AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were iso...AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were isolated from cadaver and cultured in vitro. They were challenged with UVB radiation and H2 O2 with and without zeaxanthin pretreatment. Cell viability, p38 and c-JUN NH(2)-terminal kinase(JNK) phosphorylation, IL-6, IL-8 and MCP-1 secretion and malondialdehyde(MDA) content were measured.RESULTS: Zeaxanthin had no measurable cytotoxicity on limbal or conjunctival epithelial cells when used at concentrations of 5 μg/mL and below. At 30 mJ/cm2 UVB, the pretreatment of zeaxanthin increased the percentage of live cells from 50% to 69%(P=0.01) and from 66% to 75%(P=0.05) for limbal and conjunctival epithelial cells, respectively. The concentrations of IL-6, IL-8 and MCP-1 in the culture medium reduced to 66%(for IL-6 and MCP-1)and 56%(for IL-8) of the levels without zeaxanthin. This was accompanied by reduced p38 and JNK protein phosphorylation. Pretreatment of zeaxanthin also reduced intracellular MDA content caused by H2 O2 stimulation from 0.86 μmol/L to 0.52 μmol/L(P=0.02) in limbal epithelial cells and from 0.96 μmol/L to 0.56 μmol/L in conjunctival epithelial cells(P=0.03). However, zeaxanthin did nothave significant effect on H2 O2-induced cell death in limbal or conjunctival epithelial cells.CONCLUSION: Zeaxanthin is an effective reagent in reducing the detrimental effect of UV-radiation and oxidative stress on ocular surface epithelial cells.展开更多
Dear Editor, Soybean can absorb and accumulate Cd from soils in their seed. Consumption, either directly or indirectly, of seed with high levels of Cd could be a human health concern, in 2001, the Codex Committee on ...Dear Editor, Soybean can absorb and accumulate Cd from soils in their seed. Consumption, either directly or indirectly, of seed with high levels of Cd could be a human health concern, in 2001, the Codex Committee on Food Additives and Contaminants of the Codex Alimentarius Commission established by the Food and Agriculture Organization and the World Health Organization proposed an upper limit of 0.2 mg kg-1 Cd con- centration in soybean grain （Codex Alimentrius Commission, 2001）. There are cultivar differences in seed Cd concentration in soybean and some cultivars accumulate high Cd concen- trations in seed when grown on Cd-contaminated soils （Arao et al., 2003）. These cultivars can exceed the proposed Codex upper limit. Cdal, a major gene controlling seed Cd accumu- lation, has been mapped on linkage group K by Jegadeesan et al. （2010）. The molecular mechanism of the Cdal gene underlyincl Cd accumulation in soybean seed is unknown.展开更多
Although the role of cathepsin C (Cat C) in inflammation is gradually being elucidated, its function in periapical periodontitis, which is one of the most common infectious diseases worldwide, has not been studied. Th...Although the role of cathepsin C (Cat C) in inflammation is gradually being elucidated, its function in periapical periodontitis, which is one of the most common infectious diseases worldwide, has not been studied. This study evaluated a surgically-induced model of periapical periodontitis in cathepsin C (Cat C) knock-down (KD) mice, which was constructed with a tetracycline operator, to evaluate the role of Cat C in the pathogenesis and progression of periapical periodontitis. Our results showed, for the first time, that there was a statistically significant increase in the expression of Cat C as periapical periodontitis progressed;this increase started from 1 week after surgery and reached a peak at 3 weeks after surgery, before gradually decreasing. The volume of periapical bone resorption in Cat C KD mice was significantly smaller than that in wild-type mice at 3 and 4 weeks after surgery (P<0.05). Inflammatory cell infiltration into the apical tissues of wild-type mice was also significantly higher than that of Cat C KD mice. The expression of receptor activator of nuclear factor-j B ligand (RANKL) in wild-type mice was also higher than that in Cat C KD mice. The difference in the number of osteoclasts in the apical area between the two groups was statistically significant after 2 weeks. Correlation analysis showed that there was a significant correlation between Cat C and RANKL expression (r= 0.835). Therefore, our data indicated that Cat C promoted the apical inflammation and bone destruction in mice.展开更多
基金Supported by the National Natural Science Foundation of China(No.81570829)
文摘AIM: To explore the protective effect of zeaxanthin on human limbal and conjunctival epithelial cells against UVradiation and excessive oxidative stress.METHODS: Human limbal and conjunctival epithelial cells were isolated from cadaver and cultured in vitro. They were challenged with UVB radiation and H2 O2 with and without zeaxanthin pretreatment. Cell viability, p38 and c-JUN NH(2)-terminal kinase(JNK) phosphorylation, IL-6, IL-8 and MCP-1 secretion and malondialdehyde(MDA) content were measured.RESULTS: Zeaxanthin had no measurable cytotoxicity on limbal or conjunctival epithelial cells when used at concentrations of 5 μg/mL and below. At 30 mJ/cm2 UVB, the pretreatment of zeaxanthin increased the percentage of live cells from 50% to 69%(P=0.01) and from 66% to 75%(P=0.05) for limbal and conjunctival epithelial cells, respectively. The concentrations of IL-6, IL-8 and MCP-1 in the culture medium reduced to 66%(for IL-6 and MCP-1)and 56%(for IL-8) of the levels without zeaxanthin. This was accompanied by reduced p38 and JNK protein phosphorylation. Pretreatment of zeaxanthin also reduced intracellular MDA content caused by H2 O2 stimulation from 0.86 μmol/L to 0.52 μmol/L(P=0.02) in limbal epithelial cells and from 0.96 μmol/L to 0.56 μmol/L in conjunctival epithelial cells(P=0.03). However, zeaxanthin did nothave significant effect on H2 O2-induced cell death in limbal or conjunctival epithelial cells.CONCLUSION: Zeaxanthin is an effective reagent in reducing the detrimental effect of UV-radiation and oxidative stress on ocular surface epithelial cells.
文摘Dear Editor, Soybean can absorb and accumulate Cd from soils in their seed. Consumption, either directly or indirectly, of seed with high levels of Cd could be a human health concern, in 2001, the Codex Committee on Food Additives and Contaminants of the Codex Alimentarius Commission established by the Food and Agriculture Organization and the World Health Organization proposed an upper limit of 0.2 mg kg-1 Cd con- centration in soybean grain （Codex Alimentrius Commission, 2001）. There are cultivar differences in seed Cd concentration in soybean and some cultivars accumulate high Cd concen- trations in seed when grown on Cd-contaminated soils （Arao et al., 2003）. These cultivars can exceed the proposed Codex upper limit. Cdal, a major gene controlling seed Cd accumu- lation, has been mapped on linkage group K by Jegadeesan et al. （2010）. The molecular mechanism of the Cdal gene underlyincl Cd accumulation in soybean seed is unknown.
基金This work was supported by the Open Research Fund Program of State Key Laboratory of Oral Disease,Sichuan Univeristy,China(SKLOD2019OF06).
文摘Although the role of cathepsin C (Cat C) in inflammation is gradually being elucidated, its function in periapical periodontitis, which is one of the most common infectious diseases worldwide, has not been studied. This study evaluated a surgically-induced model of periapical periodontitis in cathepsin C (Cat C) knock-down (KD) mice, which was constructed with a tetracycline operator, to evaluate the role of Cat C in the pathogenesis and progression of periapical periodontitis. Our results showed, for the first time, that there was a statistically significant increase in the expression of Cat C as periapical periodontitis progressed;this increase started from 1 week after surgery and reached a peak at 3 weeks after surgery, before gradually decreasing. The volume of periapical bone resorption in Cat C KD mice was significantly smaller than that in wild-type mice at 3 and 4 weeks after surgery (P<0.05). Inflammatory cell infiltration into the apical tissues of wild-type mice was also significantly higher than that of Cat C KD mice. The expression of receptor activator of nuclear factor-j B ligand (RANKL) in wild-type mice was also higher than that in Cat C KD mice. The difference in the number of osteoclasts in the apical area between the two groups was statistically significant after 2 weeks. Correlation analysis showed that there was a significant correlation between Cat C and RANKL expression (r= 0.835). Therefore, our data indicated that Cat C promoted the apical inflammation and bone destruction in mice.
