Cnidii Rhizoma is the dried root stem of Cnidium officinale Makino. Cnidii Rhizoma (CR) has been used to treat menstrual irregularity, menstrual pain, and menopause in Korea. However, the effects and mechanisms of CR on RANKL-induced osteoclastogenesis pathway remain to be elucidated. In this study, we investigated the effects of CR on the inhibition of bone resorption of osteoclast and its mechanism RANK signaling pathway. The anti-osteoclastogenesis of water extract of CR was measured using RAW 264.7 cell. Tartrate-resistant acid phosphatase (TRAP) assay, pit assay, reverse transcription polymerase chain reaction (RT-PCR) and western blot were performed. Moreover, the effects of CR were determined with an in vivo model using ovariectomized (OVX) rats. CR extract suppressed osteoclastogenesis, its activity and bone resorption activity through decreasing gene of osteoclast-related such as nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), c-Fos, etc. Moreover, CR extract prevented the bone loss in OVX rats. These results show that CR has a positive effect on menopausal osteoporosis by suppressing osteoclastogenesis.

Atopic dermatitis (AD) and stress create a vicious cycle: stress exacerbates atopic symptoms, and atopic disease elicits stress and anxiety. Targeting multiple pathways including stress and allergic inflammation is, therefore, important for treating AD. In this study, we investigated the remedial value of Polygala tenuifolia Willd. (PTW) for treating immobilization (IMO) stress-exacerbated atopy-like skin dermatitis and its underlying mechanism. Trimellitic anhydride (TMA) was applied to dorsal skin for sensitization and subsequently both ears for eliciting T-cell-dependent contact hypersensitivity in mice, which underwent 2 h-IMO stress and PTW administration for the latter 6 and 9 days in the ear exposure period of TMA, respectively. To elicit in vitro degranulation of human mast cell line-1 (HMC-1), 10 µM substance P (SP) and 200 nM corticotrophin-releasing factor (CRF) were sequentially added with 48 h-interval. PTW extract (500 µg/mL) was added 30 min before CRF treatment. IMO stress exacerbated TMA-induced scratching behavior by 252%, and increased their blood corticosterone levels by two-fold. Treatment with 250 mg/kg PTW significantly restored IMO stress-exacerbated scratching behavior and other indicators such as skin inflammation and water content, lymph node weights, and serum histamine and immunoglobulin E (lgE) levels. Furthermore, it also reversed TMA-stimulated expression of tumor necrosis factor (TNF)-α and interleukin (IL)-4 mRNAs in ear tissues. PTW significantly inhibited SP/CRF-stimulated degranulation of HMC-1 cells, subsequent tryptase secretion, and protein kinase A (PKA) activity. PTW also selectively inhibited p38 mitogen-activated protein kinase (MAPK) phosphorylation in SP/CRF-treated HMC-1 cells. PTW significantly inhibited HMC-1 cell degranulation and alleviated IMO stress-exacerbated atopic dermatitis symptoms by modulating the PKA/p38 MAPK signaling pathway.

(1) Background: Atopic dermatitis (AD) is a multifactorial chronic allergic skin disease. Gastrointestinal (GI) functions have been suggested to be associated with its incidence or severity. As modulators of the gut–skin axis, gut microbes might affect the pathophysiology of AD. (2) Methods: We divided a cohort of patients with AD according to their GI symptoms as follows: AD with epigastric fullness (ADwEF), AD with epigastric rigidity (ADwER), and AD without GI symptoms (ADw/oGI). The gut microbial profiles were analyzed using 16S rRNA amplicon sequencing. (3) Results: The microbiota of the ADwER group showed low diversity indices in richness and evenness and formed a separate cluster to the other groups. In the ADwER group, the proportion of Bacteroides increased, while that of Prevotella decreased; functional pathways related to phosphotransferase systems were not abundant relative to those in the ADw/oGI group. Taken together, patients with AD with GI symptoms have a different microbiome from patients with simple AD. (4) Conclusions: In an exploratory study aimed at evaluating the relationship between AD and GI symptoms, the gut microbiome in patients with AD with GI symptoms differed from that in patients with simple AD, and this result could serve as a basis for further gut–skin axis studies.