31, December 2014

Born after 1942? You are more likely to be obese!

People born before 1942 are less likely to be affected by a variant to a gene linked to obesity risk than those who are born after 1942. The effect is stronger in those born in later decades, finds a fascinating research. The findings underscores the effect of broad environmental changes to increase in obesity in recent times. Â’We found that the correlation between the best known obesity-associated gene variant and body mass index increased significantly as the year of birth of participants increased,’ said lead author James Niels Rosenquist from Massachusetts General Hospital (MGH). 

The researchers used data gathered between 1971 and 2008, when participants ranged in age from 27 to 63. Looking at the relationships between participants’ body mass index (BMI), as measured eight times during the study period, and the FTO gene variants they had inherited. The previously reported association between a specific FTO variant and BMI was seen, on average, only in participants born in later years.

  

While there was no correlation between the obesity-risk variant and BMI for those born before 1942, in participants born after 1942 the correlation was twice as strong as reported in previous studies.  Post-World War II factors such as increased reliance on technology rather than physical labour and the availability of high-calorie processed foods are likely contributors to the environmental effects of obesity, the authors noted.  

The study appeared in the journal PNAS Early Edition.

Source: www.thehealthsite.com

31.12.2014

Risk of having cancer again can be prevented by reprogramming stem cells

After full body radiation, certain faulty stem cells re-engineer the blood system that creates cancer risk in people which can be prevented by artificially activating a stem cell maintenance pathway, research has found. ‘In a healthy blood system, healthy stem cells out-compete stem cells that happen to have the C/EBPA (gene) mutation,’ said senior author James DeGregori, investigator at University of Colorado Cancer Center.

‘But when radiation reduces the heath and robustness (what we call ‘fitness’) of the stem cell population, the mutated cells that have been there all along are suddenly given the opportunity to take over,’ DeGregori added. The study does not just shows why radiation makes hematopoietic stem cells (HSCs) differentiate; it also demonstrates that by activating a stem cell maintenance pathway, it can be kept at bay. Even months after irradiation, artificially activating the NOTCH signaling pathway of irradiated HSCs lets them act ;stemmy’ again – restarting the blood cell assembly line in these HSCs that would have otherwise differentiated in response to radiation, the findings showed.

The Notch signaling pathway is an inter-cellular signaling mechanism essential for proper embryonic development. The researchers explored the effects of full body radiation on the blood stem cells of mice.In this case, radiation increased the probability that cells in the hematopoietic stem cell system would differentiate. Only, while most followed this instruction, a few did not. Genetic inhibition of the gene C/EBPA allowed a few stem cells to keep the ability to act as stem cells. With competition from other, healthy stem cells removed, the stem cells with reduced C/EBPA were able to dominate the blood cell production system.

The study appeared in the journal Stem Cells.

Source: www.thehealthsite.com

31.12.2014

It is better to be hated for what you are than to be loved for what you are not

André Gide