1. Department of Physiology, Seoul National University College of Medicine, Seoul 110-799, Korea.
2. Department of Dermatology, Seoul National University College of Medicine, Seoul 110-799, Korea.
3. Laboratory of Cutaneous Aging Research, Clinical Research Institute, Seoul National University Hospital, Seoul 110-799, Korea.
4. Institute of Dermatological Science, Seoul National University, Seoul 110-799, Korea.
5. Kidney Research Institute, Seoul National University, Seoul 110-799, Korea.