Antileishmanial activity, cytotoxicity and cellular response of amphotericin B in combination with crotamine derived from Crotalus durissus terrificus venom using in vitro and in silico approaches

OBJECTIVE

To investigate the in vitro activity, synergism, cytotoxicity and cellular immunological response, as well as the molecular affinity between amphotericin B (AmB) and crotamine (CTA), derived from Crotalus durissus terrificus venom against Leishmania amazonensis.

METHODS

This study performed the inhibition of promastigotes and amastigotes' growth under different concentrations of the drug and pharmacological combinations (AmB + CTA) based on the Berimbaum method (synergism study). The lactate dehydrogenase (LDH) quantification method was used to determine the cytotoxicity of the drug and combinations employing four cell lines (J774, HepG2, VERO, and C2C12). Following, the levels of Tumour Necrose Factor-alpha (TNF-α) and Interleukin-12 (IL-12) cytokines, using enzyme-linked immunosorbent assay (ELISA) and nitrites, as an indirect measure of Nitric Oxide (NO), using the Griess reaction were assessed in the supernatants of infected macrophages. In silico approach (molecular docking and dynamics) and binding affinity (surface plasmon resonance) between the drug and toxin were also investigated.

RESULTS

CTA enhanced AmB effect against promastigote and amastigote forms of L. amazonensis, decreased the drug toxicity in different cell lines and induced the production of important Th1-like cytokines and NO by infected macrophages. The pharmacological combination also displayed consistent molecular interactions with low energy of coupling and a concentration-dependent profile.

CONCLUSION

Our data suggest that this pharmacological approach is a promising alternative treatment against L. amazonensis infection due to the improved activity (synergistic effect) achieved against the parasites' forms and to the decreased cytotoxic effect.

Plasma Cytokine Levels in Overweight Versus Obese Disease-Free Perimenopausal Women

OBJECTIVE

To evaluate the plasma cytokine levels during T cell-mediated inflammatory responses and compare the metabolic markers between overweight and obese perimenopausal women without systemic diseases.

METHODS

Sixty perimenopausal women were divided into two groups (overweight and obese). Participants in both groups had their waist-to-height ratio (WHtR) measured and blood samples collected for the evaluation of estradiol, fasting glucose, leptin, high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, IL-10, IL-17A levels, and lipid profile.

RESULTS

In univariate analysis, women with obesity showed increased WHtR, fasting glucose, leptin, and IL-6 (p < 0.05) levels; however, significant differences were not observed in IL-10 or IL-17A (p > 0.05) levels. In the receiver operating characteristic curve, the highest areas under the curve were shown for leptin (0.856) and IL-6 (0.706). IL-6 levels correlated with both hs-CRP (r = 0.302, p = 0.020) and leptin (r = 0.294, p = 0.022). However, in multivariate analysis, IL-6 was not associated with a greater likelihood of obesity (OR = 1.61; 95% CI: 0.82-3.15; p = 0.16), when potential confounders were considered.

CONCLUSION

IL-6 levels varied between overweight and obese perimenopausal women, and this association was weaker when adjusted for other clinical variables.