Sericin consumption suppresses development and progression of colon tumorigenesis in 1,2-dimethylhydrazine-treated rats

Abstract

Colon cancer is one of the most common cancers in many regions of the world and is prevented by dietary interventions. This study aimed to examine the chemopreventive effect of silk protein, sericin, against 1,2-dimethylhydrazineinduced colon tumorigenesis in rats in comparison with control casein diet. The result showed that 5 out of 14 of casein fed rats developed colon tumors, whereas only 1 from 14 sericin fed rats exhibited tumors. Consumption of sericin prior to or during carcinogen exposure reduced the number of aberrant crypt foci. In addition to crypt number, crypt multiplicity was less progressive in sericin fed group. The sericin diet also exhibited anti-oxidant activity as evidenced by reduced lipid peroxidation in the colons. This finding suggests that consumption of sericin may reduce the progression of colon tumor development possibly by suppressing the initiation and promotion stages of colon tumorigenesis.

Extraction and antioxidant activity of sericin, a protein from silk

“…J. Food Technol., Campinas, v. 23, e2019058, 2020 | https://doi.org/10.1590/1981-6723.05819 7/14 2016; Napavichayanun et al, 2017;Deori et al, 2016;Sangwong et al, 2016;Kumar & Mandal (2017); Fan et al, 2010;Kaewkon et al, 2012;Zhaorigetu et al, 2001;Dash et al, 2008), and inhibits tyrosinase activity (Aramwit et al, 2010a;Kato et al, 1998;Thongsook & Tiyaboonchai, 2011;Puangphet et al, 2015;Wu et al, 2008;Manosroi et al, 2010). Table 3 provides an overview of studies supporting the sericin's antioxidant activity.…”

“…Because of this characteristic, the influence of sericin in colon cancer was investigated. Two studies performed in mice found a correlation between the ingestion of sericin and a positive effect in the incidence of colon tumors (Zhaorigetu et al, 2001;Kaewkon et al, 2012). Zhaorigetu et al (2001) histologically investigated the anti-tumoral function of sericin in colon cell and its relationship with the antioxidant activity of sericin.…”

“…Furthermore, they found a reduction of colonic lipid oxidation. The authors suggest that these findings might be due to a suppression activity exerted by sericin of the initiation and promotion stages of colon tumorigenesis (Kaewkon et al, 2012). The effect was also evaluated in human carcinogenic colon cells by an incubation of these cells with increasing concentrations of sericin varying in its molecular size as well.…”