In vivo antileishmanial activity and chemical profile of polar extract from Selaginella sellowii

The polar hydroethanolic extract from Selaginella sellowii (SSPHE) has been previously proven active on intracellular amastigotes (in vitro test) and now was tested on hamsters infected with Leishmania (Leishmania) amazonensis (in vivo test). SSPHE suppressed a 100% of the parasite load in the infection site and draining lymph nodes at an intralesional dose of 50 mg/kg/day × 5, which was similar to the results observed in hamsters treated with N-methylglucamine antimonate (Sb) (28 mg/Kg/day × 5). When orally administered, SSPHE (50 mg/kg/day × 20) suppressed 99.2% of the parasite load in infected footpads, while Sb suppressed 98.5%. SSPHE also enhanced the release of nitric oxide through the intralesional route in comparison to Sb. The chemical fingerprint of SSPHE by high-performance liquid chromatography with diode-array detection and tandem mass spectrometry showed the presence of biflavonoids and high molecular weight phenylpropanoid glycosides. These compounds may have a synergistic action in vivo. Histopathological study revealed that the intralesional treatment with SSPHE induced an intense inflammatory infiltrate, composed mainly of mononuclear cells. The present findings reinforce the potential of this natural product as a source of future drug candidates for American cutaneous leishmaniasis.

Antiviral activity and mechanism of action of arbidol against Hantaan virus infection

Purpose: To investigate the activity and mechanism of action of arbidol against Hantaan virus (HTNV) activity by modulating inflammation via TLR-4 pathway. Methods: HUVEC cells infected with HTNV 76-118 were treated with serially diluted arbidol solutions at -2h (2 h before viral infection, pre-treatment mode), 0 h (at the same time as viral infection, simultaneous treatment mode) or 2 h (2 h after viral infection, post-treatment mode). The transcript levels of TLR4 were detected by semi-quantitative reverse transcription-PCR (RT-PCR) at 6, 12, 18, and 24 h later. The levels of iNOS and TNF-α were examined using enzyme-linked immunosorbent assay (ELISA). Results: Pre-treatment with arbidol, rather than simultaneous treatment or post-treatment, effectively inhibited up-regulation of cellular TLR4 expression (up to 40 ± 6.1 % inhibition) and activity of supernatant iNOS induced by HTNV infection(up to 44.1 ± 9.4 % inhibition), as well as in a LPSstimulated inflammatory endothelial cell. Arbidol decreased the elevated TNF-α levels induced by LPS stimulation. Conclusion: These results are the first evidence that arbidol modulates viral PRRs signaling and its consequential inflammatory cytokine/chemokine response during hantavirus infection.

In vivo analgesic activity and safety assessment of Vitis vinifera L and Punica granatum L fruits extracts

Purpose: To investigate the analgesic properties of fruit extracts of Vitis vinifera (grape) and Punica granatum (pomegranate) in Albino mal mice. Methods: The analgesic activity of fruit extracts of V. vinifera and P. granatum were examined in vivo using thermal stimulus assays (i.e., tail immersion and hot plate) and acetic acid-induced writhing test using acetylsalicylic acid (0.1 g/kg, per os) as standard. The extracts were administered orally in doses of 1.0, 2.0 and 3.0 g/kg. Results: In acetic acid writhes test, both fruit extract pretreatments (1.0, 2.0 and 3.0 g/kg, per os) significantly decreased the number of writhes (p < 0.0001) in a dose-dependent manner compared to control. The Index of Pain Inhibition (IPI) values following V. vinifera extract treatments were 36.52 % (1.0 g/kg), 66.67 % (2.0 g/kg) and 89.71 % (3.0 g/kg) which were significantly different from those for P. granatum extracts (45.39 %, 1.0 g/kg), 70.93 %, 2.0 g/kg) and 86.88 %, 3.0 g/kg) at equivalent doses of 2.0 and 3.0 g/kg of the extracts The fruit extracts of both species increased the reaction latency time. In tail-immersion assay, only the fruit extract of P. granatum significantly increased the response to heat stimulus at doses of 2.0 g/kg (p < 0.05). Conclusion: The hydroalcohol fruit extracts of P. granatum and V. vinifera have potential analgesic effects. Further studies are needed to determine the active component responsible for this effect.