ABSTRACT
Aim To investigate the effect of extracellular vesicles secreted by adipose tissue of mice on hippocampal neurons and cognitive behavior of mice with a high-fat diet.Methods Twenty C57BL/6J male mice were randomly divided into normal diet(ND)group(n=10)and high-fat diet(HFD)group(n=10), fed for 28 weeks.The weight of mice was recorded weekly.The level of fasting blood glucose, insulin and the insulin resistance index(HOMA-IR)of mice were tested at week 27.At week 28, the learning and memory abilities of mice were assessed by the Morris water maze.The morphological differences in adipose tissue were observed by HE staining, and the extracellular vesicles secreted from adipose tissue were quantified by TEM and NTA.Extracellular vesicles derived from adipose tissue labeled with PKH 67 were injected into normal mice via the tail vein, and after 30 h, the uptake of extracellular vesicles was detected in the hippocampal slice.The primary hippocampal neurons were treated with extracellular vesicles with the same amount of protein, and the effects of them on neuronal morphology and cell viability were observed.Results Compared with ND group, mice in HFD group were significantly heavier, with hyperglycemia, hyperinsulinemia and higher insulin resistance index.In the Morris water maze test, the HFD group showed a longer escape latency and less swimming time in the target zone.The volume of adipocytes and the amount of extracellular vesicles secreted from them significantly increased in HFD group.Extracellular vesicles secreted by adipose tissue could be internalized by both the primary hippocampal neurons and the hippocampal neurons in the normal mice.Compared with ND group, extracellular vesicles secreted by adipose tissue of the HFD group significantly reduced the length of primary hippocampal neuronal dendrites, the number of primary and secondary dendrites, and the cell viability of neuron cells.Conclusion Long-term high-fat diet could damage the hippocampal neurons by affecting the extracellular vesicles derived from adipose tissue.
ABSTRACT
RNA interference induced by small interfering (siR¬NA) has shown great potential in disease treatment.However, due to the poor stability of siRNA and lack of targeting, it is still challenging to deliver siRNA to target tissues/cells and induce gene silencing.Aptamer is a kind of oligonucleotide sequence that can specifically recognize the target.Covalently binding aptamers with siRNA or linking with other siRNA carriers can guide siRNA into target tissues/cells.In this review we summa¬ rize the research progress in the design strategy and application of aptamer-based targeted deliver)' of siRNA in the treatment of diseases in recent years, and discuss the challenges and pros-pects of aptamer-mediated siRNA deliver>r in clinical transforma¬tion.
ABSTRACT
Liver failure is the end stage of hepatopathy with unfavorable prognosis. In two patients with liver failure, viable primary human hepatocytes, obtained from resected liver tissue of patients with hepatolithiasis, were transplanted into the spleen by interventional therapy through femoral arterial cannula. After transplantation, the patients' clinical symptoms and liver function were significantly improved. However, their bilirubin increased within six days following transplantation. One suffered from hepatic coma and give up treatment and the other patient died fourteen days after transplantation. It is technically safe to treat liver failure by intrasplenic transplantation of adult hepatocytes and the clinical efficacy has been confirmed. How to make transplanted hepatic cells proliferate and functionally survive is the key point to maintain continuous improvement of the recipient's hepatic function.