Antidiabetic Function of Lactobacillus fermentum MF423-Fermented Rice Bran and Its Effect on Gut Microbiota Structure in Type 2 Diabetic Mice

Abstract

Rice bran is an industrial byproduct that exerts several bioactivities despite its limited bioavailability. In this study, rice bran fermented with Lactobacillus fermentum MF423 (FLRB) had enhanced antidiabetic effects both in vitro and in vivo. FLRB could increase glucose consumption and decrease lipid accumulation in insulin resistant HepG2 cells. Eight weeks of FLRB treatment significantly reduced the levels of blood glucose and lipids and elevated antioxidant activity in type 2 diabetic mellitus (T2DM) mice. H&E staining revealed alleviation of overt lesions in the livers of FLRB-treated mice. Moreover, high-throughput sequencing showed notable variation in the composition of gut microbiota in FLRB-treated mice, especially for short-chain fatty acids (SCFAs)-producing bacteria such as Dubosiella and Lactobacillus. In conclusion, our results suggested that rice bran fermentation products can modulate the intestinal microbiota and improve T2DM-related biochemical abnormalities, so they can be applied as potential probiotics or dietary supplements.

Endurance exercise ameliorates Western diet–induced atherosclerosis through modulation of microbiota and its metabolites

“…Furthermore, lipocalin 2, an antimicrobial peptide expressed in the intestine, modulated obesity-associated and metabolic dysregulation through SCFA production regulated by Dubosiella and Angelakisella 43 . In addition, enriched Dubosiella in fermented rice bran–treated mice improved insulin sensitivity, antioxidative capacity, and lipid levels 44 . In another study, Faecalibaculum and its homology, Holdemanella biformis , demonstrated intestinal antitumorigenic effects through the production of SCFAs, which controlled the protein acetylation and tumor cell proliferation underlying calcineurin inhibition and NFATc3 activation 45 .…”

Effects of the Water Extract of Fermented Rice Bran on Liver Damage and Intestinal Injury in Aged Rats with High-Fat Diet Feeding

“…When supplemented with FRB, liver damage was alleviated as described by significantly lower NAFLD scores and liver IL-1β levels, and slightly lower levels of liver TNF-α and plasma TBARSs ( Figure 4 , Table 2 , Table 3 and Table 4 ). Likewise, Ai et al found that FRB could mitigate hepatic steatosis in mice with type 2 diabetes mellitus (T2DM) [ 35 ]. Lipid accumulation was also improved by FRB treatment in IR-HepG2 cells [ 35 ].…”

“…Likewise, Ai et al found that FRB could mitigate hepatic steatosis in mice with type 2 diabetes mellitus (T2DM) [ 35 ]. Lipid accumulation was also improved by FRB treatment in IR-HepG2 cells [ 35 ]. In a mouse model of obesity, it was reported that supplementation with FRB could decrease fatty depositions in liver tissues [ 36 ].…”

“…On the other hand, the species diversity increased after supplementation with 1% FRB ( Figure 9 C), and some dominant bacteria, including the probiotic Lactobacillaceae (family) and SCFA-producing Lachnospiraceae (family), were observed in the FRB-treated groups ( Figure 13 and Figure 14 ). A previous study revealed that FRB modulated the composition of the gut microbiota, especially enriching SCFA-producing bacteria such as Dubosiella and Lactobacillus and also increasing the SCFA levels in type 2 diabetic mice [ 35 ]. In a colitis mouse model, FRB enhanced SCFAs and tryptamine production, which promoted the tight junction barrier integrity [ 28 ].…”

“…Previous studies showed that 5% of FRB supplementation could attenuate metabolic syndrome [ 25 ] and obesity [ 35 ]. Muscle atrophy [ 26 ] and intestinal inflammatory disorders [ 28 ] were also prevented after 10% of RB fermented by A. kawachii and Lactobacillus sp.…”