Corrigendum to "Dendrobium huoshanense stem polysaccharide ameliorates rheumatoid arthritis in mice via inhibition of inflammatory signaling pathways" [Carbohydr. Polym. 258 (2021) 117657]

Dendrobium officinale Kimura et Migo polysaccharide ameliorated DNFB-induced atopic dermatitis in mice associated with suppressing MAPK/NF-κB/STAT3 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium officinale Kimura et Migo as a valuable Chinese medicine has been used in China for more than 2000 years. Its main active components, polysaccharide (DOP), has been reported to have various pharmacological effects, including anti-inflammatory, antioxidant and alleviating AD effects. However, the precise mechanism underlying its therapeutic effect in AD remains largely unclear.

AIM OF THE STUDY

The present study sought to assess the efficacy of DOP and elucidate its intricate mechanisms in ameliorating DNFB-induced AD.

MATERIALS AND METHODS

Mice were sensitized with DNFB and treated with DOP application for 14 days. Treatment effects were assessed using dermatitis scores, ear thickness and scratching frequency. Epidermal thickness, mast cells and CD4+ T cells infiltration were detected by using H&E, toluidine blue staining and immunofluorescence staining respectively. Serum histamine (HIS), immunoglobulin E (IgE), thymic stromal lymphopoietin (TSLP), skin SOD, MDA, GHS, CAT, inflammatory cytokines (TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-13) and chemokine (MIP-α, MDC, MCP-1) levels were quantify by ELISA and immunohistochemistry. Additionally, qPCR and Western blot analyses were performed to assess genes and proteins expression associated with MAPK/NF-κB/STAT3 signaling pathway.

RESULTS

The results indicated that DOP effectively mitigated AD-like skin lesions in mice through multiple pathways. It reduced epidermal thickness, ear thickness and scratching frequency in AD mice. Additionally, DOP mitigated inflammatory responses by decreasing the levels of inflammatory factors, as well as reducing serum levels of IgE, HIS, and TSLP. Moreover, DOP inhibited infiltration of mast cells and CD4+ T cells, suppressed the expression of skin chemokines such as MDC, MCP-1, and MIP-α, and enhanced filaggrin content in AD mice. Furthermore, DOP significantly boosted antioxidant capacity, as well as significantly reduced the expression of JAK1, STAT3, NF-κB p65, IκBα, ERK1/2, and p38 proteins and phosphorylated proteins such as p-JAK1, p-STAT3, p-NF-κB p65, p-IκBα, p-ERK1/2, and p-p38.

CONCLUSIONS

These findings suggested that DOP has significant anti-AD activity, primarily through reducing inflammatory responses, improving antioxidant capacity, repairing the skin barrier, and down-regulating key genes and proteins in MAPK/NF-κB/STAT3 signaling pathway, and that this study may provide valuable insights into the development of innovative therapies for the treatment of AD.

Extracellular polysaccharides from Sporidiobolus pararoseus alleviates rheumatoid through ameliorating gut barrier function and gut microbiota

Rheumatoid arthritis (RA) is becoming a prevalent autoimmune disease affecting people worldwide, necessitating the exploration of novel therapeutic approaches due to the associated adverse effects of conventional therapeutic drugs. Sporidiobolus pararoseus polysaccharide (SPP) has been shown to exhibit significant immune stimulation and antioxidant activities. In this study, we constructed a mouse model of type II collagen-induced arthritis (CIA) to investigate the effects and potential mechanisms of SPP intervention on RA. Results showed that SPP intervention alleviated the degree of ankle swelling, joint histopathologic changes, joint pathological score and the expression of serum-associated inflammatory mediators (such as IL-1β and IL-6). 16S rRNA sequencing results indicated that SPP intervention significantly remodeled the intestinal microbiota composition. In particular, SPP intervention significantly increased the relative abundance of beneficial bacteria (Parabacteroides, Bacteroides and Rikenellaceae_RC9_gut_group) with the potential to degrade fungal polysaccharides or produce short-chain fatty acids (SCFAs). The production of SCFAs (especially acetic acid, propionic acid and butyric acid) indeed increased significantly. These SCFAs played an important role in maintaining intestinal barrier function and regulating immune homeostasis, which helped reduce inflammatory responses and alleviate the symptoms of RA.