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Background The therapeutic effects of human embryonic stem cell-derived multipotent mesenchymal stem cells (M-MSCs) were evaluated for detrusor underactivity (DUA) in a rat model with atherosclerosis-induced chronic bladder ischemia (CBI) and associated mechanisms. Methods Sixteen-week-old male Sprague–Dawley rats were divided into five groups (n = 10). The DUA groups underwent 30 bilateral repetitions of endothelial injury to the iliac arteries to induce CBI, while the sham control group underwent a sham operation. All rats used in this study received a 1.25% cholesterol diet for 8 weeks. M-MSCs at a density of 2.5, 5.0, or 10.0 × 105 cells (250 K, 500 K, or 1000 K; K = a thousand) were injected directly into the bladder 7 weeks post-injury, while the sham and DUA group were treated only with vehicle (phosphate buffer solution). One week after M-MSC injection, awake cystometry was performed on the rats. Then, the bladders were harvested, studied in an organ bath, and prepared for histological and gene expression analyses. Results CBI by iliac artery injury reproduced voiding defects characteristic of DUA with decreased micturition pressure, increased micturition interval, and a larger residual volume. The pathological DUA properties were improved by M-MSC treatment in a dose-dependent manner, with the 1000 K group producing the best efficacy. Histological analysis revealed that M-MSC therapy reduced CBI-induced injuries including bladder fibrosis, muscular loss, and apoptosis. Transplanted M-MSCs mainly engrafted as vimentin and NG2 positive pericytes rather than myocytes, leading to increased angiogenesis in the CBI bladder. Transcriptomes of the CBI-injured bladders were characterized by the complement system, inflammatory, and ion transport-related pathways, which were restored by M-MSC therapy. Conclusions Single injection of M-MSCs directly into the bladder of a CBI-induced DUA rat model improved voiding profiles and repaired the bladder muscle atrophy in a dose-dependent manner. Graphical abstract

Purpose Despite advances in treatment, lung cancer remains the leading cause of cancer mortality. This study aimed to characterise genome-wide tumorigenesis events and to understand the hypothesis of the multistep carcinogenesis of lung adenocarcinoma (LUAD). Materials and methods We conducted multiregion whole-exome sequencing of LUAD with synchronous atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ, or minimally invasive adenocarcinoma of 19 samples from three patients to characterize genome-wide tumorigenesis events and validate the hypothesis of the multistep carcinogenesis of LUAD. We identified potential pathogenic mutations preserved in preinvasive lesions and supplemented the finding by allelic variant level from RNA sequencing. Results Overall, independent mutational profiles were observed per patient and between patients. Some shared mutations including epidermal growth factor receptor (EGFR , p.L858R) were present across synchronous lesions. Conclusion Here, we show that there are driver gene mutations in AAH, and they may exacerbate as a sequence in a histological continuum, supporting the Darwinian evolution model of cancer genome. The intertumoral and intratumoral heterogeneity of synchronous LUAD implies that multi-biomarker strategies might be necessary for appropriate treatment.

Real-time monitoring of GSH dynamics demonstrates the functional roles of CREB1-NRF2 pathway in MSC therapeutic potency., Glutathione (GSH), the most abundant nonprotein thiol functioning as an antioxidant, plays critical roles in maintaining the core functions of mesenchymal stem cells (MSCs), which are used as a cellular immunotherapy for graft-versus-host disease (GVHD). However, the role of GSH dynamics in MSCs remains elusive. Genome-wide gene expression profiling and high-throughput live-cell imaging assays revealed that CREB1 enforced the GSH-recovering capacity (GRC) of MSCs through NRF2 by directly up-regulating NRF2 target genes responsible for GSH synthesis and redox cycling. MSCs with enhanced GSH levels and GRC mediated by CREB1-NRF2 have improved self-renewal, migratory, anti-inflammatory, and T cell suppression capacities. Administration of MSCs overexpressing CREB1-NRF2 target genes alleviated GVHD in a humanized mouse model, resulting in improved survival, decreased weight loss, and reduced histopathologic damages in GVHD target organs. Collectively, these findings demonstrate the molecular and functional importance of the CREB1-NRF2 pathway in maintaining MSC GSH dynamics, determining therapeutic outcomes for GVHD treatment.

Mesenchymal stem cells (MSCs) are of particular interest for the treatment of immune-related diseases due to their immunosuppressive capacity. Here, we show that Small MSCs primed with Hypoxia and Calcium ions (SHC-MSCs) exhibit enhanced stemness and immunomodulatory functions for treating allogeneic conflicts. Compared with naïve cultured human umbilical cord blood-derived MSCs, SHC-MSCs were resistant to passage-dependent senescence mediated via the monocyte chemoattractant protein-1 and p53/p21 cascade and secreted large amounts of pro-angiogenic and immunomodulatory factors, resulting in suppression of T-cell proliferation. SHC-MSCs showed DNA demethylation in pluripotency, germline, and imprinted genes similarly to very small embryonic-like stem cells, suggesting a potential mutual relationship. Genome-wide DNA methylome and transcriptome analyses indicated that genes related to immune modulation, cell adhesion, and the cell cycle were up-regulated in SHC-MSCs. Particularly, polo-like kinase-1 (PLK1), zinc-finger protein-143, dehydrogenase/reductase-3, and friend-of-GATA2 play a key role in the beneficial effects of SHC-MSCs. Administration of SHC-MSCs or PLK1-overexpressing MSCs significantly ameliorated symptoms of graft-versus-host disease (GVHD) in a humanized mouse model, resulting in significantly improved survival, less weight loss, and reduced histopathologic injuries in GVHD target organs compared with naïve MSC-infused mice. Collectively, our findings suggest that SHC-MSCs can improve the clinical treatment of allogeneic conflicts, including GVHD.

Summary The core functions of stem cells (SCs) are critically regulated by their cellular redox status. Glutathione is the most abundant non-protein thiol functioning as an antioxidant and a redox regulator. However, an investigation into the relationship between glutathione-mediated redox capacity and SC activities is hindered by lack of probe. Here, we demonstrate that cyanoacrylamide-based coumarin derivatives are ratiometric probes suitable for the real-time monitoring of glutathione levels in living SCs. These probes revealed that glutathione levels are heterogeneous among subcellular organelles and among individual cells and show dynamic changes and heterogeneity in repopulating SCs depending on oxidative stress or culture conditions. Importantly, a subpopulation of SCs with high glutathione levels exhibited increased stemness and migration activities in vitro and showed improved therapeutic efficiency in treating asthma. Our results indicate that high glutathione levels are required for maintaining SC functions, and monitoring glutathione dynamics and heterogeneity can advance our understanding of the cellular responses to oxidative stress., Graphical Abstract, Highlights • FreSHtracer is a reversible probe for a fast and ratiometric reaction with GSH • FreSHtracer and its derivatives enable real-time monitoring of intracellular GSH • FreSHtracer reports dynamic changes and heterogeneity of GSH level in stem cells • High GSH levels are required for maintaining functional potency of stem cells, By developing and characterizing new fluorescent probes enabling fast, reversible, and ratiometric reaction with glutathione, Jeong et al. reveal considerable dynamics and heterogeneity in glutathione levels in living stem cells in response to environmental stress and also show that high glutathione levels are required for maintaining stemness of murine embryonic stem cells or therapeutic potency of mesenchymal stem cells.

Engraftment and homing of mesenchymal stem cells (MSCs) are modulated by priming factors including the bioactive lipid sphingosine-1-phosphate (S1P), by stimulating CXCR4 receptor signaling cascades. However, limited in vivo efficacy and the remaining priming molecules prior to administration of MSCs can provoke concerns regarding the efficiency and safety of MSC priming. Here, we showed that valproic acid (VPA), a histone deacetylase inhibitor, enforced the priming effect of S1P at a low dosage for human umbilical cord-derived MSCs (UC-MSCs). A DNA-methylation inhibitor, 5-azacytidine (5-Aza), and VPA increased the expression of CXCR4 in UC-MSCs. In particular, UC-MSCs primed with a suboptimal dose (50 nM) of S1P in combination with 0.5 mM VPA (VPA+S1P priming), but not 1 µM 5-Aza, significantly improved the migration activity in response to stromal cell-derived factor 1 (SDF-1) concomitant with the activation of both MAPKp42/44 and AKT signaling cascades. Both epigenetic regulatory compounds had little influence on cell surface marker phenotypes and the multi-potency of UC-MSCs. In contrast, VPA+S1P priming of UC-MSCs potentiated the proliferation, colony forming unit-fibroblast, and anti-inflammatory activities, which were severely inhibited in the case of 5-Aza treatment. Accordingly, the VPA+S1P-primed UC-MSCs exhibited upregulation of a subset of genes related to stem cell migration and anti-inflammation response. Thus, the present study demonstrated that VPA enables MSC priming with S1P at a low dosage by enhancing their migration and other therapeutic beneficial activities. This priming strategy for MSCs may provide a more efficient and safe application of MSCs for treating a variety of intractable disorders.

Molecular programs involved in embryogenesis are frequently upregulated in oncogenic dedifferentiation and metastasis. However, their precise roles and regulatory mechanisms remain elusive. Here, we showed that CDK1 phosphorylation of TFCP2L1, a pluripotency‐associated transcription factor, orchestrated pluripotency and cell‐cycling in embryonic stem cells (ESCs) and was aberrantly activated in aggressive bladder cancers (BCs). In murine ESCs, the protein interactome and transcription targets of Tfcp2l1 indicated its involvement in cell cycle regulation. Tfcp2l1 was phosphorylated at Thr177 by Cdk1, which affected ESC cell cycle progression, pluripotency, and differentiation. The CDK1‐TFCP2L1 pathway was activated in human BC cells, stimulating their proliferation, self‐renewal, and invasion. Lack of TFCP2L1 phosphorylation impaired the tumorigenic potency of BC cells in a xenograft model. In patients with BC, high co‐expression of TFCP2L1 and CDK1 was associated with unfavorable clinical characteristics including tumor grade, lymphovascular and muscularis propria invasion, and distant metastasis and was an independent prognostic factor for cancer‐specific survival. These findings demonstrate the molecular and clinical significance of CDK1‐mediated TFCP2L1 phosphorylation in stem cell pluripotency and in the tumorigenic stemness features associated with BC progression., Aberrant activation of pluripotency genes is frequently observed in tumors. Thr177‐phosphorylation of TFCP2L1 by CDK1 stimulates pluripotency and cell cycling in embryonic stem cells and stemness features of bladder cancers, potentiating the tumorigenesis and aggressive behavior of bladder cancer.

Aims: The naive or primitive states of stem cells (SCs) residing in specific niches are unstable and difficult to preserve in vitro. Vitamin C (VitC), in addition to suppressing oxygen radicals, ex...

Chronic kidney disease (CKD) is characterized by a progressive loss of kidney function over a period of months or years. It is estimated that about 7.2 % of adults over the age of 30 have CKD worldwide. Although one of the major risk factors of CKD is family history, the heritability of CKD is not fully understood. It is also known that the diabetic condition is highly influential on the onset of CKD. To understand the genetic bases of CKD that remain unidentified, we performed genetic association analyses for kidney function-related traits such as blood urea nitrogen (BUN) and albumin in subjects stratified by diabetic status. In the discovery stage of the study, we used genome-wide scan data and clinical data in about 8800 subjects from the Korean Association Resource (KARE) project. Health2 study data comprising about 1800 subjects were used for the replication stage. Our two stage association analyses demonstrated that the LOC105374266 locus (rs9820070) showed strong evidence of association with BUN (P = 8.47 × 10−14) in nondiabetic normal subjects (n = ~4300). To extend our knowledge of the genetic determinants influencing kidney function, we also analyzed the association between kidney function-related traits and microRNA related variants. For this analysis, miRNA related SNPs were selected from KARE and Health2 cohort genotype data. Our study suggests the potential relevance of miRNA to the kidney function (miR-518b for BUN; miR-146a and miR-1295a for albumin) in Korean populations.

Some molecules enriched in damaged organs can contribute to tissue repair by stimulating the mobilization of stem cells. These so-called "priming" factors include bioactive lipids, complement components, and cationic peptides. However, their therapeutic significance remains to be determined. Here, we show that priming of mesenchymal stromal/stem cells (MSCs) with ceramide-1 phosphate (C1P), a bioactive lipid, enhances their therapeutic efficacy in pulmonary artery hypertension (PAH). Human bone marrow (BM)-derived MSCs treated with 100 or 200 μM C1P showed improved migration activity in Transwell assays compared with non-primed MSCs and concomitantly activated MAPK(p42/44) and AKT signaling cascades. Although C1P priming had little effect on cell surface marker phenotypes and the multipotency of MSCs, it potentiated their proliferative, colony-forming unit-fibroblast, and anti-inflammatory activities. In a monocrotaline-induced PAH animal model, a single administration of human MSCs primed with C1P significantly attenuated the PAH-related increase in right ventricular systolic pressure, right ventricular hypertrophy, and thickness of α-smooth muscle actin-positive cells around the vessel wall. Thus, this study shows that C1P priming increases the effects of MSC therapy by enhancing the migratory, self-renewal, and anti-inflammatory activity of MSCs and that MSC therapy optimized with priming protocols might be a promising option for the treatment of PAH patients.

Ubiquinol cytochrome c reductase binding protein (UQCRB) is known to play crucial roles in the development of various types of diseases. However, the link between UQCRB and microRNAs remains unknown. In the present study, we performed microRNA sequencing of mutant UQCRB-expressing stable cell lines that exhibited pro-oncogenic activities caused by expression of the mutant UQCRB gene. Results showed that hsa-miR-10a-5p was significantly downregulated in the mutant UQCRB-expressing cell lines. Furthermore, mRNA sequencing and gene ontology analysis of differentially expressed genes (DEGs) revealed that the cholesterol biosynthesis pathway might be activation by mutant UQCRB expression. Moreover, inhibition of cholesterol synthesis in mutant UQCRB-expressing cells via treatment with the specific inhibitors suppressed the cell proliferation. Transfection with a hsa-miR-10a-5p mimic validated that lanosterol synthase (LSS) is a target of hsa-miR-10a-5p. In addition, hsa-miR-10a-5p was found to be downregulated in liver cancer cell lines overexpressing UQCRB. Taken together, our findings highlighted the potential use of hsa-miR-10a-5p as a biomarker for UQCRB related diseases.

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Aims: Cellular senescence and its secretory phenotype (senescence-associated secretory phenotype [SASP]) develop after long-term expansion of mesenchymal stromal cells (MSCs). Further investigation of this phenotype is required to improve the therapeutic efficacy of MSC-based cell therapies. In this study, we show that positive feedback between SASP and inherent senescence processes plays a crucial role in the senescence of umbilical cord blood-derived MSCs (UCB-MSCs). Results: We found that monocyte chemoattractant protein-1 (MCP-1) was secreted as a dominant component of the SASP during expansion of UCB-MSCs and reinforced senescence via its cognate receptor chemokine (c-c motif) receptor 2 (CCR2) by activating the ROS-p38-MAPK-p53/p21 signaling cascade in both an autocrine and paracrine manner. The activated p53 in turn increased MCP-1 secretion, completing a feed-forward loop that triggered the senescence program in UCB-MSCs. Accordingly, knockdown of CCR2 in UCB-MSCs significantly improved their therapeutic ability to alleviate airway inflammation in an experimental allergic asthma model. Moreover, BMI1, a polycomb protein, repressed the expression of MCP-1 by binding to its regulatory elements. The reduction in BMI1 levels during UCB-MSC senescence altered the epigenetic status of MCP-1, including the loss of H2AK119Ub, and resulted in derepression of MCP-1. Innovation: Our results provide the first evidence supporting the existence of the SASP as a causative contributor to UCB-MSC senescence and reveal a so far unappreciated link between epigenetic regulation and SASP for maintaining a stable senescent phenotype. Conclusion: Senescence of UCB-MSCs is orchestrated by MCP-1, which is secreted as a major component of the SASP and is epigenetically regulated by BMI1. Antioxid. Redox Signal. 24, 471–485.

Spermatogonial stem cells (SSCs), which are unipotent stem cells in the testes that give rise to sperm, can be converted into germline-derived pluripotent stem (gPS) by self-induction. The androgenetic imprinting pattern of SSCs is maintained even after their reprogramming into gPS cells. In this study, we used an in vitro neural differentiation model to investigate whether the imprinting patterns are maintained or altered during differentiation. The androgenetic patterns of H19, Snrpn, and Mest were maintained even after differentiation of gPS cells into NSCs (gPS-NSCs), whereas the fully unmethylated status of Ndn in SSCs was altered to somatic patterns in gPS cells and gPS-NSCs. Thus, our study demonstrates epigenetic alteration of genomic imprinting during the induction of pluripotency in SSCs and neural differentiation, suggesting that gPS-NSCs can be a useful model to study the roles of imprinted genes in brain development and human neurodevelopmental disorders.

Stem cell (SC) therapy has become a potential treatment modality for pulmonary artery hypertension (PAH), but the efficacy of human SC and priming effects have not yet been established. The mobilization and homing of hematopoietic stem cells (HSCs) are modulated by priming factors that include a bioactive lipid, sphingosine-1-phosphate (S1P), which stimulates CXCR4 receptor kinase signaling. Here, we show that priming human mesenchymal stem cells (MSCs) with S1P enhances their therapeutic efficacy in PAH. Human MSCs, similar to HSCs, showed stronger chemoattraction to S1P in transwell assays. Concomitantly, MSCs treated with 0.2 μM S1P showed increased phosphorylation of both MAPKp42/44 and AKT protein compared with nonprimed MSCs. Furthermore, S1P-primed MSCs potentiated colony forming unit-fibroblast, anti-inflammatory, and angiogenic activities of MSCs in culture. In a PAH animal model induced by subcutaneously injected monocrotaline, administration of human cord blood-derived MSCs (hCB-MSCs) or S1P-primed cells significantly attenuated the elevated right ventricular systolic pressure. Notably, S1P-primed CB-MSCs, but not unprimed hCB-MSCs, also elicited a significant reduction in the right ventricular weight ratio and pulmonary vascular wall thickness. S1P-primed MSCs enhanced the expression of several genes responsible for stem cell trafficking and angiogenesis, increasing the density of blood vessels in the damaged lungs. Thus, this study demonstrates that human MSCs have potential utility for the treatment of PAH, and that S1P priming increases the effects of SC therapy by enhancing cardiac and vascular remodeling. By optimizing this protocol in future studies, SC therapy might form a basis for clinical trials to treat human PAH.

Cancer stem cells (CSCs) are cancer cells that possess the ability to undergo continuous proliferation and self-renewal. It has been postulated that CSCs are responsible for tumor growth, heterogeneity, invasion, metastasis, and recurrence. MicroRNAs (miRNAs), small non-coding RNAs of approximately 22 nucleotides, are known to be involved in the maintenance of CSCs. To gain insight into the role of miRNAs in CSCs, we investigated the differential expression of miRNAs in ovarian CSCs compared to non-CSCs. Ovarian CSCs were isolated from the human ovarian cancer cell line SK-OV-3 using two ovarian CSC-specific surface markers, CD44 and CD117. The expression levels of miRNAs in CSCs and non-CSCs were estimated by miRNA sequencing. We detected four up-regulated miRNAs (miR-29a-5p, miR-34c-5p, miR-106a-5p, and miR-424-5p) in ovarian CSCs, and miR-424-5p was validated by real-time qPCR. MiR-424-5p target genes were predicted using several validated target databases and computational algorithms. Pathway analysis indicated that most miR-424-5p target genes are involved in cancer-related biological pathways. Overall, these results suggest that miR-424-5p is a potential regulator of CSCs that endows human ovarian tissue with tumorigenic potential and thus represents a potential therapeutic target for human ovarian cancer.

Genistein, a phyto-estrogen, can potentially replace endogenous estrogens in postmenopausal women, but the underlying molecular mechanisms remain incompletely understood. To obtain insight into the effect of genistein on bone differentiation, RNA sequencing (RNA-seq) analysis was used to detect differentially expressed genes (DEGs) in genistein-treated vs. untreated MC3T3-E1 mouse osteoblastic cells. Osteoblastic cell differentiation was monitored by measuring osteoblast differentiation factors (ALP production, bone mineralization, and expression of osteoblast differentiation markers). From RNA-seq analysis, a total of 132 DEGs (including 52 up-regulated and 80 down-regulated genes) were identified in genistein-treated cells (FDR q-value 1.5). KEGG pathway and Gene Ontology (GO) enrichment analyses were performed to estimate the biological functions of DEGs and demonstrated that these DEGs were highly enriched in functions related to chemotactic cytokines. The functional relevance of DEGs to genistein-induced osteoblastic cell differentiation was further evaluated by siRNA-mediated knockdown in MC3T3-E1 cells. These siRNA knockdown experiments (of the DEGs validated by real-time qPCR) demonstrated that two up-regulated genes (Ereg and Efcab2) enhance osteoblastic cell differentiation, while three down-regulated genes (Hrc, Gli, and Ifitm5) suppress the differentiation. These results imply their major functional roles in bone differentiation regulated by genistein.

Aberrant activation of transglutaminase 2 (TGase2) contributes to a variety of protein conformational disorders such as neurodegenerative diseases and age-related cataracts. The accumulation of improperly folded proteins in the endoplasmic reticulum (ER) triggers the unfolded protein response (UPR), which promotes either repair or degradation of the damaged proteins. Inadequate UPR results in protein aggregation that may contribute to the development of age-related degenerative diseases. TGase2 is a calcium-dependent enzyme that irreversibly modifies proteins by forming cross-linked protein aggregates. Intracellular TGase2 is activated by oxidative stress which generates large quantities of unfolded proteins. However, the relationship between TGase2 activity and UPR has not yet been established. In the present study, we demonstrated that ER stress activated TGase2 in various cell types. TGase2 activation was dependent on the ER stress-induced increase in the intracellular calcium ion concentration but not on the TGase2 protein expression level. Enzyme substrate analysis revealed that TGase2-mediated protein modification promoted protein aggregation concurrently with decreasing water solubility. Moreover, treatment with KCC009, a TGase2 inhibitor, abrogated ER stress-induced TGase2 activation and subsequent protein aggregation. However, TGase2 activation had no effect on ER stress-induced cell death. These results demonstrate that the accumulation of misfolded proteins activates TGase2, which further accelerates the formation of protein aggregates. Therefore, we suggest that inhibition of TGase2 may be a novel strategy by which to prevent the protein aggregation in age-related degenerative diseases.

Mice null for wild-type p53-induced phosphatase 1 (WIP1) display defects in testis development and spermatogenesis, resulting in reduced fertility. However, the molecular mechanism underlying these abnormalities in the testis remains uncharacterized. We report that the phosphatase activity of WIP1 increases Wnt activity through Nemo-like kinase (NLK). WIP1 directly interacted with NLK, which is highly homologous to p38 MAPK, a WIP1 substrate, and dephosphorylated its activation site. The WIP1-mediated inhibition of NLK activity markedly decreased the phosphorylation of lymphoid enhancer-binding factor 1 (LEF1), enhancing its interaction with β-catenin. Additionally, WIP1 depletion impaired germ cell development, as evidenced by the expression of Oct4 and the germ cell-specific markers Ddx4, Nanos3 and Dnd1 during the development of germ cells from Oct4-GFP transgenic (OG2) mouse embryonic stem cells (mESCs). The expression of WIP1, whose level was significantly lower after the differentiation of germ cells from mESCs, occurred in parallel with the expression of germ cell development markers and SRY-box 17 (Sox17), a downstream target of Wnt. These results indicate that WIP1 is essential for germ cell development, which is known to require Wnt activity.

Bariatric surgery has beneficial effects on weight loss and metabolic profiles. Recent evidence suggests that liver-derived hepatokines play a role in the pathophysiology of metabolic diseases. However, few studies have reported longitudinal changes in hepatokines after gastric bypass surgery. We investigated changes in the serum levels of angiopoietin-like protein 6 (Angptl6) and selenoprotein P after gastric bypass surgery. We followed 10 patients who were treated with gastric bypass for weight loss. We measured metabolic parameters and the serum levels of Angptl6 and selenoprotein P before, 1 month after, and 9 months after surgery. We investigated the changes in those hepatokines after surgery and the associations between changes in Angptl6 and selenoprotein P, respectively, and metabolic parameters. Body mass index decreased linearly. Levels of hemoglobin A1c (HbA1c), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (GGT), total cholesterol, triglyceride, LDL cholesterol, and Angptl6 were significantly lower 1 and 9 months after surgery. Fasting plasma glucose was normal throughout the study. Fasting insulin decreased 1 month after surgery but increased 9 months post-surgery. Levels of selenoprotein P increased linearly. Significant correlations were detected between the levels of Angptl6 and LDL cholesterol and fasting insulin. Changes in Angptl6 levels were significantly correlated with changes in total cholesterol and LDL cholesterol. Selenoprotein P levels were inversely correlated with GGT, and changes in selenoprotein P were inversely correlated with changes in homeostasis model assessment for insulin resistance (HOMA-IR). Our results suggest that gastric bypass may alter the serum levels of hepatokines independent of weight loss, and these changes are related to certain hepatic metabolic changes.

Interstitial cystitis (IC) is a syndrome characterized by urinary urgency, frequency, pelvic pain, and nocturia in the absence of bacterial infection or identifiable pathology. IC is a devastating disease that certainly decreases quality of life. However, the causes of IC remain unknown and no effective treatments or cures have been developed. This study evaluated the therapeutic potency of using human umbilical cord-blood-derived mesenchymal stem cells (UCB-MSCs) to treat IC in a rat model and to investigate its responsible molecular mechanism. IC was induced in 10-week-old female Sprague–Dawley rats via the instillation of 0.1 M HCl or phosphate-buffered saline (PBS; sham). After 1 week, human UCB-MSC (IC+MSC) or PBS (IC) was directly injected into the submucosal layer of the bladder. A single injection of human UCB-MSCs significantly attenuated the irregular and decreased voiding interval in the IC group. Accordingly, denudation of the epithelium and increased inflammatory responses, mast cell infiltration, neurofilament production, and angiogenesis observed in the IC bladders were prevented in the IC+MSC group. The injected UCB-MSCs successfully engrafted to the stromal and epithelial tissues and activated Wnt signaling cascade. Interference with Wnt and epidermal growth factor receptor activity by small molecules abrogated the benefits of MSC therapy. This is the first report that provides an experimental evidence of the therapeutic effects and molecular mechanisms of MSC therapy to IC using an orthodox rat animal model. Our findings not only provide the basis for clinical trials of MSC therapy to IC but also advance our understanding of IC pathophysiology.

Tissue and organ rejuvenation and senescence/aging are closely related to the function of stem cells. Thus, stem cells have been considered as guardians for the homeostasis of tissue/organ throughout life span. Recently, we identified a population of pluripotent Oct4+ very small embryonic/epiblast-like stem cells (VSELs) residing in the adult murine bone marrow (BM) and human cord blood (CB). VSELs can differentiate into cells from all three germ layers in vitro culture condition and in vivo tissue regeneration animal models. VSELs express the gene-expression and epigenetic profiling, which are similar to germ-line stem cells including (i) open/active chromatin structure in Oct4 promoter, (ii) parent-of-origin-specific reprogramming of genomic imprinting, (iii) deoxyribonucleic acid (DNA) demethylation in the promoter of germ-line lineage genes, and (iv) reactivate the X chromosome (in female pluripotent stem cells, PSCs). The unique epigenetic reprogramming in VSELs suggest that they could developmentally originate from the migratory primordial germ cells (PGCs) and the proliferation of VSELs are negatively controlled by epigenetic changes of some imprinted genes that regulate insulin/insulin-like growth-factor (Ins/Igf) signaling (Igf2, H19, Igf2R, and Rasgrf1). Since the chronic exposure to Ins/Igf signaling negatively correlates with longevity, we propose that Ins/Igf signaling mediated decrease in the number of VSELs could be a novel explanation of ageing. Therefore, VSELs could play a pivotal role in maintaining the integrity of adult tissues and these cells could provide a therapeutic alternative to stem cells isolated from embryos. Therefore, the understanding the precise molecular signature of VSELs such as reprogrammed genomic imprints could increase the regenerative power of these cells.

The activation of transglutaminase 2 (TG2), an enzyme that catalyzes post-translational modifications of proteins, has been implicated in apoptosis, cell adhesion and inflammatory responses. We previously reported that intracellular TG2 is activated under oxidative stress conditions, such as ultraviolet irradiation, ischemia-reperfusion, and hypoxia. In this study, we examined the effect of genotoxic stress on the intracellular activity of TG2 using doxorubicin which generates reactive oxygen species that lead to double-strand breakage of DNA. We demonstrated that doxorubicin elicits the persistent activation of TG2. Doxorubicin-induced TG2 activity was suppressed by treatment with caffeine at the early phase, N-acetylcysteine at the mid-phase, and EGTA at the late phase. However, treatment with a blocking antibody against TGFβ or toll-like receptor 2 showed no effect on TG2 activity, indicating that at least three different signaling pathways may be involved in the process of TG2 activation. In addition, using MEF cells defective for TG2 and cells overexpressing an activesite mutant of TG2, we revealed that doxorubicin-induced cell death is inversely correlated with TG2 activity. Our findings indicate that the persistent activation of TG2 by doxorubicin contributes to cell survival, suggesting that the mechanism-based inhibition of TG2 may be a novel strategy to prevent drug-resistance in doxorubicin treatment.

PURPOSE The activation of transglutaminase 2 (TG2) by oxidative stress through TGFβ has been reported to play a crucial role in cataract formation. The authors investigated whether TG2 is involved in selenite-induced cataract formation in rats and whether cysteamine, a chemical inhibitor of TG2, can prevent cataract formation in this model. METHODS Intracellular TG2 activity was monitored in a human lens epithelial cell (HLE-B3) line and cultured rat lenses after treatment with selenite. Rat pups (13 days old) were injected subcutaneously with sodium selenite (Na(2)SeO(3); 20 μmol/kg) and intraperitoneally with cysteamine (30, 40, and 60 mg/kg) for 14 days. Lenses were evaluated photographically at days 7 and 14. The concentrations of malondialdehyde and glutathione in the lenses were determined. RESULTS In HLE-B3 cells or rat lenses, selenite induced intracellular TG activity, which was inhibited by cysteamine. In selenite-treated rats, the rate of cataract formation was significantly reduced by cysteamine (P < 0.001). The mean cataract area in the lenses of cysteamine-treated rats was smaller than that of control rats (P < 0.01). The levels of total and reduced glutathione in the lenses of cysteamine-treated rats extracted at day 14 were higher than those of control rats. CONCLUSIONS Cysteamine suppresses cataract formation induced by selenite in rats, suggesting that cysteamine can be used as a pharmaceutical intervention to prevent or delay cataract formation.

BACKGROUND: Modeling of short-term viral dynamics of hepatitis B with traditional biphasic model might be insufficient to explain long-term viral dynamics. The aim was to develop a novel method of mathematical modeling to shed light on the dissociation between early and long-term dynamics in previous studies. METHODS: We investigated the viral decay pattern in 50 patients from the phase III clinical trial of 24-week clevudine therapy, who showed virological response and HBsAg decline. Immune effectors were added as a new compartment in the model equations. We determined some parameter values in the model using the non-linear least square minimization method. RESULTS: Median baseline viral load was 8.526 Log(10)copies/mL, and on-treatment viral load decline was 5.683 Log(10)copies/mL. The median half-life of free virus was 24.89 hours. The median half-life of infected hepatocytes was 7.39 days. The viral decay patterns were visualized as triphasic curves with decreasing slopes over time: fastest decay in the first phase; slowest in the third phase; the second phase in between. CONCLUSIONS: In the present study, mathematical modeling of hepatitis B in patients with virological response and HBsAg decline during 24-week antiviral therapy showed triphasic viral dynamics with direct introduction of immune effectors as a new compartment, which was thought to reflect the reduction of clearance rate of infected cells over time. This modeling method seems more appropriate to describe long-term viral dynamics compared to the biphasic model, and needs further validation.