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OBJECTIVE:To optimize the formulation of Methotrexate thermosensitive hydrogels,and to study the in vitro re-lease property of it. METHODS:Taking PLGA-PEG-PLGA as matrix and mannitol as viscosity modifiers,Methotrexate thermosen-sitive hydrogels were prepared. Using the absolute value of the deviation of gelation temperature between 35 ℃,its formulation was optimized by orthogonal test using the concentrations of PLGA-PEG-PLGA,methotrexate and mannitol as factors. The dialysis bag method was used to investigate accumulative release rate of Methotrexate thermosensitive hydrogels and methotrexate solution within 336 h in vitro. RESULTS:The optimal formulation was as PLGA-PEG-PLGA of 20%,methotrexate of 0.10% and mannitol of 0.10%;gelation temperature were 35.1,35.0,35.0℃. The average drug-loading rate was more than 90%. 12 d accumulative re-lease rate was more than 90%(r=3). Methotrexate solution has been substantially completely relased within 240 h. CONCLU-SIONS:Methotrexate thermosensitive hydrogels with sustained-release are prepared successfully,and the preparation technology is simple and practical.
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Objective:To investigate the radiosensitizing effect of three flavonoids on ovarian cancer SKOV3 cells under hypoxia. Methods:The SKOV3 cells were divided into normoxic group and hypoxic group. The hypoxic SKOV3 cellular model in vitro was es-tablished and tested by measuring the expression profile of HIF-1αprotein in SKOV3 cells. Colony-forming assay was used to detect the radiosensitivity of normoxic and hypoxic SKOV3 cells. The cytotoxicity and radiosensitizing effects of flavonoids were evaluated on the basis of cell death and MTT assay. Results:The Western blot results showed that the gray intensity ratio of HIF-1α/β-Actin in hypoxia group was significantly higher than that in normoxia group (1. 068>0. 117). Radiosensitivity of hypoxic SKOV3 cells in hypoxia group was significantly lower than that in normoxia group. The survival rate of SKOV3 cells was decreased with the increase of concentration. When the concentration was increased, D0 and Dqin chrysin group and quercetin group were significantly decreased (P0. 05). The overall radiobiological parameters of hypoxia group were higher than those of normoxia group. Conclusion: Hypoxia can induce the expression of HIF-1α in SKOV3 cells, which results in the decrease of radiosensitivity. Chrysin and quercetin can enhance the radiosensitivity of SKOV3 cells, and the enhancement is significant under hypoxia, while breviscapine is without such effect. The radiosensitizing effect may be achieved by the level decrease of HIF-1α in SKOV3 cells and inhibition of DNA damage repair.
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Triamcinolone acetonide is one of adrenocorticotropic hormones. Its anti-inflammatory and anti-allergic effects are strong and lasting. However, due to its poor water solubility and systemic side effects, researchers try to transform and create its new formula constantly. The paper reviewed the research progress in new formula of triamcinolone acetonide at home and abroad in recent years, including solid dosage forms, emulsion, particle dispersion system and the other new formula which have been researched in or-der to provide information for the improvement of bioavailability and safety.
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Objective To prepare triamcinolone acetonide acetate(TAA)thermosensitive hydrogel for intra-articular injection,and to investigate its release in vitro. Methods TAA suspending thermosensitive hydrogel was prepared by using poly lactic-co-glycolic acid(PLGA)-polyethylene glycol(PEG)-PLGA as gel matrices,xanthan gum as suspending agent and NaCl as flocculant. It was evaluated preliminarily by determining its contents and its in vitro release. Results The best compositions for preparation of TAA suspending thermosensitive hydrogel were 25% PLGA-PEG-PLGA,0.05% xanthan gum, 0.9% NaCl and 4 mg·mL-1 TAA.The gelation temperature was 35.3 ℃ .The average recovery was(98.98±0.31)%. By the method of membraneless dissolution,the accumulative drug release was up to 83. 31% at 16 days. The drug release followed Ritger-Peppas methematical model. Conclusion The TAA thermosensitive hydrogel with obviously sustained release is expected to become a new drug delivery system for intra-articular injection.
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Objective To detect content of 4-hydroxy-3-methoxy benzoic acid by RP-HPLC and observe the inhibitory effect of phloroglucinol on catecholamine-O-methyl transferase (COMT). Methods This study used the principle of 3,4-dihydroxy benzoic acid transforming to 4-hydroxy-3-methoxy benzoic acid under COMT’ s catalytic action. COMT (20 μL) was extracted from mouse liver homogenate. In a reaction system,10 μL catecol (1í10-3 mol·L-1 ) and 10 μL phloroglucinol (5í10-3 , 1í10-3 and 2í10-4 mol·L-1 ,respectively) were added. Products were determined by RP-HPLC to analyze effects of 4-hydroxy-3-methoxy benzoic acid on COMT. Results Phloroglucinol had inhibitory effect on COMT activity at concentrations of 5í10-3 mol·L-1 ,1í10-3 mol·L-1 and 2 í10-4 mol ·L-1 ,with the inhibition rate being 25. 3% ,17. 6% and 8. 9% ,respectively. Conclusion Phloroglucinol has an inhibitory effect on COMT activity,which is weaker than the effect of catechol of the same concentration.