Lab notes: Why fidgeting is healthy, what links obesity to diabetes and a possible new malaria cure

Why obese people are more prone to diabetes

Obese people are particularly at risk of getting diabetes and the link between the two conditions lies is due to a chemical call chemerin. In what’s being called a major breakthough, scientists from the Indian Institute of Chemical Biology in Kolkata and have uncovered the mechanism by which obesity causes type 2 diabetes, also called insulin-resistant diabetes.

In an obese person – someone with a body mass index of above 30 – adipose tissue accumulates fat. Immune cells called macrophages infiltrate fat tissue producing chemicals that lead to inflammation that triggers insulin resistance. What was not known is how macrophages cause inflammation.

Working with their collaborators in ILS Hospitals and the Institute of Postgraduate Medical Education and Research, the team analysed adipose tissue samples from 83 obese individuals and 28 lean individuals undergoing bariatric and other abdominal surgeries. They found that the enlarged fat cells of an obese person release a chemical called chemerin that recruits specific immune cells called plasmacytoid dendritic cells, which in turn activate macrophages and lead to inflammation. The study was published in the journal Diabetes.

The importance of the discovery lies in its potential use in developing drugs to target chemerin and prevent the chain of cellular activity that leads to diabetes. Chemerin can also be used as a biomarker to identify which obese people maybe more prone to diabetes, the researchers say. India has a high burden of obesity with 9.8 million obese men and 20 million obese women and a growing rate of obesity even in rural areas.

Meanwhile, a study from Harvard Medical School has shown that, even though obesity increases the risk of several kinds of cancer, advanced kidney cancer progresses more slowly in obese people than in those of normal weight. An analysis of almost 2,000 patients showed that the median overall survival of overweight or obese patients was 25.6 months compared to 17.1 months for patients with low body mass indices. The mortality rate for the overweight cancer patients was 16% less than others.

Hope for a single-dose malaria drug

Treating malaria could become as simple as administering a single shot. Scientists have found that the compound bicyclic azetadine acts on all three stages of a malarial parasite to cure the disease, provide immunity through prophylaxis and prevent transmission of the disease.

Researchers at the International Centre for Genetic Engineering and Biotechnology in collaboration with researchers from Broad Institute of MIT and Harvard have found that bicyclic azetadine has targets the malaria-causing Plasmodium parasite’s protein translation, a crucial mechanism throughout its life cycle. The compound has low metabolism, long half-life and good oral bioavailability. These characteristics make it possible for the compound to be used in a single low dose.

The compound was tested and found to be effective against a number of Plasmodium strains with different resistance mechanisms. They also found that the parasite, notorious for laying low in a infected person’s blood without causing symptoms, did not reappear for 30 days after the use of bicyclic azetadine.

The findings were published in the journal Nature. The researchers say that it could take 5-7 years to make the drug commercially available.

Fidgeting keeps blood flow going

If sitting is the new smoking the fidgeting is like quitting tobacco. A new study out of the University of Missouri in Columbia demonstrates how lower-body fidgeting, like foot tapping, when seated for hours can create enough muscular activity to keep optimal levels of blood flowing through the arteries.

Long sedentary hours mandated by modern work and life causes muscular immobility and particularly affects blood vessels. Long periods of no movement in the lower body lowers blood flow and friction along blood vessel walls. This in turn makes arteries harder and narrower and raises the risk of atherosclerosis.

Researchers asked 11 college students to sit for three hours keeping one leg still while periodically moving the other leg. They measured the blood flow in both legs to find that blood flow dropped drastically in the unmoving leg but rose in the fidgeting leg compared to baseline measurements that they had taken. In their results published in the American Journal of Physiology, they also showed that after the three hours, arteries in the volunteers’ unmoving legs did not respond as well to changes in blood pressure as arteries in their fidgeting legs did.