Washington/Thiruvananthapuram (ISJ) -- US scientists have uncovered the chemical process behind anti-cancer properties of a spicy Indian pepper plant, called long pepper, whose medicinal properties date back thousands of years.
The secret lies in a chemical called Piperlongumine (PL), which has shown activity against many cancers including prostate, breast, lung, colon, lymphoma, leukemia, primary brain tumours and gastric cancer.
Using X-Ray crystallography, researchers were able to create molecular structures that show how the chemical is transformed after being ingested. PL coverts to hPL, an active drug that silences a gene called GSTP1. The GSTP1 gene produces a detoxification enzyme that is often overly abundant in tumours.
X-ray crystallography allows scientists to determine molecular structures that reveal how molecules interact with targets ? in this case how PL interacts with GSTP1. Viewing the structures helps in developing drugs for those targets.
?We are hopeful that our structure will enable additional drug development efforts to improve the potency of PL for use in a wide range of cancer therapies,?said Dr. Kenneth Westover, Assistant Professor of Biochemistry and Radiation Oncology at University of Texas Southwestern Medical Centre. ?This research is a spectacular demonstration of the power of x-ray crystallography.?
Long pepper (Piper longum) or Pippali or Thrippali as is known in south India, was first referenced in ancient Ayurvedic texts, where medicinal and dietary uses were described. Long pepper, commonly found in India, is used as a spice in some Indian, North American, Indonesian and Malaysian foods, but is rarely used in European dishes.
?The study illustrates the importance of examining and re-examining our theories. In this case we learned something fundamentally new about a 3,000-year-old medical claim using modern science,? said Dr. Westover.
?Pippali is an important drug in Ayurveda. It is one of the ingredients of Trikatu, the three pungents. It is used in digestive disorders, respiratory disorders and also for diseases of the liver. Studies have shown that Pippali can enhance bioavailability of other drugs. For this reason, Pippali is added to many formulations before administration,? Dr. Ram Manohar, Director-Research, Amrita School of Ayurveda in Kerala told Indian Science Journal.
?But the most important finding about Pippali in Ayurveda is said to be a powerful Rasayana. Substances that have Rasayana property can work as immunomodulators, help in regeneration of cells and organs and also can work at the level of the genes,? said Dr. Manohar. ?The modern discovery of the use of Pippali in cancer seems to echo the Rasayana properties of this drug.?
Rasayana is a special type of treatment containing various methods of rejuvenation. It derives from 'Rasa' and 'Ayana.' The literal meaning of Rasa is the essence of something. Anything ingested into the body in the form of food or medicine is first resynthesized into Rasa Dhatu, the basic plasma tissue.
Pippali as a Rasayana has been found to be effective in chronic and debilitating diseases of the lungs and liver including cancer in clinical practice, said Dr. Manohar.
To get such benefits, Pippali has to be administered as a Rasayana. Some precautions have to be taken to help the body to withstand the strong action of drug. This procedure of administration is called Vardhamana Pippali Rasayana. Pippali is administered in small dose, which is gradually increased to a specific dosage and then reduced and tapered, he added.
Source (Part): UT Southwestern Medical Centre
Image: ISJ Archive
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