👤 Atousa Moghadam Fard

Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) accumulation and brain atrophy; however, the assocation between plasma Aβ biomarkers and regional neurodegeneration remains unclear. We investigated whether plasma Aβ42, Aβ40, and the Aβ42/40 ratio are associated with temporal lobe atrophy measured using tensor-based morphometry (TBM) in cognitively healthy controls (HC) and participants with mild cognitive impairment (MCI). We analyzed longitudinal MRI and plasma biomarkers data from 29 participants from ADNI (HC = 14, MCI = 15) with imaging and blood samples available at baseline, 24 months, and 48 months. TBM Jacobian maps were summarized within temporal lobe regions of interest (ROIs). Associations between plasma Aβ measures and TBM-derived atrophy were examined with linear mixed-effects models, adjusting for age, sex, and APOE ε4 status, with false-discovery-rate correction. Participants with MCI showed greater temporal lobe atrophy compared with HC people, with significantly lower TBM values at follow-up. Plasma Aβ42, Aβ40, and Aβ42/40 levels showed no consistent or robust differences between diagnostic groups. After covariate adjustment and FDR correction, no plasma Aβ-TBM associations were significant at baseline or 24 months. At 48 months, positive associations were identified between Aβ42 and temporal lobe atrophy (measure 2) in HC participants (β = 0.70, p = 0.046) and between Aβ40 and measure 2 in participants with MCI (β = 0.60, p = 0.036). In contrast, a negative association was observed between the Aβ42/40 and temporal lobe atrophy (measure 2) in MCI group (β = -0.53, p = 0.049). TBM captured greater temporal lobe atrophy in participants with MCI compared with HC. Plasma amyloids showed only limited and inconsistent associations with temporal lobe atrophy over time. These findings suggest that plasma Aβ measures alone may not reliably reflect longitudinal regional neurodegeneration in early AD. Show less

Polymorphisms in the melanocortin 4 receptor (MC4R) gene with occurrence and progression of chronic diseases such as obesity and cardiovascular disease (CVD) have long been addressed but there is a lack of evidence for complex interrelationships, including direct and indirect effects of these variables. This review specifically focuses on studying the effects of healthy diet interaction and MC4R polymorphisms on the development of CVD. The quantity and quality of carbohydrates and proteins consumed are related to obesity susceptibility and cardiometabolic risk factors. A healthy dietary pattern such as a Mediterranean dietary can modulate the association between MC4R polymorphisms (rs17782313) and the risk of CVDs. Also, the Nordic diet can reduce lipid profiles such as low-density lipoprotein cholesterol (LDL-C) and total cholesterol levels. On the other hand, MC4R interaction with the dietary inflammatory index decreases high-density lipoprotein cholesterol levels and increases LDL-C and triglyceride (TG) levels. Additionally, the DASH diet decreases TG, atherogenic index of plasma, systolic blood pressure, diastolic blood pressure, and serum glucose. The interaction between MC4R genes and diets plays an important role in the development of CVD. Adherence to healthy diets such as the Mediterranean, Nordic, Anti-inflammatory, and Dash diets might be an efficient strategy to prevent CVD. The potential for personalized diets to be developed for the treatment and prevention of CVD and its related comorbidities is expected to expand as this field develops. Show less