Cholecystectomy - a potential selection bias in studies assessing the metabolic effects of bariatric surgeries

Review on chronic metabolic diseases surrounding bile acids and gut microbiota: What we have explored so far

Bile acid, the final product of cholesterol breakdown, functions as a complex regulator and signaling factor in human metabolism. Chronic metabolic diseases pose significant medical challenges. Growing research underscores bile acids' capacity to enhance metabolism via diverse pathways, regulating disorders and offering treatment potential. Numerous bile-acid-triggered pathways have become treatment targets. This review outlines bile acid synthesis, its role as a signal in chronic metabolic diseases, and highlights its interaction with gut microbiota in different metabolic conditions. Exploring host-bacteria-bile acid links emerges as a valuable future research direction with clinical implications.

A systematic review on omics data (metagenomics, metatranscriptomics, and metabolomics) in the role of microbiome in gallbladder disease

Microbiotas are the range of microorganisms (mainly bacteria and fungi) colonizing multicellular, macroscopic organisms. They are crucial for several metabolic functions affecting the health of the host. However, difficulties hamper the investigation of microbiota composition in cultivating microorganisms in standard growth media. For this reason, our knowledge of microbiota can benefit from the analysis of microbial macromolecules (DNA, transcripts, proteins, or by-products) present in various samples collected from the host. Various omics technologies are used to obtain different data. Metagenomics provides a taxonomical profile of the sample. It can also be used to obtain potential functional information. At the same time, metatranscriptomics can characterize members of a microbiome responsible for specific functions and elucidate genes that drive the microbiotas relationship with its host. Thus, while microbiota refers to microorganisms living in a determined environment (taxonomy of microorganisms identified), microbiome refers to the microorganisms and their genes living in a determined environment and, of course, metagenomics focuses on the genes and collective functions of identified microorganisms. Metabolomics completes this framework by determining the metabolite fluxes and the products released into the environment. The gallbladder is a sac localized under the liver in the human body and is difficult to access for bile and tissue sampling. It concentrates the bile produced in the hepatocytes, which drains into bile canaliculi. Bile promotes fat digestion and is released from the gallbladder into the upper small intestine in response to food. Considered sterile originally, recent data indicate that bile microbiota is associated with the biliary tract’s inflammation and carcinogenesis. The sample size is relevant for omic studies of rare diseases, such as gallbladder carcinoma. Although in its infancy, the study of the biliary microbiota has begun taking advantage of several omics strategies, mainly based on metagenomics, metabolomics, and mouse models. Here, we show that omics analyses from the literature may provide a more comprehensive image of the biliary microbiota. We review studies performed in this environmental niche and focus on network-based approaches for integrative studies.

Cholecystectomy Concomitant with Bariatric Surgery: Safety and Metabolic Effects

BACKGROUND

Obesity and fast weight loss in the postoperative period of bariatric surgery increase significantly the risk of cholelithiasis. Moreover, emerging evidence has pointed out the role of bile acids as possible metabolism and weight loss enhancers. This study aims to analyze the influence of cholecystectomy (CL) concomitant with bariatric surgery on weight loss, metabolic repercussions, and postoperative morbidity.

STUDY DESIGN

Retrospective cohort study. A total of 363 medical records were analyzed between 2002 and 2017, with 255 patients divided into four groups: with concomitant CL: sleeve gastrectomy (SG + CL group) and Roux-en-Y gastric bypass (GB + CL group); without concomitant CL: sleeve gastrectomy (SG group) and RYGB (GB group).

RESULTS

CL concomitant with bariatric surgery is not related to worse long-term metabolic outcomes when compared to isolated bariatric surgery. In the postoperative follow-up of the isolated bariatric surgeries, 18 (16.5%) patients underwent cholecystectomy. There was no statistical difference between the groups regarding post-surgical complications.

CONCLUSION

CL did not lead to worse metabolic outcomes and was also not related to a higher incidence of postoperative complications. Cholelithiasis and cholecystitis are important concerns in the postoperative period of bariatric surgery and a careful evaluation of the concomitant procedure should be performed.

Cholecystectomy as a risk factor for metabolic dysfunction-associated fatty liver disease: unveiling the metabolic and chronobiologic clues behind the bile acid enterohepatic circulation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is highly prevalent worldwide. Recent clinical and experimental studies have addressed the association between cholecystectomy and MAFLD, confirming that cholecystectomy is an independent risk factor for MAFLD. In this review, we describe the epidemiologic evidence that links cholecystectomy to MAFLD, and discuss the possible mechanisms behind these connections, in order to unveil the metabolic and chronobiologic signals conveyed by the waves of the bile acid enterohepatic circulation.