A Purified Fraction of Ocimum tenuiflorum (L) Inhibits LTC4, LTA4 and COX-2 Activities, Down-Regulates mRNA Expression in HL-60 Cells and Reduces Lung Inflammation in an OVA Induced Asthma Model in BALB/c Mice

Background: Now-a-days, discovery of bioactive compounds of plant origin is playing very important role in treatment of various ailments without any side effect world widely. Since, time immemorial, plants have been utilized as a source of Traditional System of Medicine and in India, one of the well known system is Ayurvedic System of Medicine that has been flourishing since thousands years for treatment of allergy, asthma and other inflammatory diseases. Objectives: To inhibit leukotrienes by a purified fraction of Ocimum tenuiflorum in HL- 60 cell lines. To investigate anti-inflammatory activities of a purified Fraction of Ocimum tenuiflorum in an OVA induced asthma model in BALB/c mice. Methods: Plant materials of Ocimum tenuiflorum whole plants were collected after identification and authentication from Vidisha, (M.P.), India and were shade dried, pulverized to powder and extracted after de-fatting in MEOH and DCM and then tested for LTC4, LTA4 and COX-2 inhibitory activities in HL-60 Cell lines. RTPCR was performed to determine the LTC4-synthase mRNA expression. The bio-active purified fraction PM-OT was then tested in vivo in an OVA-induced asthma model in BALB/c mice and inhibition of inflammation was assessed via in vivo imaging tomography. Results: The PM-OT inhibited activities of LTC4 by 52%, LTA4 by 25% and COX-2 by 99% in HL-60 cells and LTC4-synthase mRNA expression in HL-60 Cells. Intra-gastric administration of PM-OT at 100mg/kg body weight along with HPMC led to a reduction in an OVA-induced lung inflammation in asthma model in BALB/c mice. Conclusion: A purified PM-OT fraction showed significant anti-inflammatory activities both in vitro and in vivo, which supported its traditional use in the treatment of inflammatory lung disease and asthma.