Purpose To evaluate the prostag landins(PG) levels and to identify the effect of dexamethasone(DXM) on PG in response to photochemical insult in rat retina. Methods The experiments were performed on 36 SD rats which were separated into two groups,control and treated groups,and the latter received daily intraperitoneal injections of DXM (1 mg/kg) for 5 consecutive days,starting 3 days before light exposure.The animals were continually exposed to green fluorescent light(510-560 nm)with an illuminance level of (1900plusmn;106.9)lx for 24 hrs.The retinal concentration of PGE 2 and 6-keto-PGF1alpha; were tested at 6hrs,1,3,7 and 14 days after light exposure. Results The PGE2 and 6-keto-PGF1alpha; levels of the control groups (37.50plusmn;2.75,48.06plusmn;4.0 4,81.90plusmn;4.89) pg/mg and (4.68plusmn;0.69,7.50plusmn;0.57,10.40plusmn;0.71) pg/mg had significantly higher values than those of the treated rats(20.60plusmn;4.28,37.36plusmn; 3.34,54.85plusmn;4.57) pg/mg and (2.50plusmn;0.59,4．68plusmn;0.81,6.87plusmn;1.10)pg/mg (Plt;0.01) after 6 hrs,1 and 3 days light exposure respectively. Conclusion By inhibition of PG synthesis,the DXM may play an ameliorative effect on retinal photochemical injury of rats. (Chin J Ocul Fundus Dis,1999,15:94-96)
ObjectiveTo systematically review the efficacy and safety of dexamethasone in the treatment of viral myocarditis.MethodsThe Cochrane Library, PubMed, EMbase, Biosis Preview, Web of Science, CBM, WanFang Data, VIP, and CNKI databases were electronically searched to collect randomized controlled trials (RCTs) on dexamethasone for patients with viral myocarditis from inception to April 30th, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed using RevMan 5.4 software.ResultsA total of 7 RCTs involving 749 patients were included. The results of meta-analysis showed that the dexamethasone treatment group exhibited an increased efficacy rate (RR=1.26, 95%CI 1.18 to 1.34, P<0.000 01), decreased levels of C-reactive protein (CRP) (MD=−11.49, 95%CI −19.25 to −3.72, P=0.004), cardiac troponin I (cTnI) (MD=−26.14, 95%CI −40.82 to −11.47, P=0.0005), and creatine kinase MB (CK-MB) (MD=−20.06, 95%CI −28.35 to −11.77, P<0.000 01), and a decreased adverse event rate (RR=0.40, 95%CI 0.24 to 0.65, P=0.000 3).ConclusionsCurrent evidence shows that dexamethasone can significantly improve the efficacy rate, reduce the levels of CRP, cTnI, and CK-MB, and reduce the incidence of adverse events in patients with viral myocarditis. Due to the limited quantity and quality of included studies, more high-quality studies are required to verify above conclusions.
Objective To explore the value and clinical safety of low-dose dexamethasone used after operation of anastomotic colorectal resection with fast-track surgery in patients with colorectal cancer. Methods Between January 2008 and December 2009, 470 patients undergoing anastomotic colorectal resection were analyzed retrospectively, who were divided into dexamethasone group and control group according to the use of low-dose dexamethasone treatment or not after operation. Postoperative adverse effect, complications, and early rehabilitations were studied. Results There was no statistical significance in postoperative incidence of adverse effect or complications between two groups (Pgt;0.05). In early rehabilitation, first ambulation of patients in the dexamethasone group was significantly earlier than that in the control group (Plt;0.05), while there was no statistical significance in first time of passing flatus, stool, and oral intake, the retain time of nasogastric tubes, urinary catheter, and drains, and postoperative hospital stay (Pgt;0.05). Conclusion Using low-dose dexamethasone after operation anastomotic colorectal resection in patients with colorectal cancer is safe and may have potential to enhance recovery after operation.
ObjectiveTo observe the effects of bulbar subconjunctival and periocular injection of dexamethasonone on blood glucose levels of type 1 diabetic mellitus (T1DM)rats. Methods80 healthy adult male Sprague-Dawley rats were randomly divided into GroupⅠ(n=40) and GroupⅡ(n=40). GroupⅠrats received intraperitoneal (IP) injection of streptozotocin to induce T1DM model, while GroupⅡrats received IP injection of citrate buffer solution and was the control group.GroupⅠrats and GroupⅡrats were further divided into four subgroups:A (n=10), a (n=10), B (n=10), and b (n=10). Subgroup-A rats received bulbar subconjunctival injection of dexamethasone, subgroup-a rats received bulbar subconjunctival injection of saline, subgroup-B rats received periocular injection of dexamethasone, subgroup-b rats received periocular injection of saline. After the injection, rats were fasted but could drink water. Tail vein blood samples were collected and the blood glucose level was measured by glucose monitor. ResultsAfter modeling, the blood glucose level of GroupⅠand GroupⅡrats was(9.31±1.79) mmol/L and (5.72±0.80) mmol/L respectively, the difference was statistically significant (P < 0.05). The blood glucose level of GroupⅠrats reached the peak in 3h after injection. In 6-24 h after injection, the blood glucose level of GroupⅠA rats was obviously increased than that of the blood glucose level of Group Ia rats and the difference was statistically significant (P < 0.05). In 3-24 hours after injection, the blood glucose level of GroupⅠB rats was obviously increased than that of the blood glucose level of GroupⅠb rats and the difference was statistically significant (P < 0.05). Comparing the blood glucose level during different injection time between GroupⅠA rats and GroupⅠB rats, between GroupⅠa rats and GroupⅠb rats, the difference was not statistically significant (P > 0.05). In 3-24 hours after injection, the blood glucose level of GroupⅡA rats was obviously increased than that of the blood glucose level of GroupⅡa rats and the difference was statistically significant (P < 0.05); the blood glucose level of GroupⅡB rats was obviously increased than that of the blood glucose level of GroupⅡb rats and the difference was statistically significant (P < 0.05). Comparing the blood glucose level during different injection time between GroupⅡA rats and GroupⅡB rats, between GroupⅡa rats and GroupⅡb rats, the difference was not statistically significant (P > 0.05). ConclusionBulbar subconjunctival injection and periocular injection of dexamethasone could both increase the blood glucose of TIDM rats, but these two injection methods had no differences on the blood glucose level.
Objective To investigate the effect of bone morphogenetic protein 2 (BMP-2) and dexamethason (DXM) on proliferation and differentiation of human dental pulp cellsin vitro. Methods Primary human dental pulp cells were cultured in vitro by tissue culture method. The 3rd generation cells were used to identify cell phenotype for vimentin and cytokeratin by immunocytochemistry staining. The 3-5 generations of human dental pulp cells were randomly divided into 4 groups: 100 ng/mL BMP-2 (group A), 1×10–8 mol/L DXM (group B), and both 100 ng/mL BMP-2 and 1×10–8 mol/L DXM (group C) were added; neither BMP-2 nor DXM was added in group D as control group. The cell growth curve was drawn at 1, 3, 5, and 7 days after culture. The expressions of osteo/dentanogenic genes including alkaline phosphatase (ALP), dentin sialophoshoprotein (DSPP), and dentin matrix protein 1 (DMP-1) were detected by RT-PCR analysis at 5 and 7 days after culture, the ratio between the positive staining area and the total area by ALP staining at 14 days, and absorbance (A) value at 562 nm by alizarin red staining at 21 days after culture. Results Human dental pulp cells were successfully isolated and cultured, which were long fusiform and showed a positive reaction for vimentin and a negative reaction for cytokeratin. The growth curve indicated that cells increased with the extending of incubation time, reached a peak at 5 days, then reduced at 7 days to the level at 3 days. At 5 days after culture, the cells were significantly more in groups A, B, and C than group D (P<0.05), in group C than group A (P<0.05), and in group A than group B (P<0.05). RT-PCR analysis showed that the mRNA expressions of ALP, DSPP, and DMP-1 at 5 days were significantly higher in groups A, B, and C than group D (P<0.05), and in group C than groups A and B (P<0.05), but no significant difference was found between groups A and B (P>0.05); the mRNA expression of DSPP in groups A, B, and C was significantly higher than that in group D (P<0.05), but there was no significant difference in mRNA expressions between other groups at 7 days (P>0.05). At 14 days, positive staining in varying degrees was observed in each group, especially in group C; the ratio between the positive staining area and the total area was significantly higher in group C than groups A, B, and D (P<0.05), and in groups A and B than group D (P<0.05), but there was no significant difference between groups A and B (P>0.05). At 21 days, there were a variety of mineralized nodules in groups A, B, and C in nonuniformly scattered or clustered distribution, but no mineralized nodules were observed in group D. TheA values of mineralized nodules showed significant difference between groups (P<0.05). Conclusion BMP-2 may be more effective in promoting proliferation of human dental pulp cells than DXM. Combined application of BMP-2 and DXM can remarkably promote the proliferation and differentiation of human dental pulp cells.
OBJECTIVE: To investigate the effects of dexamethasone on the proliferation and differentiation of bone marrow stromal cells(MSC). METHODS: MSC were isolated and cultured in vitro. After treatment with different concentrations of dexamethasone (0, 10-10, 10-9, 10-8, 10-7 and 10-6 mol/L), the proliferation and alkaline phosphatase (ALP) activity of MSC were measured to evaluate the effect of dexamethasone on the biological characteristics of MSC. RESULTS: Dexamethasone inhibited cell proliferation. With the increase of concentration of dexamethasone, the effect was enhanced, which was more significant when the concentration of dexamethasone was over 10-8 mol/L. At the same time, dexamethasone promoted the activity of ALP. This effect was enhanced with the increase of concentration of dexamethasone, but the alteration was small when the concentration of dexamethasone was over 10-8 mol/L. The effects increased with the time. The activity of ALP was enhanced 2 to 4 times with the dexamethasone for 6 days. CONCLUSION: Dexamethasone inhabit the proliferation of MSC, while induce them to differentiate into osteoblasts. The appropriate concentration of dexamethasone was 10-8 mol/L.
Objective To investigate the role of IFN-γ in suppressing bleomycin-induced pulmonary fibrosis in rats.Methods Seventy-five SD rats were randomly divided into five groups (15 rats in each group)，ie.a normal group，a bleomycin-induced pulmonary fibrosis model group，a dexamethasone-treated group，a high-dose IFN-γ-treated group (150 000 U/kg) and a low-dose IFN-γ-treated group (50 000 U/kg).Five rats in each group were randomly killed in 7th day，14th day and 28th day after relative treatment respectively，and lung tissue samples were harvested for histopathology study.HE and Masson staining were used to determine the extent of alveolus inflammation and pulmonary fibrosis respectively.Histoimmunochemical method were adapted to determine protein levels of TGF-β1，CTGF，type Ⅰcollagen and type Ⅲ collagen in pulmonary tissues.Results Histopathological study showed that treatment with either dexamethasone or IFN-γ (both high dose and low dose) remarkably meliorated the extent of alveolus inflammation and suppressed pulmonary fibrosis (compared with model group，all Plt;0.05).Histoimmunochemical study suggested that both dexamethasone and IFN-γ could inhibit the expression of TGF-β1，CTGF，type Ⅰand type Ⅲ collagen (compared with model group，all Plt;0.05)，and the suppression of TGF-β1，type Ⅰand type Ⅲ collagen expression was more obvious in high-dose IFN-γ-treated group than those in low-dose group (Plt;0.05).Conclusions INF-γ possesses apparent anti-fibrosis effect that is similar to dexamethasone but with less side effect.Such effect may resulted from reduced production of type Ⅰand type Ⅲ collagen through expression inhibition of cytokines such as TGF-β1 and CTGF.
Objective To investigate the effect of dexamethasone, recombinant human fibroblast growth factor (rhFGF) and recombinant human bone morphogenetic protein 2 (rhBMP-2) on the proliferation and differentiation of marrow stromal stem cells (MSCs) for their further application in tissue engineering. Methods MSCs were isolated and cultured in vitro, and then exposed to different dose of dexamethasone (10-8 mol/L,10-7 mol/L,10 -6 mol/L), rhFGF (50 ng/ml,200 ng/ml,500 ng/ml) and rhBMP-2 (50 ng/ml,500 ng/ml,1 000 ng/ml) respectively. The total protein and alkaline phosphatase (ALP) activity of each group was measured on 4th and 7th day. Results Exposure of MSCs with 10-6mol/L dexamethasone inhibited protein synthesis without obvious effects on ALP expression. The application of rhFGF significantly promoted cell proliferation but inhibited ALP activity. In comparison, ALP expression was significantly enhanced by treatment of rhBMP-2 at concentration of 500 ng/ml，1 000 ng/ml. Conclusion The exposure of dexamethasone as well as rhBMP-2 to MSCs with an appropriate concentration promotes osteogenic expression without reverse effects on cell proliferation, which indicates the great potential value in cell-based strategy of bone tissue engineering.