| Objective The cause of ASD was complex, in recent years, with the deepening research of ASD, the pathogenesis, diagnosis and intervention therapy research of ASD has made new breakthroughs.The treatment of autism in clinical is mainly psychological intervention combined with drug treatment. However, because of the lack of drug on autism of core autism symptoms, and there are many adverse reactions and the prognosis effect is not very obvious; the training intervention approach also because of lacking of the basis of evidence-based medicine treatment, curative effect is not so valid. The sense of smell is one of the earliest and most important sense of animal development, olfactory pathway is closely related with many functional brain regions, which involved in regulating mood and behavior such as learning and memory, and the damage of olfactory pathway was associated with the occurrence of many diseases. Olfactory pathways involved in the regulation of neurotransmitters in regions such as hippocampus, amygdala, hypothalamus, pear-shaped cortex, entorhinal cortex and striatum. Previous studies have found that aromatic substances contains rich essential oil, and it via olfactory pathways has effect on the central nervous system, which can be used as a new method of therapeutic intervention or auxiliary intervention for the diseases of the nervous system. Studies have shown that the active ingredient of magnolia volatile oil has the functions on relieving rheumatism and cold, improving local blood circulation, bacteriostatic antiviral, convergencing blood vessels and so on. Whether the olfactory pathway has effect on this kind of diseases of the central nervous system? If the aromatic small molecules by the method applied to autism can lead to ideal therapeutic intervention? And what is its action mechanism?This research is to exploring the effect of magnolia volatile oil on behavior of learning and memory in in kunming mice with autism, investage the influence of the delivery system by olfactory pathway for autism intervention treatment effect and the mechanism.Part One Establish and evaluate the Autism Kunming mice ModelMethodsPregnant Kunming mice received a single intraperitoneal injection of sodium valproate 0.25ml/100g on the 12.5 day after conception, Observe and compare the body quality and the other physiological indicators of three to evaluate whether autism model preparation is success. The newborn mice were divided into three groups, model group, inhalation group, and control group, each group was 12 mice.ResultsAfter injection of VPA during pregnancy, compare the three groups of physiological indicators of newborn kunming mice, compared with the control group, the quality growth of model group was significantly slower than that of control group, and other physiological development indicators such as upper and lower incisors growth time, open testicular descent time later than the control group, with significant difference (P<0.05).Part Two The observation of neuroethology behavior in kunming mice with autismMethodsNeuroethology behavior studies include open field text, communication disorders experiment, social interaction experiment and depression behavior experiments. Open field experimental determinates the explore behavior of mice in the new environment; communication disorders experiment reflects its odor identification ability; social interaction experiment tests its communicative behavior and peer social interaction; depression behavior experiment reflects its desire to escape the desperate environment.ResultsCompared with control group, cross grid number and vertical number of model group in open field test were decreased significantly (P<0.05), the defecation grain number and the number of self modify of model group were significantly greater than that of control group, and the results have significant difference (P<0.05); in social communication disorders experiment, the smell of social smell time (P<0.05) of the two groups were significantly greater than that of nonsocial smell time, and the model group (13.57±4.04)smell the social smell time significantly less than the control group (25.87±4.64), the results have significant difference (P<0.001); in social behavior experiment, compared with the control group, the model group of following company, the number of physical contact and the regional visit time decreased significantly, and the results have significant difference (P<0.001), and self modification number is no significant difference (P>0.05); depression behavior experiment results show that the model group of accumulation fixed time in forced swimming test (FST) and the accumulation of tail suspension test (TST) fixed time (80.2±24.34) significantly greater than that of control group, the results have significant difference (P<0.05).Part Three Magnolia volatile oil via the olfactory pathway to improve the learning and memory ability in kunming mice with autismMethodsAfter the neuroethology behavior experiment, inhalation group given magnolia volatile oil for 2 weeks, then the Morris water maze was used to observe and compare the learning and memory ability. Observe the effect of magnolia volatile oil on learning memory behavior in kunming mice with autism.ResultsIn the navigation phase, the escape latency of the two group were increased with training days, the escape latency of model group was obviously longer than control group and inhalation group (P<0.05); in space exploration stage, the model group (8.12±2.66) wear platform number less than inhalation group (12.2±3.25) and normal group (14.30±3.66), the results have significant difference (P< 0.05).Part Four The observation of nerve morphology and the Influence on 5-HT and DA of magnolia volatile oil InhalationMethodsAfter absorption of magnolia volatile oil, morris water maze experiment shows that the learning memory ability of model group mice were improved significantly. To explore the mechanism of action, HE staining and immunohistochemical method were used to detect the 5-HT and DA protein expression changes in hippocampus and the amygdala and the hypothalamus area. And through the study of the image analysis of various brain regions, determine the brain the 5-HT and DA were determined the average optical density of positive reaction product.ResultsHE staining results showed that the normal group of cells was most, neat rows of structure was clear; model group cell count was least, irregular form, and structure was not clear;Suck olfactory cell groups number, the structure was clear. Immunohistochemical study results showed, the control group in various brain regions 5-HT and DA immune response were strongest, immune reaction products for brown granules, compact arrangement; model group 5-HT and DA immune response was weakest, fewer cells; inhalation group of immune reaction were medium, cell color is deeper, and more compact.Conclusions1. The olfactory pathway is closely related to diseases of the nervous system.2. Magnolia volatile oil inhalation via olfactory pathway can improve the learning and ab memory ility in kunming mice with autism, and its mechanism may be related toin e 5-HT and DA brain areas. |
