BACKGROUND:Nanocell vesicles possess functions such as re-epithelialization,antioxidation,anti-inflammation,and regulation of extracellular matrix remodeling.Meanwhile,apoptotic bodies have the immunomodulatory effects.Therefore,the combination of the two to form nanofusion vesicles can synergistically promote the healing of diabetic skin wounds.OBJECTIVE:To elucidate the impact of nanofusion vesicles on skin wound healing in a diabetic murine model.METHODS:(1)Material preparation and characterization:The primary bone marrow mesenchymal stem cells of C57BL/6J neonatal mice and the neutrophil apoptotic bodies of C57BL/6J mice were isolated and extracted.The nanofusion vesicles were prepared by micro-extrusion mechanism.(2)In vitro experiment:MTT assay was used to detect the proliferative effect of different concentrations of nanofusion vesicles on NIH-3T3 cells and human umbilical vein endothelial cells.Reactive oxygen species fluorescence probe was used to detect the antioxidant effect of nano-fusion vesicles on NIH-3T3 cells treated with hydrogen peroxide(H2O2).The inhibitory effect of nanofusion vesicles on RAW 264.7 macrophage inflammation induced by lipopolyside was detected by real-time quantitative RT-qPCR.(3)In vivo experiment:36 male C57BL/6J mice were employed to develop a murine model of diabetes mellitus.Following the successful induction of diabetes,two circular full-thickness wounds,each with a diameter of 6 mm,were created on either side of the diabetic mice's spine using a skin punch.The mice were divided into three groups by random number table method.The control group was injected with 0.1 mL of phosphate buffer solution.The nanovesicle group was injected with 0.1 mL nanovesicles(25 μg/mL).The nanofusion vesicle group was injected with 0.1 mL nanofusion(25 μg/mL)vesicles.After treatment for three consecutive days,the wound healing and histomorphological changes were observed.RESULTS AND CONCLUSION:(1)In vitro experiment:nanofusion vesicles,when administered at concentrations ranging from 0 to 100 μg/mL,exhibited no toxic effects and promoted the proliferation of NIH-3T3 and HUVEC cell lines.Notably,a concentration of 25 μg/mL nanofusion vesicle significantly enhanced the proliferation of NIH-3T3 cells.Furthermore,the survival rate of human umbilical vein endothelial cells was observed to increase in correlation with escalating concentrations of nanofusion vesicles.Nanofusion vesicles had a good antioxidant effect.In comparison to the H2O2 group,the fluorescence signal indicative of reactive oxygen species was progressively diminished in both the nanovesicle group and the nanofusion vesicle group.Furthermore,nanofusion vesicles possessed anti-inflammatory capabilities,effectively mitigating the inflammatory response in macrophages triggered by lipopolysaccharide stimulation.(2)In vivo experiment:Hematoxylin-eosin and Masson's trichrome staining revealed that in comparison to the control group,both the nanovesicle group and the nanofusion vesicle group exhibited a significant increase in granulation tissue formation and collagen fiber deposition within the wounds by day 6.Notably,the nanofusion vesicle group displayed the most pronounced effects.On day 12,the wound of nanofusion vesicle group was significantly reduced,and the healing rate was significantly faster than that of other groups(P＜0.01),and the effect of promoting wound healing was the most significant.Our findings demonstrated that nanofusion vesicles exhibited superior pro-cell proliferative,antioxidant,and anti-inflammatory properties,thereby exerting a beneficial effect on the promotion of skin wound healing in diabetic mouse models.

BACKGROUND:Nanocell vesicles possess functions such as re-epithelialization,antioxidation,anti-inflammation,and regulation of extracellular matrix remodeling.Meanwhile,apoptotic bodies have the immunomodulatory effects.Therefore,the combination of the two to form nanofusion vesicles can synergistically promote the healing of diabetic skin wounds.OBJECTIVE:To elucidate the impact of nanofusion vesicles on skin wound healing in a diabetic murine model.METHODS:(1)Material preparation and characterization:The primary bone marrow mesenchymal stem cells of C57BL/6J neonatal mice and the neutrophil apoptotic bodies of C57BL/6J mice were isolated and extracted.The nanofusion vesicles were prepared by micro-extrusion mechanism.(2)In vitro experiment:MTT assay was used to detect the proliferative effect of different concentrations of nanofusion vesicles on NIH-3T3 cells and human umbilical vein endothelial cells.Reactive oxygen species fluorescence probe was used to detect the antioxidant effect of nano-fusion vesicles on NIH-3T3 cells treated with hydrogen peroxide(H2O2).The inhibitory effect of nanofusion vesicles on RAW 264.7 macrophage inflammation induced by lipopolyside was detected by real-time quantitative RT-qPCR.(3)In vivo experiment:36 male C57BL/6J mice were employed to develop a murine model of diabetes mellitus.Following the successful induction of diabetes,two circular full-thickness wounds,each with a diameter of 6 mm,were created on either side of the diabetic mice's spine using a skin punch.The mice were divided into three groups by random number table method.The control group was injected with 0.1 mL of phosphate buffer solution.The nanovesicle group was injected with 0.1 mL nanovesicles(25 μg/mL).The nanofusion vesicle group was injected with 0.1 mL nanofusion(25 μg/mL)vesicles.After treatment for three consecutive days,the wound healing and histomorphological changes were observed.RESULTS AND CONCLUSION:(1)In vitro experiment:nanofusion vesicles,when administered at concentrations ranging from 0 to 100 μg/mL,exhibited no toxic effects and promoted the proliferation of NIH-3T3 and HUVEC cell lines.Notably,a concentration of 25 μg/mL nanofusion vesicle significantly enhanced the proliferation of NIH-3T3 cells.Furthermore,the survival rate of human umbilical vein endothelial cells was observed to increase in correlation with escalating concentrations of nanofusion vesicles.Nanofusion vesicles had a good antioxidant effect.In comparison to the H2O2 group,the fluorescence signal indicative of reactive oxygen species was progressively diminished in both the nanovesicle group and the nanofusion vesicle group.Furthermore,nanofusion vesicles possessed anti-inflammatory capabilities,effectively mitigating the inflammatory response in macrophages triggered by lipopolysaccharide stimulation.(2)In vivo experiment:Hematoxylin-eosin and Masson's trichrome staining revealed that in comparison to the control group,both the nanovesicle group and the nanofusion vesicle group exhibited a significant increase in granulation tissue formation and collagen fiber deposition within the wounds by day 6.Notably,the nanofusion vesicle group displayed the most pronounced effects.On day 12,the wound of nanofusion vesicle group was significantly reduced,and the healing rate was significantly faster than that of other groups(P＜0.01),and the effect of promoting wound healing was the most significant.Our findings demonstrated that nanofusion vesicles exhibited superior pro-cell proliferative,antioxidant,and anti-inflammatory properties,thereby exerting a beneficial effect on the promotion of skin wound healing in diabetic mouse models.

BACKGROUND:MXene nanoparticles,due to their unique hydrophilicity,biocompatibility,and antibacterial properties,are widely used in wound,tumor,nerve repair,and cardiovascular treatments.However,it is still unclear what effect MXene nanoparticles have on diabetic wound healing.OBJECTIVE:To investigate the in vitro antioxidant,anti-inflammatory and photothermal antibacterial properties of MXene nanoparticles Ti3C2Tx as well as their effect on wound repair in diabetic mice.METHODS:(1)In vitro experiments:The cytotoxicity of Ti3C2Tx nanoparticles on mouse fibroblasts(NIH-3T3)at various concentrations was evaluated using the methyl thiazolyl tetrazolium(MTT)assay.NIH-3T3 cells were exposed to H2O2,and the MTT assay was used to detect the protective effects of different mass concentrations of Ti3C2Tx on NIH-3T3 cells.NIH-3T3 cells were exposed to H2O2,and the effect of Ti3C2Tx(20 μg/mL)on the generation of reactive oxygen species in NIH-3T3 cells was analyzed under illumination(or no illumination)treatment.RAW264.7 macrophages were divided into three groups:control group,lipopolysaccharide group,and lipopolysaccharide+Ti3C2Tx group.Real-time quantitative PCR was used to detect the expression of specific genes(CD86,interleukin 6,CD206,arginase 1)in the cells.Escherichia coli(or Staphylococcus aureus)were divided into three groups:control group,Ti3C2Tx group,and Ti3C2Tx illumination group.The bacterial survival rate was calculated by plate colony counting method.(2)In vivo experiments:Streptozotocin was administered intraperitoneally to ICR mice to induce a diabetic condition.After successful modeling,a full-thickness skin defect wound was created on the back of the mice using a circular punch.The experiment was divided into three groups:control group(n=6),Ti3C2Tx group(n=6),and Ti3C2Tx illumination group(n=6).The wound healing was observed,and CD31 and CD206 immunohistochemical staining of wound tissue was performed on day 7 after intervention.Hematoxylin-eosin staining and Masson staining of wound tissue were performed on days 7 and 14 after intervention.Ti3C2Tx solution was injected subcutaneously into ICR mice.After illumination(or non-illumination)exposure,the toxic effects of Ti3C2Tx on mice were analyzed by blood biochemical detection.RESULTS AND CONCLUSION:(1)In vitro experiments:Ti3C2Tx showed no cytotoxicity on NIH-3T3 cells at mass concentrations ranging from 5-160 μg/mL.It increased the survival rate of NIH-3T3 cells at a mass concentration of 20 μg/mL.Ti3C2Tx at 10-80 μg/mL significantly improved the survival rate of NIH-3T3 cells under H2O2 intervention.Ti3C2Tx significantly inhibited the generation of reactive oxygen species in NIH-3T3 cells under the intervention of H2O2,and illumination treatment further enhanced the effect of Ti3C2Tx on inhibiting the generation of reactive oxygen species.Ti3C2Tx effectively inhibited macrophage inflammation induced by lipopolysaccharide and promoted the transformation of cells into M2 macrophages with anti-inflammatory properties.Both Ti3C2Tx and Ti3C2Tx illumination significantly inhibited the growth of Escherichia coli and Staphylococcus aureus,and the inhibitory effect of Ti3C2Tx illumination was more significant.(2)In vivo experiments:Gross and histological analyses of the wound surface showed that both Ti3C2Tx and Ti3C2Tx illumination promoted wound healing in diabetic mice,and the promotion effect of Ti3C2Tx irradiation was more significant.Immunohistochemical staining results showed that both Ti3C2Tx and Ti3C2Tx illumination inhibited the inflammatory response in diabetic wounds and promoted angiogenesis,and the effect of Ti3C2Tx illumination was more significant.Blood biochemical test results showed that Ti3C2Tx and illumination had no obvious toxic effects on mice.(3)These results indicate that Ti3C2Tx nanoparticles efficiently promote the healing of skin wounds in a diabetic mouse model through antioxidation,anti-inflammation,and antibacterial actions via photothermal effects.

BACKGROUND:MXene nanoparticles,due to their unique hydrophilicity,biocompatibility,and antibacterial properties,are widely used in wound,tumor,nerve repair,and cardiovascular treatments.However,it is still unclear what effect MXene nanoparticles have on diabetic wound healing.OBJECTIVE:To investigate the in vitro antioxidant,anti-inflammatory and photothermal antibacterial properties of MXene nanoparticles Ti3C2Tx as well as their effect on wound repair in diabetic mice.METHODS:(1)In vitro experiments:The cytotoxicity of Ti3C2Tx nanoparticles on mouse fibroblasts(NIH-3T3)at various concentrations was evaluated using the methyl thiazolyl tetrazolium(MTT)assay.NIH-3T3 cells were exposed to H2O2,and the MTT assay was used to detect the protective effects of different mass concentrations of Ti3C2Tx on NIH-3T3 cells.NIH-3T3 cells were exposed to H2O2,and the effect of Ti3C2Tx(20 μg/mL)on the generation of reactive oxygen species in NIH-3T3 cells was analyzed under illumination(or no illumination)treatment.RAW264.7 macrophages were divided into three groups:control group,lipopolysaccharide group,and lipopolysaccharide+Ti3C2Tx group.Real-time quantitative PCR was used to detect the expression of specific genes(CD86,interleukin 6,CD206,arginase 1)in the cells.Escherichia coli(or Staphylococcus aureus)were divided into three groups:control group,Ti3C2Tx group,and Ti3C2Tx illumination group.The bacterial survival rate was calculated by plate colony counting method.(2)In vivo experiments:Streptozotocin was administered intraperitoneally to ICR mice to induce a diabetic condition.After successful modeling,a full-thickness skin defect wound was created on the back of the mice using a circular punch.The experiment was divided into three groups:control group(n=6),Ti3C2Tx group(n=6),and Ti3C2Tx illumination group(n=6).The wound healing was observed,and CD31 and CD206 immunohistochemical staining of wound tissue was performed on day 7 after intervention.Hematoxylin-eosin staining and Masson staining of wound tissue were performed on days 7 and 14 after intervention.Ti3C2Tx solution was injected subcutaneously into ICR mice.After illumination(or non-illumination)exposure,the toxic effects of Ti3C2Tx on mice were analyzed by blood biochemical detection.RESULTS AND CONCLUSION:(1)In vitro experiments:Ti3C2Tx showed no cytotoxicity on NIH-3T3 cells at mass concentrations ranging from 5-160 μg/mL.It increased the survival rate of NIH-3T3 cells at a mass concentration of 20 μg/mL.Ti3C2Tx at 10-80 μg/mL significantly improved the survival rate of NIH-3T3 cells under H2O2 intervention.Ti3C2Tx significantly inhibited the generation of reactive oxygen species in NIH-3T3 cells under the intervention of H2O2,and illumination treatment further enhanced the effect of Ti3C2Tx on inhibiting the generation of reactive oxygen species.Ti3C2Tx effectively inhibited macrophage inflammation induced by lipopolysaccharide and promoted the transformation of cells into M2 macrophages with anti-inflammatory properties.Both Ti3C2Tx and Ti3C2Tx illumination significantly inhibited the growth of Escherichia coli and Staphylococcus aureus,and the inhibitory effect of Ti3C2Tx illumination was more significant.(2)In vivo experiments:Gross and histological analyses of the wound surface showed that both Ti3C2Tx and Ti3C2Tx illumination promoted wound healing in diabetic mice,and the promotion effect of Ti3C2Tx irradiation was more significant.Immunohistochemical staining results showed that both Ti3C2Tx and Ti3C2Tx illumination inhibited the inflammatory response in diabetic wounds and promoted angiogenesis,and the effect of Ti3C2Tx illumination was more significant.Blood biochemical test results showed that Ti3C2Tx and illumination had no obvious toxic effects on mice.(3)These results indicate that Ti3C2Tx nanoparticles efficiently promote the healing of skin wounds in a diabetic mouse model through antioxidation,anti-inflammation,and antibacterial actions via photothermal effects.

OBJECTIVETo investigate the relationship between miR-144 and Toll-like receptor 2 (TLR2).

METHODSRT-qPCR was used to determine the expression of TLR2 and its downstream inflammatory cytokine TNF-α in rat macrophage cell line NR8383 transfected by a mimic miR-144 or miR-144 inhibitor. The fragments of 3'UTR region of rat TLR2 mRNA including wild or mutant miR-144 binding site obtained by PCR using rat liver cDNA were ligated to pmirGLO report gene vector digested with SacI and XbaI to construct the recombinant vectors of pmir-TLR2-3'UTR and pmir-mutant-TLR2-3'UTR. The miR-144 targeting TLR2 was further determined by dual luciferase reporter assay and miR-144 mimics.

RESULTSTLR2 and TNF-α in NR8383 cells were decreased after transfection with 100 nmol/L mimic miR-144 for 24 h and increased after transfection with 100 nmol/L miR-144 inhibitor. PCR and double-enzyme digestion with SacI and XbaI confirmed successful insertion of the target fragments. Dual luciferase reporter assay suggested the binding of miR-144 to the 3'UTR of rat TLR2 mRNA.

CONCLUSIONmiR-144 negatively regulates the expression of TLR2 and its down-stream cytokine TNF-α by targeting TLR2 in NR8383 cells.

3' Untranslated Regions ; Animals ; Binding Sites ; Cell Line ; Genetic Vectors ; Luciferases ; Macrophages ; metabolism ; MicroRNAs ; metabolism ; RNA, Messenger ; Rats ; Real-Time Polymerase Chain Reaction ; Toll-Like Receptor 2 ; metabolism ; Transfection ; Tumor Necrosis Factor-alpha ; metabolism

Objective To investigate the relationship between miR-144 and Toll-like receptor 2 (TLR2). Methods RT-qPCR was used to determine the expression of TLR2 and its downstream inflammatory cytokine TNF-α in rat macrophage cell line NR8383 transfected by a mimic miR-144 or miR-144 inhibitor. The fragments of 3'UTR region of rat TLR2 mRNA including wild or mutant miR-144 binding site obtained by PCR using rat liver cDNA were ligated to pmirGLO report gene vector digested with SacI and XbaI to construct the recombinant vectors of pmir-TLR2-3'UTR and pmir-mutant-TLR2-3'UTR. The miR-144 targeting TLR2 was further determined by dual luciferase reporter assay and miR-144 mimics. Results TLR2 and TNF-αin NR8383 cells were decreased after transfection with 100 nmol/L mimic miR-144 for 24 h and increased after transfection with 100 nmol/L miR-144 inhibitor. PCR and double-enzyme digestion with SacI and XbaI confirmed successful insertion of the target fragments. Dual luciferase reporter assay suggested the binding of miR-144 to the 3'UTR of rat TLR2 mRNA. Conclusion miR-144 negatively regulates the expression of TLR2 and its down-stream cytokine TNF-αby targeting TLR2 in NR8383 cells.

Objective To investigate the relationship between miR-144 and Toll-like receptor 2 (TLR2). Methods RT-qPCR was used to determine the expression of TLR2 and its downstream inflammatory cytokine TNF-α in rat macrophage cell line NR8383 transfected by a mimic miR-144 or miR-144 inhibitor. The fragments of 3'UTR region of rat TLR2 mRNA including wild or mutant miR-144 binding site obtained by PCR using rat liver cDNA were ligated to pmirGLO report gene vector digested with SacI and XbaI to construct the recombinant vectors of pmir-TLR2-3'UTR and pmir-mutant-TLR2-3'UTR. The miR-144 targeting TLR2 was further determined by dual luciferase reporter assay and miR-144 mimics. Results TLR2 and TNF-αin NR8383 cells were decreased after transfection with 100 nmol/L mimic miR-144 for 24 h and increased after transfection with 100 nmol/L miR-144 inhibitor. PCR and double-enzyme digestion with SacI and XbaI confirmed successful insertion of the target fragments. Dual luciferase reporter assay suggested the binding of miR-144 to the 3'UTR of rat TLR2 mRNA. Conclusion miR-144 negatively regulates the expression of TLR2 and its down-stream cytokine TNF-αby targeting TLR2 in NR8383 cells.