Objective The purpose of this study was to explore the expressions of EPO-R, JAK2 and STAT-5 in the human brain with refractory epilepsy and the role in neural apotosis. Methods Collecting the brain tissue of 24 patients with intractable epilepsy (as experimental group) who were hospitalized and underwent surgery in the Epilepsy Center of the First Hospital Jilin University between March 2010 to July 2011 and 6 cases of accidental or unnatural death immediately following autopsy (as control group) as required by law during the same term. Immunohistochemical was performed to observe the expression of EPO-R, JAK2 and STAT-5 in brain tissue and statistical analysis was performed. Results ① EPO-R, JAK2 and STAT-5 were expressed in both experimental and control groups. In experimental group, the positive-cell number were 41.05±2.40, 50.21±2.50 and 60.18±2.84 under light microscope (400×). While in control group, the positive-cell number were 23.00±0.49, 27.00±0.88 and 25.93±0.33. There were significant differences between the 2 groups (P<0.001). ② There were the pathologic and ultrastructural changes in the human brain with refractory epilepsy. Under the optical microscope, we can observe that the distribution of neurons was uneven and immature neurons were visible. We can see that the nuclei were vacuolar, less cytoplasm, dark staining, hyalomitome acidophilic body, and the neurons became triangular due to degeneration. The proliferation and hyperemia appeared in small vascular and glial cells. Under the transmission electron microscope we observed degeneration and necrosis of the nerve cells, nuclear karyopyknosis, nucleolis dyssymmetry and karyolemma breakage and even dissolution. The mitochondria and astrocytes were swelling. We also saw that part of the mitochondrial cristae was abnormal. Conclusion ① We found neuronal apotosis in the human brain with refractory epilepsy. ② The expression of EPO-R, JAK2 and STAT-5 in intractable epilepsy was significantly increased in neurons and glial cells compared with the control group. The high expression of EPO-R, JAK2 and STAT-5 is unrelated with course and frequency of epileptic seizures. ③ The pathway of EPO-R/JAK2/STAT-5 may be involved in the pathophysiological processes of neural protective effect of endogenous EPO against brain injury induced by epileptic seizures.
ObjectiveTo study the effects of sea cucumber polysaccharide (SCPS) on the proliferation and apoptosis of hepatocellular carcinoma (HCC) cells, and to explore its effect on JAK2/STAT3/survivin pathway. MethodsThe human HCC cell lines HepG2 were placed into 24-well plates after culturing to the logarithmic phase, then dealed with different concentrations (0, 50, 100, 200 μg/mL) of SCPS. The MTT assay was used to detect the effects of different concentrations of SCPS on cell proliferation at 12 h, 24 h, and 36 h. The effect of SCPS on cell apoptosis was analyzed by flow cytometry. The mRNA and protein expression levels of JAK2, STAT3, and survivin were detected by real-time quantitative PCR (qRT-PCR) and Western blot at 36 h after treatment with SCPS, respectively. Then, the human HepG2 cells treated with different concentrations (0, 50, 100, 200 μg/mL) of SCPS were subcutaneously xenografted into nude mice to observe the effect of SCPS on the growth of tumor tissues in nude mice. At the same time, the expressions of phosphorylated JAK2, STAT3, and survivin proteins in tumor tissues were detected by immunohistochemical method. ResultsAfter treatment with different concentrations of SCPS, the proliferation inhibition rate of HepG2 cells increased over time and increased SCPS concentrations (P<0.05). After 36 h cultivation time, the apoptosis rate of cells treated with different concentrations of SCPS was statistically significant (F=117.110, P<0.001) and increased with the increase of SCPS concentrations (P<0.05). The protein expression levels of JAK2, STAT3, survival and their phosphorylated proteins decreased gradually with the increase of SCPS concentrations (P<0.05), but there was no significant difference in the mRNA expression level (P>0.05). With the increase of SCPS concentration, the tumor volume of nude mice gradually reduced (P<0.05). At the same time, the results of immunohistochemical detection showed that the positive expression rates of phosphorylated JAK2, STAT3, and survivin proteins in tumor tissues decreased with the increase of SCPS concentrations (P<0.05). ConclusionFrom preliminary results of this study, SCPS could inhibit the proliferation of HCC cells and promote their apoptosis, which might be achieved by regulating the phosphorylated expressions of JAK2, STAT3, and survivin in the JAK2/STAT3/survivin pathway.