ABSTRACT
Delayed diabetic wound healing has placed an enormous burden on society. The key factors limiting wound healing include unresolved inflammation and impaired angiogenesis. Platelet-rich plasma (PRP) gel, a popular biomaterial in the field of regeneration, has limited applications due to its non-injectable properties and rapid release and degradation of growth factors. Here, we prepared an injectable hydrogel (DPLG) based on PRP and laponite by a simple one-step mixing method. Taking advantages of the non-covalent interactions, DPLG could overcome the limitations of PRP gels, which is injectable to fill irregular injures and could serve as a local drug reservoir to achieve the sustained release of growth factors in PRP and deferoxamine (an angiogenesis promoter). DPLG has an excellent ability in accelerating wound healing by promoting macrophage polarization and angiogenesis in a full-thickness skin defect model in type I diabetic rats and normal rats. Taken together, this study may provide the ingenious and simple bioactive wound dressing with a superior ability to promote wound healing.
ABSTRACT
Chronic diabetic wound remains a critical challenge suffering from the complicated negative microenvironments, such as high-glucose, excessive reactive oxygen species (ROS), hypoxia and malnutrition. Unfortunately, few strategies have been developed to ameliorate the multiple microenvironments simultaneously. In this study, Chlorella sp. (Chlorella) hydrogels were prepared against diabetic wounds. In vitro experiments demonstrated that living Chlorella could produce dissolved oxygen by photosynthesis, actively consume glucose and deplete ROS with the inherent antioxidants, during the daytime. At night, Chlorella was inactivated in situ by chlorine dioxide with human-body harmless concentration to utilize its abundant contents. It was verified in vitro that the inactivated-Chlorella could supply nutrition, relieve inflammation and terminate the oxygen-consumption of Chlorella-respiration. The advantages of living Chlorella and its contents were integrated ingeniously. The abovementioned functions were proven to accelerate cell proliferation, migration and angiogenesis in vitro. Then, streptozotocin-induced diabetic mice were employed for further validation. The in vivo outcomes confirmed that Chlorella could ameliorate the undesirable microenvironments, including hypoxia, high-glucose, excessive-ROS and chronic inflammation, thereby synergistically promoting tissue regeneration. Given the results above, Chlorella is considered as a tailor-made therapeutic strategy for diabetic wound healing.
ABSTRACT
Objective:To evaluate the effects of adipose-derived stem cells (ADSCs) and ADM microparticle on diabetic wound healing.Methods:ADSCs was co-cultured with ADM microparticle in vitro. The models of diabetic nude mice were established by intraperitoneal injection of STZ and the full-thickness skin defects were designed on the back. All 24 diabetic mice were randomly divided into 4 group: experimental groups were transplanted with ADSCs and ADM microparticle and the other groups were transplanted with ADSCs, ADM microparticle and blank control group was set up. On the 7th and 14 th days, the wound healing rate of 3 mice randomly selected from each group was calculated, and the thickness between dermis and epidermis was measured by hematoxylin and eosin staining. The density of neovascularization was measured by immunohistochemical staining. The differences were compared between the groups.Results:Compared to the ADSCs groups, the mice of the experimental groups showed higher cell survival rate. The wound healing rate in the experimental groups was (86.0±2.7)% (7 days) and (98.5±1.1)% (14 days), thicker dermis-epidermis distance was (99.1±1.8) μm (7 days) and (124.3±4.3) μm (14 days) ( P<0.05), and higher density of neovascularization was noted. Conclusions:The transplantation with active ADM microparticle can significantly promote neovascularization and wound healing of diabetic wound.
ABSTRACT
Aim To observe the effectof paeoniflorin (PA) on diabetic wound healing and its mechanisms. Methods A full-thickness skin excision splint model in diabetic mice was used to study the effects of PA on diabetic wound healing and the underlying mechanism. HE staining and Masson staining were used to observe the changes of granulation tissue and collagen in wound tissues. Immunofluorescence technique was employed to detect angiogenesis in wound tissues of diabetic mice. To detect the effects of PA, human umbilical vein endothelial cells ( HUVECs) and mouse fibroblasts were cultured in vitro. MTS, BrdU and scratch assays were used to detect the effects of PA on proliferation and migration. Tube formation assays were used to detect the effects of PA on the tube formation of HUVECs. qPCR was applied to assess the expression of collagen HI, fibronectin and ot-SMA gene. Immunoflu orescence was used to detect the expression of a-SMA. Results Compared with db/db model group, the formation rate of granulation tissues and collagen and the capillary density around the wound of db/db model group treated with PA was significantly higher than that of db/db model group(P <0. 01 ). PA had no significant effect on endothelial cell proliferation, but it could markedly promote endothelial cell migration and tube formation. PA could significantly up-regulate the migration , proliferation, secretion and differentiation of fibroblasts. Conclusions PA can significantly promote diabetic wound healing, which may be related to accelerating the generation of extracellular matrix and promoting angiogenesis.