METTL14 promotes fibroblast-like synoviocytes activation via the LASP1/SRC/AKT axis in rheumatoid arthritis.

The objective of this study is to explore the specific roles of a crucial N6-methyladenosine (m6A) methyltransferase, methyltransferase-like 14 (METTL14), in fibroblast-like synoviocytes (FLSs) activation of rheumatoid arthritis (RA). RA rat model was induced by administering intraperitoneally collagen antibody alcohol. Primary fibroblast-like synoviocytes (FLSs) were isolated from joint synovium tissues in rats. shRNA transfection tools were used to downregulate METTL14 expression in vivo and vitro. The injury of joint synovium was shown by hematoxylin and eosin (HE) staining. The cell apoptosis of FLSs was determined by flow cytometry. The levels of IL-6, IL-18, and C-X-C motif chemokine ligand (CXCL)10 in serum and culture supernatants were measured by ELISA kits. The expressions of LIM and SH3 domain protein 1 (LASP1), p-SRC/SRC, and p-AKT/AKT in FLSs and joint synovium tissues were determined by Western blots. The expression of METTL14 was greatly induced in the synovium tissues of RA rats compared with normal control rats. Compared with sh-NC-treated FLSs, METTL14 knockdown significantly increased cell apoptosis, inhibited cell migration and invasion, and suppressed the production of IL-6, IL-18, and CXCL10 induced by TNF-α. METTL14 silencing suppresses the expression of LASP1 and the activation of Src/AKT axis induced by TNF-α in FLSs. METTL14 improves the mRNA stability of LASP1 through m6A modification. In contrast, these were reversed by LASP1 overexpression. Moreover, METTL14 silencing clearly alleviates FLSs activation and inflammation in a RA rat model. These results suggested that METTL14 promotes FLSs activation and related inflammatory response via the LASP1/SRC/AKT signaling pathway and identified METTL14 as a potential target for treating RA.

N-Allylation versus C-allylation of intermediates from aza-Michael adducts of arylideneisoxazol-5-ones.

Reactions of arylidene-isoxazol-5-ones with intermediates from palladium-catalysed decarboxylation of allyl carbamates proceeded through aza-Michael addition and N-allylation to give the corresponding bis-adducts, ß-amido-N-allylated products, in good yields. In similar reactions with 4-vinyl-1,4-dihydro-2H-3,1-benzoxazin-2-one, a cyclic allyl carbamate, C-allylation took place to yield a series of spiro[isoxazole-4,3'-quinolin]-5-ones in high yields. Regio-selective N- versus C-allylation is illustrated to occur in an inter- versus intra-molecular fashion. The structure and stereochemistry of these products are determined by NMR spectroscopy and further confirmed by X-ray crystallography. This work offers an excellent method for the preparation of various substituted isoxazol-5-ones.

Is tea consumption associated with the serum uric acid level, hyperuricemia or the risk of gout? A systematic review and meta-analysis.

BACKGROUND: The aim of this study was to examine the associations of tea consumption with the serum uric acid (SUA) level, hyperuricemia (HU) and the risk of gout. METHODS: A comprehensive literature search up to June 2016, using PUBMED and EMBASE databases, was conducted to identify the relevant observational studies that examined the associations of tea consumption with the SUA level, HU and the risk of gout. RESULTS: A total of fifteen observational studies were included in this study, and nine studies were extracted for meta-analysis. For the SUA level, seven studies were included. According to the combined weighted mean difference (WMD), there was no significant difference between the highest and the lowest tea intake category in terms of the SUA level (WMD = 7.41 µmol/L, 95%CI: -2.34 to 17.15; P = 0.136). In subgroup analysis including three studies, green tea consumption was positively associated with the SUA level (WMD = 17.20 µmol/L, 95%CI: 7.00 to 27.40; P = 0.01). For the prevalence of HU, five studies were included. The overall multi-variable adjusted odds ratio (OR) for the highest versus the lowest category of tea consumption was 0.98 (95%CI: 0.77 to 1.24; P = 0.839). For the risk of gout, two prospective cohort studies showed that there was no relationship between tea consumption and the risk of gout in males and females, respectively. CONCLUSION: The current evidences suggest that tea consumption does not seem to be associated with the SUA level, HU and the risk of gout. However, due to the limited number of studies, green tea consumption might be positively associated with the SUA level. More well-designed prospective cohort studies are needed to elaborate these issues further.

[Amino acids 395-416 in DNA binding domain of STAT4 is involved in IL-12-induced nuclear import of STAT4].

The purpose of the present study is to explore the mechanism of IL-12-induced nuclear import of signal transducer and activator of transcription 4 (STAT4). Assayed by analyses of homology alignment of STATs, amino acids 395-416 in DNA binding domain was found to be a potential dimer-specific nuclear localization signal (dsNLS) of STAT4. Therefore, several plasmids were constructed. Wild-type STAT4 was inserted into the SalI and BamHI sites of pEGFP-C1 for the construction of plasmid pEGFP-STAT4. The DNA fragment of STAT4 with the deletion of amino acids 395-416 was amplified by RCR and introduced into the SalI and BamHI sites of pEGFP-C1 which was named pEGFP-STAT4-Del. Classic NLS DNA sequence of SV40 T antigen was inserted into the XhoI and HindIII sites of pEGFP-C1. This plasmid was named as pEGFP-NLS and used as a positive control. Plasmid pEGFP-NLS-STAT4-Del was constructed by inserting STAT4-Del into SalI and BamHI sites of pEGFP-NLS. These plasmids were transiently transfected into Caski cells, respectively. The results showed that, after these transfected cells were stimulated by IL-12, wild type STAT4 existed in the cytoplasm at 0 min, and was predominantly localized to the nucleus at 45 min, and distributed in both cytoplasm and nucleus at 60 min, suggesting that STAT4 translocates from cytoplasm into nucleus and finally re-entries into the cytoplasm during the stimulation of IL-12. However, deletion mutant of STAT4 was arrested in cytoplasm during the IL-12 stimulation. Leptomycin B, which specifically blocks protein export from nucleus into cytoplasm, was used to further demonstrate whether STAT4-Del is transferred into nucleus even with stimulation of IL-12. After the transfected cells were pre-treated by leptomycin B, the wild type STAT4 was mainly localized in nucleus after the IL-12 stimulation, suggesting that STAT4 was translocated from cytoplasm into nucleus by the stimulation of IL-12. On the other hand, the deletion mutant of STAT4 distributed in cytoplasm throughout, implying that the mutant STAT4 lacking of amino acids 395-416 cannot move into nucleus. Furthermore, the insertion of classic NLS into EGFP-STAT4-Del restored nuclear import of STAT4-Del. These results suggest the amino acids 395-416 is a dsNLS mediating IL-12-stimulated nuclear import of activated STAT4.

Decompressive craniectomy can improve the recovery of neurological function, daily living ability and life quality of patients with intracerebral hemorrhage after surgery.

OBJECTIVE: To determine the effect of decompressive craniectomy (DC) on the recovery of neurological function, daily living ability and life quality of patients with intracerebral hemorrhage (ICH) after surgery. METHODS: Totally 290 patients with ICH admitted to our hospital from January 2018 to June 2020 were retrospectively enrolled and assigned to two groups according to different surgical methods. Among them, 138 patients who received craniotomy evacuation of hematoma (CEH) only were assigned to a control group (Con group), while the other 152 who received CEH combined with DC to a research group (Res group). The two groups were compared in the total effective rate, hematoma clearance rate, and complication rate. Additionally, the ICP and MMP-9 levels after surgery, National Institutes of Health Stroke Scale (NIHSS), activities of daily living (ADL), Fugl-Meyer Assessment of motor function (FMA), Glasgow outcome scale (GOS), Glasgow coma scale (GCS), and MOS 36-Item Short-Form Health Survey (SF-36) scores before and after surgery were also compared between the two groups. RESULTS: After treatment, the Res group showed a notably higher total effective rate, hematoma clearance rate, and a notably lower complication rate than the Con group. On postoperative day 3 and 7, the Res group showed notably lower ICP than the Con group, and on postoperative day 7, the Res group showed a notably lower MMP-9 level as compared with the Con group. Additionally, 6 months after the surgery, the Res group got notably lower NIHSS scores and higher ADL, GOS, and SF-36 scores as compared with the Con group, and at 1 month after surgery, the Res group got notably higher FMA scores as compared to the Con group. Moreover, on postoperative day 7, the Res group got notably higher GCS scores than the Con group. CONCLUSION: DC can improve the recovery of neurological function, daily living ability and life quality of patients with ICH after surgery.

Overactivated autophagy contributes to steroid-induced avascular necrosis of the femoral head.

Steroid-induced avascular necrosis of the femoral head (SANFH) is a mainly bilateral complication of steroid therapy that involves extensive necrosis, and frequently occurs in young and middle-aged individuals, with a high disability rate. Autophagy is an intracellular lysosomal degradation process occurring in numerous diseases. However, the effect of dexamethasone (DXM)-induced autophagy on osteoblasts is unclear. The aim of the present study was to investigate the effects of autophagy on SANFH. In the present study, femoral head of SANFH patients was collected, and the autophagy in the samples was evaluated. In addition, cell proliferation, membrane integrity and differentiation of osteoblasts were also detected to confirm the effect of DXM on a mouse osteoblasts cell MC3T3-E1 in vitro. Beclin 1 and microtubule-associated protein 1 light chain 3 were used as the markers of autophagy, while the autophagy inhibitor 3-methyladenine (3-MA) was used to investigate the role of autophagy in DXM-challenged osteoblasts. Immunohistochemistry results demonstrated that Beclin1 was markedly increased in the femoral head of SANFH patients. Furthermore, the treatment of osteoblasts with DXM decreased cell viability, increased lactate dehydrogenase activity in the cell culture supernatant, and reduced the alkaline phosphatase activity and bone morphogenetic protein-2 expression in osteoblasts in vitro. By contrast, 3-MA treatment attenuated the cell injury induced by DXM. The present study indicates that overactivated autophagy may be an important factor contributing to SANFH, and autophagy may be a potential target for the prevention of SANFH.

Wogonoside induces apoptosis in Bel-7402, a hepatocellular carcinoma cell line, by regulating Bax/Bcl-2.

The anticancer effect of Scutellaria baicalensis extract has recently become a topic of interest. In this study, the anticancer effects and underlying mechanisms of wogonoside, the main constituent of Scutellaria baicalensis, were investigated in a human hepatocellular carcinoma (HCC) cell line in vitro. The effects of wogonoside on the proliferation, cell cycle progression and apoptosis of hepatocellular carcinoma cells were examined. Western blotting was employed to analyze the proteins associated with the biological effects of wogonoside. Wogonoside exerted anti-proliferation properties in vitro. HCC cell growth was attenuated by wogonoside (8 µM) treatment. Cell cycle progression analysis and DNA ladder assay revealed that apoptosis was enhanced in wogonoside-treated cells and that cell cycle arrest occurred in the G2/M phase. It was also demonstrated that increased apoptosis was accompanied by increased levels of Bax protein and decreased levels of Bcl-2 protein. The results of this study suggest that wogonoside may represent a potential therapeutic agent against HCC.