RESUMO
As an inhibitor of the Notch signaling pathway, N-[N-(3,5-difluorohenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester (DAPT) may protect brain tissue from serious ischemic injury. This study aimed to explore neuroprotection by DAPT after cerebral ischemia/reperfusion (I/R) injury. DAPT was intraperitoneally injected 3 hours before the establishment of a focal cerebral I/R model in the right middle cerebral artery of obstructed mice. Longa scores were used to assess neurological changes of mice. Nissl staining and TdT-mediated dUTP-biotin nick-end labeling staining were used to examine neuronal damage and cell apoptosis in the right prefrontal cortex, while immunofluorescence staining was used to detect glial fibrillary acidic protein- and Notch1-positive cells. Protein expression levels of Hes1 and Hes5 were detected by western blot assay in the right prefrontal cortex. Our results demonstrated that DAPT significantly improved neurobehavioral scores and relieved neuronal morphological damage. DAPT decreased the number of glial fibrillary acidic protein- and Notch1-positive cells in the right prefrontal cortex, while also reducing the number of apoptotic cells and decreasing interleukin-6 and tumor necrosis factor-α contents, and simultaneously downregulating Hes1 and Hes5 protein expression. These findings verify that DAPT alleviates pathological lesions and strengthens the anti-inflammatory response after cerebral I/R injury. Thus, DAPT might be developed as an effective drug for the prevention of cerebral I/R injury.
RESUMO
OBJECTIVE: To research the diagnostic performance of clinical potential bone turnover indexes in rheumatoid arthritis (RA) complicated with osteoporosis (OP). METHODS: This study involved 87 RA patients, 48 with OP, and 39 without OP, and 204 non-RA control patients, including those with systemic lupus erythematosus, ankylosing spondylitis, primary Sjogren's syndrome, systemic sclerosis, and healthy patients. The levels of 25-hydroxyvitamin D [25(OH)D], ß-crosslaps (ß-CROSSL), parathyroid hormone (PTH) were measured by electrochemiluminescence (ECLIA), and the level of bone alkaline phosphatase (BALP) was measured by lectin affinity method. RESULTS: The serum concentration of 25(OH)D in the RA with OP group was significantly lower than the control group (P<0.01), while the levels of ß-CROSSL, BALP in the RA with OP group considerably exceeded those found in the control group (P<0.01). The levels of ß-CROSSL and PTH were significantly higher in RA patients with OP than without OP (P<0.01), while the level of 25(OH)D was statistically lower than without OP (P<0.01). An unconditional logistical regression analysis proved an association with low 25(OH)D and elevated ß-CROSSL in RA with OP, with 25(OH)D demonstrating greatest diagnostic potential according to the ROC curve. CONCLUSION: The significantly reduced levels of 25(OH)D and excessive ß-CROSSL may indicate a high risk of the secondary osteoporosis in RA patients.
