Calreticulin regulates hepatic stellate cell activation through modulating TGF-beta-induced Smad signaling

Liver fibrosis is characterized by excessive deposition of extracellular matrix (ECM) as a wound healing process. Activated hepatic stellate cells (HpSCs) are the major producer of the ECM and play a central role in liver fibrogenesis. It has been widely accepted that elimination of activated HpSCs or reversion to a quiescent state can be a feasible strategy for resolving the disease, further highlighting the urgent need for novel therapeutic targets. Calreticulin (CRT) is a molecular chaperone that normally resides in the endoplasmic reticulum (ER), important in protein folding and trafficking through the secretory pathway. CRT also plays a critical role in calcium (Ca2+) homeostasis, with its Ca2+ storage capacity. In the current study, we aimed to demonstrate its function in directing HpSC activation. In a mouse liver injury model, CRT was up-regulated in HpSCs. In cellular experiments, we further showed that this activation was through modulating the canonical TGF-β signaling. As down-regulation of CRT in HpSCs elevated intracellular Ca2+ levels through a form of Ca2+ influx, named store-operated Ca2+ entry (SOCE), we examined whether moderating SOCE affected TGF-β signaling. Interestingly, blocking SOCE had little effect on TGF-β-induced gene expression. In contrast, inhibition of ER Ca2+ release using the inositol trisphosphate receptor inhibitor 2-APB increased TGF-β signaling. Treatment with 2-APB did not alter SOCE but decreased intracellular Ca2+ at the basal level. Indeed, adjusting Ca2+ concentrations by EGTA or BAPTA-AM chelation further enhanced TGF-β-induced signaling. Our results suggest a crucial role of CRT in the liver fibrogenic process through modulating Ca2+ concentrations and TGF-β signaling in HpSCs, which may provide new information and help advance the current discoveries for liver fibrosis.

Impact of metformin on neocortical development during pregnancy: Involvement of ERK and p35/CDK5 pathways

Metformin, the most commonly prescribed drug for the treatment of diabetes, is increasingly used during pregnancy to address various disorders such as diabetes, obesity, preeclampsia, and metabolic diseases. However, its impact on neocortex development remains unclear. Here, we investigated the direct effects of metformin on neocortex development, focusing on ERK and p35/CDK5 regulation. Using a pregnant rat model, we found that metformin treatment during pregnancy induces small for gestational age (SGA) and reduces relative cortical thickness in embryos and neonates. Additionally, we discovered that metformin inhibits neural progenitor cell proliferation in the sub-ventricular zone (SVZ)/ventricular zone (VZ) of the developing neocortex, a process possibly mediated by ERK inactivation. Furthermore, metformin induces neuronal apoptosis in the SVZ/VZ area of the developing neocortex. Moreover, metformin retards neuronal migration, cortical lamination, and differentiation, potentially through p35/CDK5 inhibition in the developing neocortex. Remarkably, compensating for p35 through in utero electroporation partially rescues metformin-impaired neuronal migration and development. In summary, our study reveals that metformin disrupts neocortex development by inhibiting neuronal progenitor proliferation, neuronal migration, cortical layering, and cortical neuron maturation, likely via ERK and p35/CDK5 inhibition. Consequently, our findings advocate for caution in metformin usage during pregnancy, given its potential adverse effects on fetal brain development.

Immune Responses to Anti-Hepatitis C Virus Antibodies during Pre-Liver Transplantation Direct-Acting Antiviral Therapy in Hepatitis C Virus-Infected Recipients Associated with Post-Liver Transplantation Allograft Injury

BACKGROUND AND AIMS

The impact of antibody responses following direct-acting antiviral (DAA) therapy in hepatitis C virus (HCV)-infected recipients before and after liver transplantation (LT) is still undetermined.

METHODS

In this observational cohort study, we aimed to explore the association between changes in anti-HCV antibody titers following pre-LT DAA therapy and allograft injury, including biliary complications (BCs) and acute cellular rejection (ACR).

RESULTS

A total of 153 cases were enrolled from January 2015 to February 2021. Serum anti-HCV antibody titers were assessed before and after (day 30) LT. Among all recipients, 31/153 (20.3%) had pre-LT DAA therapy (the DAA group) and 122/153 (79.7%) did not undergo pre-LT DAA therapy (the DAA-naïve group). A higher incidence of post-LT BCs was observed in the DAA group (p = 0.028). Compared with the DAA-naïve group, the DAA group had a significantly higher mean level of anti-HCV titer upregulation (p = 0.0024); furthermore, among the recipients with BCs (n = 28) and ACR (n = 41), those in the DAA group exhibited significantly higher mean levels of anti-HCV antibody titer upregulation (p < 0.005).

CONCLUSIONS

In conclusion, we speculate that the upregulation of anti-HCV antibody titers, which might have been induced via the restoration of HCV-specific immune responses through pre-LT DAA therapy, was associated with post-LT allograft injury.

Overexpression of miR-4669 Enhances Tumor Aggressiveness and Generates an Immunosuppressive Tumor Microenvironment in Hepatocellular Carcinoma: Its Clinical Value as a Predictive Biomarker

Accumulating evidence suggests the involvement of tumor-derived exosomes in the development and recurrence of hepatocellular carcinoma (HCC). We previously identified miR-4669 as a highly expressed microRNA in circulating exosomes obtained from patients with post-transplant HCC recurrence. This study aimed to explore how overexpression of miR-4669 affects HCC development and recurrence. The impact of miR-4669 overexpression in Hep3B cells on tumor cell behavior and the tumor microenvironment was evaluated in vitro. In addition, the clinical value of exosomal miR-4669 for the prediction of treatment response to HCC downstaging therapies and following post-transplant HCC recurrence was explored. Overexpression of miR-4669 enhanced migration ability and led to acquired sorafenib resistance with an elevation of sirtuin 1 and long noncoding RNA associated with microvascular invasion. Active release of tumor-derived exosomes and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) contributed to generating an immunosuppressive tumor microenvironment through the induction of M2 macrophage polarization. The retrospective analysis demonstrated the clinical value of exosomal miR-4669 for predicting treatment response to HCC downstaging therapies and for risk assessment of post-transplant HCC recurrence. In summary, the present data demonstrate the impact of exosomal miR-4669 on HCC recurrence through the enhancement of tumor aggressiveness and generation of an immunosuppressive tumor microenvironment.

Liver Graft MicroRNAs Expression in Different Etiology of Acute Jaundice after Living Donor Liver Transplantation

Background: Acute jaundice remains a critical problem following liver transplantation. MicroRNAs (miRNAs) are involved in regulating gene expression related to various disease phenotypes and statuses. Aims: To differentiate acute jaundice etiology after living donor liver transplantation (LDLT), we examined the hepatic miRNA expression patterns in several liver graft pathologies. Methods: Eighty liver transplant recipients undergoing post-LDLT graft biopsy for the evaluation of acute jaundice were enrolled in this 1-year prospective study. Using a real-time quantitative reverse transcription-polymerase chain reaction profiling assay, we identified hepatic miRNA (miRNA-122, miRNA-301, miRNA-133a, and miRNA-21) signatures in various allografts pathologies. Results: Pathologic findings of the 80 recipients were as follows: acute cholangitis (AC), 37 (46%); acute rejection (AR), 20 (25%); recurrent hepatitis (RH), 12 (15%); non-specific pathological change, 6 (8%); and fatty change (FC), 5 (6%). None of these identified hepatic miRNAs expression pattern was significantly correlated with serum parameters, including neutrophil-lymphocyte ratio. In AC, hepatic miRNA-122, miRNA-301, miRNA-133a, and miRNA-21 expression was significantly downregulated (p < 0.05). MicroRNA-122 expression was elevated in cases of AR and RH (p < 0.05); miRNA-301 and miRNA-21 expression was higher in RH than in AC (p < 0.05); and miRNA-133a expression was higher in FC than in AR (p < 0.05). Conclusions: Our study suggests that specific hepatic miRNA expression patterns as a checklist may be useful for differential diagnosis of acute jaundice following liver transplantation.

Improved diagnosis of citrin deficiency by newborn screening using a molecular second-tier test

BACKGROUND

Citrin deficiency is an autosomal recessive disorder caused by variants of the SLC25A13 gene. Although newborn screening (NBS) provides an opportunity for its early diagnosis and treatment, citrin deficiency detection rates remain lower than those estimated.

METHODS

Before 2018, NBS for citrin deficiency was based on citrulline levels alone. In June 2018, a second-tier molecular test was implemented to detect 11 common variants of the SLC25A13 gene and improve the NBS detection rates. This study compares the incidence rates and costs before and after the second-tier implementation.

RESULTS

Prior to 2018, five subjects were diagnosed via NBS, and 12 of 555,449 newborns screened were missed. In comparison, 11 subjects were diagnosed out of 198,071 newborns screened after 2018, and there were no false-negatives. The citrin deficiency detection rate increased from 1/32,673 to 1/18,006 after the second-tier test was implemented, with only a minimal increase in the total cost. The number of false-positive in our cohort was tolerable. Subjects with citrin deficiency may present with borderline elevated citrulline levels; these can remain slightly elevated or increase considerably on retest. Four patients (80%) detected prior to second-tier testing and six patients (55%) detected after it was implemented were identified based on the citrulline levels alone. However, at the time of second blood sampling, the normal citrulline level of five subjects did not exclude a citrin deficiency diagnosis.

CONCLUSIONS

Our study shows that it is vital and cost-effective to employ second-tier molecular testing to improve the detection of citrin deficiency by NBS.

Liver Graft Pathology and Low Serum 25-Hydroxyvitamin D after Living Donor Liver Transplantation

BACKGROUND

Most cases of advanced liver diseases are associated with low serum 25-hydroxyvitamin D and vitamin D deficiency. This phenomenon may occur in living donor liver transplantation (LDLT).

AIMS

We conducted this study to explore the interplay between VDR and CYP2R1 in liver graft and compared our findings with the pathological interpretation of serum 25(OH)D concentration.

METHODS

In total, 60 patients received liver graft biopsy after LDLT and were separated (1:1) into two groups: graft rejection group and graft non-rejection group. We extracted both of the recipients' and donors' serum DNA to investigate the vitamin D receptor (VDR) rs2228530 and CYP2R1 rs10741657 single nucleotide polymorphisms (SNPs) using real-time polymerase chain reaction. We also extracted DNA from liver graft tissues to explore the genetic alleles of VDR rs2228530 and CYP2R1 rs10741657 after LDLT. Serum biochemistry profile and 25(OH)D concentrations were measured before and after LDLT.

RESULTS

There were no significant differences in serum VDR rs2228530 and CYP2R1 rs10741657 genetic alleles between recipients and donors. The percentage of genetic modification was 33.4% (10/30) for the rejection and non-rejection groups in VDR rs2228530, and 66.7% (20/30) for both groups in CYP2R1 rs10741657. Serum 25(OH)D concentrations were significantly lower after LDLT D30 than that before LDLT in the rejection (p = 0.0001) and non-rejection graft pathology (p = 0.0017) groups.

CONCLUSIONS

The presence of low serum 25(OH)D concentrations after LDLT suggested that post-transplant low serum 25(OH)D concentrations may develop with the homogenous phenomenon of VDR rs2228530 and CYP2R1 rs10741657 genetic modifications in recipients regardless of graft pathology.

Early Lipid Metabolic Effects of the Anti-Psychotic Drug Olanzapine on Weight Gain and the Associated Gene Expression

BACKGROUND

Atypical antipsychotics such as olanzapine often cause metabolic side effects such as obesity and diabetes, leading to an increased risk of nonalcoholic fatty liver disease. The aim of the present study was to investigate the effects of olanzapine treatment on hepatic lipid metabolism and its possible relationship with adipose tissue status.

METHODS

Using a female rat model, we investigated the effects of chronic olanzapine administration on the regulation of carbohydrate and lipid metabolism including lipid biosynthesis, oxidation, efflux, and lipolysis in liver and adipose tissue.

RESULTS

The body weight, liver mass and visceral adiposity after olanzapine treatment (2 mg/kg) for five weeks were not significantly different compared with vehicle controls. The serum level of triglycerides was higher in the vehicle controls than in olanzapine-treated rats. Unexpectedly, olanzapine treatment did not reduce glucose tolerance in our model. The expression of functional thermogenic protein uncoupling protein 1 (UCP1) was increased in brown adipose tissue (BAT) of the olanzapine group. Additionally, olanzapine treatment also reduced adipose inflammation in white adipose tissue (WAT). The transcription factor sterol regulatory element-binding protein (SREBP)-1c, a key early regulator of lipogenesis, was downregulated following olanzapine treatment. The expression of genes related to the triglycerides synthesis apparatus in the liver was upregulated in the olanzapine group. Olanzapine treatment induced genes involved in PPAR-α signaling and mitochondrial fatty acid oxidation in response to increased ATGL-mediated lipolysis in the liver.

CONCLUSION

Together, our findings suggest a complicated link between olanzapine therapy and metabolic disturbance and may garner interest in assessing the action of antipsychotic-induced metabolic disturbances.

Emerging Roles of Calcium Signaling in the Development of Non-Alcoholic Fatty Liver Disease

The liver plays a central role in energy metabolism. Dysregulated hepatic lipid metabolism is a major cause of non-alcoholic fatty liver disease (NAFLD), a chronic liver disorder closely linked to obesity and insulin resistance. NAFLD is rapidly emerging as a global health problem with currently no approved therapy. While early stages of NAFLD are often considered benign, the disease can progress to an advanced stage that involves chronic inflammation, with increased risk for developing end-stage disease including fibrosis and liver cancer. Hence, there is an urgent need to identify potential pharmacological targets. Ca²⁺ is an essential signaling molecule involved in a myriad of cellular processes. Intracellular Ca²⁺ is intricately compartmentalized, and the Ca²⁺ flow is tightly controlled by a network of Ca²⁺ transport and buffering proteins. Impaired Ca²⁺ signaling is strongly associated with endoplasmic reticulum stress, mitochondrial dysfunction and autophagic defects, all of which are etiological factors of NAFLD. In this review, we describe the recent advances that underscore the critical role of dysregulated Ca²⁺ homeostasis in lipid metabolic abnormalities and discuss the feasibility of targeting Ca²⁺ signaling as a potential therapeutic approach.

Sunlight Exposure and Phototherapy: Perspectives for Healthy Aging in an Era of COVID-19

Most humans depend on sunlight exposure to satisfy their requirements for vitamin D₃. However, the destruction of the ozone layer in the past few decades has increased the risk of skin aging and wrinkling caused by excessive exposure to ultraviolet (UV) radiation, which may also promote the risk of skin cancer development. The promotion of public health recommendations to avoid sunlight exposure would reduce the risk of skin cancer, but it would also enhance the risk of vitamin D₃ insufficiency/deficiency, which may cause disease development and progression. In addition, the ongoing global COVID-19 pandemic may further reduce sunlight exposure due to stay-at-home policies, resulting in difficulty in active and healthy aging. In this review article, we performed a literature search in PubMed and provided an overview of basic and clinical data regarding the impact of sunlight exposure and vitamin D₃ on public health. We also discuss the potential mechanisms and clinical value of phototherapy with a full-spectrum light (notably blue, red, and near-infrared light) as an alternative to sunlight exposure, which may contribute to combating COVID-19 and promoting active and healthy aging in current aged/superaged societies.

HCV RNA in serum and liver samples of patients undergoing living donor liver transplantation

Objective

To compare hepatitis C virus (HCV) RNA levels from serum and explanted native liver samples from patients undergoing living donor liver transplantation (LDLT).

Methods

This was a prospective observational study. Serum and liver samples were collected from consecutive serum anti-HCV-positive transplant recipients between February 2016 to August 2019. HCV RNA was extracted from liver samples and subjected to one-step reverse-transcription qPCR. using the TopScript One Step qRT-PCR Probe Kit with HCV qPCR probe assay and human GAPDH qPCR probe assay on a ViiA7 Real-Time PCR System.

Results

Among the 80 patients, 36% (29/80) were HCV RNA positive in serum and 85% (68/80) had positive hepatic HCV RNA. Post-liver transplantation, 4% (3/80) patients were serum positive.

Conclusions

Our study suggests that pre-transplant serum HCV RNA levels may give an underestimate of the number of positive HCV RNA cases and that hepatic HCV RNA data may be more accurate.

Structural Reorganization of Imidazolium Ionic Liquids Induced by Pressure-Enhanced Ionic Liquid-Polyethylene Oxide Interactions

Mixtures of polyethylene oxide (PEO, M.W.~900,000) and imidazolium ionic liquids (ILs) are studied using high-pressure Fourier-transform infrared spectroscopy. At ambient pressure, the spectral features in the C-H stretching region reveal that PEO can disturb the local structures of the imidazolium rings of [BMIM]+ and [HMIM]+. The pressure-induced phase transition of pure 1-butyl-3-methylimidazolium bromide ([BMIM]Br) is observed at a pressure of 0.4 GPa. Pressure-enhanced [BMIM]Br-PEO interactions may assist PEO in dividing [BMIM]Br clusters to hinder the aggregation of [BMIM]Br under high pressures. The C-H absorptions of pure 1-hexyl-3-methylimidazolium bromide [HMIM]Br do not show band narrowing under high pressures, as observed for pure [BMIM]Br. The band narrowing of C-H peaks is observed at 1.5 GPa for the [HMIM]Br-PEO mixture containing 80 wt% of [HMIM]Br. The presence of PEO may reorganize [HMIM]Br clusters into a semi-crystalline network under high pressures. The differences in aggregation states for ambient-pressure phase and high-pressure phase may suggest the potential of [HMIM]Br-PEO (M.W.~900,000) for serving as optical or electronic switches.

Genetic alterations in gastric cancer patients according to sex

To date, few reports have investigated the genetic alterations and clinicopathological features in gastric cancer (GC) according to sex. In total, 2673 GC patients receiving curative surgery were enrolled. Among the 2673 GC patients, 1979 (74.0%) patients were male. After propensity-score matching, 846 patients were enrolled for the analysis, including 423 males and 423 females. There was no significant difference in the clinicopathological features between the sexes. Regarding the initial recurrence pattern, the males were more likely to develop tumor recurrence and liver metastasis than the females, especially in stage III GC. Regarding the molecular analysis, the males had higher PD-L1 expression than the females, especially in stage III GC. In addition, the patients aged ≥ 65 years had higher PD-L1 expression than the patients younger than 65 years. The multivariate analysis demonstrated that sex was among the independent prognostic factors affecting overall survival (OS) and disease-free survival (DFS). Among the patients with liver metastases, PD-L1 expression was more common among the aged male patients. The males were associated with more tumor recurrence and higher PD-L1 expression than the females, especially in stage III GC. For GC patients with liver metastases, PD-L1 testing is recommended, especially among aged male patients.

Incidence and Risk Factors of Alcohol Relapse after Liver Transplantation: Analysis of Pre-Transplant Abstinence and Psychosocial Features

Alcohol-associated liver disease (ALD) is a common indication for liver transplantation (LT). Alcohol relapse after LT is associated with graft loss and worse prognosis. Over the past 20 years, the number and prevalence of living donor liver transplantations (LDLTs) have increased in Taiwan. The aims of this retrospective study are to analyze the incidence and risk factors of alcohol relapse after LT at a single center in Taiwan. A total of 98 patients with ALD who underwent LT from January 2012 to December 2018 were retrospectively evaluated by chart review. Pre-transplant characteristics as well as psychosocial and alcoholic history were used to test the possible associations among the risk factors studied and post-LT alcohol relapse. The incidence of post-LT alcohol relapse was 16.3%. The median duration of alcohol relapse after liver transplantation was 28.1 months (range: 1–89.4 months). The cumulative incidence was 12% and 19% at 1 year and 3 years after LT, respectively. The most powerful risk factors were a pre-LT abstinence period less than 6 months and younger age of starting alcohol. For predicting alcohol relapse, the accuracy rate of abstinence less than 6 months was up to 83.7%. In summary, pre-abstinence period plays a role in predicting post-LT alcohol relapse. Post-LT interventions should be considered specifically for the patients with short abstinence period. Long-term follow-up, patient-centered counseling, and enhancement of healthy lifestyle are suggested to prevent alcohol relapse.

MicroRNA-301a inhibition enhances the immunomodulatory functions of adipose-derived mesenchymal stem cells by induction of macrophage M2 polarization

MicroRNAs (miRNAs) are a class of short non-coding RNAs that play a significant role in biological processes in various cell types, including mesenchymal stem cells (MSCs). However, how miRNAs regulate the immunomodulatory functions of adipose-derived MSCs (AD-MSCs) remains unknown. Here, we showed that modulation of miR-301a in AD-MSCs altered macrophage polarization. Bone marrow (BM)-derived macrophages were stimulated with LPS (1 μg/ml) and co-cultured with miRNA transfected AD-MSCs for 24 h. The expression of M1 and M2 markers in macrophages was analyzed. Inhibition of miR-301a induced M2 macrophage with arginase-1, CD163, CD206, and IL-10 upregulation. Additionally, toll-like receptor (TLR)-4 mRNA expression in macrophages was downregulated in co-cultures with AD-MSCs transfected with a miR-301a inhibitor. Nitric oxide (NO) in the supernatant of AD-MSC/macrophage co-culture was also suppressed by inhibition of miR-301a in AD-MSCs. We further found that suppression of miR-301a in AD-MSCs increased prostaglandin E₂ (PGE2) concentration in the conditioned medium of the co-culture. Taken together, the results of our study indicate that miR-301a can modulate the immunoregulatory functions of AD-MSCs that favor the applicability as a potential immunotherapeutic agent.

Simultaneous Determination of l-Phenylalanine, Phenylethylamine, and Phenylacetic Acid Using Three-Color Whole-Cell Biosensors within a Microchannel Device

The neurotransmitter phenylethylamine (PEA) is highly susceptible to oxidation to produce phenylacetic acid (PA). The fact that PEA and PA are both metabolites of phenylalanine (Phe) in humans makes them important indicators in the diagnosis of phenylketonuria. In this work, three-color whole-cell biosensors were developed to simultaneously detect these analytes (Phe, PEA, and PA). The tyrosine-responsive promoter was used to control the production of green fluorescent protein signals in response to Phe levels. The FeaR regulon was first used to indicate the presence of PEA, whereas the Paa regulon was used for the detection of PA. The combination of three sensor strains together made it possible to semiquantify the three analytes according to unique color outputs without cross-interference. We sought to optimize various modular components (ribosomal binding sites and fluorescent proteins) to ensure the rapid generation of fluorescent signals. Finally, the biosensors were implemented within a microchannel device to reduce sample consumption in point-of-care assays.

Decreased PEDF Promotes Hepatic Fatty Acid Uptake and Lipid Droplet Formation in the Pathogenesis of NAFLD

Non-alcoholic fatty liver disease (NAFLD), the leading cause of chronic liver diseases worldwide, ranges from simple steatosis to steatohepatitis, with the risk for progressive fibrosis or even cirrhosis. While simple steatosis is a relatively benign condition, the buildup of toxic lipid metabolites can induce chronic inflammation, ultimately triggering disease progression. Pigment epithelium-derived factor (PEDF) is a secreted, multifunctional glycoprotein with lipid metabolic activities. PEDF promotes lipolysis through binding to adipose triglyceride lipase (ATGL), a key enzyme for triglyceride breakdown. In the current study, we aimed to delineate how changes in PEDF expression affect hepatic lipid accumulation. Our data revealed that hepatic PEDF was downregulated in a mouse NAFLD model. We further showed that decreased PEDF levels in hepatocytes in vitro resulted in elevated fatty acid uptake and lipid droplet formation, with concomitant upregulation of fatty acid transport proteins CD36 and fatty acid binding protein 1 (FABP1). RNA sequencing analysis of PEDF knocked down hepatocytes revealed an alteration in gene expression profile toward lipid accumulation. Additionally, decreased PEDF promotes mobilization of fatty acids, an observation distinct from blocking ATGL activity. Taken together, our data suggest that hepatic PEDF downregulation causes molecular changes that favor triglyceride accumulation, which may further lead to NAFLD progression.

Decreased PEDF Expression Promotes Adipogenic Differentiation through the Up-Regulation of CD36

Adipogenesis is a tightly regulated cellular process that involves the action of multiple signaling pathways. Characterization of regulators that are associated with adipose development is crucial to understanding the mechanisms underlying obesity and other metabolic disorders. Pigment epithelium-derived factor (PEDF) is a secreted glycoprotein that was first described as a neurotrophic factor. The role of PEDF in lipid metabolism was established when adipose triglyceride lipase (ATGL), a major triglyceride hydrolase, was characterized as its binding partner. In this study, we investigated the downstream effects of PEDF on adipogenic differentiation using rat adipose-derived stem cells (AdSCs) and the mouse pre-adipocyte cell line 3T3-L1. Knocking down PEDF in differentiating cells resulted in elevated levels of ATGL and CD36, as well as other adipogenic markers, with a concomitant increase in adipocyte number. CD36, a scavenger receptor for a variety of ligands, regulated proliferation and lipogenic gene expression during adipogenesis. The CD36 increase due to PEDF down-regulation might be a result of elevated PPARγ. We further demonstrated that PEDF expression was regulated by dexamethasone, a synthetic glucocorticoid that is widely used for adipogenesis at the transcriptional level. Taken together, our findings highlight that PEDF negatively regulates adipogenesis through the regulation of various signaling intermediates, and it may play a crucial role in lipid metabolic disorders.

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

BACKGROUND & AIMS

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.

METHODS

We prospectively collected 60 donor/recipient pairs from our liver transplantation programmes and extracted serum DNA to evaluate single nucleotide polymorphisms in CYP27A1 rs4674344, CYP27B1 rs10877012, CYP2R1 rs10741657, and VDR rs2228530 alleles using real-time polymerase chain reaction. We measured serum 25(OH)D concentrations of donors (D-D0) and recipients before (R-D0) and after (R-D30) living donor liver transplantation for comparison with repeated-measures analysis of variance in generalized estimating equations analysis.

RESULTS

Fatty liver disease was noted in 28.3% of the cases after living donor liver transplantation, and the graft rejection rate was 25%. There were significant differences in low serum 25(OH)D concentrations between D-D0 and R-D0 and between R-D0 and R-30 groups. Significant associations were observed for serum CYP27A1 rs4674344 in recipients and donors as well as for graft liver tissue with VDR rs2228530. There was no significant relationship with serum CYP27B1 rs10877012 in recipients and donors or with graft liver tissue with CYP2R1 rs10741657.

CONCLUSIONS

Donor/recipient CYP27A1 rs4674344 and graft VDR rs2228570 may be related to low serum 25(OH)D and may play a major role in the development of fatty liver disease in recipients after living donor liver transplantation.

Identification of IL-28B Genotype Modification in Hepatocytes after Living Donor Liver Transplantation by Laser Capture Microdissection and Pyrosequencing Analysis

The aim of this study is to elucidate the biogenetic modification of donor and recipient interleukin-28B (IL-28B) genotypes in liver graft biopsies after living donor liver transplantation (LDLT) for chronic hepatitis C virus- (HCV-) related, end-stage liver disease. Fifty liver graft biopsies were collected from recipients during LDLT treatment for HCV-related, end-stage liver disease. DNA was extracted from all 50 liver tissues, and the IL-28B single-nucleotide polymorphisms (SNPs) rs8099917 and rs12979860 were studied for allelic discrimination by real-time PCR analysis. Blood samples were obtained from donors and recipients on postoperative day 0 (POD0), POD7, and POD30. We randomly selected five liver biopsies and isolated the hepatocytes by laser capture microdissection (LCM) to evaluate genotype modifications resulting from LDLT. After LDLT, the IL-28B SNP rs8099917 was identified not only in the liver graft biopsies and donors' sera (TT = 41 : 43; GT = 9 : 5; GG = 0 : 2), but also in liver graft biopsies and recipients' sera on POD0 (TT = 41 : 44; GT = 9 : 4; GG = 0 : 2), POD7 (TT = 41 : 30; GT = 9 : 18; GG = 0 : 2), and POD30 (TT = 41 : 29; GT = 9 : 19; GG = 0 : 2). A significant difference was observed between the rs8099917 allele frequencies of liver graft biopsies and recipients' sera on POD30 (p = 0.039). In addition, a significant difference was also noted between the rs12979860 allele frequencies of liver graft biopsies and donors' sera (CT = 49 : 39; TT = 1 : 10) (p = 0.012) and of liver graft biopsies and recipients' sera on POD0 (CT = 49 : 39; TT = 1 : 11) (p = 0.002), POD7 (CT = 49 : 42; TT = 1 : 8) (p = 0.016), and POD30 (CT = 49 : 41; TT = 1 : 9) (p = 0.008). This phenomenon was confirmed by pyrosequencing of hepatocytes isolated by LCM. Following LDLT, the TT-to-GT IL-28B genotype modification predominated in rs8099917, and the CC-to-CT modification predominated in rs12979860. In conclusion, these modified phenomena suggested that the selected donor with a predictable and favourable IL-28B genotype will not confer a benefit on the recipient in the living donor liver transplantation setting.

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.

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.

Overexpression of Insig-2 inhibits atypical antipsychotic-induced adipogenic differentiation and lipid biosynthesis in adipose-derived stem cells

Atypical antipsychotics (AAPs) are considered to possess superior efficacy for treating both the positive and negative symptoms of schizophrenia; however, AAP use often causes excessive weight gain and metabolic abnormalities. Recently, several reports have demonstrated that AAPs activate sterol regulatory element-binding protein (SREBP). SREBP, SREBP cleavage-activating protein (SCAP) and insulin-induced gene (Insig) regulate downstream cholesterol and fatty acid biosynthesis. In this study, we explored the effects of clozapine, olanzapine and risperidone on SREBP signaling and downstream lipid biosynthesis genes in the early events of adipogenic differentiation in adipose-derived stem cells (ASCs). After the induction of adipogenic differentiation for 2 days, all AAPs, notably clozapine treatment for 3 and 7 days, enhanced the expression of SREBP-1 and its downstream lipid biosynthesis genes without dexamethasone and insulin supplementation. Simultaneously, protein level of SREBP-1 was significantly enhanced via inhibition of Insig-2 expression. By contrast, SREBP-1 activation was suppressed when Insig-2 expression was upregulated by transfection with Insig-2 plasmid DNA. In summary, our results indicate that AAP treatment, notably clozapine treatment, induces early-stage lipid biosynthesis in ASCs. Such abnormal lipogenesis can be reversed when Insig-2 expression was increased, suggesting that Insig/SCAP/SREBP signaling may be a therapeutic target for AAP-induced weight gain and metabolic abnormalities.

Therapeutic potential of α-lipoic acid derivative, sodium zinc histidine dithiooctanamide, in a mouse model of allergic rhinitis

BACKGROUND

Oxidative stress is involved in various diseases, including allergies. Several studies have pointed to the preventive and therapeutic potential of antioxidants in allergic disorders. However, little is known about the immunomodulatory effects of antioxidants in type I hypersensitivity. In this study we aimed to explore the impact of a water-soluble antioxidant and α-lipoic acid derivative, sodium zinc histidine dithiooctanamide (DHL-HisZn), on mast-cell- and T-cell-mediated allergic and immune responses both in vitro and in vivo.

METHODS

The therapeutic impact of DHL-HisZn on mast-cell-mediated type I hypersensitivity was evaluated by a mast-cell degranulation assay using bone marrow-derived mast cells and by a mouse model of ovalbumin (OVA)-induced allergic rhinitis. The effect of DHL-HisZn on the proportion of regulatory T cells (Tregs) was evaluated using flow cytometry.

RESULTS

During the course of OVA-induced allergic rhinitis in mice, serum nitrate was elevated, suggesting the involvement of oxidative stress in allergic responses. DHL-HisZn not only suppressed mast-cell degranulation but also ameliorated OVA-induced nasal hypersensitivity, with significant suppression of serum nitrate. DHL-HisZn treatment significantly suppressed OVA-specific immunoglobulin E (IgE) but enhanced OVA-specific IgG2a in OVA-sensitized and nasal-challenged mice. Furthermore, DHL-HisZn treatment suppressed interleukin-17 production in OVA-stimulated splenocytes. Finally, we demonstrated the induction of Tregs by DHL-HisZn in concanavalin A blasts.

CONCLUSIONS

These findings suggest that DHL-HisZn may regulate mast-cell-, T-helper 2 (Th2)-, and Th17-mediated allergic and immune responses by induction of Tregs.

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

AIM

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.

METHODS

The transplantation of small-sized Lewis donor livers into green fluorescent protein (GFP) transgenic Wistar rats was performed and the recipients were randomly assigned to one of four groups (without treatment, DPP-IV inhibitor treatment, G-CSF treatment and G-CSF/DPP-IV inhibitor combination). Recombinant human G-CSF was injected s.c. at a dose of 2 μg/kg per day starting 5 days prior to transplantation. G-CSF was combined with the p.o. administration of a DPP-IV inhibitor (2 mg/kg per day) after transplantation until the end of the observation period.

RESULTS

The post-transplant survival and liver function of rats treated with G-CSF/DPP-IV inhibitor combination therapy were significantly improved with an increased number of recipient-derived GFP positive cells into the liver grafts. A confocal microscopy study showed cytokeratin (CK)-18 and GFP positive hepatic progenitor cells in the parenchyma of the liver allografts. Untreated rats and rats treated with either G-CSF or DPP-IV inhibitor did not exhibit the prolonged survival and had less GFP and CK-18 positive cells in the liver grafts after SFS LT.

CONCLUSION

Our results suggest that combined treatment with G-CSF and DPP-IV inhibitor may synergistically induce migration and differentiation of recipient-derived stem cells into the hepatic progenitor cells, resulting in the amelioration of SFS liver graft syndrome.

Isolation of Human Neural Stem Cells from the Amniotic Fluid with Diagnosed Neural Tube Defects

Human neural stem cells (NSCs) are particularly valuable for the study of neurogenesis process and have a therapeutic potential in treating neurodegenerative disorders. However, current progress in the use of human NSCs is limited due to the available NSC sources and the complicated isolation and culture techniques. In this study, we describe an efficient method to isolate and propagate human NSCs from the amniotic fluid with diagnosed neural tube defects (NTDs), specifically, anencephaly. These amniotic fluid-derived NSCs (AF-NSCs) formed neurospheres and underwent long-term expansion in vitro. In addition, these cells showed normal karyotypes and telomerase activity and expressed NSC-specific markers, including Nestin, Sox2, Musashi-1, and the ATP-binding cassette G2 (ABCG2). AF-NSCs displayed typical morphological patterns and expressed specific markers that were consistent with neurons, astrocytes, oligodendrocytes, and dopaminergic neurons after proper induction conditions. Furthermore, grafted AF-NSCs improved the physiological functions in a rat stroke model. The ability to isolate and bank human NSCs from this novel source provides a unique opportunity for translational studies of neurological disorders.

Repeated-measures implication of hepatocellular carcinoma biomarkers in living donor liver transplantation

Objective

Hepatocellular carcinoma (HCC) and its recurrence are major problems in living donor liver transplantation (LDLT). Several biomarkers have been used to investigate this event. We conducted a prospective controlled study to determine the activities of the basic fibroblast growth factor (FGF-2), survivin, Ki67, endostatin, and vascular endothelial growth factor (VEGF) in different conditions before, early after, and late after LDLT with and without HCC recurrence.

Methods

Fifty patients with virus-related HCC who underwent LDLT were enrolled in this 2-year cross-sectional study. During the study period, recurrent HCC was identified in 9 patients (study group, n = 9) and 41 patients (control group, n = 41) had no recurrence after LDLT. The mean time to HCC recurrence was 587.11 ± 398.64 days (range, 90–1352 days). Microvascular invasion (MVI) was found in 66.7% (6/9) of the recipients, as determined on pathological examination. The serum biomarkers were investigated by using enzyme-linked immunosorbent assay at the different LDLT stages.

Results

The serum levels of the biomarkers significantly correlated with LDLT and HCC recurrence in the repeated-measures analysis (F = 31.676, P = 0.000). Significant differences were observed in the effects of all biomarkers (F = 85.313, P = 0.000) and the time to HCC recurrence after LDLT (F = 3.178, P = 0.046). The biomarkers, ordered by the observed power of the test for HCC recurrence after LDLT, were FGF-2 (1.000) > survivin (0.999) > Ki67 (0.949) > endostatin (0.411) > VEGF (0.305).

Conclusions

Different biomarker activities may be implicated in the pathogenesis of HCC recurrence after LDLT. Oncogenes may not exist in the new graft but may still be present in the peripheral blood. The timing of HCC recurrence and impact of MVI in the explanted liver requires confirmation in larger studies with a longer follow-up.

Cytochrome P450 in living donor liver transplantation

Cytochrome P450 metabolizes many drugs in the liver. Three genotypes of CYP2C19 with extensive, intermediate, and poor metabolizing activity, respectively, have been identified in peripheral blood of transplant recipients and new liver grafts in living donor liver transplantation (LDLT). The expression of the final genotype in liver graft biopsies depends on the donor, whereas the expression in peripheral blood mononuclear cells depends on the recipient. The metabolizing isoenzyme of the major anti-rejection agents passes through CYP3A4, CYP3A5 and MDR1, which have also been identified to have similar biological characteristics as genotype of CYP2C19 in liver tissue. Recently, pyrosequencing has been used to investigate the expressions of different genotypes in liver grafts in LDLT. This review focuses on recent findings regarding the biological expressions of the CYP2C19, CYP3A4, CYP3A5 and MRD1 genotypes in liver grafts before and after LDLT. The application of pyrosequencing may be beneficial in further research on liver transplantation. Laser capture microdissection of hepatocytes in liver grafts may be a direction for future research.

Homogeneous phenomenon of the graft when using different genotype characteristic of recipients/donors in living donor liver transplantation

AIM: To investigate the evidence of homogeneous phenomenon on CYP3A5*3 MDR1-3435 and CYP3A4*18 of the liver graft after living donor liver transplantation (LDLT).

METHODS: We identified the proportional change of the CYP3A5*3, MDR1-3435 and CYP3A4*18 from the peripheral blood mononuclear cell of 41 pairs recipient/donor with different genotype polymorphisms and 119 liver graft biopsy samples used with the pyrosequencing technique after LDLT. Polymerase chain reaction/ligase detection reaction assay and restriction fragment length polymorphism was employed for genotyping the CYP3A5*3 and CYP3A4*18 single nucleotide polymorphisms (SNPs). All of the recipients and donors expressed with the similar SNP genotype of CYP3A5*3, MDR1-3435 or CYP3A4*18 were excluded.

RESULTS: The final genetic polymorphisms of the liver graft biopsy samples of CYP3A5*3, MDR1-3435 and CYP3A4*18 was predominated depends on the donor with restriction fragment length polymorphism and seems to be less related to the recipient. The proportional changes of G to A alleles of the 119 samples of CYP3A5*3 (included A > A/G, A/G > A, A/G > G, G > A, G > A/G and A > G), C to T alleles of the 108 samples of MDR1-3435 (included C > C/T, C/T > C, C/T > T, T > C/T and T > C), and T to C alleles of 15 samples of CYP3A4*18 (included T/C > T and T > C/T) were significant different between the recipients and the liver graft biopsy samples (P < 0.0001) and less difference when compared with the donors in the pyrosequencing analysis after LDLT.

CONCLUSION: The CYP3A5*3, MDR1-3435 and CYP3A4*18 of the recipient could be modified by the donor so-called homogenous phenomenon when the recipient’s blood drained into the liver graft.

Recent advances in chitosan-based nanoparticles for oral delivery of macromolecules

Chitosan (CS), a cationic polysaccharide, is widely regarded as a safe and efficient intestinal absorption enhancer of therapeutic macromolecules, owing to its inherent mucoadhesive feature and ability to modulate the integrity of epithelial tight junctions reversibly. By using CS-based nanoparticles, many studies have attempted to protect the loaded macromolecules against acidic denaturation and enzymatic degradation, prolong their intestinal residence time, and increase their absorption by the intestinal epithelium. Derivatives of CS such as quaternized CS, thiolated CS and carboxylated CS have also been examined to further enhance its effectiveness in oral absorption of macromolecular drugs. This review article describes the synthesis of these CS derivatives and their characteristics, as well as their potential transport mechanisms of macromolecular therapeutics across the intestinal biological membrane. Recent advances in using CS and its derivatives as carriers for oral delivery of hydrophilic macromolecules and their effects on drug transport are also reviewed.

Biological interactions of CYP2C19 genotypes with CYP3A4*18, CYP3A5*3, and MDR1-3435 in living donor liver transplantation recipients

Background

Polymorphisms in CYP2C19 are related to the metabolic oxidation of drugs to varying degrees. The CYP3A4*18, CYP3A5*3, and MDR1-3435 variant alleles are very important, particularly in tacrolimus metabolism in organ transplant rejection.

Aim

The aim of this study is o explore possible interactions among different CYP2C19 genotypes, namely, between homozygous extensive metabolizers (HomEM), heterozygous extensive metabolizers (HetEM), and poor metabolizers (PM), and the CYP3A4*18, CYP3A5*3, and MDR1-3435 variants in living donors and patients who received a living donor liver transplant (LDLT).

Methods

This prospective study enrolled 133 living donors and 133 corresponding recipients. On the basis of the HomEM, HetEM, and PM CYP2C19 genotypes, the distributions of CYP3A4*18 (exon 10; T878C), CYP3A5*3 (intron 3; A6986G), and MDR1-3435 (exon 26; C3435T) genotypes were analyzed for single nucleotide polymorphisms among donors and recipients.

Results

Among 102 HomEM genotypes, including 56 donors and 46 recipients, 91.2% of individuals harbored the T/T genotype of CYP3A4*18; 53.9% possessed G/G, and 34.3% had A/G genotypes of CYP3A5*3; and 38.2% had C/C and 50.0% had C/T genotypes at MDR1-3435. Among 130 HetEM genotypes, including 58 donors and 72 recipients, 97.7% of individuals possessed T/T genotype at CYP3A4*18; 50.0% harbored G/G and 41.5% had A/G genotypes at CYP3A5*3; and 40.0% had C/C and 49.2% had C/T genotypes at MDR1-3435. In 34 PMs, including 19 donors and 15 recipients, 88.2% had T/T genotypes at CYP3A4*18; 41.2% had G/G and 58.8% had A/G genotypes at CYP3A5*3; and 47.1% possessed C/C and 47.1% had C/T genotypes at MDR1-3435. On the basis of the CYP2C19 genotypes, no statistically significant distribution of genotypes were observed between donors and recipients for all genotypes of CYP3A4*18, CYP3A5*3, and MDR1-3435 (P >0.05).

Conclusions

In conclusion, the CYP2C19 genotypes do not affect the expression of CYP3A4*18, CYP3A5*3, or MDR1-3435 variants, which are independently distributed among donors and recipients during LDLT.

Identification of miR-27b as a novel signature from the mRNA profiles of adipose-derived mesenchymal stem cells involved in the tolerogenic response

Adipose-derived mesenchymal stem cells (adipose-derived MSCs, ASCs) possess the ability to differentiate into multiple tissue types and have immune-modulatory properties similar to those of MSCs from other origins. However, the regulation of the MSC-elicited immune-modulatory activity by specific microRNA (miRNA) mechanisms remains unexplored. Gene expression profiling with knowledge-based functional enrichment analysis is an appropriate approach for unraveling these mechanisms. This tool can be used to examine the transcripts and miRNA regulators that differentiate the rat tolerogenic orthotopic liver transplantation (OLT; DA liver into PVG) and rejection OLT (DA liver into LEW) models. In both models, the rejection reaction was observed on postoperative day 7∼14 (rejection phase) but was overcome only by the PVG recipients. Thus, the global gene expression patterns of ASCs from spontaneously tolerant (PVG) and acute rejecting (LEW) rats in response to LPS activation were compared. In this study, we performed miRNA enrichment analysis based on the analysis of pathway, gene ontology (GO) terms and transcription factor binding site (TFBS) motif annotations. We found that the top candidate, miR-27, was specifically enriched and had the highest predicted frequency. We also identified a greater than 3-fold increase of miR-27b expression in the ASCs of tolerant recipients (DA to PVG) compared to those of rejecting recipients (DA to LEW) during the rejection phase in the rat OLT model. Furthermore, our data showed that miR-27b knockdown has a positive influence on the allosuppressive activity that inhibits T-cell proliferation. We found that miR-27 knockdown significantly induced the expression of CXCL12 in cultured ASCs and the expression of CXCL12 was responsible for the miR-27b antagomir-mediated inhibition of T-cell proliferation. These results, which through a series of comprehensive miRNA enrichment analyses, might be relevant for stem cell-based therapeutic applications in immunosuppressive function using ASCs.

Incidence of severe combined immunodeficiency through newborn screening in a Chinese population

BACKGROUND/PURPOSE

In order to know the true incidence of severe combined immunodeficiency (SCID) in a Chinese population, we conducted and implemented SCID newborn screening in Taiwan.

METHODS

Between May 1, 2010 and December 31, 2011, the National Taiwan University Hospital Newborn Screening Center screened all newborns for T-cell lymphopenia by measuring the copy number of T-cell receptor excision circles (TRECs) and RNase P. Newborns with low TREC values were subjected to complete blood cell counts and flow cytometry.

RESULTS

A total of 106,391 newborns were screened using the TREC assay over a period of 19 months. Five newborns were immediately referred for confirmatory tests, including two SCID patients and two patients with persistent T-cell lymphopenia; a third SCID patient was found 2 months after the study period. All three SCID cases received stem cell transplantation at the age of 2-5 months. We also identified five cases of 22q11.2 microdeletion syndrome. During this period, two SCID patients from among the unscreened newborns were reported, and they died at ages 3 months and 4 months, respectively.

CONCLUSION

Newborn screening to measure the number of TREC copies successfully identifies newborns with T-cell lymphopenia, 22q11.2 microdeletion syndrome, and other high-risk conditions. Taken together, the incidence of T-cell lymphopenia in apparently healthy newborns is more than 1 in 11,821, and further attention to their immune functions is warranted.

The effect of exogenous histone H1 on rat adipose-derived stem cell proliferation, migration, and osteogenic differentiation in vitro

Adipose-derived stem cells (ASCs) are of great interest for the development of novel cell therapies due to their ease of isolation and expansion, immunosuppressive activity, and multilineage differentiation potential. However, the mechanisms underlying the therapeutic potential of ASCs remain to be elucidated. Others and we have shown that nuclear proteins such as histone H1 and high mobility group box 1 (HMGB1) play important roles in the maturation of dendritic cells (DCs). Furthermore, we previously demonstrated translocation of histone H1 from the nucleus to the cytoplasm and activation of mitogen-activated protein kinases (MAPKs) in DCs. In the present study, we confirmed that histone H1 does not alter the immunophenotype and immunosuppression potential of ASCs, but that histone H1 enhanced wound healing and increased interleukin (IL)-6 expression. Moreover, histone H1 treated-ASCs showed up-regulation of MAPKs extracellular-regulated kinase 1/2 (ERK1/2) and sequential NF-κB translocation. Finally, we found that culture in differentiation media supplemented with histone H1 enhanced ASC osteogenesis. In contrast, inhibition of histone H1 by small interfering RNA (siRNA) reduced osteogenic differentiation markers including ALP. These results suggest that histone H1 may be useful for induction of mesenchymal stem cells in tissue engineering and future potential ASC therapies.

Algorithm for Pompe disease newborn screening: results from the Taiwan screening program

BACKGROUND

Pompe disease is caused by a deficiency in acid α-glucosidase (GAA) and results in progressive, debilitating, and often life-threatening symptoms. Newborn screening has led to the early diagnosis of Pompe disease, but the best algorithm for screening has not yet been established.

MATERIALS AND METHODS

GAA and neutral α-glucosidase (NAG) activities in dried blood spots (DBSs) were assayed using 4-methylumbelliferyl-β-d-glucopyranoside as the substrate. We also measure α-galactosidase A (GLA) activity in DBSs for comparison. A total of 473,738 newborns were screened for Pompe disease, and the data were analyzed retrospectively to determine the best screening algorithm.

RESULTS

The fluorescence assay used in the screening possessed good reproducibility, but the NAG/GAA ratio was superior in separating the true-positive from the false-positive cases. An NAG/GAA cutoff ratio≥60 produces a positive predictive value (PPV) of 63.4%, and in our sample, only two cases of later-onset Pompe disease would have been missed. The GLA/GAA ratio is not as effective as the NAG/GAA ratio.

CONCLUSION

A suitable control enzyme can improve the performance of newborn screening. Newborn screening for Pompe disease can be performed using the NAG/GAA ratio as a cutoff even in the presence of GAA partial deficiency.

Immunological and regenerative aspects of hepatic mast cells in liver allograft rejection and tolerance

The precise roles of mast cells in liver allograft rejection and tolerance are still unknown. This study aimed to explore the roles of mast cells in immune regulation and liver regeneration for tolerance induction by using rat models of orthotopic liver transplantation (OLT). Stem cell factor (SCF) and its receptor c-Kit, which are critical to the migration and development of not only stem cells but also mast cells, significantly increased in the tolerogenic livers as compared with rejected livers. The significant elevation of mast cell tryptase, high-affinity IgE receptor, and histamine suggested the activation of mast cells in liver allografts at the tolerogenic phase after OLT. Immunohistochemical analysis using confocal microscope clearly showed colocalization of mast cells, Foxp3+ Tregs, γδ T cells, and recipient-derived hepatic progenitor cells with higher expression of SCF, IL-9, IL-10, TGF-β1, and IL-17 related to immunoregulation and liver regeneration in the donor grafts of a tolerogenic OLT model. Cross-talk among mast cells and other cells was evaluated by in vitro studies demonstrating that syngeneic bone marrow-derived mast cells (BMMCs) co-cultured with naïve splenocytes or primary hepatocytes significantly increased the population of splenic γδ T cells by mitogen stimulation or by mast cell degranulation, and also significantly induced the hepatocyte proliferation, respectively. Our results suggested that mast cells in the donor grafts may play important roles in the induction/maintenance of immune tolerance and liver regeneration resulting in the replacement of hepatic cells from donor to recipient.

pH-responsive nanoparticles shelled with chitosan for oral delivery of insulin: from mechanism to therapeutic applications

Despite advances in drug-delivery technologies, successful oral administration of protein drugs remains an elusive challenge. When protein drugs are administered orally, they can rapidly denature or degrade before they reach their targets. Such drugs also may not absorb adequately within the small intestine. As a protein drug for treating diabetes, insulin is conventionally administered via subcutaneous (SC) injection, yet often fails to achieve the glucose homeostasis observed in nondiabetic subjects. Some of this difference may relate to insulin transport: normally, endogenously secreted insulin moves to the liver via portal circulation. When administered subcutaneously, insulin moves through the body via peripheral circulation, which can produce a peripheral hyperinsulinemia. In addition, because SC treatment requires multiple daily injections of insulin, patients often do not fully comply with treatment. Oral administration of exogenous insulin would deliver the drug directly into the liver through portal circulation, mimicking the physiological fate of endogenously secreted insulin. This characteristic may offer the needed hepatic activation, while avoiding hyperinsulinemia and its associated long-term complications. This Account demonstrates the feasibility of using chitosan nanoparticles for oral insulin delivery. Nanoparticle (NP) delivery systems may provide an alternative means of orally administering protein drugs. In addition to protecting the drugs against a harmful gastric environment, the encapsulation of protein drugs in particulate carriers can avert enzymatic degradation, while controlling the drug release and enhancing their absorption in the small intestine. Our recent study described a pH-responsive NP system composed of chitosan (CS) and poly(γ-glutamic acid) for oral delivery of insulin. As a nontoxic, soft-tissue compatible, cationic polysaccharide, CS also adheres to the mucosal surface and transiently opens the tight junctions (TJs) between contiguous epithelial cells. Therefore, drugs made with CS NPs would have delivery advantages over traditional tablet or powder formulations. This Account focuses on the premise that these CS NPs can adhere to and infiltrate the mucus layer in the small intestine. Subsequently, the infiltrated CS NPs transiently open the TJs between epithelial cells. Because they are pH-sensitive, the nanoparticles become less stable and disintegrate, releasing the loaded insulin. The insulin then permeates through the opened paracellular pathway and moves into the systemic circulation.

A surveillance system to reduce transmission of pandemic H1N1 (2009) influenza in a 2600-bed medical center

Background

Concerns have been raised about how the transmission of emerging infectious diseases from patients to healthcare workers (HCWs) and vice versa could be recognized and prevented in a timely manner. An effective strategy to block transmission of pandemic H1N1 (2009) influenza in HCWs is important.

Methodology/Principal Findings

An infection control program was implemented to survey and prevent nosocomial outbreaks of H1N1 (2009) influenza at a 2,600-bed, tertiary-care academic hospital. In total, 4,963 employees at Kaohsiung Chang Gung Memorial Hospital recorded their temperature and received online education on control practices for influenza infections. Administration records provided vaccination records and occupational characteristics of all HCWs. Early recognition of a pandemic H1N1 (2009) influenza case was followed by a semi-structured questionnaire to analyze possible routes of patient contact, household contact, or unspecified contact. Surveillance spanned August 1, 2009 to January 31, 2010; 51 HCWs were confirmed to have novel H1N1 (2009) influenza by quantitative real-time reverse transcription polymerase chain reaction. Prevalence of patient contact, household contact, or unspecified contact infection was 13.7% (7/51), 13.7% (7/51), and 72.5% (37/51), respectively. The prevalence of the novel H1N1 infection was significantly lower among vaccinated HCWs than among unvaccinated HCWs (p<0.001). Higher viral loads in throat swabs were found in HCWs with patient and household contact infection than in those with unspecified contact infection (4.15 vs. 3.53 copies/mL, log₁₀, p = 0.035).

Conclusion

A surveillance system with daily temperature recordings and online education for HCWs is important for a low attack rate of H1N1 (2009) influenza transmission before H1N1 (2009) influenza vaccination is available, and the attack rate is further decreased after mass vaccination. Unspecified contact infection rates were significantly higher than that of patient contact and household contact infection, highlighting the need for public education of influenza transmission in addition to hospital infection control.

Mechanism and consequence of chitosan-mediated reversible epithelial tight junction opening

In order to increase the absorption of hydrophilic macromolecules in the small intestine, permeation enhancers such as chitosan (CS) and its derivatives have been evaluated. The aim of the current work was to investigate, on molecular levels, the effect of CS on tight junction (TJ) integrity in Caco-2 cells. The observed changes in transepithelial-electrical-resistance measurements and the staining patterns of the monolayer Caco-2 cells demonstrate that CS can transiently and reversibly open the TJs between cells, thus enhancing the paracellular permeability. TJ ultra-structures examined by transmission electron microscopy support the concept that CS did induce transient opening of TJs. We then assessed TJ disruption at the gene and protein expression levels. Our data indicate that exposure to CS followed by recovery resulted in a significant increase in claudin-4 (Cldn4) gene transcription. Additionally, CS treatment induced redistribution of the TJ protein CLDN4 intracellularly following by its degradation in lysosomes, which represented an important contributing factor in TJ weakening, leading to the opening of TJs. The recovery of TJ after CS disruption required CLDN4 protein synthesis. These results suggest that CS regulates TJs by inducing changes in transmembrane CLDN4 protein. Understanding the mechanism of interaction between CS and epithelial cells is of paramount importance and needs to be established to aid further development in the use of CS to mediate the trans-epithelial drug delivery.

Adaptor protein Shc acts as an immune-regulator for the LPS-stimulated maturation of bone marrow-derived dendritic cells

Background

The Shc isoforms is known to mediate immune responses and has been indicated as a negative regulator of autoimmunity and lymphocyte activation. We aimed to evaluate the immune-regulatory role of Shc in rat bone marrow-derived DCs in the maturation process triggered by LPS.

Results

We found that, in response to LPS, expression of Shc proteins was induced and that neutralization of Shc inhibited the LPS-induced transient phosphorylation of p52Shc on pTyr239/240 in DCs of Lewis (LEW; RT1^l) rats. Moreover, the significantly enhanced expression of IL-10 and the surface level of costimulatory molecule CD80, as well as suppressed expression of IL-6 and IL-12 in the Shc-silenced DCs were also observed. Similar IκB phosphorylation occurred in Shc-silenced DCs primed by LPS, indicating Shc is not associated with NF-κB pathway. We further demonstrate that Shc blockade on LPS-treated DCs results in significant increase of the overall STAT3 phosphorylation and the relative levels of phospho-STAT3 in the nuclear fraction. STAT3 activation by LPS with or without Shc blockade was totally abolished by SU6656, a selective Src family kinases inhibitor, underscoring the critical role of Src-mediated activation.

Conclusions

We conclude that Shc blockade in LPS-primed DC leads to the development of tolerogenic DC via Src-dependent STAT3 activation and that adaptor protein Shc might play a pivotal role in mediating immunogenic and tolerogenic properties of DCs.

Cellular cardiomyoplasty with human amniotic fluid stem cells: in vitro and in vivo studies

Human amniotic fluid stem cells (hAFSCs) derived from second-trimester amniocentesis were evaluated for the therapeutic potential of cardiac repair. Whether hAFSCs can be differentiated into cardiomyogenic cells and toward the maturation of endothelial cell lineage was investigated in vitro using mimicking differentiation milieu. Employing an immune-suppressed rat model with experimental myocardial infarction, an intramyocardial injection was conducted with a needle directly into the peri-infarct areas. There were three treatment groups: sham, saline, and hAFSCs (n > or = 10). When cultured with rat neonatal cardiomyocytes or in endothelial growth medium-2 enriched with vascular endothelial growth factor, hAFSCs were differentiated into cardiomyocyte-like cells and cells of endothelial lineage, respectively. After 4 weeks, hAFSC-treated animals showed a preservation of the infarcted thickness, an attenuation of left ventricle remodeling, a higher vascular density, and thus an improvement in cardiac function, when compared with the saline injection group. Survival and proliferation of the transplanted hAFSCs were revealed by immunohistochemical staining. Expressions of the cardiac-specific markers such as Nkx2.5, alpha-actinin, and cardiac Troponin T were observed in the transplanted hAFSCs. Additionally, Cx43 was clearly expressed at the borders of the transplanted/transplanted and host/transplanted cells, an indication of enhancement of cell connection. The results demonstrated that hAFSCs induce angiogenesis, have cardiomyogenic potential, and may be used as a new cell source for cellular cardiomyoplasty.

High concentration of magnolol induces hepatotoxicity under serum-reduced conditions

Although magnolol is cytoprotective against warm ischemia/reperfusion injury, its effect on cold preservation has not been fully investigated. This study aimed at examining whether magnolol maintains the liver graft integrity after cold preservation and elucidating the underlying mechanisms in terms of apoptotic signaling under both normothermic and hypothermic conditions. After being preserved in Ringer's lactate (RL) at 4 degrees C for 6h ex vivo, the magnolol-treated grafts demonstrated significantly higher AST, ALT, and LDH levels in perfusates than those from negative controls. TUNEL staining showed no difference in the number of apoptotic nuclei in both groups, whereas a more intense apoptotic signal in magnolol-treated grafts was shown as compared with the controls. In vitro data showed no significant difference in viability of RL-preserved clone-9 hepatocytes between the magnolol-treated and control groups, while magnolol pretreatment at 30min before cold preservation prominently induced hepatocyte cell death. RT-PCR and Western blotting analyses revealed a suppression in Bcl-2, but an up-regulation in Bax expression in clone-9 cells after magnolol treatment. Magnolol suppressed the ratios of NF-kappaB to I-kappaBalpha protein contents and I-kappaBalpha phosphorylation induced by TNF-alpha, and potentiated mitochondrial cytochrome c release and subsequent caspase-3 cleavage. Conversely, caspase-3 inhibitor attenuated magnolol-induced hepatotoxicity. We concluded that magnolol could not protect liver grafts from cold ischemia/reperfusion injury. High concentration of magnolol under serum-reduced conditions attenuates NF-kappaB-mediated signaling and induces intrinsic apoptotic pathway, thereby inducing in vitro hepatotoxicity.

Chronic administration of cyclosporine A changes expression of BDNF and TrkB in rat hippocampus and midbrain

Neurotrophins, including the brain-derived neurotrophic factor (BDNF), are essential for regulating neuronal differentiation in developing brains. BDNF and its receptor tyrosine kinase receptor B (TrkB) are involved in neuronal signaling, survival and plasticity. Cyclosporine A (CsA) is a potent immunosuppressive agent which prevents allograft rejection in organ transplantation and various immunological diseases. We investigated whether chronic administration of CsA decreases BDNF gene expression in rats, and the influence of CsA on mRNA levels of TrkB receptors was also examined. For 30 days of CsA (10 mg/kg/day) administration, the expression of BDNF and TrkB mRNA was significantly decreased in the hippocampus and midbrain, but there was no significant difference in the cortex. CsA (0, 1, 5 10, 15 ug/ml) down-regulated BDNF and TrkB gene expression through cultured SH-SY5Y cells, as did all-trans retinoic acid (ATRA), and there was no effect on cell viability. These experimental results indicate that suppression of the BDNF and TrkB mRNA, protein level of BDNF expression in the hippocampus and midbrain may be related to altered behavior observed following chronic administration of CsA. A common mechanism of adverse effects of CsA induced depressive symptoms may involve neurotoxicity mediated by down-regulation of brain BDNF and TrkB.