Metabolic Syndrome Flashcards
Risk factors involved in metabolic syndrome (5)
Raised BP Raised TAG Raised fasting glucose Lowered HDL central obesity
Which two features appear to be essential for metabolic syndrome
Central adiposity
Insulin resistance
Explain how hyperlioplytic state of central adipose tissue may affect metabolism (5)
May lead to FFA draining into hepatic portal vein
FA may be stored in liver at high concentrations
May lead to:
Hyperinsulinemia
Increased hepatic glucose production
Hypertriglyeridemia
Abdominal adiposity and endocrines (6)
Adipose tissue is an endocrine organ
Secretes more inflammatory cytokines during obese state
Cytokines may contribute to:
Insulin resistance
Thrombotic state
Hypertensive state
Overproduction of TNF-a may also cause b-cell death in pancreatic islets
Abdominal obesity as a biomarker (2)
Excess central adipose tissue may be a marker of the inability of subcutaneous fat to act as protective metabolic sink
Individuals who cannot store surplus fat in subcutaneous tissue may accumulate fat at undesired sites
Accumulation of fat at which organs are hypothesised to be critical for T2D?(2)
Liver
Pancreas
Lim 2011 fat loss study (3)
Demonstrated normalisation of beta cell function and hepatic insulin sensitivity in T2D
Using calorie restriction
Associated with decreased pancreatic and liver TAG stores
Insulin resistance and VLDLs (5)
Impaired insulin signalling increases lipolysis Results in increased FFAs FFAs taken up by liver Greater amount of VLDLs produced Also impairs VLDL clearance
VLDLs and atherogenesis (6)
VLDLs are metabolised to small dense LDLs
Which promote atheroma formation
TGs in VLDL are transferred to HDL
Results in TG rich HDL which are rapidly cleared for circulation
Leaves fewer HDL for reverse cholesterol transport from the vasculature
This further promotes atherosclerosis
Define metabolic syndrome
Cluster of risk factors for CVD and T2D
Metabolic syndrome essay plan (11)
Definition Risk factors Essential features Metabolic abnormalities mechanisms Lipolysis portal vein B cell function Endocrines Biomarker IR and VLDL production VLDL atherogenesis NAFLD
What is NAFLD (2)
Fatty inflammation of the liver
That is not due to excessive alcohol use
Which metabolic disorders is NAFLD associated with?(3)
CVD
T2D
Metabolic syndrome
What is NAFLD characterised by?(2)
Hepatic steatosis -accumulation of TAG in liver
Steatohepatitis -inflammation and fibrosis
First step of NAFLD (4)
Hyperinsulinaemia caused by insulin resistance
Increase fat synthesis in liver
Decreased VLDL secretion
Increase in FFA from AT due to AT lipolysis
Effects of high glucose and FFAs on b-cells (2)
High glucose is very toxic to b-cells
Glucose and FFAs enter b-cells and induce inflammation
NAFLD multi hit (3)
After steatosis the liver becomes vulnerable to:
Mitochondrial dysfunction
Oxidative damage
And many other factors
