👤 Sakshi Rai

The aging process is associated with gradual cognitive decline resulting from deficits in synaptic plasticity, the brain's natural ability to adapt and reshape its neural circuitry. This review highlights the importance of synaptic plasticity in cognitive function. It provides a full overview of the molecular, cellular, and systemic mechanisms involved in enhanced or diminished synaptic plasticity in the aging brain. We also go over issues in neurotransmitter systems, calcium signaling, neurotrophic support (ex., BDNF-TrkB), cellular signaling pathways (e.g. mTOR, CaMK, CREB, and MAPK/ERK), and neuroinflammation, oxidative stress, and vascular integrity, all of which redirect the trajectory of synaptic failure associated with cognitive decline in aging. Therapeutic approaches toward increasing or restoring synaptic plasticity are evaluated, including pharmacological (e.g., nootropics, cholinesterase inhibitors, NMDA receptor modulators), natural (e.g., curcumin, resveratrol, bacoside A), and new interventions (e.g., psychoplastogens, gene therapy, nanocarriers, and digital therapeutics). Lifestyle approaches, especially physical exercise, cognitive training, intermittent fasting, and mindfulness approaches to stimulation, have highly potent effects on plasticity enhancements and employ multiple neurobiological mechanisms. Despite much promise, there remain substantial translational challenges, including limited clinical efficacy, lack of personalized biomarkers, and ethical considerations concerning cognitive enhancement. As we look ahead, a multidisciplinary integrative approach that includes molecular therapeutics, lifestyle interventions, and next-generation neurotechnologies will be most useful for protecting cognitive health and enhancing brain resilience in aging individuals. This review highlights the immediate necessity for personalized, ethical, and evidence-based approaches to take advantage of synaptic plasticity for healthy cognitive aging. Show less

Apolipoprotein E (APOE) regulates lipid metabolism and neuronal repair, yet its alleles show contrasting effects on hemorrhagic stroke (HS) risk. While some variants increase susceptibility, others appear protective, leading to inconsistent findings. This meta-analysis systematically evaluates the APOE-HS association to clarify its role in stroke pathophysiology. A comprehensive literature search was conducted across multiple databases up to January 31, 2025, using the keywords: ("Apolipoprotein E" OR "APOE" OR "APOE genotype") AND ("Single Nucleotide Polymorphisms" OR "SNP") AND ("Hemorrhagic stroke" OR "HS" OR "Intracerebral Hemorrhage" OR "ICH"). The APOE ε3/ε3 genotype served as the reference genotype in all studies, and only those studies with ε3/ε3 genotype were included in the analysis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and statistical analyses were performed using STATA version 13.0 (StataCorp LLC, College Station, Texas, United States). A total of 24 studies comprising 8,269 HS patients and 26,321 controls were included. Meta-analysis revealed a significant association of APOE ε2/ε2 (OR = 1.93, 95% CI = 1.32-2.81), ε4/ε4 (OR = 1.60, 95% CI = 1.21-2.13), ε2/ε4 (OR = 1.81, 95% CI = 1.34-2.44), ε2 (OR = 1.23, 95% CI = 1.12-1.35), and ε4 (OR = 1.31, 95% CI = 1.14-1.51) with an increased risk of HS. Our findings suggest that APOE ε2/ε2, ε2/ε4, ε2, and ε4/ε4 genotypes and the ε4 allele are associated with an elevated risk of HS. These results highlight the potential role of APOE genotypes in HS susceptibility and warrant further investigation. Show less

Neurodegenerative disorders such as Alzheimer's disease (AD) are characterized by progressive neuronal degeneration, predominantly caused by the accumulation of amyloid-beta (Aβ) and neuroinflammatory processes. Hypoxia, characterized by diminished oxygen levels, intensifies these mechanisms by stimulating hypoxia-inducible factor 1-alpha (HIF-1α), potentially enhancing BACE1 enzyme activity and resulting in increased Aβ synthesis and render neurons especially susceptible to hypoxia, exacerbating disease progression. Existing therapies are constrained by inadequate medication distribution across the blood-brain barrier and associated adverse effects. This study aims to identify potential therapeutic agents targeting HIF-1 We used Results identified several compounds with strong binding affinities and favorable ADMET profiles as potential inhibitors of HIF-1 Show less

Alzheimer's disease (AD), a primary cause of dementia, involves cognitive decline and neuroinflammation. Human hair follicle stem cells (hHFSCs) have shown neuroprotective potential, but their effects on immune modulation, especially in xenogeneic transplantation, remain unclear. This study aimed to investigate the therapeutic potential of hHFSCs against memory impairment and neuroinflammation induced by streptozotocin (STZ) in male rats. Adult male Sprague-Dawley rats were intracerebroventricularly injected with STZ (3 mg/kg) to induce AD-like cognitive deficits. hHFSC transplantation (1 × 10 STZ significantly impaired memory in passive avoidance test, but not Y-maze. hHFSC significantly improved memory performance. mRNA analysis revealed elevated BDNF, TGFβ, and GFAP levels in the STZ group. The increased TGFβ and GFAP levels continued following hHFSC treatment, indicating a compensatory response. Moreover, pro-inflammatory factors (IL-1β, IL-6, and TNFα) were upregulated following hHFSC therapy, suggesting persistent neuroinflammation. hHFSC led to anti-inflammatory effects through the elevation of IL-10. In addition, hHFSCs significantly reduced hippocampal atrophy and neuronal loss induced by STZ. hHFSCs exhibit partial neuroprotective effects against STZ-induced memory impairment. The simultaneous upregulation of pro- and anti-inflammatory markers underscores the complexity of the inflammatory response in this xenogeneic model. Future investigations should consider immunocompromised models or immunosuppressive protocols better to isolate the therapeutic effects of hHFSCs from immune responses. Show less

First-line immune checkpoint inhibitor (ICI) combinations show responses in subsets of hepatocellular carcinoma (HCC) patients. Nearly half of HCCs are Wnt-active with mutations in CTNNB1 (encoding for β-catenin), AXIN1/2, or APC, and demonstrate heterogeneous and limited benefit to ICI due to an immune excluded tumor microenvironment. We show significant tumor responses in multiple β-catenin-mutated immunocompetent HCC models to a novel siRNA encapsulated in lipid nanoparticle targeting CTNNB1 (LNP-CTNNB1). Both single-cell and spatial transcriptomics reveal cellular and zonal reprogramming, along with activation of immune regulatory transcription factors IRF2 and POU2F1, re-engaged type I/II interferon signaling, and alterations in both innate and adaptive immunity upon β-catenin suppression with LNP-CTNNB1 at early- and advanced-stage disease. Moreover, ICI enhances response to LNP-CTNNB1 in advanced-stage disease by preventing T cell exhaustion and through formation of lymphoid aggregates (LA). In fact, expression of an LA-like gene signature prognosticates survival for patients receiving atezolizumab plus bevacizumab in the IMbrave150 phase III trial and inversely correlates with CTNNB1-mutatational status in this patient cohort. In conclusion, LNP-CTNNB1 is efficacious as monotherapy and in combination with ICI in CTNNB1-mutated HCCs through impacting tumor cell-intrinsic signaling and remodeling global immune surveillance, providing rationale for clinical investigations. Show less

Therapeutic effects of the bioactive compounds obtained from three common plants against the human combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) was explored in silico. These phytoconstituents Show less

Activation of incretin receptors by their cognate agonist augments sustained cAMP generation both from the plasma membrane as well as from the endosome. To address the functional outcome of this spatiotemporal signaling, we developed a nonacylated glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor dual agonist I-M-150847 that reduced receptor internalization following activation of the incretin receptors. The incretin receptor dual agonist I-M-150847 was developed by replacing the tryptophan cage of exendin-4 tyrosine substituted at the amino terminus with the C-terminal undecapeptide sequence of oxyntomodulin that placed lysine 30 of I-M-150847 in frame with the corresponding lysine residue of GIP. The peptide I-M-150847 is a partial agonist of GLP-1R and GIPR; however, the receptors, upon activation by I-M-150847, undergo reduced internalization that promotes agonist-mediated iterative cAMP signaling and augments glucose-stimulated insulin exocytosis in pancreatic β cells. Chronic administration of I-M-150847 improved glycemic control, enhanced insulin sensitivity, and provided profound weight loss in diet-induced obese (DIO) mice. Our results demonstrated that despite being a partial agonist, I-M-150847, by reducing the receptor internalization upon activation, enhanced the incretin effect and reversed obesity. Show less

The classical swine fever virus (CSFV) particle consists of three glycoproteins, all of which have been shown to be important proteins involved in many virus functions, including interaction with several host proteins. One of these proteins, E2, has been shown to be directly involved with adsorption to the host cell and important for virus virulence. Using the yeast two-hybrid system, we have previously shown that CSFV E2 specifically interacts with the (DOCK7) dedicator of cytokinesis, a scaffolding protein. In this report, the interaction between E2 and DOCK7 was evaluated. To confirm the yeast two-hybrid results and to determine that DOCK7 interacts in swine cells with E2, we performed co-immunoprecipitation and proximity ligation assay (PLA). After demonstrating the protein interaction in swine cells, E2 amino acid residues Y65, V283, and T149 were determined to be critical for interaction with Dock7 by using a random mutated library of E2 and a reverse yeast two-hybrid approach. That disruption of these three residues with mutations Y65F, V283D, and T149A abrogated the Dock7-E2 protein interaction. These mutations were then introduced into a recombinant CSFV, E2DOCK7v, by a reverse genomics approach using the highly virulent CSFV Brescia isolate as a backbone. E2DOCKv was shown to have similar growth kinetics in swine primary macrophages and SK6 cell cultures to the parental Brescia strain. Similarly, E2DOCK7v demonstrated a similar level of virulence to the parental Brescia when inoculated in domestic pigs. Animals intranasally inoculated with 10 Show less

Label free shotgun proteomics was used to analyse plasma and Longissimus muscle biopsies of Limousin-sired bulls, classified as 5 high-quality and 5 low-quality meat based on sensory texture traits (tenderness, juiciness and chewiness). A total of 31 putative protein biomarkers (16 in plasma and 15 in muscle) differed significantly in abundance between the two quality groups. The proteins were associated with muscle structure, energy metabolism, heat shock proteins, oxidative stress and proteolysis related pathways. Among them, B2M, AHSG, APOA4 and HP-20 (plasma), PFKM, MYH2, PTER, GSTM1 and MYPN (muscle) were good predictors of the three texture quality traits. Further, significant correlations were identified for FETUB, SERPINA7, ASL, TREH, HP, HP-25, AZGP1, APCS and SYT15, which are novel biomarkers from plasma that warrant further evaluation. This study is a significant step forward in elucidating proteomic profiles in bovine bio-fluids and muscle tissue, which may ultimately provide opportunities to processors for early assessment of beef sensory quality. Show less

Venous thrombo-embolism (VTE) is multi-factorial disease involving several genetic and acquired risk factors responsible for its onset. It may occur spontaneously upon climbing at High Altitude (HA). Several studies demonstrated that hypoxic conditions prevailing at HA pose an independent risk factor for VTE; however, molecular mechanism remains unknown. Present study aims to identify genes associated with HA-induced VTE pathophysiology using real time TaqMan Low-Density Array (TLDA) of known candidate genes. Gene expression of total 93 genes were studied and analyzed in patients of VTE from HA (HA-VTE) and from sea level (SL-VTE) in comparison to respective controls. Both HA-VTE and SL-VTE patients showed up-regulation of 37 genes involved in blood coagulation cascade, clot formation, platelet formation, endothelial response, angiogenesis, cell adhesion and calcium channel activity. Seven genes including ACE, EREG, C8A, DLG2, USF1, F2 and PCDHA7 were up-regulated in both HA-controls and VTE patients (both HA-VTE and SL-VTE) indicating their role during VTE event and also upon HA exposure. Ten genes; CDH18, FGA, EDNBR, GATA2, MAPK9, BCAR1, FRK, F11, PCDHA1 and ST8SIA4 were uniquely up-regulated in HA-VTE. The differentially expressed genes from the present study could be determining factors for HA-VTE susceptibility and provide insights into VTE occurrence at HA. Show less

Prostate stem/progenitor cells (PrSCs) are responsible for adult prostate tissue homeostasis and regeneration. However, the related regulatory mechanisms are not completely understood. In this study, we examined the role of heparan sulfate (HS) in PrSC self-renewal and prostate regeneration. Using an in vitro prostate sphere formation assay, we found that deletion of the glycosyltransferase exostosin 1 (Ext1) abolished HS expression in PrSCs and disrupted their ability to self-renew. In associated studies, we observed that HS loss inhibited p63 and CK5 expression, reduced the number of p63+- or CK5+-expressing stem/progenitor cells, elevated CK8+ expression and the number of differentiated CK8+ luminal cells and arrested the spheroid cells in the G1/G0 phase of cell cycle. Mechanistically, HS expressed by PrSCs (in cis) or by neighboring cells (in trans) could maintain sphere formation. Furthermore, HS deficiency upregulated transforming growth factor β (TGFβ) signaling and inhibiting TGFβ signaling partially restored the sphere-formation activity of the HS-deficient PrSCs. In an in vivo prostate regeneration assay, simultaneous loss of HS in both epithelial cell and stromal cell compartments attenuated prostate tissue regeneration, whereas the retention of HS expression in either of the two cellular compartments was sufficient to sustain prostate tissue regeneration. We conclude that HS preserves self-renewal of adult PrSCs by inhibiting TGFβ signaling and functions both in cis and in trans to maintain prostate homeostasis and to support prostate regeneration. Show less

The polymorphic alleles of APOA5 (rs2266788 (C), rs3135506 (G)), LPA (rs10455872 (A), rs3798220 (G)) and 9p21.3 (rs1333049 (C), rs2383207(A)) have been reported in association with susceptibility of coronary artery disease (CAD) from genome wide association studies. We aimed to assess the association of genetic variants with coronary angiogram proven CAD, severity scored with modified Gensini score and association of risk for myocardial infraction (MI) in North Indian population. We recruited 512 angiographic proven CAD patients (mean age 58.1±10.2years) and 272 controls (mean age 50.3±11.1years) with normal coronaries from North Indian population. The genotyping technique polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was employed for rs2266788, rs3135506 and rs10455872. Amplified refractory mutation system-PCR (ARMS-PCR) was used for genotyping of rs1333049, rs2383207 and rs3798220 genetic variants. The polymorphic risk allele of variants rs2266788 (C), rs1333049 (C), rs2383207 (A) and heterozygous polymorphic alleles of rs2266788 (TC) were significantly associated with CAD. The homozygous alleles of rs22667788 (CC) and rs1333049 (CC) had also been significantly associated with CAD. The significance of association of rs2266788 (C, CC, TC) and rs1333049 (C, CC) increases with severity of CAD. The presence of mutant allele of rs2266788 (C) was associated with risk of MI and unstable angina (UA). Also, homozygous risk allele of rs2266788 (CC) significantly associated with risk of MI and UA in patients of chronic stable angina (CSA) patients. Whereas, the risk allele of rs1333049 (C) have shown the association with MI and UA compared to controls. The genetic variants of rs3135506 (G), rs10455872 (A) and rs3798220 (G) have low frequency in our population and reflected no association with CAD. The polymorphic variants of Apo-A5; rs2266788 (C), 9p21.3; rs1333049 (C) rs2383207 (A) are associated with CAD, its severity and exerts the risk of MI in North Indian population. Show less

Reduced expression of the p53 family member p63 has been suggested to play a causative role in cancer metastasis. Here, we show that ΔNp63α, the predominant p63 isoform, plays a major role in regulation of cell migration, invasion and cancer metastasis. We identified mitogen-activated protein (MAP) kinase phosphatase 3 (MKP3) as a downstream target of ΔNp63α that is required for mediating these effects. We show that ΔNp63α regulates extracellular signal-regulated protein kinases 1 and 2 (Erk1/2) activity via MKP3 in both cancer and non-transformed cells. We further show that exogenous ΔNp63α inhibits cell invasion and is dependent on MKP3 upregulation for repression. Conversely, endogenous pan-p63 ablation results in increased cell migration and invasion, which can be reverted by reintroducing the ΔNp63α isoform alone, but not by other isoforms. Interestingly, these effects require Erk2, but not Erk1 expression, and can be rescued by enforced MKP3 expression. Moreover, MKP3 expression is reduced in invasive cancers, and reduced p63 expression increases metastatic frequency in vivo. Taken together, these results suggest an important role for ΔNp63α in preventing cancer metastasis by inhibition of Erk2 signaling via MKP3. Show less

The bone morphogenetic protein antagonist Gremlin 2 (Grem2) is required for atrial differentiation and establishment of cardiac rhythm during embryonic development. A human Grem2 variant has been associated with familial atrial fibrillation, suggesting that abnormal Grem2 activity causes arrhythmias. However, it is not known how Grem2 integrates into signaling pathways to direct atrial cardiomyocyte differentiation. Here, we demonstrate that Grem2 expression is induced concurrently with the emergence of cardiovascular progenitor cells during differentiation of mouse embryonic stem cells (ESCs). Grem2 exposure enhances the cardiogenic potential of ESCs by 20-120-fold, preferentially inducing genes expressed in atrial myocytes such as Myl7, Nppa, and Sarcolipin. We show that Grem2 acts upstream to upregulate proatrial transcription factors CoupTFII and Hey1 and downregulate atrial fate repressors Irx4 and Hey2. The molecular phenotype of Grem2-induced atrial cardiomyocytes was further supported by induction of ion channels encoded by Kcnj3, Kcnj5, and Cacna1d genes and establishment of atrial-like action potentials shown by electrophysiological recordings. We show that promotion of atrial-like cardiomyocytes is specific to the Gremlin subfamily of BMP antagonists. Grem2 proatrial differentiation activity is conveyed by noncanonical BMP signaling through phosphorylation of JNK and can be reversed by specific JNK inhibitors, but not by dorsomorphin, an inhibitor of canonical BMP signaling. Taken together, our data provide novel mechanistic insights into atrial cardiomyocyte differentiation from pluripotent stem cells and will assist the development of future approaches to study and treat arrhythmias. Show less

Gallbladder cancer (GBC) is a violent neoplasm associated with late diagnosis, unsatisfactory treatment, and poor prognosis. The disease shows complex interplay between multiple genetic variants. We analyzed 15 polymorphisms in nine genes involved in various pathways to find out combinations of genetic variants contributing to GBC risk. The genes included in the study were matrix metalloproteinases (MMP-2, MMP-7, and MMP-9), tissue inhibitor of metalloproteinases (TIMP-2), cytochrome P450 (CYP)1A1, CYP1B1, phospholipase C epsilon 1 (PLCE1), liver X receptor (LXR)-alpha, and LXR-beta. Genotypes were determined by PCR-RFLP and TaqMan probes. Statistical analysis was done by SPSS version 16. Multilocus analysis was performed by Classification and Regression Tree (CART) analysis and multifactor dimensionality reduction (MDR) to gene-gene interactions in modifying GBC risk. In silico analysis was done using various bioinformatics tools (F-SNP, FAST-SNP). Single locus analysis showed association of MMP-2 (-735 C > T, -1306 C > T), MMP-7 - 181 A > G, MMP-9 (P574R, R668Q), TIMP-2 - 418 G > C, CYP1A1-MspI, CYP1A1-Ile462Val, PLCE1 (rs2274223 A > G, rs7922612 T > C) and LXR-beta T > C (rs3546355 G > A, rs2695121 T > C) polymorphisms with GBC risk (p < 0.05) whereas CYP1B1 and LXR-α variants were not associated with GBC risk. Multidimensional reduction analysis revealed LXR-β (rs3546355 G > A, rs2695121 T > C), MMP-2 (-1306 C > T), MMP-9 (R668Q), and PLCE1 rs2274223 A > G to be key players in GBC causation (p < 0.001, CVC = 7/10). The results were further supported by independent CART analysis (p < 0.001). In silico analysis of associated variants suggested change in splicing or transcriptional regulation. Interactome and STRING analysis showed network of associated genes. The study found PLCE1 and LXR-β network interactions as important contributory factors for genetic predisposition in gallbladder cancer. Show less

Heparan sulfate (HS) has been implicated in regulating cell fate decisions during differentiation of embryonic stem cells (ESCs) into advanced cell types. However, the necessity and the underlying molecular mechanisms of HS in early cell lineage differentiation are still largely unknown. In this study, we examined the potential of EXT1(-/-) mouse ESCs (mESCs), that are deficient in HS, to differentiate into primary germ layer cells. We observed that EXT1(-/-) mESCs lost their differentiation competence and failed to differentiate into Pax6(+)-neural precursor cells and mesodermal cells. More detailed analyses highlighted the importance of HS for the induction of Brachyury(+) pan-mesoderm as well as normal gene expression associated with the dorso-ventral patterning of mesoderm. Examination of developmental cell signaling revealed that EXT1 ablation diminished FGF and BMP but not Wnt signaling. Furthermore, restoration of FGF and BMP signaling each partially rescued mesoderm differentiation defects. We further show that BMP4 is more prone to degradation in EXT1(-/-) mESCs culture medium compared with that of wild type cells. Therefore, our data reveal that HS stabilizes BMP ligand and thereby maintains the BMP signaling output required for normal mesoderm differentiation. In summary, our study demonstrates that HS is required for ESC pluripotency, in particular lineage specification into mesoderm through facilitation of FGF and BMP signaling. Show less

Heart failure is a leading cause of mortality in South Asians. However, its genetic etiology remains largely unknown. Cardiomyopathies due to sarcomeric mutations are a major monogenic cause for heart failure (MIM600958). Here, we describe a deletion of 25 bp in the gene encoding cardiac myosin binding protein C (MYBPC3) that is associated with heritable cardiomyopathies and an increased risk of heart failure in Indian populations (initial study OR = 5.3 (95% CI = 2.3-13), P = 2 x 10(-6); replication study OR = 8.59 (3.19-25.05), P = 3 x 10(-8); combined OR = 6.99 (3.68-13.57), P = 4 x 10(-11)) and that disrupts cardiomyocyte structure in vitro. Its prevalence was found to be high (approximately 4%) in populations of Indian subcontinental ancestry. The finding of a common risk factor implicated in South Asian subjects with cardiomyopathy will help in identifying and counseling individuals predisposed to cardiac diseases in this region. Show less