Comparing collagenase and silver sulfadiazine in deep second-degree burn treatment.

The indications for collagenase ointment (CO) and its efficacy are not clearly established in the treatment of second-degree burn wounds. To evaluate the efficacy of CO versus silver sulfadiazine ointment (SSD) in the treatment of second-degree burn wounds. A total of 170 eligible patients with deep second-degree burns, aged 18-65 years, with injuries occurring within 48-96 h, and having a total wound area of less than 30% of the total body surface area were included from 5 centers in China. The primary outcome was the wound healing time, and the secondary outcomes were the clearance time of wound necrotic tissues, wound healing rate, and wound inflammation. The study included 85 patients in SSD group and 84 in CO group in the modified intention-to-treat (mITT) population. The median time of wound healing was comparable in both groups (10 days vs. 10.5 days P = 0.16). The time for wound necrotic tissue removal was significantly shortened by CO compared with SSD (5 vs. 10 days P < 0.01). Wound inflammation, pain, wound healing rate, and scar were compared with SSD (all P-values > 0.05). No adverse events, such as infection or allergic reactions to the drugs and materials used, were reported. Both CO and SSD could heal the burn wounds at 10 days of treatment. However, CO significantly shortened the time of wound necrotic tissue removal by 5 days. Trial Registration: ChiCTR2100046971.

Exploring causal correlations between inflammatory cytokines and Ménière's disease: a Mendelian randomization.

Objectives: Previous studies have highlighted associations between certain inflammatory cytokines and Ménière's Disease (MD), such as interleukin (IL) -13 and IL-1ß. This Mendelian randomization aims to comprehensively evaluate the causal relationships between 91 inflammatory cytokines and MD. Methods: A comprehensive two-sample Mendelian randomization (MR) analysis was conducted to determine the causal association between inflammatory cytokines and MD. Utilizing publicly accessible genetic datasets, we explored causal links between 91 inflammatory cytokines and MD risk. Comprehensive sensitivity analyses were employed to assess the robustness, heterogeneity, and presence of horizontal pleiotropy in our findings. Results: Our findings indicate that MD causally influences the levels of two cytokine types: IL-10 (P=0.048, OR=0.945, 95%CI =0.894~1.000) and Neurotrophin-3 (P=0.045, OR=0954, 95%CI =0.910~0.999). Furthermore, three cytokines exhibited significant causal effects on MD: CD40L receptor (P=0.008, OR=0.865, 95%CI =0.777-0.963), Delta and Notch-like epidermal growth factor-related receptor (DNER) (P=0.010, OR=1.216, 95%CI =1.048-1.412), and STAM binding protein (P=0.044, OR=0.776, 95%CI =0.606-0.993). Conclusion: This study suggests that the CD40L receptor, DNER, and STAM binding protein could potentially serve as upstream determinants of MD. Furthermore, our results imply that when MD is regarded as the exposure variable in MR analysis, it may causally correlate with elevated levels of IL-10 and Neurotrophin-3. Using these cytokines for MD diagnosis or as potential therapeutic targets holds great clinical significance.

Pretreatment with platelet-rich plasma protects against ischemia-reperfusion induced flap injury by deactivating the JAK/STAT pathway in mice.

BACKGROUND: Ischemia-reperfusion (I/R) injury is a major cause of surgical skin flap compromise and organ dysfunction. Platelet-rich plasma (PRP) is an autologous product rich in growth factors, with tissue regenerative potential. PRP has shown promise in multiple I/R-induced tissue injuries, but its effects on skin flap injury remain unexplored. METHODS: We evaluated the effects of PRP on I/R-injured skin flaps, optimal timing of PRP administration, and the involved mechanisms. RESULTS: PRP protected against I/R-induced skin flap injury by improving flap survival, promoting blood perfusion and angiogenesis, suppressing oxidative stress and inflammatory response, and reducing apoptosis, at least partly via deactivating Janus kinase (JAK)-signal transducers and activators of transcription (STAT) signalling pathway. PRP given before ischemia displayed overall advantages over that given before reperfusion or during reperfusion. In addition, PRP pretreatment had a stronger ability to reverse I/R-induced JAK/STAT activation and apoptosis than AG490, a specific inhibitor of JAK/STAT signalling. CONCLUSIONS: This study firstly demonstrates the protective role of PRP against I/R-injured skin flaps through negative regulation of JAK/STAT activation, with PRP pretreatment showing optimal therapeutic effects.

Laparoscopic harvest and free transplantation of great omentum flap for extensive tissue defects in complex wounds.

Introduction: The repair of extensive tissue defects remains a challenge, although great progress has been made in reconstructive surgery. The transplantation of a single huge flap or several flaps in combination will inevitably result in donor-site morbidity. Here we report our experience in the repair of these wounds with laparoscopically harvested great omentum flaps. Methods: Twelve patients with extensive tissue defects caused by deep burn injury, avulsion injury, and open fracture underwent free omental flap transplantation and split-thickness skin grafting. The patient demographics, wound characteristics, and complications postsurgical operation were recorded. Prior to omentum flap transplantation, these patients underwent debridement, vacuum sealing drainage treatment, and/or fixation of fractures. All omentum flaps harvested using laparoscopic technique were anastomosed to recipient vessels, and split-thickness skin grafting was performed 14 days after omental flap transplantation. Results: The mean defect size was 471 cm2 and the mean omental flap size was 751.1 cm2. Among all 12 cases, the omental flaps survived well except for distal partial necrosis in one case. Skin grafting was also achieved in all cases, and all patients achieved complete wound coverage. All donor sites achieved primary healing without major complications. The mean follow-up time was 30 months with satisfactory appearance and functional outcome. Conclusion: For the reconstruction of extensive tissue defects in complex wounds, the free transfer of an omental flap may be an ideal option because of its well-vascularized and pliable tissue with reliable vascular anatomy, as well as minimized donor-site morbidity.

The emerging progress on wound dressings and their application in clinic wound management.

Background: In addition to its barrier function, the skin plays a crucial role in maintaining the stability of the body's internal environment and normal physiological functions. When the skin is damaged, it is important to select proper dressings as temporary barriers to cover the wound, which can exert significant effects on defence against microbial infection, maintaining normal tissue/cell functions, and coordinating the process of wound repair and regeneration. It now forms an important approach in clinic practice to facilitate wound repair. Search strategies: We conducted a comprehensive literature search using online databases including PubMed, Web of Science, MEDLINE, ScienceDirect, Wiley Online Library, CNKI, and Wanfang Data. In addition, information was obtained from local and foreign books on biomaterials science and traumatology. Results: This review focuses on the efficacy and principles of functional dressings for anti-bacteria, anti-infection, anti-inflammation, anti-oxidation, hemostasis, and wound healing facilitation; and analyses the research progress of dressings carrying living cells such as fibroblasts, keratinocytes, skin appendage cells, and stem cells from different origins. We also summarize the recent advances in intelligent wound dressings with respect to real-time monitoring, automatic drug delivery, and precise adjustment according to the actual wound microenvironment. In addition, this review explores and compares the characteristics, advantages and disadvantages, mechanisms of actions, and application scopes of dressings made from different materials. Conclusion: The real-time and dynamic acquisition and analysis of wound conditions are crucial for wound management and prognostic evaluation. Therefore, the development of modern dressings that integrate multiple functions, have high similarity to the skin, and are highly intelligent will be the focus of future research, which could drive efficient wound management and personalized medicine, and ultimately facilitate the translation of health monitoring into clinical practice.

Autologous Scar-Related Tissue Combined with Skin Grafting for Reconstructing Large Area Burn Scar.

BACKGROUND: This study introduced a novel method to reconstruct large areas of scarring caused by burns via combining autologous scar-related tissue with spit-thickness skin grafting (ASTCS). METHODS: 25 patients underwent reconstruction after scar resection surgeries around the joints were analyzed between Jan 2012 and Jan 2018. Patient demographics and clinical parameters were collected, autologous scar-related tissue was modified to meshed structure, and the split-thickness skin was acquired from the scalp. The scar was resected and punched by a meshing machine with a thickness of 0.3-0.5 mm at a ratio of 1:1. The secondary wounds were covered by the epidermis from a donor site. The surgical areas were bandaged for 7-10 days before the first dressing change. RESULTS: 25 patients (mean [SD] age, 26.4 [18.8] years; 16 [64%] men) underwent wounds reconstructive operations due to scar resection were reviewed. Wound location of 9 (22%), 8 (19.5%), 9 (22%), 7 (17.1%) and 8 (19.5%) cases were reconstructed in axillary, hand and wrist, popliteal fossa, elbow and neck, respectively. 39 sites of transplanted tissues survived well, and 2 sites were cured after two weeks of dressing changes. Except the analysis of injury causes, nutritional status, wound area and hospital days, patients with scar deformities in joint areas achieved satisfactory function by assessing the Vancouver Burn Skin Score and the Barthel Index Scale Scores after 12-month follow-up. CONCLUSIONS: Combining autologous scar-related tissue with skin grafting provided a novel method for treating large areas of burn scars with better functional outcomes.

Antibacterial activity of ZnO quantum dots and its protective effects of chicks infected withSalmonella pullorum.

In light of emerging antibiotic resistance, synthesis of active, environmental friendly antimicrobial alternatives becomes increasingly necessary. In this study, ZnO quantum dots (ZnO QDs) were developed by the sol-gel method and characterized. The antibacterial activities of ZnO QDs againstEscherichia coli(E. coli),Staphylococcus aureus(S. aureus) andSalmonella Pullorum(S. Pullorum) were systematically investigated. Moreover, the protective effects of ZnO QDs on Salmonella-caused pullorosis in chicks were also explored. The results indicated that the size range of ZnO QDs was 3-6 nm. Antibacterial results showed that ZnO QDs treatment inhibited the growth ofE. coli,S. aureus, andS. Pullorumin the rate of 87.06 ± 0.98%, 94.75 ± 2.28%, and 85.55 ± 1.15%, respectively. Its excellent antibacterial property was manifested with the minimum inhibitory concentration of 0.7812, 0.0976, and 0.1953 mg ml-1, which may be attributed to the production of reactive oxygen species, the dissolution of Zn2+ions, and the loss of cell integrity. Furthermore, in thein vivotest, the ZnO QDs effectively reduced the mortality of chicks infected withS. Pullorumvia regulating the balance of the intestinal flora, protecting liver and intestine, and modulating the balance of antioxidation systems. This study reveals that ZnO QDs exerts remarkably antibacterial activityin vitroand anti-pullorosis effect in chicks.

Extracellular Vesicles From Adipose Tissue-Derived Stem Cells Affect Notch-miR148a-3p Axis to Regulate Polarization of Macrophages and Alleviate Sepsis in Mice.

Extracellular vesicles (EVs) from adipose tissue-derived stem cells have been reported to attenuate lipopolysaccharide (LPS) induced inflammation and sepsis while the specific mechanism is unclear. This study explored the underlying molecular mechanisms of EVs from adipose tissue-derived stem cells in reducing inflammation. LPS- induced macrophage models and mice model were established to mimic inflammation in vitro and in vivo. EVs were extracted from adipose tissue-derived stem cells and identified. It was found that proinflammatory cytokines, including IL-1ß, IL-6, and TNF-α, substantially decreased after EVs were applied to LPS-stimulated macrophages and mice, and thus, LPS induced M1 polarization was inhibited and sepsis was strongly alleviated. In the LPS induced macrophages, the expression of Notch signaling molecules and the activation of the NF-κB pathway were substantially decreased after the administration of EVs. Then, RBP-J-/- mice and macrophages were used. It was found that the miR-148a-3p level was significantly lower in the RBP-J-/- macrophages than in the wildtype macrophages. In the LPS induced macrophages, the increasing of miR-148a-3p was milder in the RBP-J-/- macrophages than in the wild type macrophages. Then, miR-148a-3p was overexpressed in macrophages and mice, and we found that the expression of proinflammatory cytokines was increased both in vivo and in vitro. The protective effect of EVs in LPS induced sepsis was diminished by the overexpression of miR-148a-3p. In conclusion, we proved that EVs could attenuate inflammation and further protect organ function by regulating the Notch-miR148a-3p signaling axis and then decreasing macrophage polarization to M1.

Notch signal deficiency alleviates hypertrophic scar formation after wound healing through the inhibition of inflammation.

Pathological scar is a common complication after wound healing. One of the most important factors that affects scar formation is inflammation. During this process, macrophages play a critical role in the wound healing process, as well as in scar formation. Notch signaling is reported to participate in inflammation and fibrosis; however, whether it affects scar formation is still unclear. In this study, RBP-J knockout mice, in which Notch signaling was down-regulated, and control mice were used, and a skin incision model was established. Sirius red staining and Masson staining suggested that RBP-J knockout could significantly reduce collagen sedimentation after wound healing. Western blot analysis and RT-PCR also confirmed the results. During wound healing, the expression of inflammatory cytokines and macrophage infiltration were decreased in RBP-J knockout mice. In vitro, it was also verified that RBP-J deficiency in macrophages effectively suppressed the expression of inflammatory cytokines and chemotaxis of macrophages after LPS stimulation. In conclusion, blocking Notch signaling in macrophages effectively alleviated scar formation by suppressing the inflammatory response and collagen sedimentation.

Testin regulates the blood-testis barrier via disturbing occludin/ZO-1 association and actin organization.

The blood-testis barrier (BTB) separates the seminiferous epithelium into the apical and basal compartments. The BTB has to operate timely and accurately to ensure the correct migration of germ cells, meanwhile maintaining the immunological barrier. Testin was first characterized from primary Sertoli cells, it is a secretory protein and a sensitive biomarker to monitor junctions between Sertoli and germ cells. Till now, the functions of testin on BTB dynamics and the involving mechanisms are unknown. Herein, testin acts as a regulatory protein on BTB integrity. In vitro testin knockdown by RNAi caused significant damage to the Sertoli cell barrier with no apparent changes in the protein levels of several major tight junction (TJ), adhesion junction, and gap junction proteins. Also, testin RNAi caused the diffusion of two TJ structural proteins, occludin and ZO-1, diffusing away from the Sertoli cell surface into the cytoplasm. Association and colocalization between ZO-1 and occludin were decreased after testin RNAi, examined by Co-IP and coimmunofluorescent staining, respectively. Furthermore, testin RNAi induced a dramatic disruption on the arrangement of actin filament bundles and a reduced F-actin/G-actin ratio. The actin regulatory protein ARP3 appeared at the Sertoli cell interface after testin RNAi without its protein level change, whereas overexpressing testin in Sertoli cells showed no effect on TJ barrier integrity. The above findings suggest that besides as a monitor for Sertoli-germ cell junction integrity, testin is also an essential molecule to maintain Sertoli-Sertoli junctions.

Activation of Brainstem Neurons During Mesencephalic Locomotor Region-Evoked Locomotion in the Cat.

The distribution of locomotor-activated neurons in the brainstem of the cat was studied by c-Fos immunohistochemistry in combination with antibody-based cellular phenotyping following electrical stimulation of the mesencephalic locomotor region (MLR) - the anatomical constituents of which remain debated today, primarily between the cuneiform (CnF) and the pedunculopontine tegmental nuclei (PPT). Effective MLR sites were co-extensive with the CnF nucleus. Animals subject to the locomotor task showed abundant Fos labeling in the CnF, parabrachial nuclei of the subcuneiform region, periaqueductal gray, locus ceruleus (LC)/subceruleus (SubC), Kölliker-Fuse, magnocellular and lateral tegmental fields, raphe, and the parapyramidal region. Labeled neurons were more abundant on the side of stimulation. In some animals, Fos-labeled cells were also observed in the ventral tegmental area, medial and intermediate vestibular nuclei, dorsal motor nucleus of the vagus, n. tractus solitarii, and retrofacial nucleus in the ventrolateral medulla. Many neurons in the reticular formation were innervated by serotonergic fibers. Numerous locomotor-activated neurons in the parabrachial nuclei and LC/SubC/Kölliker-Fuse were noradrenergic. Few cholinergic neurons within the PPT stained for Fos. In the medulla, serotonergic neurons within the parapyramidal region and the nucleus raphe magnus were positive for Fos. Control animals, not subject to locomotion, showed few Fos-labeled neurons in these areas. The current study provides positive evidence for a role for the CnF in the initiation of locomotion while providing little evidence for the participation of the PPT. The results also show that MLR-evoked locomotion involves the parallel activation of reticular and monoaminergic neurons in the pons/medulla, and provides the anatomical and functional basis for spinal monoamine release during evoked locomotion. Lastly, the results indicate that vestibular, cardiovascular, and respiratory centers are centrally activated during MLR-evoked locomotion. Altogether, the results show a complex pattern of neuromodulatory influences of brainstem neurons by electrical activation of the MLR.

MicroRNA-494 targets PTEN and suppresses PI3K/AKT pathway to alleviate hypertrophic scar formation.

Hypertrophic scar is a common complication after skin injury. MicroRNAs have been reported related to hypertrophic scar through posttranscriptional control of genes. Hypertrophic scar-derived fibroblast model and mice incision model were used to see the expression of microRNA-494 and whether the level changes of microRNA-494 could affect scar formation. It was found that in hypertrophic scar, the expression of microRNA-494 decreased. However, after over-express microRNA-494 in fibroblasts, the levels of scar related molecules such as Col I, Col III increased. And when suppress the level of microRNA-494 in fibroblasts, the levels of collagen decreased. Moreover, the up-regulation of microRNA-494 led to decreased apoptosis of fibroblasts while the down-regulation of it led to increased apoptosis. Further, it was found that PTEN was one of the downstream targets of microRNA-494. The up-regulation of PTEN led to inactivation of PI3K/AKT pathway and the decreased expression of collagens. In conclusion, we confirmed that microRNA-494 could be a key regulator to suppress hypertrophic scar formation. The suppression of microRNA-494 could eliminate its inhibition effect to PTEN and finally decrease the expression of collagen and inhibit hypertrophic scar formation.

Linagliptin inhibits high glucose-induced transdifferentiation of hypertrophic scar-derived fibroblasts to myofibroblasts via IGF/Akt/mTOR signalling pathway.

Hypertrophic scar (HS) is a fibroproliferative disease after serious burns; the underlying mechanism remains unknown. The study was performed to clarify the effect of high glucose (HG) on HS. The expression of Col1, Col3 and α-SMA was upregulated in HS-derived fibroblasts (HSF) exposed to HG (20 and 30 mmol/L), and HG activated the phosphorylated protein expression of IGF/Akt/mTOR signalling pathway in HSF. Dpp4, a marker targeted the treatment of diabetes mellitus, was overexpressed in HG-induced HSF. Linagliptin, a Dpp4 inhibitor, played the antifibrotic role in HSF exposed to HG, the levels of Col1, Col3 and α-SMA were significantly downregulated, and the cell proliferation and migration were also inhibited. Furthermore, linagliptin alleviated the phosphorylated protein expression of IGF/Akt/mTOR signalling pathway. Moreover, the mTOR inhibitor (rapamycin) mimicked the effect of linagliptin on the collagen and α-SMA that means linagliptin may inhibit HG-induced transdifferentiation of HSF to myofibroblasts via IGF/Akt/mTOR signalling pathway.

A Randomized, Placebo-Controlled, Double-Blind, Prospective Clinical Trial of Botulinum Toxin Type A in Prevention of Hypertrophic Scar Development in Median Sternotomy Wound.

BACKGROUND: Linear hypertrophic scar is a common surgical problem that can be difficult to manage, especially for the median sternotomy scar. Botulinum toxin type A (BTA) is widely used in cosmetic surgery and has been shown to improve scar quality recently. The aim of this study was to evaluate the efficacy of BTA injected in the early postoperative of median sternotomy on preventing scar formation. METHODS: In this prospective randomized controlled trial, 19 consecutive patients who underwent median sternotomy were enrolled. The median sternotomy wound in each patient was divided into the upper half and the lower half. Both halves of the wound were randomized to receive the treatment with either BTA or normal saline. At 6-month follow-up, scars were assessed using the Vancouver Scar Scale, scar widths were measured, and patients were asked to evaluate their overall satisfaction. RESULTS: Seventeen patients with median sternotomy wounds completed the entire study. At 6-month follow-up, the mean Vancouver Scar Scale score for the BTA-treated group was 3.44 ± 1.68 and for the normal saline control group was 6.29 ± 2.39, and there was a statistically significant difference between the two groups (P < 0.05). There were also significant improvements in scar width and patient satisfaction for the BTA-treated halves of the wounds (P < 0.05). CONCLUSIONS: The study demonstrates that early postoperative BTA injection can decrease scar formation and reduce scar width in median sternotomy wounds, and the overall appearance is more satisfactory. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Monoamine Release in the Cat Lumbar Spinal Cord during Fictive Locomotion Evoked by the Mesencephalic Locomotor Region.

Spinal cord neurons active during locomotion are innervated by descending axons that release the monoamines serotonin (5-HT) and norepinephrine (NE) and these neurons express monoaminergic receptor subtypes implicated in the control of locomotion. The timing, level and spinal locations of release of these two substances during centrally-generated locomotor activity should therefore be critical to this control. These variables were measured in real time by fast-cyclic voltammetry in the decerebrate cat's lumbar spinal cord during fictive locomotion, which was evoked by electrical stimulation of the mesencephalic locomotor region (MLR) and registered as integrated activity in bilateral peripheral nerves to hindlimb muscles. Monoamine release was observed in dorsal horn (DH), intermediate zone/ventral horn (IZ/VH) and adjacent white matter (WM) during evoked locomotion. Extracellular peak levels (all sites) increased above baseline by 138 ± 232.5 nM and 35.6 ± 94.4 nM (mean ± SD) for NE and 5-HT, respectively. For both substances, release usually began prior to the onset of locomotion typically earliest in the IZ/VH and peaks were positively correlated with net activity in peripheral nerves. Monoamine levels gradually returned to baseline levels or below at the end of stimulation in most trials. Monoamine oxidase and uptake inhibitors increased the release magnitude, time-to-peak (TTP) and decline-to-baseline. These results demonstrate that spinal monoamine release is modulated on a timescale of seconds, in tandem with centrally-generated locomotion and indicate that MLR-evoked locomotor activity involves concurrent activation of descending monoaminergic and reticulospinal pathways. These gradual changes in space and time of monoamine concentrations high enough to strongly activate various receptors subtypes on locomotor activated neurons further suggest that during MLR-evoked locomotion, monoamine action is, in part, mediated by extrasynaptic neurotransmission in the spinal cord.

PKCζ as a promising therapeutic target for TNFα-induced inflammatory disorders in chronic cutaneous wounds.

Protein kinase Cζ (PKCζ) is a member of the atypical protein kinase C family. Its roles in macrophages or skin-resident keratinocytes have not been fully evaluated. In this study, we provide evidence that PKCζ mediates lipopolysaccharide (LPS)-induced tumor necrosis factor α (TNFα) gene expression in the mouse macrophage cell line, RAW264.7. TNFα has been proven to be one of the main culprits of chronic wounds and impaired acute wounds, which are characterized by excessive inflammation, enhanced proteolysis and reduced matrix deposition. Among the multiple effects of TNFα on keratinocytes, the induction of chemokines which are indispensable factors involved in the massive infiltration of various inflammatory cells into skin lesions serves as a crucial mechanism. In the present study, we found that PKCζ inhibitor or its specific siRNA inhibited the TNFα-induced upregulation in the levels of the chemokines, interleukin (IL)-8, monocyte chemotactic protein-1 (MCP-1) and intercellular cell adhesion molecule-1 (ICAM-1) in HaCaT keratinocytes. Moreover, under a disrupted inflammatory environment, activated keratinocytes can synthesize large amounts of matrix metalloproteinases (MMP), which has a negative effect on tissue remodeling. We discovered that TNFα promoted the expression of MMP9 in a PKCζ-dependent manner. Further experiments revealed that nuclear factor-κB (NF-κB) was a key downstream molecule of PKCζ. In addition, as shown in vitro, PKCζ was not involved in the TNFα-induced decrease in HaCaT cell migration and proliferation. In vivo experiments demonstrated that TNFα-induced wound closure impairment and inflammatory disorders were significantly attenuated in the PKCζ inhibitor group. On the whole, our findings suggest that PKCζ is a crucial regulator in LPS- or TNFα-induced inflammatory responses in RAW264.7 cells and HaCaT keratinocytes, and that PKCζ/NF-κB signaling may be a potential target for interventional therapy for TNFα-induced skin inflammatory injury.

Efficient generation of functional Schwann cells from adipose-derived stem cells in defined conditions.

Schwann cells (SCs) are hitherto regarded as the most promising candidates for viable cell-based therapy to peripheral nervous system (PNS) injuries or degenerative diseases. However, the extreme drawbacks of transplanting autologous SCs for clinical applications still represent a significant bottleneck in neural regenerative medicine, mainly owing to the need of sacrificing a functional nerve to generate autologous SCs and the nature of slow expansion of the SCs. Thus, it is of great importance to establish an alternative cell system for the generation of sufficient SCs. Here, we demonstrated that adipose-derived stem cells (ADSCs) of rat robustly give rise to morphological, phenotypic and functional SCs using an optimized protocol. After undergoing a 3-week in vitro differentiation, almost all of treated ADSCs exhibited spindle shaped morphology similar to genuine SCs and expressed SC markers GFAP and S100. Most importantly, apart from acquisition of SC antigenic and biochemical features, the ADSC-derived SCs were functionally identical to native SCs as they possess a potential ability to form myelin, and secret nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and glia-derived neurotrophic factor (GDNF). The current study may provide an ideal strategy for harvesting sufficient SCs for cell-based treatment of various peripheral nerve injuries or disorders.

Peroxisome proliferator-activated receptor-γ agonist troglitazone suppresses transforming growth factor-ß1 signalling through miR-92b upregulation-inhibited Axl expression in human keloid fibroblasts in vitro.

Keloid, a skin benign tumor, is characterized by overgrowth of fibroblasts and the excessive deposition of extracellular matrix in wounded skin. Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist was recently evaluated to inhibit fibrosis. This study explored the underlying mechanisms. Fibroblasts isolated from 25 keloid patients (KFs) and fibroblasts isolated from healthy controls (NSFBs) were also subjected to treatment with PPAR-γ agonist troglitazone and antagonist GW9662 or for transfection with miR-92 mimics or inhibitor, Axl siRNA, and miR-92b or Axl promoter constructs, as well as being subjected to qRT-PCR, ELISA, Western blot, protein array, luciferase, and ChIP assays. The data demonstrated that TGF-ß1 and Axl proteins were significantly elevated in samples from keloid patients, while troglitazone treatment significantly reduced levels of TGF-ß1 and Axl mRNA and proteins in KFs. Moreover, knockdown of Axl expression reduced expression of TGF-ß1 and its pathway genes (such as α-SMA and Snail). PPAR-γ regulation of Axl expression was through transcriptional activation of miR-92b. miR-92b expression downregulated Axl expression at both mRNA and protein levels, whereas GW9662 completely reversed the inhibitory effects of miR-92b mimics on Axl expression. Gene ontology analysis of miR-92b targeting genes showed that TGF-ß and Axl were both potential targets of miR-92b, as confirmed by luciferase assay. These findings demonstrated that PPAR-γ-induced miR-92b expression inhibited Axl expression and in turn reduced expression of TGF-ß1 and the downstream genes in KFs, suggesting that targeting of this novel gene pathway may be useful for therapeutic control of fibrosis or keloid.

Melatonin prevents acute kidney injury in severely burned rats via the activation of SIRT1.

Acute kidney injury (AKI) is a common complication after severe burns. Melatonin has been reported to protect against multiple organ injuries by increasing the expression of SIRT1, a silent information regulator that regulates stress responses, inflammation, cellular senescence and apoptosis. This study aimed to investigate the protective effects of melatonin on renal tissues of burned rats and the role of SIRT1 involving the effects. Rat severely burned model was established, with or without the administration of melatonin and SIRT1 inhibitor. The renal function and histological manifestations were determined to evaluate the severity of kidney injury. The levels of acetylated-p53 (Ac-p53), acetylated-p65 (Ac-p65), NF-κB, acetylated-forkhead box O1 (Ac-FoxO1), Bcl-2 and Bax were analyzed to study the underlying mechanisms. Our results suggested that severe burns could induce acute kidney injury, which could be partially reversed by melatonin. Melatonin attenuated oxidative stress, inflammation and apoptosis accompanied by the increased expression of SIRT1. The protective effects of melatonin were abrogated by the inhibition of SIRT1. In conclusion, we demonstrate that melatonin improves severe burn-induced AKI via the activation of SIRT1 signaling.

Peroxisome proliferator-activated receptor-γ agonist inhibits collagen synthesis in human keloid fibroblasts by suppression of early growth response-1 expression through upregulation of miR-543 expression.

A keloid is a benign skin tumor formed by an overgrowth of granulation tissue in affected patients. Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists were reported to be able to regulate extracellular matrix production in human dermal fibroblasts. This study explored the underlying molecular mechanism of PPAR-γ agonist troglitazone treatment for fibroblasts obtained from keloid patients. The data revealed that troglitazone treatment of keloid fibroblasts (KFs) downregulated the expression of early growth response-1 (Egr1) and collagen-1 (Col1). Level of Egr1 were closely associated with KF-induced fibrosis. The miRNA profiling data revealed that miR-543 was transcriptionally activated after troglitazone treatment. Bioinformatic analysis and experimental data showed that miR-543 was able to target Egr1. ELISA data confirmed that Col1 protein in the supernatant were modulated by the feedback regulatory axis of PPAR-γ agonist-induced miR-543 to inhibit Egr1 expression, whereas PPAR-γ antagonist treatment abolished such effect on Col1 suppression in KFs. This study demonstrated that the PPAR-γ agonist-mediated miR-543 and Egr1 signaling plays an important role in the suppression of collagen synthesis in KFs. Future in vivo studies are needed to confirm these in vitro data.