Liver transplantation in patients with liver failure: Twenty years of experience from China

Liver-secreted FGF21 induces sarcopenia by inhibiting satellite cell myogenesis via klotho beta in decompensated cirrhosis

BACKGROUND & AIMS

Sarcopenia, a prevalent condition, significantly impacts the prognosis of patients with decompensated cirrhosis (DC). Serum fibroblast growth factor 21 (FGF21) levels are significantly higher in DC patients with sarcopenia. Satellite cells (SCs) play a role in aging- and cancer-induced sarcopenia. Here, we investigated the roles of FGF21 and SCs in DC-related sarcopenia as well as the underlying mechanisms.

METHODS

We developed two DC mouse models and performed in vivo and in vitro experiments. Klotho beta (KLB) knockout mice in SCs were constructed to investigate the role of KLB downstream of FGF21. In addition, biological samples were collected from patients with DC and control patients to validate the results.

RESULTS

Muscle wasting and impaired SC myogenesis were observed in the DC mouse model and patients with DC. Elevated circulating levels of liver-derived FGF21 were observed, which were significantly negatively correlated with skeletal muscle mass/skeletal muscle index. Liver-secreted FGF21 induces SC dysfunction, contributing to sarcopenia. Mechanistically, FGF21 in the DC state exhibits enhanced interactions with KLB on SC surfaces, leading to downstream phosphatase and tensin homolog upregulation. This inhibits the protein kinase B (PI3K/Akt) pathway, hampering SC proliferation and differentiation, and blocking new myotube formation to repair atrophy. Neutralizing circulating FGF21 using neutralizing antibodies, knockdown of hepatic FGF21 by adeno-associated virus, or knockout of KLB in SCs effectively improved or reversed DC-related sarcopenia.

CONCLUSIONS

Hepatocyte-derived FGF21 mediates liver-muscle crosstalk, which impairs muscle regeneration via the inhibition of the PI3K/Akt pathway, thereby demonstrating a novel therapeutic strategy for DC-related sarcopenia.

Effects and Costs of Hepatitis C Virus Elimination for the Whole Population in China: A Modelling Study

BACKGROUND AND OBJECTIVE

China has the highest number of hepatitis C virus (HCV) infections in the world. However, it is unclear what levels of screening and treatment are needed to achieve the WHO 2030 hepatitis C elimination targets. We aimed to evaluate the impact of scaling up interventions on the hepatitis C epidemic and determine how and at what cost these elimination targets could be achieved for the whole population in China.

METHODS

We developed a compartmental model incorporating HCV transmission, disease progression, and care cascade for the whole population in China, calibrated with data on demographics, injecting drug use, HCV prevalence, and treatments. Five different scenarios were evaluated for effects and costs for 2022-2030. All costs were converted to 2021 US dollar (USD) and discounted at an annual rate of 5%. One-way sensitivity analyses were conducted to assess the robustness of the model.

RESULTS

Under the status quo scenario, the incidence of hepatitis C is projected to increase from 60.39 (57.60-63.45) per 100,000 person-years in 2022 to 68.72 (65.3-73.97) per 100,000 person-years in 2030, and 2.52 million (1.94-3.07 million) infected patients are projected to die between 2022 and 2030, of which 0.76 (0.61-1.08) million will die due to hepatitis C. By increasing primary screening to 10%, conducting regular rescreening (annually for PWID and every 5 years for the general population) and treating 90% of patients diagnosed, the incidence would be reduced by 88.15% (86.61-89.45%) and hepatitis C-related mortality by 60.5% (52.62-65.54%) by 2030, compared with 2015 levels. This strategy would cost USD 52.78 (USD 43.93-58.53) billion.

CONCLUSIONS

Without changes in HCV prevention and control policy, the disease burden of HCV in China will increase dramatically. To achieve the hepatitis C elimination targets, China needs to sufficiently scale up screening and treatment.

Lactylation signature identifies liver fibrosis phenotypes and traces fibrotic progression to hepatocellular carcinoma

Introduction

Precise staging and classification of liver fibrosis are crucial for the hierarchy management of patients. The roles of lactylation are newly found in the progression of liver fibrosis. This study is committed to investigating the signature genes with histone lactylation and their connection with immune infiltration among liver fibrosis with different phenotypes.

Methods

Firstly, a total of 629 upregulated and 261 downregulated genes were screened out of 3 datasets of patients with liver fibrosis from the GEO database and functional analysis confirmed that these differentially expressed genes (DEGs) participated profoundly in fibrosis-related processes. After intersecting with previously reported lactylation-related genes, 12 DEGs related to histone lactylation were found and narrowed down to 6 core genes using R algorithms, namely S100A6, HMGN4, IFI16, LDHB, S100A4, and VIM. The core DEGs were incorporated into the Least absolute shrinkage and selection operator (LASSO) model to test their power to distinguish the fibrotic stage.

Results

Advanced fibrosis presented a pattern of immune infiltration different from mild fibrosis, and the core DEGs were significantly correlated with immunocytes. Gene set and enrichment analysis (GSEA) results revealed that core DEGs were closely linked to immune response and chemokine signaling. Samples were classified into 3 clusters using the LASSO model, followed by gene set variation analysis (GSVA), which indicated that liver fibrosis can be divided into status featuring lipid metabolism reprogramming, immunity immersing, and intermediate of both. The regulatory networks of the core genes shared several transcription factors, and certain core DEGs also presented dysregulation in other liver fibrosis and idiopathic pulmonary fibrosis (IPF) cohorts, indicating that lactylation may exert comparable functions in various fibrotic pathology. Lastly, core DEGs also exhibited upregulation in HCC.

Discussion

Lactylation extensively participates in the pathological progression and immune infiltration of fibrosis. Lactylation and related immune infiltration could be a worthy focus for the investigation of HCC developed from liver fibrosis.

Metabolic dysregulation-triggered neutrophil extracellular traps exacerbate acute liver failure

Acute liver failure (ALF) is an acute liver disease with a high mortality rate in clinical practice, characterized histologically by extensive hepatocellular necrosis and massive neutrophil infiltration. However, the role of these abnormally infiltrating neutrophils during ALF development is unclear. Here, in an ALF mouse model, metabolites were identified that promote the formation of neutrophil extracellular traps (NETs) in the liver, subsequently influencing macrophage differentiation and disease progression. ALF occurs with abnormalities in hepatic and intestinal metabolites. Abnormal metabolites (LTD4 and glutathione) can directly, or indirectly via reactive oxygen species, promote NET formation of infiltrating neutrophils, which subsequently regulate macrophages in a pro-inflammatory M1-like state, inducing an amplification of the destructive effects of inflammation. Together, this study provides new insights into the role of NETs in the pathogenesis of ALF.

HDAC inhibitors support long-term expansion of porcine hepatocytes in vitro

Hepatocyte transplantation is an effective treatment for end-stage liver disease. However, due to the limited supply of human hepatocytes, porcine hepatocytes have garnered attention as a potential alternative source. Nonetheless, traditional primary porcine hepatocytes exhibit certain limitations in function maintenance and in vitro proliferation. This study has discovered that by using histone deacetylase inhibitors (HDACi), primary porcine hepatocytes can be successfully reprogrammed into liver progenitor cells with high proliferative potential. This method enables porcine hepatocytes to proliferate over an extended period in vitro and exhibit increased susceptibility in lentivirus-mediated gene modification. These liver progenitor cells can readily differentiate into mature hepatocytes and, upon microencapsulation transplantation into mice with acute liver failure, significantly improve the survival rate. This research provides new possibilities for the application of porcine hepatocytes in the treatment of end-stage liver disease.

Trends of liver transplantation in Asia

Liver transplantation (LT) in Asia started comparatively early in 1964, just 1 year after Starzl's trail-blazing first attempt. Despite the quick start, LT was slow to develop in this region. Limited access to universal healthcare, lack of public understanding and support as well as the absence of strong legislation, on a backdrop of a wide range of diverse social, religious, economic and cultural background are all contributory factors. Through strong administrative efforts, the number of DDLTs in selected Asian countries has been slowly rising in recent years. However, Asians are generally still less likely to donate organs than Caucasians after death. The strong demand for LT with limited access to deceased organs has, therefore, led to constant need for innovation in LT this region, with the pioneering of various LDLT techniques and safe expansion of donor pool being driven primarily by Asian centers. Familiarity and the development of technical expertise in donor surgery have also resulted in Asian centers repeatedly pushing the boundaries on minimally invasive donor and recipient surgery. In this article, we focus on the past and present states of LT in Asia and explore the future trends of LT in this region.

Wogonin Alleviates DCD Liver Ischemia/Reperfusion Injury by Regulating ALOX15/iNOS-mediated Ferroptosis

BACKGROUND

Donation after circulatory death livers are more susceptible to ischemia/reperfusion injury (IRI) because of a longer period of warm ischemia. Growing evidence now suggests that ferroptosis plays a key regulatory role in the development of IRI, so targeting ferroptosis may be an effective strategy to alleviate IRI in liver transplantation (LT).

METHODS

Using donation after circulatory death LT models in rats and oxygen-glucose deprivation/reoxygenation (OGD/R) models in BRL-3A cells, we tested the effect of the Chinese medicine monomer wogonin on liver IRI and explored the specific mechanism.

RESULTS

Wogonin attenuated liver IRI and increased the survival rate of rats by inhibiting lipid peroxidation and ferroptosis. Mechanistically, arachidonic acid 15-lipoxygenase-1 (ALOX15) and inducible nitric oxide synthase (iNOS) were identified as potential targets of baicalein through bioinformatics analysis combined with in vivo and in vitro experiments. This result was further confirmed by molecular docking and cellular thermal shift assays. Finally, we silenced ALOX15 and iNOS in the OGD/R cell model and found that silencing ALOX15 and iNOS could reproduce the regulatory effect of wogonin and abrogate the regulatory effect of wogonin.

CONCLUSIONS

In brief, this study emphasizes that wogonin exerts a protective effect in liver IRI through the regulation of ALOX15- and iNOS-mediated ferroptosis. ALOX15 and iNOS are potential targets for intervention in IRI induced by LT, and wogonin is a drug candidate for LT patients.

Risk Factors for Unplanned Readmission in Adult Liver Transplant Patients: A Retrospective Study

INTRODUCTION

Unplanned readmission is an important indicator for evaluating medical care quality. Adult liver transplant patients have high risk for readmission, which seriously affects their recovery. As there is currently a lack of research on risk factors for unplanned readmission of adult liver transplant patients in China, the purpose of this study was to elucidate such risk factors.

METHODS

Data for patients undergoing liver transplantation surgery at a tertiary hospital in Zhejiang Province from March 2018 to July 2022 were retrospectively collected. Patients were divided into readmission and nonreadmission groups based on whether unplanned readmission occurred within 90 days. Univariate analysis and logistic regression were used to analyze risk factors for unplanned readmission.

RESULTS

In total, 123 adult liver transplant patients were included; 38 had unplanned readmission, for a rate of 30.8%. There was a statistically significant difference between the groups in terms of age, educational level, operation time, intraoperative bleeding volume, number of complications, postoperative hospital stay, and hemoglobin (P < .05). Logistic regression analysis showed that age [OR = 1.085, 95% CI (1.022, 1.152)], operation time [OR = 1.010, 95% CI (1.001, 1.020)], postoperative hospital stay [OR = 1.124, 95% CI (1.023, 1.235)], and number of complications [OR = 4.487, 95% CI (1.234, 16.319)] were independent risk factors for unplanned readmission in adult liver transplant patients (P < .05).

CONCLUSIONS

The current situation of unplanned readmission for adult liver transplant patients cannot be ignored, indicating that staff should identify risk factors for unplanned readmission as soon as possible and take targeted personalized measures and health education to reduce readmission risk.

Short-term postoperative bacteriobilia or fungibilia in liver transplantation patients with donation after circulatory death allografts associated with a longer hospital stay: A single-center retrospective observational study in China

BACKGROUND

Normal bile is sterile. Studies have shown that cholangitis after liver transplantation (LT) was associated with a relatively poor prognosis. It remains unclear whether the bacteriobilia or fungibilia impact the patient outcomes in LT recipients, especially with donation after circulatory death (DCD) allografts, which was correlated with a higher risk of allograft failure.

METHODS

This retrospective study included 139 LT recipients of DCD grafts from 2019 to 2021. All patients were divided into two groups according to the presence or absence of bacteriobilia or fungibilia. The prevalence and microbial spectrum of postoperative bacteriobilia or fungibilia and its possible association with outcomes, especially hospital stay were analyzed.

RESULTS

Totally 135 and 171 organisms were isolated at weeks 1 and 2, respectively. Among all patients included in this analysis, 83 (59.7%) developed bacteriobilia or fungibilia within 2 weeks post-transplantation. The occurrence of bacteriobilia or fungibilia (β = 7.43, 95% CI: 0.02 to 14.82, P = 0.049), particularly the detection of Pseudomonas (β = 18.84, 95% CI: 6.51 to 31.07, P = 0.003) within 2 weeks post-transplantation was associated with a longer hospital stay. However, it did not affect the graft and patient survival.

CONCLUSIONS

The occurrence of bacteriobilia or fungibilia, particularly Pseudomonas within 2 weeks post-transplantation, could influence the recovery of liver function and was associated with prolonged hospital stay but not the graft and patient survival.

Comprehensive approach to controlling chronic hepatitis B in China

Hepatitis B virus (HBV) infection was highly endemic in China, where the prevalence of HBsAg was 9.7% in 1992. Comprehensive strategies, including universal infant hepatitis B vaccination with emphasis on timely birth-dose and 3-dose coverage, dramatically reduced the mother-to-infant transmission and early childhood acquisition of HBV, resulting in estimated HBsAg prevalence rates of 5.6% and 0.1% in the general population and among children aged <5 years in 2022, respectively. Clinical guidelines on the prevention and treatment of chronic hepatitis B have been periodically updated based on emerging evidence from clinical research. The continuously improved reimbursement policy and the massively reduced price of antiviral drugs through government negotiation and central procurement have increased treatment accessibility and affordability. However, due to the low rates of diagnosis and treatment, China still faces a large challenge in achieving the 2030 goal of lowering HBV-related mortality by 65%. A public health approach involving concerted efforts from the government, medical community, industry, and society as a whole would be necessary to increase the uptake of HBV tests and treatment to achieve the global goal of eliminating viral hepatitis as a public health threat by 2030.

Approach to Liver Transplantation: Is There a Difference between East and West?

Liver transplantation (LT) remains the only curative treatment for end-stage liver disease as well as acute liver failure. With the exponential increase in organ demand due to the increasing incidence and prevalence of liver diseases, the need to overcome the supply and demand mismatch has arisen. In this review, we discuss the current universal status of LT, emphasizing various LT practices worldwide.

mTOR inhibitor reduces nontumour-related death in liver transplantation for hepatocellular carcinoma

Sirolimus is a regularly applied immunosuppressant for patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC). Sirolimus not only significantly inhibits HCC recurrence but also protects renal function. However, the improvement effect of sirolimus on nontumour-related death in patients is still unknown. The aim of our study was to investigate the therapeutic effect of sirolimus on nontumour-related deaths. In this study, we retrospectively enrolled 403 LT patients with HCC from January 1, 2015, to December 31, 2018. The median follow-up time was 47.1 months. The patients were divided into the sirolimus group (N = 184) and the sirolimus-free group (N = 219). There were no significant differences between the sirolimus group and the sirolimus-free group in survival (P = 0.054). In transplant patients who exceeded the Milan or Hangzhou criteria, the sirolimus group achieved higher survival than the sirolimus-free group (P = 0.005; P = 0.02). Moreover, multivariate analysis showed that sirolimus strongly reduced the hazard ratio (HR) for nontumour-related death in LT patients who exceeded the Milan (HR: 0.42; 95% CI: 0.18-1; P = 0.05) or Hangzhou criteria (HR: 0.26; 95% CI: 0.08-0.89; P = 0.032). HCC recurrence increased the risk of nontumour-related death. In conclusion, sirolimus-based immunosuppression can significantly reduce nontumour-related death in LT patients who exceed the criteria for transplantation. In addition, this finding will further promote the application of sirolimus after liver transplantation for hepatocellular carcinoma.

Bicarbonate ringer's solution could improve the intraoperative acid-base equilibrium and reduce hepatocellular enzyme levels after deceased donor liver transplantation: a randomized controlled study

BACKGROUND

Bicarbonate Ringer's (BR) solution is a direct liver and kidney metabolism-independent HCO3- buffering system. We hypothesized that BR solution would be more effective in improving acid-base equilibrium and more conducive to better liver function than Acetate Ringer's (AR) solution in conventional orthotopic liver transplantation (OLT) patients.

METHODS

Sixty-nine adult patients underwent OLT. Patients in the bicarbonate and acetate groups received BR solution or AR solution as infused crystalloids and graft washing solution, respectively. The primary outcome was the effect on pH and base excess (BE) levels. The secondary outcome measures were the incidence and volume of intraoperative 5% sodium bicarbonate infusion and laboratory indicates of liver and kidney function.

RESULTS

The pH and absolute BE values changed significantly during the anhepatic phase and immediately after transplanted liver reperfusion in the bicarbonate group compared with the acetate group (all P < 0.05). The incidence and volume of 5% sodium bicarbonate infusion were lower in the bicarbonate group than in the acetate group (all P < 0.05). The aspartate transaminase (AST) level at 7 postoperative days and the creatine level at 30 postoperative days were significantly higher in the acetate group than in the bicarbonate group (all P < 0.05).

CONCLUSION

Compared with AR solution, BR solution was associated with improved intraoperative acid-base balance and potentially protected early postoperative liver graft function and reduced late-postoperative renal injury.

Identification of hub genes and potential inhibitory compounds in the process of liver transplantation through transcriptome sequencing

Liver transplantation (LT) is the best choice for patients with end-stage liver diseases. In order to better understand pathophysiological alterations in LT, we aimed to identify potential hub genes and inhibitory compounds involved in the LT process. Four pairs of peripheral blood mononuclear cell (PBMC) samples of the LT recipients before and after surgery were collected and taken for transcriptome sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed for the screened differentially expressed genes (DEGs) between pre- and post-operation groups. Common DEGs were obtained from GO and KEGG enriched pathways, followed by protein-protein interaction (PPI) network construction, hub gene identification, module analysis, and structure-based virtual screening process (SBVS). Compared to the pre-operation stage, 4745 genes were down-regulated and 798 up-regulated after LT. GO analysis showed that the DEGs were enriched in ribosome-related translation regulation, and KEGG analysis indicated that infection and immune-related pathways and diseases were largely enriched. A large number of down-regulated DEGs were not only associated with ribosome-related pathways but also with the alterations of epigenetic modifications, in particular ubiquitination. Moreover, through the PPI network of 29 common genes from GO and KEGG-enriched pathways, 7 hub genes were identified, including PTEN, MYC, EIF2S1, EIF4EBP1, HSP90AB1, TP53, and HSPA8, which were mainly involved in the PI3K-AKT signaling pathway. SBVS of the seed molecule PTEN (PDB code: 1D5R) predicted top hits compounds that may serve as potential inhibitors of PTEN, of which the compound ZINC4235331 had the lowest binding affinity of -10 kcal/mol. The significance of screened hub genes and potential inhibitors involved in the process of LT provides novel therapeutic strategies for improving the outcomes of LT recipients during surgery.

Cell therapy in end-stage liver disease: replace and remodel

Liver disease is prevalent worldwide. When it reaches the end stage, mortality rises to 50% or more. Although liver transplantation has emerged as the most efficient treatment for end-stage liver disease, its application has been limited by the scarcity of donor livers. The lack of acceptable donor organs implies that patients are at high risk while waiting for suitable livers. In this scenario, cell therapy has emerged as a promising treatment approach. Most of the time, transplanted cells can replace host hepatocytes and remodel the hepatic microenvironment. For instance, hepatocytes derived from donor livers or stem cells colonize and proliferate in the liver, can replace host hepatocytes, and restore liver function. Other cellular therapy candidates, such as macrophages and mesenchymal stem cells, can remodel the hepatic microenvironment, thereby repairing the damaged liver. In recent years, cell therapy has transitioned from animal research to early human studies. In this review, we will discuss cell therapy in end-stage liver disease treatment, especially focusing on various cell types utilized for cell transplantation, and elucidate the processes involved. Furthermore, we will also summarize the practical obstacles of cell therapy and offer potential solutions.