ABSTRACT
Adult neurogenesis,a complex process by which stem cells in the hippocampal brain region proliferate and differentiate into new neurons and other resident brain cells,is known to be affected by many intrinsic and ex-trinsic factors,including diet. Neurogenesis plays a critical role in neural plasticity,brain homeostasis and mainte-nance in the central nervous system and is a crucial factor in preserving the cognitive function and repair of dam-aged brain cells affected by aging and brain disorders. Intrinsic factors such as aging,neuroinflammation,oxidative stress and brain injury, as well as lifestyle factors such as high-fat and high-sugar diets and alcohol consumption and opioid addiction,negatively affect adult neurogenesis.Conversely,many dietary components such as curcumin, resveratrol,blueberry polyphenols,polyunsaturated fatty acids (PUFAs), as well as caloric restriction, physical exercise and learning,have been shown to induce neurogenesis in adult brains. Although many of the underlying mechanisms by which nutrients and dietary factors affect adult neurogenesis have yet to be determined, nutritional approaches provide promising prospects to stimulate adult neurogenesis and combat neurodegenerative diseases and cognitive decline. In this review,we summarize the evidence supporting the role of nutritional factors in modifying adult neurogenesis and their potential to preserve cognitive function during aging.
ABSTRACT
Objective In emergency situations where simultaneous immunization by multiple vaccines are required,how to rapidly evaluate the effect of combined immunization is an urgent issue that needs to be solved.This study aimed to investigate the po-tential role and application value of the phenotypic changes of macrophages in rapid evaluation of the effect of combined Yersinia pestis and Brucella bovis vaccine immunization at early stage.Methods Y.pestis and B.bovis vaccines were injected into mice alone or in combination to establish animal models.The changes of the macrophage phenotypes(M1 or M2 polarization)and the CD8+T cell pheno-types and functions were detected in the early(4 d)and the late(14 d)stage of the immunization,respectively.The effect of the immuno-phenotype of macrophages at early stage on the function of CD8+T cells at late stage was analyzed.Results The co-immunization by Y.pestis and B.bovis vaccines led to the attenuation of the M1-polarization of macrophages at early stage,which were marked by de-creased expression of CD16/32 and increased expression of Detectin-1 on cell surface as well as decreased expression of IL-12 and in-creased expression of IL-4 inside the macrophage,in comparison with single vaccine groups,suggesting an interference between the two vaccines.Meanwhile,the activity of CD8+T cells(including the ratio of CD8+CD69+T,CD8+IFN-γ+T and CD8+GranzymeB+T cells) in combined immunization group showed similar tendency to the attenuated phenotypic M1-polarization of macrophages. Conclusion The phenotype of macrophages at the early stage of the co-immunization by Y.pestis and B.bovis vaccines showed consistency with the phenotype and function of CD8+T cells at late stage.It might give us some hint about the possibility of utilizing the phenotypic changes of macrophages to rapidly evaluate the effect of the co-immunization at early stage.