The Effect Of RhG-CSF On Neural Cell Apoptosis And Expression Of Bcl-2 And P53 In Diabetes Complicating Cerebral Infarction Rats

PrefaceGranuloctye colony-stimulating factor (G-CSF ) is one of the growth factors which can be used in clinic. It has been used presently in Phase I/II trials for ischemic stroke in humans. Though a lot of studies have shown that G-CSF have the capacity to provide significant neuroprotection in cerebral ischemia in vivo, there has no report whether it has the same role on the diabetes complicating cerebral infarction to date.Diabetes complicating cerebral infarction can bring patients severe neurologic impairment. Nerve cell apoptosis are the important patho-link. Inhibiting the happening of apoptosis can lessen nerve injury.Studies have showed G-CSF can pass the blood brain barrier, bind with its receptor and have an important role on the central nervous system. It is associated with many nervous system diseases and it can mobile the bone marrow stem cell to the nervous stem cell. The mechanism of action may include: anti-apoptosis, anti-inflammatory, promoting vascularization and promoting the differentiation of nerve progenitor cell and so on.We observed the effects of rhG-CSF improving neurological deficits , inhibiting nerve cell apoptosis and the expression of Bcl-2 and p53 on diabetes complicating cerebral infarction rats to investigate the neuroprotective effect mechanism of rhG-CSF to diabetes complicating cerebral infarction. Materials and method1. GroupsAll rates were divided into two groups randomly: control group, rhG-CSF group .Each group was divided into three subgroups including 6 rats of each one. Three subgroups of rhG-CSF group were received subcutaneous injection of rhG-CSF 50μg/kg·d after model preparation and control group were received subcutaneous injection of natrii chloridi.2. To establish modelsDiabetiac rats models are established with alloxan . Rats were intraperitoneally injected with alloxan 120,100mg/Kg for the continual two days. The blood-fasting sugar (BFS) were measured with glucose oxidase method after seventy-two hours of the second injection. The rats of BFS≥16.7mmol/L were as diabetic rats. Six weeks later the diabetes rats were given an anaesthesia by intraperitoneal injection with 10% chloral hydrate. Then the diabetes rats had been made MCAO models.3. rhG-CSF interventionThree rhG-CSF subgroups were received subcutaneous injection with rhG-CSF as 50μg/kg·d after model preparation and the control groups were received subcutaneous injection with Sodium Chloride of the same dose.4. Neurological severity scores5. To detect the nerve cell apoptosis with TUNEL method6. To detect the expression of Bcl-2 and p53 with immunohistochemical methodResults1. The neurological score was significantly improved in the rhG-CSF groups compared with the control group.2. Cell apoptosis was significantly decreased in the rhG-CSF group compared with the control group.3. The expression of Bcl-2 significantly was increased and that of p53 was significantly decreased compared with the control group. Diabets can complicate cerebral infarction easily .It is very difficult to cure the neurologic impairment because of its severe injury of blood vesseland and dysbolism when complicating cerebral infarction. So it is important to find an effective treat method.Apoptosis participates the form and development of nerve injury after cerebral ischemia. Apoptosis is a process of gene regulation. Bcl-2 and p53 are looked as the important genes of inhibiting and promoting apoptosis. If some drug can promote the express of Bcl-2 and inhibit the express of p53 to anti-apoptosis, it will has the significance to treat ischemic cerebrovascular disease.Granuloctye colony-stimulating factor(G-CSF) is a hematopoietic cell growth factor. It has the ability of mobilizing bone marrow stem cell including haemopoietic stem cell(HSC) and desmohemoblast stem cell (DSC) to the infarction location of ischemic cerebral infarction animal model .It can activate adult nerve stem cell, excite hyperplasy and differentiation and can excrete neurotrophic factor , diminish ischemic focus , promote neurofunctional long-term recovery. The mechanism of action may include a lot of pathway such as anti-apoptosis, anti-inflammatory, encouraging vascularization and promoting neuro ancestral cell differentiation and so on. G-CSF has a charming prospect on stroke as a new neurotrophic factor (NTF).Some researches have shown G-CSF can prevent the diabetes and also lots of studies have shown that it can lessen nerve injury of cerebral ischemia animal model. But to the diabetes complicating cerebral infarction whether it has the same role , it has not been yet report now.Our study from the point of anti-apoptosis view observed that after the intervention of rhG-CSF the neurological score significantly was lower than that of control group. It illustrated that rhG-CSF can improve nerve function. At the same time our study also showed that cell apoptosis was significantly decreased in the rhG-CSF group compared with the control group. It hinted rhG-CSF can anti-apoptosis of ischemia border area. Our study also showed the expression of Bcl-2 significantly was increased and that of p53 was significantly decreased compared with the control group in the cerebral ischemia border area after three days , seven days and fourteen days of cerebral ischemia. Accordingly at every time point apoptosis of nerve cell was decreased obviously. This point hinted anti-apoptosis role of rhG-CSF maybe come true from increasing Bcl-2 protein expression and decreasing p53 protein expression.Therefore that rhG-CSF improved neurologic impairment of diabetes complicating cerebral infarction may be concerned with increasing Bcl-2 protein expression , decreasing p53 protein expression and lessening brain tissue cell apoptosis of cerebral ischemia border area.Because our study only certified rhG-CSf had the neuroprotective effect on diabetes complicating cerebral infarction rats there had no idea which was treated best on cerebral infarction, diabetes or diabetes complicating cerebral infarction. So we decided to prove it on the next studies.At the same time , our study investigated the anti-apoptosis effect of the rhG-CSF only on the level of cell and protein ,the concrete molecule mechanism should be proved on the next studies.ConclusionsrhG-CSF can enhance the therapeutic potency possibly through inhibition of neuronal apoptosis, increasing Bcl-2 expression and decreasing p53 expression and that might be one of the therapeutic mechanisms of rhG-CSF treating diabetes complicating cerebral infarction...