The fruit of Ziziphus jujuba Mill., known as jujube or Chinese date, is commonly consumed as a health supplement or herbal medicine worldwide. To study the beneficial role of jujube in regulating immune response, we investigated its roles on the expressions of pro-inflammatory cytokines in cultured macrophages. Application of chemically standardized jujube water extract for 24 h stimulated the transcriptional expression of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in cultured RAW 264.7 macrophages. In contrast, the pretreatment with jujube water extract suppressed the expression of IL-1β and IL-6, but not for TNF-α in lipopolysaccharide (LPS)-stimulated macrophages. The IL-1β and IL-6 cytokines in LPS-induced macrophages were suppressed by jujube water extract in both mRNA and protein levels. In parallel, the inhibition of jujube water extract on the transcriptional activity of nuclear factor-kappa B was revealed in LPS-induced macrophages. These results verified the bidirectional immune-modulatory roles of jujube by regulating the expressions of pro-inflammatory cytokines in macrophages.

Kai-xin-san (KXS), a Chinese herbal decoction prescribed by Sun Simiao in Beiji Qianjin Yaofang about 1400 years ago, contains Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria. In China, KXS has been used to treat stress-related psychiatric diseases with the symptoms of depression and forgetfulness. Although animal study has supported the antidepression function of KXS, the mechanism in cellular level is still unknown. Here, a chemically standardized water extract of KXS was applied onto cultured astrocytes in exploring the action mechanisms of KXS treatment, which significantly stimulated the expression and secretion of neurotrophic factors, including NGF, BDNF, and GDNF, in a dose-dependent manner: the stimulation was both in mRNA and protein levels. In addition, the water extracts of four individual herbs did not significantly stimulate the expression of neurotrophic factors, which could explain the optimized effect of KXS in a herbal decoction. The KXS-induced expression of neurotrophic factors did not depend on signaling mediated by estrogen receptor or protein kinase. The results suggested that the antidepressant-like action of KXS might be mediated by an increase of expression of neurotrophic factors in astrocytes, which fully supported the clinical usage of this decoction.

quinine oxidoreductase 1, glutamate-cysteine ligase catalytic subunit, glutamate-cysteine ligase modifier subunit and glutathione S-transferase, in a concentration-dependent manner. These results proposed the benefits of jujube in regulating expressions of neurotrophic factors and anti-oxidant enzymes in cultured astrocytes.