Mechanism of Action of Chinese Wonder Herb discovered

chinese herb

Chang Shan, a type of hydrangea found in Tibet and Nepal has been used for thousands of years by Chinese doctors for treating malaria. The bioactive constituent of hydrangea and more than 50 other Chinese herbs is febrifugine. The derivatives of febrifugine have been found to be effective against many diseases like malaria, cancer, and various auto-immune disorders like multiple sclerosis, psoriasis, etc. Now researchers have tracked down the mechanism of action of this bioactive compound.

The researchers from the Harvard School of Dental Medicine have found that halofuginone (HF), a derivative of febrifugine, inhibits the development of TH17- driven autoimmunity. HF blocks the development of T H17 cells which are responsible for many auto-immune disorders, without harming other beneficial immune cells. While the global immunity remains unaffected, HF inhibits the auto-immunity.

Researchers have, in recent years, discovered an amino acid response (AAR) pathway in the cells. This pathway is nutrient sensing and can guide the cell to preserve resources in case of a limited supply of amino acids for building proteins. The researchers involved in the present study tried to find out the effect of HF on AAR pathway. They found that HF specifically inhibits tRNA synthetase, an enzyme required for incorporating proline, an amino acid, into the proteins. Proline is an essential amino acid. Its deficiency kick-starts the AAR response and inhibits the production of T H17 cells.

Researchers also noted that giving proline supplementation to patients taking HF reverses the therapeutic action of HF. It is no longer found to be effective in treating malaria and other auto-immune disorders.  The mechanism through which restricting proline results in a decrease in the production of T H17 cells is a subject of further studies. Similarly, the role of amino acid limitation and disease response is yet to be comprehended.

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Date: 
Saturday, February 18, 2012