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1.  Presence of multiple peripheral circadian oscillators in the tissues controlling voiding function in mice 
Circadian clocks are the endogenous oscillators that harmonize a variety of physiological processes within the body. Although many urinary functions exhibit clear daily or circadian variation in diurnal humans and nocturnal rodents, the precise mechanisms of these variations are as yet unclear. In the present study, we demonstrate that Per2 promoter activity clearly oscillates in neonate and adult bladders cultured ex vivo from Per2::Luc knock-in mice. In subsequent experiments, we show that multiple local oscillators are operating in all the bladder tissues (detrusor, sphincter and urothelim) and the lumbar spinal cord (L4–5) but not in the pontine micturition center or the ventrolateral periaqueductal gray of the brain. Accordingly, the water intake and urine volume exhibited daily and circadian variations in young adult wild-type mice but not in Per1−/−Per2−/− mice, suggesting a functional clock-dependent nature of the micturition rhythm. Particularly in PDK mice, the water intake and urinary excretion displayed an arrhythmic pattern under constant darkness, and the amount of water consumed and excreted significantly increased compared with those of WT mice. These results suggest that local circadian clocks reside in three types of bladder tissue and the lumbar spinal cord and may have important roles in the circadian control of micturition function.
PMCID: PMC3972783  PMID: 24603368
bladder; circadian clock; lumbar spinal cord; peripheral oscillator; voiding; water intake
2.  Anti-inflammatory activity of compounds isolated from Astragalus sinicus L. in cytokine-induced keratinocytes and skin 
Inflammation is a part of the complex biological responses of a tissue to injury that protect the organ by removing injurious stimuli and initiating the healing process, and is considered as a mechanism of innate immunity. To identify biologically active compounds against pathogenic inflammatory and immune responses, we fractionated water, aqueous methanol and n-hexane layers from nine kinds of leguminosae and examined anti-inflammatory activity of the fractions in human keratinocytes and mouse skin. Among the fractions, rf3 and rf4, isolated from the aqueous methanol layer of Astragalus sinicus L., exhibited the strongest reactive oxygen species (ROS)-scavenging and anti-inflammatory activities as measured by inhibition of the intracellular ROS production, nuclear factor-kappaB (NF-κB), janus kinase (JAK)/signal transducer and activator of transcription (STAT), and phosphatidylinositol 3-kinase/Akt signaling in cytokine-stimulated human keratinocytes, as well as by effects on T-cell differentiation in mouse CD4+ T cells. In addition, topical application of rf3 and rf4 suppressed the progression of psoriasis-like dermatitis and expression of pro-inflammatory mediators in interleukin (IL)-23-injected mouse ears. Our results suggest that Astragalus sinicus L. may ameliorate chronic inflammatory skin diseases due to its antioxidant and anti-inflammatory activities via regulation of the intracellular ROS production, NF-κB, JAK/STAT and PI3/Akt signaling cascades as well as immune responses, and these results are the first report that Astragalus sinicus L. exhibits pharmacological activity.
PMCID: PMC3972784  PMID: 24651533
Astragalus sinicus L.; immune response; inflammation; JAK/STAT; NF-κB; PI3/Akt
3.  Ribosomal protein mutations in Korean patients with Diamond-Blackfan anemia 
Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome characterized by hypoproliferative anemia, associated physical malformations and a predisposition to cancer. DBA has been associated with mutations and deletions in the large and small ribosomal protein genes, and genetic aberrations have been detected in ∼50–60% of patients. In this study, nine Korean DBA patients were screened for mutations in eight known DBA genes (RPS19, RPS24, RPS17, RPS10, RPS26, RPL35A, RPL5 and RPL11) using the direct sequencing method. Mutations in RPS19, RPS26 and RPS17 were detected in four, two and one patient, respectively. Among the mutations detected in RPS19, two mutations were novel (c.26T>A, c.357-2A>G). For the mutation-negative cases, array-CGH analysis was performed to identify copy-number variations, and no deletions involving the known DBA gene regions were identified. The relative mRNA expression of RPS19 estimated using real-time quantitative PCR analysis revealed two- to fourfold reductions in RPS19 mRNA expression in three patients with RPS19 mutations, and p53 protein expression analysis by immunohistochemistry showed variable but significant nuclear staining in the DBA patients. In conclusion, heterozygous mutations in the known DBA genes RPS19, RPS26 and RPS17 were detected in seven out of nine Korean DBA patients. Among these patients, RPS19 was the most frequently mutated gene. In addition, decreased RPS19 mRNA expression and p53 overexpression were observed in the Korean DBA patients, which supports the hypothesis that haploinsufficiency and p53 hyperactivation represent a central pathway underlying the pathogenesis of DBA.
PMCID: PMC3972785  PMID: 24675553
array-CGH; Diamond-Blackfan anemia; ribosomal protein; sequencing
4.  Antigen targeting to M cells for enhancing the efficacy of mucosal vaccines 
Vaccination is one of the most successful applications of immunology and for a long time has depended on parenteral administration protocols. However, recent studies have pointed to the promise of mucosal vaccination because of its ease, economy and efficiency in inducing an immune response not only systemically, but also in the mucosal compartment where many pathogenic infections are initiated. However, successful mucosal vaccination requires the help of an adjuvant for the efficient delivery of vaccine material into the mucosa and the breaking of the tolerogenic environment, especially in oral mucosal immunization. Given that M cells are the main gateway to take up luminal antigens and initiate antigen-specific immune responses, understanding the role and characteristics of M cells is crucial for the development of successful mucosal vaccines. Especially, particular interest has been focused on the regulation of the tolerogenic mucosal microenvironment and the introduction of the luminal antigen into the lymphoid organ by exploiting the molecules of M cells. Here, we review the characteristics of M cells and the immune regulatory factors in mucosa that can be exploited for mucosal vaccine delivery and mucosal immune regulation.
PMCID: PMC3972786  PMID: 24626171
immunity; M cell; vaccine
5.  Oleuropein prevents the progression of steatohepatitis to hepatic fibrosis induced by a high-fat diet in mice 
Nonalcoholic steatohepatitis (NASH) is characterized by hepatocyte injury and inflammatory cell infiltration, which has been linked to peripheral insulin resistance and increased levels of triglycerides in the liver. The purposes of this study were to establish a mouse model of NASH by feeding mice a 60% high-fat diet (HFD) and to demonstrate the anti-fibrotic effects of oleuropein, which has been shown to have anti-oxidant and anti-inflammatory properties, in this HFD-induced mouse model of NASH. C57BL/6 mice were divided into three groups: a regular diet group (Chow), a HFD group and an oleuropein-supplemented HFD group (OSD), which was fed a 0.05% OSD for 6 months. The effects of oleuropein in this model were evaluated using biochemical, histological and molecular markers. The expression levels of alpha-smooth muscle actin (α-SMA)and collagen type I in the HFD and OSD groups were evaluated using real-time PCR and western blotting. The body weight, biochemical marker levels, nonalcoholic fatty liver disease activity score, homeostasis model of assessment-insulin resistance (HOMA-IR) and leptin levels observed in the HFD group at 9 and 12 months were higher than those observed in the Chow group. The HOMA-IR and leptin levels in the OSD group were decreased compared with the HFD group. In addition, α-SMA and collagen type I expression were decreased by oleuropein treatment. We established a NASH model induced by HFD and demonstrated that this model exhibits the histopathological features of NASH progressing to fibrosis. Our results suggest that oleuropein may be pharmacologically useful in preventing the progression of steatohepatitis and fibrosis and may be a promising agent for the treatment of NASH in humans.
PMCID: PMC3972787
fibrosis; nonalcoholic steatohepatitis; oleuropein
6.  Simultaneous deletion of floxed genes mediated by CaMKIIα-Cre in the brain and in male germ cells: application to conditional and conventional disruption of Goα 
The Cre/LoxP system is a well-established approach to spatially and temporally control genetic inactivation. The calcium/calmodulin-dependent protein kinase II alpha subunit (CaMKIIα) promoter limits expression to specific regions of the forebrain and thus has been utilized for the brain-specific inactivation of the genes. Here, we show that CaMKIIα-Cre can be utilized for simultaneous inactivation of genes in the adult brain and in male germ cells. Double transgenic Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice generated by crossing CaMKIIα-Cre+/Cre mice with floxed ROSA26 lacZ reporter (Rosa26+/stop-lacZ) mice exhibited lacZ expression in the brain and testis. When these mice were mated to wild-type females, about 27% of the offspring were whole body blue by X-gal staining without inheriting the Cre transgene. These results indicate that recombination can occur in the germ cells of male Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice. Similarly, when double transgenic Gnao+/f::CaMKIIα-Cre+/Cre mice carrying a floxed Go-alpha gene (Gnaof/f) were backcrossed to wild-type females, approximately 22% of the offspring carried the disrupted allele (GnaoΔ) without inheriting the Cre transgene. The GnaoΔ/Δ mice closely resembled conventional Go-alpha knockout mice (Gnao−/−) with respect to impairment of their behavior. Thus, we conclude that CaMKIIα-Cre mice afford recombination for both tissue- and time-controlled inactivation of floxed target genes in the brain and for their permanent disruption. This work also emphasizes that extra caution should be exercised in utilizing CaMKIIα-Cre mice as breeding pairs.
PMCID: PMC3972788
brain; Cre; CaMKII alpha; Gnao; testis
7.  Mucosal dendritic cells shape mucosal immunity 
Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases.
PMCID: PMC3972789  PMID: 24626170
antigen capture; helper T-cell subset; mucosal dendritic cells; mucosal vaccine; secretory IgA
8.  Role of histone deacetylase activity in the developing lateral line neuromast of zebrafish larvae 
Histone deacetylases are involved in many biological processes and have roles in regulating cell behaviors such as cell cycle entry, cell proliferation and apoptosis. However, the effect of histone deacetylases on the development of hair cells (HCs) has not been fully elucidated. In this study, we examined the influence of histone deacetylases on the early development of neuromasts in the lateral line of zebrafish. Hair cell development was evaluated by fluorescent immunostaining in the absence or presence of histone deacetylase inhibitors. Our results suggested that pharmacological inhibition of histone deacetylases with inhibitors, including trichostatin A, valproic acid and MS-275, reduced the numbers of both HCs and supporting cells in neuromasts. We also found that the treatment of zebrafish larvae with inhibitors caused accumulation of histone acetylation and suppressed proliferation of neuromast cells. Real-time PCR results showed that the expression of both p21 and p27 mRNA was increased following trichostatin A treatment and the increase in p53 mRNA was modest under the same conditions. However, the expression of p53 mRNA was significantly increased by treatment with a high concentration of trichostatin A. A high concentration of trichostatin A also led to increased cell death in neuromasts as detected in a TUNEL assay. Moreover, the nuclei of most of these pyknotic cells were immunohistochemically positive for cleaved caspase-3. These results suggest that histone deacetylase activity is involved in lateral line development in the zebrafish and might have a role in neuromast formation by altering cell proliferation through the expression of cell cycle regulatory proteins.
PMCID: PMC3972790
hair cell; histone deacetylases; neuromast; supporting cell; zebrafish
9.  Syntenin increases the invasiveness of small cell lung cancer cells by activating p38, AKT, focal adhesion kinase and SP1 
Syntenin is a PDZ domain-containing adaptor protein that has been recently shown to regulate migration and invasion in several tumors. Small cell lung cancer (SCLC) is notorious for its invasiveness and strong potential for metastasis. We therefore studied the influence of syntenin on the invasiveness of SCLC. Immunohistochemistry in tumor tissues showed that syntenin was more frequently expressed in small cell carcinomas than other neuroendocrine tumors, such as carcinoids and neuroblastomas, suggesting that syntenin expression may be related to more aggressive forms of neuroendocrine tumors. In SCLC patients, syntenin overexpression in tumor cells was significantly associated with more extensive and advanced disease at the time of diagnosis (P=0.029). Overexpression of syntenin in SCLC cells that were intrinsically syntenin-low increased the invasiveness of cells and led to the induction of extracellular matrix (ECM)-degrading membrane type 1-matrix metalloproteinase (MT1-MMP) and matrix metalloproteinase 2 (MMP2). In contrast, suppression of syntenin in syntenin-high cells was associated with the downregulation of MT1-MMP. Contrary to the results of previous studies using malignant melanomas and breast carcinomas, signaling cascades were shown to be further transduced through p38 MAPK and PI3K/AKT, with activation of SP1 rather than NF-κB, under circumstances not involving ECM interaction. In addition, the upstream molecule focal adhesion kinase was induced by syntenin activation, in spite of the absence of ECM interaction. These results suggest that syntenin might contribute to the invasiveness of SCLC and could be utilized as a new therapeutic target for controlling invasion and metastasis in SCLC.
PMCID: PMC3972791
MMP; p38 MAPK; PI3K/AKT; small cell lung cancer; syntenin
10.  Quantitative expression and localization of cysteine and aspartic proteases in human abdominal aortic aneurysms 
Cysteine and aspartic proteases possess high elastolytic activity and might contribute to the degradation of the abdominal aortic aneurysm (AAA) wall. The aim of this study was to analyze, in detail, the proteases (cathepsins B, D, K, L and S, and inhibitor cystatin C) found in human AAA and healthy aortic tissue samples. The vessel walls from AAA patients (n=36) and nonaneurysmal aortae (n=10) were retrieved using conventional surgical repair and autopsy methods. Serum samples from the same AAA patients and 10 healthy volunteers were also collected. Quantitative expression analyses were performed at the mRNA level using real-time reverse transcriptase-PCR (RT–PCR). Furthermore, analyses at the protein level included western blot and immunoprecipitation analyses. Cellular sources of cysteine/aspartic proteases and cystatin C were identified by immunohistochemistry (IHC). All cysteine/aspartic proteases and cystatin C were detected in the AAA and control samples. Using quantitative RT–PCR, a significant increase in expression was observed for cathepsins B (P=0.021) and L (P=0.018), compared with the controls. Cathepsin B and cystatin C were also detected in the serum of AAA patients. Using IHC, smooth muscle cells (SMCs) and macrophages were positive for all of the tested cathepsins, as well as cystatin C; in addition, the lymphocytes were mainly positive for cathepsin B, followed by cathepsins D and S. All cysteine/aspartic proteases analyzed in our study were detected in the AAA and healthy aorta. The highest expression was found in macrophages and SMCs. Consequently, cysteine/aspartic proteases might play a substantial role in AAA.
PMCID: PMC3972792
abdominal aortic aneurysms; cysteine and aspartic proteases; degradation of extracellular matrix
11.  Recent progress in mucosal immunology and vaccine development 
PMCID: PMC3972793  PMID: 24626172
12.  Regulatory T-cell vaccination independent of auto-antigen 
To date, efforts to treat autoimmune diseases have primarily focused on the disease symptoms rather than on the cause of the disease. In large part, this is attributed to not knowing the responsible auto-antigens (auto-Ags) for driving the self-reactivity coupled with the poor success of treating autoimmune diseases using oral tolerance methods. Nonetheless, if tolerogenic approaches or methods that stimulate regulatory T (Treg) cells can be devised, these could subdue autoimmune diseases. To forward such efforts, our approach with colonization factor antigen I (CFA/I) fimbriae is to establish bystander immunity to ultimately drive the development of auto-Ag-specific Treg cells. Using an attenuated Salmonella vaccine expressing CFA/I fimbriae, fimbriae-specific Treg cells were induced without compromising the vaccine's capacity to protect against travelers' diarrhea or salmonellosis. By adapting the vaccine's anti-inflammatory properties, it was found that it could also dampen experimental inflammatory diseases resembling multiple sclerosis (MS) and rheumatoid arthritis. Because of this bystander effect, disease-specific Treg cells are eventually induced to resolve disease. Interestingly, this same vaccine could elicit the required Treg cell subset for each disease. For MS-like disease, conventional CD25+ Treg cells are stimulated, but for arthritis CD39+ Treg cells are induced instead. This review article will examine the potential of treating autoimmune diseases without having previous knowledge of the auto-Ag using an innocuous antigen to stimulate Treg cells via the production of transforming growth factor-β and interleukin-10.
PMCID: PMC3972794  PMID: 24626168
autoimmunity; bacteria; fimbriae; mucosal immunity; regulatory T cells; vaccine
13.  β1-integrin-dependent migration of microglia in response to neuron-released α-synuclein 
Chronic neuroinflammation is an integral pathological feature of major neurodegenerative diseases. The recruitment of microglia to affected brain regions and the activation of these cells are the major events leading to disease-associated neuroinflammation. In a previous study, we showed that neuron-released α-synuclein can activate microglia through activating the Toll-like receptor 2 (TLR2) pathway, resulting in proinflammatory responses. However, it is not clear whether other signaling pathways are involved in the migration and activation of microglia in response to neuron-released α-synuclein. In the current study, we demonstrated that TLR2 activation is not sufficient for all of the changes manifested by microglia in response to neuron-released α-synuclein. Specifically, the migration of and morphological changes in microglia, triggered by neuron-released α-synuclein, did not require the activation of TLR2, whereas increased proliferation and production of cytokines were strictly under the control of TLR2. Construction of a hypothetical signaling network using computational tools and experimental validation with various peptide inhibitors showed that β1-integrin was necessary for both the morphological changes and the migration. However, neither proliferation nor cytokine production by microglia was dependent on the activation of β1-integrin. These results suggest that β1-integrin signaling is specifically responsible for the recruitment of microglia to the disease-affected brain regions, where neurons most likely release relatively high levels of α-synuclein.
PMCID: PMC3972795
α-synuclein; β1-integrin; microglial migration; neuroinflammation; Parkinson's disease
14.  New era for mucosal mast cells: their roles in inflammation, allergic immune responses and adjuvant development 
To achieve immune homeostasis in such a harsh environment as the intestinal mucosa, both active and quiescent immunity operate simultaneously. Disruption of gut immune homeostasis leads to the development of intestinal immune diseases such as colitis and food allergies. Among various intestinal innate immune cells, mast cells (MCs) play critical roles in protective immunity against pathogenic microorganisms, especially at mucosal sites. This suggests the potential for a novel MC-targeting type of vaccine adjuvant. Dysregulated activation of MCs also results in inflammatory responses in mucosal compartments. The regulation of this yin and yang function of MCs remains to be elucidated. In this review, we focus on the roles of mucosal MCs in the regulation of intestinal allergic reaction, inflammation and their potential as a new target for the development of mucosal adjuvants.
PMCID: PMC3972796  PMID: 24626169
food allergy; intestinal inflammation; mucosal mast cells
15.  Increased expression of the receptor for advanced glycation end products in neurons and astrocytes in a triple transgenic mouse model of Alzheimer's disease 
The receptor for advanced glycation end products (RAGE) has been reported to have a pivotal role in the pathogenesis of Alzheimer's disease (AD). This study investigated RAGE levels in the hippocampus and cortex of a triple transgenic mouse model of AD (3xTg-AD) using western blotting and immunohistochemical double-labeling to assess cellular localization. Analysis of western blots showed that there were no differences in the hippocampal and cortical RAGE levels in 10-month-old adult 3xTg-AD mice, but significant increases in RAGE expression were found in the 22- to 24-month-old aged 3xTg-AD mice compared with those of age-matched controls. RAGE-positive immunoreactivity was observed primarily in neurons of aged 3xTg-AD mice with very little labeling in non-neuronal cells, with the notable exception of RAGE presence in astrocytes in the hippocampal area CA1. In addition, RAGE signals were co-localized with the intracellular amyloid precursor protein (APP)/amyloid beta (Aβ) but not with the extracellular APP/Aβ. In aged 3xTg-AD mice, expression of human tau was observed in the hippocampal area CA1 and co-localized with RAGE signals. The increased presence of RAGE in the 3xTg-AD animal model showing critical aspects of AD neuropathology indicates that RAGE may contribute to cellular dysfunction in the AD brain.
PMCID: PMC3944440  PMID: 24503708
Alzheimer's disease; astrocyte; cortex; hippocampus; mice; receptor for advanced glycation end products (RAGE)
16.  Increased expression of the receptor for advanced glycation end products in neurons and astrocytes in a triple transgenic mouse model of Alzheimer's disease 
The receptor for advanced glycation end products (RAGE) has been reported to have a pivotal role in the pathogenesis of Alzheimer's disease (AD). This study investigated RAGE levels in the hippocampus and cortex of a triple transgenic mouse model of AD (3xTg-AD) using western blotting and immunohistochemical double-labeling to assess cellular localization. Analysis of western blots showed that there were no differences in the hippocampal and cortical RAGE levels in 10-month-old adult 3xTg-AD mice, but significant increases in RAGE expression were found in the 22- to 24-month-old aged 3xTg-AD mice compared with those of age-matched controls. RAGE-positive immunoreactivity was observed primarily in neurons of aged 3xTg-AD mice with very little labeling in non-neuronal cells, with the notable exception of RAGE presence in astrocytes in the hippocampal area CA1. In addition, RAGE signals were co-localized with the intracellular amyloid precursor protein (APP)/amyloid beta (Aβ) but not with the extracellular APP/Aβ. In aged 3xTg-AD mice, expression of human tau was observed in the hippocampal area CA1 and co-localized with RAGE signals. The increased presence of RAGE in the 3xTg-AD animal model showing critical aspects of AD neuropathology indicates that RAGE may contribute to cellular dysfunction in the AD brain.
PMCID: PMC3909893  PMID: 24503708
Alzheimer's disease; astrocyte; cortex; hippocampus; mice; receptor for advanced glycation end products (RAGE)
17.  Transactivation of bad by vorinostat-induced acetylated p53 enhances doxorubicin-induced cytotoxicity in cervical cancer cells 
Vorinostat (VOR) has been reported to enhance the cytotoxic effects of doxorubicin (DOX) with fewer side effects because of the lower DOX dosage in breast cancer cells. In this study, we investigated the novel mechanism underlying the synergistic cytotoxic effects of VOR and DOX co-treatment in cervical cancer cells HeLa, CaSki and SiHa cells. Co-treatment with VOR and DOX at marginal doses led to the induction of apoptosis through caspase-3 activation, poly (ADP-ribose) polymerase cleavage and DNA micronuclei. Notably, the synergistic growth inhibition induced by the co-treatment was attributed to the upregulation of the pro-apoptotic protein Bad, as the silencing of Bad expression using small interfering RNA (siRNA) abolished the phenomenon. As siRNA against p53 did not result in an increase in acetylated p53 and the consequent upregulation of Bad, the observed Bad upregulation was mediated by acetylated p53. Moreover, a chromatin immunoprecipitation analysis showed that the co-treatment of HeLa cells with VOR and DOX increased the recruitment of acetylated p53 to the bad promoter, with consequent bad transactivation. Conversely, C33A cervical cancer cells containing mutant p53 co-treated with VOR and DOX did not exhibit Bad upregulation, acetylated p53 induction or consequent synergistic growth inhibition. Together, the synergistic growth inhibition of cervical cancer cell lines induced by co-treatment with VOR and DOX can be attributed to the upregulation of Bad, which is induced by acetylated p53. These results show for the first time that the acetylation of p53, rather than histones, is a mechanism for the synergistic growth inhibition induced by VOR and DOX co-treatments.
PMCID: PMC3944441  PMID: 24525822
bad; cervical cancer cell; doxorubicin; p53 acetylation; vorinostat
18.  Knockdown of 14-3-3ζ enhances radiosensitivity and radio-induced apoptosis in CD133+ liver cancer stem cells 
14-3-3ζ is related to many cancer survival cellular processes. In a previous study, we showed that silencing 14-3-3ζ decreases the resistance of hepatocellular carcinoma (HCC) to chemotherapy. In this study, we investigated whether silencing 14-3-3ζ affects the radioresistance of cancer stem-like cells (CSCs) in HCC. Knockdown of 14-3-3ζ decreased cell viability and the number of spheres by reducing radioresistance in CSCs after γ-irradiation (IR). Furthermore, the levels of pro-apoptotic proteins were upregulated in CSCs via silencing 14-3-3ζ after IR. These results suggest that 14-3-3ζ knockdown enhances radio-induced apoptosis by reducing radioresistance in liver CSCs.
PMCID: PMC3944442  PMID: 24556826
14-3-3ζ; apoptosis; cancer stem-like cell; hepatocellular carcinoma; radioresistance
19.  MicroRNA-21 controls the development of osteoarthritis by targeting GDF-5 in chondrocytes 
Osteoarthritis is a common cause of functional deterioration in older adults and is an immense burden on the aging population. Altered chondrogenesis is the most important pathophysiological process involved in the development of osteoarthritis. However, the molecular mechanism underlying the regulation of chondrogenesis in patients with osteoarthritis requires further elucidation, particularly with respect to the role of microRNAs. MiR-21 expression in cartilage specimens was examined in 10 patients with knee osteoarthritis and 10 traumatic amputees. The effect of miR-21 on chondrogenesis was also investigated in a chondrocyte cell line. The effect of miR-21 on the expression of growth differentiation factor 5 (GDF-5) was further assessed by luciferase reporter assay and western blot. We found that endogenous miR-21 is upregulated in osteoarthritis patients, and overexpression of miR-21 could attenuate the process of chondrogenesis. Furthermore, we identified GDF-5 as the direct target of miR-21 during the regulation of chondrogenesis. Our data suggest that miR-21 has an important role in the pathogenesis of osteoarthritis and is a potential therapeutic target.
PMCID: PMC3944443  PMID: 24577233
chondrogenesis; GDF-5; miR-21; osteoarthritis
20.  Tetraspanin CD9 modulates ADAM17-mediated shedding of LR11 in leukocytes 
LR11, also known as SorLA or SORL1, is a type-I membrane protein from which a large extracellular part, soluble LR11 (sLR11), is released by proteolytic shedding on cleavage with a disintegrin and metalloproteinase 17 (ADAM17). A shedding mechanism is presumed to have a key role in the functions of LR11, but the evidence for this has not yet been demonstrated. Tetraspanin CD9 has been recently shown to regulate the ADAM17-mediated shedding of tumor necrosis factor-α and intercellular adhesion molecule-1 on the cell surface. Here, we investigated the role of CD9 on the shedding of LR11 in leukocytes. LR11 was not expressed in THP-1 monocytes, but it was expressed and released in phorbol 12-myristate 13-acetate (PMA)-induced THP-1 macrophages (PMA/THP-1). Confocal microscopy showed colocalization of LR11 and CD9 proteins on the cell surface of PMA/THP-1. Ectopic neo-expression of CD9 in CCRF-SB cells, which are LR11-positive and CD9-negative, reduced the amount of sLR11 released from the cells. In contrast, incubation of LR11-transfected THP-1 cells with neutralizing anti-CD9 monoclonal antibodies increased the amount of sLR11 released from the cells. Likewise, the PMA-stimulated release of sLR11 increased in THP-1 cells transfected with CD9-targeted shRNAs, which was negated by treatment with the metalloproteinase inhibitor GM6001. These results suggest that the tetraspanin CD9 modulates the ADAM17-mediated shedding of LR11 in various leukemia cell lines and that the association between LR11 and CD9 on the cell surface has an important role in the ADAM17-mediated shedding mechanism.
PMCID: PMC3944444
ADAM17; CD9; LR11; TNF-α converting enzyme; Tetraspanin
21.  Recent advance in brown adipose physiology and its therapeutic potential 
Brown adipose tissue (BAT) is a specialized thermoregulatory organ that has a critical role in the regulation of energy metabolism. Specifically, energy expenditure can be enhanced by the activation of BAT function and the induction of a BAT-like catabolic phenotype in white adipose tissue (WAT). Since the recent recognition of metabolically active BAT in adult humans, BAT has been extensively studied as one of the most promising targets identified for treating obesity and its related disorders. In this review, we summarize information on the developmental origin of BAT and the progenitors of brown adipocytes in WAT. We explore the transcriptional control of brown adipocyte differentiation during classical BAT development and in WAT browning. We also discuss the neuronal control of BAT activity and summarize the recently identified non-canonical stimulators of BAT that can act independently of β-adrenergic stimulation. Finally, we review new findings on the beneficial effects of BAT activation and development with respect to improving metabolic profiles. We highlight the therapeutic potential of BAT and its future prospects, including pharmacological intervention and cell-based therapies designed to enhance BAT activity and development.
PMCID: PMC3944445  PMID: 24556827
brown adipose tissue (BAT); obesity; progenitors; white adipose tissue (WAT)
22.  Heptachlor induced nigral dopaminergic neuronal loss and Parkinsonism-like movement deficits in mice 
Epidemiological studies have suggested an association between pesticide exposure and Parkinson's disease. In this study, we examined the neurotoxicity of an organochlorine pesticide, heptachlor, in vitro and in vivo. In cultured SH-SY5Y cells, heptachlor induced mitochondria-mediated apoptosis. When injected into mice intraperitoneally on a subchronic schedule, heptachlor induced selective loss of dopaminergic neurons in the substantia nigra pars compacta. In addition, the heptachlor injection induced gliosis of microglia and astrocytes selectively in the ventral midbrain area. When the general locomotor activities were monitored by open field test, the heptachlor injection did not induce any gross motor dysfunction. However, the compound induced Parkinsonism-like movement deficits when assessed by a gait and a pole test. These results suggest that heptachlor can induce Parkinson's disease-related neurotoxicities in vivo.
PMCID: PMC3944446  PMID: 24577234
apoptosis; dopaminergic neuron; heptachlor; mitochondria; organochlorine; Parkinson's disease
23.  Mesenchymal stem cells reciprocally regulate the M1/M2 balance in mouse bone marrow-derived macrophages 
Mesenchymal stem cells (MSCs) have been widely studied for their applications in stem cell-based regeneration. During myocardial infarction (MI), infiltrated macrophages have pivotal roles in inflammation, angiogenesis and cardiac remodeling. We hypothesized that MSCs may modulate the immunologic environment to accelerate regeneration. This study was designed to assess the functional relationship between the macrophage phenotype and MSCs. MSCs isolated from bone marrow and bone marrow-derived macrophages (BMDMs) underwent differentiation induced by macrophage colony-stimulating factor. To determine the macrophage phenotype, classical M1 markers and alternative M2 markers were analyzed with or without co-culturing with MSCs in a transwell system. For animal studies, MI was induced by the ligation of the rat coronary artery. MSCs were injected within the infarct myocardium, and we analyzed the phenotype of the infiltrated macrophages by immunostaining. In the MSC-injected myocardium, the macrophages adjacent to the MSCs showed strong expression of arginase-1 (Arg1), an M2 marker. In BMDMs co-cultured with MSCs, the M1 markers such as interleukin-6 (IL-6), IL-1β, monocyte chemoattractant protein-1 and inducible nitric oxide synthase (iNOS) were significantly reduced. In contrast, the M2 markers such as IL-10, IL-4, CD206 and Arg1 were markedly increased by co-culturing with MSCs. Specifically, the ratio of iNOS to Arg1 in BMDMs was notably downregulated by co-culturing with MSCs. These results suggest that the preferential shift of the macrophage phenotype from M1 to M2 may be related to the immune-modulating characteristics of MSCs that contribute to cardiac repair.
PMCID: PMC3909888  PMID: 24406319
immunologic environment; macrophage; mesenchymal stem cell; myocardial infarction
24.  Exogenous rhTRX reduces lipid accumulation under LPS-induced inflammation 
Redox-regulating molecule, recombinant human thioredoxin (rhTRX) which shows anti-inflammatory, and anti-oxidative effects against lipopolysaccharide (LPS)-stimulated inflammation and regulate protein expression levels. LPS-induced reactive oxygen intermediates (ROI) and NO production were inhibited by exogenous rhTRX. We identified up/downregulated intracellular proteins under the LPS-treated condition in exogenous rhTRX-treated A375 cells compared with non-LPS-treated cells via 2-DE proteomic analysis. Also, we quantitatively measured cytokines of in vivo mouse inflammation models using cytometry bead array. Exogenous rhTRX inhibited LPS-stimulated production of ROI and NO levels. TIP47 and ATP synthase may influence the inflammation-related lipid accumulation by affecting lipid metabolism. The modulation of skin redox environments during inflammation is most likely to prevent alterations in lipid metabolism through upregulation of TIP47 and ATP synthase and downregulation of inflammatory cytokines. Our results demonstrate that exogenous rhTRX has anti-inflammatory properties and intracellular regulatory activity in vivo and in vitro. Monitoring of LPS-stimulated pro-inflammatory conditions treated with rhTRX in A375 cells could be useful for diagnosis and follow-up of inflammation reduction related with candidate proteins. These results have a therapeutic role in skin inflammation therapy.
PMCID: PMC3909889  PMID: 24406320
inflammation; lipid accumulation; rhTRX; skin cell proteomics; TIP47
25.  The role of adiponectin in the production of IL-6, IL-8, VEGF and MMPs in human endothelial cells and osteoblasts: implications for arthritic joints 
This study was performed to evaluate the contribution of adiponectin to the production of interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and MMP-13 in human endothelial cells and osteoblasts in arthritic joints. Cultured human umbilical vascular endothelial cells (HUVECs) and osteoblasts were stimulated with adiponectin (1 or 10 μg ml−1) or IL-1β (0.1 ng ml−1) in the presence or absence of hypoxia for 24 h. The protein expression patterns were examined by analyzing culture supernatants using the enzyme-linked immunosorbent assay (ELISA). Adiponectin significantly stimulated the production of VEGF, MMP-1 and MMP-13 in osteoblasts but not in endothelial cells, whereas it significantly stimulated the production of IL-6 and IL-8 in both endothelial cells and osteoblasts. The increase in VEGF production induced by adiponectin was significantly greater than that induced by IL-1β. The production of IL-6 and IL-8 in adiponectin-stimulated endothelial cells was approximately 10-fold higher than that in IL-1β-stimulated endothelial cells; in osteoblasts, adiponectin-induced IL-6 and IL-8 secretion was approximately twofold higher than that induced by IL-1β. In addition, IL-8 production in endothelial cells was approximately sevenfold higher than in osteoblasts. However, IL-6 levels were similar between the two cell types, suggesting that adiponectin may be involved in the production of IL-8 in endothelial cells, which may have an important role in neutrophil recruitment to arthritic joints. Furthermore, the increases in protein expression induced by adiponectin were differentially regulated by hypoxia. In conclusion, adiponectin has a more important role than does IL-1β in the production of mediators that drive synovitis and joint destruction in endothelial cells and osteoblasts at physiological concentrations.
PMCID: PMC3909890  PMID: 24434628
adiponectin; cytokines and inflammatory mediators; endothelium; osteoblast; rheumatoid arthritis

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