Background

Cholesterol gallstones account for over 80% of gallstones, and the pathogenesis of gallstone formation involves genetic and environmental factors. However, data on the evolution of cholesterol gallstones with various densities are limited. This study aimed to determine the roles of microbiota and mucins on the formation of calcified cholesterol gallstones in patients with cholelithiasis.

Methods

Paired gallbladder tissues and bile specimens were obtained from cholelithiasis patients who were categorized into the isodense group and calcified group according to the density of gallstones. The relative abundance of microbiota in gallbladder tissues was detected. Immunohistochemistry and enzyme-linked immunosorbent assay were performed to detect the expression levels of MUC1, MUC2, MUC3a, MUC3b, MUC4, MUC5ac and MUC5b in gallbladder tissues and bile. The correlation of microbiota abundance with MUC4 expression was evaluated by linear regression.

Results

A total of 23 patients with gallbladder stones were included. The density of gallstones in the isodense group was significantly lower than that of the calcified group (34.20 ± 1.50 vs. 109.40 ± 3.84 HU, P < 0.0001). Compared to the isodense group, the calcified group showed a higher abundance of gram-positive bacteria at the fundus, in the body and neck of gallbladder tissues. The concentrations of MUC1, MUC2, MUC3a, MUC3b, MUC5ac and MUC5b in the epithelial cells of gallbladder tissues showed no difference between the two groups, while the concentrations of MUC4 were significantly higher in the calcified group than that in the isodense group at the fundus (15.49 ± 0.69 vs. 10.23 ± 0.54 ng/mL, P < 0.05), in the body (14.54 ± 0.94 vs. 11.87 ± 0.85 ng/mL, P < 0.05) as well as in the neck (14.77 ± 1.04 vs. 10.85 ± 0.72 ng/mL, P < 0.05) of gallbladder tissues. Moreover, the abundance of bacteria was positively correlated with the expression of MUC4 (r = 0.569, P < 0.05) in the calcified group.

Conclusions

This study showed the potential clinical relevance among biliary microbiota, mucins and calcified gallstones in patients with gallstones. Gram-positive microbiota and MUC4 may be positively associated with the calcification of cholesterol gallstones.

中文翻译：

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胆道微生物群和粘蛋白 4 影响胆固醇胆结石的钙化

背景

胆固醇性胆结石占胆结石的80%以上，胆结石形成的发病机制涉及遗传和环境因素。然而，关于不同密度胆固醇胆结石演变的数据是有限的。本研究旨在确定微生物群和粘蛋白在胆石症患者钙化胆固醇胆结石形成中的作用。

方法

根据胆结石的密度分为等密度组和钙化组的胆石症患者获得成对的胆囊组织和胆汁标本。检测到胆囊组织中微生物群的相对丰度。采用免疫组化和酶联免疫吸附法检测胆囊组织和胆汁中MUC1、MUC2、MUC3a、MUC3b、MUC4、MUC5ac和MUC5b的表达水平。通过线性回归评估微生物群丰度与 MUC4 表达的相关性。

结果

共纳入 23 名胆囊结石患者。等密度组胆结石密度显着低于钙化组（34.20±1.50 vs. 109.40±3.84 HU，P < 0.0001）。与等密度组相比，钙化组在胆囊组织的底部、身体和颈部显示出更高丰度的革兰氏阳性菌。两组胆囊组织上皮细胞中MUC1、MUC2、MUC3a、MUC3b、MUC5ac和MUC5b浓度无差异，而钙化组眼底MUC4浓度明显高于等密度组(15.49 ± 0.69 vs. 10.23 ± 0.54 ng/mL, P < 0.05), 在体内 (14.54 ± 0.94 vs. 11.87 ± 0.85 ng/mL, P< 0.05) 以及胆囊组织的颈部 (14.77 ± 1.04 vs. 10.85 ± 0.72 ng/mL, P < 0.05)。此外，钙化组细菌丰度与MUC4的表达呈正相关（r  =0.569，P <0.05）。

结论

该研究显示了胆结石患者胆道微生物群、粘蛋白和钙化胆结石之间的潜在临床相关性。革兰氏阳性菌群和 MUC4 可能与胆固醇胆结石的钙化呈正相关。