Effects of daphresin on synovial fibroblasts in rheumatoid arthritis based on PERK/ATF4/CHOP signaling pathway / 中国药理学通报

Aim To investigate the effects of DAP on human rheumatoid arthritis synovial fibroblasts(RA-FLS)and its relationship with endoplasmic reticulum stress(ERS)PERK/ATF4/CHOP signaling pathway.Methods RA-FLS cells were cultured and identified by immunofluorescence assay for Vimentin and CD68.CCK-8 detected(0,5,10,20,30,40,50,60,70)mg·L-1 DAP on the proliferation activity of RA-FLS cells.According to the proliferation activity,the experiment was divided into blank group(Blank),low dose group(L-DAP),medium dose group(M-DAP),high dose group(H-DAP)and high dose+specific inhibitor 4-PBA group(H-DAP+4-PBA).The levels of TNF-α and IL-6 were detected by ELISA.Cell apoptosis was detected by flow cytometry.The invasion and migration of cells were detected by Transwell and scratches assays,and the expressions of endoplasmic reticulum stress-related proteins GRP78,PERK,P-PERK,ATF4,CHOP,Caspase-12,C-Caspase-12 and Bcl-2 were assessed by Western blot.Results CCK-8 results showed that compared with 0 mg·L-1 DAP group,the proliferation activity of each group in 20-70 mg·L-1 DAP group was significantly different(P<0.05),and the proliferation rate corresponding to 0,20,40 and 60 mg·L-1 DAP group was significantly different(P<0.05).This concentration was used as the basis for blank,low-dose,medium-dose,high-dose groups and high-dose+4-PBA experimental grouping.DAP could inhibit the release of inflammatory cytokines IL-6 and TNF-α from RA-FLS cells in concentration,reduce the invasion ability of cells,promote apoptosis,upregulate the expression of PERK,P-PERK,ATF4,GRP78,CHOP,Caspase-12, C-caspase-12 proteins and decrease the expression level of anti-apoptotic protein Bcl-2.Another set of experiments demonstrated that high dose DAP+4-PBA could up-regulate the expression of IL-6 and TNF-α,as well as the invasion of cells,and inhibit the expression of apoptosis and ERs-related proteins.Conclusions Daphresin regulates the secretion of inflammatory factors by activating the PERK/ATF4/CHOP signaling pathway,inhibits the proliferation and invasion of RA-FLS cells,and induces apoptosis,which is expected to be a potential therapeutic pathway for RA.

Identification of microRNAs targeting vitamin D receptor and their effect on parathyroid hormone secretion in secondary hyperparathyroidism / 南方医科大学学报

OBJECTIVE@#To identify the miRNAs targeting vitamin D receptor (VDR) gene and their effect on parathyroid hormone (PTH) secretion in secondary hyperparathyroidism.@*METHODS@#Primary parathyroid cells with secondary hyperparathyroidism were isolated by collagenase digestion and cultured. The miRNAs targeting VDR were screened by bioinformatics methods and full transcriptome sequencing, and dual-luciferase reporter assay was used to verify the targeting relationship between VDR and the screened miRNA. The effects of overexpression or inhibition of the candidate miRNA on VDR mRNA and protein expressions and PTH secretion were evaluated using qRT-PCR and Western blotting. The expression levels of the candidate miRNAs and VDR mRNA in clinical specimens of parathyroid tissues were verified by qRT-PCR, and the expression of VDR protein was detected by immunohistochemistry.@*RESULTS@#We successfully isolated primary parathyroid cells. Dual-luciferase reporter assay verified the targeting relationship of hsa-miR-149-5p, hsa-miR-221-5p, hsa-miR-222-3p, hsa-miR-29a-5p, hsa-miR-301a-5p, hsa-miR-873-5p, hsa-miR-93-3p with VDR, and among them, the overexpression of hsa-miR-149-5p and hsa-miR-301a-5p significantly increased PTH secretion in the parathyroid cells. In patients with secondary hyperparathyroidism, hsa-miR-149-5p was highly expressed in the parathyroid tissues (P=0.046), where the expressions of VDR mRNA (P=0.0267) and protein were both decreased.@*CONCLUSION@#The two miRNAs, hsa-miR-149-5p and hsa-miR-301a-5p, may promote the secretion of PTH in patients with secondary hyperparathyroidism by down-regulating the expression of VDR gene.

Cultivation and characterization of primary human parathyroid cells from patients with severe secondary hyperparathyroidism / 南方医科大学学报

OBJECTIVE@#To establish an cell model of hyperparathyroidism by isolation, in vitro culture, and identification of parathyroid cells from patients with secondary hyperparathyroidism (SHPT).@*METHODS@#The parathyroid gland tissues obtained from 10 patients with SHPT were dissociated by collagenase digestion for primary culture of the parathyroid cells. Morphological changes and growth characteristics of the cells were assessed by microscopic imaging and cell counting. The mRNA and protein expression levels of parathyroid hormone (PTH), calcium-sensing receptor (CaSR), and glial cells missing 2 (GCM2) in the primary and passaged cells were determined by immunofluorescence, qRT-PCR, and Western blotting.@*RESULTS@#Primary cultures of parathyroid cells were successfully obtained. The cells exhibited a high expression of PTH shown by immunofluorescence assay and had a population doubling time of approximately 71.61 h. PTH secretion in the second-passage (P2) cells was significantly lower than that in the primary (P0) and first-passage (P1) cells (P < 0.001). Despite a significant downregulation of CaSR mRNA (P=0.017) and protein (P=0.006) in P1 cells as compared with P0 cells, no significant differences were found in mRNA and protein expressions of PTH or GCM2 between the two cell generations.@*CONCLUSION@#Primary cultures of parathyroid cells isolated from SHPT patients by collagenase digestion show similar biological properties to the cells in vivo.