Effect Of Fibroblast Growth Factor Research Articles

Fibroblast growth factor 2 promotes osteo/odontogenic differentiation in stem cells from the apical papilla by inhibiting PI3K/AKT pathway

Fibroblast growth factor 2 (FGF2) is a crucial factor in odontoblast differentiation and dentin matrix deposition, which facilitates pulpodentin repair and regeneration. Nevertheless, the specific biological function of FGF2 in odontoblastic differentiation remains unclear because it is controlled by complex signalling pathways. This study aimed to investigate the mechanism underlying the effect of FGF2 on osteo/odontogenic differentiation of stem cells from the apical papilla (SCAP). SCAP were pretreated with conditioned media containing FGF2 for 1 week, followed by culturing in induced differentiation medium for another week. RNA sequencing (RNA-seq) combined with quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to evaluate the pathways affected by FGF2 in SCAP. Osteo/odontogenic differentiation of SCAP was determined using Alizarin red S staining, alkaline phosphatase staining, RT-qPCR, and western blotting. Pretreatment with FGF2 for 1 week increased the osteo/odontogenic differentiation ability of SCAP. RNA-seq and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that phosphatidylinositol 3-kinase (PI3K)/AKT signalling is involved in the osteogenic function of FGF2. RT-qPCR results indicated that SCAP expressed FGF receptors, and western blotting showed that p-AKT was reduced in FGF2-pretreated SCAP. The activation of the PI3K/AKT pathway partially reversed the stimulatory effect of FGF2 on osteo/odontogenic differentiation of SCAP. Our findings suggest that pretreatment with FGF2 enhances the osteo/odontogenic differentiation ability of SCAP by inhibiting the PI3K/AKT pathway.

Combined Effects of Fibroblast Growth Factor-2 and Carbonate Apatite Granules on Periodontal Healing: An In Vivo and In Vitro Study.

The aim of this study was to investigate in vivo and in vitro the effectiveness of the use of fibroblast growth factor (FGF)-2 with carbonate apatite (CO3Ap) on periodontal healing. Periodontal defects created in the maxillary first molars in rats were treated with FGF-2, CO3Ap, FGF-2 + CO3Ap or left unfilled. Healing was evaluated using microcomputed tomography, histological, and immunohistochemical analyses. In vitro experiments were performed to assess cellular behaviors and the expression of osteoblastic differentiation markers in MC3T3-E1 cells. At 4 weeks, the bone volume fraction in the FGF-2 + CO3Ap group was significantly greater than that in the CO3Ap group, but there was no significant difference from the FGF-2 group. The FGF-2 + CO3Ap group demonstrated greater new bone compared with the FGF-2 or CO3Ap group. The FGF-2 + CO3Ap group showed greater levels of osteocalcin-positive cells compared with the CO3Ap group, but there was no significant difference from the FGF-2 group. In vitro, the FGF-2 + CO3Ap group exhibited a greater extent of cell attachment and more elongated cells compared with the CO3Ap group. Compared with the CO3Ap group, the FGF-2 + CO3Ap group showed significantly higher viability/proliferation, but the expressions of Runx2 and Sp7 were reduced. The results indicated that the use of FGF-2 with CO3Ap enhanced healing in the periodontal defects. FGF-2 promoted cell attachment to and proliferation on CO3Ap and regulated osteoblastic differentiation, thereby contributing to novel bone formation.

The role of fibroblast growth factor-2 in modulating the differentiation of periodontal ligament and alveolar bone-derived stem cells

ObjectiveThis study examined how range concentrations of Fibroblast Growth Factor-2 (FGF-2) influence the differentiation and activity of human-derived periodontal ligament (hPDLSCs) and alveolar bone-derived stem cells (haBMSCs). DesignhPDLSCs and haBMSCs were cultured with varying concentrations of FGF-2 (0, 1, 2.5, 5, 10, 20 ng/mL) and monitored for osteogenic differentiation through alkaline phosphatase (ALP) activity and quantification of gene expression (qRT-PCR) for osteogenesis markers. Additionally, alizarin red staining and a hydroxyproline colorimetric assay evaluated and quantified osteogenic matrix mineralization and collagen deposition. Statistical analyses were performed using one-way ANOVA or two-way ANOVA for multiple comparisons between groups. ResultsAt low FGF-2 concentrations, hPDLSCs differentiated toward an osteogenic lineage, whereas higher concentrations of FGF-2 inhibited osteogenesis and promoted fibroblastic differentiation. The effect of FGF-2 at the lowest concentration tested (1 ng/mL) led to significantly higher ALP activity than osteogenically induced positive controls at early time points and equivalent RUNX2 expression at early and later time points. FGF-2 supplementation of haBMSC cultures was sufficient, at all concentrations, to increase ALP activity at an earlier time point. Mineralization of haBMSC cultures increased significantly within 5–20 ng/mL FGF-2 concentrations under basal growth media conditions (α-minimal essential medium supplemented with 15 % fetal bovine serum and 1 % penicillin/streptomycin). ConclusionsFGF-2 has a dual capacity in promoting osteogenic and fibroblastic differentiation within hPDLSCs contingent upon the dosage and timing of administration, alongside supporting osteogenic differentiation in haBMSCs. These findings underscore the need for precision growth factors dosing when considering the design of biomaterials for periodontal regeneration.

Lack of Direct Effects of Neurotrophic Factors in an In Vitro Model of Neuroinflammation.

Neuroinflammation is associated with several neurological disorders including temporal lobe epilepsy. Seizures themselves can induce neuroinflammation. In an in vivo model of epilepsy, the supplementation of brain-derived neurotropic factor (BDNF) and fibroblast growth factor-2 (FGF-2) using a Herpes-based vector reduced epileptogenesis-associated neuroinflammation. The aim of this study was to test whether the attenuation of the neuroinflammation obtained in vivo with BDNF and FGF-2 was direct or secondary to other effects, for example, the reduction in the severity and frequency of spontaneous recurrent seizures. An in vitro model of neuroinflammation induced by lipopolysaccharide (LPS, 100 ng/mL) in a mouse primary mixed glial culture was used. The releases of cytokines and NO were analyzed via ELISA and Griess assay, respectively. The effects of LPS and neurotrophic factors on cell viability were determined by performing an MTT assay. BDNF and FGF-2 were tested alone and co-administered. LPS induced a significant increase in pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and NO. BDNF, FGF-2, and their co-administration did not counteract these LPS effects. Our study suggests that the anti-inflammatory effect of BDNF and FGF-2 in vivo in the epilepsy model was indirect and likely due to a reduction in seizure frequency and severity.

Beneficial Effects of Fibroblast Growth Factor-1 on Retinal Pigment Epithelial Cells Exposed to High Glucose-Induced Damage: Alleviation of Oxidative Stress, Endoplasmic Reticulum Stress, and Enhancement of Autophagy.

Diabetic retinopathy (DR) severely affects vision in individuals with diabetes. High glucose (HG) induces oxidative stress in retinal cells, a key contributor to DR development. Previous studies suggest that fibroblast growth factor-1 (FGF-1) can mitigate hyperglycemia and protect tissues from HG-induced damage. However, the specific effects and mechanisms of FGF-1 on DR remain unclear. In our study, FGF-1-pretreated adult retinal pigment epithelial (ARPE)-19 cells were employed to investigate. Results indicate that FGF-1 significantly attenuated HG-induced oxidative stress, including reactive oxygen species, DNA damage, protein carbonyl content, and lipid peroxidation. FGF-1 also modulated the expression of oxidative and antioxidative enzymes. Mechanistic investigations showed that HG induced high endoplasmic reticulum (ER) stress and upregulated specific proteins associated with apoptosis. FGF-1 effectively alleviated ER stress, reduced apoptosis, and restored autophagy through the adenosine monophosphate-activated protein kinase/mammalian target of the rapamycin signaling pathway. We observed that the changes induced by HG were dose-dependently reversed by FGF-1. Higher concentrations of FGF-1 (5 and 10 ng/mL) exhibited increased effectiveness in mitigating HG-induced damage, reaching statistical significance (p < 0.05). In conclusion, our study underscores the promising potential of FGF-1 as a safeguard against DR. FGF-1 emerges as a formidable intervention, attenuating oxidative stress, ER stress, and apoptosis, while concurrently promoting autophagy. This multifaceted impact positions FGF-1 as a compelling candidate for alleviating retinal cell damage in the complex pathogenesis of DR.

FGF2 gene's antisense protein, NUDT6, plays a depressogenic role by promoting inflammation and suppressing neurogenesis without altering FGF2 signalling.

Fibroblast growth factor-2 (FGF2) is involved in the regulation of affective behaviour and shows antidepressant effects through the Akt and extracellular signal regulated kinase (ERK) 1/2 pathways. Nudix hydrolase 6 (NUDT6) protein is encoded from FGF2 gene's antisense strand and its role in the regulation of affective behaviour is unknown. Here, we overexpressed NUDT6 in the hippocampus and investigated its behavioural effects and the underlying molecular mechanisms affecting the behaviour. We showed that increasing hippocampal NUDT6 results in depression-like behaviour in rats without changing FGF2 levels or activating its downstream effectors, Akt and ERK1/2. Instead, NUDT6 acted by inducing inflammatory signalling, specifically by increasing S100 calcium binding protein A9 (S100A9) levels, activating nuclear factor-kappa B-p65 (NF-κB-p65), and elevating microglia numbers along with a reduction in neurogenesis. Our results suggest that NUDT6 could play a role in major depression by inducing a proinflammatory state. This is the first report of an antisense protein acting through a different mechanism of action than regulationof its sense protein. The opposite effects of NUDT6 and FGF2 on depression-like behaviour may serve as a mechanism to fine-tune affective behaviour. Our findings open up new venues for studying the differential regulation and functional interactions of sense and antisense proteins in neural function and behaviour, as well as in neuropsychiatric disorders. KEY POINTS: Hippocampal overexpression of nudix hydrolase 6 (NUDT6), the antisense protein of fibroblast growth factor-2 (FGF2), increases depression-like behaviour in rats. Hippocampal NUDT6 overexpression triggers a neuroinflammatory cascade by increasing S100 calcium binding proteinA9 (S100A9) expression and nuclear NF-κB-p65 translocation in neurons, in addition to microglial recruitment and activation. Hippocampal NUDT6 overexpression suppresses neurogenesis. NUDT6 exerts its actions without altering the levels or downstream signalling pathways of FGF2.

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.

A dual-omics approach on the effects of fibroblast growth factor-2 (FGF-2) on ventral tegmental area dopaminergic neurons in response to alcohol consumption in mice.

Harmful alcohol consumption is a major socioeconomic burden to the health system, as it can be the cause of mortality of heavy alcohol drinkers. The dopaminergic (DAergic) system is thought to play an important role in the pathogenesis of alcohol drinking behaviour; however, its exact role remains elusive. Fibroblast growth factor 2 (FGF-2), a neurotrophic factor, associated with both the DAergic system and alcohol consumption, may play an important role in DAergic neuroadaptations during alcohol abuse. Within this study, we aimed to clarify the role of endogenous FGF-2 on the DAergic system and whether there is a possible link to alcohol consumption. We found that lack of FGF-2 reduces the alcohol intake of mice. Transcriptome analysis of DAergic neurons revealed that FGF-2 knockout (FGF-2 KO) shifts the molecular fingerprint of midbrain dopaminergic (mDA) neurons to DA subtypes of the ventral tegmental area (VTA). In line with this, proteomic changes predominantly appear also in the VTA. Interestingly, these changes led to an altered regulation of the FGF-2 signalling cascades and DAergic pathways in a region-specific manner, which was only marginally affected by voluntary alcohol consumption. Thus, lack of FGF-2 not only affects the gene expression but also the proteome of specific brain regions of mDA neurons. Our study provides new insights into the neuroadaptations of the DAergic system during alcohol abuse and, therefore, comprises novel targets for future pharmacological interventions.

Fibroblast growth factor-21: preserving cell viability in diabetic neuropathy through the PI3K/AKT cellular pathway

Aim : This study aims to investigate the potential neuroprotective effects of fibroblast growth factor-21 (FGF21) on dorsal root ganglion (DRG) neurons under high glucose (HG) conditions, mimicking diabetic neuropathy. Specifically, we hypothesize that FGF21 enhances cell viability and reduces glucose-induced neuronal death via the activation of the phosphatidyl-inositol-3-kinase (PI3K)/AKT signaling pathway. Materials and Methods: Primary DRG neurons were cultured from laboratory models and exposed to HG concentrations to simulate diabetic conditions. Various concentrations of FGF21 were administered to the DRG neurons. Cell viability was assessed using the MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide), a widely used enzymatic method for determining cellular metabolic activity. The involvement of the PI3K /AKT signaling pathway in mediating the effects of FGF21 was also examined through biochemical assays and pathway inhibitors. Results: Administration of FGF21 to DRG neurons exposed to HG conditions significantly protected cell viability and reduced glucose-induced neuronal death (p &lt; 0.05). The protective effects of FGF21 were found to be dose-dependent, with higher concentrations showing more pronounced benefits. Furthermore, the activation of the PI3K /AKT signaling pathway was confirmed to play a crucial role in the neuroprotective mechanism of FGF21, as inhibition of this pathway attenuated the protective effects. Conclusion: This study demonstrates for the first time that FGF21 has a neuroprotective effect on DRG neuron survival in a diabetic neuropathy model. By activating the PI3K /AKT signaling pathway, FGF21 helps maintain cell viability and reduces glucose-related neuronal death. These findings provide a promising basis for the development of new therapeutic strategies for the treatment of diabetic neuropathy, leveraging the neuroprotective properties of FGF21.

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

ObjectiveHuman 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. DesignWe 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. ResultsFGF(+)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. ConclusionWe 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.

The Effects of Fibroblast Growth Factor-2 (FGF-2) on Achilles Tendon Injury

Category: Basic Sciences/Biologics; Ankle Introduction/Purpose: Achilles tendon defects are a challenging problem, and there is a need for new treatments. We investigated the use of Platelet-rich fibrin (PRF), a dense fibrin scaffold containing many growth factors and cytokines, for Achilles tendon injuries. The study found that PRF accelerates healing by promoting the proliferation and activation of tenocytes via FGF receptor/AKT signaling and TGF-β/SMAD3 signaling. While FGF-2, a growth factor in PRF, has been shown to promote tenocyte differentiation and proliferation, its effect on Achilles tendon injuries has not been reported. Therefore, this study aimed to investigate the effect of FGF-2 on Achilles tendon healing when administered alone and to determine its specific contribution to the healing process. Methods: We used a rat model of Achilles tendon defect. A 4-mm portion of the right Achilles tendon, 4 mm proximal to the calcaneal insertion, was resected to create a tendon defect. Gelatin hydrogel sheet (MedGel PI5) as a scaffold for PBS, FGF-2 (Rigroth®), and FGF receptor inhibitor (FGFRI: Pemigatinib) was placed into the gap before suturing it with nylon sutures. We observed HE-stained specimens at 200x and assessed histological healing by counting cells and vessels and grading cell morphology. The motor function was evaluated by the Basso, Beattie, and Bresnahan (BBB) score and the treadmill test. We compared the effects of FGF-2 on tenocytes isolated from rat Achilles tendons in the control, FGF2, and FGFRI groups. The proliferation and migration of tenocytes were measured by MTS assay and wound closure assay, respectively. Protein expression, such as Tenomodulin (Tnmd), Collagen Ⅰ, Ⅲ, and Screlaxis-A in cells, were evaluated by Western Blotting. Results: In the rat model, the number of cells, vessels and cell morphology scores at the defect sites increased in the FGF-2 group and decreased in the FGFRI group at 2 and 4 weeks postoperatively. In the motor functional evaluation, the FGF-2 group showed earlier improvement in the BBB score and the treadmill test compared to the control and FGFRI groups. The MTS assay showed that the number of viable cells was higher in the FGF-2 group and lower in the FGFRI group than in the control. Wound closure assay showed tenocyte migration was increased in the FGF-2 group and decreased in the FGFRI group. Regarding protein expression, Tnmd, Collagen I, III, and Screlaxis-A were increased in the FGF-2 group and decreased in the FGFRI group. Conclusion: In vivo, FGF-2 promoted healing of Achilles tendon injury, and FGFRI impeded it in terms of motor function and histology. Additionally, in vitro, FGF-2 promoted the proliferation and migration of tenocytes and enhanced extracellular matrix production, while FGFRI diminished these effects. Although native FGF-2 is produced at the injured site, further administration of FGF-2 accelerated Achilles tendon injury healing, while inhibiting the FGF receptor delayed recovery in this study. Therefore, FGF- 2 is very important in Achilles tendon injury healing and may promote recovery by enhancing angiogenesis, proliferation, and extracellular matrix production of tenocytes.

Fibroblasts are the most suitable cell source for regenerative medicine due to their high intracellular fibroblast growth factor 2 content

In our previous study, we found that dry-preserved multilayered fibroblast cell sheets promoted angiogenesis and wound healing in a mouse ulcer model by releasing high levels of intracellular fibroblast growth factor 2 (FGF2), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF), from dried cells. In the present study, to identify which cell types are suitable for human dry-preserved cell sheets (dry sheets), we compared the intracellular FGF2 levels in seven types of cells reported as cell sheets for clinical use or preclinical studies. FGF2 levels were high in mesenchymal cells, including human oral fibroblasts (HOFs) and human dermal fibroblasts (HDFs), human dental pulp stem cells (DPSCs), and human mesenchymal stem cells (MSCs); in contrast, FGF2 levels in human umbilical vascular endothelial cells (HUVECs), human skeletal muscle myoblasts (SkMMs), and human epidermal keratinocytes (HEKs) were remarkably low, approximately 25% those in fibroblasts. In addition, we prepared dry sheets from HOFs, DPSCs, and MSCs, and analyzed the growth factors released from each dry sheet upon rehydration. High levels of FGF2, HGF, and VEGF were detected in the eluate prepared by immersing each dry sheet. In particular, FGF2 and HGF were the most abundant in HOFs. An in vitro cell proliferation assay showed that these eluates significantly enhanced HUVEC proliferation compared to control cells. Furthermore, cells incubated with HOF eluate showed significantly higher cell proliferation than cells incubated with DPSC and MSC eluates. However, this proliferative response was significantly blocked by FGF2-neutralizing antibodies. These results demonstrate that growth factors released from human dry sheets have physiological activity and that this activity is mainly mediated by the effect of FGF2. Fibroblasts are ideal for the clinical application of dry-preserved cell sheets in humans owing to their high intracellular FGF2 content, fast cell proliferation, ease of handling, availability, and low culture costs, making them the most suitable cell source for regenerative medicine, with FGF2 release as the mechanism of action.

Evaluation of prevention and treatment effects of fibroblast growth factor-21 in BLM-induced pulmonary fibrosis.

Pulmonary fibrosis is a progressive and fatal fibrotic lung disease and associated with a high mortality rate. In the study, the prevention and treatment effects of fibroblast growth factor-21 (FGF-21) in bleomycin (BLM)-induced pulmonary fibrosis were investigated in vivo and vitro. In the prevention of pulmonary fibrosis studies, the results showed that interdict of FGF-21 could reduce the related gene and protein expression levels of pulmonary fibrosis. In addition, FGF-21 significantly reduced both the aggregation of inflammatory cells and deposition of collagen in the lung by histopathology. In therapy of pulmonary fibrosis studies, the results indicated that treatment with FGF-21 resulted in an amelioration of the pulmonary fibrosis in mice with reductions of the pathological score, collagen deposition and transforming growth factor (TGF)-β and α-smooth muscle actin (α-SMA) expressions in the lung tissues at fibrotic stage, and late administration was also able to reduce the degree of pulmonary fibrosis and even better than these in the prevention group. Furthermore, BLM-induced THP-1 macrophage model was verified using FGF-21; the result showed that FGF-21 decreased the related gene expression level of pulmonary fibrosis. FGF-21 may have preventive and therapeutic effects on BLM-induced pulmonary fibrosis via inhibiting myofibroblast differentiation and inflammatory. Thus, FGF-21 represents a potential drug for the prevention and treatment of pulmonary fibrosis.

FGF2 activity regulates operant alcohol self-administration and mesolimbic dopamine transmission

Fibroblast growth factor 2 (FGF2) is involved in the development and maintenance of the brain dopamine system. We previously showed that alcohol exposure alters the expression of FGF2 and its receptor, FGF receptor 1 (FGFR1) in mesolimbic and nigrostriatal brain regions, and that FGF2 is a positive regulator of alcohol drinking. Here, we determined the effects of FGF2 and of FGFR1 inhibition on alcohol consumption, seeking and relapse, using a rat operant self-administration paradigm. In addition, we characterized the effects of FGF2-FGFR1 activation and inhibition on mesolimbic and nigrostriatal dopamine neuron activation using in vivo electrophysiology. We found that recombinant FGF2 (rFGF2) increased the firing rate and burst firing activity of dopaminergic neurons in the mesolimbic and nigrostriatal systems and led to increased operant alcohol self-administration. In contrast, the FGFR1 inhibitor PD173074 suppressed the firing rate of these dopaminergic neurons, and reduced operant alcohol self-administration. Alcohol seeking behavior was not affected by PD173074, but this FGFR1 inhibitor reduced post-abstinence relapse to alcohol consumption, albeit only in male rats. The latter was paralleled by the increased potency and efficacy of PD173074 in inhibiting dopamine neuron firing. Together, our findings suggest that targeting the FGF2-FGFR1 pathway can reduce alcohol consumption, possibly via altering mesolimbic and nigrostriatal neuronal activity.

FGF2 Alleviates Microvascular Ischemia-Reperfusion Injury by KLF2-mediated Ferroptosis Inhibition and Antioxidant Responses.

An essential pathogenic element of acute limb ischemia/reperfusion (I/R) injury is microvascular dysfunction. The majority of studies indicates that fibroblast growth factor 2 (FGF2) exhibits protective properties in cases of acute I/R injury. Albeit its specific role in the context of acute limb I/R injury is yet unknown. An impressive post-reperfusion increase in FGF2 expression was seen in a mouse model of hind limb I/R, followed by a decline to baseline levels, suggesting a key role for FGF2 in limb survivability. FGF2 appeared to reduce I/R-induced hypoperfusion, tissue edema, skeletal muscle fiber injury, as well as microvascular endothelial cells (ECs) damage within the limb, according to assessments of limb vitality, Western blotting, and immunofluorescence results. The bioinformatics analysis of RNA-sequencing revealed that ferroptosis played a key role in FGF2-facilitated limb preservation. Pharmacological inhibition of NFE2L2 prevented ECs from being affected by FGF2's anti-oxidative and anti-ferroptosis activities. Additionally, silencing of kruppel-like factor 2 (KLF2) by interfering RNA eliminated the antioxidant and anti-ferroptosis effects of FGF2 on ECs. Further research revealed that the AMPK-HDAC5 signal pathway is the mechanism via which FGF2 regulates KLF2 activity. Data from luciferase assays demonstrated that overexpression of HDAC5 prevented KLF2 from becoming activated by FGF2. Collectively, FGF2 protects microvascular ECs from I/R injury by KLF2-mediated ferroptosis inhibition and antioxidant responses.

Modulatory role of mTOR in trophoblast adaptive response in the early stage of placentation in sheep.

Fibroblast growth factor-2 (FGF2) is essential for early placenta development in sheep. This study shows that the mechanistic target of rapamycin is the key modulator of trophoblast adaptive response under FGF2 modulation. During the early stage of placentation in sheep, normal conceptus development is affected by trophoblast cell functionality, whose dysregulation results in early pregnancy loss. Trophoblast metabolism is supported mainly by histotrophic factors, including fibroblast growth factor-2 (FGF2), which are involved in cell differentiation and function through the modulation of specific cellular mechanisms. The mechanistic target of rapamycin (mTOR) is known as a cellular 'nutrient sensor', but its downstream regulation remains poorly understood. The hypothesis was that during trophoblast development, the FGF2 effect is mediated by mTOR signalling pathway modulation. Primary trophoblast cells from 21-day-old sheep placenta were characterised and subjected to FGF2 and rapamycin treatment to study the effects on cell functionality and gene and protein expression profiles. The model showed mainly mononuclear cells with epithelial cell-like growth and placental morphological properties, expressing typical trophoblast markers. FGF2 promoted cell proliferation and migration under normal culture conditions, whereas mTOR inhibition reversed this effect. When the mTOR signalling pathway was activated, FGF2 failed to influence invasion activity. mTOR inhibition significantly reduced cell motility, but FGF2 supplementation restored motility even when mTOR was inhibited. Interestingly, mTOR inhibition influenced endocrine trophoblast marker regulation. Although FGF2 supplementation did not affect ovine placenta lactogen expression, as observed in the control, interferon-tau was drastically reduced. This study provides new insights into the mechanism underlying mTOR inhibitory effects on trophoblast cell functionality. In addition, as mTOR is involved in the expression of hormonal trophoblast markers, it may play a crucial role in early placenta growth and fetal-maternal crosstalk.

The early and late intervention effects of collagen-binding FGF2 on elastase-induced lung injury

IntroductionChronic obstructive pulmonary disease (COPD) has high morbidity and mortality, with no effective treatment at present. Emphysema, a major component of COPD, is a leading cause of human death worldwide. Fibroblast growth factor 2 (FGF2) is implicated in the pathogenesis of pulmonary emphysema and may play an important role in the lung repair process after injury, but concerns remain with respect to its effectiveness. ObjectiveIn the present work, we sought to determine how the timing (early and late intervention) of sustained-release FGF2 system administration impacted its effectiveness on a porcine pancreatic elastase (PPE)-induced lung injury mouse model. MethodsTo examine the early intervention efficiency of collagen-binding FGF2 (CBD-FGF2), mice received intratracheally nebulized CBD-FGF2 with concurrent intratracheal injection of PPE. To explore the late intervention effect, CBD-FGF2 was intratracheally aerosolized after PPE administration, and lungs were collected after CBD-FGF2 treatment for subsequent analysis. ResultIn response to PPE, mice had significantly increased alveolar diameter, collagen deposition and expression of inflammatory factors and decreased lung function indices and expression of alveolar epithelium markers. Our results indicate that CBD-FGF2 administration was able to prevent and repair elastase-induced lung injury partly through the suppression of the inflammatory response and recovery of the alveolar epithelium. The early use of CBD-FGF2 for the prevention of PPE-induced emphysema showed better results than late therapeutic administration against established emphysema. ConclusionThese data provide insight regarding the prospective role of a drug-based option (CBD-FGF2) for preventing and curing emphysema.

Braided suture-reinforced fibrous yarn bundles as a scaffold for tendon tissue engineering in extensor digitorum tendon repair

In this study, we intend to develop an effective tendon tissue engineering scaffold that can provide mechanical stability and tendon regeneration ability. Using a novel electrospinning process, a biodegradable suture was continuously covered with aligned polycaprolactone fibers in core/sheath structure to produce a single yarn. The single yarn was braided together to fabricate a multi yarn (MY) scaffold, which can be surface modified with oxygen plasma and conjugated with heparin. The fibroblast growth factor 2 (FGF2) was bound to MY through bioaffinity between heparin and FGF2 to generate a functional scaffold (MY-FGF2) suitable for extensor digitorum tendon (EDT) repair. The physico-chemical properties of the scaffolds were characterized throughout the modification steps using microscopy, spectroscopy and mechanical testing. In vitro static culture using rabbit tendon-derived fibroblasts (rTFs) indicates combined effects of FGF2 and fiber alignment can enhance cell proliferation and extracellular matrix synthesis rates, as well as fasten tendon maturation. The cytoskeleton staining further endorses aligned morphology of fibers direct cell growth and collagen fiber deposition along the fiber axial direction, mimicking native tendon features. The dynamic culture in a bioreactor under uniaxial cyclic tensile loading authenticates 5 % mechanical stimulation can further increase cell proliferation and tenogenic differentiation rates compared to static culture. After mechanical stimulation for 7 days in vitro, the MY-FGF2/rTFs construct was used for repair of EDT defects in rabbits. The retrieved MY-FGF2/rTFs sample 6-week post-implantation shows superior mechanical properties and tendon regeneration abilities over acellular MY-FGF2. Taken together, we demonstrate a combinatory approach with MY-FGF2 where chemical and physical cues provided by FGF2, fiber alignment and dynamic stimulation contribute to tendon regeneration with a specific focus on EDT repair.

FGF-2 enhances fibrogenetic changes in TGF-β2 treated human conjunctival fibroblasts.

The objective of the current study was to examine the effects of fibroblast growth factor-2 (FGF-2) on conjunctival fibrogenesis that was induced by the presence of transforming growth factor-β2 (TGF-β2). Two-dimension (2D) and three-dimension (3D) cultured human conjunctival fibroblasts (HconF) were used for this purpose. The 2D and 3D cultured HconF were characterized by transendothelial electrical resistance (TEER) and FITC dextran permeability measurements (2D), real-time metabolic analyses (2D), size and stiffness measurements (3D), and the mRNA expression of extracellular matrix molecules, their modulators, Tissue inhibitor of metalloproteinases and matrix metalloproteinases and ER-stress related genes (2D and 3D). FGF-2 significantly increased planar proliferation, as evidenced by TEER values and FITC dextran permeability, and shifted glucose metabolism to the energetic phenotype of 2D HconF cells, and the stiffness of the 3D spheroids, and these effects were further enhanced in the presence of TGF-β2. Analyses of the expression of possible candidate molecules involved in cell architecture and stress indicated that some additive effects caused by both factors were also recognized in some of these molecules. The findings reported herein indicate that the FGF-2, either along or additively with TGF- β2 increased the fibrogenetic changes on the plane as well as in the spatial space of HconF cells.

FGF2 positively regulates osteoclastogenesis via activating the ERK-CREB pathway

Fibroblast growth factor 2 (FGF2) plays crucial roles in the growth and development of several tissues. However, its function in bone homeostasis remains controversial. Here, we found that exogenous FGF2 supplementation inhibited the mineralization of bone marrow stromal cells (BMSCs), at least partially, via up-regulating the gene expression of osteoclastogenesis. The FGF receptor (FGFR) allosteric antagonist SSR128129E modestly, whereas the FGFR tyrosine kinase inhibitor AZD4547 significantly antagonized the effects of FGF2. Mechanistically, FGF2 stimulated ERK phosphorylation, and the ERK signaling inhibitor PD325901 strongly blocked FGF2 enhancement of osteoclastogenesis. Moreover, the phosphorylation of CREB was also activated in response to FGF2, thereby potentiating the interaction of p-CREB with the promoter region of Rankl gene. Notably, FGF2-deficient BMSCs exhibited higher mineralization capability and lower osteoclastogenic gene expression. Correspondingly, FGF2-knockout mice showed increased bone mass and attenuated expression of osteoclast-related markers, which were associated with moderate inhibition of the ERK signaling. In conclusion, FGF2 positively regulates osteoclastogenesis via stimulating the ERK-CREB pathway. These findings establish the importance of FGF2 in bone homeostasis, hinting the potential use of FGF2/ERK/CREB specific inhibitors to fight against bone-related disorders, such as osteoporosis.