Glucose Flashcards
Adipokines or adipocytokines
- secreted by
- 2 types
Cytokines secreted by adipose tissue
1) Inflammatory adipokines (adiponectin): reduce inflammation and promote healing
- suppress insulin signaling resulting in insulin resistance
2) Proinflammatory adipokines (leptin):
- Leptin regulates lipid metabolism independently of food intake
- Leptin inhibits insulin where insulin stimulates leptin synthesis and secretion
- Leptin contributes to systemic inflammation and diseases associated with obesity (increase in obese ppl)
Factors can regulate the circulating leptin levels
Leptin levels higher when amount of adipose cells higher (greater amount of fat)
Glucose, insulin, estrogens and some inflammatory cytokines promote leptin secretion
Catecholamines or adrenergic agonists, thyroid hormones, androgens and inflammatory cytokines inhibit leptin secretion
Insulin
- when is it secreted
- what effect
- blood glucose
Secreted when nutrient molecules are abundant in the blood (after meal)
Exerts a hypoglycemic effect by:
- promoting uptake and storage of nutrients
- inhibiting degradation of glycogen, lipids and proteins
Released when blood glucose is high = decrease the blood glucose
Affects liver, skeletal muscle, fat tissue
Increase uptake and use of glucose (reduce blood glucose level) and amino acids
Glucagon
- when is it secreted
- what effect
- blood glucose
Secreted when blood glucose levels are low
Exerts a hyperglycemic effects by stim breakdown of glycogen
- Breakdown of triglyceride molecules and formation of glucose from noncarbohydrates sources (gluconeogenesis)
Released when blood glucose is low = increase glucose level in the blood
Affects liver cells
Increased breakdown of glycogen, and release of glucose into the blood
GLP-1 secretion upon food ingestion
Promotes satiety and reduces appetite
Increase B-cell response: enhance glucose-dependent insulin secretion
Alpha cells: decrease glucagon secretion
Liver: decreased glucagon reduces hepatic glucose output
GLP-1 degraded by DPP-4 within minutes
Hormones Effect on Glucose
Glucagon, stress hormones, E =increase glucose
Insulin, amylin (pancreatic hormone co-released w insulin), gut hormones (incretins-released by L cells of intestinal mucosa, bind to B-cells to stim insulin release) =decrease insulin
Human Growth Hormone & Blood Glucose
- insulin like growth factor (IGF)
Has diabetogenic effect (increase glucose level in blood): decrease glucose uptake and spares glucose to be available to neurons for ATP production in time of glucose scarcity
GH stim liver to secrete IGF: polypeptide hormone w high sequence similarity to insulin & has glucose-lowering effects similar to insulin and also regulate cellular DNA synthesis
IGF 1 promotes growth of body cells, protein synthesis, tissue repair, increases growth rate, cell division and hypertrophy of the muscles and bones
Diabetes Mellitus
High blood sugar
Results either from inadequate secretion of insulin (type I diabetes), or the inability of tissue to respond to insulin (type II)
Diabetes Mellitus causes…
High blood glucose level increases urine volume (polyuria), loss of water in the urine (which lead to dehydration of cells), and increase thirst
Poor use of nutrients and dehydration of cells leads to fatigue, irritability, re-current infections and prolonged wound healing
Increase damage to blood vessels and reduction of nerve function
High glucose stiffen the blood vessels
Type I
- risk factors
Combo of genes and environment:
Autoimmunity tends to run in families
- Auto-immune pancreatic beta cells destruction
- Need insulin replacement therapy
Higher rates in non-breastfed infants
Viral triggers: congenital rubella, adenovirus and mumps
Type II
- results in…
Decreased amylin B-cell secretion & satiation neurotransmission
Increased glucagon secretion, glucose production, renal glucose reabsorption
Decreased gut hormones (incretins) and glucose uptake
Increased lipolysis
Risk factors for developing type 2 diabetes
Have prediabetes
Overweight
45 years or older
Have a parent/brother/sister with type 2 diabetes
Physically active less than 3 times a week
Have ever had gestational diabetes (diabetes during pregnancy) or given birth to a baby who weighed more than 9 pounds
Are African American, Hispanic/Latino American, American Indian, or Alaska Native
If you have fatty liver disease
