Growth Factor bFGF Research Articles

Understanding Platelet-Rich Plasma as Potential Therapy To Improve Cardiac Function After Myocardial Infarction: Based On Evidence

Myocardial infarction is the leading cause of death in the world’s population. The sudden and progressive loss of cardiomyocyte contractile cells due to infarction is disproportionate to the number of new cells formation. This pathological condition will ultimately reduce the function of the heart muscles. Platelet-rich plasma (PRP) in the last decade has been attracting attention regarding its role in cell regeneration. The content of cytokines and growth factors contained in PRP such as Platelet-Derived Growth Factor (PDGF), Transforming Growth Factor Beta 1 (TGF-Β1), Epidermal Growth Factor (EGF), Vascular Endothelial Growth Factor (VEGF), Basic Fibroblast Growth Factor (bFGF) and others are known to be involved in the migration, proliferation, and differentiation of various cell types and to induce post-ischemic angiogenesis. This review aims to analyze and investigate the benefits of PRP therapy in myocardial infarction. Recent literatures regarding the use of PRP in myocardial infarction was collected by searching PubMed and Google Scholar databases with the keywords of “Platelet-rich plasma”, “Myocardial Infarction”, “Reperfusion”, and “Angiogenesis”. The researches used was published between January 2011 and December 2022. Based on the results, Platelet-rich Plasma (PRP) is considered capable of accelerating angiogenesis, mitogenesis, protect cells from free radicals, reduce infarct area and scar tissue in myocardial infarction. PRP can also improve cardiac function in post myocardial infarction by increasing ejection fraction. In addition, PRP can also reduce treatment costs due to the risk of myocardial infarction complications such as bleeding and infection.

The Effect of Growth Factors on Vaginal Wound Healing: A Systematic Review and Meta-analysis.

Surgical outcomes of pelvic organ prolapse (POP) surgery are poor, resulting in a 20% recurrence risk. Following the hypothesis that impaired wound healing is the main determinant of recurrent POP, growth factors have the potential to promote wound healing and may improve surgical outcomes. In this study, we systematically reviewed the effect of growth factors on vaginal wound healing in both in vitro and animal studies. For each independent comparison, the standardized mean difference and 95% CI were calculated using the Hedges' g correction. Of the 3858 retrieved studies, seven studies were included, of which six were included in meta-analysis (three in vitro studies and four in vivo studies). In vitro, basic fibroblast growth factor (bFGF) promotes proliferation, differentiation, and collagen types I and III production. Epidermal growth factor stimulates proliferation and connective tissue growth factor promotes Tenascin-C expression. These effects, however, are less pronounced in vivo; only bFGF slightly promotes collagen production. The review shows that growth factors, particularly bFGF, are able to promote vaginal wound healing in vitro. The uncertain in vivo findings suggest that preclinical models should be improved. The ultimate goal is to develop effective growth factor-supplemented therapies that improve surgical outcomes for POP.

Biomaterial-Based bFGF Delivery for Nerve Repair.

Diseases in the nervous system are common in the human body. People have to suffer a great burden due to huge economic costs and poor prognosis of the diseases. Many treatment modalities are now available that can make recovery better. Managing nutritional factors is also helpful for such diseases. The basic fibroblast growth factor (bFGF) is one of the major nutritional factors, which plays a crucial role in organogenesis and tissue homeostasis. It plays a role in cell proliferation, migration, and differentiation, thereby regulating angiogenesis and wound healing and repair of the muscle, bone, and nerve. The study on how to improve the stability of bFGF to increase the treatment effect for different diseases has garnered tremendous attention. Biomaterials are the popular methods to improve the stability of bFGF because they are safe for the living body as they are biocompatible. Biomaterials can be loaded with bFGF and delivered locally to achieve the goal of sustained bFGF release. In the present review, we report different types of biomaterials that are used for bFGF delivery for nerve repair and briefly report how the introduced bFGF can function in the nervous system. We aim to provide summative guidance for future studies about nerve injury using bFGF.

Inhibition of FGFR2 Signaling by Cynaroside Attenuates Liver Fibrosis.

Liver fibrosis represents a significant health hazard with a high morbidity rate and an increased risk of liver cancer. Targeting overactivated Fibroblast growth factor receptor 2 (FGFR2) is a promising strategy to counteract collagen accumulation during liver fibrosis. However, there is a shortage of drugs to specifically block the activation of FGFR2 in liver fibrosis patients. Data mining, cell validation, and animal studies showed a positive correlation between FGFR2 overexpression and liver fibrosis development. Novel FGFR2 inhibitors were screened using a microarray-based high-throughput binding analysis. The effectiveness of each candidate was validated through simulated docking, binding affinity verification, single-point mutation validation, and in vitro kinase inhibition measurements to demonstrate the ability of each inhibitor to block the catalytic pocket and reverse FGFR2 overactivation. A specific FGFR2 inhibitor, cynaroside (CYN, also known as luteoloside), was screened based on the finding that FGFR2 promotes hepatic stellate cell (HSC) activation and collagen secretion in hepatocytes. The results from cellular assays showed that CYN can inhibit FGFR2 hyperactivation resulting from its overexpression and excessive basic fibroblast growth factor (bFGF), reducing HSC activation and collagen secretion in hepatocytes. Animal experiments on a carbon tetrachloride (CCl4) mouse model and a nonalcoholic steatohepatitis mouse model indicate that CYN treatment reduces liver fibrosis during fibrosis formation. These findings suggest that CYN prevents liver fibrosis formation at the cell level and in mouse models.

Biomimetic Janus Collagen Patch with Antideformation, Antiadhesion, and Prohealing Properties for Rehabilitation of Full‐Layer Uterine Injuries, Toward Efficient Live Births

AbstractUterine abnormalities infertility can be treated with implantable patches for tension‐free healing. However, the existing clinical patches are still limited in effective uterus recovery, resulting in low pregnancy and live birth rates. Herein, a novel engineered, and biocompatible Janus collagen patch (JCOP) is developed to achieve excellent uterine defect recovery and increase effective live births. The JCOP can highly match the structure, micromorphology, and mechanical properties of a natural uterus due to homologous‐like tissue homogeneity. JCOP's rough surface and loose‐extracellular‐matrix‐like porosity promote fibroblast adhesion and tissue regeneration, whereas its smooth surface reduces fibroblast adhesion and prevents visceral adhesions. Additionally, it exhibits exceptional resistance to swelling and deformation along with stable mechanical strength for long‐term preservation in the body and can withstand the highest uterine pressure in a humid interior environment attributed to its superior structural layout. Moreover, JCOP@bF, a functional JCOP linked to basic fibroblast growth factor (bFGF) via a specific collagen‐binding domain, significantly promotes repair of the injured uterus, restores the ability of the endometrium to accept embryos, and supports their development to a viable stage in a rat model of uterine damage. This study shows great promise for treating infertility caused by uterine damage.

Photobiomodulation at 660 nm Stimulates In Vitro Diabetic Wound Healing via the Ras/MAPK Pathway

Diabetic foot ulcers (DFUs) are open chronic wounds that affect diabetic patients due to hyperglycaemia. DFUs are known for their poor response to treatment and frequently require amputation, which may result in premature death. The present study evaluated the effect of photobiomodulation (PBM) at 660 nm on wound healing via activation of Ras/MAPK signalling in diabetic wounded cells in vitro. This study used four human skin fibroblast cell (WS1) models, namely normal (N), wounded (W), diabetic (D), and diabetic wounded (DW). Cells were irradiated at 660 nm with 5 J/cm2. Non-irradiated cells (0 J/cm2) served as controls. Cells were incubated for 24 and 48 h post-irradiation, and the effect of PBM on cellular morphology and migration rate, viability, and proliferation was assessed. Basic fibroblast growth factor (bFGF), its phosphorylated (activated) receptor FGFR, and phosphorylated target proteins (Ras, MEK1/2 and MAPK) were determined by enzyme-linked immunosorbent assay (ELISA) and Western blotting; nuclear translocation of p-MAPK was determined by immunofluorescence. PBM resulted in an increase in bFGF and a subsequent increase in FGFR activation. There was also an increase in downstream proteins, p-Ras, p-MEK1/2 and p-MAPK. PBM at 660 nm led to increased viability, proliferation, and migration as a result of increased bFGF and subsequent activation of the Ras/MAPK signalling pathway. Therefore, this study can conclude that PBM at 660 nm stimulates in vitro diabetic wound healing via the bFGF-activated Ras/MAPK pathway.

Effect of naringenin on the anti-inflammatory, vascularization, and osteogenesis differentiation of human periodontal ligament stem cells via the stromal cell-derived factor 1/C-X-C motif chemokine receptor 4 signaling axis stimulated by lipopolysaccharide.

This study aimed to investigate how naringenin (Nar) affected the anti-inflammatory, vascula-rization, and osteogenesis differentiation of human periodontal ligament stem cells (hPDLSCs) stimulated by lipopolysaccharide (LPS) and to preliminarily explore the underlying mechanism. Cell-counting kit-8 (CCK8), cell scratch test, and Transwell assay were used to investigate the proliferation and migratory capabilities of hPDLSCs. Alkaline phosphatase (ALP) staining, alizarin red staining, lumen-formation assay, enzyme-linked immunosorbent assay, quantitative timed polymerase chain reaction, and Western blot were used to measure the expression of osteopontin (OPN), Runt-related transcription factor 2 (RUNX2), vascular endothlial growth factor (VEGF), basic fibroblast growth factor (bFGF), von Willebrand factor (vWF), tumor necrosis factor-α (TNF-α), and interleukin (IL)-6. We observed that 10 μmol/L Nar could attenuate the inflammatory response of hPDLSCs stimulated by 10 μg/mL LPS and promoted their proliferation, migration, and vascularization differentiation. Furthermore, 0.1 μmol/L Nar could effectively restore the osteogenic differentiation of inflammatory hPDLSCs. The effects of Nar's anti-inflammatory and promotion of osteogenic differentiation significantly decreased and inflammatory vascularization differentiation increased after adding AMD3100 (a specific CXCR4 inhibitor). Nar demonstrated the ability to promote the anti-inflammatory, vascularization, and osteogenic effects of hPDLSCs stimulated by LPS, and the ability was associated with the stromal cell-derived factor/C-X-C motif chemokine receptor 4 signaling axis.

Basic fibroblast growth factor-loaded methacrylate gelatin hydrogel microspheres for spinal nerve regeneration.

Spinal cord injury is a severe central nervous system injury, and developing appropriate drug delivery platforms for spinal nerve regeneration is highly anticipated. Here, we propose a basic fibroblast growth factor (bFGF)-loaded methacrylate gelatin (GelMA) hydrogel microsphere with ideal performances for spinal cord injury repair. Benefitting from the precise droplet manipulation capability of the microfluidic technology, the GelMA microspheres possess uniform and satisfactory size and good stability. More importantly, by taking advantage of the porous structures and facile chemical modification of the GelMA microspheres, bFGF could be easily loaded and gradually released. By co-culturing with neural stem cells, it is validated that the bFGF-loaded GelMA microspheres could effectively promote the proliferation and differentiation of neural stem cells. We also confirm the effective role of the bFGF-loaded GelMA microspheres in nerve repair of spinal cord injury in rats. Our results demonstrate the potential value of the microspheres for applications in repairing central nervous system injuries.

Fibrin clot and Leukocyte-rich platelet-rich fibrin show similar release kinetics and amount of growth factors: a pilot study

BackgroundIn knee arthroscopic surgery, fibrin clot (FC) and leukocyte-rich platelet-rich fibrin (L-PRF) may be used in augmentation for meniscal repair. Studies have investigated growth factors released from FC and L-PRF; however, it is difficult to compare FC and L-PRF between different studies. Direct comparison of growth factors that may support meniscal healing released from FC and L-PRF may be beneficial in deciding whether to use FC or L-PRF. If no significant difference is seen, the surgeon may decide to use FC which is easier to prepare compared to L-PRF. The purpose of this pilot study is to investigate the release amount and pattern of basic fibroblast growth factor (bFGF), platelet-derived growth factor AB (PDGF-AB), transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF), and stromal cell-derived factor 1 (SDF-1) from FC and L-PRF.MethodTwenty milliliters (ml) of whole blood was collected from each of the four volunteers. Ten milliliters of whole blood was allocated for preparation of FC and 10 ml for L-PRF. FC and L-PRF were separately placed in 5 ml of culture media. Five milliliters of the culture media was sampled and refilled at 15 min, 1 day, 3 days, 1 week and 2 weeks. The collected culture was used to quantify bFGF, PDGF-AB, TGF-β1, VEGF, and SDF-1 release by Enzyme-linked immune-sorbent assay (ELISA). Mann–Whitney U test was performed to assess significance of differences in amount of each growth factor released between FC and L-PRF. Significance was accepted at P value less than 0.05.ResultsAt two weeks, the cumulative release of TGF-β1 was the highest among all the growth factors in both FC and L-PRF (FC:19,738.21 pg/ml, L-PRF: 16,229.79 pg/ml). PDGF-AB (FC: 2328 pg/ml, L-PRF 1513.57 pg/ml) had the second largest amount, followed by VEGF (FC: 702.06 pg/ml, L-PRF 595.99 pg/ml) and bFGF (FC: 23.48 pg/ml, L-PRF 18.2 pg/ml), which order was also common in both FC and L-PRF. No significant difference in final release amount and pattern was seen between FC and L-PRF.ConclusionThe current pilot study showed that cumulative release amount and release pattern of PDGF-AB, VEGF, TGF-β1, and bFGF did not significantly differ between FC and L-PRF during the two weeks of observation.

Basic Fibroblast Growth Factor Promotes Mesenchymal Stem Cell Migration by Regulating Glycolysis-Dependent β-Catenin Signaling.

Migration of mesenchymal stem cells (MSCs) to the site of injury is crucial in transplantation therapy. Studies have shown that cell migration is regulated by the cellular microenvironment and accompanied by changes in cellular metabolism. However, limited information is available about the relationship between MSC migration and cellular metabolism. Here, we show that basic fibroblast growth factor (bFGF) promotes the migration of MSCs with high levels of glycolysis and high expression of hexokinase 2 (HK2), a rate-limiting enzyme in glycolysis. The enhancement of glycolysis via the activation of HK2 expression promoted the migration of MSCs, whereas the inhibition of glycolysis, but not of oxidative phosphorylation, inhibited the bFGF-induced migration of these cells. Furthermore, bFGF enhanced glycolysis by increasing HK2 expression, which consequently promoted β-catenin accumulation, and the inhibition of glycolysis inhibited the bFGF-induced accumulation of β-catenin. When the accumulation of glycolytic intermediates was altered, phosphoenolpyruvate was found to be directly involved in the regulation of β-catenin expression and activation, suggesting that bFGF regulates β-catenin signaling through glycolytic intermediates. Moreover, transplantation with HK2-overexpressing MSCs significantly improved the effect of cell therapy on skull injury in rats. In conclusion, we propose a novel glycolysis-dependent β-catenin signaling regulatory mechanism and provide an experimental and theoretical basis for the clinical application of MSCs.

Neuronal differentiation and functional maturation of neurons from neural stem cells induced by bFGF-chitosan controlled release system.

Available methods for differentiating stem cells into neurons require a large number of cytokines and neurotrophic factors, with complex steps and slow processes, and are inefficient to produce functional neurons and form synaptic contacts, which is expensive and impractical in clinical application. Here, we demonstrated a bioactive material, basic fibroblast growth factor (bFGF)-chitosan controlled release system, for facilitating neuronal differentiation from NSCs and the functional maturation of the induced neurons with high efficiency. We illustrated by immunostaining that the neurons derived from NSCs expressed mature immunomarkers of interneurons and excitatory neurons. And we found by patch-clamp that the induced neurons exhibited diverse electrophysiological properties as well as formed functional synapses. In vivo, we implanted bFGF-chitosan into lesion area in traumatic brain injury (TBI) mice and similarly observed abundance of neuroblasts in SVZ and the presence of newborn functional neurons in injury area, which integrated into synaptic networks. Taken together, our efficient and rapid tissue engineering approach may be a potential method for the generation of functional neuronal lineage cells from stem cells and a therapy of brain injury and disease.

Effects and mechanism of astragalus polysaccharide on wound healing of deep partial-thickness burns in rats

Objective: To investigate the effects and mechanism of astragalus polysaccharide (APS) on wound healing of deep partial-thickness burns in rats. Methods: The experimental study method was used. Fifty 7-week-old male Sprague-Dawley rats were divided into normal group, simple burn group, APS group, inhibitor group, and inhibitor+APS group according to the random number table, with 10 rats in each group. Except for normal group, rats in the other 4 groups were inflicted with a deep partial-thickness burn wound on the back. Rats in normal group and simple burn group were intraperitoneally injected with normal saline, and rats in the other three groups were injected with APS and/or integrin-linked kinase (ILK) inhibitor, respectively. After 7 days of injection, the wound healing rate of rats with burns in the four groups was calculated, and the serum content of interferon-γ, interleukin-2 (IL-2), and tumor necrosis factor α (TNF-α) in rats in 5 groups was determined by enzyme-linked immunosorbent assay (ELISA). The normal skin tissue of rats in normal group and wound tissue of rats with burns in the four groups were taken, the water content was determined and the water ratio was calculated, the content of interferon-γ, IL-2, and TNF-α was detected by ELISA, the mRNA expressions of epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and ILK were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction, and the protein expressions of ILK, protein kinase B (Akt), phosphorylated Akt (p-Akt), glycogen synthetic kinase-3β (GSK-3β), and phosphorylated GSK-3β (p-GSK-3β) were detected by Western blotting. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: After 7 days of injection, the wound healing rate of rats in APS group was (67±5)%, which was significantly higher than (52±4)% in simple burn group and (59±5)% in inhibitor+APS group (with all the P values <0.05). The wound healing rate of rats in inhibitor+APS group was significantly higher than (48±4)% in inhibitor group (P<0.05). After 7 days of injection, compared with those in serum or normal skin tissue of rats in normal group, the serum content of interferon-γ, TNF-α, IL-2 and the water ratio of wound tissue of rats in simple burn group were significantly increased (P<0.05); compared with those in APS group, the serum content of interferon-γ, TNF-α, IL-2 and the water ratio of wound tissue of rats in simple burn group and inhibitor+APS group were significantly increased (P<0.05); compared with those in inhibitor group, the serum content of interferon-γ, TNF-α, IL-2 and the water ratio of wound tissue of rats in inhibitor+APS group were significantly decreased (P<0.05). After 7 days of injection, compared with that in normal skin tissue of rats in normal group, the content of interferon-γ, TNF-α, and IL-2 in wound tissue of rats in simple burn group was significantly increased (P<0.05); compared with that in APS group, the content of interferon-γ, TNF-α, and IL-2 in wound tissue of rats in simple burn group and inhibitor+APS group was significantly increased (P<0.05); compared with that in inhibitor group, the content of interferon-γ, TNF-α, and IL-2 in wound tissue of rats in inhibitor+APS group was significantly decreased (P<0.05). After 7 days of injection, compared with those in normal skin tissue of rats in normal group, the mRNA expressions of EGF, bFGF, ILK and protein expressions of ILK, p-Akt, p-GSK-3β in wound tissue of rats in simple burn group were significantly increased (P<0.05); compared with those in APS group, the mRNA expressions of EGF, bFGF, ILK and protein expressions of ILK, p-Akt, p-GSK-3β in wound tissue of rats in simple burn group and inhibitor+APS group were significantly decreased (P<0.05); compared with those in inhibitor group, the mRNA expressions of EGF, bFGF, ILK and protein expressions of ILK, p-Akt, p-GSK-3β in wound tissue of rats in inhibitor+APS group were significantly increased (P<0.05). There were no statistically significant differences in the protein expressions of Akt and GSK-3β in normal skin tissue of rats in normal group and wound tissue of rats with burns in the four groups (P>0.05). Conclusions: APS can alleviate systemic and local inflammation, alleviate tissue edema, and promote the expressions of healing factors in rats with deep partial-thickness burns, thus to promote the wound healing, possibly by activating ILK/Akt/GSK-3β signaling pathway.

Ultrasound-Triggered Microbubbles: Novel Targeted Core-Shell for the Treatment of Myocardial Infarction Disease.

Myocardial infarction (MI) is known as a main cardiovascular disease that leads to extensive cell death by destroying vasculature in the affected cardiac muscle. The development of ultrasound-mediated microbubble destruction has inspired extensive interest in myocardial infarction therapeutics, targeted delivery of drugs, and biomedical imaging. In this work, we describe a novel therapeutic ultrasound system for the targeted delivery of biocompatible microstructures containing basic fibroblast growth factor (bFGF) to the MI region. The microspheres were fabricated using poly(lactic-co-glycolic acid)-heparin-polyethylene glycol- cyclic arginine-glycine-aspartate-platelet (PLGA-HP-PEG-cRGD-platelet). The micrometer-sized core-shell particles consisting of a perfluorohexane (PFH)-core and a PLGA-HP-PEG-cRGD-platelet-shell were prepared using microfluidics. These particles responded adequately to ultrasound irradiation by triggering the vaporization and phase transition of PFH from liquid to gas in order to achieve microbubbles. Ultrasound imaging, encapsulation efficiency cytotoxicity, and cellular uptake of bFGF-MSs were evaluated using human umbilical vein endothelial cells (HUVECs) in vitro. In vivo imaging demonstrated effective accumulation of platelet- microspheres injected into the ischemic myocardium region. The results revealed the potential use of bFGF-loaded microbubbles as a noninvasive and effective carrier for MI therapy.

Absorbable 3D-printed pancreaticojejunostomy device with a dual-layer drug coating for the prevention of postoperative local recurrence of pancreatic cancer

The high local recurrence rate of pancreatic cancer after surgery is one of the important risk factors affecting patient survival. The traditionally used silicone tube stent is not only complicated to operate but also lacks antitumor properties. The purpose of this study was to develop a dual-layer drug-coated pancreaticojejunostomy device. The coating consisted of two layers, an outer basic fibroblast growth factor (bFGF) coating layer and an inner nanoparticle albumin-bound paclitaxel (nab-PTX) coating layer with chitosan as the drug-carrying medium. Due to the diffusion barrier from the outer coating, the release of nab-PTX from the inner layer was delayed and slowed down. We studied the degradation rates, mechanical properties, surface morphologies, drug release kinetics, promoting the growth of fibroblasts and antitumor properties of the coated stents. It was found that 100 ng of bFGF and 50 µg of nab-PTX were suitable drug concentrations that can effectively promote the growth of fibroblasts and inhibit pancreatic cancer cells. The results also confirmed that the dual-layer drug-coated pancreaticojejunostomy device showed good antitumor activity both in vitro and in vivo without obvious systemic toxicity. In addition, the device has a suitable degradation rate. In conclusion, this biodegradable dual-layer drug-coated pancreaticojejunostomy device can potentially inhibit the local recurrence of pancreatic cancer after surgery and promote the healing of pancreaticointestinal anastomosis. This device has great potential to treat pancreatic cancer in the future.

Hydrogel‐Based Artificial Mucosa Restores Local Immune and Microbial Homeostasis for Treating Ulcerative Colitis

AbstractUlcerative colitis (UC) is a common inflammatory bowel disease driven by the dyshomeostasis of intestinal immune system and microbiota, but its treatment options are limited due to impaired epithelial barrier integrity and function. Herein, a multifunctional biomimetic hydrogel is developed as artificial colonic mucosa, which can readily establish a bioadhesive barrier at the ulcer site and restore local immune and microbial homeostasis to exert potent anti‐inflammatory effect. The hydrogel framework is generated through the thrombin‐mediated activation and polymerization of fibrinogen that resembles natural blood coagulation mechanism. During this process, the antibacterial agent Ag+ is used for the crosslinking between the generated fibrin units and dopamine/thiol‐modified hyaluronic acid biopolymers via Ag+‐thiol coordination to convey enhanced bioadhesiveness, while the interconnected porous network is employed to encapsulate basic fibroblast growth factor (bFGF) and alanyl‐glutamine (ALG) for mucosa regeneration. The hydrogel stably adheres to the ulcer site to protect and repair the damaged epithelium and establishes an anti‐inflammatory microenvironment by inducing locoregional M1‐to‐M2 macrophage repolarization while eliminating harmful gut flora, which can act in a cooperative manner to substantially alleviate UC symptoms. The biomimetic hydrogel here presents a promising approach for effective UC therapy in the clinics.

Overactivation of Norepinephrine-β2-Adrenergic Receptor Axis Promotes Corneal Neovascularization.

To investigate the role of the sympathetic nervous system in corneal neovascularization (CNV) and to identify the downstream pathway involved in this regulation. Three types of CNV models were constructed with C57BL/6J mice, including the alkali burn model, suture model, and basic fibroblast growth factor (bFGF) corneal micropocket model. Subconjunctival injection of the sympathetic neurotransmitter norepinephrine (NE) was administered in these three models. Control mice received injections of water of the same volume. The corneal CNV was detected using slit-lamp microscopy and immunostaining with CD31, and the results were quantified by ImageJ. The expression of β2-adrenergic receptor (β2-AR) was stained with mouse corneas and human umbilical vein endothelial cells (HUVECs). Furthermore, the anti-CNV effects of β2-AR antagonist ICI-118,551 (ICI) were examined with HUVEC tube formation assay and with a bFGF micropocket model. Additionally, partial β2-AR knockdown mice (Adrb2+/-) were used to establish the bFGF micropocket model, and the corneal CNV size was quantified based on the slit-lamp images and vessel staining. Sympathetic nerves invaded the cornea in the suture CNV model. The NE receptor β2-AR was highly expressed in corneal epithelium and blood vessels. The addition of NE significantly promoted corneal angiogenesis, whereas ICI effectively inhibited CNV invasion and HUVEC tube formation. Adrb2 knockdown significantly reduced the cornea area occupied by CNV. Our study found that sympathetic nerves grow into the cornea in conjunction with newly formed vessels. The addition of the sympathetic neurotransmitter NE and activation of its downstream receptor β2-AR promoted CNV. Targeting β2-AR could potentially be used as an anti-CNV strategy.

Study on in vitro differentiation of human adenoid-derived mesenchymal stem cells into olfactory sensory neurons

Objective: To investigate the feasibility of isolation and culture of human adenoid-derived mesenchymal stem cells (aMSCs) in vitro, and to observe the differentiation of aMSCs into olfactory sensory neurons. Methods: Adenoid tissues surgically removed from children with adenoid hypertrophy in the Second Xiangya Hospital of Central South University from September to November of 2020 were collected. The adenoid tissues were digested and isolated by trypsin and then cultured with adhesion method. The expressions of cell surface antigens CD45, CD73 and CD90 on aMSCs of P5 generation were tested by flow cytometry, and the ability of osteogenic and adipogenic induction were used to identify cell differentiation ability. Then, aMSCs were induced into differentiation by retinoic acid (RA), sonic hedgehog (SHH), basic fibroblast growth factor (bFGF), RA+SHH, RA+bFGF, SHH+bFGF and RA+SHH+bFGF, respectively. The morphology of differentiated cells was observed under inverted microscope. The expression of β-tubulin 3, which was the specific marker of sensory neuron, the expressions of growth associated protein-43 (GAP43) and olfactory maker protein (OMP), which were the specific markers of olfactory sensory neuron, were detected by immunofluorescence antibody assay. The expression intensities were compared by Chi-square test of four-grid table data. Results: aMSCs were successively isolated and cultured from human adenoid tissues. P0 cells generation had good adhesion and proliferation performance. P2 cells were basically purified. P5 cells expressed CD73 and CD90 with the purity of 99.3% and 99.75% respectively, without CD45 expression. P5 cells had a good ability of osteogenic differentiation and adipogenic differentiation. Neuron-like morphology and expression of β-tubulin 3 were found in differentiated cells after induced by RA, SHH, or bFGF, respectively. An induction of expression of GAP43 was found in differentiated cells of bFGF+SHH group and RA+SHH+bFGF group, without expression of OMP of each group. The intensity of GAP43 expression of RA+SHH+bFGF group was stronger than that of bFGF+SHH group (χ2=17.48, P<0.005). Conclusions: aMSCs can be cultured from human adenoid tissues, with the stably passaged and good differentiation ability. As a new population of mesenchymal stem cells, aMSCs have the neuroregenerative properties and could differentiate into immature olfactory sensory neurons under the induction of RA+SHH+bFGF in vitro.

Injectable TG-linked recombinant human collagen hydrogel loaded with bFGF for rat cranial defect repair

The basic fibroblast growth factor (bFGF) plays a significant role in promoting the process of bone repair, but bFGF cannot keep its biological activity stable under normal physiological conditions. Therefore, the development of better biomaterials to carry bFGF remains a challenge for bone repair and regeneration. Here we designed a novel recombinant human collagen (rhCol), which could be cross-linked by transglutaminase (TG) and loaded bFGF to prepare rhCol/bFGF hydrogels. The rhCol hydrogel possessed a porous structure and good mechanical properties. The assays, including cell proliferation, migration, and adhesion assay, were performed to evaluate the biocompatibility of rhCol/bFGF and the results demonstrated that the rhCol/bFGF promoted cell proliferation, migration and adhesion. The rhCol/bFGF hydrogel degraded and released bFGF controllably, enhancing utilization rate of bFGF and allowing osteoinductive activity. The results of RT-qPCR and immunofluorescence staining also proved that rhCol/bFGF promoted expression of bone-related proteins. The rhCol/bFGF hydrogels were applied in the cranial defect in rats and the results confirmed that it accelerates bone defect repair. In conclusion, rhCol/bFGF hydrogel has excellent biomechanical properties and can continuously release bFGF to promote bone regeneration, suggesting that rhCol/bFGF hydrogel is a potential scaffold in clinic application.

Prevention and Repair of Ultraviolet B-Induced Skin Damage in Hairless Mice via Transdermal Delivery of Growth Factors Immobilized in a Gel-in-Oil Nanoemulsion.

Ultraviolet (UV) radiation from the sun or artificial sources is one of the primary causes of skin damage, including sunburns, tanning, erythema, and skin cancer. Among the three different types of UV rays, UVB rays have a medium wavelength that can penetrate the epidermal layer of the skin, resulting in sunburn, suntan, blistering, and melanoma in case of chronic exposure. This study aimed to evaluate the preventive and therapeutic effects of a gel-in-oil nanogel dispersion (G/O-NGD) as a transdermal delivery biomolecular carrier for skin damage caused by UVB light. The efficacy of this carrier against UVB-induced skin damage was investigated in vivo by delivering different growth factors (GFs) encapsulated in a G/O-NGD. Artificial UVB light was used to induce skin damage in nude mice, followed by the transdermal application of five GF [vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), transforming growth factor (TGF)-1, and insulin-like growth factor (IGF)-α]-immobilized G/O-NGD. Among these GFs, VEGF and bFGF promoted angiogenesis, while EGF, TGF-1, and IGF-α promoted the repair and regeneration of damaged cells. The results showed that G/O-NGD was superior to heparin-immobilized G/O-NGD in reducing UVB-induced skin damage, such as erythema, epidermal water reduction, inflammation, and dermis thickening. In addition, G/O-NGD could prevent and treat abnormal follicle proliferation caused by UVB rays and exhibited potential to repair lipid glands. Overall, our results demonstrate the potential of G/O-NGDs for the treatment of UVB-induced skin damage.

The stereological, immunohistological, and gene expression studies in an infected ischemic wound in diabetic rats treated by human adipose-derived stem cells and photobiomodulation.

We investigated the impacts of photobiomodulation (PBM) and human allogeneic adipose-derived stem cells (ha-ADS) together and or alone applications on the stereological parameters, immunohistochemical characterizing of M1 and M2 macrophages, and mRNA levels of hypoxia-inducible factor (HIF-1α), basic fibroblast growth factor (bFGF), vascular endothelial growth factor-A (VEGF-A) and stromal cell-derived factor-1α (SDF-1α) on inflammation (day 4) and proliferation phases (day 8) of repairing tissues in an infected delayed healing and ischemic wound model (IDHIWM) in type 1 diabetic (DM1) rats. DM1 was created in 48 rats and an IDHIWM was made in all of them, and they were distributed into 4 groups. Group1 = control rats with no treatment. Group2 = rats received (10 × 100000ha-ADS). Group3 = rats exposed to PBM (890nm, 80Hz, 3.46J/cm2). Group4 = rats received both PBM and ha-ADS. On day 8, there were significantly higher neutrophils in the control group than in other groups (p < 0.01). There were substantially higher macrophages in the PBM + ha-ADS group than in other groups on days 4 and 8 (p < 0.001). Granulation tissue volume, on both days 4 and 8, was meaningfully greater in all treatment groups than in the control group (all, p = 0.000). Results of M1 and M2 macrophage counts of repairing tissue in the entiretreatmentgroups were considered preferable to those in the control group (p < 0.05). Regarding stereological and macrophage phenotyping, the results of the PBM + ha-ADS group were better than the ha-ADS and PBM groups. Results of the tested gene expression of repairing tissue on inflammation and proliferation steps in PBM and PBM + ha-ADS groups were meaningfully better than the control and ha-ADS groups (p < 0.05). We showed that PBM, ha-ADS, and PBM plus ha-ADS, hastened the proliferation step of healing in an IDHIWM in rats with DM1 by regulation of the inflammatory reaction, macrophage phenotyping, and augmented granulation tissue formation. In addition PBM and PBM plus ha-ADS protocols hastened and increased mRNA levels of HIF-1α, bFGF, SDF-1α, and VEGF-A. Totally, in terms of stereological and immuno-histological tests, and also gene expression HIF-1α and VEGF-A, the results of PBM + ha-ADS were superior (additive) to PBM, and ha-ADS alone treatments.