Introduction

Lipopolysaccharide (LPS) causes lesions of the epithelial barrier, which allows translocation of pathogens from the intestinal lumen to the host’s circulation. Hydrogen sulfide (H₂S) regulates multiple physiological and pathological processes in colonic epithelial tissue, and CBS-H₂S axis involved in multiple gastrointestinal disorder. However, the mechanism underlying the effect of the CBS-H₂S axis on the intestinal and systemic inflammation in colitis remains to be illustrated.

Objectives

To investigate the effect of CBS-H₂S axis on the intestinal and systematic inflammation related injuries in LPS induced colitis and the underlying mechanisms.

Methods

Wild type and CBS^−/+ mice were used to evaluate the effect of endogenous and exogenous H₂S on LPS-induced colitis in vivo. Cytokine quantitative antibody array, western blot and real-time PCR were applied to detect the key cytokines in the mechanism of action. Biotin switch of S-sulfhydration, CRISPR/Cas9 mediated knockout, immunofluorescence and ActD chase assay were used in the in vitro experiment to further clarify the molecular mechanisms.

Results

H₂S significantly alleviated the symptoms of LPS-induced colitis in vivo and attenuated the increase of COX-2 expression. The sulfhydrated HuR increased when CBS express normally or GYY4137 was administered. While after knocking kown CBS, the expression of COX-2 in mice colon increased significantly, and the sulfhydration level of HuR decreased. The results in vitro illustrated that HuR can increase the stability of COX-2 mRNA, and the decrease of COX-2 were due to increased sulfhydration of HuR rather than the reduction of total HuR levels.

Conclusion

These results indicated that CBS-H₂S axis played an important role in protecting intestinal barrier function in colitis. CBS-H₂S axis increases the sulfhydration level of HuR, by which reduces the binding of HuR with COX-2 mRNA and inhibited the expression of COX-2.

中文翻译：

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CBS-H2S 轴通过在结肠炎中硫化人抗原 R 来抑制 COX-2，从而保持肠道屏障功能

介绍

脂多糖 (LPS) 会导致上皮屏障损伤，从而使病原体从肠腔转移到宿主的循环系统中。硫化氢(H ₂ S)调节结肠上皮组织的多种生理和病理过程，CBS-H ₂ S轴参与多种胃肠道疾病。然而，CBS-H ₂ S 轴对结肠炎中肠道和全身炎症影响的潜在机制仍有待阐明。

目标

探讨CBS-H ₂ S轴对LPS诱导的结肠炎肠道和全身炎症相关损伤的影响及其机制。

方法

野生型和CBS ^-/+小鼠用于评估内源性和外源性H ₂ S对体内LPS诱导的结肠炎的影响。应用细胞因子定量抗体芯片、western blot和real-time PCR检测作用机制中的关键细胞因子。S-硫化生物素开关、CRISPR/Cas9介导的基因敲除、免疫荧光和ActD追踪分析用于体外实验，进一步阐明分子机制。

结果

H _{2 S 显着减轻}体内LPS 诱导的结肠炎症状并减弱 COX-2 表达的增加。当 CBS 正常表达或施用 GYY4137 时，硫化 HuR 增加。而敲除已知CBS后，小鼠结肠COX-2表达显着增加，HuR硫化水平降低。体外结果表明，HuR 可以增加 COX-2 mRNA 的稳定性，而 COX-2 的降低是由于 HuR 的硫化作用增加，而不是总 HuR 水平的降低。

结论

这些结果表明CBS-H ₂ S轴在保护结肠炎的肠屏障功能中起重要作用。CBS-H ₂ S轴增加HuR的硫化水平，从而降低HuR与COX-2 mRNA的结合，抑制COX-2的表达。