Apoptosis of osteoblasts triggered by high-dose glucocorticoids (GCs) has been identified as a major cause of osteoporosis. However, the molecular mechanisms underlying GC-induced osteoporosis remain elusive. This study was conducted to make clear the mechanism of GC-induced osteoblast apoptosis and to examine whether reduction of ER stress by 4-PBA inhibited osteoblast apoptosis. After treatment with dexamethasone (Dex) or hydrocortisone, cell viability was assessed using an MTT assay. Flow cytometry was performed to assess the apoptosis of MC3T3-E1 cells. The expression levels of ER stress-related proteins (CHOP, GRP78, eIF2α, and phospho-eIF2α) and apoptosis-related proteins (cleaved Caspase-3, Bcl-2, and Bax) in MC3T3-E1 cells were measured by Western blot analysis. We found that both Dex and hydrocortisone reduced cell proliferation and promoted apoptosis in MC3T3-E1 cells. In addition, the protein expression levels of cleaved Caspase-3 and Bax increased and the protein expression level of Bcl-2 decreased in MC3T3-E1 cells exposed to Dex. In addition, the Dex exposure also resulted in a release of cytochrome c (Cyt C) from mitochondria. The cellular ATP content was decreased following prolonged treatment with Dex. 4-PBA attenuated ER stress and mitochondrial dysfunction induced by Dex in MC3T3-E1 cells. Dex-mediated apoptosis of MC3T3-E1 cells is aggravated by ER stress. Moreover, Dex-induced apoptosis in MC3T3-E1 cells was inhibited by 4-PBA, suggesting that ER stress involved in Dex-induced apoptosis. In conclusion, inhibition of ER stress by 4-PBA could reduce GC-induced apoptosis in MC3T3-E1 cells.

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Objective:This meta-analysis aimed to illustrate the efficacy and safety of preganalin for pain management in patients with postherpetic neuralgia (PHN).Methods:In July 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews, and Google database. Data on patients with PHN that compared pregabalin versus placebo were retrieved. The endpoints were the visual analog scale (VAS) at 8 weeks, the percentage of 30% and 50% pain responders; sleep interference score and improvement in patient global impression of change (PGIC). After testing for publication bias and heterogeneity between studies, data were aggregated for random-effects models when necessary.Results:Seven clinical studies with 2192 patients (pregabalin group = 1381, control group = 811) were finally included in the meta-analysis. Pregabalin was associated with reduced pain scores at 8 weeks, corresponding to a reduction of 11.23 points (95% CI, −14.33, −8.13, P = .000) on a 100-point VAS. Pregabalin was also associated with a more percentage of 30% and 50% pain responders than controls (P < .05). Meanwhile, pregabalin can decrease sleep interference score and improvement in PGIC than control groups (P < .05).Conclusions:Pregabalin was efficacious in the reduction of postoperative pain and improvement the sleep quality in patients with PHN.

Both TDD and nucleoplasty can reduce pain in patients with lumbar disc herniation and improve quality of life. Group N had shorter hospitalization and operation time than group T.