Curative effect of Amorphophallus campanulatus (Roxb.) Blume. tuber on N-nitrosodiethylamine- induced hepatocellular carcinoma in rats.

In this study, we investigated the curative effect of Amorphophallus campanulatus tuber methanolic extract (ACME) on N-nitrosodiethylamine (NDEA)-induced hepatocellular carcinoma (HCC) in experimental rats. All of the rats except those in the normal control group received 0.02% NDEA orally (2 mL, 5 days/week) for the first 20 weeks of the experiment. In different treatment groups, after 20 weeks of NDEA challenge, rats were supplemented with ACME (125 and 250 mg/kg body weight, orally) for the following 28 days. In addition, a standard drug control group was supplemented with silymarin (100 mg/kg bw, orally), a known tumorsuppressive agent against HCC. Administration of ACME significantly inhibited the NDEA-induced increase of hepatic nodule incidence, nodule multiplicity, and serum biochemical indices, and improved the hepatocellular architecture in a dose-dependent manner. The biochemical analysis of hepatic tissues further demonstrated that ACME counteracts NDEA-induced oxidative stress through the restoration of antioxidant enzymes. NDEAadministered rats also showed amplified expression of proliferating cell nuclear antigen in the liver, and decreased expression of this proliferative marker was clearly observed upon the supplementation of ACME. Notably, 250 mg/kg bw ACME supplementation showed better results than the other treatment regimens; this result might be associated with the enhancement of antioxidant activity and inhibition of hepatic cell proliferation.

Chemopreventive effect of Amorphophallus campanulatus (Roxb.) blume tuber against aberrant crypt foci and cell proliferation in 1, 2-dimethylhydrazine induced colon carcinogenesis.

Colorectal cancer is one of the leading causes of cancer death, both in men and women. This study investigated the effects of Amorphophallus campanulatus tuber methanolic extract (ACME) on aberrant crypt foci (ACF) formation, colonic cell proliferation, lipid peroxidative damage and the antioxidant status in a long term preclinical model of 1, 2-dimethylhydrazine (DMH) induced colon carcinogenesis in rats. Male Wistar rats were divided into six groups, viz., group I rats served as controls; group II rats treated as drug controls receiving 250 mg/ kg body weight of ACME orally; group III rats received DMH (20 mg/kg body weight) subcutaneously once a week for the first 15 weeks; groups IV, V and VI rats received ACME along with DMH during the initiation, post- initiation stages and the entire period of the study, respectively. All the rats were sacrificed at the end of 30 weeks and the intestinal and colonic tissues from different groups were subjected to biochemical and histological studies. Administration of DMH resulted in significant (p ≤ 0.05) intestinal and colonic lipid peroxidation (MDA) and reduction of antioxidants such as catalase, glutathione peroxidase, glutathione reductase, glutathione-S- transferase and reduced glutathione. Whereas the supplementation of ACME significantly (p ≤ 0.05) improved the intestinal and colonic MDA and reduced glutathione levels and the activities of antioxidant enzymes in DMH intoxicated rats. ACME administration also significantly suppressed the formation and multiplicity of ACF. In addition, the DMH administered rats showed amplified expression of PCNA in the colon and decreased expression of this proliferative marker was clearly noted with initiation, post-initiation and entire period of ACME treatment regimens. These results indicate that ACME could exert a significant chemopreventive effect on colon carcinogenesis induced by DMH.

Protective effect of Amorphophallus campanulatus (Roxb.) Blume. tuber against thioacetamide induced oxidative stress in rats.

OBJECTIVE: To identify the phytochemical constituents of Amorphophallus campanulatus (A. campanulatus) tuber and to evaluate its antioxidant potential through in vitro and in vivo models. METHODS: Phytochemical screening and in vitro antioxidant activities of A. campanulatus tuber n-hexane extract (ACHE) and methanolic extract (ACME) were evaluated using DPPH, hydroxyl radical, reducing power and total antioxidant capacity assays. The total phenolic and flavonoid contents were also investigated. The protective potential of two different doses of ACME (125 and 250 mg/kg) was also evaluated against thioacetamide (TAA) induced oxidative stress in rats. Silymarin used as a standard drug control. Hepatotoxicity was assessed by quantifying the serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). The antioxidant potential of ACME were also evaluated by the estimation of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), reduced glutathione (GSH) and lipid peroxidation (Thiobarbituric acid reactive substances) in hepatic and renal tissues. Histopathologic changes of liver were also evaluated. RESULTS: In vitro studies revealed that ACME has higher antioxidant and radical scavenging activity than ACHE, which may be attributed to its higher phenolic and flavonoid content. ACME significantly prevented the elevation of serum AST, ALT, ALP, LDH, and tissue malondialdehyde levels(P < 0.05). Hepatic and renal GSH, GST, GR, GPx, and catalase levels were remarkably increased by the treatment with the extract. Quantification of histopathological changes also supported the dose dependent protective effects of ACME. CONCLUSIONS: The results do suggest that A. campanulatus tuber could be considered as a potential source of natural antioxidant.