Role of the Free Radicals in Mechanisms of Gallstone Formation: An EPR Study

Insight into the mechanism of gallstone disease by proteomic and metaproteomic characterization of human bile

Introduction

Cholesterol gallstone disease is a prevalent condition that has a significant economic impact. However, the role of the bile microbiome in its development and the host's responses to it remain poorly understood.

Methods

In this study, we conducted a comprehensive analysis of microbial and human bile proteins in 40 individuals with either gallstone disease or gallbladder polyps. We employed a combined proteomic and metaproteomic approach, as well as meta-taxonomic analysis, functional pathway enrichment, and Western blot analyses.

Results

Our metaproteomic analysis, utilizing the lowest common ancestor algorithm, identified 158 microbial taxa in the bile samples. We discovered microbial taxa that may contribute to gallstone formation, including β-glucuronidase-producing bacteria such as Streptococcus, Staphylococcus, and Clostridium, as well as those involved in biofilm formation like Helicobacter, Cyanobacteria, Pseudomonas, Escherichia coli, and Clostridium. Furthermore, we identified 2,749 human proteins and 87 microbial proteins with a protein false discovery rate (FDR) of 1% and at least 2 distinct peptides. Among these proteins, we found microbial proteins crucial to biofilm formation, such as QDR3, ompA, ndk, pstS, nanA, pfIB, and dnaK. Notably, QDR3 showed a gradual upregulation from chronic to acute cholesterol gallstone disease when compared to polyp samples. Additionally, we discovered other microbial proteins that enhance bacterial virulence and gallstone formation by counteracting host oxidative stress, including sodB, katG, rbr, htrA, and ahpC. We also identified microbial proteins like lepA, rtxA, pckA, tuf, and tpiA that are linked to bacterial virulence and potential gallstone formation, with lepA being upregulated in gallstone bile compared to polyp bile. Furthermore, our analysis of the host proteome in gallstone bile revealed enhanced inflammatory molecular profiles, including innate immune molecules against microbial infections. Gallstone bile exhibited overrepresented pathways related to blood coagulation, folate metabolism, and the IL-17 pathway. However, we observed suppressed metabolic activities, particularly catabolic metabolism and transport activities, in gallstone bile compared to polyp bile. Notably, acute cholelithiasis bile demonstrated significantly impaired metabolic activities compared to chronic cholelithiasis bile.

Conclusion

Our study provides a comprehensive metaproteomic analysis of bile samples related to gallstone disease, offering new insights into the microbiome-host interaction and gallstone formation mechanism.

Efficacy of Thiol Disulfide Homeostasis and Ischemia Modified Albumin Values in Estimating the Degree of Difficulty for Laparoscopic Cholecystectomy

Aim:

The aim of this study was to investigate the efficacy of thiol disulfide homeostasis and Ischemia Modified Albumin (IMA) values in predicting the technical difficulties that might be encountered during laparoscopic cholecystectomy.

Materials and Methods:

The study included 65 patients who underwent laparoscopic cholecystectomy due to cholelithiasis at the General Surgery Clinic of Ankara Numune Training and Research Hospital. All patients’ demographic data, previous history of cholecystitis, a history of chronic illness, preoperative white blood count (WBC), liver function tests (AST, ALT), amylase and lipase levels, intra-operative adhesion score, the ultrasonographic appearance of gall bladder, duration of hospital stay, duration of operation, thiol disulfide and IMA values were evaluated.

Results:

Native thiol and total thiol averages were higher in patients without a history of cholecystitis, and on the other hand, disulfide, disulfide/native thiol rate, disulfide/total thiol rate, native thiol/total thiol rate and IMA averages were higher in patients with a history of cholecystitis. While there was a statistically significant negative correlation between native and total thiol values and age, duration of surgery and duration of hospital stay; IMA, disulfide, disulfide/Total thiol, Native/Total thiol and disulfide/Native thiol rates were higher in older patients with a longer duration of surgery and hospital stay. In addition, preoperative IMA, disulfide, disulfide/Total thiol, Native/Total thiol and disulfide/Native thiol were observed to increase as the degree of intraoperative pericholecystic adhesion increased.

Conclusion:

We believe that the evaluation of thiol disulfide homeostasis and IMA parameters prior to laparoscopic cholecystectomy can be used as an effective method for predicting intraoperative difficulties.