👤 Mythily Subramaniam

Hypertensive disorders of pregnancy (HDP) are associated with future cardiovascular disease but mechanisms are not well defined. We examined the association between HDP and atherosclerotic cardiovascular disease (ASCVD) biomarkers 5-10 years after childbirth. Secondary analysis of the NICHD MFMU Network Gestational Diabetes (GDM) Trial Follow-Up study. Participants were recruited and biospecimens obtained 5-10 years after the original trial of treatment for mild GDM. Patients were included if a biospecimen was available and their HDP status was known. We compared patients who experienced HDP to normotensive controls. Outcomes included unadjusted medians and mean concentrations of ASCVD serum biomarkers Apolipoprotein B (ApoB), high-sensitivity C-reactive protein (hs-CRP), and creatinine. Generalized linear models were used to compare concentrations between groups. Of 740 participants in this analysis, 78 had been diagnosed with HDP. Mean duration of follow up after delivery was 7.1 ± 1.3 years for both groups. Unadjusted means of each biomarker were not different between groups. After adjusting for obesity, mean serum creatinine was elevated in women who had been diagnosed with HDP (0.77 mg/dL 95%CI (0.72, 0.82)) compared to controls (0.71 mg/dL 95%CI (0.69, 0.72)), p = 0.02. Adjusted means for ApoB between women with HDP and controls were 64.2 mg/dL (95%CI (59.3, 69.5)) and 60.6 mg/dL (95%CI (58.9, 62.3)), (p = 0.18), and for hs-CRP mg/L were 14.6 (95%CI (11.4, 19.1)) and 14.5 mg/L (95%CI (13.3, 15.9)), (p = 0.91). In patients with HDP compared to normotensive controls, serum creatinine, but not ApoB or hs-CRP, was modestly elevated within 10 years of childbirth. Show less

Externalized histones erupt from the nucleus as extracellular traps, are associated with several acute and chronic lung disorders, but their implications in the molecular pathogenesis of interstitial lung disease are incompletely defined. To investigate the role and molecular mechanisms of externalized histones within the immunologic networks of pulmonary fibrosis, we studied externalized histones in human and animal bronchoalveolar lavage (BAL) samples of lung fibrosis. Neutralizing anti-histone antibodies were administered in bleomycin-induced fibrosis of C57BL/6 J mice, and subsequent studies used conditional/constitutive knockout mouse strains for TGFβ and IL-27 signaling along with isolated platelets and cultured macrophages. We found that externalized histones (citH3) were significantly ( Show less

Chylomicronemia has either a monogenic or multifactorial origin. Multifactorial chylomicronemia is the more common form and is due to the interaction of genetic predisposition and secondary factors such as obesity, diabetes, unhealthy diet, and medications. We report a case of a 38-year-old man who was diagnosed with multifactorial chylomicronemia following presentation with a subarachnoid hemorrhage requiring emergency surgery through a burr hole; lactescent cerebrospinal fluid mixed with blood was observed through the burr hole. The serum triglyceride concentration was 52⋅4 mmol/L with a detectable triglyceride concentration in the cerebrospinal fluid. Rapid weight gain leading to obesity and related unfavorable lifestyle factors were identified as key secondary causes of chylomicronemia. Gene testing revealed a homozygous variant in Show less

Genome-wide association studies (GWAS) on Parkinson's disease (PD) have mostly been done in Europeans and Japanese. No study has been done in Han Chinese, which make up nearly a fifth of the world population. We conducted the first Han Chinese GWAS analysing a total of 22,729 subjects (5,125 PD cases and 17,604 controls) from Singapore, Hong Kong, Malaysia, Korea, mainland China and Taiwan. We performed imputation, merging and logistic regression analyses of 2,402,394 SNPs passing quality control filters in 779 PD cases, 13,227 controls, adjusted for the first three principal components. 90 SNPs with association P < 10-4 were validated in 9 additional sample collections and the results were combined using fixed-effects inverse-variance meta-analysis. We observed strong associations reaching genome-wide significance at SNCA, LRRK2 and MCCC1, confirming their important roles in both European and Asian PD. We also identified significant (P < 0.05) associations at 5 loci (DLG2, SIPA1L2, STK39, VPS13C and RIT2), and observed the same direction of associations at 9 other loci including BST1 and PARK16. Allelic heterogeneity was observed at LRRK2 while European risk SNPs at 6 other loci including MAPT and GBA-SYT11 were non-polymorphic or very rare in our cohort. Overall, we replicate associations at SNCA, LRRK2, MCCC1 and 14 other European PD loci but did not identify Asian-specific loci with large effects (OR > 1.45) on PD risk. Our results also demonstrate some differences in the genetic contribution to PD between Europeans and Asians. Further pan-ethnic meta-analysis with European GWAS cohorts may unravel new PD loci. Show less

The striatum of the brain coordinates motor function. Dopamine-related drugs may be therapeutic to patients with striatal neurodegeneration, such as Huntington's disease (HD) and Parkinson's disease (PD), but these drugs have unwanted side effects. In addition to stimulating the release of norepinephrine, amphetamines, which are used for narcolepsy and attention-deficit/hyperactivity disorder (ADHD), trigger dopamine release in the striatum. The guanosine triphosphatase Ras homolog enriched in the striatum (Rhes) inhibits dopaminergic signaling in the striatum, is implicated in HD and L-dopa-induced dyskinesia, and has a role in striatal motor control. We found that the guanine nucleotide exchange factor RasGRP1 inhibited Rhes-mediated control of striatal motor activity in mice. RasGRP1 stabilized Rhes, increasing its synaptic accumulation in the striatum. Whereas partially Rhes-deficient (Rhes Show less