No abstract

DJB preferentially increases serum taurine-conjugated BAs, probably because of more BA reabsorption in the terminal ileum. The gut microbiota is altered with more Firmicutes and Proteobacteria and less Bacteroidetes.

The preferentially elevated serum taurine-conjugated BAs were similar after different bariatric surgeries, and the enhanced conjugation of BAs in the liver might account for the changed serum BAs profiles.

DJB and SG ameliorated cardiac dysfunction by inhibiting PERK-mediated pathway. And no difference was observed on the effects of DJB and SG on ER stress-dependent myocardium damage in diabetic rats.

No abstract

Bile acids (BAs), which are synthesized in the liver and cycled in the enterohepatic circulation, have been recognized as signaling molecules by activating their receptors in the intestine and liver. Serum taurine-conjugated BAs have been shown to be elevated after bariatric surgeries although the postoperative BA profiles within the enterohepatic circulation have not been investigated. Clarification of these profiles could help explain the mechanisms by which bariatric surgery leads to BA profile alterations and subsequent metabolic effects. We performed duodenal-jejunal bypass (DJB), sleeve gastrectomy (SG), and sham procedures in an obese diabetic rat model induced by high-fat diet and streptozotocin. The weight loss and antidiabetic effects were evaluated postsurgery. BA profiles in the systemic serum and within the enterohepatic circulation were analyzed, together with the expression of related BA transporters and enzymes at week 12 after surgery. Compared with sham, SG induced sustained weight loss, and both DJB and SG significantly improved glucose tolerance and insulin sensitivity with enhanced glucagon-like peptide 1 secretion. Similar to changes in the serum, BAs, especially taurine-conjugated species, were also elevated in the enterohepatic circulation (bile and portal vein) after DJB and SG. In addition, the expression of key BA transporters and conjugational enzymes was elevated postoperatively, whereas the enzymes responsible for BA synthesis were decreased. In conclusion, DJB and SG elevated BA levels in the systemic serum and enterohepatic circulation, especially taurine-conjugated species, which likely indicates increased ileal reabsorption and hepatic conjugation rather than synthesis. NEW & NOTEWORTHY Bile acids (BAs) have been implicated as potential mediators of the weight-independent effects of bariatric surgery. For the first time, we discovered that duodenal-jejunal bypass and sleeve gastrectomy elevated BAs, particularly the taurine-conjugated species in the enterohepatic circulation, likely through the promotion of ileal reabsorption and hepatic conjugation rather than BA synthesis. These findings will improve our understanding of BA metabolism after bariatric surgery and their subsequent metabolic effects.

BackgroundThe aim of this study was to investigate the association between plasma levels of homocysteine and the occurrence and progression of rectal cancer.Material/MethodsThe 320 study participants included healthy controls (n=80). and patients with rectal tumors (n=240), including 155 patients with rectal cancer, Stage I (n=32), Stage II (n=38), Stage III (n=50), and Stage IV (n=35), and patients with low-risk rectal adenomas (n=31), and high-risk rectal adenomas (n=54). All study participants had fasting blood samples taken, and plasma levels of homocysteine and carcinoembryonic antigen (CEA) were measured and compared. Receiver operating characteristic (ROC) curves were prepared to determine whether single, combined, or series levels of the two markers were diagnostic.ResultsA significantly increasing trend in the plasma levels of homocysteine from the healthy controls, to the individuals with low-risk rectal adenoma, high-risk rectal adenoma, and Stage I–IV rectal cancer were found. There were no statistically significant differences in the area under the curve (AUC) between the two single factors of plasma homocysteine and CEA. The AUC showed that the use of combined or parallel measurement of plasma CEA and homocysteine had the greatest diagnostic associations.ConclusionsPlasma levels of homocysteine were significantly associated with occurrence and progression of rectal cancer. The combined use of measurement of plasma homocysteine and CEA levels might have the potential to increase the diagnostic efficiency of screening for early rectal cancer.

The percentage of 12α-hydroxylated bile acids was reduced after SG, which was relevant with the inhibition of CYP8B1 and overexpression of MAFG. These outcomes may play an important role in the improvement of insulin sensitivity following SG.