Effects Of Saikosaponin A On Cerebrospinal Fluid Cytokines Expression Of Epileptic Rats Induced By Pentylenetetrazol

Objective and significanceEpilepsy is a common chronic disease in nervous system, which is characterized by transient disorder of cerebral function and caused by suddenly and recurrently seizure of neuron in brain. There are about 9 million epileptic patients in our country, among which about 6 million epileptic patients attacked every year. These patients and their families suffer great mental stress in their social lives. So, it cannot be ignored that there are a lot of medical, domestic and social problems caused by epilepsy.So far, the mechanism of epilepsy has not been fully uncovered. Nevertheless, many experts of epilepsy have generally accepted that there are two important characters of epilepsy: the increase of neuronal excitability and the firing of highly synchronization. The functionality of astrocytes has been thought to become stronger and stronger. It is proved that besides the ch.anges of neuron during the process of epilepsy, the astrocytes also have some important abnormality of structure and function, which can affect the function of neuron. Furthermore, the cytokines may have some important effect in the progress of the activation of astrocytes. It is discovered that the expression of cytokines increased in the epileptic patients and rats model. And it is also discovered that interleukins(IL-1β,IL-6), tumor necrosis factor(TNF-α), epidermal growth factor(EGF), basic fibroblast growth factor(bFGF), and so on, have participated in the activation of astrocytes and have some effects on the activity and cell cycle of astrocytes and on the progress of nerve stem cell becoming astrocytes.At present, the main method of controlling epilepsy is to use chemicals. However the mainly used anti-epileptic drugs (AEDs) can only control the seizure of about 70 to 80 percent of epileptic drugs while the safety of the AEDs is not satisfactory because of the side effects accompanied with long term administration, such as distractibility, insomnia, dizziness and etc. So the new anti-epileptic drug should be used or the old anti- epileptic drugs should be used in a proper way in order to increase the curative effects and decrease the side effects.Bupleurum chinense is a widely used Chinese herb, which contain some pharmaco-ingredients such as saikosaponins (SS), aetheroleas, organic acids, sterins, flavonoids, polyose etc. And saikosaponins can be divided into some monomer such as saikosaponin A (SSa), saikosaponin b2, saikosaponin c, saikosaponin d and so on. Professor Chen Bao-tian is one of the famous veteran doctors of TCM in our department. He has proposed the theory that epileptic patients should be treated from liver (of the TCM definition), then prescribed "Chai Hu Shu Gan (CHSG) Soup" to treat epileptic patients and resulted in significant curative effect. We have found in our early research that "CHSG Soup", Bupleurum chinense and SS have anti-epileptic effects and SSa is the main active component. In order to investigate the anti-epileptic effect of SSa and to see if the anti-epileptic effect of SSa is obtained by the mechanism of cytokines, the effects of Saikosaponin A on Cerebrospinal Fluid Cytokines Expression are studied on the Epileptic Rats induced by Pentylenetetrazol".Method and content1. Effect of saikosaponin A on the etiology of PTZ induced epileptic rats Used the widely received PTZ induced epileptic rats as animal model, the experimental animals are divided into three groups: model group, SSa group and VPA group. The acute epileptic rat model were made by intraperitoneal injecting 60mg/kg PTZ, the effect of SSa and VPA were observed on the incubation period of seizure and the rate oftetanic convulsion of PTZ induced epileptic rats.2. Effect of saikosaponin A on cerebrospinal fluid cytokines expression of PTZ induced epileptic rats96 health grown-up rats were randomly divided into four groups: normal control group (group A, 6 rats), model group (group B, 30 rats), SSa group (group SSa, 30 rats), VPA group (group D, 30 rats). The normal control group was induced by intraperitoneal injecting isotonic sodium chloride solution, while the other groups were induced by intraperitoneal injecting 60mg/kg PTZ and treated by different factors as above. The group B, group C and group D were then divided into five groups, gathered the cerebrospinal fluid of the rats after the rats was induced 0 hours, 2 hours, 4 hours, 8 hours and 12 hours, then detected the cytokine IL-1β, cytokine IL-6 and cytokine TNF-α.Result1. Effect of saikosaponin A on the etiology of PTZ induced epileptic rats Compared with model group, SSa group and VPA group could prolong the incubation period of clonic cramp (P＜0.05) and could prolong the incubation period of tetanic convulsion (P＜0.05). It. is suggested that SSa and VPA could prolong the incubation period of seizure of PTZ induced epileptic rats.The rates of tetanic convulsion of PTZ induced epileptic rats in the three groups were significantly different. The rate of tetanic convulsion of model group was 100%, while the rate of SSa group was 80% and of VPA group was 90%. It is evidenced that SSa and VPA could reduce the rate oftetanic convulsion of PTZ induced epileptic rats.2. Effect of saikosaponin A on cerebrospinal fluid cytokines of PTZ induced epileptic rats2.1 Effect of saikosaponin A on cerebrospinal fluid cytokine IL-1βof PTZ induced epileptic ratsWithin the first 12 hours, the expression of IL-1βin cerebrospinal fluid of epileptic rats induced by PTZ was changed in a dynamic state: increased at first, then went down to a lower level than normal and slowly raised to normal finally. In this process, SSa and VPA could inhibit the changes of the expression of IL-1βin cerebrospinal fluid of epileptic rats.2.2 Effect of saikosaponin A on cerebrospinal fluid cytokine IL-6 of PTZ induced epileptic ratsAfter induced by PTZ, the expression of IL-6 in cerebrospinal fluid of epileptic rats decreased at first, increased at 4h and then kept a high level of expression. SSa almost had no effect when the expression of IL-6 decreased at first but could restrain this tendency of its increasing. However VPA could always had the tendency of heightening, and keeping the expression of IL-6 within the experimental period.2.3 Effect of saikosaponin A on cerebrospinal fluid cytokine TNF-αof PTZ induced epileptic ratsAfter induced by PTZ, the expression of TNF-αin cerebrospinal fluid was increased rapidly, and went down to a lower level within 8 hours, and then slowly recovered back to normal. SSa and VPA could inhibit the rapidly increasing of TNF-αafter induced by PTZ.Conclusion1. We investigated the anti-epileptic effect of SSa using the epileptic rat model and discovered that SSa could either prolong the incubation period of clonic and tonic convulsion or decrease the rate of tonic convulsion. The result evidenced the anti-epileptic effect of SSa.2. The expression of cytokines (IL-1β,IL-6,TNF-α) changed in dynamic state in epileptic rats. The expression of IL-1βand TNF-αraised rapidly after induced by PTZ and decreased to normal then. While the expression of IL-6 decreased first and raised after. SSa and VPA have different effect on IL-6. VPA could increase IL-6 in 2h and keep it in a steady level, while SSa could inhibit the raising of IL-6 after treated by PTZ. And both SSa and VPA could inhibit the raising of IL-1βand TNF-αafter treated by PTZ.