Long-term consumption of different doses of Grifola frondosa affects immunity and metabolism: correlation with intestinal mucosal microbiota and blood lipids

GYY4137, as a slow-releasing H2S donor, ameliorates sodium deoxycholate-induced chronic intestinal barrier injury and gut microbiota dysbiosis

Introduction

Numerous studies have revealed that a long-term high-fat diet can raise intestinal deoxycholate acid concentration, which can harm intestinal mucosal barrier function in several ways. This study aims to verify the protective effect of GYY4137, as a slow-releasing H2S donor, on microbiome disturbance and the chronic injury of the intestinal mucosal barrier function caused by sodium deoxycholate.

Methods

Caco-2 monolayer and mouse models were treated with a relatively high concentration of sodium deoxycholate (1.0 mM and 0.2%, respectively) for longer periods (32 h and 12 weeks, respectively) to understand the effects of GYY4137 on sodium deoxycholate-induced chronic intestinal barrier dysfunction and its fundamental mechanisms.

Results

A relatively long period of sodium deoxycholate treatment can remarkably increase the intestinal barrier permeability, alter the distribution and expression of tight junction proteins and generate the production of pro-inflammatory cytokines (TNF-α and IL-1β) in the Caco-2 monolayers and mouse models. Moreover, it can activate the MLCK-P-MLC2 pathway in the Caco-2 monolayers, which was further confirmed using RNA sequencing. The body weight, intestinal barrier histological score, and TUNEL index of sodium deoxycholate-treated mice worsened. In addition, an induced microbiome imbalance was observed in these mice. The above variations can be reversed with the administration of GYY4137.

Conclusion

This study demonstrates that GYY4137 ameliorates sodium deoxycholate-induced chronic intestinal barrier injury by restricting the MLCK-P-MLC2 pathway while elevating the expression level of tight junction proteins, anti-apoptosis and maintaining the microbiome's homeostasis.

Extracts of Grifola frondosa inhibit the MAPK signaling pathways involved in keratinocyte inflammation and ameliorate atopic dermatitis

BACKGROUND/OBJECTIVES

Grifola frondosa, commonly referred to as the maitake mushroom, has been studied extensively to explore its potential health benefits. However, its anti-inflammatory effects in skin disorders have not been sufficiently elucidated. This study aimed to elucidate the anti-inflammatory role of the ethanol extract of G. frondosa in atopic dermatitis (AD) using in vivo and in vitro models.

MATERIALS/METHODS

We investigated its impact on skin and spleen inflammatory responses in Dermatophagoides farinae extract (DFE)/1-chloro-2,4 dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in a mouse model. Additionally, we determined the immunosuppressive response and mechanism of G. frondosa by inducing atopic-like immune reactions in keratinocytes through tumor necrosis factor (TNF)-α/interferon (IFN)-γ stimulation.

RESULTS

Our study revealed that G. frondosa ameliorates clinical symptoms in an AD-like mouse model. These effects contributed to the suppression of Th1, Th2, Th17, and Th22 immune responses in the skin and spleen, leading to protection against cutaneous inflammation. Furthermore, G. frondosa inhibited the production of antibodies immunoglobulin (Ig)E and IgG2a in the serum of AD mice. Importantly, the inhibitory effect of G. frondosa on inflammatory cytokines in TNF-α/IFN-γ-stimulated AD-like keratinocytes was associated with the suppression of MAPK (Mitogen Activated Protein Kinase) pathway activation.

CONCLUSIONS

Collectively, these findings highlight the potential of G. frondosa as a novel therapeutic agent for AD treatment and prevention.