Thomas Chu1, Nan-Lin Wu2, Chien-Yu Hsiao3, Hsin-Ju Li4, Tung-Yi Lin5, Cheng-Hung Ku6, Chi-Feng Hung7. 1. Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City, 22060, Taiwan; School of Medicine, Wayne State University, Detroit, 48201, USA. Electronic address: tchu@wayne.edu. 2. Department of Medicine, Mackay Medical College, New Taipei City, 25245, Taiwan; Department of Dermatology, MacKay Memorial Hospital, Taipei, 10491, Taiwan; Mackay Junior College of Medicine, Nursing, and Management, New Taipei City, 11260, Taiwan. Electronic address: alvin.4200@mmh.org.tw. 3. Department of Nutrition and Health Science, Chang Guang University of Science and Technology, Taoyuan, 33303, Taiwan; Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, 33303, Taiwan. Electronic address: mozart@gw.cgust.edu.tw. 4. Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, 24205, Taiwan. Electronic address: 144733@mail.fju.edu.tw. 5. Department of Chinese Internal Medicine, Keelung Chang Gung Memorial Hospital, Keelung, 20401, Taiwan. Electronic address: tungyi30@cgmh.org.tw. 6. Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, 24205, Taiwan. Electronic address: k8819576@hotmail.com. 7. Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, 24205, Taiwan; MS Program Transdisciplinary Long Term Care, Fu Jen Catholic University, New Taipei City, 24205, Taiwan; Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Pharmacy Department, Cathay General Hospital, Taipei, 10630, Taiwan; Ph.D. Program in Pharmaceutical Biotechnology, Fu Jen Catholic University, New Taipei City, 24205, Taiwan. Electronic address: skin@mail.fju.edu.tw.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Numerous epidemiological and clinical studies have demonstrated the protective role of dietary isoflavones against development of several chronic diseases. ISO-1, one fraction of isoflavone powders derived from soybean cake, is reported to attenuate inflammation and photodamage. AIM OF THE STUDY: Contact dermatitis is a common inflammatory skin disease, which accounts for most occupational skin disorders. Instead of oral administration, we aimed to explore the effects of topical ISO-1 application on contact dermatitis by using 2,4-dinitrochlorobenzene (DNCB)-stimulated HaCaT keratinocytes and DNCB-induced mouse dermatitis as models. MATERIALS AND METHODS: In the in vitro study, we first evaluated the biologic effects of DNCB on HaCaT keratinocytes. HaCaT keratinocytes were treated with 2,4-dinitrochlorobenzene (DNCB), and cell viability was measured by MTT assay. Then, we detect the prominent induction of IL-8 mRNA expression after DNCB and ISO-1 treatment by reverse transcription polymerase chain reaction (RT-PCR), and release of IL-8 from HaCaT keratinocytes was measured by ELISA assay. HaCaT keratinocytes were pretreated with ISO-1 and then treated with DNCB, phosphorylation of JNK, p38, ERK and IκBα was analyzed by western blot. In the in vivo study, the hairless mice were used for an induced contact dermatitis model. The surface changes in the dorsal skin after DNCB and ISO-1 treatment were recorded using photography, and TEWL, erythema were measured using an MPA-580 cutometer. Blood was also collected from mice for measurement of white blood cell counts. RESULTS: Results showed ISO-1 inhibited DNCB-induced IL-8 production and also suppressed DNCB-induced phosphorylation of JNK and p38, and IκBα in HaCaT. In the animal model of DNCB-induced contact dermatitis, topical ISO-1 treatment significantly decreased DNCB-induced erythema and transepidermal water loss (TEWL) in mouse skin. ISO-1 also reduced DNCB-induced skin thickening and increase of white blood cell count. CONCLUSIONS: ISO-1 is promising for improvement of DNCB-induced inflammation and skin barrier impairment, suggesting the potential application of topical ISO-1 for inflammatory dermatoses.
ETHNOPHARMACOLOGICAL RELEVANCE: Numerous epidemiological and clinical studies have demonstrated the protective role of dietary isoflavones against development of several chronic diseases. ISO-1, one fraction of isoflavone powders derived from soybean cake, is reported to attenuate inflammation and photodamage. AIM OF THE STUDY: Contact dermatitis is a common inflammatory skin disease, which accounts for most occupational skin disorders. Instead of oral administration, we aimed to explore the effects of topical ISO-1 application on contact dermatitis by using 2,4-dinitrochlorobenzene (DNCB)-stimulated HaCaT keratinocytes and DNCB-induced mousedermatitis as models. MATERIALS AND METHODS: In the in vitro study, we first evaluated the biologic effects of DNCB on HaCaT keratinocytes. HaCaT keratinocytes were treated with 2,4-dinitrochlorobenzene (DNCB), and cell viability was measured by MTT assay. Then, we detect the prominent induction of IL-8 mRNA expression after DNCB and ISO-1 treatment by reverse transcription polymerase chain reaction (RT-PCR), and release of IL-8 from HaCaT keratinocytes was measured by ELISA assay. HaCaT keratinocytes were pretreated with ISO-1 and then treated with DNCB, phosphorylation of JNK, p38, ERK and IκBα was analyzed by western blot. In the in vivo study, the hairless mice were used for an induced contact dermatitis model. The surface changes in the dorsal skin after DNCB and ISO-1 treatment were recorded using photography, and TEWL, erythema were measured using an MPA-580 cutometer. Blood was also collected from mice for measurement of white blood cell counts. RESULTS: Results showed ISO-1 inhibited DNCB-induced IL-8 production and also suppressed DNCB-induced phosphorylation of JNK and p38, and IκBα in HaCaT. In the animal model of DNCB-induced contact dermatitis, topical ISO-1 treatment significantly decreased DNCB-induced erythema and transepidermal water loss (TEWL) in mouse skin. ISO-1 also reduced DNCB-induced skin thickening and increase of white blood cell count. CONCLUSIONS:ISO-1 is promising for improvement of DNCB-induced inflammation and skin barrier impairment, suggesting the potential application of topical ISO-1 for inflammatory dermatoses.