A Specific Broccoli Sprout Preparation Reduces Chemically-Induced Colitis Via Gut Microbiota

Abstract

Objectives Sulforaphane is a bioactive metabolite with anti-inflammatory activity that is derived from glucosinolates, which are highly abundant in cruciferous vegetables including broccoli sprouts. There have been limited studies to investigate a whole foods approach to increase sulforaphane levels with therapeutic effect and reduce inflammation. In the current study, using a mouse model of inflammatory bowel disease, we aimed to investigate the ability of steamed broccoli sprouts to ameliorate colitis and the role of the microbiota in mediating any effects. Methods C57BL/6J male mice were fed base diet or 5% steamed broccoli sprout diet for 2 weeks prior to induction of colitis with 2–3% DSS (5–7 days) and kept on their respective diets until sacrifice. Body weight and disease activity index scores were recorded daily, and histological assessment was performed on H&E sections of colon. Urine, feces, blood, and GI tract tissues and intestinal content were collected for LC-MS/MS quantification of sulforaphane and glucoraphanin. The 16S rRNA sequencing was performed to analyze gut microbiome. Germ-free mice were fed base diet or 5% steamed broccoli sprout diet for 2 weeks followed by treatment with 5 days of DSS to determine the role of gut microbiota in mediating the anti-inflammatory effects of the steamed broccoli sprout diet. Results We observed that despite inactivation of the plant myrosinase enzyme responsible for the generation of sulforaphane via steaming, measurable levels of sulforaphane were detectable in the colon tissue and feces of mice after ingestion of steamed broccoli sprouts. In addition, this preparation of broccoli sprouts was also capable of reducing chemically-induced colitis. This protective effect was dependent on the presence of an intact gut microbiota, highlighting an important role for the microbiota in the metabolism of cruciferous vegetables to generate bioactive metabolites and promote their anti-inflammatory effects. Conclusions Altogether, these results suggest that the incorporation of a steamed broccoli sprouts diet is a viable dietary intervention to complement current medical therapies for patients with inflammatory bowel disease. Funding Sources This work was supported by USDA-NIFA-AFRI Foundational Program [Grant No. 2018–67,017-27,520].

Early life exposure to broccoli sprouts confers stronger protection against enterocolitis development in an immunological mouse model of inflammatory bowel disease

“…The sprouts were then crushed by mortar and pestle into a fine powder and mixed with purified 5LOD rodent diet powder and water to a concentration of 10% by weight. Our labs have assessed the effects of different diet preparations and the percentage of broccoli sprouts, and found that 5-10% broccoli sprouts by weight reliably produces consistent anti-inflammatory results (98). Diet pellets were formed using a silicone mold to ensure consistent sizing, and allowed to dry at room temperature for up to 48 hours in a chemical safety hood to facilitate moisture evaporation, and after drying were stored in ziploc bags in a −10°C freezer until future use.…”

Current Knowledge on the Preparation and Benefits of Cruciferous Vegetables as Relates to In Vitro, In Vivo, and Clinical Models of Inflammatory Bowel Disease

“…A steamed broccoli sprouts diet inhibited TNFɑ, IL1β, and IL6 and promoted bacteria richness such as Bacillota (formerly Firmicutes), Pseudomonadota (formerly Proteobacteria), Bacteroides, and Verrucomicrobiota against dysbiosis and IBD in DSS mice [ 48 ]. Microbial hydrolases and commensal microbiota promoted the beneficial effects of SFN [ 144 ] and SCFA production and decreased colonic ulceration [ 105 ]. Interestingly, eating broccoli sprouts early in life can improve microbiota richness.…”

Early life exposure to broccoli sprouts confers stronger protection against enterocolitis development in an immunological mouse model of inflammatory bowel disease

“…The control diet was 100% irradiated 5LOD diet irradiated 5LOD rodent diet powder (ScottPharma Inc., Marlborough, MA, #50795) mixed with ultra-pure water. The freeze-dried sprouts were crushed by mortar and pestle into a fine powder and mixed with the 5LOD powder and water to a concentration of 10% by weight to form the treatment diet, as that concentration reliably produces consistent anti-inflammatory results ( 48 ). Diet pellets were formed using a silicone mold to ensure consistent sizing, dried at room temperature for up to 48 h in a chemical safety hood to facilitate moisture evaporation, and after drying were stored in Ziploc bags in a −10℃ freezer until future use.…”

“…Purified GLR or SFN has been demonstrated to protect against chemical-induced ulcerative colitis in mice ( 38 , 47 – 49 ) and some pathogenic bacteria in the gut ( 50 , 51 ). However, purified SFN is unstable ( 52 , 53 ), and pure GLR induces extremely variable rates of conversion in humans ( 40 , 53 ).…”

“…However, purified SFN is unstable ( 52 , 53 ), and pure GLR induces extremely variable rates of conversion in humans ( 40 , 53 ). The conversion of GLR to SFN is achieved by plant-sourced enzymes when raw vegetables are chewed or chopped, as well as by microbially sourced enzymes in the gut ( 38 , 48 , 51 ). GLR is concentrated in broccoli sprouts, and our data have shown that a whole-food strategy using sprouts increases gut microbial richness, raises SFN levels in colon tissues and plasma, and reduces inflammation in chemically induced models of colitis ( 38 , 47 , 48 ).…”