How do Muscles Know how Much We Weigh?

Extremely overweight people often complain that it is physically hard to move.  Working with animals, scientists may have found a clue to explain that finding.  Normal weight mice show changes in the concentration of a particular muscle protein when they're fitted with heavy vests.  The increase in troponin T allows muscles to contract more strongly.

In obese mice, the gene for troponin T seemed to malfunction, and levels of muscle proteins involved in contraction were not increased.  This relative weakness can make moving more difficult, eventually leading to animals cannot move at all.

The bigger mystery, how muscles know how much you weigh and adjust their composition accordingly is still unsolved.  Troponin T may be one part of the puzzle, but clearly not the only one.

Although this research was performed in animals, it may have implications for humans.  Extremely overweight people may do better initially with exercises that do not require them to bear their whole weight, such as swimming, when compared to running.


NY Times Article

Kim Kardashian has Psoriasis

Psoriasis is a common skin disease.  The most common symptoms include red patches of skin covered with silvery scales and dry cracked skin that bleeds easily. Mild cases may be a nuisance, more severe cases can be disfiguring and disabling, especially if joints are involved in arthritis.  Psoriasis is a chronic disease, with periods of flare ups and remissions.

Heredity and environment play a role in development of the disease.  In Kim's case, her mother has had psoriasis for years.  Precise causes are not known.  The immune system appears to recognize skin cells as non-self, and attacks them.  This leads to excess skin cell growth and further activation of the immune system.

Treatment depends on the severity of the disease and can include creams that limit inflammation, vitamin D analogues and others. To make skin look and feel better, using mild soap and warm not hot water for soaking, covering affected skin overnight and small amounts of sunlight can help.

CNN Article