RESUMEN
Platelets play an important role in physiological and pathological activities such as thrombosis, inflammation and tumorigenesis. At present, the application of platelets in drug delivery systems is increasingly studied. Compared with traditional drug delivery systems, new drug delivery systems based on platelets and their derivatives can effectively improve the circulation time and selective accumulation, and reduce the occurrence of related immune reactions or off-target toxic and side effects. In this paper, the types and applications of platelet and its derivatives drug delivery systems were summarized in order to provide reference for platelet-related drug delivery research.
RESUMEN
【Objective】 To investigate the effect of polymerized human cord hemoglobin (PolyCHb) on the chemosensitivity of human breast cancer MCF-7 cell subcutaneous xenografts in nude mice and its mechanism. 【Methods】 The MCF-7 cells in exponential growth phase were collected and made into suspension cells at a density of 5×107 cells/mL.Subsequently, the cells were inoculated subcutaneously in the right limb of 18 BALB/c-nu nude mice with 0.2 mL cells per mouse to establish subcutaneous xenograft.When the tumor volume reached about 100 mm3, they were randomly divided into chemotherapy group: doxorubicin 5 mg·kg-1, once/week; chemotherapy + PolyCHb group: in addition to doxorubicin (chemotherapy group), PolyCHb 600 mg·kg-1, 3 times/week; the control group: normal saline 90 mg·kg-1, once/week; all were injected through tail vein continuously for 4 weeks.From the day of injection (d 0), the tumor volume of each group of nude mice was measured every 3 days, and the tumor growth curves were drawn accordingly.After 38 days, the tumor growth observation was completed.The tumor was removed and weighed to calculate the tumor inhibition rate.HE staining, immunohistochemistry and TUNEL method were used to observe the pathological changes of tumor tissue, detect the expression of HIF-1α, and detect tumor cell apoptosis respectively.The content of reactive oxygen species (ROS) of each group was determined by fluorescence staining. 【Results】 The tumor volume (mm3) of chemotherapy + PolyCHb group, chemotherapy group and the control group at day 38 were 196.35±103.45 vs 316.29±62.88 vs 519.42±177.33 (P<0.05), and the tumor inhibition rate (%) of chemotherapy + PolyCHb treatment group and chemotherapy group was 62.20 vs 39.11, respectively.HE staining and TUNEL detection showed that cell necrosis and apoptosis in the growth area of tumor tissue increased in chemotherapy + PolyCHb group.Immunohistochemistry and fluorescence staining showed that HIF-1α expression in chemotherapy + PolyCHb group decreased and reactive oxygen species (ROS) content increased. 【Conclusion】 PolyCHb increases the chemosensitivity of subcutaneous xenograft in nude mice with breast cancer, and its mechanism may be related to the increase of ROS in tumor tissue and the promotion of tumor cell apoptosis.
RESUMEN
Red blood cells(RBCs), as the most abundant types of blood cells in the blood, have several advantages as a drug delivery system due to their ultra-long circulation half-life, good biocompatibility, and biodegradability. To date, a variety of RBCs-based drug delivery techniques have been developed for the treatment of infection diseases, cancers, chronic diseases, and autoimmune diseases. This review summarized the progress of RBCs related drug delivery systems, and discussed the advantages and disadvantages of different loading methods and their pre-clinical application progress, promoting the research and development of drug delivery.