Lecture 06

Cards (63)

  • What gene codes for leptin?
    OB gene
  • What is the effect of mutations in the OB gene?
    They result in uncontrolled overeating
  • What does the DB gene code for?
    Leptin receptor
  • What does the db/db genotype indicate?
    Genetically diabetic, dyslipidemic, obese
  • What does the Fa gene represent?
    Normal leptin receptor
  • What are Tyr to Phe variants associated with?
    Leptin receptor mutations
  • How many amino acids are altered in some obesity-related mutations?
    Three amino acids
  • What is the effect of increased receptor sensitivity to leptin?
    It may reduce overeating
  • What is the LETO strain of rat known for?
    Being genetically obese
  • What does OLETF stand for?
    Otsuka-Long-Evans-Tokashima-Fatty rats
  • What is the difference in fatty disposition between LETO and OLETF rats?
    OLETF has a higher fat disposition
  • What is the significance of the CCK-A receptor?
    It is involved in obesity
  • What happens to the CCK-A receptor in OLETF rats?
    CCK-A receptor is deleted
  • What is leptin's role in the body?
    Controls eating behaviour
  • How does the fa/fa genotype affect individuals on a high-fat diet?
    They gain weight significantly
  • What is the role of brown adipose tissue (BAT) in obesity?
    It is not activated in obese individuals
  • What does CCK stand for?
    Cholecystokinin
  • What are the types of CCK receptors?
    CCK-A, CCK-B, CCK-X-R
  • What is the relationship between CCK-A receptor polymorphisms and Parkinson’s disease?
    They are associated with the disease
  • What is the effect of Vitamin E on cholesterol synthesis?
    It down-regulates enzyme expression
  • What is the role of carnitine in the body?
    Import of fatty acids into mitochondria
  • What are the main sources of carnitine?
    Red meat
  • What is the effect of high doses of carnitine in athletes?
    Improves performance
  • What is the consequence of excess Vitamin A?
    It is highly toxic
  • What is phytanic acid derived from?
    Phytol
  • What effect does high phytanic acid have on UCP-1 mRNA levels?
    It increases levels in BAT
  • Where is UCP-2 expressed at high levels?
    In pancreatic islet cells
  • What does UCP-2 regulate?
    Cytoplasmic ATP/ADP ratio
  • How does UCP-3 affect glucose uptake?
    Increases glucose transport into cells
  • What is the effect of UCP-3 overexpression in mice?
    Prevents weight gain on high-fat diet
  • What is the role of UCP-4 in the body?
    Improves insulin sensitivity
  • What is the impact of obesogenic compounds on obesity levels?
    They contribute to increased obesity
  • What is phthalic acid used for?
    Improves plasticity of food wrappings
  • What is the effect of bisphenol A?
    It acts as a pseudo-oestrogen
  • How does atrazine affect hormone secretion?
    Decreases luteinising hormone secretion
  • What is the role of organo-bromines?
    They are endocrine disruptive agents
  • What is the effect of organo-tins on mitochondria?
    They inhibit FoF1 in mitochondria
  • What is the relationship between calorie intake and obesity levels?
    Calorie intake has remained constant
  • What is the primary reason for increased obesity despite constant calorie intake?
    Lifestyle changes
  • How do endocrine disruptors affect testosterone?
    They block testosterone binding