MicroRNA-143-3p ameliorates collagen-induced arthritis by polarizing naive CD4+ T cells into Treg cells.

BACKGROUND: Rheumatoid arthritis (RA) is a persistent and systemic autoimmunity disease. The abnormal differentiation of Treg cells is important in pathogenesis. Despite previous studies showed that microRNAs (miRNAs, miR) are pivotal modulators of Treg cells, the effect of miRNAs on Treg cell differentiation and function is not clear. Our study wants to reveal the relationship of miR-143-3p with the differentiative ability and biofunction of Treg cells during the development of RA. METHODS: The Expressing level of miR-143-3p and cell factor generation in peripheral blood (PB) of RA sufferers were identified by ELISA or RT-qPCR. The roles of miR-143-3p in Treg cell differentiation were studied via ShRNA/lentivirus transfection. Male DBA/1 J mice were separated into control, model, control mimics, and miR-143-3p mimics groups to analyze the anti-arthritis efficacy, the differentiative ability of Treg cells, and the expression level of miR-143-3p. RESULTS: Our team discovered that the Expressing level of miR-143-3p was related to RA disease activities in a negative manner, and remarkably related to antiinflammation cell factor IL-10. In vitro, the expression of miR-143-3p in the CD4+ T cells upregulated the percentage of CD4+ CD25+ Fxop3+ cells (Tregs) and forkhead box protein 3 (Foxp3) mRNA expression. Evidently, miR-143-3p mimic intervention considerably upregulated the content of Treg cells in vivo, validly avoided CIA progression, and remarkably suppressed the inflammatory events of joints in mice. CONCLUSION: Our findings indicated that miR-143-3p could ameliorate CIA through polarizing naive CD4+ T cells into Treg cells, which may be a novel strategy to treat autoimmune diseases such as RA.

Panax notoginseng saponins (PNS) attenuate Th17 cell differentiation in CIA mice via inhibition of nuclear PKM2-mediated STAT3 phosphorylation.

CONTEXT: Rheumatoid arthritis (RA) is an autoimmune disease with aberrant Th17 cell differentiation. Panax notoginseng (Burk.) F. H. Chen (Araliaceae) saponins (PNS) have an anti-inflammatory effect and can suppress Th17 cell differentiation. OBJECTIVE: To investigate mechanisms of PNS on Th17 cell differentiation in RA, and the role of pyruvate kinase M2 (PKM2). MATERIALS AND METHODS: Naive CD4+T cells were treated with IL-6, IL-23 and TGF-ß to induce Th17 cell differentiation. Apart from the Control group, other cells were treated with PNS (5, 10, 20 µg/mL). After the treatment, Th17 cell differentiation, PKM2 expression, and STAT3 phosphorylation were measured via flow cytometry, western blots, or immunofluorescence. PKM2-specific allosteric activator (Tepp-46, 50, 100, 150 µM) and inhibitor (SAICAR, 2, 4, 8 µM) were used to verify the mechanisms. A CIA mouse model was established and divided into control, model, and PNS (100 mg/kg) groups to assess an anti-arthritis effect, Th17 cell differentiation, and PKM2/STAT3 expression. RESULTS: PKM2 expression, dimerization, and nuclear accumulation were upregulated upon Th17 cell differentiation. PNS inhibited the Th17 cells, RORγt expression, IL-17A levels, PKM2 dimerization, and nuclear accumulation and Y705-STAT3 phosphorylation in Th17 cells. Using Tepp-46 (100 µM) and SAICAR (4 µM), we demonstrated that PNS (10 µg/mL) inhibited STAT3 phosphorylation and Th17 cell differentiation by suppressing nuclear PKM2 accumulation. In CIA mice, PNS attenuated CIA symptoms, reduced the number of splenic Th17 cells and nuclear PKM2/STAT3 signaling. DISCUSSION AND CONCLUSIONS: PNS inhibited Th17 cell differentiation through the inhibition of nuclear PKM2-mediated STAT3 phosphorylation. PNS may be useful for treating RA.

Triptolide inhibits Th17 differentiation via controlling PKM2-mediated glycolysis in rheumatoid arthritis.

CONTEXT: Rheumatoid arthritis (RA) is an autoimmune disease with the aberrant differentiation of T helper 17 (Th17) cells. Pyruvate kinase M2 (PKM2), a key enzyme of glycolysis, was associated with Th17 cell differentiation. AIM: To investigate the potential therapeutic effects of triptolide (TP) in collagen-induced arthritis (CIA) and Th17 cell differentiation, and elucidated the underlying mechanisms. METHODS: PKM2 expression and IL-17A production in peripheral blood of RA patients were detected by RT-qPCR or ELISA. Flow cytometry and ELISA were employed to assess the effect of Th17 cell differentiation by TP. PKM2 expression and other glycolysis-related factors were detected using RT-qPCR and Western Blot. PKM2 specific inhibitor Compound 3 K was used to verify the mechanisms. Male DBA/1J mice were divided into control, model, and TP (60 µg/kg) groups to assess the anti-arthritis effect, Th17 cell differentiation and PKM2 expression. RESULTS: PKM2 expression positively correlated with IL-17A production in RA patients. PKM2 expression was increased upon Th17 cell differentiation. Down-regulating PKM2 expression could strongly reduce Th17 cell differentiation. Molecular docking analysis predicted that TP targeted PKM2. TP treatment significantly reduced Th17 cell differentiation, PKM2 expression, pyruvate, and lactate production. In addition, compared with down-regulating PKM2 alone (Compound 3 K treatment), co-treatment with TP and Compound 3 K further significantly decreased PKM2-mediated glycolysis and Th17 cell differentiation. In CIA mice, TP repressed the PKM2-mediated glycolysis and attenuated joint inflammation. CONCLUSION: TP inhibited Th17 cell differentiation through the inhibition of PKM2-mediated glycolysis. We highlight a novel strategy for the use of TP in RA treatment.

[Research strategy of traditional Chinese medicine proteomics].

The application of proteomics in the research of traditional Chinese medicine (TCM) is very extensive, and there have been many successful cases. In this paper, the previous studies on the complex system of TCM by using proteomics technology were reviewed, and the authors proposed to set up a special subject on proteomics in TCM, which is called TCM proteomics. In this paper, the research strategies and the future research directions of TCM proteomics were reviewed and discussed, which may provide some ideas for the researchers of TCM proteomics.

Cajaninstilbene acid prevents corticosterone-induced apoptosis in PC12 cells by inhibiting the mitochondrial apoptotic pathway.

BACKGROUND/AIMS: Cajaninstilbene acid (3-hydroxy-4-prenyl-5-methoxystilben-2 -carboxylic acid, CSA), a natural stilbene isolated from the leaves of Cajanus cajan, has attracted considerable attention for its wide range of pharmacological activities. This study investigated whether CSA protects against corticosterone (CORT)-induced injury in PC12 cells and examined the potential mechanisms underlying this protective effect. METHODS: Cell viability and cytotoxicity were detected using a 3-(4,5-desethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) assay kit, respectively. PC12 cell apoptosis was measured using Hoechst 33342 staining and a DNA fragmentation assay kit, and intracellular Ca(2+) concentrations were assessed by fluorescent labelling. Next, the mitochondrial permeability transition pores (mPTPs) and mitochondrial membrane potentials (∆Ψm) were detected using a colorimetric mPTP detection kit and a 5,5',6,6'-tetrachloro-1,1',3,3'- tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) kit, respectively. Finally, cytochrome c, caspase-3 and inhibitor of caspase-activated deoxyribonuclease (ICAD) expression levels were monitored by western blot analysis. RESULTS: Treatment with 100 µmol/l CORT induced cytotoxicity in PC12 cells. However, CSA dose-dependently increased cell viability and decreased LDH release as well as CORT-induced apoptosis. Mechanistically, compared with the CORT-treated group, CSA strongly attenuated intracellular Ca(2+) overload and restored mitochondrial functions, including mPTPs and ∆Ψm. Furthermore, the down-regulation of cytochrome c and ICAD protein expression and the blockage of caspase-3 activity were observed upon CSA treatment. CONCLUSIONS: In summary, our data are the first to show that the in vitro antidepressant-like effect of CSA may be attributed to the cytoprotection of neurons and that such neuroprotective mechanisms are correlated with intracellular Ca(2+) homeostasis and mitochondrial apoptotic pathways.

[Neuroprotective effect of longistyline A against corticosterone-induced neurotoxicity in PC12 cells].

This study is to investigate the protective effect of longistyline A against corticosterone-induced neurotoxicity in PC12 cells. While PC12 cells were exposed to 100 micromol x L(-1) corticosterone for 48 h, cell survival rate was reduced and lactate dehydrogenase (LDH) release increased. In parallel, corticosterone caused significant elevations of DNA fragmentation, [Ca2+]i and caspase-3 activity. However, when the PC12 cells were incubated with longistyline A (4.0, 8.0 and 16.0 micromol x L(-1)) in the presence of 100 micromol x L(-1) corticosterone for 48 h, the effects were evidently alleviated, but dose-dependent manner was not obvious. In summary, longistyline A could generate a neuroprotective effect against corticosterone-induced neurotoxicity in PC12 cells possibly by decreasing [Ca2+]i and caspase-3 activity.

Th17 cell pathogenicity and plasticity in rheumatoid arthritis.

CD4+ Th cells play an important role in the development of rheumatoid arthritis (RA) by regulating adaptive immune response. As major subsets of CD4+ Th cells, Th17 cells can produce a large number of hallmark cytokines such as IL-17A and IL-17F, which participate in host defense and immune homeostasis. However, increasing researches have shown that Th17 cells are unstable and exhibit a certain degree of plasticity, which aggravates their pathogenicity. Furthermore, the plasticity and pathogenicity of Th17 cells are closely related with the disease activity in RA. In this paper, the characteristics including phenotype, differentiation, plasticity, and pathogenicity of Th17 cells in RA will be systematically summarized. This will contribute to clarify the immunologic mechanism of RA and further provide a novel strategy for the clinical treatment of autoimmune diseases.

Minocycline inhibits ICAD degradation and the NF-κB activation induced by 6-OHDA in PC12 cells.

6-Hydroxydopamine (6-OHDA) is a neurotoxin that is commonly employed to induce lesions of the dopaminergic pathways to generating experimental models of Parkinson's disease (PD) in rodents. Antioxidant and anti-inflammatory therapy approaches have been the focus of attention in the treatment of neurodegenerative. PD and Alzheimer's diseases, and oxidative stress have been implicated in these diseases. In this study, we investigated the neuroprotective effects of minocycline and the signalling pathway that is possibly involved in a PC12 cell model of PD. The results indicated that 6-OHDA cytotoxicity was accompanied by an increment in lactate dehydrogenase (LDH) release, an increase in caspase-3 protein activity, an increase in ROS generation, MDA content and decrease in the SOD, CAT activities and cell viability. Moreover, treatment with 6-OHDA alone for 24h resulted in ICAD degradation, increased nuclear translocation of NF-κB, and increased p53 expression. However, pretreatment with minocycline (5, 10, 20 µM) for 24h significantly reduced LDH release, reduced caspase-3 protein production, reduced ROS production, MDA content and attenuated the decrease in SOD, CAT activities and cell viability. Additionally, minocycline (20 µM) markedly decreased the levels of cleaved ICAD protein, down-regulated p53 activity and inhibited the nuclear translocation of NF-κB. The neuroprotective effects of minocycline were attributable to its potent antioxidant activities, which prevented the nuclear translocation of NF-κB and the subsequent promotion of cell death. Therefore, the present study supports the notion that minocycline may be a promising neuroprotective agent for the treatment of Parkinson's disease.