Hibiscus polyphenol‐rich extract induces apoptosis in human gastric carcinoma cells via p53 phosphorylation and p38 MAPK/FasL cascade pathway

Abstract

In view of the continuing need for effective anticancer agents, and the association of diet with reduced cancer risk, edible plants are increasingly being considered as sources of anticancer drugs. Hibiscus sabdariffa Linne (Malvaceae), an attractive plant believed to be native to Africa, is cultivated in the Sudan and Eastern Taiwan. Polyphenols had been demonstrated previously to possess antioxidative and antitumor promoting effects. In this study, investigations were conducted to examine the mechanism of the anticancer activity of H. sabdariffa L., Hibiscus polyphenol-rich extracts (HPE). Using HPLC assay, HPE was demonstrated to contain various polyphenols. HPE induced cell death of eight kinds of cell lines in a concentration-dependent manner. Among them human gastric carcinoma (AGS) cells were the most susceptible to HPE (0.95 mg/mL HPE inhibited its growth by 50%). Our results revealed that AGS cells underwent DNA fragmentation, and had an increase in the distribution of hypodiploid phase (apoptotic peak, 52.36%) after a 24-h treatment with HPE (2.0 mg/mL). This effect of HPE in AGS cells might be mediated via p53 signaling and p38 MAPK/FasL cascade pathway, as demonstrated by an increase in the phosphorylation of p53 and the usage of a specific p38 inhibitor, SB203580. Thus, our data present the first evidence of HPE as an apoptosis inducer in AGS cells and these findings may open interesting perspectives to the strategy in human gastric cancer treatment.

The Effect of Ethanolic Extract of Hibiscus sabdariffa on some Physiological and Antioxidant Parameters in Female Rabbits

“…According to the result of the present study there was significant decrease in the level of uric acid in animals treated with HS as compared with control group, this agreement with Chih et al (2012) which shows HS extract contains polyphenol, flavonoids, and anthocyanins. Antioxidant anthocyanins can potentially lower serum uric acid, polyphenols can affect the prevention of cancer and atherosclerosis, lower blood pressure, reduce inflammation and aging, and inhibit free radical activity (Kamboh et al, 2015), this suggests that HS extract may be able to lower serum uric acid (Lin et al, 2005). Also there was significant decrease in level of TAG and cholesterol in animals treated with HS as compared with control in agreement with Chen et al (2003).…”

Polyphenols Extracted fromHibiscus sabdariffaL. Inhibited Lipopolysaccharide-Induced Inflammation by Improving Antioxidative Conditions and RegulatingCyclooxygenase-2 Expression

“…Extraction of HPE was carried out as previously described. 16) Briefly, dried flower was extracted with methanol, and then the samples were filtered and concentrated with a vacuum rotary evaporator. The residue was extracted first with hexane to remove pigments, and then with ethyl acetate.…”

“…The components of HPE, including protocatechuic acid (8.83%), catechin (9.97%), EGC (10.23%), EGCG (20.20%), and caffeic acid (18.10%), were determined by HPLC analysis. 16) Activity of xanthine oxidase assay. Xanthine oxidase activity was evaluated to determine the formation of uric acid produced from xanthine.…”

Total phenolics, anthocyanins, antioxidant and pro-oxidant activity of some red fruits teas

“…The IC50 values were calculated by linear regression of plots representing the concentrations of tested tea extracts, against the percentage of free radical scavenging activities. 19 …”