Short-chain fatty acids ameliorate allergic airway inflammation via sequential induction of PMN-MDSCs and Treg cells.

Background: Reinforcement of the immune-regulatory pathway is a feasible strategy for prevention and therapy of allergic asthma. The short-chain fatty acids (SCFAs) acetate, propionate, and butyrate are pleiotropic microbial fermentation products known to induce regulatory T (Treg) cells and exert an immune-regulatory effect. The cellular mechanism underlying SCFA immune regulation in asthma is not fully understood. Objective: We investigated the role of myeloid-derived suppressor cells (MDSCs) and Treg cells, the immune-regulatory cells of innate and adaptive origin, respectively, in SCFA-elicited protection against allergic airway inflammation. Methods: BALB/c mice were given SCFA-containing drinking water before being rendered asthmatic in response to ovalbumen. When indicated, mice were given a GR1-depleting antibody to investigate the function of MDSCs in allergic inflammation of the airways. MDSCs were sorted to examine their immunosuppressive function and interaction with T cells. Results: The mice receiving SCFAs developed less severe asthma that was accompanied by expansion of PMN-MDSCs and Treg cells. Mice depleted of PMN-MDSCs exhibited aggravated asthma, and the protective effect of SCFAs was abrogated after PMN-MDSC depletion. SCFAs were able to directly induce T-cell differentiation toward Treg cells. Additionally, we found that PMN-MDSCs enhanced Treg cell expansion in a cell contact-dependent manner. Whilst membrane-bound TGF-ß has been shown to induce Treg cell differentiation, we found that MDSCs upregulated surface expression of TGF-ß after coculture with T-cells and that MDSC-induced Treg cell differentiation was partially inhibited by TGF-ß blockage. Conclusions: Although previous studies revealed Treg cells as the effector mechanism of SCFA immune regulation, we found that SCFAs ameliorate allergic airway inflammation by relaying immune regulation, with sequential induction of PMN-MDSCs and Treg cells.

[Acupoint selection rules in treating gastroesophageal reflux disease with acupuncture in China based on data mining].

OBJECTIVE: To analyze the rules of acupoint selection in the treatment of gastroesophageal reflux disease in China using data mining technology. METHODS: The published literature of treating gastroesophageal reflux disease with acupuncture was retrieved from electronic databases from January 1, 1983 to December 1, 2019, including SinoMed, CNKI, Wanfang and VIP database. Acupuncture prescription database was established, and the rules of acupoint selection were explored by statistical software SPSS 20.0 and SPSS Modeler 18.0. RESULTS: A total of 92 articles were included into this analysis, involving 92 acupuncture prescriptions, 76 acupoints. The total frequency of using these acupoints reached 549 times. Zhongwan (CV 12) was the most frequently used acupoint; the often selected meridians were conception vessel, stomach meridian, governor vessel, bladder meridian; the acupoints located at the abdomen, lower limbs and back were commonly selected; crossing points in the specific acupoints were commonly selected; the most frequently used group was Zusanli (ST 36)-Zhongwan (CV 12) and Neiguan (PC 6). CONCLUSION: Treating gastroesophageal reflux disease by acupuncture in China is dominated by shu-mu point combination, supplemented by mu-he point combination; yin meridians are emphasized as much as yang meridians; using specific acupoints is advocated, especially the crossing points.