👤 Madiha Ishaq

Alzheimer's disease (AD) pathology disrupts functional brain connectivity long before symptoms emerge. African Americans face elevated AD risk, yet underlying mechanisms remain unclear. Genetic risk differs by ancestry: APOE-ε4 strongly predicts late-onset AD in European ancestry, whereas ABCA7 rs115550680 confers substantial risk in African ancestry. Yet, how these variants influence neural function in African Americans is unclear. The medial temporal lobe (MTL) is an early target of AD pathology and resting-state functional Magnetic Resonance Imaging (rs-fMRI) measures of dynamic network connectivity (hereafter "flexibility"), the brain's capacity to dynamically reconfigure connectivity, provide a sensitive metric of network adaptability, potentially preceding structural decline. However, comparative influence of APOE-ε4 and ABCA7 rs115550680 on MTL flexibility and subregional volumes in this population is unknown. 146 older African Americans (Mean Show less

Traumatic brain injury (TBI) causes cortical dysfunction by increasing oxidative stress, neuroinflammation, apoptosis, and mitochondrial dysregulation, and impairing neurotrophic signaling and neurogenesis. This systematic review aimed to evaluate the effectiveness of exercise training on cortical molecular dysregulation and motor function in post-TBI. Following PRISMA 2020 guidelines, PubMed, EMBASE, and Web of Science were searched up to August 2025. Of 1173 records, 35 studies involving exercise training in post-TBI animal models were included. Exercise training protocols included voluntary wheel running, treadmill running, and swimming, with durations ranging from 7 to 63 days. Study quality was assessed using the CAMARADES checklist. Exercise training increased cortical glutathione and Na Show less

A major goal of biomedicine is to understand the function of every gene in the human genome. Loss-of-function mutations can disrupt both copies of a given gene in humans and phenotypic analysis of such 'human knockouts' can provide insight into gene function. Consanguineous unions are more likely to result in offspring carrying homozygous loss-of-function mutations. In Pakistan, consanguinity rates are notably high. Here we sequence the protein-coding regions of 10,503 adult participants in the Pakistan Risk of Myocardial Infarction Study (PROMIS), designed to understand the determinants of cardiometabolic diseases in individuals from South Asia. We identified individuals carrying homozygous predicted loss-of-function (pLoF) mutations, and performed phenotypic analysis involving more than 200 biochemical and disease traits. We enumerated 49,138 rare (<1% minor allele frequency) pLoF mutations. These pLoF mutations are estimated to knock out 1,317 genes, each in at least one participant. Homozygosity for pLoF mutations at PLA2G7 was associated with absent enzymatic activity of soluble lipoprotein-associated phospholipase A2; at CYP2F1, with higher plasma interleukin-8 concentrations; at TREH, with lower concentrations of apoB-containing lipoprotein subfractions; at either A3GALT2 or NRG4, with markedly reduced plasma insulin C-peptide concentrations; and at SLC9A3R1, with mediators of calcium and phosphate signalling. Heterozygous deficiency of APOC3 has been shown to protect against coronary heart disease; we identified APOC3 homozygous pLoF carriers in our cohort. We recruited these human knockouts and challenged them with an oral fat load. Compared with family members lacking the mutation, individuals with APOC3 knocked out displayed marked blunting of the usual post-prandial rise in plasma triglycerides. Overall, these observations provide a roadmap for a 'human knockout project', a systematic effort to understand the phenotypic consequences of complete disruption of genes in humans. Show less

Evidence is sparse about the genetic determinants of major lipids in Pakistanis. Variants (n=45 000) across 2000 genes were assessed in 3200 Pakistanis and compared with 2450 Germans using the same gene array and similar lipid assays. We also did a meta-analysis of selected lipid-related variants in Europeans. Pakistani genetic architecture was distinct from that of several ethnic groups represented in international reference samples. Forty-one variants at 14 loci were significantly associated with levels of HDL-C, triglyceride, or LDL-C. The most significant lipid-related variants identified among Pakistanis corresponded to genes previously shown to be relevant to Europeans, such as CETP associated with HDL-C levels (rs711752; P<10(-13)), APOA5/ZNF259 (rs651821; P<10(-13)) and GCKR (rs1260326; P<10(-13)) with triglyceride levels; and CELSR2 variants with LDL-C levels (rs646776; P<10(-9)). For Pakistanis, these 41 variants explained 6.2%, 7.1%, and 0.9% of the variation in HDL-C, triglyceride, and LDL-C, respectively. Compared with Europeans, the allele frequency of rs662799 in APOA5 among Pakistanis was higher and its impact on triglyceride concentration was greater (P-value for difference <10(-4)). Several lipid-related genetic variants are common to Pakistanis and Europeans, though they explain only a modest proportion of population variation in lipid concentration. Allelic frequencies and effect sizes of lipid-related variants can differ between Pakistanis and Europeans. Show less