ABSTRACT
Objective To explore the protective effect of co-treatment with antioxidants 4-hydroxy-2,2,6,6-tetra-methylpiperidine 1-oxyl (TEMPOL) and reduced glutathione (GSH) in pancreatic injury induced by intermittent hypoxia (IH) in mice. Methods Fifty male C57BL/6J mice were randomly divided into control group(CON), IH group (IH), IH+TEM-POL group (IH+TEMPOL), IH+GSH group (IH+GSH) and IH+TEMPOL+GSH group (IH+TEMPOL+GSH). After successful-ly prepared animal model, the insulin resistance (IR) level, pancreatic malondialdehyde (MDA) level,superoxide dismutase (SOD) activity,glutathione reductase (GR) concentration and pancreatic β-cell apoptosis were detected in five groups. Re-sults The blood glucose level was significantly increased in IH group than that in CON group (P0.05). Conclusion The co-treatment with the antioxidant TEMPOL and GSH can obviously protect IH-induced pancreatic injury in mice. However, there was no significant protective effect of TEMPOL or GSH alone on pancreatic injury.
ABSTRACT
Objective To explore the establishment of skin photoaging model and the protective effects of nitroxide tempol on skin in guinea pig. Methods The guinea pig skin photoageing model was established by using solar-simulaten radiation (SSR). Dermal structure was observed with hematoxylin-eosin staining. The structure and expression of elastic fiber were analyzed by Weigert's staining. The uhrastructure of dermal fibroblasts and elastic fiber were observed by electron microscopy. Tempol was used before each exposure at the concentration of 5 mg/ml or 0. 5 mg/ml, and the protective effects of tempol on skin were assessed. Results After seventeen weeks' exposure, there was typical "solar elastosis" damage in the upper dermis. Mature elastic fibers were severely degraded and there was large amount of elastotic material accumulated in the upper dermis. Dermal fibroblasts appeared metabolically hyperactive and mitochondria in the cells were damaged. Some cells even broke up. Tempol at the concentration of 5 mg/ml or 0. 5 mg/ml could prevent photodamage of the photoageing model in the dermis, and Tempol at the concentration of 5 mg/ml had stronger protective effects. Conclusions Guinea pig can be applied as an useful animal model of skin photoageing. Antioxidant tempol has photoprotective effects on photodamage of the photoageing model in guinea pig and can be used as an anti-photoageing agent.
ABSTRACT
Objective To determine the effects of tempol(a nitroxide), in the exposure of ultraviolet-B (UVB), on cell proliferation, superoxide enzyme (SOD) activity, lipid peroxidation, and expression of matrix metalloproteinases (MMP)-1,MMP-3 in human foreskin fibroblasts in vitro. Methods Fibroblasts were irradiated by a single exposure of 36 seconds to 40 mJ/cm 2 UVB and at the same time incubated with, or without, tempol and detected twenty-four hours later. SOD activity and lipid peroxidation,as shown by accumulation malondialdehyde (MDA) were detected by biochemical assay. Expression of MMP-1 and MMP-3 (mRNA level) were examined by Semi-quantitative RT-PCR. Results 40 mJ/cm 2 UVB significantly inhibited cell proliferation rate to (84?8)% (P