Biology subjects

Agarwal, S. M.

Publications and source records attributed to Agarwal, S. M..

3 recordsLinked to original sources

bioRxiv2025

The fecal microbiota transplantation from drug-naive schizophrenia patients distinctively changes gut microbiome and metabolic profiles in male and female mice

BackgroundEmerging evidence suggests a role for the gut microbiome in schizophrenia (SCZ) and antipsychotic-induced metabolic perturbations. Using human fecal microbiota transplantation (FMT) in mice, this study investigated the role of gut microbiome in metabolic changes related to SCZ and antipsychotic (olanzapine) treatment. Methods5-6 weeks old germ-free NIH Swiss mice of both sexes received microbiota from either SCZ patients (SCZ-FMT) or healthy controls (HC-FMT) followed by a diet with or without olanzapine for six-weeks. Food intake and body weight were monitored weekly, and an intraperitoneal glucose tolerance test and open field test were performed. Serum glucose, and insulin were measured. Gut microbiome characterization and short-chain fatty acids (SCFAs) quantification were performed in the cecal samples using 16S rRNA gene sequencing and gas chromatography-mass spectrometry, respectively. ResultsOlanzapine treatment decreased the locomotor activity in the open field test, irrespective of sex or microbiota. Female SCZ-FMT recipient mice exhibited insulin resistance compared to HC-FMT, irrespective of olanzapine treatment. Female SCZ-FMT mice showed significantly lower alpha-diversity compared to HC-FMT, whereas olanzapine treatment increased alpha-diversity. SCZ-FMT and olanzapine treatment differentially altered the microbial abundances, and metabolic pathways in male and female mice. Interestingly, cecal SCFAs, mainly acetate levels, were significantly decreased in female SCZ-FMT mice compared to HC-FMT, while olanzapine treatment increased acetate levels in male mice. Both male and female SCZ-FMT mice showed elevated levels of isovaleric acid compared to HC-FMT. ConclusionThese preliminary findings suggest that gut microbiome could be a predisposing factor contributing to the intrinsic risk of developing type 2 diabetes associated with SCZ in females. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/675957v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@8cfd10org.highwire.dtl.DTLVardef@3a6031org.highwire.dtl.DTLVardef@813428org.highwire.dtl.DTLVardef@87609e_HPS_FORMAT_FIGEXP M_FIG Graphical abstract C_FIG

neuroscience↗

bioRxiv2025

Protective effects of central leptin on whole-body energy homeostasis upon acute olanzapine exposure

Second-generation antipsychotic use is associated with severe metabolic side effects such as obesity and type 2 diabetes. Leptin is a hormone that is secreted by adipose tissue, and it acts on the brain to decrease body weight by reducing food intake and stimulating energy expenditure. Leptin also improves glucose and lipid metabolism. We examined the short-term impact of olanzapine, a commonly used second-generation antipsychotic, on the central leptin-mediated regulation of energy balance, lipid metabolism, and hypothalamic kinase activity. Male Sprague Dawley rats were given an acute intracerebroventricular (ICV, 3rd ventricle) injection of either leptin or vehicle, combined with subcutaneous olanzapine or vehicle. As expected, ICV leptin decreased food intake and importantly, olanzapine did not block this effect. Administration of leptin, olanzapine, or their combination reduced the average respiratory exchange ratio (RER) during the light cycle, which indicates that fat oxidation was increased. In the dark cycle, leptin decreased the average RER regardless of olanzapine administration, and in the presence of leptin, olanzapine did not affect the average RER. Leptin did not alter the olanzapine-induced increase in serum triglyceride concentrations. Olanzapine and central leptin treatment differentially activated hypothalamic kinases. In conclusion, regulation of food intake and fuel preference by central leptin is intact following acute olanzapine administration.

neuroscience↗

bioRxiv2019

White Matter Microstructure and its Relation to Clinical Features of Obsessive-Compulsive Disorder: Findings from the ENIGMA OCD Working Group

ImportanceMicrostructural alterations in cortico-subcortical connections are thought to be present in Obsessive-Compulsive Disorder (OCD). However, prior studies have yielded inconsistent findings, perhaps because small sample sizes provided insufficient power to detect subtle abnormalities. ObjectiveTo investigate microstructural white matter alterations and their relation to clinical features in the largest dataset of adult and pediatric OCD to date. Design, Setting, and ParticipantsIn this cross-sectional case-control magnetic resonance study, we investigated diffusion tensor imaging metrics from 700 adult patients and 645 adult controls, as well as 174 pediatric patients and 144 pediatric controls across 19 sites participating in the ENIGMA-OCD Working Group. Main Outcomes and MeasuresWe extracted measures of fractional anisotropy (FA) as main outcome, and mean diffusivity, radial diffusivity, and axial diffusivity as secondary outcomes for 25 white matter regions. We meta-analyzed patient-control group differences (Cohens d) across sites, after adjusting for age and sex, and investigated associations with clinical characteristics. ResultsAdult OCD patients showed significant FA reduction in the sagittal stratum (d=-0.21, z=-3.21, p=0.001) and posterior thalamic radiation (d=-0.26, z=-4.57, p<0.0001). In the sagittal stratum only, lower FA was associated with a younger age of onset (z=2.71, p=0.006), longer duration of illness (z=-2.086, p=0.036) and a higher percentage of medicated patients in the cohorts studied (z=-1.98, p=0.047). No significant association with symptom severity was found. Pediatric OCD patients did not show any detectable microstructural abnormalities compared to matched controls. Conclusions and RelevanceMicrostructural alterations in projection and association fibers to posterior brain regions were found in adult OCD, and related to disease course and medication status. Such results are relevant to models positing deficits in connectivity as a crucial mechanism in OCD. KEY POINTSO_ST_ABSQuestionC_ST_ABSDo patients with Obsessive-Compulsive Disorder (OCD) show white matter microstructural alterations, and are these alterations related to clinical features? FindingsData from 19 sites of the ENIGMA-OCD Consortium were included, involving 700 adult patients and 645 adult controls, 174 pediatric patients and 144 pediatric controls. Diffusion tensor imaging data were meta-analyzed using a harmonized data processing and analysis protocol. Adult, but not pediatric, patients showed alterations in the sagittal stratum and posterior thalamic radiation; sagittal stratum differences were associated with clinical features. MeaningMicrostructural abnormalities found in adult but not in the pediatric cohort, are related to illness duration and medication status.

neuroscience↗