Low-dose steroid pretreatment ameliorates the transient impairment of liver regeneration

The integrated analysis of gut microbiota and metabolome revealed steroid hormone biosynthesis is a critical pathway in liver regeneration after 2/3 partial hepatectomy

Introduction: The liver is the only organ capable of full regeneration in mammals. However, the exact mechanism of gut microbiota and metabolites derived from them relating to liver regeneration has not been fully elucidated. Methods: To demonstrate how the gut-liver axis contributes to liver regeneration, using an LC-QTOF/MS-based metabolomics technique, we examine the gut microbiota-derived metabolites in the gut content of C57BL/6J mice at various points after 2/3 partial hepatectomy (PHx). Compound identification, multivariate/univariate data analysis and pathway analysis were performed subsequently. The diversity of the bacterial communities in the gastrointestinal content was measured using 16S rRNA gene sequencing. Then, the integration analysis of gut microbiota and metabolome was performed. Results: After 2/3 PHx, the residual liver proliferated quickly in the first 3 days and had about 90% of its initial weight by the seventh day. The results of PLS-DA showed that a significant metabolic shift occurred at 6 h and 36 h after 2/3 PHx that was reversed at the late phase of liver regeneration. The α and β-diversity of the gut microbiota significantly changed at the early stage of liver regeneration. Specifically, Escherichia Shigella, Lactobacillus, Akkermansia, and Muribaculaceae were the bacteria that changed the most considerably during liver regeneration. Further pathway analysis found the most influenced co-metabolized pathways between the host and gut bacteria including glycolysis, the TCA cycle, arginine metabolism, glutathione metabolism, tryptophan metabolism, and purine and pyrimidine metabolism. Specifically, steroid hormone biosynthesis is the most significant pathway of the host during liver regeneration. Discussion: These findings revealed that during liver regeneration, there was a broad modification of gut microbiota and systemic metabolism and they were strongly correlated. Targeting specific gut bacterial strains, especially increasing the abundance of Akkermansia and decreasing the abundance of Enterobacteriaceae, may be a promising beneficial strategy to modulate systemic metabolism such as amino acid and nucleotide metabolism and promote liver regeneration.

Preoperative single-dose methylprednisolone versus placebo after major liver resection in adults: protocol for a randomised controlled trial

INTRODUCTION

Although randomised controlled trials have demonstrated that preoperative glucocorticoids may improve postoperative surrogate outcomes among patients undergoing major liver resection, evidence supporting improved patient-important outcomes is lacking. This superiority trial aims to evaluate the effect of administration of a bolus of the glucocorticoid methylprednisolone versus placebo during induction of anaesthesia on postoperative morbidity among adults undergoing elective major liver resection.

METHODS AND ANALYSIS

This will be a randomised, dual-arm, parallel-group, superiority trial. All consecutive adults presenting to a large Canadian tertiary care hospital who consent to undergo major liver resection will be included. Patients aged <18 years and those currently receiving systemic corticosteroid therapy will be excluded. We will randomly allocate participants to a preoperative 500 mg intravenous bolus of methylprednisolone versus placebo. Surgical team members and outcome assessors will be blinded to treatment allocation status. The primary outcome measure will be postoperative complications. Secondary outcome measures will include mortality, the incidence of several specific postoperative complications, and blood levels of select proinflammatory cytokines, acute-phase proteins, and laboratory liver enzymes or function tests on postoperative days 0, 1, 2 and 5. The incidence of postoperative complications and mortality will be compared using Fisher's exact test, while the above laboratory measures will be compared using mixed-effects models with a subject-specific random intercept.

ETHICS AND DISSEMINATION

This trial will evaluate the protective effect of a single preoperative dose of methylprednisolone on the hazard of postoperative complications. A report releasing study results will be submitted for publication in an appropriate journal, approximately 3 months after finishing the data collection.

TRIAL REGISTRATION NUMBER

NCT01997658; Pre-results.