Anti-HIV-1 activity, protease inhibition and safety profile of extracts prepared from Rhus parviflora.
BACKGROUND
In the present study, extracts prepared from the leaves of Rhus parviflora Roxb. (Anacardiaceae) were evaluated for their anti-HIV activity, which have been traditionally used for the treatment of neurological disorders such as anxiety, insomnia and epilepsy.


METHODS
Aqueous and 50% ethanolic extracts prepared from leaves of the plant were tested for their cytotoxicity and anti-HIV property using reporter gene based assays as well as human peripheral blood lymphocytes (PBLs). Further these extracts were evaluated for their ability to inhibit HIV-1 reverse transcriptase (RT) and protease activity. Safety profile of the extracts was determined on viability of Lactobacillus sp., secretion of pro-inflammatory cytokines by vaginal keratinocytes and transepithelial resistance.


RESULTS
Both aqueous (IC50 = 15 μg/ml) and 50% ethanolic (IC50 = 26 μg/ml) extracts prepared from leaves of R. parviflora showed anti-HIV activity in TZM-bl cells wherein the virus was treated with the extracts prior to infection. Further, both the extracts also inhibited virus load in HIV infected CEM-GFP cells and human PBLs. The anti-HIV activity is mediated through inhibition of HIV-1 protease activity. Both the extracts did not disturb the integrity of monolayer formed by intestinal epithelial Caco-2 cells. The extracts when tested up to 100 μg/ml did not significantly reduce the viability of L. plantarum, L. fermentum, L. rhamnosus and L. casei. The extracts (100 μg/ml) did not reveal any cytotoxic effect on vaginal keratinocytes (Vk2/E6E7). Levels of pro-inflammatory cytokines secreted by Vk2/E6E7 cells treated with both the plant extracts were within the non-inflammatory range.


CONCLUSIONS
The studies reported herein showed in vitro anti-HIV activity and preliminary safety profile of the extracts prepared from the leaves of R. parviflora.
Manoj
M
Modi
Nutan
Boskey
B
Pancholi
Shweta
S
Kulshrestha
Ajay Kumar
AK
Rawat
Swadesh
S
Malhotra
Satish
S
Gupta
D018938:Caco-2 Cells; D005260:Female; D015658:HIV Infections / Q000821:virology*; D016333:HIV Protease / Q000378:metabolism*; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D015497:HIV-1 / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D010936:Plant Extracts / Q000009:adverse effects / Q000494:pharmacology*; D018515:Plant Leaves; D011480:Protease Inhibitors / Q000494:pharmacology*; D029045:Rhus / Q000009:adverse effects
D010936:Plant Extracts; D011480:Protease Inhibitors; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; D016333:HIV Protease; C514803:p16 protease, Human immunodeficiency virus 1