diabetes

• Diabetes mellitus

  condition in which the body is no longer able to produce sufficient insulin to control its blood glucose concentration leading to a prolonged hyperglycaemia after a meal rich in sugars + other carbohydrates

  
• Type 1 diabetes

  insulin-dependent diabetes or as juvenile-onset diabetes as it usually starts in childhood

  • thought to be the result of autoimmune response

  → a person with Type 1 can no longer synthesise sufficient insulin + cannot store excess glucose as glycogen

  • excess glucose in blood is not removed quickly, leaving a prolonged period of high concentration

  →however when the blood glucose falls, there is no store of glycogen that can be used to release

  • therefore, the blood glucose concentration falls too low which is when a diabetic can suffer a ‘hypo’ - a period of hypoglycaemia
• Type 2 diabetes

  insulin-independent diabetes

  • can produce insulin but not enough
  • age is a factor as their responsiveness to insulin declines due to probably the specific receptors on the surface of the liver + muscle cells become less responsive + cells lose their ability to respond to the insulin in blood

  → type 2 is almost permanently raised, which can damage the major organs + circulation

  certain factors that bring an earlier onset of type 2:

  • obesity - lack of regular exercise - a diet high in sugars, particularly refined sugars - being of Asian or Afro-Caribbean origin - family history
• Treating diabetes

  the effects of diabetes are severe + become worse with time

  • it is therefore important that diabetes is diagnosed as early as possible so that treatment can be started
• Treating Type 1

  usually treated using insulin injections

  alternative to insulin injection:

  • insulin pump therapy - a small device constantly pumps insulin (at a controlled rate) into the bloodstream through a needle that is permanently inserted under the skin
  • islet cell transplantation - healthy beta cells from the pancreas of a deceased donor are implanted into pancreas of someone with Type 1 diabetes
  • a complete pancreas transplant
• Treating type 1 (contiunation)

  • recent research shows that it is possible to treat type 1 diabetes using stem cells to grown new islets of Langerhans in pancreas

  → commonly found in bone marrow and placenta however scientist have found precursor cells in the pancreas of adult mice which are capable of developing into a variety of cell types + may be true stem cells

  → if similar cells can be found in human pancreas then they could be used to produce beta cells in patients with Type 1, giving freedom from daily insulin injections
• Treating type 2

  treated by changing lifestyle

  • a type 2 diabetic will be advise to lose weight, exercise regularly + carefully monitor their diet

  → may be supplemented by medication that reduces the amount of glucose in liver to release to the bloodstream or that boosts the amount of insulin released from pancreas

  severe cases may include insulin injections or use of other drugs that slow down absorption of glucose from digestive system
• The source of insulin for treating diabetes

  
  

  insulin used to be extracted from pancreas of animals (usually pigs as they closely match) but more recently insulin has been produced by Escherichia coli Bacteria that have undergone genetic modification to manufacture human insulin
• The source of insulin for treating diabetes

  advantages of GM (genetic modification) :

  • exact copy of insulin therefore faster + effective
  • less chance of developing tolerance to insulin
  • less chance of rejection due to immune response
  • lower risk of infection
  • cheaper to manufacture insulin than to extract it from animals
  • manufacturing process is more adaptable to demand
  • some people are less likely to have moral objections to using insulin produced from bacteria than to using that extraction from animals