MiR-146a mediates TLR-4 signaling pathway to affect myocardial fibrosis in rat constrictive pericarditis model

BackgroundMyocardial fibrosis (MF) is thought to be associated with constrictive pericarditis (CP). miR-146a has been reported to be related to the survival of myocardial fibroblasts and related signal transduction pathways. The aim of this study was to investigate the expression of miR-146a in CP with MF and the activation of the Toll-like receptor 4 (TLR-4) signaling pathway, to understand the molecular mechanism of MF involvement in CP.MethodsThirty rats with different disease duration were randomly divided into three groups: an 8-week model group (CP-8W group), a 16-week model group (CP-16W group) model, and a normal control group (N group). After the CP model was established in the rats, the myocardial tissues were collected. The expression of miR-146a, the key factors of TLR-4 signaling pathway, including IL-1 receptor-associated kinase 1 (IRAK1), tumor necrosis factor receptor-associated factor 6 (TRAF6), nuclear factor-κB (NF-κB) and p-NF-κB, and the MF indicator α-SMA in myocardial tissue were detected. After treatment with lipopolysaccharide (LPS), primary cultured rat cardiac fibroblasts (CFs) were transfected with miR-146a. RT-PCR and western blot were used to detect the expression of downstream effectors to further verify the function of miRNA-146a in regulating MF via the TLR-4 signaling pathway.ResultsmiR-146a was increased in the CP-8W group but not in the CP-16W group. IRAK1 and TRAF6 in the CP-16W group were found to be higher than in the N group and CP-8W group. α-SMA in the model groups was higher than in the N group. Compared with the CP-8W group, α-SMA in the CP-16W model group was further increased. In the experiments using CFs, the expression of IRAK1, TRAF6, p-NF-κB and α-SMA increased in the LPS-treated group compared with the N group. After transfection of CFs with the miR-146a mimics, the expression of IRAK1, TRAF6, p-NF-κB and α-SMA decreased compared with the LPS-treated group. Following transfection of CFs with miR-146a inhibitors, the expression of IRAK1, TRAF6, p-NF-κB and α-SMA increased compared with the LPS-treated group.ConclusionsThe expression of miR-146a demonstrated a dynamic change in the CP model; it was increased at the early time point (CP-8W) and then decreased at the 16W time point. miR-146a suppressed MF by inhibiting the target genes TRAF6 and IRAK1 via the TLR-4 signaling pathway.     

A case of erythrodermic psoriasis successfully treated with ixekizumab

Erythrodermic psoriasis (EP) is the most severe form of psoriasis, resulting in significant morbidity and mortality. International guidelines on EP treatment are lacking, with most of the biologic drugs being used basing on case reports or small case series. Ixekizumab, a fully human anti‐interleukin (IL)‐17A monoclonal antibody, is approved for moderate to severe plaque psoriasis while its use in EP is off label. However, two studies conducted on eight Japanese EP patients have showed ixekizumab as an efficacious and well tolerated therapy up to 24 and 52 weeks, respectively. To date, no case reports on Caucasian patients have been described. We report the case of a 66‐year‐old Caucasian female with EP successfully treated with ixekizumab, reaching PASI 100 after only 6 weeks of therapy and still maintaining this response at week 24. Our case report suggests ixekizumab as a highly efficacious treatment in EP, presenting also a very rapid action which leads to complete resolution of the disease after 6 weeks. Further studies are warrant to confirm our data, with controlled trials specifically dedicated to EP being strictly needed in order to verify the role and efficacy of the new biologics in EP.     

Remote control over guidance and release properties of composite polyelectrolyte based capsules

Polyelectrolyte multilayer capsules represent a unique tool to fabricate micron- and submicron-sized delivery systems with the properties of external guidance by means of remote physical influence. Embedding of nanoparticles into polyelectrolyte multilayer constructs opens up the opportunities to navigate the capsules with magnetic field and in-situ trigger the release of encapsulated material in response to the physical stimuli, such as light and ultrasound. So far, optically- and magnetically-induced addressing of the polyelectrolyte multilayer capsules internalized by the living cells in-vitro has been demonstrated. In this review, we discuss the state of the art, future perspectives and anticipated obstacles of in-vivo and in-vitro applications of the polyelectrolyte capsules performing remotely controlled release delivery of bioactives.     

Layer-by-layer capsules for magnetic resonance imaging and drug delivery

Layer-by-layer (LbL) self-assembled polyelectrolyte capsules have demonstrated their unique advantages and capability in drug delivery applications. These ordered micro/nano-structures are also promising candidates as imaging contrast agents for diagnostic and theranostic applications. Magnetic resonance imaging (MRI), one of the most powerful clinical imaging modalities, is moving forward to the molecular imaging field and requires the availability of advanced imaging probes. In this review, we are focusing on the design of MRI visible LbL capsules, which incorporate either paramagnetic metal-ligand complexes or superparamagnetic iron oxide (SPIO) nanoparticles. The design criteria cover the topics of probe sensitivity, biosafety, long-circulation property, targeting ligand decoration, and drug loading strategies. Examples of MRI visible LbL capsules with paramagnetic or superparamagnetic moieties were given and discussed. This carrier platform can also be chosen for other imaging modalities.     

An alternative renewable source of squalene for use in emulsion adjuvants

Emulsions have been used to boost immunogenicity of antigens since the discovery of complete Freunds adjuvant. Optimization to reduce reactogenicity of emulsion adjuvants lead to the development of oil in water emulsions based on squalene. MF59 is an oil-in-water emulsion that is a component of an approved influenza product in Europe. Currently MF59 is manufactured from squalene derived from an animal source. Recently a high purity plant-derived squalene source has become available at an appropriate purity for a vaccine adjuvant. The purpose of this study was to evaluate and compare animal-derived squalene and plant-derived squalene for equivalency. Nanoemulsions were prepared and analyzed for size and viscosity prepared from each source. The two emulsions were administered in two separate animal studies, one focusing on Neisseria meningitidis B, and one focusing on influenza. Readouts were ELISA titers for each antigen and serum bactericidal activity for N. meningitidis B, and hemagglutinin inhibition for influenza to see the functionality of the antibodies produced. Results indicate that there are no differences between the antibodies elicited after immunization from an emulsion made with oil derived from either an animal or plant-source.     

Phytochemical study guided by the myorelaxant activity of the crude extract,fractions and constituent from stem bark of Hymenaea courbaril L.

Ethnopharmacological relevance

Hymenaea courbaril L. (Caesalpinoideae) is used in Brazilian folk medicine to treat anemia, kidney problems, sore throat and other dysfunctions of the respiratory system, such as bronchitis and asthma, although such properties are yet to be scientifically validated.

Aim of the study

In order to give a scientific basis to support the traditional use of Hymenaea courbaril, this study was designed to evaluate antioxidant, myorelaxant and anti-inflammatory properties of the ethanol extract from stem bark and its fractions. The myorelaxant effect of astilbin, a flavonoid isolated from the bioactive ethyl acetate fraction (EAF), has also been evaluated.

Material and methods

In the present study ethanol extract from stem bark (EEHC) and fractions were analyzed using bioassay-guided fractionation. The following activities were investigated: antioxidant by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, myorelaxant on rat tracheal smooth muscle, and anti-inflammatory using ovalbumin-induced leukocytosis and airway hyperresponsiveness in rats.

Results

The results of the present investigation show that the whole extract of Hymenaea courbaril and some of its fractions strongly scavenged DPPH radical. The extract showed myorelaxant activity on rat trachea, being EAF its highest efficient fraction. Bio-guided study allowed the isolation of astilbin, a well-known flavonoid. The activity induced by this compound indicates that it may be partly responsible for the myorelaxant effect of EAF. EAF reduced contractions that depended on divalent cation inflow through voltage-operated Ca²⁺ channels (VOCCs) or receptor-operated Ca²⁺ channels (ROCCs), but it was more potent to inhibit VOCC- than ROCC-dependent contraction induced by Ca²⁺ addition in ACh-enriched Ca²⁺-free medium. Oral pretreatment of antigen-challenged animals with EAF prevented airway hyperresponsiveness on KCl-induced contraction and reduced the number of total white cells, particularly eosinophils and neutrophils in bronchoalveolar lavage.

Conclusions

This study provided scientific basis that Hymenaea courbaril presents potential antioxidant, myorelaxant and anti-inflammatory actions, which support its use in folk medicine to treat inflammatory airway diseases.     

红细胞生成素诱导小鼠骨髓纤维化模型的实验研究

本研究旨在利用大剂量人重组红细胞生长素(rhEPO)诱导骨髓纤维化(MF)小鼠模型.60只昆明小鼠分为正常对照和EPO诱导组,分别用生理盐水和rhEPO进行腹腔注射,在实验第6、30、60、90、120和150天每组分别处死5只鼠.用细胞分析仪测定外周血白细胞数、血红蛋白(Hb)水平、红细胞平均体积(MCV)、红细胞分布宽度(RDW)和血小板量;用流式细胞术检测骨髓CD34阳性细胞率,称重肝、脾,计算肝、脾系数,利用HE和网状纤维染色分析肝、脾、股骨病理变化;应用高清CT测定股骨皮质厚度、髓腔直径和腰椎密度.结果表明,与正常对照组相比,EPO组各阶段白细胞轻度增高,但无统计学差异(p>0.05);Hb和RDW在第6和30天增高显著(p<0.05);MCV在第6天增高显著(p<0.05);各阶段血小板数降低,在第120和150天差异显著(p<0.05).EPO组第60天肝肿大明显,肝系数差异显著(p<0.05);各阶段脾肿大,脾系数差异显著(p<0.05).EPO组各阶段骨髓CD43阳性细胞率显著增高(p<0.05),第150天CT显示股骨皮质增厚,髓腔变窄,密度不均,腰椎密度增高.病理检查显示,EPO组小鼠肝脂肪化和空泡化,脾脏巨核细胞增多,股骨硬化和骨髓纤维组织增多.结论:大剂量rhEPO可诱导小鼠出现MF特有临床和病理特点.本研究对建立新的MF模型和病理研究有重要意义.     

Human platelet FcγRIIA and phagocytes in immune-complex clearance

In addition to their primary role in hemostasis and wound healing, platelets play important roles in a multitude of physiological functions including immune and inflammatory responses. We present data that platelets, by virtue of their expression of the human specific FcγR, FcγRIIA, bind IgG complexes in vivo and that circulating phagocytes from healthy individuals internalize platelets in vivo. Human platelets, as a consequence of their expression of FcγRIIA, may thus, contribute to the clearance of IgG-containing complexes from the circulation.