Modulation of cigarette smoke induced alterations by aqueous Ocimum sanctum leaf extract in pulmonary tissue of rodents

Smoking has been associated with an increased risk of asthma, lung cancer, cardiovascular diseases, chronic bronchitis, and a massive amount of oxidative stress. The present study was undertaken to determine the modulatory effects of Holi Basil/Tulsi, (Ocimum sanctum) leaf extract on cigarette smoke-induced pulmonary damage in mice. Cigarette smoke (CS) inhalation increased the levels of pulmonary lipid peroxidation, and reactive oxygen species and decreased the levels of glutathione. Histoarchitectural alterations and enhanced tissue lactate dehydrogenase (LDH) activity in pulmonary tissue was distinctly indicative of damage. Enhanced mucin production was also observed through mucicarmine and Alcian Blue-Periodic Acid Schiff (PAS) staining. Increased expression of MUC5AC was also observed. Alterations in the lung were also evident through FTIR studies. Administration of Ocimum sanctum leaf extract (80 mg/kg b.w) to CS exposed mice ameliorated these alterations to a greater extent. These findings are suggestive of the fact that Ocimum sanctum leaf extract effectively modulated CS-induced deleterious effects on pulmonary tissue.

Ellagic acid modulates cisplatin toxicity in DMH induced colorectal cancer: Studies on membrane alterations

Systemic toxicity due to chemotherapy contributes to poor prognosis in patients receiving chemotherapy. The present study, therefore, explores the role of Ellagic acid, a phytochemical, in modulating cisplatin (CP) toxicity in dimethylhydrazine-induced colorectal cancer. Colons excised from DMH administered animals showed abnormal crypts and bulges over the mucosal surface. SEM revealed significant alterations and dysplastic lesions in DMH administered mice. Animals receiving combined treatment showed improvement in colonic epithelium with lesser irregularities. DMH and CP administration disturbed the membrane dynamics and integrity as observed with the fluorescent probes DPH and pyrene. However, EA co-supplementation with CP proved to be beneficial in normalizing the altered membrane. Ellagic acid co-supplementation along with CP; therefore, showed great promise and helped restore the membrane alterations in the colon caused due to CP-induced toxicity and DMH insult. These observations could pave way towards developing a combination therapy targeting colon carcinogenesis in future.

•

Colorectal tumor initiation as evident by the presence of ACFs (pre-neoplastic lesions).

•

DMH and Cisplatin altered the membrane dynamics.

•

Ellagic acid helped restore the membrane structure as evidenced through SEM.

•

Membrane dynamics were also improved, as evidenced through lipid packing and lateral diffusion.

•

Structural alterations monitored through FT-IR were also improved upon Ellagic acid co-supplementation.

Modulatory Effects of Ginkgo biloba Against Amyloid Aggregation Through Induction of Heat Shock Proteins in Aluminium Induced Neurotoxicity

Protein misfolding and aggregation of amyloid beta (Aβ) peptide, as well as formation of neurofibrillary tangles (NFTs) are the signature hallmarks of Alzheimer's disease (AD) pathology. To prevent this, molecular chaperones come into play as they facilitate the refolding of the misfolded proteins and cell protection under stress. Here, we have evaluated the possible effects of Ginkgo biloba (GBE) against aggregation of the Aβ through activation of heat shock proteins (HSPs) in the Aluminium (Al) induced AD based model. GBE (100 mg/kg body weight) was administered per oral to the female SD rats in conjunction with intraperitoneal (i.p.) injection of Al lactate (10 mg/kg body weight) for six weeks. Pretreated animals were administered GBE for additional two weeks prior to any exposure of Al. GBE administration resulted in decrease in Aβ aggregation, ubiquitin deposition, accompanying a significant decline in APP & Tau protein hyperphosphorylation which can be attributed to activation of Heat shock factor (HSF-1) and upregulation in the protein expression of HSPs. Histopathological investigation studies have also shown the decrease in aggregation of Aβ peptide by GBE administration. Additionally, the decrease in ROS levels and Aβ aggregation by GBE administration prohibited the decline in the neurotransmitter levels and monoamine oxidase levels in hippocampus and cortex. This further caused improvement in learning and memory of the animals. In conclusion, our results indicate that GBE prevents the symptoms of Al induced AD like pathophysiology by upregulating the HSPs levels and decreasing the aggregation load.

Ginkgo biloba attenuates aluminum lactate-induced neurotoxicity in reproductive senescent female rats: behavioral, biochemical, and histopathological study

Extensive use of aluminum (Al) in industry, cooking utensils, and wrapping or freezing the food items, due to its cheapness and abundance in the environment, has become a major concern. Growing evidence supports that environmental pollutant Al promotes the aggregation of amyloid beta (Aβ) in the brain, which is the main pathological marker of Alzheimer's disease (AD). Further, AD- and Al-induced neurotoxic effects are more common among women following reproductive senescence due to decline in estrogen. Though clinically Ginkgo biloba extract (GBE) has been exploited as a memory enhancer, its role in Al-induced neurotoxicity in reproductive senescent female rats needs to be evaluated. Animals were exposed to intraperitoneal dose (10 mg/kg b.wt) of Al and oral dose (100 mg/kg b.wt.) of GBE daily for 6 weeks. A significant decline in the Al-induced Aβ aggregates was observed in hippocampal and cortical regions of the brain with GBE supplementation, as confirmed by thioflavin (ThT) and Congo red staining. GBE administration significantly decreased the reactive oxygen species, lipid peroxidation, nitric oxide, and citrulline levels in comparison to Al-treated rats. On the contrary, a significant increase in the reduced glutathione, GSH/GSSG ratio as well as in the activities of antioxidant enzymes was observed with GBE administration. Based on the above results, GBE prevented the neuronal loss in the hippocampus and cortex, hence caused significant improvement in the learning and memory of the animals in terms of AChE activity, serotonin levels, Morris water maze, and active and passive avoidance tests. In conclusion, GBE has alleviated the behavioral, biochemical, and histopathological alterations due to Al toxicity in rats. However, molecular studies are going on to better understand the mechanism of GBE protection against the environmental toxicant Al exposure. Graphical abstract .

Ellagic acid ameliorates cisplatin induced hepatotoxicity in colon carcinogenesis

The clinical application of cisplatin (CP), one of the most extensively used antineoplastic drug, is restricted by its numerous side effects. CP's antitumor potential resides in the free generation of reactive oxygen species leading to oxidative stress. This stress is a source of the side effects associated with its use. Ellagic acid (EA), a polyphenol is known to possess multiple health benefits owing to its antioxidant properties. EA is largely metabolized by the colon microbiota of different mammals and therefore was a polyphenol of choice in the present study. The present study was thus carried out to explore the protective potential of EA on CP induced hepatotoxicity in colon tumor bearing mice. The administration of EA (10 mg/kg bwt po daily for 6 weeks) significantly ameliorated the toxicity caused by CP (5 mg/kg bwt ip once a week for 4 weeks). Activities of liver marker enzymes and lactate dehydrogenase were brought back to normal. EA cotreatment also led to a marked reduction in the extent of peroxidative damage to liver tissue as was evident from the improvement in the histopathological changes observed and FT-IR analysis. The present study, therefore, suggests that the administration of EA reduces the CP-induced hepatotoxicity, thereby emerging out as a potential candidate for chemopreventive action.

Curcumin sensitizes lung adenocarcinoma cells to apoptosis via intracellular redox status mediated pathway

The present study demonstrates that curcumin acts as pro-oxidant and sensitizes human lung adenocarcinoma epithelial cells (A549) to apoptosis via intracellular redox status mediated pathway. Results indicated that curcumin induced cell toxicity (light microscopy and MTT assay) and apoptosis (AnnexinV-FITC/PI labeling and caspase-3 activity) in these cells. These events seem to be mediated through generation of reactive oxygen species (ROS) and superoxide radicals (SOR) and enhanced levels of lipid peroxidation. These changes were accompanied by increase in oxidized glutathione (GSSG), reduced glutathione (GSH) and gamma-glutamylcysteine synthetase (gamma-GCS) activity, but decrease in GSH/GSSG ratio. The induction of apoptosis and decrease in GSH/GSSG ratio was also accompanied by sustained phosphorylation and activation of p38 mitogen activated protein kinase (MAPK). On the other hand, addition of N-acetyl cysteine (NAC), an antioxidant, blocked the curcumin-induced ROS production and rescued malignant cells from curcumin-induced apoptosis through caspase-3 deactivation. However, L-buthionine sulfoximine (BSO), a GSH synthesis blocking agent, further enhanced curcumin-induced ROS production and apoptosis in A549 cells. Decreased GSH/GSSG ratio seems to be a crucial factor for the activation of MAPK signaling cascade by curcumin. The study therefore, provides an insight into the molecular mechanism involved in sensitization of lung adenocarcinoma cells to apoptosis by curcumin.

Apoptosis induced by modulation in selenium status involves p38 MAPK and ROS: implications in spermatogenesis

Selenium has been linked to cell survival and apoptosis. Apoptosis plays an important role in spermatogenesis. Evidence suggests that reactive oxygen species induce apoptotic pathways. Although the mechanism by which oxidants mediate apoptosis is not well defined, the mitogen-activated protein kinase (MAPK) and caspase pathways have been implicated in apoptosis. Thus, this study was designed, keeping in view the critical balance between cell proliferation and apoptosis for normal spermatogenesis, and the requirement of selenium for the maintenance of male fertility. The intracellular selenium status was modulated by feeding selenium-deficient and -excess diet for 8 weeks. Involvement of p38 MAPK and ROS was monitored. Apoptotic factors like caspases and Bcl-2 were also analyzed. It was observed that the selenium levels were altered along with an increase in ROS generation and lipid peroxidation. mRNA expression of p38, caspases 3, and 8 increased, whereas that for Bcl-2 decreased. Western immunoblot analysis and immunohistochemical localization studies for p38 showed a similar increase. Integrity of DNA was altered in the form of apoptotic cells. Thus, the results presented in this study suggest that sodium selenite causes apoptosis and the toxicity of selenite is mediated by increase in ROS. Morevoer, ROS generation is associated with increased expression of p38, caspases 3 and 8, and decreased Bcl-2 expression. Our data indicate that p38 participates in testicular apoptosis and that selenium is required for maintenance of the critical balance between cell death and proliferation.