Neurons in the hippocampus of chemobrain versus non-chemotherapy brain / 中国组织工程研究

BACKGROUND:Chemotherapy drugs have been shown to penetrate the blood-brain barrier and cause neurotoxicity,further damaging nerve cells.OBEJCTIVE:To investigate the changes in the expression and morphology of hippocampal neurons in chemobrain,and to investigate the underlying mechanism of nerve regeneration in chemobrain.METHODS:The brain specimens were obtained from the six patients undergoing cancer chemotherapy and six patients without chemotherapy,and were then subdivided into two groups:＜ 60 years and ＞ 60 years groups (n=3 per group).Immunofluorescence staining with specific antibodies was used to detect the changes in the morphology and number of neurons in the hippocampus CA1,CA2 and CA3.RESULTS AND CONCLUSION:The number of neurons positive for NeuN,DCX and PV in the hippocampal CA1,CA2 and CA3 in the chemotherapy group was significantly lower than that in the non-chemotherapy group.Moreover,the neurons positive for PV were smaller,with less and shorter nervous processes.Immunofiuorescence staining findings showed that the ＜ 60 years old patients in the chemotherapy group had less neurons positive for NeuN and DCX than that in the non-chemotherapy;for ＞ 60 years old patients,there was no significant difference between two groups.These findings suggest that chemotherapy can downregulate the expression of immature neurons in the hippocampus and reduce the number of neurons in the hippocampus.Moreover,chemotherapy can change the morphology and reduce the number of PV neurons.

Gastrointestinal absorption and pharmacodynamic research of insulin-loaded poly(lactic acid) nanoparticles for oral administration / 中国药理学通报

AIM To investigate the effect of DO C(deoxycholic acid) on the absorption of INS-PLA-NP[insulin-loaded poly(lactic acid) nanoparticles] in different sites of gastrointestinal tracts. METHODS After INS-PLA-NP that contained or did not contain DOC was adminitered to different sites in gastrointestianl tracts(stomach, small intestine and colon)of normal rats, the hypoglycemic effect was observed. RESULTS The hypoglycemic effect did not exist after intragastric administration of INS-PLA-NP whether or not DOC was added. The alleviatory hypoglycemic effect was evident after intraintestinal absorption of INS-PLA-NP. After DOC was added, the absorption of INS-PLA-NP was accelerated obviously and the hypoglycemic effect was strengthened significantly. Glucose levels hardly changed after INS-PLA-NP was administered to colon. With the use of DOC, a little hypoglycemic effect appeared. CONCLUSIONS The absorption of INS-PLA-NP in small intestine was accelerated and enhanced by DOC. DOC could be used as absorption enhancer of INS-NP in the future.