Targeting EFHD2 Inhibits Interferon-γ Signaling and Ameliorates Non-Alcoholic Steatohepatitis

BACKGROUND & AIMS

The precise pathomechanisms underlying the development of nonalcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. This study investigates the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in NASH pathogenesis.

METHODS

Hepatic EFHD2 expression was characterized in NASH patients and two diet-induced NASH mouse models. Single-cell RNA-sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma (HCC) were assessed. Molecular mechanisms underlying EFHD2 function were investigated, along with its potential as a therapeutic target by chemical and genetic means.

RESULTS

EFHD2 expression was significantly elevated in liver tissue macrophages/monocytes in both NASH patients and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related HCC. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of interferon-γ receptor-2 (IFNγR2) onto the plasma membrane. This interaction mediates IFNγ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a developed stapled α-helical peptide targeting EFHD2 demonstrated its efficacy in protecting against NASH pathology in mice.

CONCLUSION

Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment.

IMPACT AND IMPLICATIONS

Nonalcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all NAFLD patients progress to NASH. A key challenge is identifying the factors triggering inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of IFNγ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings suggest EFHD2 as a promising target for drug development aimed at NASH treatment.

Laparoscopy-guided percutaneous microwave ablation for symptomatic 12.8 cm hepatic hemangioma with low blood loss and short hospital stay post-operation: A case report and literature review

We described a patient with symptomatic giant hepatic hemangioma (GHH) treated with laparoscopic guided percutaneous microwave ablation (MWA). A 58 years' old woman was referred to our hospital who presented with upper abdominal distension and appetite loss for more than 1 year. The medical history included untreated multiple hepatic hemangiomas (HH) that had been detected 13 years ago and hypertension for more than 12 years. Initial laboratory tests revealed D-dimer mild increase and negative tumor markers. Magnetic resonance (MR) imaging demonstrated multiple nodules of different sizes in the liver and the largest lesion was located on the left lobe (longest diameter 12.8 cm), which replaced the whole enlarged left lobe and compressed the gastric body and inferior vena cava. Contrast-enhanced ultrasound (CEUS) and contrast-enhanced MR imaging both showed the typical enhancement pattern of hemangioma and abnormal perfusion was seen in the surrounding liver parenchyma. With the laparoscopy guidance, we performed microwave ablation till the whole tumor was seen atrophy. The total operation duration was 2 hours, with intra-operative blood loss less than 20 ml. The post-operative course was uneventful. The patient was discharged 3 days after the operation. Abdominal distension decreased, appetite improved, blood pressure controlled at normal level after the operation. MR revealed significant volume reduction of the tumor after the operation.

Melatonin safeguards against fatty liver by antagonizing TRAFs-mediated ASK1 deubiquitination and stabilization in a β-arrestin-1 dependent manner

Melatonin has been previously shown to prevent nonalcoholic fatty liver disease (NAFLD), yet the underlying mechanisms are poorly understood. Here, we identified a previously unknown regulatory action of melatonin on apoptosis signal-regulating kinase 1 (ASK1) signaling pathway in the pathogenesis and development of NAFLD. Although melatonin administration did not alter food intake, it significantly alleviated fatty liver phenotypes, including the body weight gain, insulin resistance, hepatic lipid accumulation, steatohepatitis, and fibrosis in a high-fat diet (HFD)-induced NAFLD mouse model (in vivo). The protection of melatonin against NAFLD was not affected by inactivation of Kupffer cell in this model. In NAFLD mice liver, ASK1 signal cascade was substantially activated, evidence by the enhancement of total ASK1, phospho-ASK1, phospho-MKK3/6, phospho-p38, phospho-MKK4/7, and phospho-JNK. Melatonin treatment significantly suppressed the ASK1 upregulation and the phosphorylation of ASK1, MKK3/6, MKK4/7, p38, and JNK. Mechanistically, we found that lipid stress triggered the interaction between ASK1 and TNF receptor-associated factors (TRAFs), including TRAF1, TRAF2, and TRAF6, which resulted in ASK1 deubiquitination and thereby increased ASK1 protein stability. Melatonin did not alter ASK1 mRNA level; however, it activated a scaffold protein β-arrestin-1 and enabled it to bind to ASK1, which antagonized the TRAFs-mediated ASK1 deubiquitination, and thus reduced ASK1 protein stability. Consistent with these findings, knockout of β-arrestin-1 in mice partly abolished the protection of melatonin against NAFLD. Taken together, our results for the first time demonstrate that melatonin safeguards against NAFLD by eliminating ASK1 activation via inhibiting TRAFs-mediated ASK1 deubiquitination and stabilization in a β-arrestin-1 dependent manner.

Continuous suture of the pancreatic stump and Braun enteroenterostomy in pancreaticoduodenectomy

AIM: To investigate a new modification of pancreaticoduodenectomy (PD)-a mesh-like running suturing of the pancreatic remnant and Braun’s enteroenterostomy.

METHODS: Two hundred and three patients underwent PD from 2009 to 2014 and were classified into two groups: Group A (98 patients), who received PD with a mesh-like running suturing for the pancreatic remnant, and Braun’s enteroenterostomy; and Group B (105 patients), who received standard PD. Demographic data, intraoperative findings, postoperative morbidity and perioperative mortality between the two groups were compared by univariate and multivariate analysis.

RESULTS: Demographic characteristics between Group A and Group B were comparable. There were no significant differences between the two groups concerning perioperative mortality, and operative blood loss, as well as the incidence of the postoperative morbidity, including reoperation, bile leakage, intra-abdominal fluid collection or infection, and postoperative bleeding. Clinically relevant postoperative pancreatic fistula (POPF) and delayed gastric emptying (DGE) were identified more frequently in Group B than in Group A. Technique A (PD with a mesh-like running suturing of the pancreatic remnant and Braun’s enteroenterostomy) was independently associated with decreased clinically relevant POPF and DGE, with an odds ratio of 0.266 (95%CI: 0.109-0.654, P = 0.004) for clinically relevant POPF and 0.073 (95%CI: 0.010-0.578, P = 0.013) for clinically relevant DGE.

CONCLUSION: An additional mesh-like running suturing of the pancreatic remnant and Braun’s enteroenterostomy during PD decreases the incidence of postoperative complications and is beneficial for patients.

Angiopoietin-1 gene-modified human mesenchymal stem cells promote angiogenesis and reduce acute pancreatitis in rats

Mesenchymal stem cells (MSCs) can serve as a vehicle for gene therapy. Angiopoietin-1 (ANGPT1) plays an important role in the regulation of endothelial cell survival, vascular stabilization, and angiogenesis. We hypothesized that ANGPT1 gene-modified MSCs might be a potential therapeutic approach for severe acute pancreatitis (SAP) in rats. Human umbilical cord-derived MSCs with or without transfection with lentiviral vectors containing the ANGPT1 gene were delivered through the tail vein of rats 12 h after induction of SAP. Administration of MSCs alone significantly reduced pancreatic injury and inflammation, as reflected by reductions in pancreatitis severity scores and serum amylase and lipase levels as well as reducing the serum levels of proinflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6). Furthermore, administration of ANGPT1-transfected MSCs resulted in not only further reductions in pancreatic injury and serum levels of proinflammatory cytokines, but also promotion of pancreatic angiogenesis. These results suggest that MSCs and ANGPT1 have a synergistic role in the treatment of SAP. ANGPT1 gene-modified MSCs may be developed as a potential novel therapy strategy for the treatment of SAP.

The SDF-1/CXCR4 axis regulates migration of transplanted bone marrow mesenchymal stem cells towards the pancreas in rats with acute pancreatitis

Stromal cell-derived factor-1 (SDF-1) and its receptor, CXC chemokine receptor-4 (CXCR4), are important regulators in the migration of bone marrow mesenchymal stem cells (BMSCs). However, the mechanisms underlying this effect in acute pancreatitis (AP) have not been investigated. In this study, BMSCs were identified by specific cell surface markers and differentiation potentials, and labeled with chloromethylbenzamido-1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (CM-Dil) for in vivo cell tracking. AP was induced by retrograde infusion of sodium taurocholate into the common bile duct in rats. The expression of SDF-1 in the injured pancreas was determined by immunohistochemistry and western blot analysis. BMSCs were incubated with or without anti-CXCR4 antibody and the contribution of SDF-1 to the migration of BMSCs was investigated. Our results demonstrated that the expression of SDF-1 was significantly increased in the injured pancreas, and that these levels peaked on days 5-7 and began to decrease on day 10. SDF-1 induced a dose-dependent migration of BMSCs in an in vitro transwell migration assay, which was almost completely blocked by AMD3100 (CXCR4-specific antagonist) or anti-CXCR4 antibody. In addition, by encouraging the migration of CM-Dil-labeled BMSCs, the SDF-1/CXCR4 axis facilitated the repair of the injured pancreas. This effect was inhibited by the anti-CXCR4 antibody. Taken together, these results indicate that the interaction of locally produced SDF-1 with CXCR4 on BMSCs, has an important regulatory role in the migration of BMSCs towards the injured pancreas in AP.

Comparison of clinical outcomes of open, laparoscopic and single port appendicectomies

INTRODUCTION

Appendicectomy is the most common surgical procedure performed in general surgery. This study aimed to compare the outcomes of open appendicectomy (OA), laparoscopic appendicectomy (LA) and single port laparoscopic appendicectomy (SPLA).

METHODS

Fifty consecutive patients with suspected acute appendicitis were studied (OA: n=20, LA: n=20, SPLA: n=10). Clinical outcomes were compared between the three groups in terms of operative time, blood loss, postoperative complications, length of hospital stay and cost.

RESULTS

Patient demographics were similar among groups (p>0.05). SPLA was characterised by longer operative time (88.1 minutes vs 35.6 minutes in OA and 33.4 minutes in LA) and higher costs (12.84 thousand Chinese yuan [RMB] vs 8.41 thousand RMB in LA and 4.99 thousand RMB in OA). OA was characterised by more blood loss (9.8ml vs 7.5ml in SPLA and 6.8ml in LA), longer hospital stay (7.5 days vs 3.5 days in LA and 3.4 days in SPLA) and lower costs. The total number of complications was higher for OA (n=2) than for LA and SPLA (n=0) although this was not statistically significant.

CONCLUSIONS

Where feasible, LA should be undertaken as the initial treatment of choice for most cases of suspected appendicitis.

Therapeutic effect of human umbilical cord-derived mesenchymal stem cells in rat severe acute pancreatitis

AIM

To investigate the therapeutic effect of umbilical cord-derived mesenchymal stem cells (UC-MSCs) on rat severe acute pancreatitis (SAP).

METHODS

Rats were randomly divided into three groups (n = 15 per group): control group, SAP group, and SAP+MSCs group. SAP was established by retrograde pancreatic duct injection of 3% sodium taurocholate. In SAP+MSCs group, UC-MSCs at 1 × 10(7) cells/kg were injected via the tail vein 12 h after SAP. Rats (n = 5 per group) were sacrificed on days 1, 3 and 5, and the blood and pancreatic tissues were collected. The levels of serum amylase, lipase, inflammatory cytokines, and anti-inflammatory cytokines were determined. Pathological changes of the pancreas (HE staining) and apoptotic acinar cells (TUNEL staining) were observed under light microscope.

RESULTS

The levels of serum amylase and lipase in SAP group were significantly higher than those in control group (P<0.05). The pancreas in SAP group showed significantly massive edema, inflammation, hemorrhage and necrosis when compared with control group. There were numerous TUNEL-positive apoptotic acinar cells after SAP. However, in SAP+MSCs group, the levels of serum amylase were significantly reduced on days 1, 3, and 5 after MSC transplantation (P<0.01). The serum lipase level in SAP+MSCs group was significantly lower than that in SAP group on days 3 and 5 (P<0.01). The edema formation, inflammatory cell infiltration, hemorrhage, and necrosis were reduced significantly attenuated in SAP+MSCs group as compared to SAP group (P<0.05). MSCs significantly reduced the levels of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), but increased the levels of anti-inflammatory cytokines (IL-4 and IL-10) in SAP rats. The number of TUNEL-positive acinar cells was significantly reduced on days 3 and 5 after MSCs transplantation (P<0.01).

CONCLUSION

Transplantation of UC-MSCs significantly inhibits inflammation and decreases pancreatic injury secondary to SAP.

CABYR RNAi plasmid construction and NF-κB signal transduction pathway

AIM: To construct the CABYR RNAi plasmid and study its relation with the nuclear factor (NF)-κB signal transduction pathway.

METHODS: Human CABYR mRNA sequence was obtained from GenBank. The structure of cDNA sequence for the short hairpin RNA was BbsI + sense + loop + antisense + transcription terminator + KpnI + BamHI. A CABYR silencing plasmid was constructed and transfected into the human embryo cell line 293T. Quantitative real-time polymerase chain reaction was used to analyze CABYR and NF-κB gene expression.

RESULTS: The CABYR and NF-κB expressions were detected in 293T cells. The oligonucleotide (5’-GCTCAGATGTTAGGTAAAG-3’) efficiently silenced the expression of CABYR. The expression of NF-κB was not significantly affected by silencing CABYR (P = 0.743).

CONCLUSION: CABYR can be found in the human embryo cell line 293T. Cabyrmid 2 can efficiently silence its target, CABYR, indicating that CABYR is not related with the NF-κB signal transduction pathway.

An electrogenic chloride pump in a zoological membrane

Two widely documented mechanisms of chloride transport across animal plasma membranes are anion-coupled antiport and sodium-coupled symport. No direct genetic evidence has yet been provided for primary active chloride transport despite numerous reports of cellular CI(-)-stimulated ATPases coexisting, in the same tissue, with uphill chloride transport that could not be accounted for by the two common chloride transport processes. CI(-)-stimulated ATPases are a common property of practically all animal cells, with the major location being of mitochondrial origin. It also appears that the plasma membranes of animal cells are sites of CI(-)-stimulated ATPase activity. Recent studies of CI(-)-stimulated ATPase activity and chloride transport in the same membrane system, including liposomes, suggest a mediation by the ATPase in net movement of chloride up its electrochemical gradient across animal plasma membranes. Further studies, especially from a molecular biological perspective, are required to confirm a direct transport role to plasma membrane-localized Cl(-)-stimulated ATPases.