RETRACTED ARTICLE: Asiatic acid attenuates pre-neoplastic lesions, oxidative stress, biotransforming enzymes and histopathological alterations in 1,2-dimethylhydrazine-induced experimental rat colon carcinogenesis
Authors: Aktarul Islam Siddique
Nisha Susan Thomas
Sivaranjani Arivalagan
Vijay Mani
Nalini Namasivayam
Journal: Toxicology Mechanisms and Methods (2017)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: 1,2-Dimethylhydrazine; Albino Wistar rats; Asiatic acid; chemoprevention; colon cancer
Affiliations: Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar, India

Abstract:  Asiatic acid (AA), a pentacyclic triterpenoid, derived from the tropical medicinal plant Centella asiatica is known to exhibit numerous pharmacological properties. We hypothesized that AA will have chemopreventive potential against 1,2-dimethylhydrazine (DMH)-induced experimental colon carcinogenesis in male Wistar rats. Rats were arbitrarily divided into six groups. Group I rats were processed as control. Group II rats received AA (8 mg/kg b.w., p.o.) and groups III-VI rats received subcutaneous injections of DMH (20 mg/kg b.w.) once a week, for the first four weeks. In addition, groups IV-VI rats received AA at the doses of 2, 4 and 8 mg/kg b.w., respectively, for 16 weeks. Our results discovered that supplementation with AA to the DMH-exposed rats significantly decreased the incidence of polyps and Aberrant crypt foci (ACF) as compared to the DMH-alone-exposed rats. Moreover, in the AA-supplemented DMH-exposed rats, we ascertained increased activities of the antioxidants and decreased levels of lipid peroxidation (LPO) in the liver and circulation and enhanced levels of both LPO and antioxidants in the colon, which were altered in the DMH-alone-exposed rats. Furthermore, we also observed altered activities of vitamins C and E and biotransforming enzymes in DMH-alone-exposed rats, which were reversed on AA supplementation. All the observations were supported by our histological findings. Thus, we can conclude that, AA could be used as an effective chemopreventive agent against DMH-induced colon carcinogenesis. 

Retracted: Yes

PubPeer comments:
 The figure labeling in my version of the manuscript appears to be missing, so I am not sure which figure number this is, or what each panel is representing. In what I assume is Figure 3, panels A and Ai appear to overlap with panels B and Bi, respectively. Shown with red and blue boxes. In addition, panels E and Ei appear to overlap with panels F and Fi, respectively. Shown with pink and green boxes. ![file] , 
 The figure shown above, by Dr. Bik, is Figure 9. However, Figure 3 (Topographical view of normal crypts and aberrant crypt foci (ACF)) does appear to contain overlap, as shown below in red yellow boxes: ![file] , 
 February 2021 retraction: https: www.tandfonline.com doi full 10.1080 15376516.2021.1883264  The article is being retracted due to image manipulation in Figures 3 and 9, as follows: Figure 3: Panel E is a subsection of Panel B; Figure 3: Panels C and D appear to contain clone stamps; Figure 9: Panels A and B are the same image, with the frame of reference shifted; Figure 9: Panels Ai and Bi are the same image, with the frame of reference shifted; Figure 9: Panels E and F contain an overlapping section (panel E lower right corner, panel F upper left corner); Figure 9: Panels Ei and Fi contain an overlapping section (panel Ei lower right corner, panel Fi upper left corner). These findings are not explained by the content of the article and the authors were not able to provide original data that would support the integrity of their research. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as u201cRetractedu201d. ,