Comparative assessment of redox-sensitive biomarkers due to acacia honey and sodium arsenite administration in vivo

Elucidation of chemical profiles and molecular targets of Mondia whitei leave fractions bioactive as novel therapeutics: an in vitro and in silico assay

BACKGROUND

Mondia whitei root is often used in Africa as a local therapeutic agent for libido enhancement. The fractions of the M. whitei leaves (MWL) lack chemical characterization of their bioactive components and possible molecular targets. We characterized and investigated its molecular target as therapeutic agents in an in vitro and in silico assay. Mineral compositions, antioxidant, and GC-MS characterization were studied. The cytotoxicity effect was measured on HeLa and HT-29 cells by MTT assay. In silico potential inhibitors of Cathepsin B (CathB) as a cancer biomarker were determined.

RESULTS

The flame photometry produced marked Na⁺ and K⁺. GC-MS revealed eighteen bioactive components. The fractions (chloroformic 47.00, ethanolic 45.52, and aqueous 40.13) of MWL caused a higher inhibition ratio compared to standards. The MWL showed a significant cytotoxic effect on the treated cell lines at concentrations of 150 and 200 μg/ml and 100, 150, and 200 μg/ml for HT-29 and HeLa cells, respectively. Ten bioactives (MWL 4, 5, 6, 8, 9, 10, 14, 15, 17, and 18) showed potential inhibition of CathB with binding affinities of -4.40 to -8.3 Kcal/Mol. However, MWL 4, 9, 14, and 17 which have higher binding affinities (-6.7, -7.1, -8.2, and -8.3, respectively) than the standard inhibitor (-6.5) were the lead molecules.

CONCLUSION

These chemical profiles and potential molecular targets unraveled in this study propose that MWL has a promising anticancer activity.

The role of molecular modelling strategies in validating the effects of chrysin on sodium arsenite-induced chromosomal and DNA damage

Chrysin (CHR) is a food-based bioactive ingredient whereas, sodium arsenite (SA) is one of the major contaminant in drinking water. When ingested, SA contributes to tissue damage due to bioactivation by S-adenosyl methionine (SAM)-dependent methyltransferase. Hence, the needs to nullify this effect by investigating the potentials of CHR on SA-induced genotoxicity in rats. The experiment was divided into two successive stages (ameliorative and preventive, curative studies) for 1 week. Rats were divided into four groups: distilled water, 10mg/kg SA, 10mg/kg CHR and co-administration. In stage 2, the experimental groups were given either CHR or SA for 1 week, and treated in reversed order for additional week. Lipid peroxidation, protein carbonyl and DNA fragmentation in liver, blood brain and bone marrow cells micronucleus were assayed for using standard protocols. Molecular docking of SAM-dependent methyltransferase in the presence of CHR was conducted. CHR significantly ( p < 0.05) decreased the level of lipid peroxidation, protein carbonyls and DNA fragmentation in blood, liver and brain tissues as against group treated with SA. It also significantly ( p<0.05) reduced the level of micronuclei generated in bone marrow cells. The effects of CHR were shown to be ameliorative, preventive and curative in nature. Furthermore, CHR was able to dock (with binding energy of −24.81 kcal/mol and predicted inhibition kinetic constant (Ki) of 0.959 µM) into the active site of SAM-dependent methyltransferase with strong hydrogen bond and hydrophobic interactions. The study might have unravelled the potentials of CHR against SA-induced chromosomal and DNA damage, which might be due to inhibition of SAM-dependent methyltransferase.