Impact of Terminalia chebula Retz polysaccharide and Rubia cordifolia L. processed Terminalia chebula Retz polysaccharides on cyclophosphamide-induced immunosuppression in Chinese yellow quail

Jing Wang^1*Tiejin Tong¹Wu Qiang^1*min he²

• ¹Yibin Vocational and Technical College, Yibin, China
• ²Sichuan Agricultural University, chengdu, China

Immunosuppression in poultry production poses significant challenges, especially in high-value species like the Chinese yellow quail (Coturnix japonica), where weakened immunity leads to increased disease susceptibility and economic losses. Plant-derived polysaccharides, such as those from Terminalia chebula Retz (TC) and Rubia cordifolia L. processed Terminalia chebula Retz polysaccharide (RTCP), offer promising alternatives due to their ability to enhance host defense mechanisms without adverse effects. This study evaluated RTCP's potential to alleviate cyclophosphamide (CTX)-induced immunosuppression in Chinese yellow quails, focusing on spleen indices, histological structure, cytokine profiles, antibody titers, GATA-3/T-bet mRNA expression, and transcriptional networks. One hundred and twenty healthy 21-day-old quails were randomly allocated into six groups (20 birds per group), including a blank control group (saline) and a model group (saline + CTX). and four RTCP-treated groups (0.25, 0.5, 0.75, 1 g/kg + CTX). CTX (80 mg/kg) was administered intramuscularly to all groups except the blank control on days 4-7. Our results showed that spleen weight, organ index, cytokine levels, and antibody titers (P<0.05) were significantly reduced by CTX. Compared to the model group (P<0.05), treatment with 0.5 g/kg RTCP restored the spleen indices and morphology, increased the production of cytokine and immunoglobulin, and upregulated complement components such as C3 and C5 and acute-phase proteins, which enhanced cellular T-cell and B-cell activation. The Th1/Th2 balance was also restored RTCP via normalizing the T-bet/GATA-3 ratio, indicating immune homeostasis restoration. Altogether, our study suggests RTCP acts as a promising immunomodulatory agent of counteracting immunosuppression via multiple immune pathways. Further investigations are needed on its dose optimization and gut microbiota interactions to maximize the therapeutic potential.