2019, Vol.13, No.1

Journal of Alternatives to Animal Experiments 2023 KCI Impact Factor : 0.07

pISSN : 1975-9657
https://journal.kci.go.kr/ksaae

Skin is located on the outermost layer of body, which poses it to easy and frequent exposure to toxic chemicals, physical stimuli and environmental contaminants. Depending on the stimuli, outcomes of skin toxicity may differ, which include commonly observed, and evident skin reactions like skin burn, irritation, sensitization, phototoxicity, or photosensitivity. Less common reactions like pigmentary disorders, urticaria, and fibrosis can also occur. Effects of sunlight on the skin have been well established and with this, radiations with longer wavelength are gathering interest for their effects on the skin health. In this study, we investigated the effects of electromagnetic field (EMF) of LTE bandwidth, 1.742 GHz, SAR 6-8 W/kg on the skin by using an artificial human skin model. The results indicated that EMF exposure does not have much effect on epidermal cytotoxicity or obvious pigmentation in the skin, but it has a slight effect on skin epidermal integrity and melanocyte activation. The mechanism and the final outcome of EMF exposure should be further studied through more scientific studies and various molecular biochemical studies.

The Spectrophotometric direct peptide reactivity assay (Spectro-DPRA) is now in process for the development and validation of evaluation on skin-sensitizing chemicals. The cysteine peptides (Ac-RFAACAACOOH) and lysine peptides (Ac-RFAAKAA-COOH) is used for Spectro-DPRA. The objective of this study is to confirm the stability of cysteine and lysine peptides which are used for Spectro-DPRA through the storage conditions. We analyzed the stability of peptide using HPLC according to the conditions, such as storage temperature and storage period. The peptide powders of cysteine and lysine were stable on storage -80℃, for 6 and 12 month. And 10 mM stock peptides of cysteine and lysine were also stable on storage -70℃, for 1, 3 and 6 month. But 10 mM stock peptides of cysteine were denatured and not stable on storage -20℃, for 1 month. Taken together, peptides powder for Spectro-DPRA should be stored under -80℃, less than 12 month. And, 10 mM stock peptides should be also stored under -70℃, less than 6 month.

The concern of health and safety is growing due to increasing exposure of inhalable chemicals. However, there is no appropriate alternative testing method for assessing the hazard caused by inhalation exposure. The aim of this study is to establish respiratory 3-dimentional (3D) tissue model which can be applied for assessing the toxicity testing in Korea. First of all, respiratory 3D tissue model, SoluAirway™ was reconstituted by using human nasal mucosa. For evaluating its stability, the viability, Trans-Epithelial Electric Resistance (TEER), and histology was analyzed after delivered to 3 areas in Korea. Then, bleomycin (BLM) and polyhexamethylene guanidine phosphate (PHMG) which were known as toxic materials in pulmonary system were treated to various 3D tissue models to demonstrate applicability in evaluating chemical toxicity. The cytotoxicity and secretion of inflammatory cytokines was acquired with MTT and ELISA, respectively. The cell viability, TEER and integrity of the 3D tissue model which quality was controlled between products, had no significantly different values after delivery. The cytotoxicity of BLM and PHMG showed dose-dependently. Furthermore, the secretion of IL-8 was shown at the highest concentration of BLM and PHMG-p in SoluAirway™, not in EpiAirway™. When applied to KeraSkin™ which was a skin model, the secretion of IL-8 was declined. Taken together, these data showed that SoluAirway™ could be used as toxicity testing model for inhalable substances in Korea.