Heat shock protein (HSP) induction confers protection against diverse forms of cellular and tissue injury. However, the mechanism by which HSP exerts cytoprotective effects is unclear. Because HSP induction inhibits genetic expression of pro-inflammatory cytokines, the transcription of which is dependent on NF-κB activation, we explored the relationship between the anti-inflammatory effect of HSP induction and the NF-κB/IκBα pathway. Both HS and sodium arsenite treatment increased HSP70 expression time dependently at mRNA and protein levels. Prior induction of HSP suppressed cytokine-induced IL-8 and TNF-α expression at both mRNA and protein levels. Although HSP induction did not affect total cellular expression of NF-κB, TNF-α-induced increase in NF-κB-DNA binding activity and nuclear translocation of the p65 subunit of NF-κB were inhibited by prior HSP induction, suggesting that activation of NF-κB was blocked. Cytokine-induced IκBα phosphorylation and its degradation were blocked in HSP-induced cells. Immune complex kinase assays demonstrated that TNF-α induced increase in IκB kinase activity was suppressed by prior HSP induction. These results suggest that the anti-inflammatory effect of HSP induction in respiratory epithelial cells is related to stabilization of IκBα, possibly through the prevention of IκB kinase activation, which thereby inhibits activation of NF-κB.

To evaluate the prevalence of and risk factors for dry eye disease (DED) in an elderly Korean population.Methods: This population-based study in Yongin, Korea, included 657 individuals 65 years or older randomly selected from an official household registration database. Dry eye symptoms were assessed using a 6-item questionnaire, and DED was defined as having 1 or more dry eye symptoms often or all the time. Dry eye tests, including the Schirmer test, tear film break-up time measured using fluorescein, cornea fluorescein staining, and examination for meibomian gland dysfunction, were performed. Results:The crude prevalence of DED was 30.3%, and the age-, sex-, and region (urban vs rural)-adjusted preva-lence was 33.2%. Women (P=.01) and urban dwellers (P =.001) were more likely to have DED. Of those with DED, 85.1% had tear film break-up time of 10 seconds or less, 54.1% had meibomian gland dysfunction, 39.2% had a fluorescein score of 1 or greater, and 32.8% had a Schirmer test score of 5 mm or less. A low Schirmer score was correlated with increased prevalence of DED, although sensitivity was low.Conclusions: Dry eye disease is common in elderly Koreans; female sex and living in an urban region were strongly correlated with its frequency. We also noted a positive correlation between low Schirmer test scores and symptom-based DED.

Depression was associated with DED symptoms in subjects with normal or mildly reduced tear production.

No abstract