Effects of oleanolic acid on hair growth in mouse dorsal skin mediated via regulation of inflammatory cytokines.

Oleanolic acid (OA) is a pentacyclic triterpenoid with favourable physiological activity. It is widely distributed in more than 200 species of plants. OA has garnered significant interest because of its potential biological activities, such as antioxidant, bacteriostatic, and hair growth-promoting effects. To study the effect of OA on hair growth and related mechanisms, we investigated hair growth in mice with testosterone-induced androgenetic alopecia (AGA) that were treated with three different concentrations of OA. The antioxidant, bacteriostatic, and cytotoxic effects of OA were evaluated. We found that mice with testosterone-induced AGA treated with 1% or 0.5% OA showed significantly enhanced hair growth and increased vascular endothelial growth factor/glyceraldehyde-3-phosphate dehydrogenase ratio and levels of fibroblast growth factor receptor and insulin-like growth factor 1. Using an immunofluorescence staining assay, we demonstrated that ß-catenin, a key Wnt signalling transducer, was highly expressed in the OA-treated groups. These results suggest that OA may promote hair growth by stimulating hair matrix cell proliferation via the Wnt/ß-catenin pathway and lowering the levels of tumour necrosis factor-alpha, and transforming growth factor-beta 1, dihydrotestosterone, and 5α-reductase.

Characterization of antidiabetic effects of Dendrobium officinale derivatives in a mouse model of type 2 diabetes mellitus.

In this research, two sequential Dendrobium officinale water extracts (WDOE and WDOP1) were shown to significantly ameliorate type 2 diabetic mellitus (T2DM) in a mouse model. WDOP1 was identified as a glucomannan with a backbone of 1,4-linked Manp and 1,4-linked Glcp and an average molecular weight of 731 kDa. We also found that both WDOE and WDOP1 could significantly alleviate glucose intolerance, insulin resistance, oxidative stress injury, serum lipid metabolism disturbances, and histopathological damage in T2DM mice. In addition, we demonstrated that WDOE and WDOP1 reversed gut dysbiosis by reshaping the microbiota spectrum in T2DM mice. It should be emphasized that both Dendrobium officinale extracts afforded beneficial effects in T2DM mice comparable to metformin, despite differences in examined dosages. In conclusion, we demonstrated that Dendrobium officinale derivatives have potential as T2DM management nutraceuticals.

Structural characterization and immunoregulatory activity of polysaccharides from Dendrobium officinale leaves.

In this study, two kinds of polysaccharides from leaves of Dendrobium officinale, namely DLP-1 and DLP-2, were obtained by hot water extraction, ethanol sedimentation, and chromatographic separation using DEAE-52 cellulose and Sephadex G-100 columns. They were composed of different monosaccharides and the content of monosaccharides varied significantly while DLP-1 (Mw 1.38 × 106  Da) was mainly composed of mannose (71.69%) and glucose (22.89%), and DLP-2 (Mw 1.93 × 106  Da) was constituted by rhamnose (35.05%), arabinose (24.12%), and galactose (25.65%). A triple-helical conformation was exhibited by both of them. The scanning electron microscope image of DLP-1 showed an irregular and large lamellar shape, as well as a smooth surface and a porous interior, illustrating they had an amorphous structure. In contrast, DLP-2 revealed a rough, loose, and uneven surface consisting of large sponge-like particles. Nuclear magnetic resonance analysis showed that (1→4)-ß-D-Manp, (1→4)-ß-D-Glcp, and (1→4)-2-O-acetyl-ß-D-Manp were the main linkage types of DLP-1, whereas DLP-2 was constituted by a large amount of (1→4)-ß-D-Manp, (1→4)-ß-D-Glcp, and other residues. Besides, DLP-1 and DLP-2 stimulated the proliferation and phagocytic capacities of RAW 264.7 cells and improved the production of nitric oxide, interleukin-6, TNF-α, and IL-1ß. These results proved that both DLP-1 and DLP-2 possessed excellent immunoregulatory bioactivities and could be functional food or adjuvant drug. PRACTICAL APPLICATIONS: The leaf of Dendrobium officinale is a by-product with huge biomass. The lack of systematic research on its chemical composition and pharmacologic effect, leading to a great waste of resources. In order to maximize the value of D. officinale, this study aimed to investigate the structural characteristics and immunologic effects of two polysaccharide fractions (DLP-1 and DLP-2) from D. officinale leaves, showing that DLP-1 and DLP-2 in D. officinale leaves could be used as anti-inflammatory agents to avoid wasting.

Glabridin Liposome Ameliorating UVB-Induced Erythema and Lethery Skin by Suppressing Inflammatory Cytokine Production.

Glabridin, a compound of the flavonoid, has shown outstanding skin-whitening and anti-aging properties, but its water insolubility limits its wide application. Therefore, glabridin liposome (GL) has been developed to improve its poor bioavailability, while there are few studies to evaluate its amelioration of UVB- induced photoaging. This study is performed to investigate the amelioration of GL against UVB- induced cutaneous photoaging. The prepared GL has a spheroidal morphology with an average diameter of 200 nm. The GL shows lower cytotoxicity than glabridin, but it has a more effective role in inhibition of melanin. Moreover, the application of GL can effectively relieve UV radiation induced erythema and leathery skin, associated with the down-regulated expression of inflammatory cytokines (TNF-α, IL-6 and IL-10). Taken together, these results demonstrate that GL has potentials as topical therapeutic agents against UVB radiation induced skin damage through inhibiting inflammation.