Predictive significance of Charcot-Leyden Crystal mRNA levels in nasal brushing for nasal polyp recurrence

BACKGROUND

Tissue eosinophils have been shown to be associated with polyp recurrence in chronic rhinosinusitis with nasal polyps (CRSwNP). We addressed whether the mRNA levels of Charcot-Leyden Crystal (CLC) in nasal brushing samples, a molecule mainly released from activated eosinophils, could serve as an effective non-invasive biomarker to predict polyp recurrence.

METHODS

A total of 51 patients with CRSwNP completing the postoperative follow-up over a period of 12-18 months were enrolled. Baseline CLC mRNA levels of the nasal brushings collected prior to endoscopic sinus surgery were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). Polyp specimens were collected during surgery and were evaluated for inflammatory cells by histopathologic staining. The patients' baseline characteristics were reviewed and analyzed for associations with recurrence. Logistic regression analysis was performed to determine the predictive factors for polyp recurrence, and receiver operating characteristic (ROC) curves were performed to determine their predictive values.

RESULTS

Overall, 25/51(49.02%) patients experienced polyp recurrence during the 12-18 months follow-up. The baseline relative CLC mRNA level in nasal brushing samples was significantly increased in patients with recurrence compared to those without recurrence (p.

GC-MS analysis of volatiles in cinnamon essential oil extracted by different methods

Cinnamon essential oil (CEO) was extracted by three different methods: steam distillation (SD), ultrasound-assisted steam distillation (UASD) and microwave-assisted steam distillation (MASD). The volatiles in CEO were separated and identified by gas chromatography–mass spectrometry (GC-MS), and the differences in volatiles among the three different methods were further analyzed through principal component analysis. The results showed that 36 individual volatile components were present in the CEO from the three different methods. In general, the numbers of aldehydes, esters, alcohols, terpenes, aromatics and ketones were 6, 3, 7, 17, 2, and 1, respectively. The most abundant volatile component was determined to be cinnamic aldehyde. The content of total cinnamic aldehydes, which determines the price of CEO, was the highest among the three methods in the UASD sample (85.633%). Moreover, the highest yield (8.33‰) of essential oil was extracted by the UASD method. Therefore, UASD was the best way for CEO extraction in this research and was recommended for future industrial applications.

In-vivo evaluation of a reinforced ovine biologic: a comparative study to available hernia mesh repair materials

Purpose

Two innovative reinforced biologic materials were studied in a non-human primate hernia repair model. The test articles, which combine layers of ovine decellularized extracellular matrix with minimal amounts of synthetic polymer, were evaluated for their biologic performance as measured by inflammatory response, healing kinetics, integration, and remodeling into functional host tissue. For comparison, seven clinically used biologic and synthetic meshes were also studied.

Methods

Animals were implanted with test articles in surgically created full-thickness midline abdominal wall defects, and evaluated macroscopically and histologically at 4, 12, and 24 weeks.

Results

Macroscopically, biologics resorbed and remodeled into naturally appearing tissue; the reinforced biologics appeared similar, but remodeled earlier and were less prone to stretch. Synthetics developed a layer of reactive tissue above and separate from the contracted mesh structure. At early time points, the collagen networks of biologics and reinforced biologics were infiltrated by host cells primarily as a peripheral layer on the biologics. As early as 12 weeks, the collagen networks associated with the reinforced biologics remodeled into organized host collagen. By 24 weeks, both reinforced biologics and biologics had low levels of inflammation. In contrast, a foreign body response persisted at 24 weeks with the synthetics, which had developed less organized collagen, separate in space from the actual mesh.

Conclusions

The current study shows a favorable response to reinforced biologics, which were associated with an initial inflammatory response, resolving by later time points, followed by active remodeling, and the formation of new morphologically functional collagen.

Electronic supplementary material

The online version of this article (10.1007/s10029-019-02119-z) contains supplementary material, which is available to authorized users.

A 9-year experience study of single-port micro-laparoscopic repair of pediatric inguinal hernia using a simple needle

Purpose

As laparoscopic techniques and equipments improve, laparoscopic inguinal hernia repair has been gaining popularity. The objective of the study was to summarize 9 years of experience using a single-port micro-laparoscopic approach to repair pediatric inguinal hernias with a simple hernia needle.

Methods

1880 children with inguinal hernias were enrolled using micro-laparoscopic surgery between June 2009 and 2018. All patients underwent high ligation surgery using a single-port micro-laparoscopic technique. The clinical data were retrospectively analyzed.

Results

All micro-laparoscopic surgeries were successfully performed in the 1880 patients, who ranged in age from 2 months to 14 years (3.66 ± 2.96 years) including 1622 males and 258 females. Among them, 1299 cases were unilateral hernias and 581 cases were bilateral hernias. The average operating time was 12.5 ± 3.5 min for a unilateral hernia and 20.5 ± 4.5 min for bilateral hernias. All patients were discharged 1–2 days after surgery, and the average length of their hospital stay was 2–4 days. Complications of knot reaction and pneumoscrotum occurred in 5 cases (0.27%) and 54 cases (2.87%), respectively, but these cases were properly managed, with no major impact on the operational outcomes. All patients were followed up for 3–65 months; there were 13 recurrent cases (0.69%).

Conclusions

Single-port micro-laparoscopic herniorrhaphy in children using a simple hernia needle is a reliable and minimally invasive procedure.

Selective debridement of burn wounds using hydrosurgery system

In recent years, hydrosurgery is a technology that has been applied more and more in debridement procedures. However, the selectivity of hydrosurgery to cutaneous necrotic tissues has not been proved. This study was designed to investigate the possible tissue selectivity of hydrosurgery in the debridement in burn wounds. Deep partial-thickness burns were produced on the back of porcine, and 48 hours later, both burn wounds and normal skin were debrided using the hydrosurgery system. Then tissue samples were taken, and histological staining was performed and observed under microscope. Burn wound resection rates and the normal skin damaged rates were measured. Our result indicated that the burn wounds were significantly more sensitive than the normal skin when the water pressure produced by the hydrosurgery system was set between 3000 and 5000 psi (pounds per square inch), that is, the necrotic tissue portions were debrided more easily than the normal skin tissue. Based on these data, we suggest that 3000 to 5000 psi of water pressure in the hydrosurgery system has a skin tissue selectivity in burn wounds.

A Systematic Review and Meta-Analysis of Clinical Effectiveness and Safety of Hydrogel Dressings in the Management of Skin Wounds

The purpose of this systematic review and meta-analysis is to assess the clinical effectiveness and safety of the medical hydrogel dressings used in skin wounds and therefore to weight the evidence for their clinical application. PubMed/Medline (1980–2019), Cochrane Library (1980–2019), ClinicalTrials.gov, Cochrane CENTRAL, Chinese Journal Full-text Database (CNKI, 1994–2019), and China Biomedy Medicine disc (CBM, 1978–2019), Chinese Scientific Journal Database (VIP, 1989–2019), and Wanfang Database (WFDATA, 1980–2019) were searched to identify relevant clinical trials and studies. Forty-three studies that assessed hydrogel vs. non-hydrogel dressings were identified. Compared to the latter, hydrogel dressings associated with a significantly shortened healing time of degree II burn (superficial and deep) wounds, diabetic foot ulcers, traumatic skin injuries, radioactive skin injuries, dog bites, and body surface ulcers. In addition, hydrogel dressing obviously increased the cure rate of diabetic foot ulcers, surgical wounds, dog bites, and body surface ulcers. Moreover, hydrogel dressing significantly relieved pain in degree II burn (superficial and deep) wounds, traumatic skin injuries, and laser treatment-induced wounds. However, no significant differences obtained between hydrogel and non-hydrogel dressings in the healing time of surgical wounds, the cure rate of inpatients' pressure ulcers, and phlebitis ulcers. This comprehensive systematic review and meta-analysis of the available evidence reveals that the application of hydrogel dressings advances the healing of various wound types and effectively alleviates the pain with no severe adverse reactions. These results strongly indicate that hydrogel products are effective and safe in wound management.

Prevascularized mesenchymal stem cell-sheets increase survival of random skin flaps in a nude mouse model

A random skin flap is commonly applied in plastic and reconstructive surgery. The distal part of the random skin flap often risks necrosis because the blood flow may be compromised. Prevascularization is a widely used technology to intensify the vascularization function of biomaterials. In fact, human mesenchymal stem cell (hMSC) sheets promote neoangiogenesis. We speculated that prevascularized hMSC cell sheets (PHCS) would further improve neovascularization by producing more angiogenic growth factors in a random skin flap animal model. In this study, PHCS were set up by co-culturing human umbilical vein endothelial cells (HUVECs) with hMSC cell sheets (HCS). In vitro, we observed microvessel formation and significantly increased production of angiogenesis-related factors. Thus, we analyzed the microvessel networks, vascular maturation, and angiogenic growth factors of the cell sheet. In vivo, PHCS and HCS were implanted in a murine ischemic random skin flap model. Implanted PHCS significantly increased blood perfusion and improved skin flap survival when compared to untreated control skin flaps. The survival rate of the prevascularized and control skin flaps was assessed after 3, 5, and 7 days via analysis of macroscopic images and Laser Doppler Perfusion Imaging (LDPI). Additionally, the numbers of skin appendages, collagen fibers deposition, and epidermal thickness were evaluated. Moreover, the PHCS group also induced the most intense neovascularization, the upshot of which was a robust blood microcirculation supporting skin flap survival. Therefore, PHCS implantation can effectively enhance local neoangiogenesis and hence increase the survival of otherwise ischemic skin flaps. Hence, local administration of PHCS may serve as an alternative approach in improving random skin flap survival.

Role of caveolin-1 in epidermal stem cells during burn wound healing in rats

Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing.

Curcumin promotes burn wound healing in mice by upregulating caveolin-1 in epidermal stem cells

We aimed to explore the effect of curcumin on epidermal stem cells (ESCs) in regulating wound healing and the underlying molecular mechanism. We treated mouse ESCs isolated from skin tissues with curcumin, and then assessed the proliferation ability of cells induced by epidermal growth factor using cell counting kit-8 assay. The pluripotency of ESCs was evaluated as well through examination of Nanog expression in ESCs. Further, mice with skin burns were treated with ESCs with or without curcumin pretreatments. Histological evaluations were then preformed to determine wound scores, cell proliferation, reepithelialization, and capillary density in wounds. Curcumin treatment promoted the proliferative ability of ESCs and conditioned medium from curcumin-treated ESCs enhanced human umbilical vein endothelial cell (HUVEC) tube formation. We also found curcumin treatment elevated caveolin-1 expression in ESCs, which was required for the beneficial effect of curcumin on ESC proliferation and HUVEC tube formation. Next, using a mouse model of burn wound healing, curcumin-treated ESCs exhibited enhanced wound closure, which also required caveolin-1 expression. Our current study demonstrates the beneficial effect of curcumin on burn wound healing in mice, which is mediated by upregulating caveolin-1 in ESCs, and supports the potential therapeutic role of curcumin in ESC-based treatment against skin wound healing.

microRNA-203 Modulates Wound Healing and Scar Formation via Suppressing Hes1 Expression in Epidermal Stem Cells

BACKGROUND/AIMS

Little is known how miR-203 is involved in epidermal stem cells (ESCs) differentiation and scar formation.

METHODS

We first used luciferase assay to determine the interaction of miR-203 with the 3'-UTR in regulation of Hes1 expression. We then used flow cytometry to analyze the effects of miR-203 expression on the differentiation of ESCs to MFB by determination of CK15 ratio and α-SMA. To confirm the results of flow cytometry analysis, we used Western blot to examine the expression of α-SMA, Collagen I (Col I), and Collagen III (Col III), as well as the expression of Notch1, Jagged1, and Hes1 in ESCs after the treatment of pre-miR-203 or anti-miR-203. Finally, we examined the effects local anti-miR-203 treatment on would closure and scar formation using a mouse skin wound model.

RESULTS

Pre-miR-203 treatment increased ESCs differentiation to MFB cells, as indicated by decreased CK15 ratio and increased MFB biomarkers. This phenomenon was reversed by overexpression of Hes1 in ESCs. In addition, skin incision increased expression of miR-203 in wound tissue. Local treatment of anti-miR-203 could accelerate wound closure and reduce scar formation in vivo, which was associated with increased re-epithelialization, skin attachment regeneration, and collagen reassignment. Finally, we confirmed that anti-miR-203 treatment could inhibit ESCs differentiation in vivo via increasing Hesl expression.

CONCLUSION

Taken together, our results suggested that overexpression of miR-203 in ESCs after skin wound may be a critical mechanism underlying the scar formation.

An immune-competent rat split thickness skin graft model: useful tools to develop new therapies to improve skin graft survival

Skin grafting is the routine standard of care to manage third degree burns and problematic skin defects. Several commercially available dermal substitutes and biologic skin equivalents are placed in the wound bed to facilitate the healing process of the skin grafts, as well as to provide mechanical support for the cells to grow and to delay the contracture. To study pathology and develop new therapies, an immune-competent rat model is required. We have created two different skin graft animal models to mimic the clinical skin grafting operation, the dorsum skin grafting (DG) and inguinal skin grafting (IG). To create a recipient site, a full-thickness, round excision wound was created on the dorsum between rats' scapular angles, covered with DG or IG. Graft contraction was quantified and tissue was harvested on predetermined time points for analysis. Histologic staining was performed to differentiate between DG and IG. Collagen deposition was assessed with Masson's trichrome staining. Mast cells were detected with Toluidine blue. Macrophages were stained with CD68 immune. Vascularity was assessed with functional vessels numbers. Cell proliferation was assessed with Ki67 immune. This model has all the advantages of murine models, such as an abundance of genetic variants and applicable tools, low cost, and practical housing techniques, all of which will promote the development of new therapies and testing new biologic skin equivalents and dermal substitutes.

Early-stage mantle cell lymphoma: a retrospective analysis from the International Lymphoma Radiation Oncology Group (ILROG)

Background

Mantle cell lymphoma (MCL) rarely presents as early-stage disease, but clinical observations suggest that patients who present with early-stage disease may have better outcomes than those with advanced-stage disease.

Patients and methods

In this 13-institution study, we examined outcomes among 179 patients with early-stage (stage I or II) MCL in an attempt to identify prognostic factors that influence treatment selection and outcome. Variables examined included clinical characteristics, treatment modality, response to therapy, sites of failure, and survival.

Results

Patients were predominantly male (78%) with head and neck being the most common presenting sites (75%). Most failures occurred outside the original disease site (79%). Although the administration of radiation therapy, either alone or with chemotherapy, reduced the risk of local failure, it did not translate into an improved freedom from progression or overall survival (OS). The treatment outcomes were independent of treatment modality. The 10-year OS for patients treated with chemotherapy alone, chemo-radiation therapy and radiation therapy alone were 69%, 62%, and 74% (P = 0.79), and the 10-year freedom from progression were 46%, 43%, and 31% (P = 0.64), respectively.

Conclusion

Given the excellent OS rates regardless of initial therapy in patients with early-stage MCL, de-intensified therapy to limit treatment-related toxicity is a reasonable approach.

Epidermal HMGB1 Activates Dermal Fibroblasts and Causes Hypertrophic Scar Formation in Reduced Hydration

HMGB1 protein is a multifunctional cytokine involved in inflammatory reactions and is known to play a key role in tissue repair and fibrosis. However, the function of HMGB1 in fibrotic skin diseases, such as hypertrophic scar formation, remains unclear. In this study, HMGB1 was detected in the nuclei of epidermal cells in normal skin and had accumulated in the cytoplasm in hypertrophic scars. By establishing a keratinocyte-fibroblast co-culture and conditional medium treatment models, we found that a reduced hydration condition increased the expression and secretion of HMGB1 in keratinocytes, subsequently activating dermal fibroblasts. HMGB1 secreted from keratinocytes activated fibroblasts by promoting the nuclear import of MRTF-A, increased the nuclear accumulation of MRTF-A/SRF complexes and consequently enhanced α-smooth muscle actin promoter activation. Moreover, blockade of advanced glycation end products or Toll-like receptor 2/4 inhibited the fibroblast activation induced by HMGB1. Finally, local delivery of HMGB1 resulted in marked hypertrophic scar formation in rabbit hypertrophic scar models, while HMGB1 blockade exerted a clear anti-scarring effect. Our results indicate that high HMGB1 levels induced by a reduced hydration status play an important role in hypertrophic scar formation, strongly suggesting that HMGB1 is a novel target for preventing scarring.

Clinical application of protein biomarkers in lupus erythematosus and lupus nephritis

Systemic lupus erythematosus (SLE) is a type of autoimmune disease that damages multiple organs, including the heart, joints, liver and kidneys. The main characteristics of SLE are the deposition of circulating autoantibodies; autoantigen complexes in the renal system; and abnormal expression of complements, cytokines and chemokines. Lupus nephritis (LN) is the most serious manifestation of SLE and is characterized by inflammation of the kidney. This review summarizes recent clinical applications of protein biomarkers including autoantibodies, complements, cytokines and chemokines and some new protein biomarkers in SLE and LN. The clinical differential diagnosis of protein biomarkers related to prognosis and diagnosis is discussed and highlighted. Protein biomarkers play crucial roles in the study of SLE and LN. Useful biomarkers will provide insights into effective treatments for these diseases.

Long-term outcome of 487 patients with early-stage extra-nodal marginal zone lymphoma

Background

Localized early-stage extra-nodal marginal zone lymphoma (MZL) presents with heterogeneous organ involvement and is treated with various modalities, including resection, radiotherapy, and systemic therapy. We report the long-term outcome of a large cohort of extra-nodal MZL and assess the impact of patient and disease characteristics, organ site, and treatment strategy on disease control and survival.

Patients and methods

We identified 487 consecutive patients with stage IE or IIE MZL referred between 1992 and 2012 to Memorial Sloan Kettering Cancer Center. Pathology was reviewed by hematopathologists at our institution. Patient and disease factors as well as treatment types were analyzed for association with relapse-free survival, overall survival, and cumulative incidence of relapse.

Results

Median follow-up after treatment was 4.7 years. Five-year relapse-free survival and overall survival were 60% and 89%, respectively. Cumulative incidence of disease-specific death at 5 years was 1.3%. Radiotherapy alone was the initial treatment in 50% of patients, followed by surgical resection (30%), observation (8%), immunotherapy (4%), and chemotherapy (2%). Initial treatment type, primary disease site, and number of involved sites were significant factors in multivariable analysis of relapse (all P < 0.05). When compared with stomach, MZL originating in other disease sites (HR > 2.0, P ≤ 0.001), except for thyroid, had higher risk of relapse. Strategies such as antibiotics or topical therapies were associated with higher risk of relapse when compared with radiation therapy (P < 0.001). Crude rate of transformation to pathologically confirmed large-cell lymphoma was 2% (11 patients).

Conclusion

Overall and cause-specific survival are high in early-stage extra-nodal MZL. Curative-intent treatment led to fewer relapses and reduced the need for salvage. Stomach cases had lower risk of relapse than other anatomic primary sites. This study supports the use of local therapies to treat stage IE and IIE MZL.

Prevascularization of natural nanofibrous extracellular matrix for engineering completely biological three-dimensional prevascularized tissues for diverse applications

Self-sustainability after implantation is one of the critical obstacles facing large engineered tissues. A preformed functional vascular network provides an effective solution for solving the mass transportation problem. With the support of mural cells, endothelial cells (ECs) can form microvessels within engineered tissues. As an important mural cell, human mesenchymal stem cells (hMSCs) not only stabilize the engineered microvessel network, but also preserve their multi-potency when grown under optimal culture conditions. A prevascularized hMSC/extracellular matrix (ECM) sheet fabricated by the combination of hMSCs, ECs and a naturally derived nanofibrous ECM scaffold offers great opportunity for engineering mechanically strong and completely biological three-dimensional prevascularized tissues. The objective of this study was to create a prevascularized hMSC/ECM sheet by co-culturing ECs and hMSCs on a nanofibrous ECM scaffold. Physiologically low oxygen (2% O2 ) was introduced during the 7 day hMSC culture to preserve the stemness of hMSCs and thereby their capability to secrete angiogenic factors. The ECs were then included to form microvessels under normal oxygen (20% O2 ) for up to 7 days. The results showed that a branched and mature vascular network was formed in the co-culture condition. Angiogenic factors vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and angiopoietin-1 (Ang-1) were significantly increased by low-oxygen culture of hMSCs, which further stabilized and supported the maturation of microvessels. A differentiation assay of the prevascularized ECM scaffold demonstrated a retained hMSC multi-potency in the hypoxia cultured samples. The prevascularized hMSC/ECM sheet holds great promise for engineering three-dimensional prevascularized tissues for diverse applications.

Negatively-charged aerosol improves burn wound healing by promoting eNOS-dependent angiogenesis

Aerosols exist in the form of liquid or solid particles that stably suspending in air. Our previous studies have found that aerosol can accelerate chronic wound healing. However, the biological effects of aerosol in burn wound healing and the underlying molecular mechanism remain unclear. This study aimed to investigate the effects of aerosol on the healing of deep partial-thickness burn wounds and its regulatory mechanisms. By employing a self-controlled model of rats, we demonstrated that aerosol treatment not only increased the healing rate, but also improved the healing quality of deep partial-thickness burn wounds. Besides, the excessive inflammatory responses in the burn wounds were inhibited, and the angiogenesis was increased after aerosol treatment. It did so by upregulating the expression of eNOS/NO, as well as the VGEF expression during the wound healing process. Our results demonstrate that the function of aerosol in promoting burn wound healing is achieved by activating eNOS/NO pathway.

Brassica napusGLABRA3-1 promotes anthocyanin biosynthesis and trichome formation in true leaves when expressed in Arabidopsis thaliana

Previous studies have shown that GLABRA3 (AtGL3), a bHLH transcription factor, plays essential roles in anthocyanin biosynthesis and trichome formation in Arabidopsis thaliana. However, there have been no such studies of a homologue, BnGL3, from the closely related crop, Brassica napus. Here, we analysed the BnGL3-1 coding domain sequence from the B. napus cultivar QINYOU Seven, identified conserved protein domains and performed a phylogenetic analysis to elucidate its relationship with homologues form a range of plant species. When expressed in tobacco leaves as a fusion protein with green fluorescent protein, BnGL3-1 accumulated in the nucleus, consistent with its predicted function as a transcription factor. Ectopic expression of the BnGL3-1 gene in the A. thaliana gl3-3 mutant resulted in levels of anthocyanins and numbers of trichomes in true leaves that were higher than in wild-type plants. Moreover, overexpression of BnGL3-1 in gl3-3 compensated for the promotion and repression of genes involved in anthocyanin biosynthesis and trichome formation, respectively, that has been reported in gl3-3 young shoots and expanding true leaves. This study provides new insights into GL3 function in anthocyanin biosynthesis and trichome formation in crucifers, and represents a promising target for genetic manipulation of B. napus.

Scarless Wound Closure by a Mussel-Inspired Poly(amidoamine) Tissue Adhesive with Tunable Degradability

Burn, trauma, and various medical conditions including bacterial infection, diabetes complication, and surgery could lead to an acute cutaneous wound and scar formation. Application of tissue glues instead of sutures could minimize the additional trauma and scar formation. Despite the countless efforts devoted to the development of high-strength tissue glues, little attention has been paid to their influence on the scar formation. Here, we report the development of a new tissue glue with excellent biocompatibility and tunable degradability for scarless wound closure. A series of catechol-containing poly(amidoamine) (CPAA) polymers were synthesized via the one-step Michael addition of dopamine and bisacrylamide. The tertiary amino group in the polymer backbone was used to introduce a zwitterionic sulfobetaine group by one-step ring-opening polymerization. The introduction of the zwitterionic sulfobetaine group could easily tune the hydrophilicity and the degradability of CPAA without influencing the density of the catechol group in the polymer. Lap-shear tests on the porcine skin demonstrated a high adhesion strength of 7 kPa at 1 h, rising to 24 kPa by 12 h. Addition of silica nanoparticles could further enhance the adhesion strength by 50%. In vivo studies further confirmed that the CPAA tissue glue could effectively accelerate the healing process of incisional wounds on the back of Sprague Dawley rats compared with suture and reduce the scar formation.

Basic fibroblast growth factor reduces scar by inhibiting the differentiation of epidermal stem cells to myofibroblasts via the Notch1/Jagged1 pathway

Background

Basic fibroblast growth factor (bFGF) plays an important role in promoting wound healing and reducing scar, but the possible molecular mechanisms are still unclear. Our previous studies have found that activating the Notch1/Jagged1 pathway can inhibit the differentiation of epidermal stem cells (ESCs) to myofibroblasts (MFB). Herein, we document that bFGF reduces scar by inhibiting the differentiation of ESCs to MFB via activating the Notch1/Jagged1 pathway.

Methods

In in-vitro study, ESCs were isolated from 10 neonatal SD rats (1–3 days old), cultured in keratinocyte serum-free medium, and divided into six groups: bFGF group, bFGF + SU5402 group, bFGF + DAPT group, siJagged1 group, bFGF + siJagged1 group, and control group. Jagged1 of the ESCs in the siJagged1 group and bFGF + siJagged1 group was knocked down by small-interfering RNA transfection. Expression of ESC markers (CK15/CK10), MFB markers (α-SMA, Collagen I, Collagen III), and Notch1/Jagged1 components (Jagged1, Notch1, Hes1) was detected by FCM, qRT-PCR, and western blot analysis to study the relationships of bFGF, ESCs, and Notch1/Jagged1 pathway. In in-vivo study, the wound healing time and scar hyperplasia were observed on rabbit ear scar models. The quality of wound healing was estimated by hematoxylin and eosin staining and Masson staining. Expression of ESC markers, MFB markers and Notch1/Jagged1 components was elucidated by immunohistochemistry, immunofluorescence, and western blot analysis.

Results

The in-vitro study showed that bFGF could significantly upregulate the expression of ESC markers and Notch1/Jagged1 components, while downregulating the expression of MFB markers at the same time. However, these effects could be obviously decreased when we knocked down Jagged1 or added DAPT. Similarly, in in-vivo study, bFGF also exhibited its functions in inhibiting the differentiation of rabbit ESCs to MFB by activating the Notch1/Jagged1 pathway, which improved the wound healing quality and alleviated scar significantly.

Conclusion

These results provide evidence that bFGF can reduce scar by inhibiting the differentiation of ESCs to MFB via the Notch1/Jagged1 pathway, and present a new promising potential direction for the treatment of scar.