Experimental Study Of Gel/SA/CMCS Hydrogel Loaded ADSCs Derived Exosomes In The Treatment Of Cavernous Nerve Injury ED

Objective: To explore the therapeutic effect of exosomes derived from adipose derived stem cells combined with Gel/SA/CMCS hydrogel biomaterials on erectile dysfunction induced by nerve injury.Methods: After purchasing SD rats for about 8 weeks,adipocytes were obtained from the groin,and the primary cells were obtained by centrifugation after EDTA treatment,and then cultured in the incubator and transferred to the third generation.The surface antigens(CD29,CD90,CD34)were detected by flow cytometry,and a large number of cells were extracted and cultured.The cells were washed with PBS for three times,and then injected into serum-free DMEM culture medium to stand for 24 hours.The supernatant was extracted by ultracentrifugation.The extracted exosomes were observed by particle size,electron microscopy,and WB detection.Subsequently,gelatin carboxymethyl chitosan sodium alginate hydrogel was prepared.In the previous research of our research group,the biocompatibility of gelatin has been verified.Thirty 8-week-old SD male rats were selected and divided into three groups,10 in each group,which were divided into sham operation group,blank control group and experimental group.The blank control group did not do any treatment after finding the cavernous nerve on the dorsal side of the prostate,and immediately sutured the knife edge.The sham operation group found the cavernous nerve from the stellate ganglion on the dorsal side of the prostate,and then carried out clamp injury,and then sutured the knife edge.In the experimental group,gelatin biomaterials loaded with exocrine body were injected into the injured site immediately after nerve injury,and the histological function was tested after 4 weeks.Results: Adipose derived stem cells expressed cell surface specific antibodies CD29(98.92%),CD90(98.06%),and did not express CD34(3.06%).Under transmission electron microscope,the exocrine body extracted is a typical "cup and plate" shape,with complete morphology and uniform size.The average particle size of exocrine body is about 89.61 nm,and 30-150 nm accounts for 92.97% of the total particle number.Under the electron microscope of Gel/SA/CMCS hydrogel containing ADSCs-Exos,exosomes were found in the pores of the hydrogel,and immunofluorescence showed that exosomes and hydrogels coexisted in large quantities.The n NOS of SD rats in the sham operation group decreased,the vascular smooth muscle fibrosis was serious,the vascular lumen was occluded,and the collagen content was increased.The above indexes of SD rats in the experimental group were significantly improved.Conclusion: Gel/SA/CMCS hydrogel containing ADSCs-Exos can effectively promote neurotransmitter regeneration,inhibit fibrosis after nerve injury,and promote the recovery of erectile function.