Targeting long non-coding RNA NUDT6 enhances smooth muscle cell survival and limits vascular disease progression

Long non-coding RNAs (lncRNAs) orchestrate various biological processes and regulate the development of cardiovascular diseases. Their potential therapeutic benefit to tackle disease progression has recently been extensively explored. Our study investigates the role of lncRNA Nudix Hydrolase 6 (NUDT6) and its antisense target fibroblast growth factor 2 (FGF2) in two vascular pathologies: abdominal aortic aneurysms (AAA) and carotid artery disease. Using tissue samples from both diseases, we detected a substantial increase of NUDT6, whereas FGF2 was downregulated. Targeting Nudt6 in vivo with antisense oligonucleotides in three murine and one porcine animal model of carotid artery disease and AAA limited disease progression. Restoration of FGF2 upon Nudt6 knockdown improved vessel wall morphology and fibrous cap stability. Overexpression of NUDT6 in vitro impaired smooth muscle cell (SMC) migration, while limiting their proliferation and augmenting apoptosis. By employing RNA pulldown followed by mass spectrometry as well as RNA immunoprecipitation, we identified Cysteine and Glycine Rich Protein 1 (CSRP1) as another direct NUDT6 interaction partner, regulating cell motility and SMC differentiation. Overall, the present study identifies NUDT6 as a well-conserved antisense transcript of FGF2. NUDT6 silencing triggers SMC survival and migration and could serve as a novel RNA-based therapeutic strategy in vascular diseases.

Idebenone-loaded wound dressings promote diabetic wound healing through downregulation of Il1b, Nfkb genes and upregulation of Fgf2 gene

Reactive oxygen species (ROS) are overproduced in diabetic wounds and retard the healing response. Considering the antioxidative function of idebenone, its exogenous administration may quench excessive ROS and promote diabetic wound healing. In the current study, idebenone was loaded into polyvinyl alcohol (PVA) /calcium alginate scaffolds at three different concentrations of 1 w/w%, 2 w/w%, and 3 w/w%. Various in vitro experiments were performed to characterize the developed wound dressings. Cell viability assay showed that scaffolds loaded with 1 w/w% idebenone had significantly better protection under oxidative stress and exhibited higher cell viability. Therefore, the dressings containing 1% drug was chosen to treat diabetic wounds in rat model. Wound healing assay showed that the dressings loaded with 1% drug had significantly higher rate of wound size reduction, collagen deposition, and epithelial thickness. Gene expression study showed that wound healing was accompanied by modulation of inflammatory response, protection against oxidative stress, and increasing angiogenesis-related genes. This preliminary research suggests that PVA/calcium alginate/1% idebenone scaffolds can be considered as a potential treatment modality to treat diabetic wounds in the clinic. However, more extensive studies at gene and protein expression levels are required to understand its exact mechanism of healing effects.

FGFR2 Mutation p.Cys342Arg Enhances Mitochondrial Metabolism-mediated Osteogenesis via FGF/FGFR-AMPK-Erk1/2 Axis in Crouzon Syndrome

Background: Crouzon syndrome ([OMIM] #123500) caused by FGFR2 mutation is an autosomal dominant syndrome with craniosynostosis, the underlying mechanism of which remains obscure. Methods: First, whole exome sequencing was used to screen the possible pathogenic variant in two sporadic patients with Crouzon syndrome. The investigation of primary and secondary structures as well as the conservation analysis of FGFR2 mutation (p.Cys342Arg) was performed. Then, wild-type and mutant overexpression plasmids were constructed and transfected into pre-osteoblastic murine cell line MC3T3-E1 cells. Osteogenesis and mitochondrial metabolism were analyzed by CCK8, ALP staining and ALP activity, alizarin red staining, qRT-PCR, Western blot, seahorse assays and mitochondrial staining. The siRNA targeting FGFR2 and domain negative FGFR2 were designed for verification. Results: First, FGFR2 mutation (p.Cys342Arg) was detected in two sporadic Chinese Crouzon syndrome patients. FGFR2 p.Cys342Arg promoted the osteogenic differentiation of MC3T3-E1 cells through the upregulation of AMP-activated protein kinase (AMPK)-Erk1/2 signal pathway. Furthermore, FGFR2 p.Cys342Arg enhanced oxidative phosphorylation and converted mitochondrial fusion to the fission of MC3T3-E1, promoting osteogenic differentiation and craniosynostosis in Crouzon syndrome. Additionally, AMPK or Erk1/2 inhibitors delayed the cranial suture closure. Conclusion: FGFR2 mutation p.Cys342Arg promotes osteogenesis by enhancing mitochondrial metabolism-mediated via FGF/FGFR-AMPK-Erk1/2 axis, which indicates the potential of therapy targeting AMPK or Erk1/2 for syndromic craniosynostosis treatment.

FGF receptor inhibitor BGJ398 partially rescues osteoarthritis-like phenotype in older high molecular weight FGF2 transgenic mice via multiple mechanisms

We have used Basic Fibroblast Growth Factor (FGF2) transgenic mice as experimental models for human X-linked hypophosphatemia (XLH)-related degenerative osteoarthritis (OA) to investigate the pathogenesis of the disease and to test potential pharmacotherapies for treatment. This study tested the efficacy of BJG398, a small molecule fibroblast growth factor receptor tyrosine kinase (FGFRTK) inhibitor, to rescue the knee joint osteoarthritis phenotype in High Molecular Weight fibroblast growth factor 2 transgenic (HMWTgFGF2) mice. BJG398 was administered in vivo to 8-month-old female HMWTgFGF2 mice for six weeks. Histomorphometry, immunohistochemistry and micro-CT were used to examine the knee joints in BGJ398-treated and control mice. We assessed: Fibroblast Growth Factor 23 (FGF23) expression and FGFR1 activity; Matrix metalloproteinase 13 (MMP13) and Aggrecanase2 (ADAMTS5) expression; then signaling by SMAD1/5/8-pSMAD6, pERK1/2 and Runt-related transcription factor 2 (RUNX2). Using PrimePCR arrays, we identified a contributing role for major target genes in the TGFB/BMP2 signaling pathway that were regulated by BGJ398. BGJ398 inhibited HMWFGF2/FGF23-induced increase in bone morphogenic protein receptor-1, bone morphogenic protein-2 and 4 and Serine peptidase inhibitor, clade E, member 1. The results from Micro-CT and histology show BGJ398 treatment rescued the OA changes in subchondral bone and knee articular cartilage of HMWTgFGF2 mice. The gene expression and signal transduction results provide convincing evidence that HMWFGF2 generates OA through FGFRTK with characteristic downstream signaling that defines OA, namely: increased FGF23-FGFR1 activity with BMP-BMPR, activation of pSMAD1/5/8-RUNX2 and pERK signaling pathways, then upregulation of MMP13 and ADAMTS5 to degrade matrix. BGJ398 treatment effectively reversed these OA molecular phenotypes, providing further evidence that the OA generated by HMWFGF2 in the transgenic mice is FGFR-mediated and phenocopies the OA found in the Hyp mouse homolog of XLH with a spontaneous mutation in the Phex (phosphate regulating endopeptidase on the X chromosome) gene and human XLH-OA. Overall, the results obtained here explain how the pleotropic effects of FGF2 emanate from the different functions of HMW protein isoforms for cartilage and bone homeostasis, and the pathogenesis of XLH-degenerative osteoarthropathy. BGJ398 inhibits HMWFGF2-induced osteoarthritis via multiple mechanisms. These results provided important scientific evidence for the potential application of BGJ398 as a therapeutic agent for osteoarthritis in XLH.

Serine protease PRSS23 drives gastric cancer by enhancing tumor associated macrophage infiltration via FGF2

Serine proteases has been considered to be closely associated with the inflammatory response and tumor progression. As a novel serine protease, the biological function of PRSS23 is rarely studied in cancers. In this study, the prognostic significance of PRSS23 was analyzed in two-independent gastric cancer (GC) cohorts. PRSS23 overexpression was clinically correlated with poor prognosis and macrophage infiltration of GC patients. Loss-of-function study verified that PRSS23 plays oncogenic role in GC. RNA-seq, qRT-PCR, western blotting and ELISA assay confirmed that serine protease PRSS23 positively regulated FGF2 expression and secretion. Single-cell analysis and gene expression correlation analysis showed that PRSS23 and FGF2 were high expressed in fibroblasts, and highly co-expressed with the biomarkers of tumor associated macrophages (TAMs), cancer-associated fibroblasts (CAFs) and mesenchymal cells. Functional analysis confirmed PRSS23/FGF2 was required for TAM infiltration. Rescue assay further verified that PRSS23 promotes GC progression and TAM infiltration through FGF2. Survival analysis showed that high infiltration of M1-macrophage predicted favorable prognosis, while high infiltration level of M2-macrophage predicted poor prognosis in GC. Our finding highlights that PRSS23 promotes TAM infiltration through regulating FGF2 expression and secretion, thereby resulting in a poor prognosis.

[Therapeutic effects of alkaloids in Tibetan medicine Bangna (Aconiti Penduli et Aconiti Flavi Radix) on osteoarthritis rats and mechanisms]

This study aims to investigate the therapeutic effects of alkaloids in Tibetan medicine Bangna(Aconiti Penduli et Aconiti Flavi Radix) on osteoarthritis(OA) rats in vitro and in vivo and the underlying mechanisms. Chondrocytes were isolated from 2-3 week-old male SD rats and lipopolysaccharide(LPS) was used to induce OA in chondrocytes in vitro. Methyl thiazolyl tetrazolium(MTT) assay was used to investigate the toxicity of seven alkaloids(12-epi-napelline, songorine, benzoylaconine, aconitine, 3-acetylaconitine, mesaconitine, and benzoylmesaconine) to chondrocytes. Chondrocytes were classified into the control group, model group(induced by LPS 5 μg·mL~(-1) for 12 h), and administration groups(induced by LPS 5 μg·mL~(-1) for 12 h and incubated for 24 h). The protein expression of inflammatory factors cyclooxygenase-2(COX-2), inducible nitric oxide synthetase(iNOS), tumor necrosis factor-α(TNF-α), and interleukin-1β(IL-1β) in each group were detected by Western blot, and the protein expression of matrix metalloprotease-13(MMP-13), aggrecan, collagen Ⅱ, fibroblast growth factor 2(FGF2) by immunofluorescence staining. For the in vivo experiment, sodium iodoacetate was used to induce OA in rats, and the expression of MMP-13, TNF-α, and FGF2 in cartilage tissues of rats in each group was detected by immunohistochemistry. The results showed that the viability of chondrocytes could reach more than 90% under the treatment of the seven alkaloids in a certain dose range. Aconitine, 12-epi-napelline, songorine, 3-acetylaconitine, and mesaconitine could decrease the protein expression of inflammatory factors COX-2, iNOS, TNF-α and IL-1β compared with the model group. Moreover, 12-epi-napelline, aconitine, and mesaconitine could down-regulate the expression of MMP-13 and up-regulate the expression of aggrecan and collagen Ⅱ. In addition, compared with the model group and other Bangna alkaloids, 12-epi-napelline significantly up-regulated the expression of FGF2. Therefore, 12-epi-napelline was selected for the animal experiment in vivo. Immunohistochemistry results showed that 12-epi-napelline could significantly reduce the expression of MMP-13 and TNF-α in cartilage tissues, and up-regulate the expression of FGF2 compared with the model group. In conclusion, among the seven Bangna alkaloids, 12-epi-napelline can promote the repair of OA in rats by down-regulating the expression of MMP-13 and TNF-α and up-regulating the expression of FGF2.

Exercise attenuates myocardial fibrosis and increases angiogenesis-related molecules in the myocardium of aged rats

OBJECTIVES

The present study aimed to investigate the effect of two different exercise training protocols on myocardial fibrosis and the expression of some growth factors in aged rats.

METHOD

Twenty-four male Wistar rats were randomly assigned to high-intensity interval training (HIIT) group, continuous exercise training (CET) group, and the control group. After 6 weeks of experiment, mRNA levels of fibroblast growth factor-2 (FGF-2), vascular endothelial growth factor (VEGF), adropin proteins, and myocardial fibrosis were assessed.

RESULTS

HIIT and CET induced a significant increase in the FGF-2 and adropin and a decrease in the myocardial fibrosis in compared with the control group. HIIT induced a significant increase in the VEGF if compared with the control group. There was no significant difference between CET and control group.

CONCLUSION

Six weeks of HIIT and CET attenuated age-related myocardial fibrosis thereby an increase in angiogenesis-related molecules in cardiac and endothelial tissues.

FGF2 Is Protective Towards Cisplatin-Induced KGN Cell Toxicity by Promoting FTO Expression and Autophagy

It is widely known that chemotherapy-induced apoptosis of granulosa was the main reason for premature ovarian failure (POF). In addition, accumulating evidence has demonstrated that autophagy was involved in it. Studies before have reported that fibroblast growth factor-2 (FGF2) could attenuate cell death via regulating autophagy. In our previous study, FGF2 could decrease granulosa cell apoptosis in cisplatin-induced POF mice. Furthermore, obesity-associated protein [fat mass and obesity-associated protein (FTO)], which decreased significantly in POF mice, could inhibit cell apoptosis via activating autophagy. Moreover, downregulation of FTO could decrease the expression of paracrine factor FGF2. However, the relationship between FTO and FGF2 in granulosa cell autophagy is still unknown. In the present study, Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2-deoxyuridine (EdU) assays showed that exogenous addition of FGF2 could promote cisplatin-induced injured granulosa cell proliferation. Western blotting indicated that FGF2 could inhibit apoptosis of injured granulosa cells via autophagy. Inhibition of autophagy by chemicals suppressed the effect of FGF2 and promoted injured cell apoptosis. In addition, the expression of FTO was decreased in injured cells, and FGF2 addition could reverse it. Overexpression of FTO reduced injured cell apoptosis via activating the autophagy process. Our findings indicated that FGF2 activates autophagy by regulating the expression of FTO, thereby reducing the apoptosis of the injured cells.

Plant-derived human recombinant growth factors and serum albumin maintain stemness of human-induced pluripotent stem cells

Stem cells are an important therapeutic source for recovery and regeneration, as their ability of self-renewal and differentiation offers an unlimited supply of highly specialized cells for therapeutic transplantation. Growth factors and serum are essential for maintaining the characteristics of stem cells in culture and for inducing differentiation. Because growth factors are produced mainly in bacterial (Escherichia coli) or animal cells, the use of such growth factors raises safety concerns that need to be resolved for the commercialization of stem cell therapeutics. To overcome this problem, studies on proteins produced in plants have been conducted. Here, we describe the functions of plant-derived fibroblast growth factor 2 (FGF2) and human serum albumin in the maintenance and differentiation of human-induced pluripotent stem cells (hiPSCs). Plant-derived FGF2 and human epidermal growth factor EGF were able to differentiate hiPSCs into neural stem cells (NSCs). These NSCs could differentiate into neuronal and glial cells. Our results imply that culturing stem cells in animal-free culture medium, which is composed of plant-derived proteins, would facilitate stem cell application research, for example, for cell therapy, by reducing contamination risk.

Endogenous FGF-2 levels impact FGF-2/BMP-2 growth factor delivery dosing in aged murine calvarial bone defects

Bone repair in elderly mice has been shown to be improved or negatively impacted by supplementing the highly osteogenic bone morphogenetic protein-2 (BMP-2) with fibroblast growth factor-2 (FGF-2). To better predict the outcome of FGF-2 supplementation, we investigated whether endogenous levels of FGF-2 play a role in optimal dosing of FGF-2 for augmenting BMP-2 activity in elderly mice. In vivo calvarial bone defect studies in Fgf2 knockout mice with wildtype controls were conducted with the growth factors delivered in a highly localized manner from a biomimetic calcium phosphate/polyelectrolyte multilayer coating applied to a bone graft substitute. Endogenous FGF-2 levels were measured in old mice versus young and found to decrease with age. Optimal dosing for improving bone defect repair correlated with levels of endogenous FGF-2, with a larger dose of FGF-2 required to have a positive effect on bone healing in the Fgf2 knockout mice. The same dose in wildtype old mice, with higher levels of FGF-2, promoted chondrogenesis and increased osteoclast activity. The results suggest a personalized medicine approach, based on a knowledge of endogenous levels of FGF-2, should guide FGF-2 supplementation in order to avoid provoking excessive bone resorption and cartilage formation, both of which inhibited calvarial bone repair.

Identification of YAP1 as a novel downstream effector of the FGF2/STAT3 pathway in the pathogenesis of renal tubulointerstitial fibrosis

Chronic kidney disease is a global health problem and eventually develops into an end-stage renal disease (ESRD). It is now widely believed that renal tubulointerstitial fibrosis (TIF) plays an important role in the progression of ESRD. Renal tubular epithelial-mesenchymal transition (EMT) is an important cause of TIF. Studies have shown that FGF2 is highly expressed in fibrotic renal tissue, although the mechanism remains unclear. We found that FGF2 can activate STAT3 and induce EMT in renal tubular epithelial cells. STAT3, an important transcription factor, was predicted by the JASPAR biological database to bind to the promoter region of YAP1. In this study, STAT3 was shown to promote the expression of the downstream target gene YAP1 through transcription, promote EMT of renal tubular epithelial cells, and mediate the occurrence of renal TIF. This study provides a theoretical basis for the involvement of the FGF2/STAT3/YAP1 signaling pathway in the process of renal interstitial fibrosis and provides a potential target for the treatment of renal fibrosis.

Silencing of miR-497-5p inhibits cell apoptosis and promotes autophagy in Parkinson's disease by upregulation of FGF2

Parkinson's disease (PD) is a progressive neurodegenerative disorder with increasing prevalence in elderly individuals globally. MicroRNAs (miRNAs) have been confirmed to participate in the pathogenesis of various neurodegenerative diseases, including PD. MiR-497-5p is previously reported to be upregulated in PD. The present study was designed to further explore the function of miR-497-5p in PD. MiR-497-5p was significantly upregulated in 1-methyl-4-phenylpyridinium (MPP⁺ )-treated SH-SY5Y cells. Inhibition of miR-497-5p suppressed the cell apoptosis and triggered autophagy of MPP⁺ -treated SH-SY5Y cells. Further, miR-497-5p targeted fibroblast growth factor-2 (FGF2) in MPP⁺ -treated SH-SY5Y cells. Subsequently, rescue assays revealed that miR-497-5p regulated apoptosis and autophagy of MPP⁺ -treated SH-SY5Y cells by mediation on FGF2. In addition, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced PD mice models were established. The results exhibited that silencing of miR-497-5p improved mice bradykinesia, reduced cell apoptosis and induced autophagy in PD mice by FGF2. In conclusion, silencing of miR-497-5p alleviates PD by suppressing cell apoptosis and promoting autophagy in a FGF2 dependent manner, which will provide a novel target for Parkinson's disease management.

FGF-2 induces a failure of cell cycle progression in cells harboring amplified K-Ras, revealing new insights into oncogene-induced senescence

Paradoxically, oncogenes that drive cell cycle progression may also trigger pathways leading to senescence, thereby inhibiting the growth of tumorigenic cells. Knowledge of how these pathways operate, and how tumor cells may evade these pathways, is important for understanding tumorigenesis. The Y1 cell line, which harbors an amplification of the proto-oncogene Ras, rapidly senesces in response to the mitogen fibroblast growth factor-2 (FGF-2). To gain a more complete picture of how FGF-2 promotes senescence, we employed a multi-omics approach to analyze histone modifications, mRNA and protein expression, and protein phosphorylation in Y1 cells treated with FGF-2. Compared to control cells treated with serum alone, FGF-2 caused a delayed accumulation of acetylation on histone H4 and higher levels of H3K27me3. Sequencing analysis revealed decreased expression of cell cycle-related genes with concomitant loss of H3K27ac. At the same time, FGF-2 promoted the expression of p21, various cytokines, and MAPK-related genes. Nuclear envelope proteins, particularly lamin B1, displayed increased phosphorylation in response to FGF-2. Proteome analysis suggested alterations in cellular metabolism, as evident by modulated expression of enzymes involved in purine biosynthesis, tRNA aminoacylation, and the TCA cycle. We propose that Y1 cells senesce due to an inability to progress through the cell cycle, which may stem from DNA damage or TGFb signaling. Altogether, the phenotype of Y1 cells is consistent with rapidly established oncogene-induced senescence, demonstrating the synergy between growth factors and oncogenes in driving senescence and bringing additional insight into this tumor suppressor mechanism.

Proangiogenic Effect of 2A-Peptide Based Multicistronic Recombinant Constructs Encoding VEGF and FGF2 Growth Factors

Coronary artery disease remains one of the primary healthcare problems due to the high cost of treatment, increased number of patients, poor clinical outcomes, and lack of effective therapy. Though pharmacological and surgical treatments positively affect symptoms and arrest the disease progression, they generally exhibit a limited effect on the disease outcome. The development of alternative therapeutic approaches towards ischemic disease treatment, especially of decompensated forms, is therefore relevant. Therapeutic angiogenesis, stimulated by various cytokines, chemokines, and growth factors, provides the possibility of restoring functional blood flow in ischemic tissues, thereby ensuring the regeneration of the damaged area. In the current study, based on the clinically approved plasmid vector pVax1, multigenic constructs were developed encoding vascular endothelial growth factor (VEGF), fibroblast growth factors (FGF2), and the DsRed fluorescent protein, integrated via picornaviruses' furin-2A peptide sequences. In vitro experiments demonstrated that genetically modified cells with engineered plasmid constructs expressed the target proteins. Overexpression of VEGF and FGF2 resulted in increased levels of the recombinant proteins. Concomitantly, these did not lead to a significant shift in the general secretory profile of modified HEK293T cells. Simultaneously, the secretome of genetically modified cells showed significant stimulating effects on the formation of capillary-like structures by HUVEC (endothelial cells) in vitro. Our results revealed that when the multicistronic multigene vectors encoding 2A peptide sequences are created, transient transgene co-expression is ensured. The results obtained indicated the mutual synergistic effects of the growth factors VEGF and FGF2 on the proliferation of endothelial cells in vitro. Thus, recombinant multicistronic multigenic constructs might serve as a promising approach for establishing safe and effective systems to treat ischemic diseases.

Caffeine Inhibits Direct and Indirect Angiogenesis in Zebrafish Embryos

In this study, we report the effects of caffeine on angiogenesis in zebrafish embryos both during normal development and after exposure to Fibroblast Growth Factor 2 (FGF2). As markers of angiogenesis, we measured the length and width of intersegmental vessels (ISVs), performed whole-mount in situ hybridization with fli1 and cadh5 vascular markers, and counted the number of interconnecting vessels (ICVs) in sub-intestinal venous plexus (SIVP). In addition, we measured angiogenesis after performing zebrafish yolk membrane (ZFYM) assay with microinjection of fibroblast growth factor 2 (FGF2) and perivitelline tumor xenograft assay with microinjection of tumorigenic FGF2-overexpressing endothelial (FGF2-T-MAE) cells. The results showed that caffeine treatment causes a shortening and thinning of ISVs along with a decreased expression of the vascular marker genes and a decrease in the number of ICVs in the SIVP. Caffeine was also able to block angiogenesis induced by exogenous FGF2 or FGF2-producing cells. Overall, our results are suggestive of the inhibitory effect of caffeine in both direct and indirect angiogenesis.

RETRACTED: Healing potential of Spirulina platensis for skin wounds by modulating bFGF, VEGF, TGF-ß1 and α-SMA genes expression targeting angiogenesis and scar tissue formation in the rat model

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. The journal was alerted to an associated PubPeer post in which suspected duplicated features were identified within Figure 4 B1, and the histological image in Figure 3 A1 appears to have been previously published in another article, as detailed here: https://pubpeer.com/publications/E5658B7B735FF993AA795A5F14C086. The journal performed independent analysis and identified additional suspected image duplications between the images of mice in Figure 1 A+B and images of mice in Figure 6 A+B from Elbialy et al., BMC Veterinary Research (2020). The journal requested the authors provide an explanation to these concerns and associated raw data, but this request was not satisfactorily fulfilled. The Editor-in-Chief assessed the case and decided to retract the article.

Effect of Whole Tissue Culture and Basic Fibroblast Growth Factor on Maintenance of Tie2 Molecule Expression in Human Nucleus Pulposus Cells

Previous work showed a link between Tie2⁺ nucleus pulposus progenitor cells (NPPC) and disc degeneration. However, NPPC remain difficult to maintain in culture. Here, we report whole tissue culture (WTC) combined with fibroblast growth factor 2 (FGF2) and chimeric FGF (cFGF) supplementation to support and enhance NPPC and Tie2 expression. We also examined the role of PI3K/Akt and MEK/ERK pathways in FGF2 and cFGF-induced Tie2 expression. Young herniating nucleus pulposus tissue was used. We compared WTC and standard primary cell culture, with or without 10 ng/mL FGF2. PI3K/Akt and MEK/ERK signaling pathways were examined through western blotting. Using WTC and primary cell culture, Tie2 positivity rates were 7.0 ± 2.6% and 1.9 ± 0.3% (p = 0.004), respectively. Addition of FGF2 in WTC increased Tie2 positivity rates to 14.2 ± 5.4% (p = 0.01). FGF2-stimulated expression of Tie2 was reduced 3-fold with the addition of the MEK inhibitor PD98059 (p = 0.01). However, the addition of 1 μM Akt inhibitor, 124015-1MGCN, only reduced small Tie2 expression (p = 0.42). cFGF similarly increased the Tie2 expression, but did not result in significant phosphorylation in both the MEK/ERK and PI3K/Akt pathways. WTC with FGF2 addition significantly increased Tie2 maintenance of human NPPC. Moreover, FGF2 supports Tie2 expression via MEK/ERK and PI3K/Akt signals. These findings offer promising tools and insights for the development of NPPC-based therapeutics.

A Novel Volume-Stable Collagen Matrix Induces Changes in the Behavior of Primary Human Oral Fibroblasts, Periodontal Ligament, and Endothelial Cells

The aim of the present study was to investigate the influence of a novel volume-stable collagen matrix (vCM) on early wound healing events including cellular migration and adhesion, protein adsorption and release, and the dynamics of the hemostatic system. For this purpose, we utilized transwell migration and crystal violet adhesion assays, ELISAs for quantification of adsorbed and released from the matrix growth factors, and qRT-PCR for quantification of gene expression in cells grown on the matrix. Our results demonstrated that primary human oral fibroblasts, periodontal ligament, and endothelial cells exhibited increased migration toward vCM compared to control cells that migrated in the absence of the matrix. Cellular adhesive properties on vCM were significantly increased compared to controls. Growth factors TGF-β1, PDGF-BB, FGF-2, and GDF-5 were adsorbed on vCM with great efficiency and continuously delivered in the medium after an initial burst release within hours. We observed statistically significant upregulation of genes encoding the antifibrinolytic thrombomodulin, plasminogen activator inhibitor type 1, thrombospondin 1, and thromboplastin, as well as strong downregulation of genes encoding the profibrinolytic tissue plasminogen activator, urokinase-type plasminogen activator, its receptor, and the matrix metalloproteinase 14 in cells grown on vCM. As a general trend, the stimulatory effect of the vCM on the expression of antifibrinolytic genes was synergistically enhanced by TGF-β1, PDGF-BB, or FGF-2, whereas the strong inhibitory effect of the vCM on the expression of profibrinolytic genes was reversed by PDGF-BB, FGF-2, or GDF-5. Taken together, our data strongly support the effect of the novel vCM on fibrin clot stabilization and coagulation/fibrinolysis equilibrium, thus facilitating progression to the next stages of the soft tissue healing process.

FGF/FGFR Pathways in Multiple Sclerosis and in Its Disease Models

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system (CNS) affecting more than two million people worldwide. In MS, oligodendrocytes and myelin sheaths are destroyed by autoimmune-mediated inflammation, while remyelination is impaired. Recent investigations of post-mortem tissue suggest that Fibroblast growth factor (FGF) signaling may regulate inflammation and myelination in MS. FGF2 expression seems to correlate positively with macrophages/microglia and negatively with myelination; FGF1 was suggested to promote remyelination. In myelin oligodendrocyte glycoprotein (MOG)35-55-induced experimental autoimmune encephalomyelitis (EAE), systemic deletion of FGF2 suggested that FGF2 may promote remyelination. Specific deletion of FGF receptors (FGFRs) in oligodendrocytes in this EAE model resulted in a decrease of lymphocyte and macrophage/microglia infiltration as well as myelin and axon degeneration. These effects were mediated by ERK/Akt phosphorylation, a brain-derived neurotrophic factor, and downregulation of inhibitors of remyelination. In the first part of this review, the most important pharmacotherapeutic principles for MS will be illustrated, and then we will review recent advances made on FGF signaling in MS. Thus, we will suggest application of FGFR inhibitors, which are currently used in Phase II and III cancer trials, as a therapeutic option to reduce inflammation and induce remyelination in EAE and eventually MS.

[Regulation of bFGF and TGF-β2 in human scleral fibroblasts by the lumican gene mutation associated with myopia]

Objective: To investigate the regulation of basic fibroblast growth factor (bFGF) and transforming growth factor (TGF)-β2 in human scleral fibroblasts (HSFs) by the adenovirus-mediated Lumican gene mutation, and to illustrate the effect of this mutation on myopia. Methods: Experimental study. The HSFs were isolated and cultured from human scleral tissues. The 3rd to 5th generation HSFs were transduced with Lumican mutant (c.596T>C) adenovirus, Lumican wild-type adenovirus, and defective adenovirus as the mutant group, wild group, and negative control group, respectively. Untransduced HSFs were defined as control group. The operation was conducted three times in each group. The expression levels of Lumican, bFGF and TGF-β2 were detected by qPCR. Statistical analysis of gene expression differences between groups was performed by fold changes. The differences were analyzed by one way ANOVA combined with LSD-t test. Results: The expressions of Lumican in the mutant group and the wild group were 103.146-fold and 398.646-fold increased compared to the control group with significant difference (t=-16.641, -21.729; P<0.05). There was no statistical difference between the negative control group and the control group (t=1.689, P>0.05). The expressions of bFGF and TGF-β2 in the mutant group were 2.812-fold and 2.346-fold increased compared to the control group with significant difference, and higher than the other groups (t=-3.921, -4.851; P<0.05). There was no significant difference among the wild group, negative control group and control group (P>0.05). Conclusions: The Lumican mutation (c.596T>C) increased the expressions of bFGF and TGF-β2 in HSFs. It indicates that the Lumican mutation (c.596T>C) may change the metabolism of extracellular matrix in the sclera by regulating bFGF and TGF-β2 to participate in scleral remodeling during the process of myopia. (Chin J Ophthalmol, 2021, 57:277-283).

AAV2-mediated and hypoxia response element-directed expression of bFGF in neural stem cells showed therapeutic effects on spinal cord injury in rats

Neural stem cell (NSCs) transplantation has been one of the hot topics in the repair of spinal cord injury (SCI). Fibroblast growth factor (FGF) is considered a promising nerve injury therapy after SCI. However, owing to a hostile hypoxia condition in SCI, there remains a challenging issue in implementing these tactics to repair SCI. In this report, we used adeno-associated virus 2 (AAV2), a prototype AAV used in clinical trials for human neuron disorders, basic FGF (bFGF) gene under the regulation of hypoxia response element (HRE) was constructed and transduced into NSCs to yield AAV2-5HRE-bFGF-NSCs. Our results showed that its treatment yielded temporally increased expression of bFGF in SCI, and improved scores of functional recovery after SCI compared to vehicle control (AAV2-5HRE-NSCs) based on the analyses of the inclined plane test, Basso-Beattie-Bresnahan (BBB) scale and footprint analysis. Mechanistic studies showed that AAV2-5HRE-bFGF-NSCs treatment increased the expression of neuron-specific neuronal nuclei protein (NeuN), neuromodulin GAP43, and neurofilament protein NF200 while decreased the expression of glial fibrillary acidic protein (GFAP) as compared to the control group. Further, the expressions of autophagy-associated proteins LC3-II and Beclin 1 were decreased, whereas the expression of P62 protein was increased in AAV2-5HRE-bFGF-NSCs treatment group. Taken together, our data indicate that AAV2-5HRE-bFGF-NSCs treatment improved the recovery of SCI rats, which is accompanied by evidence of nerve regeneration, and inhibition of SCI-induced glial scar formation and cell autophagy. Thus, this study represents a step forward towards the potential use of AAV2-5HRE-bFGF-NSCs for future clinical trials of SCI repair.

Co-transfection with BMP2 and FGF2 via chitosan nanoparticles potentiates osteogenesis in human adipose-derived stromal cells in vitro

OBJECTIVE

To investigate if co-transfection of human bone morphogenetic protein 2 (BMP-2, BMP2) and human fibroblast growth factor 2 (FGF2, FGF2) via chitosan nanoparticles promotes osteogenesis in human adipose tissue-derived stem cells (ADSCs) in vitro.

MATERIALS AND METHODS

Recombinant BMP2 and/or FGF2 expression vectors were constructed and packaged into chitosan nanoparticles. The chitosan nanoparticles were characterized by atomic force microscopy. Gene and protein expression levels of BMP-2 and FGF2 in ADSCs in vitro were evaluated by real-time polymerase chain reaction (PCR), western blot, and enzyme-linked immunosorbent assay. Osteocalcin (OCN) and bone sialoprotein (BSP) gene expression were also evaluated by real-time PCR to assess osteogenesis.

RESULTS

The prepared chitosan nanoparticles were spherical with a relatively homogenous size distribution. The BMP2 and FGF2 vectors were successfully transfected into ADSCs. BMP-2 and FGF2 mRNA and protein levels were significantly up-regulated in the co-transfection group compared with the control group. OCN and BSP mRNA levels were also significantly increased in the co-transfection group compared with cells transfected with BMP2 or FGF2 alone, suggesting that co-transfection significantly enhanced osteogenesis.

CONCLUSIONS

Co-transfection of human ADSCs with BMP2/FGF2 via chitosan nanoparticles efficiently promotes the osteogenic properties of ADSCs in vitro.

Therapeutic effects of blocking β-catenin against hepatocellular carcinoma-induced activation of inflammation, fibrosis and tumor invasion

Destructive effects of hepatocellular carcinoma (HCC) is enhanced by many cellular mechanisms including activation of fibrosis, inflammation and tumor invasion. Therefore, this study was conducted to investigate the therapeutic effects of iCRT14, β-catenin blocker, on HCC. In addition, the molecular effects of iCRT14 will be investigated on inflammation, fibrosis and tumor invasion pathways. After inducting HCC in rats, hepatic tissues were used for determination of the expression of β-catenin, nuclear factor (NF)κB, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, matrix metalloproteinase (MMP)9, transforming growth factor (TGF)-β1, fibroblast growth factor (FGF)-2 and integrin-β6. Hepatic tissues were stained with hematoxylin/eosin and with anti-Ki67. Results revealed that iCRT14 significantly increased the survival percent of HCC rats, reduced both α-fetoprotein and average number of nodules. In parallel, hepatic sections from HCC rats stained with hematoxylin/eosin revealed vacuolated cytoplasm and necrotic nodules, which were attenuated by treatment with iCRT14. Finally, treating HCC rats with iCRT14 resulted in reduction of the expression of NFκB, TNF-α, IL-1β, TGF-β1, MMP9, FGF-2 and integrin-β6. In conclusion, iCRT14 treatment exhibited antitumor effects against HCC through impairing β-catenin signaling pathway. iCRT14 suppressed liver tissue inflammation, fibrosis and angiogenesis, possibly via reducing expression of NFκB, TNF-α, IL-1β, TGF-β1, MMP-9, FGF-2.

Growth Factors VEGF-A165 and FGF-2 as Multifunctional Biomolecules Governing Cell Adhesion and Proliferation

Vascular endothelial growth factor-A165 (VEGF-A165) and fibroblast growth factor-2 (FGF-2) are currently used for the functionalization of biomaterials designed for tissue engineering. We have developed a new simple method for heterologous expression and purification of VEGF-A165 and FGF-2 in the yeast expression system of Pichia pastoris. The biological activity of the growth factors was assessed in cultures of human and porcine adipose tissue-derived stem cells (ADSCs) and human umbilical vein endothelial cells (HUVECs). When added into the culture medium, VEGF-A165 stimulated proliferation only in HUVECs, while FGF-2 stimulated the proliferation of both cell types. A similar effect was achieved when the growth factors were pre-adsorbed to polystyrene wells. The effect of our recombinant growth factors was slightly lower than that of commercially available factors, which was attributed to the presence of some impurities. The stimulatory effect of the VEGF-A165 on cell adhesion was rather weak, especially in ADSCs. FGF-2 was a potent stimulator of the adhesion of ADSCs but had no to negative effect on the adhesion of HUVECs. In sum, FGF-2 and VEGF-A165 have diverse effects on the behavior of different cell types, which maybe utilized in tissue engineering.

Genetic Variants of ANGPT1, CD39, FGF2 and MMP9 Linked to Clinical Outcome of Bevacizumab Plus Chemotherapy for Metastatic Colorectal Cancer

Angiogenesis pathway genes show substantial genetic variability causing inter-individual differences in responses to anti-angiogenic drugs. We examined 20 single nucleotide polymorphisms (SNPs) in 13 of these genes to predict tumour response and clinical outcome measured as progression free survival (PFS) and overall survival (OS) in 57 patients with metastatic colorectal cancer (mCRC) given bevacizumab plus chemotherapy. SNPs were detected (iPLEX® Assay) in genomic DNA extracted from formalin-fixed paraffin-embedded tumour specimens. The variant allele CD39 rs11188513 was associated with a good tumour response (p = 0.024). Patients homozygous for the wild-type allele FGF2 rs1960669 showed a median PFS of 10.95 months versus 5.44 months for those with at least one variant allele-A (HR 3.30; 95% CI: 1.52–7.14; p = 0.001). Patients homozygous for wild-type MMP9 rs2236416 and rs2274755 showed a median PFS of 9.48 months versus 6 and 6.62 months, respectively, for those with at least one variant allele (p = 0.022, p = 0.043, respectively). OS was also lengthened to 30.92 months (p = 0.034) in carriers of wild-type ANGPT1 rs2445365 versus 22.07 months for those carrying at least one variant allele-A. These gene variants were able to predict clinical outcome and tumour response in mCRC patients given bevacizumab-based therapy.