Research On Antitumor Activity And Mechanism Of Component PBPCⅡ From Polysaccharides Of Bee Pollen Of Carthamus Tinctorius L. In Yunnan

Carthamus Tinctorius L.is a dry flower of Carthamus Tinctorius of Compositae.It has the functions of promoting blood circulation and promoting menstruation,removing blood stasis and relieving pain.It is a plant resource with dual use of medicine and food.Bee pollen is a yellowish mass formed by special processing of germ cells collected from anthers of honey-derived plants by bees.As an effective active component in bee pollen,polysaccharides have many biological activities such as regulating immunity,antioxidant,anti-inflammatory,anti-virus and so on.These biological activities are closely related to the anti-tumor effect.Previous experimental studies in our group have found that PBPCⅡ,a homogeneous component of polysaccharides from bee Pollen of Carthamus Tinctorius,has significant anti-tumor activity in vitro,but whether PBPCⅡ has anti-tumor effect in vivo and the mechanism of action are not clear,so further research is necessary.Objectives:To observe the anti-tumor effect of PBPCⅡ,a component of polysaccharide from bee pollen of Carthamus Tinctorius L.in Yunnan Province,on S180 tumor-bearing mice,and to study its anti-tumor mechanism at cellular and molecular levels.Methods:There were 60 female Kunming mice,bodyweight 18-22 g.Using the tumor block inoculation method,except for the blank control group,the other mice were inoculated with S180 sarcoma tumors under the right axilla to establish the solid tumor model.They were randomly divided into model group,cyclophosphamide(CTX)group(30mg/kg)and PPBCII low,medium and high dose groups(100,200,400 mg/kg),each group with 10 mice.Then the mice were administrated for 14 days.After the lastadministration,each group of the mice were fasted 24h(weren’t fasted water).After weighing and blood collection,the mice were executed by neck amputation.Tumor mass,thymus and spleen tissues were collected and weighed.Tumor inhibition rate and immune organ index were calculated respectively.The expression of IL-1a,IL-2,IL-6,IFN-γ,TNF-α and VEGF in serum of mice was detected by ELISA.The mRNA expression levels of bax,bcl-2,c-myc and p53 related genes in tumor tissues were detected by RT-qPCR.The protein expression levels of Bax,Bcl-2,C-myc and P53 related genes in tumor tissues were detected by Western Blot.The histopathological changes of tumor tissues in S180 mice were also observed by HE staining method.Results:PBPCⅡ can inhibit the growth of tumors in low,middle and high dose groups.The inhibition rates were 37.44%,42.55% and 54.01% respectively.PBPCⅡ can also increase the thymus index and spleen index of mice.ELISA results showed that PBPCⅡ could increase the levels of IL-1α,IL-2,IFN-γ,TNF-α in serum and decrease the levels of IL-6 and VEGF in serum of tumor-bearing mice.RT-qPCR results showed that PBPCⅡ could significantly promote the expression of bax and p53,and decrease the expression of bcl-2 and c-myc.Western Blot results showed that PBPCⅡ could significantly promote the expression of Bax and P53 protein and reduce the expression of Bcl-2 and C-myc protein compared with the tumor model group.Compared with the model group,HE staining showed that the tumor cells of PBPCⅡ group appearing morphological changes of apoptosis and necrosis.Conclusion:PBPCⅡ can significantly inhibit the growth of tumors in S180 sarcoma mice,and has a good anti-tumor effect.Regulating immune function and inducing apoptosis of tumor cells may be one of the mechanisms to exert its anti-tumor effect.