Inflammation and infection associated with skin trauma present significant challenges for wound healing in clinical practice, underscoring the promising market prospects for innovative bioactive molecules. In this study, safflower seed oil was utilized as a drug carrier in combination with Keratinocyte growth factor-2 (KGF-2) to form a composite oil body. A nanoemulsion was prepared using the ultrasonication method, which was then mixed with a gel matrix to obtain the safflower seed oil and KGF-2 assembled nanoemulsion gel (OKNG). The physicochemical properties of the prepared OKNG, including particle size, drug loading, encapsulation efficiency, stability, morphology, moisture retention, degradation, sustained release, transdermal absorption, and activity, were thoroughly investigated. Furthermore, a full-thickness skin defect model was constructed to assess the wound healing ability through tissue staining analysis, and Real-time quantitative PCR (RT-qPCR) analysis was performed on the traumatic skin tissue related factors. The results of this study clearly indicate the potential of OKNG in promoting wound healing.

OBJECTIVE:Intervertebral Disc Degeneration (IVDD) is one of the leading causes of low back pain, significantly impacting both individuals and society. This study aimed to investigate the significance of macrophage infiltration and the role of macrophage-secreted platelet-derived growth factor-BB (PDGF-BB) in IVDD progression. METHODS:To confirm the protective function of macrophage-derived PDGF-BB on nucleus pulposus cells (NPCs), we employed Lysm-Cre transgenic mice to genetically ablate PDGF-B within the myeloid cells. Immunohistochemistry was utilized to detect the expression of glycolytic enzymes and pyroptosis-related proteins during the process of IVDD. Western blot, RT-PCR, ELISA and immunofluorescence were used to detect the protective effect of recombinant PDGF-BB on NPCs. RESULTS:Macrophage-derived PDGF-BB deficiency resulted in the loss of NPCs and the increased ossification of cartilage endplates during lumbar disc degeneration. Also, PDGF-BB deficiency triggered the inhibition of glycolytic enzymes' expression and the activation of pathways related to pyroptosis in the nucleus pulposus. Mechanistically, our results suggest that PDGF-BB predominantly conveys its protective influence on NPCs through the PDGF receptor- beta (PDGFR-β)/ thioredoxin-interacting protein pathway. CONCLUSIONS:The absence of PDGF-BB originating from macrophages expedites the advancement of IVDD, whereas the application of PDGF-BB treatment holds the potential for retarding intervertebral disc degeneration in the human body.

Cartilage endplate (CEP) degeneration has been considered as one of important factors related to intervertebral disc degeneration (IVDD). Previous researches have showed that Rac1 played a pivotal role in chondrocyte differentiation. However, the effect of Rac1 during the process of CEP degeneration remains unclear. Herein, we explored the effect of Rac1 on CEP degeneration and elucidated the underlying molecular mechanism. We found expression of Rac1-GTP increased in human-degenerated CEP tissue and IL-1β-stimulated rat endplate chondrocytes (EPCs). Our study revealed that Rac1 inhibitor NSC23766 treatment promoted the expression of collagen II, aggrecan and Sox-9, and decreased the expression of ADTAMTS5 and MMP13 in IL-1β-stimulated rat EPCs. Moreover, we also found that NSC23766 could suppress the activation of Wnt/β-catenin pathway, suggesting that the beneficial effects of Rac1 inhibition in EPCs are mediated through the Wnt/β-catenin signalling. Besides, puncture-induced rats models showed that NSC23766 played a protective role on CEP and disc degeneration. Collectively, these findings demonstrated that Rac1 inhibition delayed the EPCs degeneration and its potential mechanism may be associated with Wnt/β-catenin pathway regulation, which may help us better understand the association between Rac1 and CEP degeneration and provide a promising strategy for delaying the progression of IVDD.

Osteoarthritis (OA) is the most prevalent form of human arthritis which is characterized by the degradation of cartilage and inflammation. As a rare Sirt6 activator, cyanidin is the major component of anthocyanins commonly found in the Mediterranean diet, and increasing evidence has shown that cyanidin exhibits anti-inflammatory effects in a variety of diseases. However, the anti-inflammatory effects of cyanidin on OA have not been reported. In the present study, we identified that cyanidin treatment could strongly suppress the expression of NO, PGE2, TNF-α, IL-6, iNOs, COX-2, ADAMTS5 and MMP13, and reduce the degradation of aggrecan and collagen II in IL-1β-induced human OA chondrocytes, indicating the anti-inflammatory effect of cyanidin. Further investigation of the mechanism involved revealed that cyanidin could upregulate the Sirt6 level in a dose-dependent manner and Sirt6 silencing abolished the effect of cyanidin in IL-1β-stimulated human OA chondrocytes, indicating a stimulatory effect of cyanidin on Sirt6 activation. Meanwhile, we found that cyanidin could inhibit the NF-κB pathway in IL-1β-stimulated human OA chondrocytes and its effect may to some extent depend on Sirt6 activation, suggesting that cyanidin may exert a protective effect through regulating the Sirt6/NF-κB signaling axis. Moreover, the in vivo study also proved that cyanidin ameliorated the development of OA in surgical destabilization of the medial meniscus (DMM) mouse OA models. In conclusion, these results demonstrate that cyanidin may have therapeutic potential for the treatment of OA.

Osteoarthritis (OA), a common degenerative joint disease, is principally characterized by inflammation and destruction of cartilage. Nobiletin, an extract of the peel of citrus fruits, is known to have anti-inflammatory properties. However, the mechanisms by which nobiletin plays a protective role in osteoarthritis (OA) are not completely understood. In the present study, we investigated the anti-inflammatory effects of nobiletin in the progression of OA in both in vitro and in vivo experiments. Mouse chondrocytes were pretreated with nobiletin (0, 10, 20, 40 μM) for 24 h and then incubated with IL-1β (10 ng/ml, 24 h) in vitro. The generation of PGE2 and NO was evaluated by the Griess reaction and ELISAs. The protein expression of inducible nitric oxide synthase, matrix metalloproteinase-3, matrix metalloproteinase-13, A disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS5), cyclooxygenase-2, collagen II, and aggrecan was analyzed by Western blotting. Immunofluorescence and Western blot analysis were used to detect nuclear factor-κB (NF-κB) signaling molecules. Induction of proinflammatory and catabolic mediators by IL-1β stimulation of mouse chondrocytes could be partially blocked by treatment with nobiletin or ammonium pyrrolidine dithiocarbamate (an NF-κB inhibitor). Furthermore, our results indicated that nobiletin exhibited a therapeutic effect through active inhibition of the NF-κB signaling pathway. In a mouse model of OA, injection of nobiletin (20 mg/kg) every 2 days for 8 weeks after surgery inhibited cartilage destruction and synovitis. Taken together, our findings suggest that nobiletin may be a potential therapeutic agent for the treatment of OA.

Fibroblast growth factor (FGF) 13, a member of the FGF11 subfamily, is a kind of intracrine protein similar to other family members including FGF11, FGF12, and FGF14. Unlike classical FGF, FGF13 exerts its bioactivities independent of fibroblast growth factor receptors (FGFRs). However, the effect of exogenous administration of FGF13 still remains further investigated. In the present study, we established an Escherichia coli expression system for the large-scale production of FGF13 and then obtained two isoform proteins including recombinant human FGF13A (rhFGF13A) and rhFGF13B with a purity greater than 90% by column chromatography, respectively. Otherwise, soluble analysis indicated that both rhFGF13A and rhFGF13B expressed in E. coli BL21 (DE3) pLysS were soluble. Furthermore, cellular-based experiments demonstrated that rhFGF13A, rather than rhFGF13B, could promote the proliferation of NIH3T3 cells in the presence of heparin. Mechanistically, the mitogenic effect of FGF13 was mediated by activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK), but not p38. Moreover, blockage of FGFRs also significantly attenuated the mitogenic effects of rhFGF13A, implying that FGFRs are still related to FGF13. Thus, our research shows that exogenous FGF13 can act as secreted FGF to participate in cell signal transmission and heparin is still required as an ancillary cofactor for the mitogenic effects of FGF13, which may help people to discover more potential functions of FGF13 in cell life activities.

Studies regarding macroautophagic/autophagic regulation in endothelial cells (ECs) under diabetic conditions are very limited. Clinical evidence establishes an endothelial protective effect of metformin, but the underlying mechanisms remain unclear. We aimed to investigate whether metformin exerts its protective role against hyperglycemia-induced endothelial impairment through the autophagy machinery. db/db mice were treated with intravitreal metformin injections. Human umbilical vein endothelial cells (HUVECs) were cultured either in normal glucose (NG, 5.5 mM) or high glucose (HG, 33 mM) medium in the presence or absence of metformin for 72 h. We observed an obvious inhibition of hyperglycemia-triggered autophagosome synthesis in both the diabetic retinal vasculature and cultured HUVECs by metformin, along with restoration of hyperglycemia-impaired Hedgehog (Hh) pathway activity. Specifically, deletion of ATG7 in retinal vascular ECs of db/db mice and cultured HUVECs indicated a detrimental role of autophagy in hyperglycemia-induced endothelial dysfunction. Pretreatment with GANT61, a Hh pathway inhibitor, abolished the metformin-mediated downregulation of autophagy and endothelial protective action. Furthermore, GLI-family (transcription factors of the Hh pathway) knockdown in HUVECs and retinal vasculature revealed that downregulation of hyperglycemia-activated autophagy by the metformin-mediated Hh pathway activation was GLI1 dependent. Mechanistically, GLI1 knockdown-triggered autophagy was related to upregulation of BNIP3, which subsequently disrupted the association of BECN1/Beclin 1 and BCL2. The role of BNIP3 in BECN1 dissociation from BCL2 was further confirmed by BNIP3 overexpression or BNIP3 RNAi. Taken together, the endothelial protective effect of metformin under hyperglycemia conditions could be partly attributed to its role in downregulating autophagy via Hh pathway activation. Abbreviations: 3-MA = 3-methyladenine; 8×GLI BS-FL = 8×GLI-binding site firefly luciferase; AAV = adeno-associated virus; AAV-Cdh5-sh-Atg7 = AAV vectors carrying shRNA against murine Atg7 under control of murine Cdh5 promoter; AAV-Cdh5-sh-Gli1 = AAV vectors carrying shRNA against murine Gli1 under control of murine Cdh5 promoter; AAV-Cdh5-Gli1 = AAV vectors carrying murine Gli1 cDNA under the control of murine Cdh5 core promoter; ACAC = acetyl-CoA carboxylase; Ad-BNIP3 = adenoviruses harboring human BNIP3`; Ad-GLI1 = adenoviruses harboring human GLI1; Ad-sh-ATG7 = adenoviruses harboring shRNA against human ATG7; Ad-sh-BNIP3 = adenoviruses harboring shRNA against human BNIP3; Ad-sh-GLI = adenoviruses harboring shRNA against human GLI; AGEs = advanced glycation end products; ATG = autophagy-related; atg7flox/flox mice = mice bearing an Atg7flox allele, in which exon 14 of the Atg7 gene is flanked by 2 loxP sites; BafA1 = bafilomycin A1; BECN1 = beclin 1; CDH5/VE-cadherin = cadherin 5; CASP3 = caspase 3; CASP8 = caspase 8; CASP9 = caspase 9; ECs = endothelial cells; GAPDH = glyceraldehyde-3-phosphate dehydrogenase; GCL = ganglion cell layer; GFP-LC3B = green fluorescent protein labelled LC3B; HG = high glucose; Hh = Hedgehog; HHIP = hedgehog interacting protein; HUVECs = human umbilical vein endothelial cells; IB4 = isolectin B4; INL = inner nuclear layer; i.p. = intraperitoneal; MAP1LC3/LC3 = microtubule-associated protein 1 light chain 3; MAN = mannitol; MET = metformin; NG = normal glucose; ONL = outer nuclear layer; p-ACAC = phosphorylated acetyl-CoA carboxylase; PECAM1/CD31= platelet/endothelial cell adhesion molecule 1; PRKAA1/2 = protein kinase AMP-activated catalytic subunits alpha 1/2; p-PRKAA1/2 = phosphorylated PRKAA1/2; PTCH1 = patched 1; RAPA = rapamycin; RL = Renilla luciferase; SHH = sonic hedgehog; shRNA = short hairpin RNA; sh-PRKAA1/2 = short hairpin RNA against human PRKAA1/2; scrambled shRNA = the scrambled short hairpin RNA serves as a negative control for the target-specific short hairpin RNA, which has the same nucleotide composition as the input sequence and has no match with any mRNA of the selected organism database; SMO = smoothened, frizzled class receptor; sqRT-PCR = semi-quantitative RT-PCR; TEK/Tie2 = TEK receptor tyrosine kinase; Tek-Cre (+) mice = a mouse strain expressing Cre recombinase under the control of the promoter/enhancer of Tek, in a pan-endothelial fashion; TUNEL = terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling.

Expression of recombinant human fibroblast growth factor 18 (hFGF18) in mammalian cells and Escherichia coli has been extensively used for fundamental research and clinical applications, but they are difficult, expensive. The expression of recombinant proteins fused to oleosin protein have distinct advantages, such as safety, ease, low cost. So we have expressed hFGF18 fused to oleosin protein in the oil bodies of Arabidopsis thaliana (A. thaliana) and screen the proliferation effect of NIH3T3 cells. The vector of oleosinhFGF18 fusion gene was constructed and transformed into wild A. thaliana. Transformed A. thaliana lines were obtained by the floral dip method and confirmed using polymerase chain reaction (PCR). The PCR results indicated that the oleosin-hFGF18 fusion gene was integrated into the A. thaliana genome. The oil bodies expression of oleosin-hFGF18 was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blotting. The biological activity showed that oil bodies expressing oleosin-hFGF18 could stimulate the proliferation of NIH3T3 cells.

In the 22 member mammalian FGF family, FGF22 belongs to FGF7 subfamily, and its effects are largely confined to the brain and skin. To explore the functions of FGF22 on other tissues and develop a large-scale production of recombinant human FGF22 (rhFGF22) without a fusion tag, a plasmid encoding human FGF22 (pET3a-rhFGF22) was used to express rhFGF22 in E. coli BL21 (DE3) pLysS. A large amount of rhFGF22 inclusion body protein was obtained. A two-step denaturing method successfully solubilized rhFGF22, and it was refolded and then purified in one step via heparin affinity chromatography. A yield of 105 mg rhFGF22 with a purity of up to 95% was obtained from 100 g wet bacteria. It was found that the rhFGF22 had biological activity, since it effectively attenuated H2O2-induced human hepatic L02 cell death. Analysis by qRT-PCR and Western blot demonstrated that rhFGF22 protects L02 cells from H2O2-induced oxidative damage via suppression of mitochondrial apoptosis pathways. In conclusion, the strategy described in this paper may provide a novel means to solve the production of insoluble rhFGF22 and shine new light on its translational potential.

Fibroblast growth factor 9 (FGF9) is a heparin-binding growth factor, secreted by both mesothelial and epithelial cells, which participates in hair follicle regeneration, wound healing, and bone development. A suitable source of recombinant human FGF9 (rhFGF9) is needed for research into potential clinical applications. We present that expression of oleosin-rhFGF9 fusion protein in safflower (Carthamus tinctorius L.) seeds stimulates hair growth and wound healing.

The drug development of FGF7 has been restricted by its toxicity to the host, low expression, poor stability, and easy degradation. Recent studies have shown that Halo-tag-flanked recombinant human FGF7 can solve the problem of toxicity; however, its biological activity is unknown. This study aimed to explore the activity of Halo-rhFGF7 and rhFGF7 on acute liver injury in vitro and in vivo. The rhFGF7 is expressed with a N-terminal Halo-tag, followed by a tobacco etch virus (TEV) protease cleavage site, in Escherichia coli BL21 (DE3) pLysS in this study. The products could stimulate the proliferation of carbon tetrachloride-damaged L-O2 cells (normal human liver cells); they also inhibited cell apoptosis. Due to the use of the Halo, the protein could be tracked using fluorescence localization. Recombinant protein exerted a protective effect on the acute liver injury model in vitro and in vivo. The MTT assay and Western blot analysis showed that this protective effect is realized through various paths, including promoting proliferation, inhibiting cell apoptosis and anti-inflammatory. In conclusion, Halo-rhFGF7 and rhFGF7 displayed an excellent protective effect on acute liver injury. The present study provided an experimental basis and data support for further research on rhFGF7.

Fibroblast growth factor 18 (FGF18) is a member of the fibroblast growth factor family and important in cartilage growth and development. However, the mechanism by which FGF18 mediates its biological functions is still unclear. In our study, we expressed the rhFGF18 protein fused to a HaloTag, (Halo-rhFGF18). MTT assay results indicated that both rhFGF18 and Halo-rhFGF18 have similar biological activities in NIH3T3 cells. However, basic FGF and acidic FGF were more potent than both rhFGF18 and Halo-rhFGF18. Confocal imaging data indicated that the red fluorescence labeled Halo-rhFGF18 strongly bound to ATDC5 cells and stimulated their proliferation and differentiation, which suggests that glycosaminoglycans may be involved in mediating the biological effects of rhFGF18 in ATDC5 cells. Moreover, western blot results demonstrated that, in ATDC5 cells, ERK1/2 signaling is activated upon stimulation with rhFGF18. Our results may open doors for the use of rhFGF18 as a drug to promote cartilage growth.

Fusion protein technology is used in biotechnology and medical developments. In this study, recombinant fusion proteins from enterovirus A71 (EV-A71) subgenotype B5, Thailand were designed based two surface proteins (VP1 and VP2) and an internal protein (VP4), and named "VP0" (consisting of VP4-VP2) and "EV71" (consisting of VP4-VP2-VP1), respectively. The recombinant fusion proteins VP0 and EV71 were expressed in insect cells and successfully produced and secreted into the media. Both recombinant fusion proteins were shown to have immunogenic properties in BALB/c mice when formulated with Freund's complete/incomplete adjuvant (FA). Interestingly, EV71 formulated with FA- induced a level of IgG antibodies level similar to that induced by the recombinant protein VP1 formulated with FA (the positive control). Our results showed that VP1 alone is better at eliciting a strong cell-mediated immune response. Nontheless, EV71 formulated with FA was capable of inducing lymphocyte proliferation and increasing the cytokine-related mRNA expression levels of interferon-γ (IFN-γ), interleukin-2 (IL-2), and IL-10 in mice after immunization. Additionally, the number of CD4+ and CD8+ T lymphocyte cells after stimulation with purified EV71 in splenic cell culture showed highly specific CD4+ and CD8+ T-cell production. We suggest that EV71, which consists of VP4-VP2-VP1, could be used as the foundation for developing a novel recombinant fusion protein-based vaccine for EV-A71.

The expression of fibroblast growth factor 9 (FGF9) recombinant fusion protein in Carthamus tinctorius was used to identify its effect on hair regrowth and wound repair system in mice, providing a basis for C. tinctorius as a plant bioreactor, and establishing a foundation for commercial applications of FGF9 fusion protein in hair regrowth and wound repair. The identified pOTBar-oleosin-rhFGF9 plasmid was transformed into Agrobacterium tumefaciens EHA105 by freeze-thaw method, and the oleosin-rhFGF9 gene was transformed into safflower leaves by A. tumefaciens mediated method. Transgenic safflower seedlings were then obtained by tissue culture. After basta screening, transgenic T₃ safflower seeds were obtained by grafting method, PCR verification and propagation. The expression of oleosin-rhFGF9 was detected by Western blot, and the content of oleosin-rhFGF9 fusion protein was 0.09% by using ELISA quantitative method. It was observed that 60 μg·L⁻¹ transgenic safflower oil had better effect on promoting NIH/3T3 cells proliferation in a certain dose-dependent manner. Sixty C57BL/6 mice were used to establish alopecia model and wound model respectively, and then were randomly divided into control group (treated with PBS or saline), negative group (treated with wild type safflower seed oil bodies, 60 g·L⁻¹), positive group (treated with FGF9, 0.054 g·L⁻¹), low dose group (treated with transgenic safflower oil bodies, 10 g·L⁻¹) and high dose group (treated with transgenic safflower oil bodies, 60 g·L⁻¹). The skin of all above-mentioned mice models were coated with soft adhesive manner every other day, 100 μL/time. After 15 days, the mice skin was cut and embedded for histological analysis. The hair regrowth experimental results showed that the hair of mice grew well, and the mice in high dose group had bushy hair, with significant effect on regeneration hair number as compared with the positive group. The healing was obvious in wound experiment, with significant healing effect in positive group, high dose group and low dose group as compared to blank control group. Furthermore, high dose group remarkably showed a better and higher healing effect than the positive group at day 5. Oleosin-rhFGF9 was successfully transformed into safflower, and T₃ transgenic safflower oil bodies expressed oleosin-rhFGF9 fusion protein were obtained, with the role of promoting hair regeneration and wound repair in mice.

Fibroblast growth factor 6 (FGF6) known as hst-2 belonging to the FGF4 subfamily has extensive biological activities which include regulating cell proliferation, angiogenesis, as well as facilitating muscle regeneration. To further investigate the structural and biochemical effects of FGF6, we had firstly established a successful E. coli system for large-scale production of recombinant human FGF6 (rhFGF6) with remarkable biological activity. We performed renaturation of denatured rhFGF6 on a SP Sepharose column followed by washing with buffer containing 600 mM NaCl, and further purification on a Heparin Sepharose column. The yield of purified rhFGF6 was nearly 110 mg per liter of bacterial broth and the purity of rhFGF6 was up to 97% which was demonstrated by HPLC analysis. In vitro studies showed that the rhFGF6 protein could significantly stimulate the proliferation of NIH 3T3 cells and C2C12 myoblast cells, besides protecting H9c2 myocardial cells against H2O2 induced injury through MAPK-Caspase-3 dependent pathway. The approach described here could provide an efficient avenue to produce active rhFGF6.

Fibroblast growth factor-16 (FGF16) is a member of FGF9 subfamily, which plays key role in promoting mitosis and cell survival, and also involved in embryonic development, cell growth, tissue repair, morphogenesis, tumor growth, and invasion. However, the successful high-yield purification of recombinant human fibroblast growth factor-16 (rhFGF16) protein has not been reported. In addition, lung cancer is a major cause of cancer-related deaths, which threats people’s lives and its incidence has continued to rise. Learning pathways or proteins, which involved in lung tumor progression will contribute to the development of early diagnosis and targeted therapy. FGF16 promoted proliferation and invasion behavior of SKOV-3 ovarian cancer cells, whose function may be similar in lung cancer. The hFGF16 was cloned into pET-3d and expressed in Escherichia coli BL21 (DE3) pLysS. Finally, obtained two forms of FGF16 that exhibited remarkable biological activity and the purity is over 95%, meanwhile, the yield of soluble 130 mg/100 g and insoluble 240 mg/100 g. Experiments demonstrated FGF16 could promote proliferation of NCL-H460 cells by activating Akt, Erk1/2, and p38 MAPK signaling, whereas JNK had no significant effect. In total, this optimized expression strategy enables significant quantity and activity of rhFGF16, thereby meeting its further pharmacological and clinical usages.

Fibroblast growth factor 6 (FGF6) is a member of the fibroblast growth factor family (FGFs),induces a transduction signal preferentially via FGFR1 and FGFR4.It has been found,the human FGF6 participates in the proliferation and differentiation of muscle-derived cell lines,accumulated almost exclusively in the myogenic lineage,playing an important role in muscle repair and regeneration.At the same time,FGF6 is an important regulator of bone formation and bone remodeling;it also expressed in the heart,indicating that it can promote myocardial cell proliferation and protect the apoptosis of myocardial cells;in the adult testis FGF6 transcript is also detected,indicating that it plays a role in prostate cancer.At present,it remained to be further studied and confirmed the function and the related mechanisms of FGF6 in a variety of diseases,but its biological activity especially in muscle regeneration has important significance and great potential application.

Fibroblast growth factor (FGF) 9 has oncogenic activity and plays an important role in the development of ovarian, lung, prostate, and gastric cancers. In the present study, with the aim of reducing the cost of utilizing growth factors in cancer research, a simple and efficient method for the preparation of recombinant human (rh)FGF9 in Escherichia coli was established. The rhFGF9 fusion protein (6 × His-TEV-rhFGF9) and the native protein released by tobacco etch virus (TEV) protease were obtained using a Ni-NTA system, with > 95% purity. Both purified forms of rhFGF9, with and without fusion tags, significantly stimulated the proliferation of NIH3T3 cells. The FGF9 subfamily, including FGF9, FGF16, and FGF20, in addition to rhFGF16, rhFGF9, and rhFGF20, were shown to stimulate the proliferation and migration of HuH7 human hepatocellular carcinoma (HCC) cells. Mechanistic studies revealed that the stimulation of HuH7 cell proliferation and migration with rhFGF9 and rhFGF20 were associated with the activation of the extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB) pathways and matrix metalloproteinase-26 (MMP26). Inhibition of the ERK and NF-κB pathways blocked cell migration, and NF-κB was demonstrated to be regulated by ERK. Therefore, the present study demonstrates a simple method for the preparation of biologically active rhFGF9 protein. Furthermore, the results indicate that exogenous rhFGF9- and rhFGF20-activated ERK/NF-κB signal transduction pathways play important roles in the regulation of HCC cell proliferation and migration, and this discovery helps to find the potential for new solutions of the treatment of liver cancer.

The fibroblast growth factor (FGF) 9 subfamily is a member of the FGF family, including FGF9, 16, and 20, potentially sharing similar biochemical functions due to their high degree of sequence homology. Unlike other secreted proteins which have a cleavable N-terminal secreted signal peptide, FGF9/16/20 have non-cleaved N-terminal signal peptides. As an intercellular signaling molecule, they are involved in a variety of complex responses in animal development. Cardiogenesis is controlled by many members of the transcription factor family. Evidence suggests that FGF signaling, including the FGF9 subfamily, has a pretty close association with these cardiac-specific genes. In addition, recent studies have shown that the FGF9 subfamily maintains functional adaptation and survival after myocardial infarction in adult myocardium. Since FGF9/16/20 are secreted proteins, their function characterization in cardiac regeneration can promote their potential to be developed for the treatment of cardioprotection and revascularization. Here, we conclude that the FGF9 subfamily roles in cardiac development and maintenance of postnatal cardiac homeostasis, especially cardiac function maturation and functional maintenance of the heart after injury.

The beneficial effects of Fibroblast Growth Factor 21 (FGF21) on metabolic function and neuroprotection have been shown in earlier research. We have previously shown that the Dipeptidyl Peptidase 4 inhibitor, vildagliptin, also led to improved insulin sensitivity and brain function in the obese-insulin resistant condition. However, the comparative efficacy on the improvement of metabolic function and neuroprotection between FGF21 and vildagliptin in the obese-insulin resistant condition has never been investigated. Twenty-four male Wistar rats were divided into two groups, and received either a normal diet (ND, n=6) or a high fat diet (HFD, n=18) for 16 weeks. At week 13, the HFD-fed rats were divided into three subgroups (n=6/subgroup) to receive either a vehicle, recombinant human FGF21 (0.1mg/kg/day) or vildagliptin (3mg/kg/day), for four weeks. ND-fed rats were given a vehicle for four weeks. The metabolic parameters and brain function were subsequently investigated. The results demonstrated that the rats fed on HFD had obese-insulin resistance, increased systemic inflammation, brain mitochondrial dysfunction, increased brain apoptosis, impaired hippocampal plasticity, and demonstrated cognitive decline. FGF21 and vildagliptin effectively attenuated peripheral insulin resistance, brain mitochondrial dysfunction, brain apoptosis and cognitive decline. However, only FGF21 treatment led to significantly reduced body weight gain, visceral fat, systemic inflammation, improved hippocampal synaptic plasticity, enhanced FGF21 mediated signaling in the brain leading to prevention of early cognitive decline. These findings suggest that FGF21 exerts greater efficacy than vildagliptin in restoring metabolic function as well as brain function in cases of obese-insulin resistant rats.