Yigong Powder regulates CXCL12/CXCR4 signaling to reduce glutamate release and prevent cognitive decline in mouse model of aging / 中国中药杂志

This study aims to explore the effect of preventive administration of Yigong Powder on the learning and memory abilities of the mouse model of aging induced by D-galactose and decipher the underlying mechanism, so as to provide a basis for the application of Yigong Powder in the prevention and treatment of cognitive decline. Forty KM mice were randomized into control, model, donepezil(1.5 mg·kg~(-1)), and high-dose(7.5 g·kg~(-1)) and low-dose(3.75 g·kg~(-1)) Yigong Powder groups. The mice in other groups except the control group were injected with D-galactose(200 g·kg~(-1)) at the back of the neck for the modeling of aging. At the same time, the mice were administrated with corresponding drugs by gavage for one month. Morris water maze was used to examine the learning and memory abilities of the mice. Hematoxylin-eosin staining was employed to observe the pathological and morphological changes of the hippocampus. The immunofluorescence assay was employed to detect the expression of ionized calcium-binding adapter molecule 1(IBA1), glial fibrillary acidic protein(GFAP), chemokine C-X-C-motif ligand 12(CXCL12), chemokine C-X-C-motif receptor 4(CXCR4) in the hippocampus and observe the positional relationship between IBA1, GFAP, and CXCR4. Western blot was employed to determine the protein levels of extracellular regulated kinase(ERK), p-ERK, and tumor necrosis factor receptor 1(TNFR1). Enzyme-linked immunosorbent assay was employed to measure the levels of glutamate and tumor necrosis factor(TNF-α) in the brain tissue and the level of TNF-α in the serum and spleen. Yigong Powder significantly shortened the escape latency, increased the times crossing platforms, and prolonged the cumulative time in quadrants of the aging mice. It alleviated the nerve cell disarrangement, increased intercellular space, and cell degeneration or death in the hippocampus and reduced the pathology score of the damaged nerve. Moreover, Yigong Powder reduced the positive area of IBA1 and GFAP, reduced the levels of TNF-α in the brain tissue, serum, and spleen, and decreased spleen index. Furthermore, Yigong Powder decreased the average fluorescence intensity of CXCL12 and CXCR4, reduced CXCR4-positive astrocytes and microglia, down-regulated the protein levels of p-ERK/ERK and TNFR1, and lowered the level of glutamate in the brain tissue. This study showed that the preventive administration of Yigong Powder can ameliorate the learning and memory decline of the D-galactose-induced aging mice by regulating the immune function of the spleen and the CXCL12/CXCR4 signaling in the brain to reduce glutamate release. However, the mechanism of Yigong San in preventing and treating dementia via regulating spleen and stomach function remains to be studied.

Experimental Studies on Attenuating and Synergic effects of Modified Yigong Powder / 中药新药与临床药理

Objective To observe the effects of modified Yigong Powder (MYP) combined with chemotherapy on transplanted hepatocarcinoma of mice and to study its mechanisms. Methods Hepatocarcinoma 22 mouse model was established and then was used to observe the attenuating and synergic effects of MYP when applied together with 5-fluorouracil (5-FU). After 8 days of treatment,the tumor-inhibiting rate,activity of natural killer (NK)cells and interleukin-2 (IL-2) and small intestinal malondialdehyde (MDA) content were examined. Results MYP combined with 5-FU could increased the tumor-inhibiting rate to some extent and improve the immune function by increasing immune organ weight and increasing the activity of NK cells and IL-2. MYP combined with 5-FU could also reduce the 5-FU-induced intestinal injuries by relieving the damage of free radicals and inhibiting the lipid peroxidation and a good prognosis was expected in tumor-bearing animals treated with chemotherapy. Conclusion MYP exerts an attenuating and synergic effect when used together with 5-FU in treating tumor-bearing mice and its mechamism may be related to the improvement of immune function and reduction of intestinal injuries.