Chemopreventive potential of Solanum Lycocarpum on colon Carcinogenesis induced in Wistar Rats

Abstract

Material and Methods:A structured search of the Cochrane Library and PubMed was conducted to identify English-language reviews, systematic as well as non-systematic, dealing with the importance of convenience for patient adherence, irrespective of disease and medicine type. The PubMed search was limited to reviews published between January 2009 and December 2014. Reference lists of included reviews were screened in order to identify other relevant literature. Results:The synthesis was based on 77 reviews with highly variable methodological quality. Few reviews included a systematic search; no reviews performed systematic meta-analyses. The scope and focus of reviews varied considerably; nearly all reviews focused on chronic disease, but within a large number of therapeutic areas. Most reviews that included a critical appraisal of primary original literature stressed a lack of well-defined definitions, interventions and endpoints. With this proviso, a general finding for orally administered medicines was that "regime complexity", including the number of daily doses and "units" per dosing, seemed to correlate negatively to adherence. For parenterally administered drugs, the importance of convenience was much less clear. Conclusions:The association between convenience and adherence has been discussed within many therapeutic areas, but only rarely examined using a stringent scientific-methodological approach. Data suggest that increasing regime complexity may lower adherence to orally administered drugs; this does not necessarily hold true for parenteral treatment. Given the overall low level of evidence, it remains uncertain whether increased convenience, often at a higher cost, should be a decisive factor when choosing between otherwise equal drug treatments. Solanum lycocarpum A. St.-Hil. (Solanaceae), popularly known as "fruit-of-wolf", is a hairy shrub or small much-branched tree of the Brazilian Cerrado. Plants belonging to the genus Solanum are known for their high concentration of alkaloids. Solasonine and solamargine are two of the major glycoalkaloids found in at least 100 Solanum species. Studies on solamargine activities have demonstrated its ability to inhibit human tumor cells proliferation. The present study aimed to investigate phytochemical composition and quimioprevention potential of a fruit extract of S. lycocarpum glycoalkaloid (SL) on colon and liver carcinogenesis in Wistar rats. Fruits of S. lycocarpum were collected in Ribeirão Preto -SP -Brazil. The dried powder from the fruits was submitted to acid-base extraction, suspended in distilled ethanol, filtered, concentrated under reduced pressure and lyophilized to furnish the glycoalkaloidic extract. Chromatographic analyses were performed in a HPLC equipment with a diode array detector. Animals were orally (gavage) treated with the extract at doses of 15, 30 and 60 mg/kg body weight/day. In the colon carcinogenesis protocol, two subcutaneous injection of 1,2-dimethylhydrazine (DMH; 40 mg/kg b.w.) were administered for two weeks; in the liver c...