Invited Speaker


Discovery of Natural Anti-Infectives
M. Iqbal Choudhary and Atta-ur-Rahman
Pakistan

Natural products have served as a valuable source of molecular diversity in many drug discovery programs. Medicinal plants continue to provide new and important leads against various pharmacological targets, including cancer, HIV/AIDS, Alzheimer's, malaria, skin diseases, tropical diseases, etc.

Leishmaniasis is caused by protozoa parasites of the genus Leishmania, a biologically diverse group of flagellate parasites. Leishmaniasis is endamic in tropical and subtropical region, Afghanistan, Iran, China, Nepal, Bangladesh etc. Based on the high prevalence of Leishmaniasis in Pakistan and associated morbidity, we conducted a systemic study of folk medicine used against Leishmaniasis in Pakistan. We have isolated antileishmanial agents of natural origin and conducted screening of natural products for in vitro and animal toxicity assays. We also worked on human clinical trials of Leishmaniasis patients by applying the topical applications of new ointment based formulations. This new ointment is capable of eliminating the parasites and healing the wounds because of its anti-leishmanial activity when applied directly to the lesion [1, 2].

Multidrug resistance is a challenging problem for the healthcare sector and is very common in most important pathogens, such as vancomycin-resistant enterococci and Staphylococcus aureus. Exposure and inappropriate use of the antibiotics is the measure cause both in developed and developing regions [3]. Our study focusing on the discovery of natural and synthetic compounds, active against multidrug resistant bacteria Staphylococcus aureus and Pseudomonas aeruginosa (Resistant to almost 20 Antibiotics) have resulted in the identification of a number of new classes of potential antibiotics compounds.

Malaria is caused by genus Plasmodium and their species like P. falciparum, P. vivax, P. ovale and P. malariae. According to WHO, Malaria is among the one of the six major parasitic diseases. In Pakistan, the infection is prevalent in the coastal Baluchistan, interior of Sindh etc. The drug resistant malaria is a major health challenge for the health sector. Based on the high prevalence rate of malaria, we have conducted in vitro (Parasite lactate dehydrogenase assay) and in vivo (animal model) screening of medicinal plants extracts, pure natural product and synthetic compounds [4, 5].

References:

[1] Bhutto AM, Soomro RA, Nonaka S, Hashiguchi Y. (2003) Detection of new endemic areas of cutaneous leishmaniasis in Pakistan: A 6-year study. Int. J. Dermatol., 42(7):543-548.

[2] Atta-ur-Rahman, Samreen, Atia-tul-wahab, and M. Iqbal Choudhary. (2008) Discovery of leishmanicidal agents from medicinal plants. Pure Appl. Chem., Vol. 80, No. 8, pp. 1783-1790.

[3] Gerard D. Wright and Arlene D. Sutherland. (2007) New strategies for combating multidrug-resistant bacteria. TRENDS in Mol. Med., Vol. 13, No. 6.

[4] Devim C. U., Valecha. N., Atul. P. K., Pillai, C. R. (2001) Antiplasmodial effects of three medicinal plants: A preliminary study. Current Science, 80(8), 917-919.

[5] Biswas, K., Chattpadhyay, I., Banerjee, R. K., Bandyopadhay, U. (2002) Biological activities and medicinal properties of neem (Azadirachta indica). Current Science, 82(11), 1336-1345.