Design, synthesis, cytotoxic, and anti-inflammatory activities of some novel analogues of aloe-emodin isolated from the rhizomes of Rheum emodi

In connection with our continuous efforts in the synthesis of derivatives from major compounds isolated from traditional medicinal plants, in the present study we have attempted to synthesize the furan-conjugated aloe-emodin derivatives (5a-j) using a three-component reaction. The synthesized derivatives were assessed for anticancer activity against five different cancer cell lines using the in vitro MTT assay and the results showed that most of the derivatives are potent against cancer cells comparing with the control. Compounds 5a and 5e showed excellent activity against all the cancer cells with less than 12.5 µM and arrested the cell cycle at the G0/G1 phase in both CAL27 and SCC9 cells. Compound 5e induces the early apoptosis in CAL27 cells and compounds 5a and 5e induce early and late apoptosis, respectively, in SCC9 cells. Moreover, compounds 5b, 5c, 5i, and 5j showed excellent anti-inflammatory activity in LPS-stimulated RAW 264.7 cells by inhibiting IL-6 production. The molecular docking studies revealed that compound 5e has strong interaction with the CLK kinase and protein kinase II through hydrogen binding Asp325 and Lys290.

Synthesis and biological evaluation of Schizandrin derivatives as tubulin polymerization inhibitors

A series of oxime ester-derivatives were prepared by utilizing the schizandrin (1), a major compound isolated from Schisandra grandiflora, which is deployed in different traditional system of medicine. The in vitro antiproliferative activities of the synthesized compounds were assessed against a selected panel of human cancer cell lines (A549, RKO P3, DU145 and Hela) and normal cell (HEK293). Several of these derivatives were found more potent in comparison to parent compound, schizandrin (1). Particularly, 4a and 4b demonstrated potent activity against DU-145 and RKOP3 cell lines with IC₅₀ values of 3.42 µM and 3.35 µM respectively. To characterize the molecular mechanisms involved in antitumoral activity, these two compounds, 4a and 4b were selected for further studies. Cell cycle analysis revealed that both the compounds were able to induce apoptosis and cell cycle arrest at G₀/G₁ phase. To know the extent of apoptosis in DU145 and RKOP3 cell lines, Annexin V-FITC were performed. Moreover, the tubulin polymerization assay indicated that 4a and 4b exhibits potent inhibitory effect on the tubulin assembly. Molecular docking studies and competitive binding assay also indicated that 4a and 4b effectively bind at the colchicine binding site of the tubulin.

Synthesis and biological evaluation of bergenin-1,2,3-triazole hybrids as novel class of anti-mitotic agents

In continuation of our investigation of pharmacologically-motivated natural products, we have isolated bergenin (1) as a major compound from Mallotus philippensis, which is deployed in different Indian traditional systems of medicine. Here, a series of bergenin-1,2,3-triazole hybrids were synthesized and evaluated for their potentials against a panel of cancer cell lines. Several of the hybrid derivatives were found more potent in comparison to parent compound bergenin (1). Among them, 4j demonstrated potent activity against A-549 and HeLa cell lines with IC₅₀ values of 1.86 µM and 1.33 μM, respectively, and was equipotent to doxorubicin. Cell cycle analysis showed that 4j arrested HeLa cells at G2/M phase and lead to accumulation of Cyclin B1 protein. Cell based tubulin polymerization assays and docking studies demonstrated that 4j disrupts tubulin assembly by occupying colchicine binding pocket of tubulin.

Comparative cytoprotective activity of vitamin C, E and beta-carotene against chromium induced oxidative stress in murine macrophages

The present study reports the cytoprotective efficacy of vitamin C, E and beta-carotene against chromium (VI) induced oxidative stress in murine macrophages. Addition of chromium (VI) resulted in enhanced cytotoxicity as revealed by fall in neutral red uptake and increase in LDH release compared to control cells. Further there was an appreciable increase in apoptosis, ROS production and fall in reduced glutathione (GSH), glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities. Chromium also inhibited macrophage proliferation and phagocytic activity. Addition of vitamin C but not vitamin E and beta-carotene inhibited chromium induced cytotoxicity, ROS generation and apoptosis. Vitamin C significantly inhibited NO production, enhanced macrophage proliferation and phagocytic activity while vitamin E and beta-carotene had marginal effect.

The incidence of inherited defects of colour vision in Madhya Pradesh, India

1. Sex-linked type of defective colour vision among 608 unrelated students, including 251 males and 357 females belonging to different communities residing in Madhya Pradesh of India, was investigated. Males were found to have 3.19% defective colour vision; again, of the defectives the deutans were found to be exactly three times greater than the protans. Significantly, none of the females was colourblind.

2. Brahmin of Madhya Pradesh displayed a comparatively low value of abnormal incidence being 2.88% among the other Brahmin samples. The occurrence of green-blind was found to be a little more than double of the red-blind in the sample, χ2 test for significance in respect of the total incidence of colour-blindness in various samples of Brahmin shows no heterogeneity (P>0.05). But, when certain Brahmin samples having a common origin are combined, some significant differences are brought out showing a clear statistical heterogeneity (P<0.02).