Polysaccharide of Atractylodes macrocephala Koidz (PAMK) has been well recognized as an immune enhancer that can promote lymphocyte proliferation and activate immune cells. The purpose of this study was to evaluate the effects of PAMK on humoral and cellular immune functions in immunosuppressed geese. Geese of the Control group were provided with normal feed, the PAMK group was provided with 400 mg·(kg body weight)⁻¹ PAMK, the cyclophosphamide (CTX) group was injected with 40 mg·(kg body weight)⁻¹ cyclophosphamide, while the CTX+PAMK group received the combination of PAMK and CTX. Spleen development and percentages of leukocytes in peripheral blood were examined. Principal component analysis was conducted to analyze correlations among humoral and cellular immune indicators. The results showed that PAMK alleviated the damage to the spleen, the decrease in T- and B-cell proliferation, the imbalance of leukocytes, and the disturbances of humoral and cellular immunity caused by CTX. Principal component analysis revealed that the relevance of humoral-immunity-related indicators was greater, and the CTX+PAMK group manifested the largest difference from the CTX group but was close to the Control group. In conclusion, PAMK alleviates the immunosuppression caused by CTX in geese, and the protective effect on humoral immunity is more obvious and stable.

A novel gout disease, characterized by visceral urate deposition with high-mortality, with outbreaks in goslings in China since 2016 was caused by a novel goose astrovirus (GoAstV) and resulted in serious economic loss. However, the epidemiology and variation of the GoAstV in goslings in southern China and its evolutionary history as well as the classification of the GoAstV are unclear. In the present study, systematic molecular epidemiology, and phylogenetic analyses of the GoAstV were conducted to address these issues. Our results showed that the GoAstV is widespread in goslings in southern China, and the genomes of six GoAstV strains were obtained. Two amino acid mutations (Y36H and E456D) were identified in capsid proteins in this study, which is the dominant antigen for the GoAstV. In addition, the GoAstV could be divided into two distinct clades, GoAstV-1 and GoAstV-2, and GoAstV-2 is responsible for gout outbreaks in goslings and could be classified into Avastrovirus 3 (AAstV-3), while GoAstV-1 belongs to Avastrovirus 1 (AAstV-1). Moreover, the emergence of GoAstV-2 in geese was estimated to have occurred in January 2010, approximately 12 years ago, while GoAstV-1 emerged earlier than GoAstV-2 and was estimated to have emerged in April 1985 based on Bayesian analysis. The mean evolutionary rate for the GoAstV was also calculated to be approximately 1.42 × 10⁻³ nucleotide substitutions per site per year. In conclusion, this study provides insight into the epidemiology of the GoAstV in goslings in southern China and is helpful for understanding the origin and evolutionary history as well as the classification of the GoAstV in geese.

The present study aimed to explore the mechanism by which PAMK alleviates cyclophosphamide (CTX)-induced ferroptosis in thymocytes. One-day-old goslings were divided into four groups (10 goslings/group). The CON and CTX groups were fed a basic diet. The PAMK and CTX + PAMK groups were fed the basic diet mixed with PAMK (400 mg/kg). Moreover, the CTX and CTX + PAMK groups were given a daily injection of 40 mg/kg BW of CTX (at 19, 20, and 21 days of age). On the other hand, the CON and PAMK groups were given 0.5 mL of sterilized saline into the leg muscle (at 19, 20, and 21 days of age). The goslings were fed for 28 days. The ferroptosis pathway was enriched in transcriptome sequencing. Compared to the CON group, the thymus in the CTX group underwent injury, and the mitochondria of thymocytes showed features of ferroptosis. PAMK treatment alleviated ferroptosis in thymocytes and thymus injury, and CTX-induced elevated levels of oxidative stress and iron content restored GPX4 protein expression (p < 0.05) and inhibited the CTX-induced activation of the ferroptosis pathway (p < 0.05). Conclusively, PAMK could reduce thymus injury by alleviating CTX-induced thymocyte ferroptosis in gosling to alleviate the immunosuppression caused by CTX in the organism.

Thymic degeneration and regeneration are regulated by estrogen and androgen. Recent studies have found that long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are involved in organ development. In this study, RNA sequencing (RNA-seq) results showed that ovariectomy significantly affected 333 lncRNAs, 51 miRNAs, and 144 mRNAs levels (p < 0.05 and |log2fold change| > 1), and orchiectomy significantly affected 165 lncRNAs, 165 miRNAs, and 208 mRNA levels in the thymus. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differentially expressed genes (DEGs) were closely related to cell development and immunity. Next, we constructed two lncRNA–miRNA–mRNA networks using Cytoscape based on the targeting relationship between differentially expressed miRNAs (DEMs) and DEGs and differentially expressed lncRNAs (DELs) analyzed by TargetScan and miRanda. Besides, we screened DEGs that were significantly enriched in GO and in ceRNA networks to verify their expression in thymocytes and thymic epithelial cells (TECs). In addition, we analyzed the promoter sequences of DEGs, and identified 25 causal transcription factors. Finally, we constructed transcription factor-miRNA-joint target gene networks. In conclusion, this study reveals the effects of estrogen and androgen on the expression of miRNAs, lncRNAs, and mRNAs in mice thymus, providing new insights into the regulation of thymic development by gonadal hormones and non-coding RNAs.