Due to complex immune and metabolic dysfunctions, diabetic wounds commonly suffer from infection, oxidative stress, impaired angiogenesis, thereby leading to chronic non-healing lesions. Since current therapies remain insufficient, increasing attention has been directed toward mitophagy, a key regulator of energy balance and stress responses, with mitochondrial dysfunction recognized as a critical driver of defective repair. In this study, we explored the therapeutic role of echinacoside (Ech), a phenylethanol glycoside from Echinacea, known for its potent antioxidant, anti-inflammatory, and pro-angiogenic properties, in promoting diabetic wound healing. Network pharmacology analysis was employed to identify the potential targets of Ech in diabetic condition. In vitro, under H2O2-induced oxidative stress, Ech mitigated the functional impairment of human umbilical vein endothelial cells (HUVECs), enhancing their proliferation, migration, angiogenesis, and antioxidant capacity. Mechanistically, Ech restored HUVECs function by activating Parkin-MFN2-mediated mitophagy through ubiquitination and concurrently upregulated USP35 expression, which mitigated excessive mitophagy. These effects were confirmed using the Parkin-dependent mitophagy inhibitor cyclosporin A (CsA) and USP35-specific siRNA (siUSP35). In a diabetic mouse full-thickness cutaneous wound model, Ech treatment significantly activated Parkin-dependent mitophagy, leading to enhanced neovascularization and collagen deposition at wound site, thereby accelerated the healing process of diabetic wounds. Collectively, these findings identify Ech as a promising therapeutic agent for diabetic wound repair and provide mechanistic insights into its regulation of mitophagy to improve antioxidant responses and angiogenesis, offering a foundation for the development of targeted treatment strategies.

Diabetic wound healing remains a significant challenge, due to chronic inflammatory apoptotic cells accumulation. Herein, an immuno-bioenergy regulated hydrogel (CCE) is reported, which converts apoptotic cells into cytokines that facilitate tissue repair. The CCE consisted of a poly(citrate-curcumin) and erastin cross-linked thermosensitive network, which enhanced efferocytosis in dendritic cells (DCs) by the sustained release of erastin and reinforced the cellular energy metabolism by intracellular release of citrate. With the promoted efferocytosis and increased secretion of anti-inflammatory and pro-reparative cytokines, macrophages are effectively polarized towards M2 phenotype via activation of JAK1/STAT3 pathway, while the damaged function of fibroblasts and endothelial cells under high-glucose conditions is restored. Moreover, the released citrate increased intracellular citrate level, modulating the high glucose-induced energy metabolites disturbances and alleviating mitochondrial dysfunction in endothelial cells. Notably, this combination exhibited a synergistic effect in promoting endothelial cells angiogenesis and immunoregulation ability of macrophages. In a diabetic wound model, CCE hydrogel facilitated the diabetic wounds repair, characterized by a reduced inflammation, enhanced angiogenesis and collagen deposition. These outcomes are attributed to immune microenvironment reconstruction through enhanced efferocytosis-mediated clearance of apoptotic cells and M2 polarization of macrophages. This work presents a novel strategy that leverages efferocytosis and the immune microenvironment modulation to facilitate diabetic wounds healing.

Diabetic wounds, characterized by chronic inflammation and impaired angiogenesis, often lead to severe complications such as persistent infections and an elevated risk of amputation, significantly affecting a patient's quality of life. Garcinol, a polyisoprenylated benzophenone derived from the rind of Garcinia indica, exhibits potent anti-inflammatory, angiogenic, and antioxidant effects in various disease models. However, its potential to enhance diabetic wound healing remains unclear. In this research, we firstly used network pharmacology analysis to identify the potential targets of Garcinol in treating diabetic wounds. Cellular study results revealed that Garcinol therapy alleviated high glucose-induced cellular dysfunction and increased the angiogenic potential of human umbilical vein endothelial cells (HUVECs). Additionally, Garcinol substantially downregulated the levels of inflammatory cytokines secreted by macrophages through inhibiting the PI3K/Akt/NF-κB signaling pathway, which was further validated using the PI3K/Akt agonist 740 YP. Furthermore, inhibiting PI3K signaling also resulted in a marked reduction of NLRP3 inflammasome-mediated pyroptosis in macrophages compared to control. In vivo study using a full-thickness diabetic wound model confirmed that Garcinol treatment promoted diabetic wound healing by improving angiogenesis, inhibiting inflammation and pyroptosis, whereas the addition of 740 YP reduced the beneficial effects of Garcinol. Overall, our findings suggested that Garcinol enhanced diabetic wound healing via its anti-inflammatory ability, suppression of pyroptosis, and enhancement of angiogenesis. These results highlight the potential of Garcinol as a therapeutic agent for diabetic wounds.

Hypertrophic scars affect a significant number of individuals annually, giving rise to both cosmetic concerns and functional impairments. Prior research has established that an imbalance in the composition of gut microbes, termed microbial dysbiosis, can initiate the progression of various diseases through the intricate interplay between gut microbiota and the host. However, the precise nature of the causal link between gut microbiota and hypertrophic scarring remains uncertain. In this study, after compiling summary data from genome-wide association studies (GWAS) involving 418 instances of gut microbiota and hypertrophic scarring, we conducted a bidirectional Mendelian randomization (MR) to investigate the potential existence of a causal relationship between gut microbiota and the development of hypertrophic scar and to discern the directionality of causation. By utilizing MR analysis, we identified seven causal associations between gut microbiome and hypertrophic scarring, involving one positive and six negative causal directions. Among them, Intestinimonas, Ruminococcus2, Barnesiella, Dorea, Desulfovibrio piger, and Ruminococcus torques act as protective factors against hypertrophic scarring, while Eubacterium rectale suggests a potential role as a risk factor for hypertrophic scars. Additionally, sensitivity analyses of these results revealed no indications of heterogeneity or pleiotropy. The findings of our MR study suggest a potential causative link between gut microbiota and hypertrophic scarring, opening up new ways for future mechanistic research and the exploration of nanobiotechnology therapies for skin disorders.

BACKGROUND AND AIM:Necrosis of random-pattern flaps restricts their application in clinical practice. Puerarin has come into focus due to its promising therapeutic effects in ischemic diseases. Here, we employed Puerarin and investigated its role and potential mechanisms in flap survival.EXPERIMENTAL PROCEDURE:The effect of Puerarin on the viability of human umbilical vein endothelial cells (HUVECs) was assessed by CCK-8, EdU staining, migration, and scratch assays. Survival area measurement and laser Doppler blood flow (LDBF) were utilized to assess the viability of ischemic injury flaps. Levels of molecules related to oxidative stress, pyroptosis, autophagy, transcription factor EB (TFEB), and the AMPK-TRPML1-Calcineurin signaling pathway were detected using western blotting, immunofluorescence, dihydroethidium (DHE) staining, RT-qPCR and Elisa.KEY RESULTS:The findings demonstrated that Puerarin enhanced the survivability of ischemic flaps. Autophagy, oxidative stress, and pyroptosis were implicated in the ability of Puerarin in improving flap survival. Increased autophagic flux and augmented tolerance to oxidative stress contribute to Puerarin's suppression of pyroptosis. Additionally, Puerarin modulated the activity of TFEB through the AMPK-TRPML1-Calcineurin signaling pathway, thereby enhancing autophagic flux.CONCLUSIONS AND IMPLICATIONS:Puerarin promoted flap survival from ischemic injury through upregulation of TFEB-mediated autophagy and inhibition of oxidative stress. Our findings offered valuable support for the clinical application of Puerarin in the treatment of ischemic diseases, including random-pattern flaps.

Plastic and reconstructive surgeons frequently utilize random skin flap transplantation to repair skin defects. However, the procedure carries a substantial risk of necrosis. Previous research has suggested that Biliverdin (Bv), the main component of Calculus Bovis, possessed potent anti-ischemic properties, making it a potential therapeutic agent for skin flap survival. Hence, in this study, the potential of Bv in promoting flap survival has been comprehensively investigated. Network pharmacology analysis revealed that the pharmacological effects of Bv on ischemic diseases may be attributed to its modulation of various signaling molecules, including the PI3K-Akt pathway. In vitro results demonstrated that Bv treatment significantly promoted angiogenesis in human umbilical vein endothelial cells (HUVEC), even in the presence of H2O2. This was evident by the increased cell proliferation, enhanced migration, and improved tube formation. Bv also effectively attenuated the intracellular generation of reactive oxygen species (ROS) induced by H2O2, which was achieved by suppressing mitochondrial ROS production through the PI3K/Akt-mediated activation of Nrf2/HO-1 signaling pathway. Consequently, Bv treatment led to a significant reduction in apoptosis and an increase in cell viability of HUVEC. Furthermore, in vivo experiment demonstrated that Bv treatment vastly elevated flap survival through enhancing angiogenesis while decreasing oxidative stress and apoptosis, which was comparable to the results of positive control of N-acetylcysteine (Nac). In conclusion, this study not only established a solid foundation for future study on therapeutic potential of Bv, but also proposed a promising treatment approach for enhancing the success rate of flap transplants and other ischemic-related tissue repair.

The repair of diabetic wounds remains challenging, primarily due to the high-glucose-derived immune inhibition which often leads to the excessive inflammatory response, impaired angiogenesis, and heightened susceptibility to infection. However, the means to reduce the immunosuppression and regulate the conversion of M2 phenotype macrophages under a high-glucose microenvironment using advanced biomaterials for diabetic wounds are not yet fully understood. Herein, we report two-dimensional carbide (MXene)-M2 macrophage exosome (Exo) nanohybrids (FM-Exo) for promoting diabetic wound repair by overcoming the high-glucose-derived immune inhibition. FM-Exo showed the sustained release of M2 macrophage-derived exosomes (M2-Exo) up to 7 days and exhibited broad-spectrum antibacterial activity. In the high-glucose microenvironment, relative to the single Exo, FM-Exo could significantly induce the optimized M2a/M2c polarization ratio of macrophages by activating the PI3K/Akt signaling pathway, promoting the proliferation, migration of fibroblasts, and angiogenic ability of endothelial cells. In the diabetic full-thickness wound model, FM-Exo effectively regulated the polarization status of macrophages and promoted their transition to the M2 phenotype, thereby inhibiting inflammation, promoting angiogenesis through VEGF secretion, and improving proper collagen deposition. As a result, the healing process was accelerated, leading to a better healing outcome with reduced scarring. Therefore, this study introduced a promising approach to address diabetic wounds by developing bioactive nanomaterials to regulate immune inhibition in a high-glucose environment.

Avascular necrosis frequently occurs as a complication following surgery involving the distal perforator flap. Dihydrocapsaicin (DHC) can protect tissue from ischemia-reperfusion (I/R) injury, but its specific role in multizone perforator flaps remains unclear. In this study, the prospective target of DHC in the context of I/R injury was predicted using network pharmacology analysis. Flap viability was determined through survival area analysis, laser Doppler blood flow, angiograms, and histological examination. The expressions of angiogenesis, apoptosis, NLR family pyrin domain containing 3 (NLRP3) inflammasome, oxidative stress, and molecules related to cyclic guanosine monophosphate (GMP)-adenosine monophosphate synthase (cGAS)-interferon gene stimulant (STING) pathway were assessed using western blotting, immunofluorescence, TUNEL staining, and dihydroethidium (DHE) staining. Our finding revealed that DHC promoted the perforator flap survival, which involves the cGAS-STING pathway, oxidative stress, NLRP3 inflammasome, apoptosis, and angiogenesis. DHC induced oxidative stress resistance and suppressed the NLRP3 inflammasome, preventing apoptosis in vascular endothelial cells. Through regulation of STING pathway, DHC controlled oxidative stress in endothelial cells and NLRP3 levels in ischemic flaps. However, activation of the cGAS-STING pathway led to the accumulation of reactive oxygen species (ROS) and NLRP3 inflammasome, thereby diminishing the protective role of DHC. DHC enhanced the survival of multidomain perforator flaps by suppressing the cGAS-STING pathway, oxidative stress, and the formation of NLRP3 inflammasome. These findings unveil a potentially novel mechanism with clinical significance for promoting the survival of multidomain perforator flaps.

Due to their simplicity and reliability, random-pattern skin flaps are commonly utilized in surgical reconstruction to repair cutaneous wounds. However, the post-operative necrosis frequently happens because of the ischemia and high-level of oxidative stress of random skin flaps, which can severely affect the healing outcomes. Earlier evidence has shown promising effect of Nuciferine (NF) on preventing hydrogen peroxide (H2O2)-induced fibroblast senescence and ischemic injury, however, whether it can function on promoting ischemic flap survival remains unknown. In this work, using network pharmacology analysis, it was possible to anticipate the prospective targets of NF in the context of ischemia. The results revealed that NF treatment minimized H2O2-induced cellular dysfunction of human umbilical vein endothelial cells (HUVECs), and also improved flap survival through strengthening angiogenesis and alleviating oxidative stress, inflammation and apoptosis in vivo. These outcomes should be attributed to TFEB-mediated enhancement of autophagy-lysosomal degradation via the AMPK-mTOR signaling pathway, whilst the restriction of autophagy stimulation with 3MA effectively diminished the above advantages of NF treatment. The increased nuclear translocation of TFEB not only restored lysosome function, but also promoted autophagosome-lysosome fusion, eventually restoring the inhibited autophagic flux and filling the high energy levels. The outcomes of our research can provide potent proof for the application of NF in the therapy of vascular insufficiency associated disorders, including random flaps.

The tissue reconstruction of diabetic wounds mainly depends on the proliferation and remodelling of cutaneous cells around wounds and the transplantation of random skin flaps, however, the proliferation of cells or survival of skin flaps are difficult due to the severe inflammation and other problems caused by diabetes. The stem cell-derived exosomes loaded with miRNA can be an effective therapeutic strategy for promoting diabetic wound healing. Therefore, in this study, the engineered exosomes derived from miR-132-overexpressing adipose stem cells (miR-132-exo) was obtained for promoting the healing of diabetic wounds and skin flaps. In vitro, the miR-132-exo promoted the proliferation and migration of human umbilical vein endothelial cells (HUVECs). In vivo, streptozotocin (STZ) induced diabetic mice were used to create full-thickness skin wounds and random skin flaps to further investigate the healing effect of miR-132-exo. The results showed miR-132-exo evidently enhanced the survival of skin flaps and promote diabetic wound healing, through reducing local inflammation, promoting angiogenesis and stimulating M2-macrophages polarization mediated by NF-κB signaling pathway. These novel findings demonstrated that engineered miR-132-exo can be a potent therapeutic for treating diabetic wounds and inflammatory-related disease.

BACKGROUND In this study we prepared liposome microbubbles loading resveratrol (LMLR) and evaluated its therapeutic effect on injury of gastrocnemius muscle in rats. MATERIAL AND METHODS LMLR was prepared and characterized by particle size, potential, and microscopy, and a rat model of acute blunt injury of gastrocnemius muscle was established. After treatments with resveratrol or LMLR, the therapeutic effects were evaluated by hematoxylin-eosin (HE) staining. The expression of MHCIIB and vimentin in mRNA level was measured by real-time PCR. The expression of desmin and collagen I protein was assessed by immunohistochemistry. RESULTS LMLR showed regular cycle shape in a size of ~1000 nm. LMLR was negatively charged (-30 mV). The in vitro release of LMLR was close to 80% at 10 h and 90% at 48 h. Acute gastrocnemius muscle injury was established in rats and tissue recovery was observed after LMLR treatment as evidenced by HE staining, decreased expression of MHCIIB, and increased expression of vimentin. Moreover, LMLR treatment obviously facilitated desmin expression and reduced collagen I expression. CONCLUSIONS LMLR is effective in treating acute blunt injury of gastrocnemius muscle in rats.

This publication has been retracted by the Editor due to concerns regarding the originality of the figure images.Reference:Yongzeng Feng, Zili He, Cong Mao, Xiaolong Shui, Leyi Cai. Therapeutic Effects of Resveratrol Liposome on Muscle Injury in Rats. Med Sci Monit, 2019; 25:2377-2385. DOI: 10.12659/MSM.913409.

[This corrects the article DOI: 10.7150/thno.41839.].

Among metabolic and systemic bone diseases, osteoporosis is known as one of the most progressive disease characterized by bone microstructural deterioration and bone mass reduction. Calcitriol (Cal) is widely accepted as a fat-soluble small molecule drug with reported anti-osteoporotic activity. However, delivery systems capable of local sustained release of small molecule drugs remain a significant challenge. Herein, based on poly(D, L-lactide)-poly(ethylene glycol)-poly(D, L-lactide) (PDLLA-PEG-PDLLA) hydrogels, we developed a thermosensitive and multifunctional sustainable delivery system by doubly integrating with polydopamine modified nano-hydroxyapatite (HA-D) and calcitriol-loaded amino-terminated poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PCL-PEG-NH2) micelles to realize the long-term delivery of small molecule drugs. The sustained release of Cal from the system was associate with triple controlled release effects including the protective screen of the hydrogels over micelles, the reservoir effect of the HA nanoparticles for Cal, and the encapsulation of Cal in micelles. In vitro, results from the present study demonstrated that sustainable delivery system effectively activated osteogenesis, proliferation and migration in these bone mesenchymal stromal cells of ovariectomized rats (OVX-rBMSCs). In vivo, the composite Cal-loaded system was verified to promote bone regeneration in the critical-size femoral epicondyle bone defect model. Meanwhile, little cytotoxicity and appropriate degradation rate of the composite Cal delivery system were revealed. Thus, incorporating Cal into a multifunctional delivery system to perform a long-acting drug delivery in an injectable hydrogel form is a promising therapeutic to improve anti-osteoporotic ability and promote bone regeneration of osteoporosis. (C) 2020 Elsevier Ltd. All rights reserved.

Diabetic wound healing still faces great challenges due to the excessive inflammation, easy infection, and impaired angiogenesis in wound beds. The immunoregulation of macrophages polarization toward M2 phenotype that facilitates the transition from inflammation to proliferation phase has been proved to be an effective way to improve diabetic wound healing. Herein, an M2 phenotype-enabled anti-inflammatory, antioxidant, and antibacterial conductive hydrogel scaffolds (GDFE) for producing rapid angiogenesis and diabetic wound repair are reported. The GDFE scaffolds are fabricated facilely through the dynamic crosslinking between polypeptide and polydopamine and graphene oxide. The GDFE scaffolds possess thermosensitivity, self-healing behavior, injectability, broad-spectrum antibacterial activity, antioxidant and anti-inflammatory ability, and electronic conductivity. GDFE effectively activates the polarization of macrophages toward M2 phenotype and significantly promotes the proliferation of dermal fibroblasts, the migration, and in vitro angiogenesis of endothelial cells through paracrine mechanisms. The in vivo results from a full-thickness diabetic wound model demonstrate that GDFE can rapidly promote the diabetic wound repair and skin regeneration, through fast anti-inflammation and angiogenesis and M2 macrophage polarization. This study provides highly efficient strategy for treating diabetic wound repair through designing the M2 polarization-enabled anti-inflammatory, antioxidant, and antibacterial bioactive materials.

[This corrects the article DOI: 10.7150/thno.29766.].

Random skin flaps have been widely applied in reconstructive and plastic surgery; however, necrosis usually happens due to insufficient blood supply in the ischemic area of flaps. Curcumin (CUR) is a primary bioactive compound of turmeric (Curcuma longa, L.), which has been proven to be effective on anticancer, decreasing oxidative stress and apoptosis through activating autophagy, and promoting angiogenesis in ischemic tissue. Therefore, the potential therapeutic effect of CUR on promoting survival of ischemic random skin flaps and its underlying mechanism associated with autophagy were investigated. After establishment of dorsal random skin flaps, sixty mice were randomly divided into three groups: Control, CUR or CUR+3-methyladenine (3-MA, an autophagy inhibitor). The results showed that CUR increased the viability area and blood flow as well as relieved the edema of skin flaps through promoting angiogenesis, decreasing oxidative stress, and inhibiting apoptosis of the ischemic area. Further study confirmed that CUR activated autophagy in the random skin flaps, and 3-MA effectively reversed the effect on viability, neovascularization, oxidative stress and apoptosis, suggesting autophagy played a vital role in these CUR's protective effect on random skin flaps. Moreover, this CUR-induced autophagy should be mediated through downregulating the PI3K/AKT/mTOR signaling pathway. Together with secondary response of increased angiogenesis, reduced oxidative stress and apoptosis, CUR effectively improved survival of random skin flaps in vivo. To sum up, our research showed the great potential of CUR using as a promising flap protective therapy for random skin flap survival and regeneration.

Wound therapy remains a clinical challenge due to the complexity of healing pathology and high demand of achieving functional and aesthetically satisfactory scars. Newly formed blood vessels are essential for tissue repair since they can support cells at the wound site with nutrition and oxygen. In this study, we investigated the effects of Asperosaponin VI (ASA VI) isolated from a traditional Chinese medicine, the root of Dipsacus asper Wall, in promoting angiogenesis, as well as its function in wound therapeutics. Treatment of human umbilical vein endothelial cells (HUVECs) with ASA VI (20–80 μg/mL) dose-dependently promoted the proliferation, migration and enhanced their angiogenic ability in vitro, which were associated with the up-regulated HIF-1α/VEGF signaling. Full-thickness cutaneous wound model rats were injected with ASA VI (20 mg·kg−1·d−1, iv) for 21 d. Administration of ASA VI significantly promoted the cutaneous wound healing, and more blood vessels were observed in the regenerated tissue. Due to rapid vascularization, the cellular proliferation status, granulation tissue formation, collagen matrix deposition and remodeling processes were all accelerated, resulting in efficient wound healing. In summary, ASA VI promotes angiogenesis of HUVECs in vitro via up-regulating the HIF-1α/VEGF pathway, and efficiently enhances the vascularization in regenerated tissue and facilitates wound healing in vivo. The results reveal that ASA VI is a potential therapeutic for vessel injury-related wounds.