Screening Of Traditional Chinese Medicine (TCM) Prescriptions Against Alzheimer's Disease Using Luminex Technology

Background:Alzheimer's disease (AD)-senile dementia is recognized as one of the major risk diseases to the human health and become the fourth largest threat to the health of the elderly only after heart disease, cancer and stroke in China. Because of pathological complexity of AD, many countries in the world are searching for effective treatment for AD. Although the large amounts of human and material resources have been used, the outcome is very limited. As a natural and well practice medicine, the Chinese herbs, espacially the prescriptions hold a big advantage and potential in the treatment of the senile diseases. Therefore, it will be significant important to elucidate pharmacological mechanism of TCM prescription, screen and develop new TCM prescriptions to delay disease progress and improve life quality of AD patients.Objective:This study will use luminex technology to detect cytokines secreted by dementia animal model treated with different TCM prescriptions and record capacity changes of learning and memory of dementia animals in order to find biomarkers for ADand screen effective prescriptions against AD. The study will be basis for the establishment of AD research platform based on luminex technology, exploring new ways for screening prescriptions for prevention and treatment of ADo It is expected to screen 1-2 kinds of effective prescription for dementia animal model. Institute of Older Encephalopathy Research, First affiliated Hospital, Tianjin University of TCM. The 7-month-old SAM-prone/8 (SAMP8) mice were randomly divided into dementia group and groups treated with NaoFuKang, LiuWeiDiHuangTang, SiJunZiTang, GuipiTang and DangGuiShaoYaoSan priscription, respectively. There are 14 mice in each group and 15 SAM-resistant/1 (SAMRI) was used as the normal control group. Mice were treated wit drugs for 4 weeks and tested for the Morris water maze for six days and then sampled bilateral hippocampus and cortex by beheading, 10 cytokines including GM-CSF,IFNγ,TNFα,IL-1β,IL-2, IL-4,IL-5,IL-6,IL-10 and IL-12 in brain tissue were detected by Luminex technology and data were analyzed by using SPSS software and presented as x±s.Results:1. Compare with the normal control group, the escape latency time and swimming speed of SAM dementia group were significantly increased (P＜0.05) and decreased (P＜0.05), respectively. Compared with model group, the escape latency time of SiJunZiTang group, LiuweidihuangTang group, GuipiTang Group was decreased significantly (P＜0.05, P＜0.01) and the swimming distance of SiJunZiTang group was decreased significantly (P＜0.05).2. Compare with the normal control group, except for the downward trend of IL-6 and IL-10, The remaining eight cytokines in SAMP8 mouse cortex homogenate all rose, but only the GM-CSF was significantly higher than that in the normal control group (P＜0. 05). Compare with the normal control group all 10 cytokines in SAMP8 mouse hippocampal homogenate show a decreased trend. Except TNFαand IL-5, the concentrations of remaining eight kinds of cytokines were significantly lower than the control group (P＜0.05, P＜0.01).3. The GM-CSF level in the groups of LiuWeiDiHuangTang, DangGuiShaoYaoSan and Naofukang was similar to that in the normal control group (P＞0. 05), but GM-CSF concentration in the groups treated with SiJunZiTang and GuipiTang and model group was significantly higher than the normal control group (P＜0.05), demonstrating that the former three prescriptions may inhibit to a certain extent GM-CSF production in the cortex of SAMP8 mice. Based on the changes of concentrations of i0 cytokines in the hippocampal homogenate of SAMP8 mouse treated with different prescriptions, we found that NaoFuKang prescription, a positive control, could increase the IFNγ, IL-4 and IL-12 levels in the hippocampus of mice (P＜0.05, P＜0.01), the DangGuiShaoYaoSan prescription could increase the IL-4 and IFN levels in mouse hippocampus and the SiJunZiTang prescription could raise the IFNγlevels in mouse hippocampus (P＜0.05). The prescription LiuWeiDiHuangTang could increase cytokine concentrations of GM-CSF, IFN-γ, TNFα, IL-1β, IL-2, IL-4, IL-5, IL-6 and IL-10 (P＜0.05, P＜0.01) and restore them to the normal levels.Conclusion:1. By the testing of the Morris water maze we found that the learning and memory ability of 9-month-old SAMP8 mice decreased significantly compare with the same age normal SAMRI mice, indicating that the SAMP8 mice was the ideal animal model. The prescriptions of LiuWeiDiHuangTang, SiJunZiTang and GuiPiToup could improve the learning and memory capacity of SAMP8 mice significantly.2. Some cytokine expression in 9-month-old mice brain tissue changed abnormally including the increasement of GM-CSF in cortex and decreasement of 8 cytokines in the hippocampus. Changes in expression of proinflammatory cytokines in the brain (especially in hippocampus) may be involved in the age-related neural dysfunction and/or learning deficiency in SAMP8.3. The prescriptions of LiuWeiDiHuangTang, DangGuiShaoYaoSan and SiJunZiTang have both positive and negative effects on the immune reaction of SAMP8 mice to a certain extent and LiuWeiDiHuangTang prescription had the best effect. The regulation function of LiuWeiDiHuangTang, SiJunZiTang and Naofukang for SAM dementia mice's abnormal immune state was related to improving their cognitive dysfunction.4. In conclusion, for younger 10 months SAMP8 mice GM-CSF is recommended as a main cytokine marker in brain tissue and a candidate indicator for establishment of Luminex technology platform for AD. LiuWeiDiHuangTang prescription could be chosen as the effective prescription for the treatment and prevention of AD to do further study.