Kuang-Tzu Huang

Regulation of Heme Oxygenase 1 Expression by miR-27b With Stem Cell Therapy for Liver Regeneration in Rats

Adipose-derived mesenchymal stem cells (ASCs) have been considered to be attractive and readily available adult mesenchymal stem cells (MSCs) and are becoming increasingly popular for use in regenerating cell therapy. However, recent evidence attributed a fibrotic potential to MSCs which differentiated into myofibroblasts with highly increased α-smooth muscle actin (α-SMA) expression while transplanted into an injured/regenerating liver in mice. In this study, we studied the role of miR-27b in ASCs and their regenerative potential after partial liver resection in rats. ASCs transfected with control siRNA or miR-27b were intravenously injected into autologous rats undergoing 70% partial hepatectomy (PH). Our data showed that the regenerative capacities of ASCs with overexpressed miR-27b were significantly higher compared with control ASCs. However, the enhanced regeneration, hepatic differentiation, and suppressed liver inflammation, as well as fibrotic activity, were significantly reverted by ZnPP coadministration (heme oxygenase-1 [HO-1] inhibitor) indicating an important role of HO-1 in the regenerating and cytoprotective activities of miR-27b-transfected ASCs. We demonstrated that administration of autologous ASCs overexpressed with miR-27b enhances rapid and early liver regeneration and, importantly, preserves function after PH. The ASCs with miR-27b overexpression might offer a viable therapeutic option to facilitate rapid recovery after liver resection.

MicroRNA-27b Enhances the Hepatic Regenerative Properties of Adipose-Derived Mesenchymal Stem Cells

Adipose-derived mesenchymal stem cells (ASCs) are readily available multipotent mesenchymal progenitor cells and have become an attractive therapeutic tool for regenerative medicine. We herein investigated the mechanistic role of how miR-27b modulated regenerative capacities of ASCs. Intravenous administration of miR-27b-transfected ASCs (ASCs-miR-27b) was conducted after 70% partial hepatectomy (PH). After PH, rats injected with ASCs-miR-27b had decreased inflammatory cytokines and increased hepatocyte growth factor and other related growth factors. We showed that the nature of ASCs-miR-27b to inhibit hepatic stellate cell activation was dependent upon peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) in vitro. Moreover, expression of miR-27b in ASCs induced heme oxygenase-1 (HO-1), resulting in increased production of ATP, protective cytokines/growth factors, and genes involved in mitochondrial biogenesis in a PGC-1α-dependent manner. RNA sequencing (RNA-Seq) analysis revealed drastic transcriptional changes in livers treated with ASCs-miR-27b after PH. The differentially expressed genes classified into “regeneration,” “fibrosis,” and “mitochondrial biogenesis” clusters were mainly mitochondrial. The potential biological context reflecting the effects of PGC-1α by ASCs-miR-27b treatment was also observed by the subnetwork analysis with HO-1 and PGC-1α being the top-ranked regulatory genes. We demonstrate autologous ASCs-miR-27b enhances liver regeneration and, importantly, preserves hepatic function through paracrine actions which offers a viable therapeutic option to facilitate rapid recovery after liver injury.

DHL-HisZn, a novel antioxidant, enhances adipogenic differentiation and antioxidative response in adipose-derived stem cells.

Adipose-derived stem cells (ASCs) are multipotent progenitor cells that have the capacity to differentiate into specific mesenchymal cell lineages including adipocytes in response to environmental cues. Dysfunctional adipose tissue, rather than an excess of adipose tissue, has been proposed as a key factor in the pathogenesis of obesity-related diseases. The insulin-sensitizing effects of antidiabetic drugs are mediated by activation of peroxisome proliferator-activated receptor gamma (PPARγ). Here, we investigated the effects of sodium zinc histidine dithiooctanamide (DHL-HisZn), a strong antioxidant, on PPARγ activation, adipocyte differentiation and insulin sensitivity. Additionally, the effects of DHL-HisZn on cellular antioxidant response and inflammatory cytokine production were also evaluated. In ASCs, DHL-HisZn enhanced adipocyte differentiation and PPARγ expression in a dose-dependent manner. DHL-HisZn also increased the relative abundance of insulin-responsive glucose transporter 4 (GLUT4) and adiponectin mRNA. Furthermore, DHL-HisZn upregulated PPARγ downstream target gene expression. In addition, treatment with DHL-HisZn upregulated mRNA levels of endogenous antioxidants, such as glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase 2 (SOD2), catalase (CAT) and glutathione reductase (GR). DHL-HisZn treatment enhanced insulin signaling and inhibited NF-κB activation, which subsequently suppressed inflammatory cytokine IL-6 expression. Our results indicate that DHL-HisZn enhances insulin sensitivity in adipocytes by increasing the expression of GLUT4 and IRS-1 via the activation of PPARγ and improving the antioxidant response during adipogenic differentiation. Therefore, DHL-HisZn may have the capability to reduce insulin resistance.

Pigment epithelium-derived factor in lipid metabolic disorders

Pigment epithelium-derived factor (PEDF) is a secreted glycoprotein that has anti-angiogenic, anti-proliferative, neurotrophic and immunomodulatory properties. PEDF has recently emerged as a critical metabolic regulatory protein since the discovery of its modulatory activities in the lipolytic pathway by binding to adipose triglyceride lipase (ATGL). Despite being beneficial in maintaining the homeostasis of hepatic lipid accumulation, PEDF has been uncovered an unfavorable role associated with insulin resistance. The molecular events that connect these two apparent distinct observations have been controversial and remained largely unknown. Therefore in this short review, we attempt to summarize the current findings of PEDF regarding its lipid metabolic functions and provide perspectives in identifying PEDF as a potential therapeutic target in lipid disorders.

Factor VII-Induced MicroRNA-135a Inhibits Autophagy and Is Associated with Poor Prognosis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and aggressive malignancies worldwide. Treatment outcomes remain poor mainly due to lack of good diagnostic/prognostic markers and limited therapeutic strategies. We previously characterized aberrant activation of the TF/FVII/PAR2 pathway, which subsequently results in decreased autophagy, as a crucial event in malignant progression of HCC. Here, we identified miR-135a as a highly upregulated miRNA in HCC in response to TF/FVII/PAR2 activation. Analyzing 103 HCC patient specimens, we confirmed that miR-135a was frequently elevated in HCC tissues with higher FVII expression compared to adjacent non-cancerous counterparts. Increased miR-135a levels in HCC were also associated with tumor staging, recurrence, microvascular invasion, and decreased disease-free survival. We subsequently identified Atg14, a key component that regulates the formation of autophagosome as a direct target of miR-135a. Ectopic expression of miR-135a suppressed Atg14 levels and inhibited the autophagic processes. Our results indicate strong positive correlations between miR-135a levels and malignant behaviors in HCC patients and also suggest novel functions of miR-135a in regulation of autophagy, which could be useful as a potential target for prognostic and therapeutic uses.

Prolonged survival by combined treatment with granulocyte colony‐stimulating factor and dipeptidyl peptidase IV inhibitor in a rat small‐for‐size liver transplantation model

Despite the great advances and excellent outcomes of liver transplantation (LT), small‐for‐size (SFS) graft syndrome is a life‐threatening complication that remains to be overcome. In the present study, we investigated the therapeutic effect of combined treatment with granulocyte colony‐stimulating factor (G‐CSF) and a dipeptidyl peptidase IV (DPP‐IV) inhibitor on SFS liver graft syndrome.

Assessment of relevant factors with respect to psychosocial properties in potential living donor candidates before liver transplantation

Background Living donor liver transplantation (LDLT) has been developed as one of gold standard treatments for end-stage liver disease. Mental health is a required selection criterion for adult living liver donors and may influence the quality of life after operation. Patients and methods A total of 1,210 potential living donor candidates for liver transplantation (LT) underwent psychosocial evaluation that included a semi-structured interview, multi-choice self-reported inventory (Beck Depression Inventory-2nd edition [BDI-II], Beck Anxiety Inventory [BAI]), and the family APGAR (Adaptability, Partnership, Growth, Affection, Resolve) index. The test results were compared by family relationships, and subgroups were classified based on the donation type: 1) parents to children, 2) grown children to parents, 3) siblings to siblings, 4) spouses to spouses, and 5) other relatives to other relatives. Results The BDI-II (P < 0.001) and BAI differed considerably according to the donation type in potential donor candidates. Compared with other subgroups, parents donating to their children suffered the most severe psychological stress before LDLT and exhibited more depressive (P < 0.001) and anxiety symptoms. However, the stress associated with grown children donating to their parents, siblings, and spouses was not significantly higher than it was for other relatives. Furthermore, a significant negative correlation existed between family APGAR scores and the severity of depression and anxiety (P < 0.001) among potential donor candidates. Conclusion These results indicate the importance of understanding potential donor candidates’ psychological characteristics before LT. Greater anxiety and depression may be exhibited by parent donors due to the distress from fears of death or illness of the recipients, or their guilty feeling for their child. Additionally, family dysfunction also revealed more depression and anxiety. Such donor candidates should be given more extensive pre-donation counseling for minimizing pre-LDLT psychological stress.

Genetic polymorphisms of the hepatic pathways of fatty liver disease after living donor liver transplantation

Fatty liver disease is an important complication associated with liver transplantation, and the cytochrome P‐450 system of the donor liver may be involved in its pathogenesis. To explore the effects of the CYP27A1, CYP27B1, CYP2R1, and vitamin D receptor pathways on vitamin D maintenance after living donor liver transplantation, we investigated the interplay between serum 25(OH)D and common variants in 60 paired donors and recipients who underwent living donor liver transplantation.

Coagulation factor VII gene polymorphisms are not associated with the occurrence or the survival of hepatocellular carcinoma: a report of 37 cases

Objective : Coagulation factor VII (FVII) triggers the extrinsic pathway of blood coagulation. In our previous study, we showed that FVII plays an important role in tumorigenesis of hepatocellular carcinoma (HCC). However, the role of FVII polymorphism in HCC is still unknown. The present study aimed to investigate the relationship between HCC carcinogenesis and single nucleotide polymorphism of FVII. Methods : Thirty-seven HCC patients and 30 healthy donors were recruited in this study. Four common FVII gene polymorphisms – a decanucleotide insertion at position –323 (–323ins10-bp), a G to T substitution at position –401 (–401G/T), a G to A substitution at position –402 (–402G/A), and a T to C substitution at position –122 (–122T/C) – were analyzed by sequencing or commercialized assays using genomic DNA isolated from blood samples. Clinicopathological parameters between control and HCC subjects were compared according to the specific genotypes. Results : The most common nucleotide variation was –402G/A. However, no statistically significant difference was observed between healthy controls and HCC subjects for all four polymorphisms in terms of genotype distribution and allele frequencies, indicating that these polymorphisms may not affect HCC tumorigenesis. Furthermore, no association was found between –402G/A polymorphisms and tumor stage, recurrence, and overall survival. Conclusions : Our results indicate that FVII polymorphisms may not be a key factor that clinically impact tumorigenesis and outcomes of HCC, although further investigations should be conducted to confirm our findings.

Tumor microenvironment mediated by suppression of autophagic flux drives liver malignancy

The physiological role of autophagy in the catabolic process of the body involves protein synthesis and degradation in homeostasis under normal and stressed conditions. In hepatocellular carcinoma (HCC), the role of tumor microenvironment (TME) has been concerned as the main issue in fighting against this deadly malignancy. During the last decade, the crosstalk between tumor cells and their TME in HCC extensively accumulated. However, a deeper knowledge for the actual function of autophagy in this interconnection which involved in supporting tumor development, progression and chemoresistance in HCC is needed but still largely unknown. Recent studies have shown that coagulants tissue factor (TF) and factor VII (FVII) has a pathological role in promoting tumor growth by activating protease-activated receptor 2 (PAR2). Autophagy-associated LC3A/B-II formation was selectively suppressed by FVII/PAR2 signaling which mediated by mTOR activation through Atg7 but not Atg5/Atg12 axis. The coagulant-derived autophagic suppression seemed potentiate a vicious circle of malignancy in producing more FVII and PAR2 which facilitate in vivo and in vitro tumor progression of HCC and the investigations are consistent with the clinical observations. In this review, we briefly summarize the current understanding of autophagy and discuss recent evidence for its role in HCC malignancy.