Type-2 Diabetes and the role of incretins

The incretins are the hormones, which are released into the blood circulation in response to nutrients we eat. These peptide hormones are generally released within minutes of eating or enteral nutrition. In humans, the major incretins are: (i) Glucagon like peptide-1 (GLP-1) and (ii) Glucose-dependent insulinotropic polypeptide (GIP). GLP-1 is secreted by L-cells in the ileum and colon, while GIP is secreted by K-cells in the duodenum of our alimentary canal. GLP-1 and GIP stimulate insulin secretion by the pancreas and also affect the gut and the brain. Their combine effect make significant contribution in glucose homoeostasis, particularly in scaling down the peak of postprandial glucose level. It has been proved through experimental studies that the GLP-1 has the major incretin effect; that is around 80% of the combine effect of GLP-1 and GIP. These incretins probably act via glycoprotein-coupled receptors.

Non-insulin dependent diabetes mellitus (NIDDM) or type-2 diabetes mellitus (Type-2 DM) is characterized by pancreatic beta-cell dysfunction and variable degree of insulin response. Complex interaction of genetics and environmental factors are responsible for metabolic disorders leading to diabetes. Taming of hyperglycemia through medicines, dietary control and regular exercise is possible. Increasing prevalence of obesity and reduced physical activity is directly related to the increasing prevalence of type-2 DM, worldwide. Oral antidiabetic agents, diet and or exercise and insulin are currently used for the treatment of patients with diabetes. Existing antihyperglycemic agents are often associated with an increased risk of adverse effects (such as weight gain and hypoglycemia) and most often become less effective due to histological/cellular variations (progressive beta cell failure) in the pancreas of the patient.

Incretins provide insulinotropic stimulus and thus lower the blood glucose level by increasing insulin secretion. However, the incretin response to a meal lasts approximately around 3 hours as the incretin molecules have very short half-life (<5 minutes) and are metabolized quickly. An enzyme known as dipeptidyl peptidase-4 (DPP4), produced by endothelial cells, disintegrate the incretin molecules within 2-3 minutes of their secretion. Poor incretin response has been observed in patients with type-2 diabetes during the glucose tolerance test as indicated by reduced level of GLP-1 as compared to normal individuals. The functional response (insulinotropic response) of GLP-1 was found to be intact in patients with type-2 diabetes and that gave new direction to the treatment regimen of diabetes. At present the incretin system has been under active study to find out the effective compounds for the treatment of type-2 diabetes. Pharmaceutical compounds like: (1) GLP-1 'analogues' or GLP-1 receptor agonists which are resistant to breakdown by DPP4 and (2) Incretin enhancers which inhibit the action of DPP4 on GLP-1 molecules, have been under active study for use in new formulations.

Exenatide is already in clinical use after its approval by US-FDA. Exenatide is a biosynthetic form of GLP-1 analogue-exendin-4. Exendin-4 is a naturally occurring GLP-1 found in the saliva of a lizard known as Gila monster. It was approved by US-FDA in 2005 for use in combination with metformin or sulfonylureas or both together. Exenatide is administered twice daily before meals by subcutaneous injections from a pre-filled pen. Incretin enhancers improve the control of glucose level in blood by inhibiting DPP4 action on incretin hormones especially GLP-1 molecules. Incretin enhancer Sitagliptin was approved by US-FDA in 2006 and Vildagliptin was approved by US-FDA in 2007, and both have been used as monotherapy or in combination with antidiabetic drugs like metformin or thiazolidinedione for glycemic control in patients affected by type-2 diabetes.

Important Note: Antihyperglycemic treatment should always be taken in consultation with a physician or specialized diabetologist.

Happy New Year

May God Decorate Every Golden Ray of the Sun Reaching You With Health, Wealth, Success and Prosperity for You in the Year "2010".

Wish you a "Very Happy and Memorable New Year".

Tips to fight Malabsorption Syndrome

Normally our body has the ability to digest the food we eat and absorb the nutrients form it. Over 9 meters long alimentary canal helps to accomplish the function of digestion and absorption. Malabsorption syndrome could be defined as the inability of our body to absorb essential nutrients from the food. Malabsorption syndrome can affect any person irrespective of age and gender. It may lead to a variety of deficiencies like that of vitamins, minerals, proteins, fatty acids and other nutrients. The associated cause may be digestive or dietary deficiency. The factors that contribute to cause the malabsorption syndrome may be adoption of dieting schedules for reducing weight, habitual & excessive intake of alcohol, food allergies, a diet deficient in B-vitamins and diseases of the digestive organs like pancreas and liver. Intestinal malfunction caused due to excessive use of antibiotics and/or laxatives can also lead to malabsorption syndrome.

Symptoms of Malabsorption Syndrome:

1. Fatigue and weight loss. However, some obese persons may also have malabsorption syndrome.
2. Recurrent diarrhoea and constipation.
3. Persistent abdominal discomfort with gas and bloating.
4. Unpredictable appetite.
5. Treatment of above cited conditions with a variety of medicine further complicate the problem.

Some complications of Malabsorption Syndrome:

1. Anemia and thinning & falling of hair.
2. Muscular cramps.
3. Psychological & behavioral changes.
4. Menstrual problems in female patients.

Tips to fight Malabsorption Syndrome:

1. Adopt dietary discipline in terms of quality, quantity and timings of intake.
2. Avoid fried and starchy foods.
3. Avoid excessive intake of alcohol.
4. Avoid too cold or too hot and preserved foodstuffs.
5. Avoid over medication with antibiotics.
6. Take spicy curd or buttermilk as it supports the intestinal flora and stimulates the secretion of digestive juices.
7. Seasonal and fresh fruits should be taken in between the regular meals.
8. Take medicines and food supplements as advised by your physician.

Diabetes and Pregnancy

Pregnancy brings a sea change in the metabolism in pregnant women. Your bodyhas to produce extra insulin to meet the requirements of your body during pregnancy, especially from 4^th month onwards. Hormonal changes during pregnancy may interfere with the insulin function and if your body can't cope with the situation, you may develop gestational diabetes. Women with family history of diabetes mellitus, older mothers and obese women are at the risk of developing gestation diabetes mellitus (GDM). The diabetes mellitus in pregnancy could be classified as pre-gestational or gestation diabetes mellitus. One out of fourteen cases of pregnancy may develop GDM in second or third trimester of pregnancy due to effect of placental hormones. Ideally, all pregnant women should be tested to rule out gestation diabetes. The routine examination of urine for sugar, on every visit to the gynaecologist could give an indication about onset of gestation diabetes and need for further investigations and medication. If elevated level of blood sugar is observed on random blood sugar (RBS)investigation, one should go for glucose tolerance test (GTT). Diabetic mothers need extra care to prevent spontaneous abortion and malformations in infants. Babies born to diabetic women, who were diabetic before they became pregnant, would have a greater risk of health problems, if diabetes was poorly controlled. Babies grow bigger in diabetic expectants due to extra sugar crossing the placenta and may make labour and delivery more difficult. Periodic screening, dietary control and proper medication are must to avoid GDM associated complications in expectant mothers and babies born.

Age-Related Vision Loss: Preventive Tips

Human eye is the first imaging system, the retina of which is embedded with tone sensitive and color sensitive receptors. There are around 120 million rods and 6 million cones in the retina of each eye. There are separate sets of sensitive cones for the tree primary colors and are termed as red, blue or green receptors. These receptors supply information to our brain about shape, size and color tone of the images. The central part of the retina of our eyes is called mecula that helps us to see the finer details. With ageing comes the age-related vision loss. Eyes are very delicate organ of our body and with the advancing age need extra care and dietary supplements to offset the age-related degeneration. Age-related macular degeneration(ARMD) is a disease of our eyes that causes progressive degeneration of macula. There are two common types of ARMD: 1) Atrophic or dry ARMD causes the thinning of the mecula and affects the majority of patients, 2) Exudative or wet ARMD may be hemorrhagic and is caused by the development of abnormal blood vessels beneath the epithelial layer of retina. These blood vessels may bleed and cause scarring and loss of central vision in old age. Dry ARMD causes gradual vision loss and the risk can be lowered/prevented through regular eye check-up after the age of 55 years. The early detection of ARMD is the key to save our eyes from age-related vision loss. Treatment of both types of ARMD is available in the Eye Departments/Centers of major hospitals worldwide. The risk of developing ARMD could be lowered by regular intake of Vitamin C, E, beta-carotene and zinc supplements.