Effect of simultaneous and sequential use of TGF-β1 and TGF-β3 with FGF-2 on teno/ligamentogenic differentiation of periodontal ligament stem cells

OBJECTIVE

The periodontal ligament is a crucial part of the periodontium, and its regeneration is challenging. This study compares the effect of simultaneous and sequential use of FGF-2 and TGF-β1 with FGF-2 and TGF-β3 on the periodontal ligament stem cells (PDLSCs) teno/ligamentogenic differentiation.

DESIGN

This study comprises ten different groups. A control group with only PDLSCs; FGF-2 group containing PDLSCs with a medium culture supplemented with FGF-2 (50 ng/mL). In other experimental groups, different concentrations (5 ng/mL or 10 ng/mL) of TGF-β1&-β3 simultaneously or sequentially were combined with FGF-2 on the cultured PDLSCs. TGF-β was added to the medium after day 3 in the sequential groups. Methyl Thiazolyl Tetrazolium (MTT) assay on days 3, 5, and 7 and Quantitative Real-time Polymerase Chain Reaction (RT-qPCR) analysis after day 7 were conducted to investigate PLAP1, SCX, and COL3A1, RUNX2 genes. All experiments were conducted in a triplicate. The One-way and Two-way ANOVA with Tukey post hoc were utilized to analyze the results of the MTT and RT-qPCR tests, respectively. A p-value less than 0.05 is considered significant.

RESULTS

The proliferation of cells on days 3, 5, and 7 was not significantly different among different experimental groups (P > 0.05). A higher expression of the PLAP1, SCX, and COL3A1 have been seen in groups with sequential use of growth factors; among these groups, the group using 5 ng/mL of TGF-β3 led other groups with the most amount of significant upregulation in PLAP1(17.69 ± 1.11 fold; P < 0.0001), SCX (5.71 ± 0.38 fold; P < 0.0001), and COL1A3 (6.35 ± 0.39 fold; P < 0.0001) expression, compared to the control group. The expression of the RUNX2 decreased in all groups compared to the control group; this reduction was more in groups with sequential use of growth factors.

CONCLUSION

The sequential use of growth factors can be more effective than simultaneous use in teno/ligamentogenic differentiation of PDLSCs. Moreover, treatment with 5 ng/mL TGF-β3 after FGF-2 was more effective than TGF-β1.

Appropriate dosage, timing, and site of intramuscular injections of brain-derived neurotrophic factor (BDNF) promote motor recovery after facial nerve injury in rats

INTRODUCTION/AIMS

Daily intramuscular injections of fibroblast growth factor 2 (FGF2) but not of brain-derived neurotrophic factor (BDNF) significantly improve whisking behavior and mono-innervation of the rat levator labii superioris (LLS) muscle 56 days after buccal nerve transection and suture (buccal-buccal anastomosis, BBA). We explored the dose-response of BDNF, FGF2, and insulin growth factor 2 (IGF2) on the same parameters, asking whether higher doses of BDNF would promote recovery.

METHODS

After BBA, growth factors were injected (30 μL volume) daily into the LLS muscle over 14, 28, or 56 days. At 56 days, video-based motion analysis of vibrissal whisking was performed and the extent of mono- and poly-reinnervation of the reinnervated neuromuscular junctions (NMJs) of the muscle determined with immunostaining of the nerve with β-tubulin and histochemical staining of the endplates with Alexa Fluor 488-conjugated α-bungarotoxin.

RESULTS

The dose-response curve demonstrated significantly higher whisking amplitudes and corresponding increased mono-innervation of the NMJ in the reinnervated LLS muscle at concentrations of 20-30 μg/mL BDNF administered daily for 14-28 days after BBA surgery. In contrast, high doses of IGF2 and FGF2, or doses of 20 and 40 μg/mL of BDNF administered for 14-56 days had no effect on either whisking behavior or in reducing poly-reinnervation of endplates in the muscle.

DISCUSSION

These data suggest that the re-establishment of mono-innervation of whiskerpad muscles and the improved motor function by injections of BDNF into the paralyzed vibrissal musculature after facial nerve injury have translation potential and promote clinical application.

Paradoxical cancer cell proliferation after FGFR inhibition through decreased p21 signaling in FGFR1-amplified breast cancer cells

Fibroblast growth factors (FGFs) control various cellular functions through fibroblast growth factor receptor (FGFR) activation, including proliferation, differentiation, migration, and survival. FGFR amplification in ER + breast cancer patients correlate with poor prognosis, and FGFR inhibitors are currently being tested in clinical trials. By comparing three-dimensional spheroid growth of ER + breast cancer cells with and without FGFR1 amplification, our research discovered that FGF2 treatment can paradoxically decrease proliferation in cells with FGFR1 amplification or overexpression. In contrast, FGF2 treatment in cells without FGFR1 amplification promotes classical FGFR proliferative signaling through the MAPK cascade. The growth inhibitory effect of FGF2 in FGFR1 amplified cells aligned with an increase in p21, a cell cycle inhibitor that hinders the G1 to S phase transition in the cell cycle. Additionally, FGF2 addition in FGFR1 amplified cells activated JAK-STAT signaling and promoted a stem cell-like state. FGF2-induced paradoxical effects were reversed by inhibiting p21 or the JAK-STAT pathway and with pan-FGFR inhibitors. Analysis of patient ER + breast tumor transcriptomes from the TCGA and METABRIC datasets demonstrated a strong positive association between expression of FGF2 and stemness signatures, which was further enhanced in tumors with high FGFR1 expression. Overall, our findings reveal a divergence in FGFR signaling, transitioning from a proliferative to stemness state driven by activation of JAK-STAT signaling and modulation of p21 levels. Activation of these divergent signaling pathways in FGFR amplified cancer cells and paradoxical growth effects highlight a challenge in the use of FGFR inhibitors in cancer treatment.

Impact of media supplements FGF2, LIF and IGF1 on the genome activity of porcine embryos produced in vitro

In this article, we focused on the impact of precisely chemically modified FLI maturation medium enriched with fibroblast growth factor 2 (FGF2), leukemia inhibitory factor (LIF), insulin-like growth factor 1 (IGF1), and polyvinyl alcohol (PVA) and its potential to improve the efficiency of in vitro production of porcine embryos. We hypothesized that enhancing the composition of the maturation medium could result in an elevated production of embryos in vitro and can affect EGA. FLI medium resulted in a significantly higher rate of oocyte blastocyst maturation and formation compared to the control DMEM medium. In addition, immunocytochemical labelling confirmed the detection of UBF in 4-cell FLI parthenogenic embryos, suggesting similarities with natural embryo development. Through RNAseq analysis, upregulated genes present in 4-cell FLI embryos were found to play key roles in important biological processes such as cell proliferation, cell differentiation, and transcriptional regulation. Based on our findings, we demonstrated the positive influence of FLI medium in the evaluation of in vitro embryo production, EGA detection, transcriptomic and proteomic profile, which was confirmed by the positive activation of the embryonal genome in the 4-cell stage of parthenogenetically activated embryos.

Embryonic stem cells overexpressing high molecular weight FGF2 isoform enhance recovery of pre-ganglionic spinal root lesion in combination with fibrin biopolymer mediated root repair

BACKGROUND

Spinal ventral root avulsion results in massive motoneuron degeneration with poor prognosis and high costs. In this study, we compared different isoforms of basic fibroblast growth factor 2 (FGF2), overexpressed in stably transfected Human embryonic stem cells (hESCs), following motor root avulsion and repair with a heterologous fibrin biopolymer (HFB).

METHODS

In the present work, hESCs bioengineered to overexpress 18, 23, and 31 kD isoforms of FGF2, were used in combination with reimplantation of the avulsed roots using HFB. Statistical analysis was conducted using GraphPad Prism software with one-way or two-way ANOVA, followed by Tukey's or Dunnett's multiple comparison tests. Significance was set at *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001.

RESULTS

For the first set of experiments, rats underwent avulsion of the ventral roots with local administration of HFB and engraftment of hESCs expressing the above-mentioned FGF2 isoforms. Analysis of motoneuron survival, glial reaction, and synaptic coverage, two weeks after the lesion, indicated that therapy with hESCs overexpressing 31 kD FGF2 was the most effective. Consequently, the second set of experiments was performed with that isoform, so that ventral root avulsion was followed by direct spinal cord reimplantation. Motoneuron survival, glial reaction, synaptic coverage, and gene expression were analyzed 2 weeks post-lesion; while the functional recovery was evaluated by the walking track test and von Frey test for 12 weeks. We showed that engraftment of hESCs led to significant neuroprotection, coupled with immunomodulation, attenuation of astrogliosis, and preservation of inputs to the rescued motoneurons. Behaviorally, the 31 kD FGF2 - hESC therapy enhanced both motor and sensory recovery.

CONCLUSION

Transgenic hESCs were an effective delivery platform for neurotrophic factors, rescuing axotomized motoneurons and modulating glial response after proximal spinal cord root injury, while the 31 kD isoform of FGF2 showed superior regenerative properties over other isoforms in addition to the significant functional recovery.

Meiotic and developmental competence of growing pig oocytes derived from small antral follicles is enhanced in culture medium containing FGF2, LIF, and IGF1 (FLI medium)

BACKGROUND

Oocytes of large animal species isolated from small ovarian follicles (< 2 mm) are less competent to support early embryonic development after in vitro maturation and fertilization than their counterparts isolated from medium-sized and preovulatory follicles. This study aimed to assess the effect of a new maturation medium containing FGF2, LIF, and IGF1 (FLI medium) on the meiotic and developmental competence of pig cumulus-oocytes complexes (COCs) derived from the small and medium-sized follicles.

METHODS

The growing oocytes were isolated from 1 to 2 (small follicle; SF) and the fully-grown ones from 3 to 6 (large follicle; LF) mm follicles and matured in a control M199 medium with gonadotropins and EGF and the FLI medium enriched by the triplet of growth factors. The matured oocytes were parthenogenetically activated and cultured to the blastocyst stage. Chromatin configuration before and during the culture and MAP kinase activity were assessed in the oocytes. Finally, the expression of cumulus cell genes previously identified as markers of oocyte quality was assessed.

RESULTS

The maturation and blastocyst rates of oocytes gained from LF were significantly higher than that from SF in the control medium. In contrast, similar proportions of oocytes from LF and SF completed meiosis and developed to blastocysts when cultured in FLI. Most of the oocytes freshly isolated from SF possessed germinal vesicles with fine filaments of chromatin (GV0) or chromatin surrounding the nucleolus (GVI; 30%); the oocytes from LF were mainly in GVI (or GVII) exhibiting a few small lumps of chromatin beneath the nuclear membrane. When cultured in the FLI medium for 16 h, an acceleration of the course of maturation in oocytes both from SF and LF compared to the control medium was observed and a remarkable synchrony in the course of chromatin remodeling was noticed in oocytes from SF and LF.

CONCLUSIONS

This work demonstrates that the enrichment of culture medium by FGF2, LIF, and IGF1 can enhance the meiotic and developmental competence of not only fully-grown, but also growing pig oocytes and significantly thus expanding the number of oocytes available for various assisted reproductive technology applications.

The optimized priming effect of FGF-1 and FGF-2 enhances preadipocyte lineage commitment in human adipose-derived mesenchymal stem cells

The cell-assisted lipotransfer technique, integrating adipose-derived mesenchymal stem cells (ADMSCs), has transformed lipofilling, enhancing fat graft viability. However, the multipotent nature of ADMSCs poses challenges. To improve safety and graft vitality and to reduce unwanted lineage differentiation, this study refines the methodology by priming ADMSCs into preadipocytes-unipotent, self-renewing cells. We explored the impact of fibroblast growth factor-1 (FGF-1), fibroblast growth factor-2 (FGF-2), and epidermal growth factor (EGF), either alone or in combination, on primary human ADMSCs during the proliferative phase. FGF-2 emerged as a robust stimulator of cell proliferation, preserving stemness markers, especially when combined with EGF. Conversely, FGF-1, while not significantly affecting cell growth, influenced cell morphology, transitioning cells to a rounded shape with reduced CD34 expression. Furthermore, co-priming with FGF-1 and FGF-2 enhanced adipogenic potential, limiting osteogenic and chondrogenic tendencies, and possibly promoting preadipocyte commitment. These preadipocytes exhibited unique features: rounded morphology, reduced CD34, decreased preadipocyte factor 1 (Pref-1), and elevated C/EBPα and PPARγ, alongside sustained stemness markers (CD73, CD90, CD105). Mechanistically, FGF-1 and FGF-2 activated key adipogenic transcription factors-C/EBPα and PPARγ-while inhibiting GATA3 and Notch3, which are adipogenesis inhibitors. These findings hold the potential to advance innovative strategies for ADMSC-mediated lipofilling procedures.

Fibroblast Growth Factor Soaked Collagen Membrane Shows No Biomechanical or Histological Advantages in the Treatment of Chronic Rotator Cuff Tears in a Rabbit Model

PURPOSE

To investigate the histological and biomechanical effects of a fibroblast growth factor (FGF-2)-soaked collagen membrane used to treat a full-thickness chronic rotator cuff (RC) rupture in a rabbit model.

METHODS

Forty-eight shoulders from 24 rabbits were used. At the beginning of the procedure, 8 rabbits were killed to assess the control group (Group IT) with intact tendons. To establish a chronic RC tear model, a full-thickness subscapularis tear was created on both shoulders of the remaining 16 rabbits and left for 3 months. The transosseous mattress suture technique was used to repair tears in the left shoulder (Group R). The tears in the right shoulder (Group CM) were treated using the same approach, with an FGF-soaked collagen membrane inserted and sutured over the repair site. Three months after the procedure, all rabbits were killed. Biomechanical testing was performed on the tendons to determine failure load, linear stiffness, elongation intervals, and displacement. Histologically, the modified Watkins score was used to evaluate tendon-bone healing.

RESULTS

There was no significant difference among the three groups in terms of failure load, displacement, linear stiffness, and elongation (P > .05). The total modified Watkins score was not affected by applying the FGF-soaked collagen membrane to the repair site (P > .05). Fibrocytes, parallel cells, large-diameter fibers, and the total modified Watkins score were significantly lower in both repair groups when compared to the intact tendon group (P < .05).

CONCLUSIONS

In addition to tendon repair, FGF-2 soaked collagen membrane -application at the repair site provides neither biomechanical nor histological advantages in the treatment of chronic RC tears.

CLINICAL RELEVANCE

FGF-soaked collagen membrane augmentation provides no impact on the chronic RC tear healing tissue. The need to investigate alternative methods that may have a positive effect on healing in chronic RC repairs continues.

Inhibition of valve mesenchymal stromal cell calcium deposition by bFGF through alternative polyadenylation regulation of the CAT gene

OBJECTIVE

Calcific aortic valve disease (CAVD) is the leading cause of angina, heart failure, and death from aortic stenosis. However, the molecular mechanisms of its progression, especially the complex disease-related transcriptional regulatory mechanisms, remain to be further elucidated.

METHODS

This study used porcine valvular interstitial cells (PVIC) as a model. We used osteogenic induced medium (OIM) to induce calcium deposition in PVICs to calcify them, followed by basic fibroblast growth factor (bFGF) treatment to inhibit calcium deposition. Transcriptome sequencing was used to study the mRNA expression profile of PVICs and its related transcriptional regulation. We used DaPars to further examine alternative polyadenylation (APA) between different treatment groups.

RESULTS

We successfully induced calcium deposition of PVICs through OIM. Subsequently, mRNA-seq was used to identify differentially expressed mRNAs for three different treatments: control, OIM-induced and OIM-induced bFGF treatment. Global APA events were identified in the OIM and bFGF treatment groups by bioinformatics analysis. Finally, it was discovered and proven that catalase (CAT) is one of the potential targets of bFGF-induced APA regulation.

CONCLUSION

We described a global APA change in a calcium deposition model related to CAVD. We revealed that transcriptional regulation of the CAT gene may contribute to bFGF-induced calcium deposition inhibition.

Anti-inflammatory and healing effect of the polysaccharidic extract of Opuntia ficus-indica cladodes in cutaneous excisional wounds in rats

This study aimed to investigate the anti-inflammatory and wound healing effects of the polysaccharide extract from Opuntia ficus-indica cladodes (TPL-Ofi) using a rat cutaneous wound model. After anaesthesia, four 7-mm-diameter dorsal wounds per animal (n = 6/group for each experimental day of evaluation) were created in female Wistar rats using a surgical punch. The animals were treated topically twice daily with TPL-Ofi (0.01-1%; treated group) or sterile saline (control group) for a period of 21 days. Ulcerated tissue was collected for analysis of histological parameters (inflammation score, number of polymorphonuclear, mononuclear, fibroblast/myofibroblasts and blood vessels), immunohistochemical (fibroblast growth factor 2 [FGF-2]) and oxidative stress markers (myeloperoxidase [MPO] and glutathione [GSH]). After 21 days of treatment, body weight, net organ weight and plasma biochemical levels were measured. TPL-Ofi, containing a total carbohydrate content of 65.5% and uronic acid at 2.8%, reduced oedema on the second day and increased the nociceptive threshold on the second and third days. TPL-Ofi reduced mononuclear infiltrate on the second and MPO activity on the fifth day. TPL-Ofi increased GSH levels on the second day, as well as fibroblast/myofibroblasts counts, neoangiogenesis and FGF-2 levels on the fifth and seventh days. No changes were observed in body weight, net organ weight or toxicology assessment. Topical application of TPL-Ofi exhibited anti-inflammatory and antinociceptive effects, ultimately improving wound healing in cutaneous wounds.

Terminus-Selective Covalent Immobilization of Heparin on a Thermoresponsive Surface Using Click Chemistry for Efficient Binding of Basic Fibroblast Growth Factor

Cell therapy using endothelial cells (ECs) has great potential for the treatment of congenital disorders, such as hemophilia A. Cell sheet technology utilizing a thermoresponsive culture dish is a promising approach to efficiently transplant donor cells. In this study, a new method to prepare terminus-selective heparin-immobilized thermoresponsive culture surfaces is developed to facilitate the preparation of EC sheets. Alkynes are introduced to the reducing terminus of heparin via reductive amination. Cu-catalyzed azide-alkyne cycloaddition (CuAAC) facilitates efficient immobilization of the terminus of heparin on a thermoresponsive surface, resulting in a higher amount of immobilized heparin while preserving its function. Heparin-immobilized thermoresponsive surfaces prepared using CuAAC exhibit good adhesion to human endothelial colony-forming cells (ECFCs). In addition, upon further binding to basic fibroblast growth factor (bFGF) on heparin-immobilized surfaces, increased proliferation of ECFCs on the surface is observed. The confluent ECFC monolayer cultured on bFGF-bound heparin-immobilized thermoresponsive surfaces exhibits relatively high fibronectin accumulation and cell number and detaches at 22 °C while maintaining the sheet-like structure. Because heparin has an affinity for several types of bioactive molecules, the proposed method can be applied to facilitate efficient cultures and sheet formations of various cell types.

Applications of Plant-Made Fibroblast Growth Factor for Human Pluripotent Stem Cells

Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) hold great potential in regenerative medicine. These cells can be expanded indefinitely in theory and are able to differentiate into different types of cells for cell therapies, drug screening, and basic biology studies. The reliable and effective propagation of hESCs and hiPSCs is important for their downstream applications. Basic fibroblast growth factor (bFGF) is critical to hESCs and hiPSCs for maintaining their pluripotency. Plant-produced growth factors are safe to use without potential contamination of infectious viruses and are less expensive to produce. In this study, we used rice cell-made basic fibroblast growth factor (RbFGF) to propagate hESCs and hiPSCs for at least eight passages. Both hESCs and hiPSCs cultured with RbFGF not only maintained the morphology but also the specific expression (OCT4, SSEA4, SOX2, and TRA-1-60) of PSCs, similar to those cultured with the commercial Escherichia coli-produced bFGF. Furthermore, both gene chip-based PluriTest and TaqMan hPSC Scorecard pluripotency analysis demonstrated the pluripotent expression profile of the hESCs cultured with RbFGF. In vitro trilineage assays further showed that these hESCs and hiPSCs cultured on RbFGF were capable of giving rise to cell derivatives of ectoderm, mesoderm, and endoderm, further demonstrating their pluripotency. Finally, chromosome stability was also maintained in hESCs cultured with RbFGF as demonstrated by normal karyotypes. This study suggests broad applications for plant-made growth factors in stem cell culture and regenerative medicine.

Fluoride-Incorporated Apatite Coating on Collagen Sponge as a Carrier for Basic Fibroblast Growth Factor

Coating layers consisting of a crystalline apatite matrix with immobilized basic fibroblast growth factor (bFGF) can release bFGF, thereby enhancing bone regeneration depending on their bFGF content. We hypothesized that the incorporation of fluoride ions into apatite crystals would enable the tailored release of bFGF from the coating layer depending on the layer's fluoride content. In the present study, coating layers consisting of fluoride-incorporated apatite (FAp) crystals with immobilized bFGF were coated on a porous collagen sponge by a precursor-assisted biomimetic process using supersaturated calcium phosphate solutions with various fluoride concentrations. The fluoride content in the coating layer increased with the increasing fluoride concentration of the supersaturated solution. The increased fluoride content in the coating layer reduced its solubility and suppressed the burst release of bFGF from the coated sponge into a physiological salt solution. The bFGF release was caused by the partial dissolution of the coating layer and, thus, accompanied by the fluoride release. The concentrations of released bFGF and fluoride were controlled within the estimated effective ranges in enhancing bone regeneration. These findings provide useful design guidelines for the construction of a mineralized, bFGF-releasing collagen scaffold that would be beneficial for bone tissue engineering, although further in vitro and in vivo studies are warranted.

BFGF attenuates aortic valvular interstitial cell calcification by inhibiting endoplasmic reticulum stress-mediated apoptosis

The potential protective effect of basic fibroblast growth factor (BFGF) on the cardiovascular system has been proposed previously, however, its effect on calcific aortic valve disease (CAVD) and underlying mechanisms have not been elucidated. The valvular interstitial cell (VIC) were isolated from porcine aortic valve leaflets. To investigate the effect of BFGF on osteogenic differentiation of VIC, the osteogenic induced medium (OIM) and BFGF were added. The protein expression level was detected by Western blot, and apoptosis was determined by flow cytometry. The effect of BFGF on CAVD process in vivo was assessed by a rat CAVD model, which was identified by echocardiography and Alizarin red staining. The expression level of BFGF in the aortic valve and serum were significantly upregulated in CAVD patients compared to control group. In addition, exogenous BFGF injection attenuates CAVD process in vivo. The protein markers of osteogenic differentiation, endoplasmic reticulum stress (ERS), and apoptosis were significantly upregulated by culture with OIM. On the contrary, the aforementioned proteins were suppressed after adding 100 ng/mL of BFGF. Inhibition of PI3K/Akt and ERK1/2 pathways by specific inhibitors abolished the protective effect of BFGF. In conclusion, BFGF could alleviate the VIC calcification by inhibiting ERS-mediated apoptosis, which is partly regulated by activation of the PI3K/Akt and ERK1/2 signaling pathways. BFGF may provide a potential avenue for CAVD therapy.

Matrix Metalloproteinase-Responsive Delivery of PEGylated Fibroblast Growth Factor 2

Attachment of polyethylene glycol (PEG) chains is a common, well-studied, and Food and Drug Administration-approved method to address the pharmacokinetic challenges of therapeutic proteins. Occasionally, PEGylation impairs the activity of pharmacodynamics (PD). To overcome this problem, disease-relevant cleavable linkers between the polymer and the therapeutic protein can unleash full PD by de-PEGylating the protein at its target site. In this study, we engineered a matrix metalloproteinase (MMP)-responsive fibroblast growth factor 2 (FGF-2) mutant that was site-specifically extended with a PEG polymer chain. Using bioinspired strategies, the bioconjugate was designed to release the native protein at the desired structure/environment with preservation of the proliferative capacity in vitro on NIH3T3 cells. In vivo, hepatic exposure was diminished but not its renal distribution over time compared to unconjugated FGF-2. By releasing the growth factor from the PEG polymer in response to MMP cleavage, restored FGF-2 may enter hard-to-reach tissues and activate cell surface receptors or nuclear targets.

Comparison of Four Protocols for In Vitro Differentiation of Human Embryonic Stem Cells into Trophoblast Lineages by BMP4 and Dual Inhibition of Activin/Nodal and FGF2 Signaling

Human embryonic stem cells (hESCs) cultured in media containing bone morphogenic protein 4 (BMP4; B) differentiate into trophoblast-like cells. Supplementing media with inhibitors of activin/nodal signaling (A83-01) and of fibroblast growth factor 2 (PD173074) suppresses mesoderm and endoderm formation and improves specification of trophoblast-like lineages, but with variable effectiveness. We compared differentiation in four BMP4-containing media: mTeSR1-BMP4 only, mTeSR1-BAP, basal medium with BAP (basal-BAP), and a newly defined medium, E7-BAP. These media variably drive early differentiation towards trophoblast-like lineages with upregulation of early trophoblast markers CDX2 and KRT7 and downregulation of pluripotency markers (OCT4 and NANOG). As expected, based on differences between media in FGF2 and its inhibitors, downregulation of mesendoderm marker EOMES was variable between media. By day 7, only hESCs grown in E7-BAP or basal-BAP expressed HLA-G protein, indicating the presence of cells with extravillous trophoblast characteristics. Expression of HLA-G and other differentiation markers (hCG, KRT7, and GCM1) was highest in basal-BAP, suggesting a faster differentiation in this medium, but those cultures were more inhomogeneous and still expressed some endodermal and pluripotency markers. In E7-BAP, HLA-G expression increased later and was lower. There was also a low but maintained expression of some C19MC miRNAs, with more CpG hypomethylation of the ELF5 promoter, suggesting that E7-BAP cultures differentiate slower along the trophoblast lineage. We conclude that while all protocols drive differentiation into trophoblast lineages with varying efficiency, they have advantages and disadvantages that must be considered when selecting a protocol for specific experiments.

Effects of Growth Factors on the Differentiation of Dental Stem Cells: A Systematic Review and Meta-analysis (Part I)

INTRODUCTION

To evaluate the biological interaction between dental stem cells (DSCs) and different growth factors in the field of regenerative endodontics.

METHODS

A systematic search was conducted in the electronic databases up to October 2021. This study followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Ex vivo studies evaluating the biological interactions of DSCs and growth factors were included. The meta-analysis was performed according to the type of growth factor. The outcomes were cell viability/ proliferation and mineralization. Standardized mean differences (SMDs) were estimated using the random-effect maximum-likelihood method (P < .05). Additional analysis was performed to find any potential source of heterogeneity.

RESULTS

Twenty articles were included in the systematic review; meta-analysis was performed for fibroblast growth factor-2 (FGF-2) and Transforming growth factor-ß1 (TGF-β1) (n = 5). Results showed that use of FGF-2 significantly increased cell proliferation on day 1-(SMD = 3.56, P = 0.00), 3-(SMD = 9.04, P = 0.00), 5-(SMD = 8.37, P = 0.01), and 7 (SMD=8.51, P=0.00) than the control group. TGF-ß1 increased alkaline phosphatase (ALP) activity more than control only on day 3 (SMD = 3.68, P = 0.02). TGF-β1 had no significant effect on cell proliferation on days 1 and 3 (P > 0.05) and on ALP activity on days 5 and 7 (P > 0.05). Meta-regression analysis showed that different covariates (i.e., cell type, passage number, and growth factors' concentration) could significantly influence the effect sizes at different follow- ups (P < 0.05).

CONCLUSION

Specific growth factors might enhance the proliferation and mineralization of DSCs; however, the obtained evidence was weak. Due to the high heterogeneity among the included studies, other growth factors' inhibitory/stimulatory effects on DSCs could not be evaluated.

Quercetin relieves coronary atherosclerosis via regulating fibroblast growth factor 2

This study aims to investigate the role of quercetin in coronary atherosclerosis and explore its possible mechanisms. Hematoxylin-eosin (H&E), immunohistochemical (IHC), and aniline blue staining were used to analyze the pathological changes in the cross-section of the aorta. Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Swiss Target Prediction, and PubChem were utilized to predict and screen the bioactive ingredients of traditional Chinese medicine (Huanglian, Yuxingcao, and Jinyinhua) for coronary atherosclerosis. Inflammatory factors and vascular protection parameters were quantitatively detected using ELISA and western blot. The proliferation and migration of vascular smooth muscle cells (VSMC) were evaluated using the Cell Counting Kit-8 (CCK-8), 5-ethynyl-2-deoxyuridine (EdU), and wound healing assays. The targets of quercetin were predicted using DisGeNET, Matascape, SWISSMODEL, cellular thermal shift assay (CETSA), and fluorescence titrimetric methods. Based on our findings, quercetin was identified as the active component of Huanglian, Yuxingcao, and Jinyinhua that exerted a positive effect on coronary atherosclerosis. In vivo and in vitro data demonstrated that quercetin improved the pathological changes in model mice and inhibited the proliferation, migration, and inflammatory response of VSMC cells. Specifically, we found that fibroblast growth factor 2 (FGF2) is a direct target of quercetin, and overexpression of FGF2 attenuated the anti-atherosclerosis function of quercetin. Overall, our study confirms the functional role of the quercetin-FGF2 axis in the progression of coronary atherosclerosis, providing a potential target for its treatment.

Mechanical stress-induced FGF-2 promotes proliferation and consequently induces osteoblast differentiation in mesenchymal stem cells

Mechanical stimuli serve as crucial regulators of bone mass, promoting bone formation. However, the molecular mechanisms governing how mesenchymal stem cells (MSCs) respond to mechanical cues during their differentiation into osteogenic cells remain elusive. In this study, we found that cyclic stretching enhances MSC proliferation but does not increase the expression of osteoblast-related genes. We further revealed that this proliferative effect is mediated by fibroblast growth factor 2 (FGF-2), synthesized by MSCs in response to mechanical stress. Cell proliferation induced by cyclic stretching was inhibited upon the addition of either U0126, an inhibitor of mitogen-activated protein kinase kinase (MEK), or early growth response 1 (EGR1)-targeting small-hairpin RNA (shRNA), indicating the involvement of the extracellular signal-regulated kinase (ERK)/EGR1 signaling pathway. Osteoblast differentiation, evaluated through ALP activity, osteoblast-related gene expression, and mineralization, was stimulated by recombinant human FGF-2 (rhFGF-2) when applied during the proliferation phase, but not when applied during the differentiation stage alone. Our results suggest that FGF-2 indirectly promotes osteoblast differentiation as a downstream effect of stimulating cell proliferation. For the first time, we demonstrate that cyclic stretching induces MSCs to produce FGF-2, which in turn encourages cell proliferation through an autocrine/paracrine mechanism, consequently leading to osteoblast differentiation.

HSP70 inhibitor amplifies the bFGF‑induced release of IL‑6 in osteoblasts

Heat shock protein 70 (HSP70) functions as an ATP‑dependent molecular chaperone under stress and is involved in protein homeostasis, folding and degradation. HSP70 inhibitors amplify TGF‑β‑stimulated VEGF synthesis in the mouse osteoblastic MC3T3‑E1 cell line. Basic fibroblast growth factor (bFGF) stimulates IL‑6 release via p38 MAPK in MC3T3‑E1 osteoblast‑like cells. In the present study, the effects of HSP70 on the bFGF‑stimulated release of IL‑6 was evaluated using MC3T3‑E1 osteoblast‑like cells. IL‑6 release and mRNA expression levels were analyzed using ELISA and reverse transcription‑quantitative PCR, respectively. Phosphorylation of p38 MAPK and HSP70 was assessed using western blotting. HSP70 inhibitor VER‑155008 significantly increased the bFGF‑stimulated release of IL‑6 in both MC3T3‑E1 osteoblastic cells and normal human osteoblasts. Furthermore, VER‑155008 significantly enhanced the mRNA expression levels of IL‑6 stimulated by bFGF. Western blotting demonstrated a significant increase in the bFGF‑stimulated phosphorylation of p38 MAPK in VER‑155008‑treated MC3T3‑E1 cells. A significant increase in the bFGF‑stimulated phosphorylation of p38 MAPK was also demonstrated in MC3T3‑E1 cells treated with YM‑08, another HSP70 inhibitor. VER‑155008 or YM‑08 did not significantly affect the expression of HSP70 with or without bFGF stimulation. Finally, the specific p38 MAPK inhibitor SB203580 markedly suppressed the enhancing effects of VER‑155008 on bFGF‑stimulated release of IL‑6. Taken together, these results indicated that HSP70 inhibitor amplified bFGF‑stimulated release of IL‑6 through p38 MAPK activation in the osteoblastic MC3T3‑E1 cell line.

Elucidating the Morphogenic and Signaling Roles of Defined Growth Factors Controlling Human Endothelial Cell Lumen Formation Versus Sprouting Behavior

Five growth factors [ie, insulin, fibroblast growth factor-2 (FGF-2), stem cell factor, IL-3, and stromal-derived factor 1α] in combination are necessary for human endothelial cells (ECs) to undergo tube morphogenesis, a process requiring both lumen formation and sprouting behavior. This study investigated why these factors are required by subdividing the factors into 4 separate groups: insulin-only, insulin and FGF-2, no FGF-2 (all factors but without FGF-2), and all factors. The study found that the insulin-only condition failed to support EC morphogenesis or survival, the insulin and FGF-2 condition supported primarily EC lumen formation, and the no FGF-2 condition supported EC sprouting behavior. By comparison, the all-factors condition more strongly stimulated both EC lumen formation and sprouting behavior, and signaling analysis revealed prolonged stimulation of multiple promorphogenic signals coupled with inhibition of proregressive signals. Pharmacologic inhibition of Jak kinases more selectively blocked EC sprouting behavior, whereas inhibition of Raf, phosphatidylinositol 3-kinase, and Akt kinases showed selective blockade of lumen formation. Inhibition of Src family kinases and Notch led to increased sprouting coupled to decreased lumen formation, whereas inhibition of Pak, Mek, and mammalian target of rapamycin kinases blocked both sprouting and lumen formation. These findings reveal novel downstream biological and signaling activities of defined factors that are required for the assembly of human EC-lined capillary tube networks.

Synergistic effect of FGF-2 and TGF-β1 on the mineralization of human umbilical cord perivascular cells

OBJECTIVE

Human umbilical cord perivascular cells (HUCPVCs) are derived from the human umbilical cord perivascular tissue and are expected to replace mesenchymal stromal cells in the future. We investigated the synergistic effects of fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 1 (TGF-β1) on HUCPVC mineralization.

DESIGN

We prepared HUCPVCs with (FGF(+)HUCPVCs) or without FGF-2 (FGF(-)HUCPVCs) in the presence of activated vitamin D3, a bone morphogenic protein inhibitor, and TGF-β1. We examined the cell proliferative capacity, expression of various hard tissue-forming cell gene markers, and mineralization induction ability and identified the crystalline phases of the mineralized nodules.

RESULTS

FGF(+)HUCPVCs exhibited higher intracellular alkaline phosphatase (ALP) gene expression and ALP activity, and their cell proliferation rate was higher than that of FGF(-)HUCPVCs. The expression levels of osteoblast marker genes increased in FGF(+)HUCPVCs, whereas those of elastic fiber and muscle cell markers increased in FGF(-)HUCPVCs. The expression of genes related to matrix vesicle-mediated mineralization was increased in FGF(+)HUCPVCs. While FGF(-)HUCPVCs displayed myofibroblast-like properties and could not induce mineralization, FGF(+)HUCPVCs demonstrated the ability to produce mineralized nodules. The resulting mineralized nodules consisted of hydroxyapatite as the major phase and minor amounts of octacalcium phosphate. The mineralized nodules exhibited the morphological characteristics of bone hydroxyapatite, composed of fibrous hydroxyapatite nanorods and polycrystalline sheets.

CONCLUSION

We found that FGF-2 synergizes with TGF-β1 and is a key factor in the differentiation of HUCPVCs into osteoblast-like cells. Thus, HUCPVCs can potentially serve as a new stem cell source for future bone regeneration and dental treatments.

Basic fibroblast growth factor promotes meniscus regeneration through the cultivation of synovial mesenchymal stem cells via the CXCL6-CXCR2 pathway

OBJECTIVE

To investigate the efficacy of basic fibroblast growth factor (bFGF) in promoting meniscus regeneration by cultivating synovial mesenchymal stem cells (SMSCs) and to validate the underlying mechanisms.

METHODS

Human SMSCs were collected from patients with osteoarthritis. Eight-week-old nude rats underwent hemi-meniscectomy, and SMSCs in pellet form, either with or without bFGF (1.0 × 106 cells per pellet), were implanted at the site of meniscus defects. Rats were divided into the control (no transplantation), FGF (-) (pellet without bFGF), and FGF (+) (pellet with bFGF) groups. Different examinations, including assessment of the regenerated meniscus area, histological scoring of the regenerated meniscus and cartilage, meniscus indentation test, and immunohistochemistry analysis, were performed at 4 and 8 weeks after surgery.

RESULTS

Transplanted SMSCs adhered to the regenerative meniscus. Compared with the control group, the FGF (+) group had larger regenerated meniscus areas, superior histological scores of the meniscus and cartilage, and better meniscus mechanical properties. RNA sequencing of SMSCs revealed that the gene expression of chemokines that bind to CXCR2 was upregulated by bFGF. Furthermore, conditioned medium derived from SMSCs cultivated with bFGF exhibited enhanced cell migration, proliferation, and chondrogenic differentiation, which were specifically inhibited by CXCR2 or CXCL6 inhibitors.

CONCLUSION

SMSCs cultured with bFGF promoted the expression of CXCL6. This mechanism may enhance cell migration, proliferation, and chondrogenic differentiation, thereby resulting in superior meniscus regeneration and cartilage preservation.

Thermostable Basic Fibroblast Growth Factor Enhances the Production and Activity of Human Wharton's Jelly Mesenchymal Stem Cell-Derived Extracellular Vesicles

Wharton's jelly-derived mesenchymal stem cell (WJ-MSC)-derived exosomes contain a diverse cargo and exhibit remarkable biological activity, rendering them suitable for regenerative and immune-modulating functions. However, the quantity of secretion is insufficient. A large body of prior work has investigated the use of various growth factors to enhance MSC-derived exosome production. In this study, we evaluated the utilization of thermostable basic fibroblast growth factor (TS-bFGF) with MSC culture and exosome production. MSCs cultured with TS-bFGF displayed superior proliferation, as evidenced by cell cycle analysis, compared with wild-type bFGF (WT-bFGF). Stemness was assessed through mRNA expression level and colony-forming unit (CFU) assays. Furthermore, nanoparticle tracking analysis (NTA) measurements revealed that MSCs cultured with TS-bFGF produced a greater quantity of exosomes, particularly under three-dimensional culture conditions. These produced exosomes demonstrated substantial anti-inflammatory and wound-healing effects, as confirmed by nitric oxide (NO) assays and scratch assays. Taken together, we demonstrate that utilization of TS-bFGF for WJ-MSC-derived exosome production not only increases exosome yield but also enhances the potential for various applications in inflammation regulation and wound healing.

The antiproliferative effect of FGF2 in K-Ras-driven tumor cells involves modulation of rRNA and the nucleolus

The nucleolus is sensitive to stress and can orchestrate a chain of cellular events in response to stress signals. Despite being a growth factor, FGF2 has antiproliferative and tumor-suppressive functions in some cellular contexts. In this work, we investigated how the antiproliferative effect of FGF2 modulates chromatin-, nucleolus- and rDNA-associated proteins. The chromatin and nucleolar proteome indicated that FGF2 stimulation modulates proteins related to transcription, rRNA expression and chromatin-remodeling proteins. The global transcriptional rate and nucleolus area increased along with nucleolar disorganization upon 24 h of FGF2 stimulation. FGF2 stimulation induced immature rRNA accumulation by increasing rRNA transcription. The rDNA-associated protein analysis reinforced that FGF2 stimulus interferes with transcription and rRNA processing. RNA Pol I inhibition partially reversed the growth arrest induced by FGF2, indicating that changes in rRNA expression might be crucial for triggering the antiproliferative effect. Taken together, we demonstrate that the antiproliferative FGF2 stimulus triggers significant transcriptional changes and modulates the main cell transcription site, the nucleolus.

Sustained growth factor delivery from bioactive PNIPAM-grafted-chitosan/heparin multilayers as a tool to promote growth and migration of cells

Delivery of growth factors (GFs) is challenging for regulation of cell proliferation and differentiation due to their rapid inactivation under physiological conditions. Here, a bioactive polyelectrolyte multilayer (PEM) is engineered by the combination of thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and glycosaminoglycans to be used as reservoir for GF storage. PNIPAM-grafted-chitosan (PChi) with two degrees of substitution (DS) are synthesized, namely LMW* (DS 0.14) and HMW (DS 0.03), by grafting low (2 kDa) and high (10 kDa) molecular weight of PNIPAM on the backbone of chitosan (Chi) to be employed as polycations to form PEM with the polyanion heparin (Hep) at pH 4. Subsequently, PEMs are chemically crosslinked to improve their stability at physiological pH 7.4. Resulting surface and mechanical properties indicate that PEM containing HMW is responsive to temperature at 20 °C and 37 °C, while LMW is not. More importantly, Hep as terminal layer combined with HMW allows not only a better retention of the adhesive protein vitronectin but also a sustained release of FGF-2 at 37 °C. With the synergistic effect of vitronectin and matrix-bound FGF-2, significant promotion on adhesion, proliferation, and migration of 3T3 mouse embryonic fibroblasts is achieved on HMW-containing PEM compared to Chi-containing PEM and exogenously added FGF-2. Thus, PEM containing PNIPAM in combination with bioactive glycosaminoglycans like Hep represents a versatile approach to fabricate a GF delivery system for efficient cell culture, which can be potentially served as cell culture substrate for production of (stem) cells and bioactive wound dressing for tissue regeneration.

A single administration of FGF2 after renal ischemia-reperfusion injury alleviates post-injury interstitial fibrosis

BACKGROUND

Despite lack of clinical therapy in acute kidney injury (AKI) or its progression to chronic kidney disease (CKD), administration of growth factors shows great potential in the treatment of renal repair and further fibrosis. At an early phase of AKI, administration of exogenous fibroblast growth factor 2 (FGF2) protects against renal injury by inhibition of mitochondrial damage and inflammatory response. Here, we investigated whether this treatment attenuates the long-term renal interstitial fibrosis induced by ischemia-reperfusion (I/R) injury.

METHODS

Unilateral renal I/R with contralateral nephrectomy was utilized as an in vivo model for AKI and subsequent CKD. Rats were randomly divided into four groups: Sham-operation group, I/R group, I/R-FGF2 group and FGF2-3D group. These groups were monitored for up to 2 months. Serum creatinine, inflammatory response and renal histopathology changes were detected to evaluate the role of FGF2 in AKI and followed renal interstitial fibrosis. Moreover, the expression of vimentin, α-SMA, CD31 and CD34 were examined.

RESULTS

Two months after I/R injury, the severity of renal interstitial fibrosis was significantly attenuated in both of I/R-FGF2 group and FGF2-3D group, compared with the I/R group. The protective effects of FGF2 administration were associated with the reduction of high-mobility group box 1 (HMGB1)-mediated inflammatory response, the inhibition of transforming growth factor beta (TGF-β1)/Smads signaling-induced epithelial-mesenchymal transition and the maintenance of peritubular capillary structure.

CONCLUSIONS

A single dose of exogenous FGF2 administration 1 h or 3 days after reperfusion inhibited renal fibrogenesis and thus blocked the transition of AKI to CKD. Our findings provided novel insight into the role of FGF signaling in AKI-to-CKD progression and underscored the potential of FGF-based therapy for this devastating disease.

Effects of follicle-stimulating hormone, insulin-like growth factor 1, fibroblast growth factor 2, and fibroblast growth factor 9 on sirtuins expression and histone deacetylase activity in bovine granulosa cells

Granulosa cells (GC) are critical regulators of fertility. During the process of ovarian folliculogenesis, these cells undergo profound changes while producing steroid hormones that are important to control follicular growth, oocyte maturation, and ovulation. Sirtuins are enzymes that regulate several biological processes and have been associated with control of GC function. However, how sirtuins are regulated in GC during ovarian folliculogenesis remains to be unveiled. The present study was designed to investigate effects of hormones that control GC proliferation, differentiation, and steroidogenesis on expression of the seven members of the mammalian sirtuins family (SIRT1-7) and on histone deacetylase activity of nuclear sirtuins (SIRT1, 6, and 7) in GC. Bovine granulosa cells were isolated from small antral follicles (1-5 mm) and were treated with or without follicle-stimulating hormone (FSH), insulin-like growth factor 1 (IGF-1), and fibroblast growth factors 2 (FGF2) and 9 (FGF9). Following treatments, cell proliferation was determined via a cell analyzer, estradiol synthesis and histone deacetylase activity were determined via ELISA, and sirtuins mRNA expression was determined via qPCR. Treatments with FSH and IGF-1 stimulated cell proliferation while addition of FGF2 or FGF9 suppressed estradiol production stimulated by FSH plus IGF-1. In terms of treatments that regulated sirtuins expression in GC, fibroblast growth factors were the most impactful: FGF2 alone increased SIRT1 mRNA expression in comparison to several treatments and increased mRNA abundance of SIRT2 and SIRT7 when added to the combination of FSH and IGF-1; the addition of FGF9 to the combination of FSH and IGF-1 increased mRNA expression of SIRT2, SIRT3, SIRT4, SIRT6, and SIRT7 and increased mRNA expression of SIRT5 in comparison to the negative control group that received no treatment. Also, FGF2 alone increased histone deacetylase activity of sirtuins in comparison to all treatments that contained FSH and/or IGF-1. Furthermore, several correlations were observed between treatments and sirtuins expression and activity, between estradiol or GC numbers and sirtuins expression, and between expression of sirtuins. As FGF2 and FGF9 are considered anti-differentiation factors of GC that stimulate GC proliferation while suppressing estradiol production in combination with FSH and IGF-1, data of this study suggest that sirtuins are associated with control of differentiation of bovine GC.

Fabrication of water-dispersible and cell-stimulating calcium phosphate nanoparticles immobilizing basic fibroblast growth factor

Basic fibroblast growth factor (bFGF) is a therapeutic protein that can enhance angiogenesis, wound healing, and tissue regeneration; however, it is extremely unstable even under a normal physiological environment. Biocompatible calcium phosphate (CaP) nanoparticles (NPs) co-immobilizing bFGF, heparin, and ferucarbotran would be useful as a multifunctional delivery carrier of bFGF. In this study, such NPs were successfully fabricated by a coprecipitation process, using a labile supersaturated CaP solution containing bFGF, heparin, and ferucarbotran. The NPs showed relatively high negative zeta potential (-12 mV) because of the negatively charged heparin, which enabled their stable dispersion in water. The hydrodynamic diameter of the NPs was around 200 nm. Immunoreactive bFGF was released from the NPs in an acellular medium dose-dependently. The NPs promoted proliferation of baby hamster kidney fibroblasts (BHK-21 cells) and mouse osteoblastic MC3T3-E1 cells at a certain dose range, although they inhibited proliferation of rat pheochromocytoma (PC-12) cells. These results demonstrated that the effect of the NPs on cell proliferation was dependent on the cell type and dose, the details of which should be investigated in a future study.

Topical Cream Derived From Hylocereus polyrhizus (Red Dragon Fruit) Extract Accelerates Wound Healing Through Increased Hydroxyproline and Fibroblast Growth Factor 2 Levels: A Pilot Study

The red dragon fruit (Hylocereus polyrhizus) extract (RDFE) is frequently used for a variety of therapeutic purposes (e.g., boosting the immune system, promoting a healthy gastrointestinal system, improving wound healing). We investigated the effects of a topical cream containing 7.5% RDFE on hydroxyproline and fibroblast growth factor 2 (FGF-2) levels and wound healing. On Day 0, we divided a total of 36 albino male Wistar rats into two equal groups. Using an 8-mm punch biopsy, we created a circular excision to fascial depth on the back of each rat. On Day 1, we treated the control group (n = 18) with 20 mg of base cream and the RDFE group (n = 18) with 20 mg of 7.5% RDFE cream. We measured hydroxyproline and FGF-2 levels in the wound tissue using an ELISA method on Days 3, 7, and 14. We found that on Day 3, hydroxyproline levels were significantly lower in the treatment group than in the control group (p = .031). We also found a significant correlation between FGF-2 levels in the treatment group and wound diameter (p = .02). On the basis of the results of this study, we concluded that using a topical cream containing 7.5% RDFE has the potential to accelerate wound healing by increasing levels of hydroxyproline and FGF-2 in the wound.

Growth Factor Immobilization to Synthetic Hydrogels: Bioactive bFGF-Functionalized Polyisocyanide Hydrogels

With its involvement in cell proliferation, migration and differentiation basic fibroblast growth factor (bFGF) has great potential for tissue engineering purposes. So far, however, clinical translation of soluble bFGF-based therapies is unsuccessful, because the required effective doses are often supraphysiological, which may cause adverse effects. An effective solution is growth factor immobilization, whereby bFGF retains its bioactivity at increased efficacy. Studied carriers include films, solid scaffolds, and particles, as well as natural and synthetic hydrogels. However, these synthetic hydrogels poorly resemble the characteristics of the native extracellular matrix (ECM). In this work, bFGF is covalently conjugated to the synthetic, but highly biocompatible, polyisocyanide-based hydrogel (PIC-bFGF), which closely mimics the architecture and mechanical properties of the ECM. The growth factor conjugation protocol is straightforward and readily extrapolated to other growth factors or proteins. The PIC-bFGF hydrogel shows a prolonged bioactivity up to 4 weeks although no clear effects on the ECM metabolism are observed. Beyond the future potential of the PIC-bFGF hydrogel toward various tissue engineering applications, this work underlines that simple biological conjugation procedures are a powerful strategy to induce additional bioactivity in 3D synthetic cell culture matrices.

Lychnophora ericoides Mart. (Brazilian arnica) ethanol extract accelerates the skin wound healing process: Evidence for its mechanism of action

BACKGROUND

Lychnophora ericoides Mart, also known as the Brazilian arnica or fake arnica, belongs to the Asteraceae family. Leaves and roots are used in alcoholic and hydroalcoholic preparations for the treatment of wounds, inflammation, and pain.

PURPOSE

The present study aimed to investigate the effects of L. ericoides ethanolic extract (EELE) on cutaneous wound healing and the mechanisms of action involved.

METHODS

A total of 72 C57BL/6 mice were randomly divided into four groups of six animals each. An excisional wound was made in the dorsal region of each mouse. The test groups were topically treated with the vehicle, a positive control commercial reference drug, EELE ointment (5%), and EELE ointment (10%). The treatments were applied over 14 days. The wound area was measured every two days to verify the wound closure kinetics. On days 3, 7, and 14 the wound tissue samples were processed for Hematoxylin and Eosin, Masson-Trichrome, and Toluidine blue staining. The expression of renin-angiotensin system (RAS) components, the vascular growth factor-A (VEGF-A), the basic fibroblast growth factor (FGF-2), and type I collagen genes were evaluated. Phytochemical analyses were performed using HPLC-DAD and HPLC-MS/MS.

RESULTS

The EELE (10%) significantly reduced the wound area compared to the treatments used for the other groups. Histological analysis demonstrated that wounds treated with L. ericoides for 14 days developed improved anatomical skin features, healed with hair follicles and sebaceous glands, increased collagen production and angiogenesis, and decreased the number of mast cells at the injury site. Real-time PCR data demonstrated that groups treated with EELE (10%) showed increased Type I collagen, VEGF-A, FGF-2, and AT1R and decreased ACE II and receptor MAS. The healing action of L. ericoides may be related to the presence of phenolic compounds, such as phenolic acids, chlorogenic acid derivatives, and C-glycoside flavonoids.

CONCLUSION

Topical treatment with EELE increases important factors for wound healing: FGF, VEGF, collagen formation, and the expression of the proliferative axis of the renin-angiotensin system. For the first time, the present study shows the healing action of L. ericoides at the molecular level in an animal model. This process can be used as an alternative therapy for wound healing and the development of herbal therapy.

Secured delivery of basic fibroblast growth factor using human serum albumin-based protein nanoparticles for enhanced wound healing and regeneration

BACKGROUND

Basic fibroblast growth factor (bFGF) is one of the critical components accelerating angiogenesis and tissue regeneration by promoting the migration of dermal fibroblasts and endothelial cells associated with matrix formation and remodeling in wound healing process. However, clinical applications of bFGF are substantially limited by its unstable nature due to rapid decomposition under physiological microenvironment.

RESULTS

In this study, we present the bFGF-loaded human serum albumin nanoparticles (HSA-bFGF NPs) as a means of enhanced stability and sustained release platform during tissue regeneration. Spherical shape of the HSA-bFGF NPs with uniform size distribution (polydispersity index < 0.2) is obtained via a simple desolvation and crosslinking process. The HSA-bFGF NPs securely load and release the intact soluble bFGF proteins, thereby significantly enhancing the proliferation and migration activity of human dermal fibroblasts. Myofibroblast-related genes and proteins were also significantly down-regulated, indicating decrease in risk of scar formation. Furthermore, wound healing is accelerated while achieving a highly organized extracellular matrix and enhanced angiogenesis in vivo.

CONCLUSION

Consequently, the HSA-bFGF NPs are suggested not only as a delivery vehicle but also as a protein stabilizer for effective wound healing and tissue regeneration.

Feeding rumen-protected lysine prepartum alters placental metabolism at a transcriptional level

Rumen-protected Lys (RPL) fed to Holstein cows prepartum resulted in a greater intake and improved health of their calves during the first 6 wk of life. However, whether increased supply of Lys in late gestation can influence placental tissue and, if so, which pathways are affected remain to be investigated. Therefore, we hypothesize that feeding RPL during late gestation could modulate placental metabolism, allowing for improved passage of nutrients to the fetus and thus influencing the offspring development. Therefore, we aimed to determine the effects of feeding RPL (AjiPro-L Generation 3, Ajinomoto Health and Nutrition North America) prepartum (0.54% DM of TMR) on mRNA gene expression profiles of placental samples of Holstein cows. Seventy multiparous Holstein cows were randomly assigned to 1 of 2 dietary treatments, consisting of TMR top-dressed with RPL (PRE-L) or without (control, CON), fed from 27 ± 5 d prepartum until calving. After natural delivery (6.87 ± 3.32 h), placentas were rinsed with physiological saline (0.9% sodium chloride solution) to clean any dirtiness from the environment and weighed. Then, 3 placentomes were collected, one from each placental region (cranial, central, and caudal), combined and flash-frozen in liquid nitrogen to evaluate the expression of transcripts and proteins related to protein metabolism and inflammation. Placental weights did not differ from cows in PRE-L (15.5 ± 4.03 kg) and cows in CON (14.5 ± 4.03 kg). Feeding RPL prepartum downregulated the expression of NOS3 (nitric oxide synthase 3), involved in vasodilation processes, and SOD1, which encodes the enzyme superoxide dismutase, involved in oxidative stress processes. Additionally, feeding RPL prepartum upregulated the expression of transcripts involved in energy metabolism (SLC2A3, glucose transporter 3; and PCK1, phosphoenolpyruvate carboxykinase 1), placental metabolism and cell proliferation (FGF2, fibroblast growth factor 2; FGF2R, fibroblast growth factor 2 receptor; and PGF, placental growth factor), Met metabolism (MAT2A, methionine adenosyltransferase 2-α), and tended to upregulate IGF2R (insulin-like growth factor 2 receptor). Placental FGF2 and LRP1 (low-density lipoprotein receptor-related protein 1) protein abundance were greater for cows that received RPL prepartum than cows in CON. In conclusion, feeding RPL to prepartum dairy cows altered uteroplacental expression of genes and proteins involved in cell proliferation, and in metabolism and transport of glucose. Such changes are illustrated by increased expression of SLC2A3 and PCK1 and increased protein abundance of FGF2 and LRP1 in uteroplacental tissue of cows consuming RPL.

Safety of terminally gamma-ray-sterilized screws coated with fibroblast growth factor 2-calcium phosphate composite layers in non-human primates

Screws coated with fibroblast growth factor 2 (FGF-2)-calcium phosphate (CP) composite layers exhibit enhanced soft tissue and bone formation and angiogenesis because of the biological activity of FGF-2. Furthermore, the mitogenic activity of the FGF-2 within the composite layers remains unchanged after gamma-ray sterilization, which may improve the storage stability prior to clinical use. However, the in vivo safeties of these screws as spinal implants remain unknown. Here, a randomized controlled trial, involving non-human primates, investigated the safety of using FGF-2-CP composite layer-coated screws after either gamma-ray sterilization or aseptic processing. Titanium alloy screws coated with FGF-2-CP composite layers and subjected to either gamma-ray sterilization at 25 kGy (GS group) or aseptic storage (AS group) were implanted into the vertebral bodies of two cynomolgus monkeys exceeding 12 weeks (day 99). Physiological, histological, and radiographic investigations were performed to evaluate the safeties of the screws. There were no serious adverse events, such as surgical site infection, significant loss of body weight, or abnormal blood test results. No radiolucent areas were observed around the screws from the GS or AS group throughout the study. In the intraosseous region, no significant differences were observed in bone and fibrous tissue apposition rates and rate of bone formation between the two groups (p = 0.49, 0.77, and 0.11, respectively). Neither tumor lesions nor accumulation of lymphocytes and neutrophils were observed in either group. Our data suggest that FGF-2-CP composite layer-coated screws subjected to terminal gamma-ray sterilization are as safe as those fabricated in aseptic processing.

Treatment of aged wound healing models with FGF2 and ABT-737 reduces the senescent cell population and increases wound closure rate

Delayed tissue repair in the aged presents a major socio-economic and clinical problem. Age-associated delay in wound healing can be attributed to multiple factors, including an increased presence of senescent cells persisting in the wound. Although the transient presence of senescent cells is physiologic during the resolution phase of normal healing, increased senescent cell accumulation with age can negatively impact tissue repair. The objective of the study was to test interventional strategies that could mitigate the negative effect of senescent cell accumulation and possibly improve the age-associated delay in wound healing. We utilised a 3D in vitro senescent fibroblast populated collagen matrix (FPCM) to study cellular events associated with senescence and delayed healing. Senescent fibroblasts showed an increase in anti-apoptotic B-cell lymphoma 2 (BCL-2) family proteins. We hypothesized that reducing the senescent cell population and promoting non-senescent cell functionality would mitigate the negative effect of senescence and improve healing kinetics. BCL-2 inhibition and mitogen stimulation (FGF2) improved healing in the in vitro senescent models. These results were confirmed with an ex vivo human skin biopsy model. These data suggested that modulation of the senescent cell population with soluble factors improved the healing outcome in our in vitro and ex vivo healing models.

Axonal Regrowth of Olfactory Sensory Neurons In Vitro

One of the most prevalent causes of olfactory loss includes traumatic brain injury with subsequent shearing of olfactory axons at the level of the cribriform plate (anterior skull base). Scar tissue at this level may prevent axonal regrowth toward the olfactory bulb. Currently, there is no cure for this debilitating and often permanent condition. One promising therapeutic concept is to implant a synthetic scaffold with growth factors through the cribriform plate/scar tissue to induce neuroregeneration. The first step toward this goal is to investigate the optimum conditions (growth factors, extracellular matrix proteins) to boost this regeneration. However, the lack of a specifically tailored in vitro model and an automated procedure for quantifying axonal length limits our ability to address this issue. The aim of this study is to create an automated quantification tool to measure axonal length and to determine the ideal growth factors and extracellular proteins to enhance axonal regrowth of olfactory sensory neurons in a mouse organotypic 2D model. We harvested olfactory epithelium (OE) of C57BL/6 mice and cultured them during 15 days on coverslips coated with various extracellular matrix proteins (Fibronectin, Collagen IV, Laminin, none) and different growth factors: fibroblast growth factor 2 (FGF2), brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF), retinoic acid (RA), transforming growth factor β (TGFβ), and none. We measured the attachment rate on coverslips, the presence of cellular and axonal outgrowth, and finally, the total axonal length with a newly developed automated high-throughput quantification tool. Whereas the coatings did not influence attachment and neuronal outgrowth rates, the total axonal length was enhanced on fibronectin and collagen IV (p = 0.001). The optimum growth factor supplementation media to culture OE compared to the control condition were as follows: FGF2 alone and FGF2 from day 0 to 7 followed by FGF2 in combination with NGF from day 7 to 15 (p < 0.0001). The automated quantification tool to measure axonal length outperformed the standard Neuron J application by reducing the average analysis time from 22 to 3 min per specimen. In conclusion, robust regeneration of murine olfactory neurons in vitro can be induced, controlled, and efficiently measured using an automated quantification tool. These results will help advance the therapeutic concept closer toward preclinical studies.

Elucidating Fibroblast Growth Factor-Induced Kinome Dynamics Using Targeted Mass Spectrometry and Dynamic Modeling

Fibroblast growth factors (FGFs) are paracrine or endocrine signaling proteins that, activated by their ligands, elicit a wide range of health and disease-related processes, such as cell proliferation and the epithelial-to-mesenchymal transition. The detailed molecular pathway dynamics that coordinate these responses have remained to be determined. To elucidate these, we stimulated MCF-7 breast cancer cells with either FGF2, FGF3, FGF4, FGF10, or FGF19. Following activation of the receptor, we quantified the kinase activity dynamics of 44 kinases using a targeted mass spectrometry assay. Our system-wide kinase activity data, supplemented with (phospho)proteomics data, reveal ligand-dependent distinct pathway dynamics, elucidate the involvement of not earlier reported kinases such as MARK, and revise some of the pathway effects on biological outcomes. In addition, logic-based dynamic modeling of the kinome dynamics further verifies the biological goodness-of-fit of the predicted models and reveals BRAF-driven activation upon FGF2 treatment and ARAF-driven activation upon FGF4 treatment.

Enhanced Bone Formation by Rapidly Formed Bony Wall over the Bone Defect Using Dual Growth Factors

BACKGROUND

In guided bone regeneration (GBR), there are various problems that occur in the bone defect after the wound healing period. This study aimed to investigate the enhancement of the osteogenic ability of the dual scaffold complex and identify the appropriate concentration of growth factors (GF) for new bone formation based on the novel GBR concept that is applying rapid bone forming GFs to the membrane outside of the bone defect.

METHODS

Four bone defects with a diameter of 8 mm were formed in the calvaria of New Zealand white rabbits each to perform GBR. Collagen membrane and biphasic calcium phosphate (BCP) were applied to the bone defects with the four different concetration of BMP-2 or FGF-2. After 2, 4, and 8 weeks of healing, histological, histomorphometric, and immunohistochemical analyses were conducted.

RESULTS

In the histological analysis, continuous forms of new bones were observed in the upper part of bone defect in the experimental groups, whereas no continuous forms were observed in the control group. In the histomorphometry, The group to which BMP-2 0.5 mg/ml and FGF-2 1.0 mg/ml was applied showed statistically significantly higher new bone formation. Also, the new bone formation according to the healing period was statistically significantly higher at 8 weeks than at 2, 4 weeks.

CONCLUSION

The novel GBR method in which BMP-2, newly proposed in this study, is applied to the membrane is effective for bone regeneration. In addition, the dual scaffold complex is quantitatively and qualitatively advantageous for bone regeneration and bone maintenance over time.

The inhibition of mineralisation by fibroblast growth factor 2 is associated with the altered expression of genes regulating phosphate balance

The study aimed to determine whether inhibitory effects of fibroblast growth factor 2 (FGF2) on mineralisation in dental pulp (DP) cultures were associated with changes in the expression of genes regulating phosphate balance (Enpp1, Ank, Slc20a2, Alpl, Phospho1, and Xpr1). DP cultures growing under mineralisation-inducing conditions were exposed to FGF2 and inhibitors of the FGFR and MEK/ERK1/2 signaling pathways. Mineralisation, culture cellularity, and gene expression were examined at various time points. Statistical analysis was performed using analysis of variance followed by the Holm-Šídák test. Control cultures exhibited transient increases in Enpp1 and Ank, continuous increases in Alpl, Phospho1, and Xpr1, and continuous decreases in Slc20a2. FGF2 increased Enpp1, Ank, and Slc20a2 and decreased Alpl, Phospho1, and Xpr1, whereas the FGF2 withdrawal and inhibition of FGFR and MEK/ERK1/2 exerted opposite effects. These changes suggest that FGF2-mediated decreases in mineralisation could be functionally coupled to the altered regulation of phosphate formation and transport.

Sustained release of basic fibroblast growth factor in micro/nanofibrous scaffolds promotes annulus fibrosus regeneration

Tissue engineering has promising applications in the treatment of intervertebral disc degeneration (IDD). The annulus fibrosus (AF) is critical for maintaining the physiological function of the intervertebral disc (IVD), but the lack of vessels and nutrition in AF makes it difficult to repair. In this study, we used hyaluronan (HA) micro-sol electrospinning and collagen type I (Col-I) self-assembly techniques to fabricate layered biomimetic micro/nanofibrous scaffolds, which released basic fibroblast growth factor (bFGF) to promote AF repair and regeneration after discectomy and endoscopic transforaminal discectomy. The bFGF enveloped in the core of the poly-L-lactic-acid (PLLA) core-shell structure was released in a sustained manner and promoted the adhesion and proliferation of AF cells (AFCs). Col-I could self-assemble on the shell of the PLLA core-shell scaffold to mimic the extracellular matrix (ECM) microenvironment, providing structural and biochemical cues for the regeneration of AF tissue. The in vivo studies showed that the micro/nanofibrous scaffolds promoted the repair of AF defects by simulating the microstructure of native AF tissue and inducing endogenous regeneration mechanism. Taken together, the biomimetic micro/nanofibrous scaffolds have clinical potential for the treatment of AF defects caused by IDD. STATEMENT OF SIGNIFICANCE: The annulus fibrosus (AF) is essential for the intervertebral disc (IVD) physiological function, yet it lacks vascularity and nutrition, making repair difficult. Micro-sol electrospinning technology and collagen type I (Col-I) self-assembly technique were combined in this study to create a layered biomimetic micro/nanofibrous scaffold that releases basic fibroblast growth factor (bFGF) to promote AF repair and regeneration. Col-I could mimic the extracellular matrix (ECM) microenvironment, in vivo, offering structural and biochemical cues for AF tissue regeneration. This research indicates that micro/nanofibrous scaffolds have clinical potential for treating AF deficits induced by IDD.

Regulation of FGF2-induced proliferation by inhibitory GPCR in normal pituitary cells

Introduction

Intracellular communication is essential for the maintenance of the anterior pituitary gland plasticity. The aim of this study was to evaluate whether GPCR-Gαi modulates basic fibroblast growth factor (FGF2)-induced proliferative activity in normal pituitary cell populations.

Methods

Anterior pituitary primary cell cultures from Wistar female rats were treated with FGF2 (10ng/mL) or somatostatin analog (SSTa, 100nM) alone or co-incubated with or without the inhibitors of GPCR-Gαi, pertussis toxin (PTX, 500nM), MEK inhibitor (U0126, 100µM) or PI3K inhibitor (LY 294002, 10 μM).

Results

FGF2 increased and SSTa decreased the lactotroph and somatotroph BrdU uptak2e (p<0.05) whereas the FGF2-induced S-phase entry was prevented by SSTa co-incubation in both cell types, with these effects being reverted by PTX, U0126 or LY294002 pre-incubation. The inhibition of lactotroph and somatotroph mitosis was associated with a downregulation of c-Jun expression, a decrease of phosphorylated (p) ERK and pAKT. Furthermore, SSTa was observed to inhibit the S-phase entry induced by FGF2, resulting in a further increase in the number of cells in the G1 phase and a concomitant reduction in the number of cells in the S phases (p< 0.05), effects related to a decrease of cyclin D1 expression and an increase in the expression of the cell cycle inhibitors p27 and p21.

Discussion

In summary, the GPCR-Gαi activated by SSTa blocked the pro-proliferative effect of FGF2 in normal pituitary cells via a MEK-dependent mechanism, which acts as a mediator of both anti and pro-mitogenic signals, that may regulate the principal effectors of the G1 to S-phase transition.

Melatonin increases collagen content accumulation and Fibroblast Growth Factor-2 secretion in cultured human cardiac fibroblasts

BACKGROUND

The extracellular matrix serves as a scaffold for cardiomyocytes, allowing them to work in accord. In rats, collagen metabolism within a myocardial infarction scar is regulated by melatonin. The present study determines whether melatonin influences matrix metabolism within human cardiac fibroblast cultures and examines the underlying mechanism.

METHODS

The experiments were performed on cultures of cardiac fibroblasts. The Woessner method, 1,9-dimethylmethylene blue assay, enzyme-linked immunosorbent assay and quantitative PCR were used in the study.

RESULTS

Melatonin treatment lowered the total cell count within the culture, elevated necrotic and apoptotic cell count as well as augmented cardiac fibroblast proliferation, and increased total, intracellular, and extracellular collagen within the fibroblast culture; it also elevated type III procollagen α1 chain expression, without increasing procollagen type I mRNA production. The pineal hormone did not influence matrix metalloproteinase-2 (MMP-2) release or glycosaminoglycan accumulation by cardiac fibroblasts. Melatonin increased the release of Fibroblast Growth Factor-2 (FGF-2) by human cardiac fibroblasts, but cardiotrophin release was not influenced.

CONCLUSION

Within human cardiac fibroblast culture, collagen metabolism is regulated by melatonin. The profibrotic effect of melatonin depends on the elevation of procollagen type III gene expression, and this could be modified by FGF-2. Two parallel processes, viz., cell elimination and proliferation, induced by melatonin, lead to excessive replacement of cardiac fibroblasts.

Changes Induced by Inflammatory-Activated Immune Cell Microenvironment in the Paracrine Profile of MSC

We studied the influence of activated innate and adaptive immune cells on the production of growth factors by human adipose tissue multipotent mesenchymal stromal cells (MSC). MSC showed immunosuppressive properties in vitro: decreased activation and proliferation of stimulated immune cells. T-cell interaction with MSC resulted with increased secretion of EGF, PDGF-AB/BB, FGF-2, and VEGF growth factors. Co-culturing with natural killer cells also stimulated TGFα production. The intensity of the effect varied depending on the type of immune cells. Natural killer caused a more significant increase in PDGF-AB/BB and FGF-2 secretion, while VEGF secretion increased stronger after co-culturing with T cells. The obtained data indicate the possibility of increasing reparative potential of MSC under the influence of inflammatory microenvironment.

The BMP and FGF pathways reciprocally regulate odontoblast differentiation

PURPOSE

Previous studies demonstrated that the exposure of primary dental pulp (DP) cultures to fibroblast growth factor 2 (FGF2) between days 3-7 exerted significant and long-lasting stimulatory effects on odontoblast differentiation and Dspp expression. These effects involved the increased expression of components of bone morphogenetic protein (BMP) signaling and were reverted by a BMP inhibitor noggin. FGF2 also transiently stimulated osteoblast differentiation and the expression of Ibsp and Dmp1. The present study aimed to further explore interactions between BMP and FGF signaling during odontoblast and osteoblast differentiation in DP cultures.

MATERIALS AND METHODS

Cultures were established using DP tissue isolated from non-transgenic and fluorescent reporter (DSPP-Cerulean, BSP-GFP, and DMP1-mCherry) transgenic mice and exposed to BMP2, FGF2, SU5402 (an FGF receptor inhibitor), and noggin between days 3-7. Mineralization, gene expression, fluorescent protein expression, and odontoblast formation were examined using xylenol orange, quantitative PCR, fluorometric analysis, and immunocytochemistry, respectively.

RESULTS

BMP2 activated SMAD1/5/8 but not ERK1/2 signaling, whereas FGF2 exerted opposite effects. BMP2 did not affect mineralization, the expression of Ibsp and Dmp1, and the percentage of DSPP-Cerulean+ odontoblasts but significantly increased Dspp and DSPP-Cerulean. In cultures exposed to BMP2 and FGF2, respectively, both SU5402 and noggin led to long-lasting decreases in Dspp and DSPP-Cerulean and transient decreases in Dmp1 and DMP1-mCherry without affecting Ibsp and BSP-GFP.

CONCLUSION

BMP2 and FGF2 exerted reciprocal stimulatory effects on odontoblast differentiation, whereas their effects on osteoblast differentiation were mediated independently. These data will further elucidate the perspectives of using BMP2 and FGF2 for dentin regeneration/repair.

Effect of acupuncture on the opening time of implantation window and endometrial receptivity in controlled ovarian hyperstimulation rats during peri-implantation period

PURPOSE

To investigate the effect of acupuncture for improving the pregnancy rate of COH rats from the viewpoint of regulating the opening time of the implantation window and endometrial receptivity.

METHODS

Experimental rats were randomly divided into normal group (N), model group (M) and acupuncture group(A), and samples were collected on Day 4, 5 and 6 after mating. COH rats were treated with acupuncture at SP6, LR3, and ST36 once a day for 7 times. The pinopodes were observed under a scanning electron microscope. Serum estrogen and progesterone levels were measured via ELISA. The protein and mRNA levels of estrogen receptor (ER), progesterone receptor (PR), leukemia inhibitory factor (LIF), integrin β3, vascular endothelial growth factor (VEGF), and fibroblast growth factor 2 (FGF-2) in the endometrium were evaluated via West-blot, immunohistochemistry, and PCR.

RESULTS

Compared with group N, the pregnancy rate of group M was significantly decreased (P<0.05), and the abnormal serum hormone levels and implantation window advancement were observed. Compared with group M, the pregnancy rate of group A was significantly increased (P<0.05), the supraphysiological serum progesterone levels were restored to normalcy (P<0.05), and the advanced implantation window was restored to a certain extent. Further, the abnormal ER, PR, LIF, integrin β3, VEGF, and FGF-2 expression levels of the endometrium got recovered to varying degrees.

CONCLUSION

Acupuncture may restore the estrogen and progesterone balance in COH rats and the forward shift of the implantation window to a certain extent, improving the endometrial receptivity and finally improving the pregnancy rate of COH rats.

Osteogenic Potential of Sheep Mesenchymal Stem Cells Preconditioned with BMP-2 and FGF-2 and Seeded on an nHAP-Coated PCL/HAP/β-TCP Scaffold

Mesenchymal stem cells (MSCs) attract interest in regenerative medicine for their potential application in bone regeneration. However, direct transplantation of cells into damaged tissue is not efficient enough to regenerate large bone defects. This problem could be solved with a biocompatible scaffold. Consequently, bone tissue engineering constructs based on biomaterial scaffolds, MSCs, and osteogenic cytokines are promising tools for bone regeneration. The aim of this study was to evaluate the effect of FGF-2 and BMP-2 on the osteogenic potential of ovine bone marrow-derived MSCs seeded onto an nHAP-coated PCL/HAP/β-TCP scaffold in vitro and its in vivo biocompatibility in a sheep model. In vitro analysis revealed that cells preconditioned with FGF-2 and BMP-2 showed a better capacity to adhere and proliferate on the scaffold than untreated cells. BM-MSCs cultured in an osteogenic medium supplemented with FGF-2 and BMP-2 had the highest osteogenic differentiation potential, as assessed based on Alizarin Red S staining and ALP activity. qRT-PCR analysis showed increased expression of osteogenic marker genes in FGF-2- and BMP-2-treated BM-MSCs. Our pilot in vivo research showed that the implantation of an nHAP-coated PCL/HAP/β-TCP scaffold with BM-MSCs preconditioned with FGF-2 and BMP-2 did not have an adverse effect in the sheep mandibular region and induced bone regeneration. The biocompatibility of the implanted scaffold-BM-MSC construct with sheep tissues was confirmed by the expression of early (collagen type I) and late (osteocalcin) osteogenic proteins and a lack of an elevated level of proinflammatory cytokines. These findings suggest that FGF-2 and BMP-2 enhance the osteogenic differentiation potential of MSCs grown on a scaffold, and that such a tissue engineering construct may be used to regenerate large bone defects.

Hydrogel Dressing Containing Basic Fibroblast Growth Factor Accelerating Chronic Wound Healing in Aged Mouse Model

Due to the decreasing self-repairing ability, elder people are easier to form chronic wounds and suffer from slow and difficult wound healing. It is desirable to develop a novel wound dressing that can accelerate chronic wound healing in elderly subjects to decrease the pain of patients and save medical resources. In this work, Heparin and basic fibroblast growth factor(bFGF) were dissolved in the mixing solution of 4-arm acrylated polyethylene glycol and dithiothreitol to form hydrogel dressing in vitro at room temperature without any catalysts, which is convenient and easy to handle in clinic application. In vitro re-lease test shows the bFGF could be continuously released for at least 7 days, whereas the dressing surface integrity maintained for 3 days degradation in PBS solution. Three groups of treatments including bFGF-Gel, bFGF-Sol and control without any treatment were applied on the full-thickness wound on the 22 months old mice back. The wound closure rate and histological and immunohistochemical staining all illustrated that bFGF-Gel displayed a better wound healing effect than the other two groups. Thus, as-prepared hydrogel dressing seems supe-rior to current clinical treatment and more effective in elderly subjects, which shows promising potential to be applied in the clinic.

Inhibition of FGFR Signaling by Targeting FGF/FGFR Extracellular Interactions: Towards the Comprehension of the Molecular Mechanism through NMR Approaches

NMR-based approaches play a pivotal role in providing insight into molecular recognition mechanisms, affording the required atomic-level description and enabling the identification of promising inhibitors of protein–protein interactions. The aberrant activation of the fibroblast growth factor 2 (FGF2)/fibroblast growth factor receptor (FGFR) signaling pathway drives several pathologies, including cancer development, metastasis formation, resistance to therapy, angiogenesis-driven pathologies, vascular diseases, and viral infections. Most FGFR inhibitors targeting the intracellular ATP binding pocket of FGFR have adverse effects, such as limited specificity and relevant toxicity. A viable alternative is represented by targeting the FGF/FGFR extracellular interactions. We previously identified a few small-molecule inhibitors acting extracellularly, targeting FGFR or FGF. We have now built a small library of natural and synthetic molecules that potentially act as inhibitors of FGF2/FGFR interactions to improve our understanding of the molecular mechanisms of inhibitory activity. Here, we provide a comparative analysis of the interaction mode of small molecules with the FGF2/FGFR complex and the single protein domains. DOSY and residue-level NMR analysis afforded insights into the capability of the potential inhibitors to destabilize complex formation, highlighting different mechanisms of inhibition of FGF2-induced cell proliferation.

Acceptance of Murine Islet Allografts Without Immunosuppression in Inguinal Subcutaneous White Adipose Tissue Pretreated With bFGF

Prevention of immune rejection without immunosuppression is the ultimate goal of transplant immunobiology. One way to achieve this in cellular transplantation, such as with islet transplantation, is to create a favorable local environment at the transplant site. In the current study, we found that C57BL/6 mice with streptozotocin-induced diabetes remained normoglycemic for >1 year after transplantation of BALB/c islets without immunosuppression when the inguinal subcutaneous white adipose tissue (ISWAT) was the site of transplantation and when the site was pretreated with basic fibroblast growth factor. Mechanistically, mesenchymal stem cells (MSCs) expanded in the ISWAT after the treatment was found to produce transforming growth factor-β (TGF-β), and prevention of islet allograft rejection could be achieved by cotransplantation with syngeneic MSCs isolated from the ISWAT after the treatment, which was abolished by anti-TGF-β antibody treatment. Importantly, TGF-β-producing cells remained present at the site of cotransplantation up to the end of observation period at 240 days after transplantation. These findings indicate that prevention of islet allograft rejection without immunosuppression is feasible with the use of syngeneic TGF-β-producing MSCs expanded in the ISWAT after the treatment with bFGF, providing a novel strategy for prevention of islet allograft rejection without immunosuppression.