Long-term icariin treatment ameliorates cognitive deficits via CD4+ T cell-mediated immuno-inflammatory responses in APP/PS1 mice

Abstract

Tianrui Zhu,1 Feng Zhang,1 Heng Li,1 Yi He,2 Guitao Zhang,1 Nana Huang,1 Mingming Guo,3 Xiaohong Li11Department of Neurology, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, People’s Republic of China; 2Department of Neurology, The Second Affiliated Hospital of Xi’an Medical University, Xi’an, Shaanxi 710021, People’s Republic of China; 3Department of Breast Surgery, The Second Hospital of Shandong University, Jinan, Shandong 250033, People’s Republic of ChinaBackground: Alzheimer’s disease (AD) is the most common neurodegenerative disorder that also involves neuroinflammation in addition to many other features. Icariin (ICA) as one of the active ingredients of Chinese herbal medicine has the immunomodulating function. This study aimed to investigate the immunotherapeutic potential of ICA on AD.Methods: APP/PS1 mice and wild type C57BL/6 mice were subjected to orally ICA administration (60 mg/kg/d) for 8 months. Then, the ethological and biochemical experiments, such as Morris water maze assay, Aβ ELISA, blood T cell flow cytometry, and plasma and brain cytokines array, were conducted to evaluate the effects of ICA administration.Results: ICA significantly improved spatial learning and memory retention in APP/PS1 mice. Long-term application of ICA could also reduce hippocampus Aβ deposition, modulate the differentiation of CD4+ T cells, and modulate the release of inflammatory cytokines in plasma and brain tissue.Conclusion: ICA shows the neuroprotective effects via modulating the CD4+ T lymphocyte-related immuno-inflammatory responses in APP/PS1 mice and may be a promising drug against AD progression.Keywords: Alzheimer’s disease, icariin, T lymphocyte, neuroinflammation, cytokines

Keywords

• Alzheimer’s disease
• icariin
• T lymphocyte
• neuroinflammation
• cytokines