BACKGROUND/OBJECTIVES: Bitter taste receptors are taste signaling pathway mediators, and are also expressed and function in extra-gustatory organs. Skin aging affects the quality of life and may lead to medical issues. The purpose of this study was to better understand the anti-skin aging effects of bitter taste receptors in D-galactose (D-gal)-induced aged human keratinocytes, HaCaT cells.MATERIALS/METHODS: Expressions of bitter taste receptors in HaCaT cells and mouse skin tissues were examined by polymerase chain reaction assay. Bitter taste receptor was overexpressed in HaCaT cells, and D-gal was treated to induce aging. We examined the effects of bitter taste receptors on aging by using β-galactosidase assay, wound healing assay, and Western blot assay. RESULTS: TAS2R16 and TAS2R10 were expressed in HaCaT cells and were upregulated by D-gal treatment. TAS2R16 exerted protective effects against skin aging by regulating p53 and p21, antioxidant enzymes, the SIRT1/mechanistic target of rapamycin pathway, cell migration, and epithelial-mesenchymal transition markers. TAS2R10 was further examined to confirm a role of TAS2R16 in cellular senescence and wound healing in D-gal-induced aged HaCaT cells. CONCLUSIONS Our results suggest a novel potential preventive role of these receptors on skin aging by regulating cellular senescence and wound healing in human keratinocyte, HaCaT.

Background: The purpose of this study is to analyze whether there is a change in patterns of medical use among those likely to be converted their health insurance qualifications when the family support rule is alleviated. There is no empirical analysis that converting health insurance qualification will affect the increase in medical use. Methods: For analysis, data were extracted from the national health insurance eligibility and medical care database. To identify analysis targets similar to that of medical aids’ characteristics among health insurance coverage, we compared income, property level, and medical use patterns through basic statistical analysis and used a difference-in-difference (DID) analysis to estimate the net effect of changes in medical use following the change of qualifications. Results: The main results are as follows. The results show that those who are under the 5% income group (1st income group) of health insurance coverage are the most similar to the medical aids group. DID analysis shows that changes in the medical use of people who maintain their national insurance qualification and who are not. As a results, the number of hospitalized days of converting group was reduced by 3.5 days while outpatient days were increased by 1.8 days. Conclusion As a result, there was not much difference in the patterns of medical use for the under 5% income group who are likely to be eligible for expanded medical aids when the family support rule is alleviated. In addition, more than 30% of them are in arrears with their health insurance premiums, causing inconvenience in using medical services. These findings suggest the need of abolishing the criteria obligated to support family, and great efforts should be made to contribute to non-paid poor and remove their medical blind spot.