AfMkk2 is required for cell wall integrity signaling,adhesion, and full virulence of the human pathogen Aspergillus fumigatus

The cell wall integrity (CWI) pathway, best characterized in S. cerevisiae, is strikingly conserved in Aspergillus species. We analyzed the importance of AfMkk2, a CWI signaling kinase, for virulence and antifungal therapy in the human pathogen A. fumigatus. A mutant lacking AfMkk2 is less adherent to glass and plastic surfaces and shows increased sensitivity to alkaline pH stress and antifungals. Rather than AfMpkA, the target kinase of AfMkk2, AfMpkB is activated in the mutant under cell wall stress. Interestingly, the mutant lacking AfMkk2 shows an enhanced sensitivity to posaconazole and voriconazole. And in agreement with its sensitivity to moderate temperatures, it is less virulent in a murine infection model. Our data underline the importance of mkk2 for the fitness, but also for the pathogenicity of A. fumigatus.     

PRRX2通过调控Wnt/β-catenin信号通路促进胃癌细胞活力和迁移

目的:研究配对相关同源框2(paired-related homeobox 2,PRRX2)基因对胃癌细胞活力和迁移能力的影响,并分析其调控Wnt/β-catenin信号通路的机制。方法:通过生物信息学分析在线数据库中胃癌和正常胃组织的PRRX2表达水平及PRRX2在胃癌组织中的表达与胃癌患者总生存率的相关性;将PRRX2小干扰RNA(si RNA)和过表达质粒分别转染到胃癌细胞MGC-803和SGC-7901中,敲低和过表达PRRX2基因;MTT法和Transwell实验检测胃癌细胞的活力和迁移能力;Western blot和TOPflash/FOPflash双萤光素酶报告基因实验检测Wnt/β-catenin信号通路的活化情况;免疫共沉淀实验检测PRRX2与β-catenin蛋白的相互作用。结果:敲低PRRX2能够减弱胃癌细胞MGC-803的活力和迁移能力(P0.05)。过表达PRRX2能够增强胃癌细胞SGC-7901的活力和迁移能力(P0.05),增加β-catenin、c-Myc和cyclin D1的蛋白的表达水平(P0.05),增强TOPflash/FOPflash双萤光素酶报告基因活性(P0.05)。PRRX2与β-catenin蛋白存在相互作用。结论:PRRX2可促进胃癌细胞的活力和迁移,其机制可能与Wnt/β-catenin信号通路有关。     

Curcumin protects human chondrocytes from IL-1β-induced inhibition of collagen type II and β1-integrin expression and activation of caspase-3: An immunomorphological study

Interleukin 1β (IL-1β) is a pleiotropic pro-inflammatory cytokine that plays a key role in mediating cartilage degradation in osteoarticular disorders such as osteoarthritis (OA) and rheumatoid arthritis (RA). At the cellular level, IL-1β activates matrix degrading enzymes, down-regulates expression of matrix components and induces chondrocyte apoptosis. Curcumin (diferuloylmethane) is an anti-inflammatory phytochemical agent that has recently been shown to antagonize the pro-inflammatory effects of cytokines in chondrocytes and other cells. To test the hypothesis that curcumin also protects chondrocytes from morphological alterations induced by IL-1β, we investigated its in vitro effects on apoptotic signalling proteins and key cartilage-specific matrix components in IL-1β-stimulated chondrocytes.

Human articular chondrocytes were pre-treated with 10 ng/ml IL-1β alone for 30 min before being co-treated with IL-1β and 50 μM curcumin for 5, 15 or 30 min, respectively. The ultrastructural morphology of chondrocytes was investigated by transmission electron microscopy. The production of collagen type II, the adhesion and signal transduction receptor β1-integrin, the apoptosis marker activated caspase-3 was analysed by immunohistochemistry, immunoelectron microscopy and Western blotting.

Transmission electron microscopy of chondrocytes stimulated with IL-1β revealed early degenerative changes which were relieved by curcumin co-treatment. The suppression of collagen type II and β1-integrin synthesis by IL-1β was inhibited by curcumin. Additionally, curcumin antagonized IL-1β-induced caspase-3 activation in a time-dependent manner.

This study clearly demonstrates that curcumin exerts anti-apoptotic and anti-catabolic effects on IL-1β-stimulated articular chondrocytes. Therefore curcumin may have novel therapeutic potential as an adjunct nutraceutical chondroprotective agent for treating OA and related osteoarticular disorders.     

β-雌二醇经ERβ-ERK1/2雌激素胞膜信号传导途径促进肺癌A549细胞迁移和侵袭

目的:研究β-雌二醇(β-estradiol)促进肺癌A549细胞迁移和侵袭的调控机制。方法:体外培养乳腺癌MCF-7细胞和肺癌A549细胞,以MCF-7细胞作为阳性对照明确雌激素受体(ER)在A549细胞中的表达情况; real-time PCR检测ERβ亚型ERβ1、ERβ2和ERβ5在A549细胞中的表达情况,免疫荧光定位ERβ在细胞内的胞膜和胞核分布情况;予β-estradiol刺激A549细胞,Western blot检测胞内ERK1/2磷酸化水平改变,Transwell小室侵袭实验和细胞实时监测培养系统检测细胞迁移和侵袭能力的变化;利用ERK1/2抑制剂PD98059预先处理,Transwell小室侵袭实验和细胞实时监测培养系统检测β-estradiol刺激后细胞迁移和侵袭能力的变化。结果:ER在A549细胞中以表达ERβ为主,且表达的ERβ以ERβ2和ERβ5为主,免疫荧光显示细胞内ERβ以胞质分布为主。β-estradiol可以引起A549细胞ERK1/2磷酸化水平的增加,并促进细胞的迁移和侵袭,抑制ERK1/2信号传导可以逆转β-estradiol促进的细胞迁移和侵袭。结论:β-estradiol经ERβ活化ERK1/2雌激素胞膜信号传导,从而促进A549细胞的侵袭和转移。ERK1/2是ERβ雌激素胞膜信号传导中与肺癌侵袭和转移相关的重要信号节点。     

The concentration-dependent effect of anethole on collagen,MMP-2 and GAG in human skin fibroblast cultures

PurposeIn aging skin and some skin disorders, components of skin extracellular matrix (ECM) are disturbed and therefore research to find skin drugs is important. Evaluation of anethole impact on collagen, GAGs and MMP-2 in human skin fibroblasts was the aim of this study.Materials and methodsFor collagen assay the Sircol dye, 5-[³H]proline and real time-PCR were used. MMP-2 activity was detected by zymography. GAG concentration was determined using 1,9-dimethylmethylene blue (DMMB). Cell viability was assayed with MTT.ResultsIn cells treated with 1 and 10 μM anethole, a significant increase in collagen synthesis was demonstrated. In contrast, collagen synthesis was significantly decreased in cells exposed to 100 μM anethole. Similar alterations were found in collagen type I expression. The concentration of collagen secreted into the medium was higher only in cells exposed to 1 μM anethole, while it was lower under the influence of higher compound concentrations. It may be due to the lack of pro-MMP-2 activation at 1 μM and a significant increase in the level of MMP-2 at 10 and 100 μM anethole. GAG concentration was reduced under the influence of 100 μM anethole, whereas anethole at lower concentrations revealed the ability to prevent H₂O₂-induced GAG increase. No significant cytotoxicity of anethole to fibroblasts was noted.ConclusionsOur findings demonstrate the concentration-dependent action of anethole on the crucial components of ECM in cultured skin fibroblasts, which may be somewhat beneficial and may possibly be developed towards a therapeutic use in some skin disorders.     

Synergy between IL-6 and soluble IL-6 receptor enhances bone morphogenetic protein-2/absorbable collagen sponge-induced bone regeneration via regulation of BMPRIA distribution and degradation

Bone morphogenetic protein-2/absorbable collagen sponge (BMP-2/ACS) implants have been approved for clinical use to induce bone regeneration. We previously showed that exaggerated inflammation characterized by elevated level of inflammatory cytokines including TNF-α, IL-1β, and IL-6 has been shown to inhibit BMP-2/ACS-induced bone regeneration. Furthermore, unlike the negative effects of TNF-α and IL-1β, IL-6 seemed not to affect BMP-2-induced osteoblastic differentiation of bone marrow mesenchymal stem cells (BMSCs). We hypothesized that there may be a regulatory loop between IL-6 and BMP-2 singling to affect BMP-2/ACS-induced bone regeneration. Here, we established a BMP-2/ACS-induced ectopic bone formation model in rats and fund that IL-6 injection significantly increased BMP-2/ACS-induced bone mass. Consistent with this animal model, an in vitro study demonstrated that synergy between IL-6 and soluble IL-6 receptor (IL-6/sIL-6R) promotes BMP-2-induced osteoblastic differentiation of human BMSCs through amplification of BMP/Smad signaling. Strikingly, IL-6 injection did not activate osteoclast-mediated bone resorption in the ectopic bone formation model, and IL-6/sIL-6R treatment did not affect receptor activator of NF-κB ligand (RANKL)-induced osteoclastic differentiation of human peripheral blood mononuclear cells (PBMCs) in vitro. Furthermore, IL-6/sIL-6R treatment did not affect expression of BMP receptors, but enhanced the cell surface translocation of BMP receptor IA (BMPRIA) and inhibited the degradation of BMPRIA. Collectively, these findings indicate that synergy between IL-6 and sIL-6R promotes the cell surface translocation of BMPRIA and maintains the stability of BMPRIA expression, leading to enhanced BMP-2/ACS-induced bone regeneration.     

The effects of acellular amniotic membrane matrix on osteogenic differentiation and ERK1/2 signaling in human dental apical papilla cells

The amniotic membrane (AM) has been widely used in the field of tissue engineering because of the favorable biological properties for scaffolding material. However, little is known about the effects of an acellular AM matrix on the osteogenic differentiation of mesenchymal stem cells. In this study, it was found that both basement membrane side and collagenous stroma side of the acellular AM matrix were capable of providing a preferential environment for driving the osteogenic differentiation of human dental apical papilla cells (APCs) with proven stem cell characteristics. Acellular AM matrix potentiated the induction effect of osteogenic supplements (OS) such as ascorbic acid, β-glycerophosphate, and dexamethasone and enhanced the osteogenic differentiation of APCs, as seen by increased core-binding factor alpha 1 (Cbfa-1) phosphorylation, alkaline phosphatase activity, mRNA expression of osteogenic marker genes, and mineralized matrix deposition. Even in the absence of soluble OS, acellular AM matrix also could exert the substrate-induced effect on initiating APCs’ differentiation. Especially, the collagenous stroma side was more effective than the basement membrane side. Moreover, the AM-induced effect was significantly inhibited by U0126, an inhibitor of extracellular signaling-regulated kinase 1/2 (ERK1/2) signaling. Taken together, the osteogenic differentiation promoting effect on APCs is AM-specific, which provides potential applications of acellular AM matrix in bone/tooth tissue engineering.     

Low‐level laser therapy (780 nm) combined with collagen sponge scaffold promotes repair of rat cranial critical‐size defects and increases TGF‐β, FGF‐2, OPG/RANK and osteocalcin expression

The aim of this study was to evaluate the effect of collagen sponge scaffold (CSS) implantation associated with low‐level laser therapy (LLLT) on repairing bone defects. A single 5‐mm cranial defect was surgically created in forty Wistar rats, which then received one of the following four interventions (n = 10 per group): no treatment (G0); bone defect implanted with collagen sponge scaffold (CSS) alone (G1); defect treated with low‐level laser therapy (LLLT) (wavelength 780 nm; total energy density 120 J/cm²; power 50 mW) alone (G2); and CSS associated with LLLT treatment (G3). After surgery, animals in each group were euthanized at 21 days and 30 days (n = 5 per euthanasia time group). Bone formation was monitored by X‐ray imaging analysis. Biopsies were collected and processed for histological analysis and immunohistochemical evaluation of transforming growth factor‐beta (TGF‐β), fibroblast growth factor‐2 (FGF‐2), osteoprotegerin (OPG) and receptor activator of nuclear factor ? (RANK). Osteocalcin (OCN) was detected by immunofluorescence analysis. Compared to the G0 group, defects in the 30‐day G3 group exhibited increased bone formation, both by increase in radiopaque areas (P < 0.01) and by histomorphometric analysis (P < 0.001). The histopathological analysis showed a decreased number of inflammatory cells (P < 0.001). The combined CCS + LLLT (G3) treatment also resulted in the most intense immunostaining for OPG, RANK, FGF‐2 and TGF‐β, and the most intense and diffuse OCN immunofluorescent labelling at 30 days postsurgery (G3 vs. G0 group, P < 0.05). Therefore, the use of CCS associated with LLLT could offer a synergistic advantage in improving the healing of bone fractures.     

The protein kinase C inhibitor,H7, inhibits tumor cell invasion and metastasis in mouse melanoma via suppression of ERK1/2

Protein kinase C (PKC) has been shown to be a signal transducer during tumorigenesis, tumor cell invasion, and metastasis. Recent studies have reported that the PKC inhibitor, 7-hydroxystaurosporine, inhibits tumor cell invasion. However, the molecular mechanisms of this inhibition of invasion and metastasis are not well understood. In the present study, we attempt to clarify the mechanism by which H7, a PKC inhibitor, inhibits tumor cell invasion and metastasis in the melanoma cell line B16BL6. It was found that H7 inhibits B16BL6 cell invasion and metastasis. We also observed that H7 inhibits the mRNA expression and protein activities of matrix metalloproteinase (MMP)-1, -2, -9 and MT1-MMP. Furthermore, H7 suppresses phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2). However, other signal transduction factors, such as p38 mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase 1/2 (JNK1/2), were unaffected. Moreover, U0126, a MEK1/2 inhibitor, also inhibited B16BL6 cell invasion and metastasis, as well as the mRNA expression and protein activities of MMP-1, -2, -9 and MT1-MMP. This indicates that H7 inhibits signal transduction through the PKC/MEK/ERK pathway, thereby inhibiting B16BL6 cell invasion and metastasis. These results suggest that PKC inhibitors have potential clinical applications in the treatment of tumor cell metastasis.     

The association of ERAP1 and ERAP2 single nucleotide polymorphisms and their haplotypes with psoriasis vulgaris is dependent on the presence or absence of the HLA-C*06:02 allele and age at disease onset

The aim of this case-control study was to elucidate the role of some single nucleotide polymorphisms (SNPs) in the ERAP1 (rs27524, rs27044, rs30187, rs2287987 and rs26653) and ERAP2 (rs2248374) genes in predicting the risk for psoriasis vulgaris in the Polish population. ERAP1, ERAP2 and HLA-C*06:02 typing was done using the TaqMan SNP genotyping assays. We confirmed a strong association of the HLA-C*06:02 allele with early-onset psoriasis. In ERAP1, rs30187T increased the risk of psoriasis in HLA-C*06:02-positive patients, most strongly in late onset psoriasis, whereas it was protective when the HLA-C*06:02 allele was absent. We also found a protective effect of the ERAP2 rs2248374A allele and rs2248374AA genotype only in HLA-C*06:02 carriers, especially in the subgroup of patients with juvenile psoriasis. Analysis of combined haplotypes for ERAP1 and ERAP2 also revealed differences when the patients and controls were stratified by HLA-C*06:02. An ERAP1 haplotype known to possess high enzymatic activity was associated with psoriasis if HLA-C*06:02 was present and a functional ERAP2 allele was absent. In the absence of HLA-C*06:02, an ERAP1 haplotype of low activity was conducive to psoriasis if a functional ERAP2 allele was present, but the same ERAP1 haplotype was protective if the ERAP2 allele was defective.     

The effects of IL‐2 and Treg cells on dendritic cell homeostasis are mediated indirectly via activation of conventional T cells

DC homeostasis is influenced by multiple factors, including the availability of GM‐CSF and Flt3L, both of which exert positive effects on DC differentiation and survival. IL‐2 and Treg cells have recently been proposed as negative regulators of DC numbers. It remains unclear whether their effects in immunosufficient mice are direct, or are mediated via activation of conventional T cells in response to deficiencies of IL‐2 and/or Treg cells. Using a number of in vivo models, we have assessed the role of IL‐2 and Treg‐cell number on conventional splenic and LN DCs. We have found no evidence for a direct role of IL‐2 or Treg cells in negatively regulating DC number. Our data indicate that the expansion of DCs in the absence of either IL‐2 or Treg cells is an indirect effect secondary to the activation and proliferation of conventional T cells.     

The effect of leukocyte-platelet-rich fibrin on bone morphogenetic protein-2 and insulin-like growth factor-1 levels in patients with chronic periodontitis: a randomized split mouth clinical trail

The present study evaluates the effects of leukocyte-platelet-rich fibrin (L-PRF) combined with open flap debridement (OFD) on clinical parameters and growth factors levels (GFL) in chronic periodontitis (CP) patients. This trial was registered at clinicaltrials.gov as NCT02594605. 16 patients (32 sites) with chronic periodontitis who had at least two areas of horizontal bone loss, were treated with OFD alone or L-PRF with OFD (OFD?+?L-PRF). GFL in gingival crevicular fluid (GCF) were analyzed at baseline, 1?week, 2?weeks and 4?weeks after operation. Probing depth (PD) and clinical attachment level (CAL) were measured at baseline and 6?months postoperatively. PD reduction and CAL gain were significantly higher in the OFD?+?L-PRF sites than in OFD sites. OFD?+?L-PRF group showed significantly increased bone morphogenetic protein-2 and insulin-like growth factor-1 at 2?weeks compared with baseline. L-PRF combined with OFD significantly increases GFL and thus, it enhances the periodontal healing on CP patients.     

The effect of a Beare‐Stevenson syndrome Fgfr2 Y394C mutation on early craniofacial bone volume and relative bone mineral density in mice

Quantifying the craniofacial skeletal phenotype during development highlights potential effects of known mutations on bone maturation and is an informative first step for the analysis of animal models. We introduce a novel technique to easily and efficiently quantify individual cranial bone volume and relative bone mineral density across the murine skull from high resolution computed tomography images. The approach can be combined with existing quantitative morphometric methods to provide details of bone growth and bone quality, which can be used to make inferences about regulatory effects local to individual bones and identify locations and developmental times for which additional analyses are warranted. Analysis of the Fgfr2^+/Y394C mouse model of Beare‐Stevenson cutis gyrata syndrome, an FGFR‐related craniosynostosis syndrome, is used to demonstrate the method. Mutants and unaffected littermates display similar bone volume and relative bone density at birth, followed by significant differences at postnatal day eight. The change in rates of bone volume growth occurs similarly for all bones of the skull, regardless of origin, location or association with craniosynostosis. These results suggest an association between low bone density, low bone volume, and Fgfr craniosynostosis mutations. Our novel technique provides an initial quantitative evaluation of local shifts in bone maturation across the skull of animal models.     

大鼠发育早期接触变应原对Th1/Th2亚群功能及哮喘发生的影响

目的探讨妊娠期母鼠及其子代接触尘螨点刺液（Derp）对发育后期个体Th1/Th2平衡及哮喘发生的影响。方法Wistar大鼠根据母体妊娠期及新生早期是否接触Derp随机分为对照组、母Derp-仔Derp-组（母鼠和其子代均未接触Derp）、母Derp＋仔Derp＋组（母鼠和其子代均接触Derp）和母Derp＋仔Derp-组（母鼠接触Derp,其子代未接触Derp）,分别皮下注射Derp或生理盐水,30d龄时除对照组外,其余3组以卵白蛋白（OVA）为变应原致敏并雾化吸入,诱发哮喘发生。取血浆检测OVA特异性IgE抗体、收集外周血单个核细胞（PBMC）用ELISA法检测培养上清中细胞因子IL-4和IFN-γ水平,行支气管肺泡灌洗记录支气管肺泡灌洗液（BALF）中嗜酸性粒细胞的计数,留取肺组织行病理学检查。结果母Derp＋仔Derp＋组在哮喘建模后PBMC培养上清中IFN-γ水平显著低于母Derp-仔Derp-组,IL-4水平显著升高,IL-4/IFN-γ比值升高,OVA特异性IgE、BALF中嗜酸性粒细胞计数显著高于母Derp-仔Derp-组;母Derp＋仔Derp-组与母Derp-仔Derp-组IL-4和IFN-γ水平差异均无统计学意义,OVA特异性IgE水平虽有增高,但差异不具统计学意义,BALF中嗜酸性粒细胞计数差异无统计学意义。母Derp＋仔Derp＋组Th2优势显著高于母Derp＋仔Derp-组。结论胎鼠对于Derp跨胎盘的致敏作用可通过母体妊娠期间的免疫来完成,这一过程会根本上导致Th2优势免疫的发生,增加了变态反应性疾病的危险性。