Dietary broccoli improves markers associated with glucose and lipid metabolism through modulation of gut microbiota in mice

OBJECTIVE

Broccoli is a "functional food" that contains bioactive compounds and phytochemicals that have beneficial health-promoting effects. This study aimed at investigating the effects of broccoli consumption on lipid and glucose metabolism and gut microbiota.

METHODS

Male C57BL/6J mice (7-8 wk old) were fed ad libitum with a normal diet supplemented with or without 10% (w/w) broccoli florets or broccoli stalks. Oral glucose tolerance tests were performed at week 15. After 17 wk, blood and tissues were collected. Serum parameters, histology, gene and protein expression, and intestinal microbiota composition were evaluated.

RESULTS

Stalk supplementation led to reductions in fasting glucose levels, serum insulin, and the homeostasis model assessment-insulin resistance (HOMA-IR) index. Liver enzymes improved in both experimental groups, and broccoli florets decreased total triacylglycerols. The stalks group had elevated fatty acid oxidation-related genes and proteins (AMPK, PPARα, and CPT1). Diverse microbiota populations were observed in both broccoli groups. Broccoli stalks were found to be richer in Akkermansia muciniphila, while broccoli florets reduced Mucispirillum schaedleri abundance and increased bacterial richness.

CONCLUSIONS

Long-term whole broccoli supplementation decreased inflammation, improved lipid parameters and insulin sensitivity, and altered the gut microbiome in mice. Our data provide new information regarding the potential benefits of broccoli stalks in metabolic parameters.

Evaluation of hypoglycemic and hypolipidemic activity of methanol extract of Brassica oleracea

AIM

The hypoglycemic and hypolipidemic effects of the methanol extract of Brassica oleracea var. capitata (MEB) was evaluated in alloxan-induced diabetic rabbits.

METHOD

The study was conducted on twenty-eight healthy white rabbits of either sex. All animals were equally divided into four groups. After confirmation of hyperglycemia, the animals of the treated and standard groups were administered MEB (500 mg·kg(-1)) and glibenclamide (10 mg·kg(-1)), respectively for 15 and 30 days. The animals of the normal and diabetic controls received normal saline 1 mL/day equivalent to the volume of doses given to the test and standard animals. Biochemical tests were performed at the end of dosing, i.e. the 16(th) and 31(st) days.

RESULTS

The MEB revealed a decrease of 106.6 mg·dL(-1) in fasting blood glucose as compared to diabetic control, which was almost comparable to glibenclamide; both of these changes were highly significant. The decrease in total cholesterol and low density lipoprotein was 94.3 and 96.5 mg·dL(-1), respectively, whereas the high-density lipoprotein was increased by 26.7 mg·dL(-1), as compared to diabetic control. All of the changes in lipid profile were statistically significant.

CONCLUSION

These results suggest the potential of MEB as a hypoglycemic and hypolipidemic agent.

In Vitroandin VivoAntioxidant Activity of Alfalfa (Medicago sativaL.) on Carbon Tetrachloride Intoxicated Rats

The present study was conducted to determine whether lyophilized aqueous extract of alfalfa, or Medicago sativa L. could exert antioxidant activity against carbon tetrachloride-induced oxidative stress and liver injury in rats. The hepatoprotective activity of alfalfa extract was determined by assessing the levels of serum transaminases, ALP, bilirubin and lipid profile. Further, the effect of the test substance on malondialdehyde (MDA), an end product of lipid peroxidation; antioxidant liver enzyme non-protein sulfhydryl (NP-SH); and total protein (TP) were also studied. Serum transaminase, ALP, bilirubin level, lipid profile and liver MDA were significantly elevated and the antioxidant status in liver NP-SH and TP contents were declined in animals treated with CCl4alone. Pretreatment with alfalfa and silymarin for three weeks prior to the administration of CCl4significantly prevented the increase in the serum levels of hepatic marker, LDL, VLDL levels enzymes and reduced oxidative stress indicated by elevated NP-SH and TP concentration. The histopathological examination of the livers also showed that the alfalfa extract reduced the incidence of liver lesions induced by CCl4. The in vitro antioxidant assessment of alfalfa extract on DPPH and carotene-linoleic assays demonstrated a moderate antioxidant potential. Results suggest that the alfalfa extract possesses hepatoprotective and antioxidative stress properties possibly through its antioxidant phytochemical constituents and substantiates its use in various liver disorders as a hepatoprotector.