Galacto-oligosaccharides derived from lactulose protects against colorectal cancer development in a animal model

Resumen del trabajo presentado al IX Workshop on Probiotics, Prebiotics of the Spanish Society of Probiotics and Prebiotics (Sociedad Española de Probióticos y Prebióticos, SEPyP), celebrado en Zaragoza (España) del 15 al 16 de febrero de 2018.[Introduction] Colorectal cancer has become one of the leading causes of cancer-related mortality worldwide; consequently, much attention has been focused on preventive and therapeutic strategies. In this sense, prebiotics have been reported as potential anti-inflammatory and anti-carcinogenic agents within the gastrointestinal tract. In this work, we have investigated the protective effect of novel galacto-oligosacharides derived from lactulose (GOS-Lu). These prebiotics have shown strong bifidogenic properties in vivo (Clemente et al., 2011; Hernández-Hernández et al., 2012).[Objectives] GOS-Lu has been tested here as potential antitumor preventive prebiotic, in a rat model developed with azoxymethane (AOM) as chemical inducer of colorectal cancer.[Methods] Male Fisher 344 rats were randomly assigned to two groups (n=10 per group, including 2 rats lacking colorectal cancer AOM induction): one cohort (negative control) with drinking water, and experimental cohort with 10% GOS-Lu (w/v) added to drinking water. Eight animals in each cohort received two doses of AOM (10 mg/kg) plus two treatments with DSS (3% and 2%). After 17 weeks, animals were sacrificed and colon tissues analyzed for number of tumors and tumor mucosa affected area.[Results] Anatomical studies showed that caecum weight was enlarged a 35.2% on average (p<0.05) in experimental animals fed GOS-Lu. The number of colon tumors was decreased 57.5% on average (p<0.05) in prebiotic-fed animals. In addition, the tumor affected area in colon mucosa was reduced a 50.5% on average (p