Apoptotic role of marine sponge symbiont Bacillus subtilis NMK17 through the activation of caspase-3 in human breast cancer cell line.

The aim of the present study was to evaluate the diverse potential biological activity of partially purified crude extract (PPCEBS) of marine Bacillus subtilis NMK17 associated with marine sponge Clathria frondifera. Symbionts were isolated from a marine sponge, only the potential strain which exhibited apoptosis was sequenced using 16S rRNA and extract of the active strain was subjected to purification using HPLC. The potential pro-apoptotic role of PPCEBS was investigated in MCF-7 human breast cancer cell line for cytotoxicity by MTT assay, which showed dose-dependent cytotoxicity on 24 h of exposure. The apoptotic findings demonstrated that PPCEBS significantly induces apoptosis, which was characterised by apoptotic morphological changes. Further, an increased expression of the Caspase 3 and Bax whereas decreased Bcl-2 was confirmed by immunofluorescence and western blotting analysis in MCF-7 cell line, which revealed that PPCEBS has potent apoptosis-inducing property. Added to the desirable apoptotic activity, PPCEBS exhibited excellent antibacterial and antioxidant activities too. The pharmacological effect of the marine sponge-associated bacteria from Gulf of Mannar India needs further attention in discovering new bioactive compounds. Our results suggested that the compounds present in the PPCEBS in marine bacterial B. subtilis NMK17 could be candidates for developing an apoptosis-specific drug with minimal toxicity. This study indicated that marine sponge-associated bacteria could be a good source to find the cytotoxic metabolites which would induce apoptosis and cause cancer cell death. Also, this study explores that marine natural products as a potential source of pharmaceuticals.

Chemopreventive effect of myrtenal on bacterial enzyme activity and the development of 1,2-dimethyl hydrazine-induced aberrant crypt foci in Wistar Rats.

Colon cancer remains as a serious health problem around the world despite advances in diagnosis and treatment. Dietary fibers are considered to reduce the risk of colon cancer as they are converted to short chain fatty acids by the presence of anaerobic bacteria in the intestine, but imbalanced diet and high fat consumption may promote tumor formation at different sites, including the large bowel via increased bacterial enzymes activity. The present study was conducted to characterize the inhibitory action of myrtenal on bacterial enzymes and aberrant crypt foci (ACF). Experimental colon carcinogenesis induced by 1,2-dimethylhydrazine is histologically, morphologically, and anatomically similar to human colonic epithelial neoplasm. Discrete microscopic mucosal lesions such as ACF and malignant tumors function as important biomarkers in the diagnosis of colon cancer. Methylene blue staining was carried out to visualize the impact of 1,2-dimethylhydrazine and myrtenal. Myrtenal-treated animals showed decreased levels of bacterial enzymes such as ß-glucuronidase, ß-glucosidase, and mucinase. Characteristic changes in the colon were noticed by inhibiting ACF formation in the colon. In conclusion, treatment with myrtenal provided altered pathophysiological condition in colon cancer-bearing animals with evidence of decreased crypt multiplicity and tumor progression.

Anti-Oxidative Effect of Myrtenal in Prevention and Treatment of Colon Cancer Induced by 1, 2-Dimethyl Hydrazine (DMH) in Experimental Animals

Colon cancer is considered as the precarious forms of cancer in many developed countries, with few to no symptoms; the tumor is often diagnosed in the later stages of cancer. Monoterpenes are a major part of plant essential oils found largely in fruits, vegetables and herbs. The cellular and molecular activities show therapeutic progression that may reduce the risk of developing cancer by modulating the factors responsible for colon carcinogenesis. Colon cancer was induced with DMH with a dose of (20 mg/Kg/body weight) for 15 weeks by subcutaneous injection once in a week. Myrtenal treatment was started with (230 mg/Kg/body weight) by intragastric administration, one week prior to DMH induction and continued till the experimental period of 30 weeks. The Invivo results exhibit the elevated antioxidant and lipid peroxidation levels in DMH treated animals. The Histopathological analysis of colon tissues well supported the biochemical alterations and inevitably proves the protective role of Myrtenal. Treatment with myrtenal to cancer bearing animals resulted in a remarkable increase in the inherent antioxidants and excellent modulation in the morphological and physiological nature of the colon tissue. It is thus concluded that myrtenal exhibits excellent free radical scavenging activity and anticancer activity through the suppression of colon carcinoma in Wistar albino rats.