Research On The Efficacy And Mechanism Of Microalgal-derived Active Peptides To Promote The Proliferation Of Hematopoietic Cells

Recently,the incidence and death rates of various blood diseases have shown an upward trend.At present,hematopoietic cell transplantation methods are used in clinical to treat a variety of blood diseases,but the number of hematopoietic cells in a single bone marrow and cord blood is limited,so it is difficult to meet the current clinical needs.Moreover,most of the drugs used to treat blood diseases have certain side effects.Therefore,this research selected the microalgal-derived active peptides HP-6 with high-security and non-toxic side effects to study the efficacy and mechanism of hematopoietic cells;at the same time,study the non-clinical pharmacokinetics of HP-6.Firstly,select healthy Wistar rats,then using the rat bone marrow lymphocyte separation solution isolated the hematopoietic cells from bone marrow of rats and cultured in vitro.Then,the HP-6 was prepared into five concentration gradients of 0.0001 mg/mL,0.001 mg/mL,0.01 mg/mL,0.1 mg/mL,and 1 mg/mL,and the hematopoietic cells were cultured in vitro for 24 h and 48 h.Using PBS as the control,detected the proliferation rate of hematopoietic cells after cultured of 24 h and 48 h by MTT.The experimental results showed that five concentration gradients can promote the proliferation of hematopoietic cells,and the proliferation rate increased first and then decreased with the increase of concentration.The proliferation effect of 24h was better than that of 48h,and the proliferation effect was best when the concentration was 0.01mg/mL,reaching 48.79%.Secondly,at the gene level,we analyzed the expression of proliferation factor Foxm1 of hematopoietic cells treated by HP-6 through the semi-quantitative PCR and real-time fluorescence quantitative PCR.The semi-quantitative PCR results showed that the expression of Foxm1 gene was increased after the hematopoietic cells were treated with different concentrations of HP-6.In order to more accurately understand the effect of HP-6 on Foxml expression,we also carried out the real-time fluorescence quantitative PCR.The results showed that different concentrations of HP-6 can increase the expression level of Foxm1 gene.When the active peptide concentration was 0.01mg/mL,the expression level of Foxm1 gene was 1.76 times higher than that of control group(PBS).Therefore,the microalgae-derived active peptide HP-6 can promote the proliferation of hematopoietic cells by regulating the level of the Foxml gene.Thirdly,performed the non-clinical pharmacokinetic studies of HP-6.Rats were intraperitoneal injected with 10.0mg/kg active peptide HP-6.After 1h,4h and 24h,use LC-MS to detect the tissue distribution of HP-6 in rats;rat feces were collected at 0-4h,4-8h,8-12h,12-24h,24-36h,36-48h,48-72h,then use LC-MS to detect excretion of HP-6 in the feces of rats.The results showed that rats were intraperitoneal injected with 10.0mg/kg of active peptide HP-6,after 1h,4h and 24h,the HP-6 was detected in the heart,liver,spleen,lung,kidney,large intestine,small intestine,stomach,brain and bone marrow of rats,and the content of active peptide was the largest in bone marrow;in addition,HP-6 was detected in the rat feces,during the period of 24-36h,the excretion of HP-6 in the feces was the most and the rate of excretion was the greatest.To sum up,this research provides a certain experimental basis and theoretical basis for the realization of the medicinal value of HP-6 in the future.