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Biology subjects

Thanaraj, T. A.

Publications and source records attributed to Thanaraj, T. A..

4 recordsLinked to original sources

Conserved Cardiovascular Network: Bioinformatics Insights into Genes and Pathways for Establishing Caenorhabditis elegans as an Animal Model for Cardiovascular Diseases.

Cardiovascular disease (CVD) is a collective term for disorders of the heart and blood vessels. The molecular events and biochemical pathways associated with CVD are difficult to study in clinical settings on patients and in vitro conditions. Animal models play a pivotal and indispensable role in cardiovascular disease (CVD) research. Caenorhabditis elegans, a nematode species, has emerged as a prominent experimental organism widely utilised in various biomedical research fields. However, the specific number of CVD-related genes and pathways within the C. elegans genome remains undisclosed to date, limiting its in-depth utilisation for investigations. In the present study, we conducted a comprehensive analysis of genes and pathways related to CVD within the genomes of humans and C. elegans through a systematic bioinformatic approach. A total of 1113 genes in C. elegans orthologous to the most significant CVD-related genes in humans were identified, and the GO terms and pathways were compared to study the pathways that are conserved between the two species. In order to infer the functions of CVD-related orthologous genes in C. elegans, a PPI network was constructed. Orthologous gene PPI network analysis results reveal the hubs and important KRs: pmk-1, daf-21, gpb-1, crh-1, enpl-1, eef-1G, acdh-8, hif-1, pmk-2, andaha-1 in C. elegans. Modules were identified for determining the role of the orthologous genes at various levels in the created network. We also identified 9 commonly enriched pathways between humans and C. elegans linked with CVDs that include autophagy (animal), the ErbB signalling pathway, the FoxO signalling pathway, the MAPK signalling pathway, ABC transporters, the biosynthesis of unsaturated fatty acids, fatty acid metabolism, glutathione metabolism, and metabolic pathways. This study provides the first systematic genomic approach to explore the CVD-associated genes and pathways that are present in C. elegans, supporting the use of C. elegans as a prominent animal model organism for cardiovascular diseases.

bioinformatics↗

Glucose intolerance induces anxiety-like behaviors independent of obesity and insulin resistance in a novel model of nutritional metabolic stress

Type 2 diabetes (T2D) and its comorbidities are a major public health concern. In addition to peripheral tissues, T2D also impacts the central nervous system leading to neurocognitive impairments, including memory deficits, anxiety, and depression. The metabolic determinants of these neurocognitive impairments remain unidentified. Here, we used a novel proprietary high-fat diet, in which glucose intolerance precedes weight gain, to decipher the metabolic determinants of neurocognitive affects. We show that this model exhibits anxiety-like behaviors, without eliciting depression nor recognition memory deficits. Long-term feeding leads to weight gain, brain glucose hypometabolism and impaired recognition memory alongside the early onset anxiety-like behavior. Using an established genetic model of T2D (db/db) and of diet-induced obesity we show that additional insulin resistance and obesity are associated with depressive-like behaviors and recognition memory deficits. Our findings indicate that glucose intolerance alone can elicit anxiety-like behaviors. Through this study we also provide a novel nutritional model to characterize the discrete effects of glucose intolerance on cognition, behavior, and the physiology of metabolic disease.

animal behavior and cognition↗

ANGPTL8 R59W variant influences inflammation through modulating NF-κB pathway under TNFα stimulation

BackgroundANGPTL8 is known to regulate lipid metabolism and inflammation. It interacts with ANGPTL3 and ANGPTL4 to regulate LPL activity, and with IKK/{beta} to modulate NF-{kappa}B activity. Further, a SNP leading to ANGPTL8 R59W variant associates with reduced LDL/HDL and increased FBG in Hispanic and Arab individuals, respectively. In this study, we investigate the impact of R59W variant on the inflammatory activity of ANGPTL8. MethodsANGPTL8 R59W variant was genotyped in a discovery cohort of 867 Arab individuals from Kuwait. Plasma levels of ANGPTL8 and inflammatory markers were measured and tested for associations with the genotype; the associations were tested for replication in an independent cohort of 278 Arab individuals. Impact of the ANGPTL8 R59W variant on NF-{kappa}B activity was examined using approaches including overexpression, luciferase assay, and structural modeling of binding dynamics. ResultsThe ANGPTL8 R59W variant was associated with increased circulatory levels of TNF and IL7. NF-{kappa}B activity, as assessed by the increased in the phosphorylation of IKK-/{beta} protein, I{kappa}B, and NF-{kappa}B p-65 in R59W variant compared to wild type, and TNF stimulation further elevated it. This finding was substantiated by increased luciferase activity of NF-{kappa}B p65 with the R59W variant. Modeled structural and binding variation due to R59W change in ANGPTL8 agreed with the observed increase in NF-{kappa}B activity. ConclusionANGPTL8 R59W is associated with increased circulatory TNF, IL7 and NF-{kappa}B p65 activity. Weak transient binding of ANGPTL8 R59W variant explains its regulatory role on the NF-{kappa}B pathway and inflammation.

biochemistry↗

Genome-wide selection scan in the Kuwaiti population identifies a TNKS haplotype linked to metabolic traits and hypertension

Despite the extreme and varying environmental conditions prevalent in the Arabian Peninsula, it has experienced several waves of human migrations following the out-of-Africa diaspora. Eventually, the inhabitants of the peninsula region adapted to the hot and dry environment. The adaptation and natural selection that shaped the extant human populations of the Arabian Peninsula region have been scarcely studied. In an attempt to explore natural selection in the region, we analyzed 662,750 variants in 583 Kuwaiti individuals. We searched for regions in the genome that display signatures of positive selection in the Kuwaiti population using an integrative approach in a conservative manner. We highlight a haplotype overlapping TNKS that showed strong signals of positive selection based on the results of the multiple selection tests conducted (integrated Haplotype Score, Cross Population Extended Haplotype Homozygosity, Population Branch Statistics, and log-likelihood ratio scores). Notably, the TNKS haplotype under selection potentially conferred a fitness advantage to the Kuwaiti ancestors for surviving in the harsh environment while posing a major health risk to present-day Kuwaitis.

evolutionary biology↗