👤 Pankhuri Singhal

Niemann-Pick disease, type C1 (NPC1), is a rare, fatal, neurodegenerative lysosomal disorder caused by pathological variants in Proximal Extension Assays (PEA) were used to determine relative protein expression levels from 68 serum samples from NPC1 individuals and 20 age-appropriate control serum samples. Statistical models identified NPC1 disease-specific effects after adjusting for covariates. Selected proteins were orthogonally validated by ELISA and correlated with assessments of both disease severity (Age of Neurological Onset (ANO) and Annual Severity Increment Score (ASIS)) and disease burden (NPC Neurological Severity Score (NSS). Quantifiable data was obtained on 2888 proteins, revealing 186 increased (adjusted log The statistical analysis pipeline developed in this study is flexible and scalable and supports application to high-dimensional proteomic datasets. This study identified and validated serum proteins with altered expression in individuals with NPC1, responded to miglustat therapy, and correlated with disease severity or burden. These proteins may have clinical utility as biomarkers and provide insights into cellular mechanisms contributing to NPC1 disease pathology. NCT00344331 (Registration on 2006-06-23). Show less

We recently demonstrated the utility of the 'TB Concentration & Transport' kit for bio-safe, ambient-temperature transport of dried sputum samples on Trans-Filter, along with the 'TB DNA Extraction' kit for efficient DNA extraction from Trans-Filter for use in the Line Probe Assay (LPA) for diagnosing drug-resistant tuberculosis (TB). The present study aimed to develop and evaluate a new 'Quick TB DNA Extraction' kit ('Quick DNA' kit) for rapid DNA isolation from Trans-Filter samples and assess its compatibility with LPA for the detection of multidrug-resistant TB (MDR-TB). Consecutive presumptive TB/MDR-TB/XDR-TB patients (n = 1823) were screened using LED-FM and/or TBDetect microscopy at 2 Designated Microscopy Centres associated with the National Institute of Tuberculosis and Respiratory Diseases (NITRD), New Delhi. Smear-positive samples (n = 235) were processed in duplicate using the 'TB Concentration and Transport' kit. Dried sputum on bio-safe Trans-Filters was transported at ambient temperature, along with sputum samples, in a 3-layer packing in cooling conditions to NITRD Hospital (a National Reference Laboratory). DNA was extracted from Trans-Filters using 'Quick DNA' kit and the 'TB DNA Extraction' kit, and from sputum using Hain's GenoLyse® DNA Extraction kit for first-line LPA for MDR-TB detection. Quick Kit-LPA and Kit-LPA (LPA with DNA extracted from Trans-Filter using 'Quick DNA' kit and 'TB DNA Extraction' kit, respectively) showed similar sensitivity of 88.9% (95% CI: 65.3-98.6) and 88.5% (95% CI: 69.9-97.5) and specificity of 100% (95% CI: 98.2-100) and 99.5% (95% CI: 97.3-99.9) for rifampicin and isoniazid resistance detection, respectively against Direct-LPA (LPA with DNA extracted from sputum samples using GenoLyse kit). User feedback obtained from laboratory technicians corroborated that the one-step 'Quick DNA' kit procedure was rapid (5 minutes), easy to perform, seamlessly integrated with LPA testing, and was suitable as a replacement for Kit-LPA or Direct-LPA. The gap between drug-resistant TB detection and treatment initiation can be narrowed through Universal-Drug Susceptibility Testing by implementing (i) bio-safe and ambient temperature transport of sputum from primary healthcare centres to central laboratories, and (ii) by using Quick Kit-LPA over Direct-LPA in patients residing in remote areas. Show less

Alzheimer's disease (AD) is a global burden to the healthcare system with no viable treatment options till date. Rodents and primates have been extensively used as models for understanding AD pathogenesis and identifying therapeutic targets. However, the focus is now shifting towards developing alternate models. Zebrafish is emerging as a preferred model for neurodegenerative conditions because of its simple nervous system, highly conserved genome and short duration required to model disease condition. The present study is aimed to develop streptozotocin (STZ)-induced model of sporadic AD (sAD) in zebrafish. STZ was administered to adult zebrafish (4-6 mo) at different doses (1 to 50 mg/kg body weight, intracerebroventricularly). Kaplan-Meier survival analysis revealed time and dose dependent mortality in the zebrafish administered with STZ. Based on survival analysis, 1 to 10 mg/kg body weight of STZ was selected for behavioural, molecular and histological studies. STZ administered fish had anxiety-like and stress behaviour in novel tank and light/dark preference tests. STZ-induced cognitive and memory deficits assessed using novel object recognition and spatial alternation tests. Further, expression of markers of amyloidogenic pathway (appa and bace1) were increased in terms of mRNA and protein levels in a time and dose dependent manner following STZ administration. However, expression of non-amyloidogenic pathway mediator (adam10) was reduced at both mRNA and protein level. Histological assessment using hematoxylin and eosin, and Nissl stain revealed loss of neurons in STZ administered fish. The ratio of phosphor-tau Show less

Heart failure is a complex trait, influenced by environmental and genetic factors, affecting over 30 million individuals worldwide. Here we report common-variant and rare-variant association studies of all-cause heart failure and examine how different classes of genetic variation impact its heritability. We identify 176 common-variant risk loci at genome-wide significance in 2,358,556 individuals and cluster these signals into five broad modules based on pleiotropic associations with anthropomorphic traits/obesity, blood pressure/renal function, atherosclerosis/lipids, immune activity and arrhythmias. In parallel, we uncover exome-wide significant associations for heart failure and rare predicted loss-of-function variants in TTN, MYBPC3, FLNC and BAG3 using exome sequencing of 376,334 individuals. We find that total burden heritability of rare coding variants is highly concentrated in a small set of Mendelian cardiomyopathy genes, while common-variant heritability is diffusely spread throughout the genome. Finally, we show that common-variant background modifies heart failure risk among carriers of rare pathogenic truncating variants in TTN. Together, these findings discern genetic links between dysregulated metabolism and heart failure and highlight a polygenic component to heart failure not captured by current clinical genetic testing. Show less

PALS1-associated tight junction (PATJ) protein is linked to metabolic disease and stroke in human genetic studies. Despite the recognized role of PATJ in cell polarization, its specific functions in metabolic disease and ischemic stroke recovery remain largely unexplored. We explored the functions of PATJ in an in vitro model and in vivo in C. elegans and mice. Using a mouse model of stroke, we found post-ischemic stroke duration-dependent increase of PATJ abundance in endothelial cells. PATJ knock-out (KO) HEK293 cells generated by CRISPR-Cas9 suggest roles for PATJ in cell proliferation, migration, mitochondrial stress response, and interactions with the Yes-associated protein (YAP)-1 signaling pathway. Notably, PATJ deletion altered YAP1 nuclear translocation. PATJ KO cells demonstrated transcriptional reprogramming based on RNA sequencing analysis, and identified dysregulation in genes central to vascular development, stress response, and metabolism, including RUNX1, HEY1, NUPR1, and HK2. Furthermore, we found that mpz-1, the homolog of PATJ, was significantly upregulated under hypoxic conditions in C. elegans. Knockdown of mpz-1 resulted in abnormal neuronal morphology and increased mortality, both of which were exacerbated by hypoxia exposure, indicating a critical protective role of PATJ/MPZ-1 in maintaining neuronal integrity and survival, particularly during oxygen deprivation stress relevant to ischemic stroke. These insights offer a new understanding of PATJ's regulatory functions within cellular and vascular physiology and help lay the groundwork for therapeutic strategies targeting PATJ-mediated pathways for stroke rehabilitation and neurovascular repair. Show less

Heart failure (HF) is a complex trait, influenced by environmental and genetic factors, which affects over 30 million individuals worldwide. Historically, the genetics of HF have been studied in Mendelian forms of disease, where rare genetic variants have been linked to familial cardiomyopathies. More recently, genome-wide association studies (GWAS) have successfully identified common genetic variants associated with risk of HF. However, the relative importance of genetic variants across the allele-frequency spectrum remains incompletely characterized. Here, we report the results of common- and rare-variant association studies of all-cause heart failure, applying recently developed methods to quantify the heritability of HF attributable to different classes of genetic variation. We combine GWAS data across multiple populations including 207,346 individuals with HF and 2,151,210 without, identifying 176 risk loci at genome-wide significance (P-value < 5×10 Show less

The uncommon, benign dysembryoplastic neuroepithelial tumor (DNET, WHO grade 1) is frequently linked to epilepsy. It is a glioneuronal neoplasm in the cerebral cortex of children or young adults defined by the presence of a pathognomonic glioneuronal element that may be linked to glial nodules and activating mutations of fibroblast growth factor receptor 1 ( Show less

Primary tumors and distant site metastases form a bidirectionally communicating system. Yet, the molecular mechanisms of this crosstalk are poorly understood. Here, we identified the proteolytically cleaved fragments of angiopoietin-like 4 (ANGPTL4) as contextually active protumorigenic and antitumorigenic contributors in this communication ecosystem. Preclinical studies in multiple tumor models revealed that the C-terminal fragment (cANGPTL4) promoted tumor growth and metastasis. In contrast, the N-terminal fragment of ANGPTL4 (nANGPTL4) inhibited metastasis and enhanced overall survival in a postsurgical metastasis model by inhibiting WNT signaling and reducing vascularity at the metastatic site. Tracing ANGPTL4 and its fragments in tumor patients detected full-length ANGPTL4 primarily in tumor tissues, whereas nANGPTL4 predominated in systemic circulation and correlated inversely with disease progression. The study highlights the spatial context of the proteolytic cleavage-dependent pro- and antitumorigenic functions of ANGPTL4 and identifies and validates nANGPTL4 as a novel biomarker of tumor progression and antimetastatic therapeutic agent. Show less

Recent genome-wide association scans (GWAS) and meta-analysis studies on European populations have identified many genes previously implicated in lipid regulation. Validation of these loci on different global populations is important in determining their clinical relevance, particularly for development of novel drug targets for treating and preventing diabetic dyslipidemia and coronary artery disease (CAD). In an attempt to replicate GWAS findings on a non-European sample, we examined the role of six of these loci (CELSR2-PSRC1-SORT1 rs599839; CDKN2A-2B rs1333049; BUD13-ZNF259 rs964184; ZNF259 rs12286037; CETP rs3764261; APOE-C1-C4-C2 rs4420638) in our Asian Indian cohort from the Sikh Diabetes Study (SDS) comprising 3,781 individuals (2,902 from Punjab and 879 from the US). Two of the six SNPs examined showed convincing replication in these populations of Asian Indian origin. Our study confirmed a strong association of CETP rs3764261 with high-density lipoprotein cholesterol (HDL-C) (p = 2.03×10(-26)). Our results also showed significant associations of two GWAS SNPs (rs964184 and rs12286037) from BUD13-ZNF259 near the APOA5-A4-C3-A1 genes with triglyceride (TG) levels in this Asian Indian cohort (rs964184: p = 1.74×10(-17); rs12286037: p = 1.58×10(-2)). We further explored 45 SNPs in a ∼195 kb region within the chromosomal region 11q23.3 (encompassing the BUD13-ZNF259, APOA5-A4-C3-A1, and SIK3 genes) in 8,530 Asian Indians from the London Life Sciences Population (LOLIPOP) (UK) and SDS cohorts. Five more SNPs revealed significant associations with TG in both cohorts individually as well as in a joint meta-analysis. However, the strongest signal for TG remained with BUD13-ZNF259 (rs964184: p = 1.06×10(-39)). Future targeted deep sequencing and functional studies should enhance our understanding of the clinical relevance of these genes in dyslipidemia and hypertriglyceridemia (HTG) and, consequently, diabetes and CAD. Show less