Faculty of Health, Engineering and Science
School of Medical Sciences/Centre of Excellence for Alzheimer's Disease Research and Care
The global epidemic in obesity and diabetes has affected individuals in both the developing and developed world with the global death rate (63%) related to chronic diseases with 35% attributed to cardiovascular disease and stroke, 21 % to cancer and 12 % to chronic respiratory disease. The interest in connections between the global stroke epidemic, dementia and Alzheimer’s disease (AD) has increased with hypertension, smoking, diabetes, obesity, poor diet, physical inactivity, atrial fibrillation, excessive alcohol consumption, abnormal lipid profile and psychosocial stress/depression implicated in their pathogenesis. The connection between stroke and AD is possibly related to the low adiponectin and high density lipoprotein (HDL) cholesterol levels that are found in hypertensive, obese, diabetic and AD individuals. In obesity adipocyte dysfunction may be related to the down regulation of the AD gene Sirtuin 1, overexpression of the amyloid precursor protein (APP) and mitochondrial apoptosis with relevance to the renin-angiotensin system (RAS) that is associated with accelerated aging, NAFLD, stroke and AD. The unresolved finding of low plasma HDL and adiponectin in the metabolic syndrome may involve the stress hormone angiotensin II (Ang II) with vascular disturbances. Increased levels of adipocyte Ang II are possibly linked to the low plasma HDL contents in stroke and AD individuals. In obese and diabetic individuals the release of stress factors and diet control the activation of the RAS with increased levels of Ang II that are possibly implicated in the dyslipidemia associated with hypertension, cardiovascular disease, stroke and AD related dementia.