A Power Program for Student Review
A Review of Teaching Highlights from Last Month
The 6-Month Program
- Biophysics Of Obesity
- Obesity...The Metabolic Syndrome
- Obesity...Insulin Resistance...Diabetes
- Diabetes Complications: Glycoproteinopathies
- Obesity...Feeling Sick and Liverish
Last month’s Twitter Teaching Focus: Diabetes Complications…is reviewed for your update in this Countdown….
For decades after the discovery of insulin, doctors regarded the complications of diabetes (eyes, nerves, kidneys and arteries), usually encountered after years of treatment, as intrinsic to the disease itself. However, many careful studies over decades show that persistently elevated levels of blood glucose do the damage. So the modern emphasis in diabetes care is on the best possible blood sugar control.
Blood glucose forms distorting sugar-protein complexes (glycoproteins) by reacting with selected tissues, and they slowly degrade the tissue’s ability to function. Cellular organization is distorted and tissue/organ performance gradually destroyed.
In the eye, glycoprotein complexes of the retinal capillaries lead to ‘dot and blot’ bleeding…and cloud-like puffs of serum exudate. They can come and go in severity, often interfering with vision. In the US today, diabetes has become the most common cause of new cases of legal blindness.
In the kidney, microscopic filtration systems (called renal glomeruli) are progressively damaged. Plasma proteins leak from filtered blood into the urine. As the kidneys gradually sicken and fail, their contribution to a healthy body declines. The blood pressure goes up, and red blood cell production falls. Hypertension and anemia develop…all complicating factors in diabetic kidney failure.
When the long nerves of the limbs are affected by diabetic neuropathy (especially in the legs) they often begin with numbness and tingling. The skin’s ability to recognize much sensation is reduced or lost. The toes become vulnerable to unrecognized (and characteristically painless) damage during the day. Diabetics should examine their feet closely at bedtime each and every evening, and give immediate attention to any injury or break in the skin.
Damaging sugar-protein complexes also occur in the intima…that delicate lining of all arteries. By distorting the intima’s integrity, sugar-protein complexes allow more cholesterol to collect underneath, more atheroma to build. This is another reason diabetics are prone to earlier heart attacks and strokes, to developing dead toes, and losing their feet.
An unprotected and damaged toe lives in a dense environment of bacteria, ever ready to invade random breaks in the skin. Trouble is often first noticed when a sock sticks momentarily during removal at bedtime. An ulcer forms, and the toe darkens. The foot’s defenses against infection are also handicapped by a poor circulation. In the US today, diabetes is the underlying cause for most surgical amputations of a foot. Sadly, a surviving foot is also vulnerable, and usually lost within a few years of the first.
Glycoprotein complexes also form with the hemoglobin of circulating red blood cells, and doctors have turned this sugar-protein ‘complication’ to clinical advantage…as an indicator of the quality of sugar control in patients as they go about living their daily lives. Called Hemoglobin A1c, its levels in a diabetic’s blood should ideally be well-under 6%.
Most of the body’s muscle mass and arterial circulation are located below the waist,…in the legs. Daily walks can increase their blood-carrying capacity, and over time help provide a cushion against the risk of damaged toes and feet. Take daily walks. Never remain seated beyond an hour anywhere without getting up and moving around.
To help keep the blood sugar down at mealtimes, not all carbohydrates are created equal. The complex ones, like vegetables and whole grains are best. They take more time to digest and dismantle, so their effect on a rising blood sugar after meals is slower and lower. Beyond oatmeal, ever think of a vegetable (like a sweet potato or bean stew) for breakfast?BLAST OFF