ABSTRACT
Objective:To investigate the effects of human umbilical cord mesenchymal stem cells exosomes (hucMSC-Exo) on depression-like behavior and polarization dynamic transition of hippocampal microglia in chronic unpredictable mild stress(CUMS) mice.Methods:The hucMSC was isolated, cultured, and the 5th generation hucMSC-Exo was extracted by ultracentrifugation and identified.Biological markers of CD9 and CD63 of hucMSC-Exo were detected by Western blot.A total of 12 SPF grade male C57BL/6J mice were randomly selected to establish depression model by CUMS method at the same time, and relevant behavioral experiments, including opening field test (OFT) and forced swimming test (FST) were used to detect changes of depression-like behavior in CUMS mice. After modeling, 12 mice were randomly divided into two groups, with 6 mice in each group. One group of mice was the exosome treatment group (CUMS+ Exo group) after stereotactic brain injection of hucMSC-Exo in the hippocampus, and the other group was the CUMS group. The expression of inflammatory signals in the hippocampus of mice in both groups were detected by micro PET/CT scanning technique. The proportion of M2-type microglia and M1-type microglia in the hippocampus of mice was detected by tissue immunofluorescence. β3-tubulin immunofluorescence staining was used to detect the length changes of neuronal axons in the depressed cell model constructed with corticosterone (CORT). EdU staining was used to detect neuronal proliferation. TUNEL staining was used to observe the apoptosis of neurons in the hippocampus of mice.Statistical analysis was conducted by GraphPad 8.0 software, and t-test was used for inter group comparison. Results:Under the electron microscope, hucMSC-Exo showed typical " double-layer cup-like" small vesicle-like changes and the particle diameter was about 100 nm.Western blot confirmed the expression of lconic proteins of CD9 and CD63. In the micro PET/CT scans, the uptake of [18F]DPA-714 in the CUMS+ Exo group was lower than that of the CUMS group, and the difference was statistically significant ((0.91±0.02)g/mL, (0.81±0.05)g/mL, t=4.54, P=0.001 1). In the opening field test, the percentage of central path length ((3.40±0.44)%, (5.17±0.90)%, t=4.33, P=0.001 5) and the time spent on the central path ((7.04±0.60)s, (10.22±1.41)s, t=6.02, P=0.000 1) in CUMS+ Exo group were higher than those in CUMS group, while the total distances of the two groups were not statistically significant ( t=0.48, P>0.05). In the forced swimming test, the immobility time in the CUMS+ Exo group was less than that in the CUMS group ((152.33±7.28) s, (133.50±4.32) s, t=5.45, P=0.000 3). In tissue immunofluorescence experiments, compared with the CUMS group, the proportion of M2-type microglia of hippocampus in the CUMS+ Exo group((0.33±0.04), (0.59±0.12), t=5.11, P=0.000 5)increased and the proportion of M1-type microglia ((0.56±0.06), (0.41±0.03), t=5.15, P=0.000 4) decreased in the CUMS+ Exo group. β3-tubulin-labeled immunofluorescence results showed an increase of neuronal axon length in the CORT+ Exo group compared with that in the CORT group((3.99±0.99) μm, (6.76±1.11) μm, t=6.10, P=0.000 1). The results of cell proliferation test showed an increase of proliferation rate in the CORT+ Exo group compared with that in the CORT group((0.74±0.07), (0.64±0.03), t=3.32, P=0.001 8). In the TUNEL staining experiment, the apoptosis rate of neurons in the hippocampal region of mice in the CUMS+ Exo group was lower than that of CUMS group ((0.24±0.04), (0.39±0.04), t=6.11, P=0.000 1). Conclusion:hucMSC-Exo can promote the conversion of M1 polarized microglia to M2 type microglia to alleviate depression-like behavior and reduce neuronal apoptosis in CUMS mice.
ABSTRACT
Objective:To study the effect of Sanjie Xiaoliu Recipe on transplanted tumors in breast cancer mice through in vivo experiments, in order to explore the efficacy and mechanism of Sanjie Xiaoliu Recipe on breast cancer patients. Methods:45 BaL B/c female mice were selected to establish the transplanted tumor model of breast cancer. All the transplanted tumor models of breast cancer mice were randomly divided into five groups: the control group (intragastric administration of normal saline), the low, medium and high dose group of Sanjie Xiaoliu Recipe (intragastric administration of different doses of Sanjie Xiaoliu Decoction), and the paclitaxel group (intraperitoneal injection of paclitaxel). After 24 days of continuous administration, the diet and activities of mice were observed; the body weight, weight and volume changes of transplanted tumor mice were recorded, and the tumor inhibition rate was calculated. Western blot was used to detect the expression of epithelial mesenchymal transformation related proteins (E-cadherin, N-cadherin, Vimentin) in the transplanted tumor tissues of mice in each group.Results:(1) The food intake and activity status of mice treated with Sanjie Xiaoliu Recipe were less affected by the transplanted tumor of breast cancer. (2) The volume and weight of transplanted tumor in the treat groups were smaller than those in the control group (all P<0.01), and the volume of transplanted tumor in the middle dose group of Sanjie Xiaoliu Recipe was smaller than that in the low dose group ( P<0.05). The tumor inhibition rates among the treatment groups were: Sanjie Xiaoliu Recipe medium dose group 52.4%, paclitaxel group 40.3%, Sanjie Xiaoliu Recipe low dose group 39.5%, Sanjie Xiaoliu Recipe high dose group 34.1%. (3) The results of Western blot showed that the expression level of E-cadherin in the transplanted tumor tissue of the treat groups was higher than that in the control group, and the expression levels of N-cadherin and Vimentin were lower than that in the control group, with statistically significant difference (all P<0.05). Conclusions:The Sanjie Xiaoliu Recipe can improve the weakness and reduced consumption of breast cancer mice, which can inhibit the tumor mass growth in mice to a certain extent. Its mechanism may be that Sanjie Xiaoliu Recipe can inhibit the epithelial mesenchymal transformation of breast cancer and the invasion and metastasis of breast cancer.