Asian Pacific Journal of Tropical Biomedicine

242-249

Authors: Yosra Raziani, Kimia Karami, Hamid Reza Mohammadi, Hossein Mahmoudvand, Mohammad Nabi Moradi, Javad Ghasemian Yadegari

Objective: To assess the effect of oral treatment of methanolic extract of the aerial parts of Astragalus adscendens in streptozotocin-induced diabetic rats. Methods: In order to induce diabetes, rats intraperitoneally received streptozotocin at 65 mg/kg. Sixty adult male Wistar rats were allocated into six groups (10 rats per each) including the healthy control group, the diabetic group as well as the diabetic group treated with Astragalus adscendens methanolic extract at 50, 100, and 200 mg/kg per day or glibenclamide (0.6 mg/kg/day) for 28 d. The effects of Astragalus adscendens methanolic extract on the levels of glucose, insulin, alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin, creatinine, urea, uric acid, total protein, albumin, triglyceride, cholesterol, α-amylase, oxidant/antioxidant enzymes, and inflammatory cytokines were evaluated. Real time-PCR was also used for measuring the gene expression of caspase-3, Bcl2, and Bax. Results: The levels of glucose, cholesterol, triglyceride, creatinine, urea, uric acid, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, bilirubin, and malondialdehyde considerably declined (P<0.001) in diabetic rats after treatment with Astragalus adscendens methanolic extract especially at a dose of 200 mg/kg. In addition, treatment with Astragalus adscendens methanolic extract noticeably increased the level of insulin, total protein, and albumin as well as improved the activities of catalase, glutathione peroxidase, and superoxide dismutase, as well as the expression levels of TNF-α, IL-1β, caspase-3, Bcl2 and Bax (P<0.001) compared to the diabetic control group. The extract also inhibited α-amylase in a dose-dependent manner with an IC50 value of 19.6 µg/mL. Conclusions: Astragalus adscendens methanolic extract shows potent antidiabetic, anti-inflammatory, anti-apoptotic, and antioxidant effects in diabetic rats. However, more studies are needed to verify the underlying mechanism of the effect of this plant extract and test its efficacy in clinical trials.

258-267

Authors: Thi Thanh Huong Le, Phu Hung Nguyen, Van Phuong Nguyen, Thy Ngoc Nguyen

Objective: To evaluate the effects of ethanol extract from Ardisia gigantifolia leaves on cell proliferation and cancer stem cell (CSC) number in gastric cancer. Methods: The inhibitory effect of Ardisia gigantifolia extract on the proliferation of MKN45 and MKN74 gastric cancer cells was assessed using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay. Non-adherent culture (3D) model was used to evaluate the effect of the extract on tumorsphere size and number. Moreover, the expression of CD44, ALDH, and p21 was determined by immunofluorescence analysis. Flow cytometric analysis was performed to evaluate cell cycle arrest and the expression of gastric CSC markers CD44 and ALDH. Real-time PCR analysis was also carried out to assess the effect of the extract on the expression of cell cycle-regulated genes. Results: Ardisia gigantifolia extract effectively inhibited cell proliferation with an IC50 of 55.7 µg/mL in MKN45 cells and 123.6 µg/mL in MKN74 cells. The extract also arrested cell cycle in the G0/G1 phase as well as significantly reduced the size and number of tumorspheres. The markedly increased expression of p21 was observed at both mRNA and protein levels in the extract-treated adherent cells and tumorspheres. In addition, Ardisia gigantifolia extract significantly reduced the number of CD44- and/or ALDH-expressing gastric CSC. Conclusions: The development of gastric CSC can be inhibited by the ethanol extract of Ardisia gigantifolia.