👤 Palmi Modi

Hyaluronan and proteoglycan link protein 2 (HAPLN2) / Brain link protein-1 (Bral1) is important for the binding of chondroitin sulfate proteoglycans (CSPGs) to hyaluronan and thus for the formation of specific types of brain extracellular matrix (ECM). It is also significantly increased with aging. Moreover, machine learning has identified it as a brain-derived protein most predictive of Alzheimer's disease (AD). HAPLN2 binds to CSPGs that may sequester aggregation-prone proteins and also restrict neuronal plasticity. Because the apolipoprotein 4 (APOE4) allele increases AD risk, in the present study we have examined hippocampal lysates from APOE3 and APOE4 targeted replacement (TR) mice using unbiased proteomics, Western blot and hippocampal immunostaining. With proteomics, we observe that HAPLN2 is among the most significantly upregulated proteins in APOE4 mice. Prior work suggests HAPLN2 is particularly important to the assembly of perinodal matrix, and herein we show that it also colocalizes with Wisteria floribunda agglutinin (WFA) positive perineuronal nets (PNNs). PNNs represent a dense form of ECM that can increase GABAergic neurotransmission to alter overall excitatory/inhibitory (E/I) balance and neuronal oscillations important to mood and memory. Proteomics also detected elevated levels of high temperature requirement peptidase-1 (HTRA1), which accumulates in cerebral blood vessels harboring amyloid, in APOE4 mice. In Western blot studies, lysates from APOE4 mice also showed significantly reduced levels chondroitin-6 sulfated proteoglycans, which makes PNNs more susceptible to proteolysis and less inhibitory. In addition, immunostaining studies showed that levels of the PNN component aggrecan were increased in the hippocampus of APOE4 animals. Overall, these findings contribute to an emerging body of literature suggesting that brain extracellular matrix may be altered with aging and other risk factors for AD, and suggest that future studies should assess PNNs, peri-nodal structure and axonal conduction in the background of APOE4. Show less

Alzheimer's disease (AD) is a progressive and debilitating neurodegenerative disorder. β-site amyloid precursor protein cleaving enzyme 1 (BACE1) and glycogen synthase kinase-3β (GSK3β) contribute to Aβ plaque development, tau hyperphosphorylation, neurofibrillary tangles, and neuronal dysfunction in AD pathogenesis. This study aimed to investigate the neuroprotective potential of sabinene in an Aluminum chloride (AlCl Show less

Asparagus racemosus Willd, an Ayurvedic medicine, is known for its antioxidant, antiviral, immune-boosting, and neuro-nutraceutical benefits, particularly in female health. However, its metabolites, mechanisms of action, and target proteins are yet to be fully understood. The present study aimed to identify the metabolite constitution and metabolite-associated proteins in neuroprotective mechanisms in neurodegenerative disease. Mass spectrometry-based untargeted metabolomics and network pharmacology approaches were used to identify metabolites in A. racemosus root extract. In vitro studies, including oxidative stress regulation, neuronal apoptosis, and western blot analysis, were conducted to assess the plant's impact on Alzheimer's disease (AD). We identified 44,014 spectra in positive and negative modes, corresponding to 31,931 non-redundant metabolites at the MS1 level and 5,608 at the MS2 level, from A. racemosus root extract, which include metabolites belonging to phenols, lipids, flavonoids, isoprenoids, and fatty acyls. Novel and known compounds were identified, such as asparagine, sitosterol, arginine, muzanzagenin, pinene, flavone, and kaempferol. Network pharmacology predicted 44 potential human protein targets linked to Alzheimer's disease from these metabolites. These proteins belong to neuromodulator classes, including BACE1, CHRM3, APP, MAP2K1, GSK3B, and TNF, and some of the metabolites of A. racemosus including muzanzagenin interact with BACE1 protein. In vitro validation showed that A. racemosus regulates ROS levels, apoptosis pathways, and BACE1 expression in Alzheimer's disease (AD), highlighting its therapeutic potential. This study integrates network pharmacology and metabolomics, paving the way for clinical research into the neuropharmacological effects of A. racemosus on neurological disorders. Show less

Tinospora cordifolia has been used for thousands of years to treat various health conditions, including neurodegenerative diseases. The study aimed to elucidate the mechanism of action and protein targets of T. cordifolia in the context of Alzheimer's disease through untargeted metabolomics and network pharmacology. LC-MS/MS analysis resulted in 1186 metabolites, including known bioactive compounds such as liquiritin, Plastoquinone 3, and Shoyuflavone A, to name a few. The network pharmacology analysis highlighted the metabolite-protein interaction with the enrichment of 591 human proteins, including neurotransmitter receptors and other regulatory proteins. Pathway analysis highlighted the enrichment of cAMP, mTOR, MAPK, and PI3K-Akt signaling pathways along with cholinergic, dopaminergic, serotonergic, glutamatergic synapse, and apoptosis. The docking results suggest that T. cordifolia metabolites could interact with key Alzheimer's disease targets BACE1 and MAO-B, suggesting its role in neuroprotection. These findings provide insights into the biochemical pathways underlying T. cordifolia's therapeutic effects and provides a foundation for future exploration of T. cordifolia in the context of translational research. Show less

Background Metabolic syndrome (MetS) is a major public-health concern that substantially increases the risk of cardiovascular disease and type 2 diabetes. Traditional lipid profiles may not fully capture the atherogenic burden in MetS, prompting investigation of novel lipid biomarkers, such as lipoprotein(a) (Lp(a)), apolipoproteins, and the Comprehensive Lipid Tetrad Index (CLTI). This study evaluated the association of these biomarkers with MetS in an Indian outpatient population. Methods In a cross-sectional study of 707 adults aged 25-75 years at a tertiary care hospital in Jamnagar, Gujarat, MetS was diagnosed using NCEP-ATP III criteria. Serum Lp(a), apolipoprotein A-I (Apo A-I), apolipoprotein B (Apo B), and CLTI were measured using standard methods. Associations were tested using Chi-square analyses and logistic regression, and diagnostic performance was assessed by receiver operating characteristic (ROC) curve analysis. Results MetS was present in 397/707 (56.15%) participants, occurring in 197/332 (59.34%) of females and 200/375 (53.33%) of males. Elevated Lp(a), elevated Apo B, elevated CLTI, and reduced Apo A-I were all significantly associated with MetS (p < 0.001 for each). ROC analysis demonstrated the highest diagnostic accuracy for CLTI (area under the curve, or AUC = 0.835, 95% CI 0.806-0.862), followed by Lp(a) (AUC = 0.760, 95% CI 0.730-0.794), Apo B (AUC = 0.700, 95% CI 0.665-0.734), and Apo A-I (AUC = 0.620, 95% CI 0.584-0.657). Multivariable logistic regression identified elevated blood pressure, low high-density lipoprotein cholesterol, and elevated triglycerides as significant predictors of abnormal biomarker levels. Conclusion In this Indian outpatient cohort, CLTI and Lp(a) showed strong predictive value for MetS, and outperformed Apo A-I and Apo B when used alone. Incorporating CLTI and Lp(a) into clinical assessment may improve early detection and risk stratification in individuals at risk of MetS. Show less

BACKGROUNDHypoactive sexual desire disorder (HSDD) is characterized by a persistent deficiency of sexual fantasies and desire for sexual activity, causing marked distress and interpersonal difficulty. It is the most prevalent female sexual health problem globally, affecting approximately 10% of women, but has limited treatment options. Melanocortin 4 receptor (MC4R) agonists have emerged as a promising therapy for women with HSDD, through unknown mechanisms. Studying the pathways involved is crucial for our understanding of normal and abnormal sexual behavior.METHODSUsing psychometric, functional neuroimaging, and hormonal analyses, we conducted a randomized, double-blinded, placebo-controlled, crossover clinical study to assess the effects of MC4R agonism compared with placebo on sexual brain processing in 31 premenopausal heterosexual women with HSDD.RESULTSMC4R agonism significantly increased sexual desire for up to 24 hours after administration compared with placebo. During functional neuroimaging, MC4R agonism enhanced cerebellar and supplementary motor area activity and deactivated the secondary somatosensory cortex, specifically in response to visual erotic stimuli, compared with placebo. In addition, MC4R agonism enhanced functional connectivity between the amygdala and the insula during visual erotic stimuli compared with placebo.CONCLUSIONThese data suggest that MC4R agonism enhanced sexual brain processing by reducing self-consciousness, increasing sexual imagery, and sensitizing women with HSDD to erotic stimuli. These findings provide mechanistic insight into the action of MC4R agonism in sexual behavior and are relevant to the ongoing development of HSDD therapies and MC4R agonist development more widely.TRIAL REGISTRATIONClinicalTrials.gov NCT04179734.FUNDINGThis is an investigator-sponsored study funded by AMAG Pharmaceuticals Inc., the Medical Research Council (MRC) (MR/T006242/1), and the National Institute for Health Research (NIHR) (CS-2018-18-ST2-002 and RP-2014-05-001). Show less

A 54-year-old woman presented with presyncope and nonsustained ventricular tachycardia. Cardiac magnetic resonance imaging showed normal cardiac dimensions and left ventricular function. Late gadolinium enhancement was noted at the anterior and posterior right ventricular/left ventricular hinge points. Repeat cardiac magnetic resonance imaging at 1 year confirmed persistence of hinge point enhancement. Hypertrophic cardiomyopathy genotyping revealed the common C to T substitution at coding nucleotide 1504 of MYBPC3, c1504C>T. This variant has previously been reported as pathogenic in hypertrophic cardiomyopathy. Our case suggests that late gadolinium enhancement at the hinge points of nonhypertrophied hearts may account for clinically symptomatic ventricular arrhythmia. Show less