Pharmacological expression of Rasayanakarma.

Rasayana (rejuvenation) and Vajikarana (promotion of fertility and libido) therapies are very useful for maintenance of the positive health and prevention of diseases as both the therapies invigorate (Urjaskara) a healthy person. Rasayana therapy delays the process of decaying biological factors (enumerated decade wise)[12] by improving the health of individuals.

Aging is a natural inevitable phenomenon and the changes of aging are to be controlled in a systematic manner with the help of Rasayana therapies. Administration of Rasayana is time bound and is not effective in advanced stages of one's life. The activities of Rasayana drugs will be appreciated with a proper execution of prerequisite measures i.e., Purificatory procedures (Panchakarma).

The drugs intended for this purpose are currently explored under the various pharmacological contexts such as anti-ageing, antioxidant, cognitive enhancers and nootropic, adaptogenic, immunomodulators, etc.

Anti-ageing intervention is aimed at slowing down the ageing process so as to extend the functional life of a person and not merely the life span. This, in turn, implies that all physiological processes of specialized tissues are able to function in an integrated fashion.[3] Longevity is expected as a consequence of slower ageing, but the reverse may not be true. Charaka identified ten such drugs and listed them under Vayasthapana Dashemani.[4]

Adaptogens are conceptualized as a “new class of metabolic regulators which increase the ability of an organism to adapt to environmental factors.”[5] The concept of adaptogenic activity was originally created by the pharmacologist N.V. Lazarev in 1947[6] does not fit easily into the Western model of medicine and the scientific community questions the validity of this concept. It is applied to describe remedies that increase the resistance of organisms and individuals to stress in experimental as well as clinical studies. Certain experimental studies have reported few adaptogenic drugs viz., Asperagus recemosus, Bacopa monniera, Crocus sativus, Curculigo orchioides, Emblica officinalis, Ocimum sanctum, Tinospora cardifolia and Withania sominefera.[7]

Scientists are evincing great interest in screening classical Rasayana drugs for their antioxidant activity and a good number of plants shows significant evidences. Triphala has been found to be an excellent scavenger of hydroxyl radicals and nitric oxide radicals, whose excessive formation is implicated in oxidative stress.[8]

It was remarkable to note that the drugs such as Asperagus recemosus, Boerhavia diffusa, Centella asiatica, Emblica officinalis, Terminalia chebula, Tinospora cordifolia possessed significant free radical quenching and other antioxidant attributes in consonance with the traditional view of Vayasthapana when they were subjected to measure of modern scientific scrutiny.[9]

Researches on Amalaki Rasayana[10] in enhancing longevity on Drosophila melanogaster[11] fly model shows the evidence that reducing oxidative damage can extend lifespan which justifies the claim of Rasayana therapy.

Immunomodulators are a group of drugs which can regulate the immune system (stimulation, suppression or normalizing the immunological response) of an organism by interfering with its function.[12] Withanolides, the constituent of Withania somnifera have found to have immunomodulatory action. Some of the simple withanolides have immunosuppressive activity while some glycowithanolids (sitoindosides) display immunostimulation. Drugs such as Acorus calamus, Emblica ribes, Holarrhena antidysentrica, etc., are also reported to possess immunomodulatory activity.[13]

The concept of Medhyarasayana (drugs purported to act on higher mental functions) can be understood under the concepts of cognitive enhancers and nootropics. Cognitive enhancers are drugs, supplements, nutraceuticals and functional foods that enhance attention, control and memory.[1415] Nootropics are by definition cognitive enhancers, but a cognitive enhancer is not necessarily a nootropic. These are thought to work by altering the availability of the brain's supply of neurochemicals (neurotransmitters, enzymes and hormones), by improving the brain's oxygen supply, or by stimulating nerve growth. Picrosides I and II constituents of P. kurroa, have shown to potentiate nerve growing factor in cultured PC12D cells.[16]

Incorporation of Rasayana therapy in the management of certain life-style disorders such as cancer, diabetes, hypertension, osteo-arthritis and obesity can play a crucial role. So far no evidence based study has been published about the Ayurvedic drugs which can cure cancer. However when used as an adjuvant the Ayurvedic Rasayana drugs have shown significant effects in reducing the adverse effects of radiotherapy and chemotherapy in cancer.[17]

Stem cell research has led to formulate a new branch of medicine named as regenerative medicine which plays a similar role that of Rasayana therapy.[18]

In the light of scientific validation produced about various activities of Rasayana drugs, it may be possible to categorize Rasayana drugs into organ specific vitalizers viz., Brahmi, Mandukaparni, Shankhapushpi for higher mental functions, Arjuna, Pushkaramoola, Guggulu for improving and protecting cardiac function, Bharangi, Vasa, Kantakari in improving the functioning of the respiratory system, Katuki, Pippali, Bhumyamalaki to improve Liver and Spleen function, Punnarava, Gokshura and Bhunimba for conditioning urinary system, Ashoka, Ashwagandha, Shatavari, Kumari for protecting and enhancing the functions of female reproductive organs, Kapikachchu, Ashwagandha, Gokshura for protecting and enhancing the functions of male reproductive organs and Manjishta, Chandana, Haridra for protecting and promoting skin health.

Ghritha (clarified butter) and Ksheera (milk) which are included under Rasayana substances may be preferred as Anupana (vehicle) during intake of Rasayana drugs.

The drugs possessing Jivaniya, Balya, Brihmaniya, Kantya, Varnya and Sanjnasthapana may represent various pharmacological activities attributed to Rasayanakarma.

Pharmacological profiles in terms of activities described above partly substantiate the spectrum of activities of Rasayana drug and some more methods of evaluation for validating the other activities such as Indriyabala (strength to sense organs), Medha and Smriti (intellect and memory enhancement) are required which may facilitate to interpret it in totality.

The current issues includes clinical research articles dealing on the role of Medhya Rasayana and Yoga in improving the short term memory in school going children and safety profile of Virechanakarama with respect to serum electrolyte levels. Among the pharmacological researches works, observations of three Ayurvedic drugs for their antidiabetic activities have been included. Case study on the effect of Basti in the management of cough due to Pertussis is also quite interesting. A total of 10 clinical research, six pharmacological research, three pharmacognostical and phytochemical research studies and a case report are being published in this issue.