This study was designed to establish an atopic dermatitis (AD) model using MC903 and was conducted to find out the optimal challenge concentration that can cause dermatitis symptoms enough to be experimentally verified while reducing adverse effects such as weight loss. MC903 was treated at concentrations of 2, 3, and 4 nmol/day, and evaluation of skin surface symptoms, water contents, histopathological changes, body weight changes, and spleen/body weight ratio was conducted. In addition, the expression level of thymic stromal lymphopoietin (TSLP) was also observed. In our results, MC903 induced AD skin lesions such as erythema, scab and fissure and lowered skin moisture level significantly. In addition, water holding capacities in the 3 or 4 nmol groups were diminished significantly compared to that in the control group. On the other hand, 4 nmol treatment induced a weight loss of up to 20% compared to control group. Finally, a higher level of TSLP expression was observed in the 3 nmol group than in the 2 nmol group or the 4 nmol group. Taken together, we propose a total 14-day protocol consisting of 3 days of sensitization (2 nmol/day) and 6 days of challenge (3 nmol/day).

Bisphosphonates, estrogen, and calcium supplements are commonly used medications for postmenopausal osteoporosis, but they are associated with various side effects such as vaginal bleeding, deep vein thromembolism, and breast cancer. In this study, we aimed to investigate the potential of a compound isolated from the roots of Oryza sativa L. to improve osteoporosis using an ovariectomized mouse model. We isolated and identified oryzativol A, a lignan compound, through chemical analysis of an ethanol extract using a bioassay-guided fractionation protocol. We also examined the metabolism, clearance, and CYP enzyme activity of oryzativol A, and found that it showed plasma stability of over 80% at all analysis times, and indicating a low likelihood of inactivation or excretion by the CYP3A4 enzyme. Our results showed that the high-dose group of oryzativol A exhibited a significant increase in bone mineral density compared to the control group. Although the ALP concentration did not differ significantly compared to the control group, it showed a tendency to increase in the high-dose group of oryzativol A. Furthermore, the abnormal ratio of serum Ca/P, caused by osteoporosis, was improved to a level closer to that of the normal group as the dosage of oryzativol A increased. Taken together, these findings suggest that oryzativol A is stable in vivo and has potential as a therapeutic agent for osteoporosis, particularly when administered in high doses.

Essential oils and aromatherapy have traditionally been used for the treatment of anxiety and depression with few side effects. This study aimed to investigate the effects of essential oils from six herbal prescriptions known to be effective in treating anxiety and depression in Korean medicine. The neuroprotective and anti-neuroinflammatory effects of six essential oils, including Gamisachil-tang (GMSCT), Guibi-tang (GBT), Sihogayonggolmoryeo-tang (SYM), Danchisoyosan (DCSYS), Sihosogansan (SHSGS), and Soyosan (SYS), were examined in PC12 and BV2 cells. In corticosterone (CORT)-stimulated PC12 cells, all six essential oils ameliorated the CORT-induced decrease in cell viability at a concentration of 10 ㎍/ml. GMSCT, GBT, and SHSGS recovered CORT-induced cytotoxicity at concentrations of 1 ㎍/ml and 10 ㎍/ml. In lipopolysaccharide (LPS)-stimulated BV2 cells, GBT (10 ㎍/ml) decreased interleukin (IL)-1β production, whereas SHSGS (1 ㎍/ml) inhibited tumor necrosis factor (TNF)-α production. In the MK-801-induced anxiety in zebrafish, electroencephalogram (EEG) assessment indicated that GMSCT and SHSGS induced recovery in the delta and beta power densities and reduced theta/beta and delta/beta ratios. DCSYS and SYS decreased theta power density and theta/beta ratio, whereas GBT and SYM showed no effects on EEG signals. In the tail suspension test (TST) in mice, GBT, DCSYS, SHSGS, and SYS exhibited antidepressant-like effects by decreasing immobility time. These results suggest that the essential oils from the six herbal prescriptions, except SYM, may have beneficial effects on anxiety and/or depression. Further studies should be conducted to investigate the molecular signaling pathways that mediate the effects of these essential oils on anxiety and depression.