scholarly journals Nanofiber-mediated sequential photothermal antibacteria and macrophage polarization for healing MRSA-infected diabetic wounds

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhou Xu ◽  
Bin Deng ◽  
Xuewen Wang ◽  
Jie Yu ◽  
Zhuobin Xu ◽  
...  

Abstract Background Diabetic wound healing remains a challenge because of its susceptibility to drug-resistant bacterial infection and its persistent proinflammatory state. Switching from proinflammatory M1 macrophages (Mφs) to proregenerative M2 dominant Mφs in a timely manner accelerates wound healing by coordinating inflammatory, proliferative, and angiogenic processes. Methods We propose a sequential photothermal antibacterial and subsequent M2 Mφ polarization strategy based on nanofibers (NFs) consisting of polydopamine (PDA) coating on curcumin (Cur) nanocrystals to treat Methicillin-resistant Staphylococcus aureus (MRSA)-infected diabetic wounds. Results The PDA/Cur NFs showed excellent photothermal conversion and antibacterial effects due to the PDA shell under laser irradiation, consequently resulting in the release of the inner Cur with the ability to promote cell proliferation and reinforce the M2 Mφ phenotype in vitro. In vivo studies on MRSA-infected diabetic wounds showed that PDA/Cur NFs not only inhibited MRSA infection but also accelerated the wound regeneration process. Furthermore, the NFs displayed the ability to promote the M2 Mφ phenotype with enhanced collagen deposition, angiogenesis, and cell proliferation. Conclusion Overall, the NFs displayed great potential as promising therapeutics for healing infected diabetic wounds through a sequential photothermal antibacterial and M2 Mφ polarization strategy. Graphical abstract

2021 ◽  
Vol 12 (6) ◽  
pp. 7621-7632

Diabetes Mellitus is the most prevalent metabolic disorder that is increasing at an alarming rate worldwide. The unregulated glucose level leads to various types of health disorders, and one of the major diabetic complications is delayed wound healing. Due to the more side effects of synthetic drugs, there is a need to explore plants and their phytochemicals for medicinal purposes. It was found that Quercetin, a flavonoid, increases the rate of diabetic wound healing by enhancing the expression of SIRT1. This demands more insight towards Quercetin and its similar compounds, as it is hypothesized that similar compounds may have similar biological properties. Thus similarity searching was done to identify the most similar compounds of Quercetin, and then the molecular docking of the screened compounds was performed using AutoDock Vina. The unique ligands were docked into the active site of SIRT1 protein (PDB ID: 4ZZJ). The binding free energy of the interacting ligand with the protein was estimated. Six compounds were identified which possess the maximum structural similarity with Quercetin, and upon docking, it was found that gossypetin and herbacetin have similar binding modes and binding energy as that of Quercetin (-7.5 kcal/mol). Therefore, the hypothesis has been validated by in silico analysis. Our study identified two phytochemicals, Gossypetin, and Herbacetin which can prove beneficial for improving diabetic wound healing but needs to be validated further by in vitro and in vivo studies.


2021 ◽  
Author(s):  
Jiankai Li ◽  
Tianshuai Zhang ◽  
Mingmang Pan ◽  
Feng Xue ◽  
Fang Lv ◽  
...  

Abstract Impaired angiogenesis is one of the predominant reasons for non-healing diabetic wounds. Herein, a nanofiber/ hydrogel core-shell scaffold with three-dimensional (3D) multilayer patterned structure (3D-PT-P/GM) was introduced for promoting diabetic wound healing with improved angiogenesis. The results showed that the 3D-PT-P/GM scaffolds possessed multilayered structure with interlayer spacing of about 15-80 μm, and the hexagonal micropatterned structures were uniformly distributed on the surface of each layer. The nanofibers in the scaffold exhibited distinct core-shell structures with Gelatin methacryloyl (GelMA) hydrogel as the shell and Poly (D, L-lactic acid) (PDLLA) as the core. The results showed that the porosity, water retention time and water vapor permeability of the 3D-PT-P/GM scaffolds increased to 1.6 times, 21 times, and 1.9 times than that of the two-dimensional (2D) PDLLA nanofibrous scaffolds, respectively. The in vitro studies showed that the 3D-PT-P/GM scaffolds could significantly promote cell adhesion, proliferation, infiltration and migration throughout the scaffolds, and the expression of cellular communication protein-related genes, as well as angiogenesis-related genes in the same group, was remarkably upregulated. The in vivo results further demonstrated that the 3D-PT-P/GM scaffolds could not only effectively absorb exudate and provide a moist environment for the wound sites, but also significantly promote the formation of a 3D network of capillaries. As a result, the healing of diabetic wounds was accelerated with enhanced angiogenesis, granulation tissue formation, and collagen deposition. These results indicate that nanofiber/ hydrogel core-shell scaffolds with 3D multilayer patterned structures could provide a new strategy for facilitating chronic wound healing.


2021 ◽  
Author(s):  
Sheikh Tanzina Haque ◽  
Subbroto Kumar Saha ◽  
Md. Enamul Haque ◽  
Nirupam Biswas

Diabetic wounds often presage chronic complications that are difficult to treat. Unfortunately, existing conventional treatment modalities often warrant unpremeditated side effects, given the need to develop alternative therapeutic phenotypes that...


2020 ◽  
Vol 133 (19) ◽  
pp. jcs235838
Author(s):  
Peilang Yang ◽  
Xiqiao Wang ◽  
Di Wang ◽  
Yan Shi ◽  
Meng Zhang ◽  
...  

ABSTRACTBesides regulating glucose levels, insulin has been reported to participate actively in many other functions, including modulating inflammatory reactions. In this study we investigated how topical insulin application would affect the diabetic wound healing process. We found that the excessive expression of insulin-degrading enzyme led to insufficient insulin levels in diabetic skin during wound healing, which ultimately reduced the recovery rate of diabetic wounds. We confirmed that topical insulin application could reverse the impaired inflammation reaction in the diabetic wound environment and promote healing of diabetic wounds. Our study revealed that insulin promoted apoptosis of neutrophils and subsequently triggered polarization of macrophages. Both in vivo and in vitro studies verified that insulin re-established phagocytosis function and promoted the process of phagocytosis-induced apoptosis in neutrophils. Furthermore, we found that insulin treatment also promoted efferocytosis of the apoptosed neutrophils by macrophages, and thus induced macrophages to change their polarization state from M1 to M2. In conclusion, our studies proved that the exogenous application of insulin could improve diabetic wound healing via the restoration of the inflammatory response.


2020 ◽  
Vol 17 (162) ◽  
pp. 20190712 ◽  
Author(s):  
Muhammet Emin Cam ◽  
Sila Yildiz ◽  
Hussain Alenezi ◽  
Sumeyye Cesur ◽  
Gul Sinemcan Ozcan ◽  
...  

In order to provide more effective treatment strategies for the rapid healing of diabetic wounds, novel therapeutic approaches need to be developed. The therapeutic potential of peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist pioglitazone hydrochloride (PHR) in two different release kinetic scenarios, burst release and sustained release, was investigated and compared with in vitro and in vivo tests as potential wound healing dressings. PHR-loaded fibrous mats were successfully fabricated using polyvinyl-pyrrolidone and polycaprolactone by scalable pressurized gyration. The results indicated that PHR-loaded fibrous mats expedited diabetic wound healing in type-1 diabetic rats and did not show any cytotoxic effect on NIH/3T3 (mouse embryo fibroblast) cells, albeit with different release kinetics and efficacies. The wound healing effects of fibrous mats are presented with histological and biochemical evaluations. PHR-loaded fibrous mats improved neutrophil infiltration, oedema, and inflammation and increased epidermal regeneration and fibroblast proliferation, but the formation of hair follicles and completely improved oedema were observed only in the sustained release form. Thus, topical administration of PPAR-γ agonist in sustained release form has high potential for the treatment of diabetic wounds in inflammatory and proliferative phases of healing with high bioavailability and fewer systemic side effects.


2021 ◽  
Author(s):  
Qian Wei ◽  
Yaxi Wang ◽  
Kui Ma ◽  
Xiaowei Bian ◽  
Qiankun Li ◽  
...  

Abstract Background: Endothelial dysfunction caused by persistent hyperglycemia in diabetes is responsible for impaired angiogenesis in diabetic wounds. Exosomes are considered potential therapeutic tools to promote diabetic wound healing. The aim of this study was to investigate the effects of exosomes secreted by human umbilical cord mesenchymal stem cells (hucMSC-Exos) on angiogenesis under high glucose (HG) conditions in vivo and in vitro and to explore the underlying mechanisms.Methods: HucMSC-Exos were used to treat diabetic wounds and human umbilical vascular endothelial cells (HUVECs) exposed to HG. Wound healing and angiogenesis were assessed in vivo. The biological characteristics of HUVECs were examined in vitro. Expression of pro-angiogenesis genes in HUVECs was also examined by western blotting. The miRNAs contained within hucMSC-Exos were identified using miRNA microarrays and qRT-PCR. The roles of selected miRNAs in angiogenesis were assessed using specific agomirs and inhibitors.Results: In vivo, local application of hucMSC-Exos enhanced wound healing and angiogenesis. In vitro, hucMSC-Exos reduced senescence of HG-treated HUVECs and promoted proliferation, migration, and tube formation by inhibiting phosphatase and tensin homolog (PTEN) expression and activating the AKT/HIF-1α/VEGF pathways. MiR-221-3p was enriched in hucMSC-Exos. In vitro, MiR-221-3p downregulated PTEN and activated the AKT/HIF-1α/VEGF pathway to promote proliferation, migration, and tube formation in HG-treated HUVECs. In vivo, miR-221-3p agomirs mimicked the effects of hucMSC-Exos on wound healing and angiogenesis, whereas miR-221-3p inhibitors reversed their effects.Conclusions: Our findings suggest that hucMSC-Exos have regenerative and protective effects on HG-induced senescence in endothelial cells via transfer of miR-221-3p, thereby accelerating diabetic wound healing. Thus, hucMSC-Exos may be promising therapeutic candidates for improving diabetic wound angiogenesis.


2022 ◽  
Vol 20 (1) ◽  
Author(s):  
Jiankai Li ◽  
Tianshuai Zhang ◽  
Mingmang Pan ◽  
Feng Xue ◽  
Fang Lv ◽  
...  

AbstractImpaired angiogenesis is one of the predominant reasons for non-healing diabetic wounds. Herein, a nanofiber/hydrogel core–shell scaffold with three-dimensional (3D) multilayer patterned structure (3D-PT-P/GM) was introduced for promoting diabetic wound healing with improved angiogenesis. The results showed that the 3D-PT-P/GM scaffolds possessed multilayered structure with interlayer spacing of about 15–80 μm, and the hexagonal micropatterned structures were uniformly distributed on the surface of each layer. The nanofibers in the scaffold exhibited distinct core–shell structures with Gelatin methacryloyl (GelMA) hydrogel as the shell and Poly (d, l-lactic acid) (PDLLA) as the core. The results showed that the porosity, water retention time and water vapor permeability of the 3D-PT-P/GM scaffolds increased to 1.6 times, 21 times, and 1.9 times than that of the two-dimensional (2D) PDLLA nanofibrous scaffolds, respectively. The in vitro studies showed that the 3D-PT-P/GM scaffolds could significantly promote cell adhesion, proliferation, infiltration and migration throughout the scaffolds, and the expression of cellular communication protein-related genes, as well as angiogenesis-related genes in the same group, was remarkably upregulated. The in vivo results further demonstrated that the 3D-PT-P/GM scaffolds could not only effectively absorb exudate and provide a moist environment for the wound sites, but also significantly promote the formation of a 3D network of capillaries. As a result, the healing of diabetic wounds was accelerated with enhanced angiogenesis, granulation tissue formation, and collagen deposition. These results indicate that nanofiber/hydrogel core–shell scaffolds with 3D multilayer patterned structures could provide a new strategy for facilitating chronic wound healing. Graphical Abstract


2020 ◽  
Vol 21 (16) ◽  
pp. 5599 ◽  
Author(s):  
Hannah M Thomas ◽  
Parinaz Ahangar ◽  
Benjamin R Hofma ◽  
Xanthe L Strudwick ◽  
Robert Fitridge ◽  
...  

Pericytes are peri-vascular mural cells which have an important role in the homeostatic regulation of inflammatory and angiogenic processes. Flightless I (Flii) is a cytoskeletal protein involved in regulating cellular functions, but its involvement in pericyte activities during wound healing is unknown. Exacerbated inflammation and reduced angiogenesis are hallmarks of impaired diabetic healing responses, and strategies aimed at regulating these processes are vital for improving healing outcomes. To determine the effect of altering Flii expression on pericyte function, in vitro and in vivo studies were performed to assess the effect on healing, inflammation and angiogenesis in diabetic wounds. Here, we demonstrated that human diabetic wounds display upregulated expression of the Flii protein in conjunction with a depletion in the number of platelet derived growth factor receptor β (PDGFRβ) +/ neural glial antigen 2 (NG2) + pericytes present in the dermis. Human pericytes were found to be positive for Flii and attenuating its expression in vitro through siRNA knockdown led to enhanced proliferation, migration and angiogenic functions. Genetic knockdown of Flii in a streptozotocin-induced murine model of diabetes led to increased numbers of pericytes within the wound. This was associated with dampened inflammation, an increased rate of angiogenic repair and improved wound healing. Our findings show that Flii expression directly impacts pericyte functions, including proliferation, motility and angiogenic responses. This suggests that Flii regulation of pericyte function may be in part responsible for the changes in pericyte-related processes observed in diabetic wounds.


2020 ◽  
Vol 19 (17) ◽  
pp. 2108-2119
Author(s):  
Yang Jin ◽  
Li Lv ◽  
Shu-Xiang Ning ◽  
Ji-Hong Wang ◽  
Rong Xiao

Background: Laryngeal Squamous Cell Carcinoma (LSCC) is a malignant epithelial tumor with poor prognosis and its incidence rate increased recently. rLj-RGD3, a recombinant protein cloned from the buccal gland of Lampetra japonica, contains three RGD motifs that could bind to integrins on the tumor cells. Methods: MTT assay was used to detect the inhibitory rate of viability. Giemsa’s staining assay was used to observe the morphological changes of cells. Hoechst 33258 and TUNEL staining assay, DNA ladder assay were used to examine the apoptotic. Western blot assay was applied to detect the change of the integrin signal pathway. Wound-healing assay, migration, and invasion assay were used to detect the mobility of Hep2 cells. H&E staining assay was used to show the arrangement of the Hep2 cells in the solid tumor tissues. Results: In the present study, rLj-RGD3 was shown to inhibit the viability of LSCC Hep2 cells in vitro by inducing apoptosis with an IC50 of 1.23µM. Western blot showed that the apoptosis of Hep2 cells induced by rLj- RGD3 was dependent on the integrin-FAK-Akt pathway. Wound healing, transwells, and western blot assays in vitro showed that rLj-RGD3 suppressed the migration and invasion of Hep2 cells by integrin-FAKpaxillin/ PLC pathway which could also affect the cytoskeleton arrangement in Hep2 cells. In in vivo studies, rLj-RGD3 inhibited the growth, tumor volume, and weight, as well as disturbed the tissue structure of the solid tumors in xenograft models of BALB/c nude mice without reducing their body weights. Conclusion: hese results suggested that rLj-RGD3 is an effective and safe suppressor on the growth and metastasis of LSCC Hep2 cells from both in vitro and in vivo experiments. rLj-RGD3 might be expected to become a novel anti-tumor drug to treat LSCC patients in the near future.


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