Association between nonalcoholic fatty liver disease and increased glucose-to-albumin ratio in adults without diabetes

Background

Nonalcoholic fatty liver disease (NAFLD) affects approximately 30% of individuals globally. Both serum glucose and albumin were demonstrated to be potential markers for the development of NAFLD. We hypothesized that the risk of NAFLD may be proportional to the glucose-to-albumin ratio (GAR).

Methods

Based on information from the National Health and Nutrition Examination Survey (NHANES) 1999-2018, it was determined that GAR was associated with an increased risk of NAFLD and liver fibrosis utilizing weighted multivariable logistic regression. Participants with a fatty liver index (FLI) over 60 were identified with NAFLD, and those with an NAFLD fibrosis score (NFS) >0.676 with evidence of NAFLD were labeled with advanced hepatic fibrosis (AHF). The liver biopsy was utilized to verify the relationship between GAR and FLD in our center cohort. Mendelian randomization analysis investigated the genetic relationship between GAR and NAFLD.

Results

Of 15,534 eligible participants, 36.4% of participants were identified as NAFLD without AHF. GAR was positively correlated with the probability of NAFLD following full adjustment for possible variables (OR = 1.53, 95% CI: 1.39-1.67). It was confirmed that patients with NAFLD and AHF had an inferior prognosis. The relationship between GAR and NFS was favorable (R = 0.46, P< 0.0001), and NAFLD patients with a higher GAR tended to develop poor survival. In our center cohort, the association between GAR and NAFLD was verified.

Conclusion

Among participants without diabetes, greater GAR was linked to higher risks of NAFLD. In addition, NAFLD patients with higher GAR tended to develop liver fibrosis and adverse outcomes.

Mitochondrial miR-23b-5p is a new biomarker of warm ischaemic injury in donor livers and a candidate for graft evaluation: experimental studies

BACKGROUND AND AIMS

Warm ischaemic injury (WII) stems from incorrect energy metabolism and is the main cause of graft dysfunction. Mitochondria, as the centre of cellular metabolic activities, may be the key in identifying accurate indicators for evaluating the quality of grafts. Our research focuses on the screening, clinical application, and mechanism of the optimal WII mitochondrion biomarker.

APPROACH AND RESULTS

Using a 100% hepatic warm ischaemia mouse model, without reperfusion, transmission electron microscopy demonstrated evident morphological changes of hepatic mitochondria at 15 min of ischaemia. However, all 13 mt-mRNAs could not display continuously upregulated consistency at 0-15-30-60 min during WII. High-throughput analysis of miRNA expression in both purified mitochondria and liver tissues suggested miR-23b-5p was a potential mitochondrial microRNA (mitomiR) biomarker with high sensitivity and 0-15-30-60 min change consistency. Fluorescence in-situ hybridization and reverse transcription quantitative polymerase chain reaction (RT-qPCR) further confirmed the results. Through overexpression and inhibition, the functionality of this mitomiR during WII was identified as a protective regulator in vitro and then verified in Dicer1 fl/fl Alb Cre mice by downregulation of other miRNAs and supplementation of mature mitomiR-23b-5p. Dual-luciferase reporter assay and the Seahorse XF analyzer determined that mitomiR-23b-5p reduced mitochondrial respiratory function by silencing mt-RNR2 (16S). Clinically, mitomiR-23b-5p was positively correlated with serum alanine aminotransferase levels 3 days after the operation ( P =0.032), and the C-statistic for 90-day graft survival rate was 0.698.

CONCLUSIONS

MitomiR-23b-5p plays a protective regulatory role and implements a special mitochondrial regulation mechanism not yet reported in WII. These clinical results further support the experimental result that the expression of MitomiR-23b-5p is closely related to the prognosis of clinical liver transplantation patients. This is a promising new biomarker for WII evaluation of donor livers.

Single-cell RNA-seq revealing the immune features of donor liver during liver transplantation

Immune cells, including T and B cells, are key factors in the success of liver transplantation. And the repertoire of T cells and B cells plays an essential function in mechanism of the immune response associated with organ transplantation. An exploration of their expression and distribution in donor organs could contribute to a better understanding of the altered immune microenvironment in grafts. In this study, using single-cell 5' RNA sequence and single-cell T cell receptor (TCR)/B cell receptor (BCR) repertoire sequence, we profiled immune cells and TCR/BCR repertoire in three pairs of donor livers pre- and post-transplantation. By annotating different immune cell types, we investigated the functional properties of monocytes/Kupffer cells, T cells and B cells in grafts. Bioinformatic characterization of differentially expressed genes (DEGs) between the transcriptomes of these cell subclusters were performed to explore the role of immune cells in inflammatory response or rejection. In addition, we also observed shifts in TCR/BCR repertoire after transplantation. In conclusion, we profiled the immune cell transcriptomics and TCR/BCR immune repertoire of liver grafts during transplantation, which may offer novel strategies for monitoring recipient immune function and treatment of rejection after liver transplantation.