👤 Maha M Hammad

Astrocytes are central regulators of neural homeostasis, synaptic function, and neuroinflammatory responses in the central nervous system (CNS). Upon pathological stimuli, astrocytes undergo reactive transformations, producing pro-inflammatory cytokines, reactive oxygen species (ROS), and chemokines, which exacerbate neuronal injury. Flavonoids, a diverse class of polyphenolic compounds found in fruits, vegetables, and medicinal plants, have emerged as potent modulators of astrocyte activity, promoting neuroprotection and cognitive enhancement. These compounds, including quercetin, hesperetin, rutin, casticin, and anthocyanins, attenuate astrocyte-mediated neuroinflammation by suppressing NF-κB, MAPK, TLR, and NLRP3 inflammasome signaling while activating antioxidant pathways such as Nrf2 and PI3K/Akt. Flavonoid-mediated modulation also enhances the synthesis and release of neurotrophic factors, including BDNF, GDNF, NGF, and TGF-β1, which support synaptic plasticity, dendritic spine formation, and network connectivity. By preserving astrocytic homeostasis, reducing gliosis, and regulating astrocyte-microglia crosstalk, flavonoids mitigate cytokine-mediated neuronal damage, restore synaptic integrity, and improve learning and memory in models of neurodegeneration, ischemia, and neuroinflammation. Preclinical evidence suggests that flavonoids can cross the blood-brain barrier, exhibit low toxicity, and synergize with other neuroprotective interventions. Understanding the molecular mechanisms of flavonoid-astrocyte interactions provides insight into precision therapeutic strategies aimed at alleviating neuroinflammation and enhancing CNS resilience, offering promising avenues for the prevention and treatment of cognitive and neurodegenerative disorders. Show less

GNAS (guanine nucleotide-binding protein, alpha stimulating) is an imprinted gene that encodes G This review examines the structure and function of GNAS and provides an overview of the disorders that are caused by defects in this gene and may feature early-onset obesity. Moreover, it elucidates the potential molecular mechanisms underlying G G Show less

Melanocortin 4 receptor (MC4R) has a well-established role in regulating appetite, food intake and energy homeostasis. Setmelanotide is an MC4R agonist currently approved for weight loss in obese adults and children with mutations in components of the leptin-melanocortin pathway. This study aims to compare structural and functional aspects of the physiological MC4R agonist α-melanocyte-stimulating hormone (α-MSH) with setmelanotide. We also aim to show the binding affinity of setmelanotide to known MC4R human missense mutations associated with obesity. AutoDock Vina was used in the structural analysis to calculate induced fit docking scores of ligand binding to MC4R wild type or the selected variants. HEK293-MC4R were utilized in the functional analysis of MC4R-actiavted pathways upon stimulating with α-MSH or setmelanotide. Our data shows that setmelanotide has a higher potency for cAMP formation and a weaker effect on ERK1/2 phosphorylation when compared to α-MSH indicating functional selectivity otherwise known as biased agonism. We also present structural data showing that setmelanotide has a higher binding affinity to MC4R compared to α-MSH. Lastly, we show that two loss-of-function and two gain-of-function MC4R variants change the conformation not only of the ligand binding pocket of the receptor but also of the peptide when bound to the receptor because the interaction network and the residues involved in the binding are altered. Taken together, our study provides important insights into the diversity of MC4R signaling pathways which will facilitate the development of personalized anti-obesity drugs via refining MC4R agonists. Show less

Hyperlipidemia represents a major risk factor for cardiovascular diseases leading to myocardial injury (MI). The present study aimed to illustrate the pattern of myocardial injury induced in diabetic hyperlipidemic rat model and the effect of vitamin D3, 10-dehydrogingerdione (10-DHGD) intake either individually or in combination form. Show less

COVID-19 is caused by Severe Acute Respiratory Syndrome Coronavirus-2, which has infected over thirty eight million individuals worldwide. Emerging evidence indicates that COVID-19 patients are at a high risk of developing coagulopathy and thrombosis, conditions that elevate levels of D-dimer. It is believed that homocysteine, an amino acid that plays a crucial role in coagulation, may also contribute to these conditions. At present, multiple genes are implicated in the development of these disorders. For example, single-nucleotide polymorphisms (SNPs) in FGG, FGA, and F5 mediate increases in D-dimer and SNPs in ABO, CBS, CPS1 and MTHFR mediate differences in homocysteine levels, and SNPs in TDAG8 associate with Heparin-induced Thrombocytopenia. In this study, we aimed to uncover the genetic basis of the above conditions by examining genome-wide associations and tissue-specific gene expression to build a molecular network. Based on gene ontology, we annotated various SNPs with five ancestral terms: pulmonary embolism, venous thromboembolism, vascular diseases, cerebrovascular disorders, and stroke. The gene-gene interaction network revealed three clusters that each contained hallmark genes for D-dimer/fibrinogen levels, homocysteine levels, and arterial/venous thromboembolism with F2 and F5 acting as connecting nodes. We propose that genotyping COVID-19 patients for SNPs examined in this study will help identify those at greatest risk of complications linked to thrombosis. Show less