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AIM:To discuss the effects of different concentrations of tetramethylpyrazine (TMP), an active constituent of Chinese herb, on damaged Shandonghuman corneal epithelial cell (SDHCEC) induced by hydrogen peroxide.METHODS:We detected the combined effects of TMP with concentrations ranging from 4 mg/mL to 0.03 mg/mL and 800 μM hydrogen peroxide on SDHCEC. The methyl thiazolyl tetrazolium (MTT) assay was processed at 3, 6 and 12h separately while the detection of cell apoptosis at 6h only by flow cytometry.RESULTS:The viability of SDHCEC with 0.5 mg/mL, 0.25 mg/mL, 0.125 mg/mL and 0.06 mg/mL TMP joint with 800 μM hydrogen peroxide at 3h and 6h was significantly higher than that with 800 μM hydrogen peroxide only, P＜0.05. However, except 0.25 mg/mL, TMP with other concentrations joint with 800 μM hydrogen peroxide at 12h could not significantly inhibit decreased SDHCEC viability induced by 800 μM hydrogen peroxide. At 12h, TMP of 0.5 mg/mL, 0.25 mg/mL, 0.125 mg/mL and 0.06 mg/mL could significantly inhibit SDHCEC early apoptosis induced by 800 μM hydrogen peroxide, most remarkable at 0.25 mg/mL TMP, P＜0.05.CONCLUSION:Our results suggested that hydrogen peroxide can induce apoptosis related damage to SDHCEC. TMP can protect SDHCEC from the damage, and the protective effects may be associated with its anti-apoptosis mechanism.

The phytohormone gibberellin acid (GA) controls many aspects of plant development. In this study, we identified proteins that are differentially expressed between the rice (Oryza sativa L.) GA-deficient cultivar, Aijiaonante, and its parental line, Nante. Proteins were extracted from rice leaf sheath and examined by 2DGE. Among more than 1200 protein spots reproducibly detected on each gel, 29 were found to be highly up-regulated by GAs in Nante, and 6 were down-regulated by GAs in Aijiaonante. These 35 proteins were identified by MALDI-TOF MS and were classified into three groups based on their putative function in metabolism, stress/defense processes and signal transduction. These data suggest that metabolic pathways are the main target of regulation by GAs during rice development. Our results provide new information about the involvement of GAs in rice development.

Background Dry eye (DE) is a common eye disease, and appropriate animal models are essential to explore the pathogenesis and therapy of DE. In this study, we aimed to establish rabbit models by three methods. Methods In group A, the lacrimal gland, Harderian gland, and nictitating membrane of the left eyes were surgically removed. In group B, the bulbar conjunctiva of the left eyes was burned with 50% trichloroacetic acid. In group C, both methods above were used. The right eyes served as normal controls. The Schirmer I test (SIt), fluorescein staining, and impression cytology were evaluated at baseline and on days 28, 42, and 56. Results Both the SIt and goblet cell density were significantly lower in operated eyes compared to the control eyes, while the corneal fluorescein staining scores in the operated eyes were significantly higher than in the control eyes on days 28, 42, and 56 (p < 0.05, p < 0.01 or p < 0.001). The SIt and goblet cell densities in groups B and C were significantly lower than group A on days 28, 42, and 56 (p < 0.05, p < 0.01 or p < 0.001). In addition, the corneal fluorescein staining scores in group C were significantly higher than either group A or group B on days 28, 42, and 56, while fluorescein staining scores were higher in group B than group A on days 42 and 56 days (p < 0.05, p < 0.01 or p < 0.001), with mean score 3.8 ± 1.30 (group A), 7.4 ± 1.14 (group B) and 10.8 ± 1.30 (group C) on day 56. Conclusions Results suggest that three separate DE models, with mild, moderate, and severe manifestations of DE, could be stably established, in which conjunctival goblet cells took an important role.