Protective effect ofLactobacillus rhamnosus231 against N-Methyl-N′-nitro-N-nitrosoguanidine in animal model

Abstract

The protective effect of Lactobacillus rhamnosus 231 (Lr 231) against potent carcinogen N-Methyl-N'-Nitro-N-Nitrosoguanidine (MNNG) in the rat model is studied. Daily feeding with Lr 231 improved the body weight of male Wistar rats compared with control groups. Fecal azoreductase (p < 0.001) and nitroreductase (p < 0.01) enzyme activity decreased significantly in Lr 231 group in comparison with control groups that received only phosphate buffer or MNNG. Oral administration of MNNG led to a significant increase in Glutathione transferase (GST) while Glutathione reductase (GSH) showed decreased activity. Conversely, feeding Lr 231 showed significantly increased GSH and decreased GST activity in comparison to the MNNG group, emphasizing the protection provided by Lr 231 against MNNG. Histopathological analysis of liver, spleen and colon showed decreased signs of inflammation in the Lr 231 group. The present study highlights that inclusion of active Lr 231 in regular diets could be used to prevent MNNG induced colon carcinoma.

Differential modulation of innate immunity in vitro by probiotic strains of Lactobacillus gasseri

“…In contrast, the increased intracellular GSH concentration accompanied by the increase in GSHtot export from the DCs without any measurable raise of intracellular GSSG concentration indicates the ability of DCs to respond to L. gasseri -induced oxidative stress by increasing GSH synthesis. These results, along with the results showing the improvement of GST and NQO1 activities in DCs directly exposed to L. gasseri strains or to conditioned supernatants from MODE-K cells, along with in vivo studies, further support the ability of bacterial strains to activate the Nrf-2 pathway [8,9]. …”

“…During oxidative stress, following detachment from a cytosolic inhibitor (Keap1), Nrf2 translocates to the nucleus and leads to transcription of antioxidant and detoxifying enzymes involved in detoxification and chemoprevention such as glutathione S-transferases (GSTs), NAD(P)H:quinone oxidoreductase (NQO1) and gamma-glutamylcysteine ligase (γGCL), which is the rate-limiting enzyme for glutathione (GSH) synthesis [5]. Bacteria-induced ROS generation greatly influences eukaryotic signaling pathways including those inducing Nrf2 [6,7], and improved Nrf2-mediated protection is associated with beneficial effects elicited by probiotic intake [8,9]. …”

Potential of probiotics, prebiotics and synbiotics for management of colorectal cancer

“…Glutathione reductase activity was increased while glutathione S-transferase activity was reduced in the Lr 231-fed group. 64 This was also evident in the histopathological sections of Lr 231-fed group. 64 Therefore, Lr 231 supplementation protected the animals from MNNG-induced inflammation.…”

“…64 This was also evident in the histopathological sections of Lr 231-fed group. 64 Therefore, Lr 231 supplementation protected the animals from MNNG-induced inflammation. Safety of this strain is proved in mouse model.…”

“…63 Administration of viable Lr 231 protected rats from MNNG-induced colon inflammation. 64 Levels of azoreductase, nitroreductase activities in the feces were reduced. Glutathione reductase activity was increased while glutathione S-transferase activity was reduced in the Lr 231-fed group.…”