Indian Institute of Technology Kharagpur

About: Indian Institute of Technology Kharagpur is a education organization based out in Kharagpur, India. It is known for research contribution in the topics: Natural rubber & Dielectric. The organization has 16887 authors who have published 38658 publications receiving 714526 citations.

Studies on the interaction of diacetylcurcumin with calf thymus-DNA

Abstract: Ongoing research on curcumin and its structural derivatives are a subject of growing interest because of their demonstrated biological properties. Diacetylcurcumin (DAC), a synthetic derivative of natural non-toxic curcumin has been shown to affect a host of activities ranging from wound healing to life threatening diseases like AIDS, cancer etc. The interaction of diacetylcurcumin (DAC) with calf thymus-DNA (ct-DNA) has been investigated by spectroscopic and viscometric techniques. The fluorescence intensity of DAC was quenched by ct-DNA. The mean binding constant obtained from the spectroscopic techniques was 3.97 ± 0.31 × 105 M−1. Circular dichroism studies did not reveal any unwinding of the DNA helix on interaction with DAC, implying no conformational changes. The binding mode was analyzed by competitive binding between ethidium bromide (EB) and DAC for ct-DNA and also by viscometric studies. DAC was found to be a minor groove binder with a preference for the A-T region compared to the G-C region. This was substantiated by displacement studies with Hoechst 33258, a known minor groove binder. Docking studies were found to corroborate the experimental results.

Antineoplastic and apoptotic potential of traditional medicines thymoquinone and diosgenin in squamous cell carcinoma.

Abstract: Thymoquinone (TQ) and diosgenin (DG), the active ingredients obtained from black cumin (Nigella sativa) and fenugreek (Trigonella foenum graecum), respectively, exert potent bioactivity, including anticancer effects. This study investigated the antineoplastic activity of these agents against squamous cell carcinoma in vitro and sarcoma 180–induced tumors in vivo. TQ and DG inhibited cell proliferation and induced cytotoxicity in A431 and Hep2 cells. These agents induced apoptosis by increasing the sub-G1 population, LIVE/DEAD cytotoxicity, chromatin condensation, DNA laddering and TUNEL-positive cells significantly (P<0.05). Increased Bax/Bcl-2 ratio, activation of caspases and cleavage of poly ADP ribose polymerase were observed in treated cells. These drugs inhibited Akt and JNK phosphorylations, thus inhibiting cell proliferation while inducing apoptosis. In combination, TQ and DG had synergistic effects, resulting in cell viability as low as 10%. In a mouse xenograft model, a combination of TQ and DG significantly (P<0.05) reduced tumor volume, mass and increased apoptosis. TQ and DG, alone and in combination, inhibit cell proliferation and induce apoptosis in squamous cell carcinoma. The combination of TQ and DG is a potential antineoplastic therapy in this common skin cancer.