Glucagon

Today is World Health Day which has been celebrated every 7th April for more than 20 years.  Each year a different theme is pushed out by the WHO is boost their profile in the media [and to provide focus on needless death and distress].  Previously covered include such problems polio, road safety, food safety [last year], motherhood.  The big global health problems get their own days, some of which have been Blobbed - Malaria + Tuberculosis - but this year's theme is diabetes [prev].

You might think that WHO should concentrate their efforts on the dispossessed of the third world. The map shows that the incidences of diabetes is far higher in the affluent West = Europe and North America, than in tropical Africa. But diabetes is everywhere and demonstrably increasing in frequency. We know that one of the triggers is a generous diet.  Recent research on [half] starved mice suggests that we will live much longer if we go to bed hungry every night.  Those of us who have tried the delights of Food Engineering will ask if it is worth living at all if we can't have bright yellow cake and ad lib pink sausages.

At The Institute, I'm just covering the endocrine system in HumPhysiol 101. The over-arching theme in how the human body ticks is the concept of homeostasis - the maintenance of balance in core body temperature, blood pressure, acid-base balance, calcium levels and everything else.  It should lead to a perpetual sense of wonder that all these things are so finely balanced that we can take them for granted . . . until they go wrong. I've talked recently about haemophilia, where that balance goes out the window. Instead of having just the right amount of factor VIII circulating that they neither haemorrhage from a bump nor suffer thrombosis, heamophiliacs get a huge blurf of Factor VIII once or twice a day which then gets degraded over the next 24 hours. It's crude and hideously expensive.

Diabetes is when the regulation of circulating blood glucose goes wrong.  Everyone knows that the level of glucose is mediated and controlled by the hormone insulin which docks onto receptors in the cell wall of pretty much all cells in the body and allows those cells to suck up enough glucose to carry out the normal metabolic activities which depend on that energy source. Without insulin, there is too much sugar in the blood which, among other bad things, encourages the growth of pathogenic bacteria. To prevent diabetes you need to produce enough insulin but you also need functional receptors. The failure of one of these supply chains causes Type-I diabetes, the other makes for Type-II diabetes. Obviously only one type is treatable by regular injections of insulin. As with Factor VIII, injecting a bucket of insulin every few hours is grossly crude compared to the elegant finely tuned dribble that healthy people maintain year-in year-out.

What's interesting, but obvious if you think about it for 3 seconds, is that there is another system in place for when blood sugar gets too low.  This is controlled by another hormone produced in the pancreas called glucagon. We need to give a bigger press to glucagon because without it we'd be equally as unhealthy as all the diabetics. Let's hear it for the Islets of Langerhans, where both hormones are produced.