequencing and precision nuclear run-on sequencing were used to define a transcriptional mechanism. We report that asymmetrical cardiac myocyte hypertrophy is modulated by SRF (serum response factor) phosphorylation, constituting an epigenomic switch balancing the growth in width versus length of adult ventricular myocytes in vitro and in vivo. SRF Ser We have identified a new molecular switch, namely mAKAPβ signalosome-regulated SRF phosphorylation, that controls a transcriptional program responsible for modulating changes in cardiac myocyte morphology that occur secondary to pathological stressors. Complementary AAV-based gene therapies constitute rationally-designed strategies for a new translational modality for heart failure. Show less

Myocyte enhancer factor 2 (MEF2) transcription factors are key regulators of the development and adult phenotype of diverse tissues, including skeletal and cardiac muscles. Controlled by multiple post-translational modifications, MEF2D is an effector for the Ca Show less

Class IIa histone deacetylases (HDACs) are transcriptional repressors whose nuclear export in the cardiac myocyte is associated with the induction of pathological gene expression and cardiac remodeling. Class IIa HDACs are regulated by multiple, functionally opposing post-translational modifications, including phosphorylation by protein kinase D (PKD) that promotes nuclear export and phosphorylation by protein kinase A (PKA) that promotes nuclear import. We have previously shown that the scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) orchestrates signaling in the cardiac myocyte required for pathological cardiac remodeling, including serving as a scaffold for both PKD and PKA. We now show that mAKAPβ is a scaffold for HDAC5 in cardiac myocytes, forming signalosomes containing HDAC5, PKD, and PKA. Inhibition of mAKAPβ expression attenuated the phosphorylation of HDAC5 by PKD and PKA in response to α- and β-adrenergic receptor stimulation, respectively. Importantly, disruption of mAKAPβ-HDAC5 anchoring prevented the induction of HDAC5 nuclear export by α-adrenergic receptor signaling and PKD phosphorylation. In addition, disruption of mAKAPβ-PKA anchoring prevented the inhibition by β-adrenergic receptor stimulation of α-adrenergic-induced HDAC5 nuclear export. Together, these data establish that mAKAPβ signalosomes serve to bidirectionally regulate the nuclear-cytoplasmic localization of class IIa HDACs. Thus, the mAKAPβ scaffold serves as a node in the myocyte regulatory network controlling both the repression and activation of pathological gene expression in health and disease, respectively. Show less

Cardiac myocyte hypertrophy is the main compensatory response to chronic stress on the heart. p90 ribosomal S6 kinase (RSK) family members are effectors for extracellular signal-regulated kinases that induce myocyte growth. Although increased RSK activity has been observed in stressed myocytes, the functions of individual RSK family members have remained poorly defined, despite being potential therapeutic targets for cardiac disease. To demonstrate that type 3 RSK (RSK3) is required for cardiac myocyte hypertrophy. RSK3 contains a unique N-terminal domain that is not conserved in other RSK family members. We show that this domain mediates the regulated binding of RSK3 to the muscle A-kinase anchoring protein scaffold, defining a novel kinase anchoring event. Disruption of both RSK3 expression using RNA interference and RSK3 anchoring using a competing muscle A-kinase anchoring protein peptide inhibited the hypertrophy of cultured myocytes. In vivo, RSK3 gene deletion in the mouse attenuated the concentric myocyte hypertrophy induced by pressure overload and catecholamine infusion. Taken together, these data demonstrate that anchored RSK3 transduces signals that modulate pathologic myocyte growth. Targeting of signaling complexes that contain select kinase isoforms should provide an approach for the specific inhibition of cardiac myocyte hypertrophy and for the development of novel strategies for the prevention and treatment of heart failure. Show less