Alzheimer's Disease (AD) is associated with reduced laryngeal sensation, decreased pharyngeal strength, and silent aspiration. Aspiration pneumonia is a leading cause of death in advanced AD. Superior Show more
Alzheimer's Disease (AD) is associated with reduced laryngeal sensation, decreased pharyngeal strength, and silent aspiration. Aspiration pneumonia is a leading cause of death in advanced AD. Superior laryngeal nerve(SLN) dysfunction is hypothesized to be responsible for poor laryngeal sensation and aspiration pneumonia. The purpose of this study was to compare SLN neurophysiology in an AD rat model to control animals. SLN-evoked studies were performed via stimulation of the main trunk in 4-month-old adult apolipoprotein-E4 (ApoE4-KI) rats (n = 8) versus wild-type rats (n = 10). Recording electrodes were placed on the internal branch of the SLN (iSLN) and cricothyroid muscles. Stimulated swallow force measurements from hyoid elevation were compared between groups. Outcome measures included both sensory and motor evoked responses. Additionally, force and frequency of electrically and tactile stimulated swallow reflexes were analyzed. Sensory nerve action potential duration was significantly longer in APOE-KI rats than controls with a mean difference (95% CI) of 2.24 ms (1.08-3.41). Both compound motor action potential latency and total duration were significantly longer in the APOE4-KI rats than controls with a mean difference (95% CI) of 0.22 (0.115-0.33) and 2.18 (0.90-3.4) respectively. Tactile-stimulated swallow frequency was significantly lower in the AD cohort vs. controls with a mean difference of -5.4 swallows/10 s (-7.6, -3.2). SLN evoked responses were significantly longer with a decrease in swallow frequency in an AD rat model compared to age-matched controls. This work suggests differences in SLN signaling between the cohorts. This work may provide a mechanistic understanding of SLN dysfunction and a tractable model to test new treatments for swallow dysfunction. N/A. Show less
The prevalence of Type 2 diabetes mellitus (T2DM) is rapidly increasing in India, yet molecular markers that reflect early disease susceptibility remain limited. Epigenetic modifications such as DNA m Show more
The prevalence of Type 2 diabetes mellitus (T2DM) is rapidly increasing in India, yet molecular markers that reflect early disease susceptibility remain limited. Epigenetic modifications such as DNA methylation may reflect early metabolic vulnerability preceding overt dysglycemia. In this study, we examined genome-wide DNA methylation patterns in a pilot subset nested within a prospective Indian cohort using Nanopore sequencing and assessed their associations with previously identified metabolite predictors from the same cohort. Genome-wide DNA methylation profiling was performed on buffy-coat DNA from 12 participants who were normoglycemic at baseline and later classified into normoglycemia, prediabetes, or T2DM based on their glycemic status at 6-year follow-up. At baseline, gene-level aggregation of CpG methylation revealed directionally consistent hypermethylation of seven genes (ABCG1, ADARB2, BCL2, DLC1, EGFLAM, SYK, ZNF516) in individuals who later developed T2DM, while those progressing to prediabetes exhibited six hypermethylated (ABCG1, FLT3, LCP1, MBP, NCOA2, TCF7L2) and five hypomethylated genes (ZFHX3, PAX6, PTPRN2, ERC1, HIPK1). ABCG1 showed consistent hypermethylation across both groups. Longitudinal within-individual comparisons identified additional gene-associated methylation changes, including ANK1, IQSEC1, and RUNX1, and shared alterations in CACNA1C, KANSL1, PTPRN2, and TTC34, while six genes showed stage-dependent directional shifts in methylation (ASB3, EFR3A, PCSK5, KLHL14, PDE4C, UNC5C). Correlation analyses at baseline suggested associations between ABCG1 and EGFLAM methylation, fasting glucose, phosphatidylethanolamine [PE (20:3₁₈:0)] and insulin sensitivity indices. This pilot longitudinal study suggests that gene-associated DNA methylation changes in blood may be detectable prior to the onset of dysglycemia. These findings are exploratory and hypothesis-generating, highlighting candidate genes and epigenetic-metabolic associations for targeted validation in larger, independent cohorts using alternative analytical approaches. Show less
Adipogenesis is a complex biological process involving synchronised interplay of different nuclear receptors. Aberration in the process leads to obesity and associated disorders. Addressing the comple Show more
Adipogenesis is a complex biological process involving synchronised interplay of different nuclear receptors. Aberration in the process leads to obesity and associated disorders. Addressing the complexity of molecular mechanisms, we worked on characterising the changes in NR1C3/PPARγ-, NR1H3/LXRα- and NCoAs/SRCs-associated microRNA, genes and proteins during different time points of adipogenesis. Glucose uptake of differentiating cells was checked at selected time points with FACS. Observations on gene expression pattern pointed a correlation in adipogenic-related genes and increased expression of PPARγ, but not LXRα. Western blot experiments also supported the gene expression pattern. MicroRNAs that vary during adipogenesis was selected using bioinformatics tools and database. Real-time PCR-based experiments showed a change in the expression of mmu-mir-23a-3p, 206-3p, 17-3p, 126a-3p and 1a-3p. Mmu-mir-23a-3p showed a gradual decrease in expression corresponding to the progression of adipogenesis. MicroRNA 23a-3p and 1a-3p showed positive association to the mRNA levels of NCoA1 and 3. Overall, the study elaborates time-dependent variations in nucleic acid and protein expression during adipogenesis in accordance to fatty acid and glucose metabolism. Show less