The polysaccharide of Atractylodes macrocephala koidz (PAMK) alleviates cyclophosphamide-mediated immunosuppression in geese, possibly through novel_mir2 targeting of CTLA4 to upregulate the TCR-NFAT pathway

Wanyan Li; Danning Xu; Bingxin Li; Nan Cao; Sixuan Guo; Qingyan Jiang; Yunbo Tian

doi:10.1039/c8ra00368h

The polysaccharide of Atractylodes macrocephala koidz (PAMK) alleviates cyclophosphamide-mediated immunosuppression in geese, possibly through novel_mir2 targeting of CTLA4 to upregulate the TCR-NFAT pathway

RSC Adv. 2018 Jul 27;8(47):26837-26848. doi: 10.1039/c8ra00368h. eCollection 2018 Jul 24.

Authors

Wanyan Li^{1

2}, Danning Xu¹, Bingxin Li¹, Nan Cao¹, Sixuan Guo¹, Qingyan Jiang², Yunbo Tian¹

Affiliations

¹ Guangdong Province Key Laboratory of Waterfowl Healthy Breeding Guangzhou 510225 P. R. China tyunbo@126.com.
² Guangdong Provincial Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University Guangzhou 510642 P. R. China.

Abstract

The polysaccharide of Atractylodes macrocephala koidz (PAMK) has been proved to have antioxidant, anti-inflammatory, antiviral, and immunity promoting effects. MicroRNAs (miRNAs) have also been shown to participate in the regulation of immune function by negatively regulating the expression of target genes. However, little is known about how PAMK alleviates the immunosuppression via the miRNA pathway in geese. The aim of this study is to evaluate the influence of PAMK on immunosuppression. Magang geese (1 day old, n = 200) were randomly divided into groups, namely, the control group (normal feeding), PAMK (fed 400 mg kg^-1 PAMK), CTX (injected 40 mg kg^-1 BW cyclophosphamide), and CTX + PAMK (40 mg kg^-1 BW cyclophosphamide + 400 mg kg^-1 PAMK) groups. Thymus development was examined by the thymus index, transmission electron microscopy and scanning electron microscopy. The T cell proliferation rate was stimulated by phytoagglutinin (PHA), and T cell activation related genes (CD28, CD96, MHC-II), and IL-2 levels in serum were detected. Differentially expressed miRNAs of geese to regulate T cell activation were found by miRNA sequencing technologies. The results showed that PAMK could alleviate thymus damage and the decrease in the T lymphocyte proliferation rate, T cell activation, and IL-2 levels that were induced by CTX. MiRNA sequencing found that the combination of PAMK and CTX significantly promoted T cell activation via upregulation of novel_mir2 (P < 0.05), which inhibited cytotoxic T lymphocyte antigen 4 (CTLA4) expressions, thereby promoting the TCR-NFAT signaling pathway. It can be concluded that PAMK, through novel_mir2 targeting of CTLA4 to upregulate TCR pathway, finally alleviated immunosuppression induced by CTX in geese.