Extracts from Acacia catechu suppress HIV-1 replication by inhibiting the activities of the viral protease and Tat

Abstract

BackgroundAcacia catechu (Mimosa family) stem bark extracts have been used traditionally as a dietary supplement as well as a folk medicine given its reported anti-inflammatory, immunomodulatory, hepatoprotective, antioxidant, anti-microbial and anti-tumor activities. The present study was undertaken to evaluate the anti-HIV-1 activity of the extracts from stem bark of A. catechu.MethodsThe aqueous and 50% ethanolic extracts of A. catechu stem bark were prepared and 50% ethanolic extract was further fractioned by successively partitioning with petroleum ether, chloroform and n-butanol. All the extracts and fractions were evaluated for cytotoxicity and anti-HIV-1 activity using different in vitro assays. The active n-butanol fraction was evaluated for its inhibition against HIV-1 reverse transcriptase, integrase, protease, pro-viral genome integration and viral Tat protein mediated transactivation. The effect of n-butanol fraction on the induction of pro-inflammatory cytokines secretion in Vk2/E6E7 cells and transepithelial resistance in Caco-2 and HEC-1A cells was investigated.ResultsThe aqueous and 50% ethanolic extracts of A. catechu showed IC50 values of 1.8 ± 0.18 μg/ml and 3.6 ± 0.31 μg/ml, respectively in cell-free virus based assay using TZM-bl cells and HIV-1NL4.3 (X-4 tropic). In the above assay, n-butanol fraction exhibited anti-HIV-1 activity with an IC50 of 1.7 ± 0.12 μg/ml. The n-butanol fraction showed a dose-dependent inhibition against HIV-1NL4.3 infection of the peripheral blood lymphocytes and against HIV-1BaL(R-5-tropic) as well as two different primary viral isolates of HIV-1 infection of TZM-bl cells. The n-butanol fraction demonstrates a potent inhibitory activity against the viral protease (IC50 = 12.9 μg/ml), but not reverse transcriptase or integrase. Further, in Alu-PCR no effect on viral integration was observed. The n-butanol fraction interfered with the Tat-mediated Long Terminal Repeat transactivation in TZM-bl cells, mRNA quantitation (qRT-PCR) and electrophoretic mobility shift assay (EMSA). The n-butanol fraction did not cause an enhanced secretion of pro-inflammatory cytokines in Vk2/E6E7 cells. Additionally, no adverse effects were observed to the monolayer formed by the Caco-2 and HEC-1A epithelial cells.ConclusionsThe results presented here show a potential anti-HIV-1 activity of A. catechu mediated by the inhibition of the functions of the viral protein and Tat.

Plants-Derived Biomolecules as Potent Antiviral Phytomedicines: New Insights on Ethnobotanical Evidences against Coronaviruses

“…The mechanism of action of A. arabica is known. It specifically inhibits the stage of viral intracellular multiplication [ 149 , 167 , 168 , 169 ]. Furthermore, A. arabica contains several bioactive components extracted from the leaves of the plant which are responsible for its bioactivity, such as flavonoids, methyl 3,4,5 tri hydroxyl benzoate, p -coumaroyl glucoside, p -coumaroylquinic acid, ferulic acid, isoferulic acid, epicatechin-3-gallate, ascorbic acid, quercetin 3-O-(4′-O-acetyl)-rhamnopyranoside, oleic acid, myristic acid, palmitic acid and steroidal sapogenin aglycone [ 166 , 167 , 168 , 276 ].…”

“…Furthermore, A. arabica contains several bioactive components extracted from the leaves of the plant which are responsible for its bioactivity, such as flavonoids, methyl 3,4,5 tri hydroxyl benzoate, p -coumaroyl glucoside, p -coumaroylquinic acid, ferulic acid, isoferulic acid, epicatechin-3-gallate, ascorbic acid, quercetin 3-O-(4′-O-acetyl)-rhamnopyranoside, oleic acid, myristic acid, palmitic acid and steroidal sapogenin aglycone [ 166 , 167 , 168 , 276 ]. A. arabica also has the potential to inhibit the viral replication against HIV infection [ 149 , 169 ]. Due to its antiviral nature, it is highly recommended to use A. arabica for controlling/managing SARS-CoV-2 infection.…”

Methanolic bark extract of Acacia catechu ameliorates benzo(a)pyrene induced lung toxicity by abrogation of oxidative stress, inflammation, and apoptosis in mice

“…Reports indicated that a standardized extracts produced from Acacia catechu bark extracts contain catechin, kaempferol, rutin, ferulic acid, and caeffic acid. 13 The extract is claimed to possess all the active principles of the plant. The extract was used in the present study after preliminary in vitro tests.…”

“…8 It also showed anti-lipid peroxidative and superoxide anion scavenging activity 12 Many therapeutic compounds such as catechin, kaempferol, rutin, ferulic acid and caeffic acid have been isolated from the bark of Acacia catechu. 13 The methanolic extract of Acacia catechu possesses antimicrobial potential against many microorganisms and anti-genotoxicity power. 11,14 To best of our knowledge, no work has been done on the efficacy of MEBA against lungs toxicity.…”

Unraveling Natural Products’ Role in Osteoarthritis Management—An Overview

“…Acacia catechu (Mimosa family) extracts and Mori folium, the leaves of Morus alba L., have been traditionally used as a dietary supplement or folk medicine due to the documented anti-inflammatory activity, as well as protection of the liver and hypertension, respectively [122]. The aqueous extract of Acacia catechu heartwood is a good source of catechin and epicatechin, with smaller quantities of flavonoids, which have well-documented health benefits [123], also in the context of OA as it has been observed in this review.…”