Gallic acid-coated sliver nanoparticle alters the expression of radiation-induced epithelial-mesenchymal transition in non-small lung cancer cells

BACKGROUND

Radiotherapy is the most widely used treatment method for treating cancer with or without surgery and chemotherapy. In lung cancer, it is one of the important treatment steps in excising the tumor from the lung tissue; unfortunately, radiation can induce epithelial- mesenchymal transition (EMT), a typical physiological process in which cuboidal shaped epithelial cell loses its phenotype and acquires mesenchymal-like phenotype thus, increases the metastasis progression in the body. To prevent EMT mediated metastasis, we aimed to 1) synthesize silver nanoparticles by using Gallic acid, a potential antioxidant which acts as stabilizing and reducing agent in the form of silver nanoparticle (GA-AgNPs) 2) to analyze its effect on EMT markers during radiation-induced EMT in A549 cells.

METHODS

A549 cells were irradiated with 8Gy (X-ray) and treated with GA-AgNPs at a fixed concentration under in vitro condition. GA-AgNPs were prepared and characterized for absorption, potential stability, size and morphology by UV-Visible spectrophotometer, Zeta potential and Transmission electron microscopy respectively. After irradiation, the morphology changes were observed using an inverted microscope, the gene and protein expression of EMT markers were analyzed by RT-PCR and western blotting.

RESULTS/CONCLUSION

GA-AgNPs are in nano size with fair stability. The synthesized nanoparticles suppressed the EMT markers including Vimentin, N-cadherin, Snail-1 and increased E-cadherin expression which might inhibit cancer cells to acquire radio resistant metastasis potential.

Investigation of the radioprotective efficacy of hesperidin against gamma-radiation induced cellular damage in cultured human peripheral blood lymphocytes

The present study was aimed to evaluate the radioprotective efficacy of hesperidin (HN), a flavonone glycoside against gamma-radiation-induced cellular damage in cultured human peripheral blood lymphocytes. Different concentrations of HN (3.27, 6.55, 9.83, 13.10, 16.38 and 19.65 microM) were pre-incubated with lymphocytes for 30 min prior to gamma-irradiation [4 Gy] and the micronuclei (MN) scoring, dicentric aberration and comet assay were performed to fix the effective dose of HN against gamma-irradiation induced cellular damage. The results indicated that among all the concentrations, 16.38 microM concentration of HN showed optimum protection by effectively decreasing the MN frequencies, dicentric aberrations and comet attributes. Based on the above results, 16.38 microM concentration of HN was fixed as the effective dose to further investigate its radioprotective efficacy which was then carried out by pre-incubating lymphocytes with 16.38 microM concentration of HN, exposing the lymphocytes to different doses (1, 2, 3 and 4 Gy) of radiation and investigating radiation induced genetic damage (MN, dicentric aberration, comet assay, DNA fragmentation assay) and biochemical changes (changes in the level of enzymic and non-enzymic antioxidants, lipid peroxidation). The results indicated a dose dependent increase in both genetic damage and thiobarbituric acid reactive substances (TBARS), accompanied by a significant decrease in the antioxidant status compared to HN treated groups which modulated the toxic effects through its antioxidant potential. Thus the current study shows HN to be an effective radioprotector against gamma-radiation induced in-vitro cellular damage in lymphocytes.

Effect of ellagic acid, a natural polyphenol, on alcohol-induced prooxidant and antioxidant imbalance: a drug dose dependent study

INTRODUCTION

Alcohol abuse, alcohol intolerance and other alcohol-related disabilities are some of the most challenging public health problems. Alcohol, by its property of generating free radicals, causes severe damage to the membrane and affects almost all organs of the human body. Ellagic acid (EA), a natural polyphenolic compound found in fruits and nuts, possess several biological properties. Our aim was to investigate, in vivo, the antioxidant potential of ellagic acid against oxidative stress induced by alcohol intoxication.

METHODS

Female albino Wistar rats were used for the study. The toxicity was induced by administering 20 percent alcohol orally (7.9 g/kg body weight) for 45 days. Rats were treated with EA at three different doses (30, 60 and 90 mg/kg body weight) via intragastric intubations. The antioxidant property of EA was studied by assessing the activities of liver marker enzymes (gamma-glutamyl transferase and alkaline phosphatase), superoxide dismutase and catalase and the levels of vitamin E, vitamin C and reduced glutathione, nitric oxide (NO), protein carbonyl content (PCC), thiobarbituric acid reactive substances (TBARS) and hydroperoxides.

RESULTS

Oxidative stress was effectively modulated by EA co-administration. EA significantly improved the status of antioxidants and decreased TBARS, hydroperoxides, NO, PCC and liver marker enzymes at the dose of 60 mg/kg body weight when compared with the alcohol-treated group.

CONCLUSION

The study provides the antioxidant and cytoprotective properties of EA at a dose of 60 mg/kg body weight against oxidative stress induced by alcohol.