Concentrations Of Fibroblast Growth Factor Research Articles

#1443 Bone and mineral metabolism in patients with nephropathic cystinosis as a function of age and eGFR

Abstract Background and Aims Cystinosis-associated metabolic bone disease (CMBD) is a major challenge in the treatment of patients with infantile nephropathic cystinosis (NC). Study data are limited due to small case numbers, lack of adults or patients on renal replacement therapy and/or inadequate assessment of bone health. Method We investigated markers for CMBD in all age groups (1-44 years; 61% children) and CKD stages 1-5D/T in the largest NC cohort to date with 103 German and Austrian NC patients. Skeletal comorbidity and concentrations of fibroblast growth factor 23 (FGF23), the osteoblast marker bone-specific alkaline phosphatase (BAP), the bone remodeling inhibitor sclerostin, the osteoclast marker tartrate-resistant acid phosphatase 5b (TRAP5b), the soluble receptor activator of nuclear factor kappa B ligand (sRANKL), osteoprotegerin (OPG) and the sRANKL/OPG ratio as surrogates for the regulation of osteoclastogenesis by osteoblasts were determined by ELISA, converted into age- and sex-specific z-scores and compared as a function of eGFR. Multivariable regression analyses were used to identify specific influencing factors associated with biochemical and clinical findings in pre-transplant NC patients. Results Skeletal complications occurred in two-thirds of patients, with the risk being five times higher in adults than in children. Pediatric and adult NC patients with CKD stages 1-4 showed hypophosphatemia and hypocalcemia associated with suppressed FGF23 and PTH levels and elevated BAP concentrations. This was associated with age, eGFR and treatment with phosphate and active vitamin D, suggesting more vigorous treatment of Fanconi syndrome in pre-transplant patients. As indicated by the increased TRAP5b and decreased sRANKL/OPG ratio, osteoclast activity was increased despite counterregulation by osteoblasts, which in conjunction with increased sclerostin activity may have contributed to the progressive bone loss and skeletal comorbidity in our patient cohort. Conclusion Bone health in NC progressively deteriorates with age, largely due to persistent rickets/osteomalacia associated with inadequate treatment of Fanconi syndrome and increased osteoclast activity despite osteoblast counterregulation via OPG/RANKL. Our data suggest that a primary osteoclast defect in NC promotes increased bone resorption, limiting maximal bone mass and leading to progressive bone loss and increased skeletal comorbidity.

Serum fibroblast growth factor-2 levels complement vital biomarkers for diagnosing heart failure

BackgroundEarly diagnosis of atrial fibrillation is important as it is crucial for improving patient outcomes. Fibroblast growth factor-2 (FGF2) may serve as a diagnostic biomarker for heart failure due to its ability to promote cardiac fibrosis and hypertrophy; however, the relationship between FGF2 concentration and heart failure is unclear. Therefore, this study aimed to explore whether FGF2 could aid in distinguishing patients with heart failure from healthy controls and those with dyspnea without heart failure. Additionally, to evaluate the possible correlation between serum FGF2 levels and its diagnostic parameters in patients with heart failure.MethodsPlasma FGF2 concentration was measured in 114 patients with a complaint of dyspnea (enrolled in the study between January 2022 and August 2022). Based on heart failure diagnosis, the patients were assigned to three groups, as follows: heart failure (n = 80), non-heart-failure dyspnea (n = 34), and healthy controls (n = 36), following physical examination. Possible correlations between serum FGF2 levels and other prognostic parameters in patients with heart failure were analyzed.ResultsSerum FGF2 levels were higher in patients with heart failure (125.60 [88.95, 183.40] pg/mL) than in those with non-heart-failure dyspnea (65.30 [28.85, 78.95] pg/mL) and healthy controls (78.90 [60.80, 87.20] pg/mL) (p < 0.001). Receiver operating characteristic curve analysis identified FGF2 concentration as a significant predictor in heart failure diagnosis, with an area under the curve of 0.8693 (p < 0.0001). Importantly, in the heart failure group, serum FGF2 concentrations correlated with key prognostic parameters for heart failure, such as reduced left ventricular ejection fraction and elevated serum levels of N-terminal pro-B-type natriuretic peptide.ConclusionsElevated serum FGF2 level is strongly associated with an increased risk of heart failure and could serve as a useful biomarker to complement vital diagnostic parameters for heart failure.

The Ip6k1 and Ip6k2 Kinases Are Critical for Normal Renal Tubular Function.

Kidneys are gatekeepers of systemic inorganic phosphate balance because they control urinary phosphate excretion. In yeast and plants, inositol hexakisphosphate kinases (IP6Ks) are central to regulate phosphate metabolism, whereas their role in mammalian phosphate homeostasis is mostly unknown. We demonstrate in a renal cell line and in mice that Ip6k1 and Ip6k2 are critical for normal expression and function of the major renal Na + /Pi transporters NaPi-IIa and NaPi-IIc. Moreover, Ip6k1/2-/- mice also show symptoms of more generalized kidney dysfunction. Thus, our results suggest that IP6Ks are essential for phosphate metabolism and proper kidney function in mammals. Inorganic phosphate is an essential mineral, and its plasma levels are tightly regulated. In mammals, kidneys are critical for maintaining phosphate homeostasis through mechanisms that ultimately regulate the expression of the Na + /Pi cotransporters NaPi-IIa and NaPi-IIc in proximal tubules. Inositol pyrophosphate 5-IP 7 , generated by IP6Ks, is a main regulator of phosphate metabolism in yeast and plants. IP6Ks are conserved in mammals, but their role in phosphate metabolism in vivo remains unexplored. We used in vitro (opossum kidney cells) and in vivo (renal tubular-specific Ip6k1/2-/- mice) models to analyze the role of IP6K1/2 in phosphate homeostasis in mammals. In both systems, Ip6k1 and Ip6k2 are responsible for synthesis of 5-IP 7 . Depletion of Ip6k1/2 in vitro reduced phosphate transport and mRNA expression of Na + /Pi cotransporters, and it blunts phosphate transport adaptation to changes in ambient phosphate. Renal ablation of both kinases in mice also downregulates the expression of NaPi-IIa and NaPi-IIc and lowered the uptake of phosphate into proximal renal brush border membranes. In addition, the absence of Ip6k1 and Ip6k2 reduced the plasma concentration of fibroblast growth factor 23 and increased bone resorption, despite of which homozygous males develop hypophosphatemia. Ip6k1/2-/- mice also show increased diuresis, albuminuria, and hypercalciuria, although the morphology of glomeruli and proximal brush border membrane seemed unaffected. Depletion of renal Ip6k1/2 in mice not only altered phosphate homeostasis but also dysregulated other kidney functions.

Comparison between 100% autologous serum and 100% platelet‐rich plasma eye drops and their impact on the treatment efficacy of dry eye in primary Sjogren syndrome

Purpose: The aim of the study was to compare the difference in the composition of 100% autologous serum (AS) and 100% platelet‐rich plasma (PRP) eye drops and assess their impact on the clinical out‐comes after the treatment of severe dry eye (DE) in primary Sjogren Syndrome patients (pSS).Methods: 22 patients with severe DE in pSS were treated with 100% AS (22 eyes) and 100% PRP (22 eyes) eye drops 5 times per day as monotherapy. The quantification of growth factors (GFs) as fibroblast growth factor (FGF), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), platelet‐derived growth factor (PDGF), nerve growth factor (NGF), transforming growth factor (TGF‐b), insulin‐like growth factor(IGF), fibronectin and substance P in hemoderivates was performed. The main outcomes: Ocular Surface Disease Index (OSDI), Best Corrected Visual Acuity (BCVA), the Schirmer test, tear break‐up time (TBUT), corneal and conjunctival staining according to the Oxford scale, conjunctival hyperaemia and Meibomian gland parameters. The results were compared at the baseline, 1 and 3 months after the treatment. The clinical results were correlated with the concentration of GFs.Results: Significant differences were observed in the concentration of FGF, EGF, fibronectin, VEGF, PDGF AB, NGF, PDGF, substance P, TGF‐β in PRP compared to AS. There was a statistically significant improvement in BCVA, the Schirmer test, TBUT, Meibomian gland parameters, and the reduction of the OSDI scores, Oxford staining and conjunctiva hyperaemia in each group. There were many correspondences between the level of GFs and the mean change of the clinical outcomes. No adverse events were reported.Conclusions: Despite the fact that blood derivatives differ in their composition, they seem to be effective, safe in the treatment of severe DE in pSS patients. The signs and symptoms of DE were reduced in both groups. The obtained clinical results and the composition of hemoderivates may indicate the superiority of PRP in relieving the signs and symptoms of DE in pSS patients.

Analysis of the Effect of Substrate Stiffness on the Efficacy of Fibroblast Growth Factor 2 and Bone Morphogenetic Protein 4 in Inducing Pro-Regenerative Astrocyte Phenotype: A Research Protocol

Introduction: Astrocytes are glial cells essential for neuronal development and repair and are thus a highly promising target for regenerative therapies for neurodegenerative disease. Neurodegeneration has been connected to the degradation of extracellular matrix (ECM) components. ECM's structural properties, such as stiffness, influence the phenotypic outcomes of growing cells. Notably, astrocytes are induced into an A2 (pro-regenerative) phenotype when grown on stiff substrates or exposed to specific signalling molecules, particularly fibroblast growth factor 2 (FGF-2) and bone morphogenetic protein 4 (BMP-4). Given that the ECM can bind and sequester growth factors, it is possible that matrix stiffness may modulate the efficacy of these molecules. Methods: In this in vitro study, rat primary cortical astrocytes will be cultured on soft and stiff substrates and exposed to varying amounts of FGF-2 and BMP-4. This study aims to determine the effect of substrate stiffness on the efficacy of FGF-2 and BMP-4 in promoting pro-regenerative phenotype. Cell proliferation and glial fibrillary acidic protein (GFAP) expression are key indicators of reactive astrocytes, including pro-regenerative astrocytes. 5-bromo-2-deoxyuridine staining will be used to analyze proliferation. GFAP expression will be determined using anti-GFAP antibody conjugated with Alexa Fluor 594. Further, pro-regenerative phenotypic genes Clcf1, Tgm2, and Ptgs2 will be detected via polymerase chain reaction to differentiate from pro-inflammatory astrocytes, a separate category of reactive astrocytes. Anticipated Results: We hypothesize there will be a greater positive correlation between the concentration of FGF-2 or BMP-4 and expression of markers of pro-regenerative phenotype under stiff substrate conditions, compared to softer substrate, thus indicating dependency or synergy between FGF-2 or BMP-4 and extracellular matrix-dependent pathways. Discussion: The correlation between FGF-2 or BMP-4 concentration and the prominence of A2 astrocyte phenotype indicators will be graphed and reported along with a comparison of these correlations between soft and stiff substrate groups. The authors will attempt to conclude whether substrate stiffness significantly effects the activities of FGF-2 or BMP-4. Conclusion: We hope the results of this proposed study will inform the development of neuroregenerative therapies involving astrocytes by indicating the necessity for greater focus on either the application of signalling molecules or modification of ECM.

Heart failure in erythrodermic psoriasis: a retrospective study of 225 patients.

Erythrodermic psoriasis (EP) is a severe form of psoriasis that affects multiple organs, including the cardiovascular system. However, few studies have focused on this condition.This study is aimed to assess the prevalence and factors associated with heart failure in EP patient, and to the measure the serum concentrations of fibroblast growth factor 23 (FGF23), a potential predictor of chronic heart failure. We retrospectively studied patients with EP hospitalized at Peking Union Medical College Hospital between January 2005 to October 2021. The prevalence of heart failure and associated factors was measured. In addition, peripheral blood samples were collected from 17 patients and matched with samples from eight healthy controls, and their serum concentrations of FGF23 were measured by ELISA. We studied 225 patients with EP, with a male: female ratio of 2.7:1 and a mean age of 47.6 ± 16.7 years. Twenty-five (11.1%) participants were diagnosed with heart failure during their hospital stay. The patients with EP and heart failure were older (58.2 years vs. 46.2 years, p = 0.001); had a higher prevalence of a history of coronary heart disease (32.0% vs. 21.5%, p < 0.001), fever (48.0% vs. 23.0%, p = 0.007), infection (56.0% vs. 35.5%, p = 0.046); higher hsCRP concentration (43.2 mg/L vs. 8.2 mg/L, p = 0.005); and higher prevalence of anemia (60.0% vs. 22.0%, p < 0.001), hypoalbuminemia (64.0% vs. 42.0%, p = 0.037), and hyperlipidemia (40.0% vs. 20.0%, p = 0.023) than those without heart failure. The serum FGF23 concentration was significantly higher in patients with EP than controls (493.1 pg/ml vs. 277.8 pg/ml, p = 0.027), and was significantly lower after treatment (395.7 pg/ml vs. 463.1 pg/ml, p = 0.022). Clinicians should be aware of the risk of heart failure in patients with EP, and especially those of advanced age and with a history of coronary heart disease, severe systemic symptoms, high concentrations of inflammatory biomarkers, and poor nutritional status.

#6124 INTERACTIONS BETWEEN FIBROBLAST GROWTH FACTOR 23 AND SYSTEMIC INFLAMMATION IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Abstract Background and Aims In patients with Chronic Kidney Disease (CKD), serum concentration of Fibroblast Growth Factor 23 (FGF23) is inversely correlated with Glomerular Filtration Rate (eGFR), as an adaptive mechanism to counterbalance the alterations of mineral metabolism. Transcription, secretion and cleavage from the intact form (iFGF23) to the c-terminal fraction (cFGF23) are regulated by several mechanisms among which inflammatory mediators seem to play a significant role. We investigated whether there was any correlation between FGF23 and several inflammatory mediators. Method In the present study we evaluated cross sectionally the correlation between FGF23 (iFGF23 and c-FGF23) and some pro-inflammatory (IL-6, TNFα, MCP-1)) and anti-inflammatory (IL-10) cytokines in a cohort of 111 prevalent CKD patients stages III-V not yet on dialysis. We excluded patients with infections or chronic inflammatory diseases in the last 3 months, neoplasia or under immunosuppressive therapy. FGF23 and cytokines were dosed by ELISA. Results Descriptive characteristics of the cohort are reported in Table 1. We found an increase in inflammation as eGFR declines: IL6 (r = -0,315, p&amp;lt;0,001), TNFa (r = -0,202, p = 0,033) and MCP1 (r = -0,278, p = 0,003). Furthermore, the ratio between C-terminal FGF23 to intact FGF23 (c/iFGF23) was directly related to eGFR, even if it did not reach statistical significance (r = 0,127, p = 0,113). The correlations between FGF23 and markers of osteo-mineral metabolism and inflammation are reported in Table 2. We found positive correlations of iFGF23 with: IL-6 (r = 0,465, p&amp;lt;0,001), TNFα (r = 0,241, p = 0,009) and IL-10 (r = 0,198, p = 0,044) Conversely, cFGF23 only correlated with MCP-1 (r = 0,264, p = 0,005). c/iFGF23 resulted inversely correlated with IL-6 (-0,326, p&amp;lt;0,001) and positively with MCP-1 (r = 0,178, p = 0,061). After the adjustment for eGFR, iFGF23 maintained his correlations only with IL-6 (r = 0,370, p &amp;lt; 0,001) and TNFα (r = 0,163, p = 0,044) while c/iFGF23 was negatively correlated with IL-6 (r -0,251, p = 0,008) and positively with MCP-1 (r = 0,204, p = 0,032). Conclusion Our data confirm that in CKD patients, as the renal function declines, there is an important increase of inflammatory cytokines and a tendency to an impaired cleavage of FGF23 from the intact to the c-terminal form. Furthermore, we observed strong correlations of iFGF23 with several inflammatory cytokines (IL-6, TNFα, IL-10) that seem to be independent of eGFR. On the contrary we did not find any correlation of cFGF23 with inflammatory mediators, except for MCP-1. Therefore, we believe that overall our results suggest that inflammatory markers are differently associated with cFGF23 and iFGF23, as if inflammation may independently influence FGF23 turnover (i.e, c/iFGF23 ratio).

Cytokines’ profile of the low-volume uterine lavage in mares with normal postpartum and septic metritis

Even though metritis is one of the most common puerperal diseases in mares, there is a lack of information with regard to the condition. The aim of this study was to evaluate cytokines’ profile in uterine fluid collected with low volume lavage (LVL) from mares with normal postpartum period (PPP) (group 1; N=11) and from mares with septic metritis (group 2; N=12). Septic metritis was defined as the presence of hyperthermia (>38.5°C), depression, an enlarged and an excessive amount of variably echogenic uterine fluid. Mares were treated with oxytetracycline IV q12 h for 5 days, high volume uterine lavage with saline q12 h until necessary. In group 1, LVL was performed 36-48 hours after parturition (T1) and then after 2 days (T2). In group 2, LVL was performed when evidence of septic metritis appeared and then after 2 days of treatment. The samples were centrifuged, the supernatant was removed and stored at -80°C until analysis. Cytokines were measured simultaneously, using Equine Cytokine/Chemokine Panel (Merck-Millipore), based on xMAP technology. Analyzed cytokines were monocyte chemoattractant protein-1 (MCP-1), fibroblast growth factor-2 (FGF-2), granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (INF)-γ, tumor necrosis factor (TNF)-α, interleukins (IL)-1β, 1α, 2, 4, 5, 6, 8, 10, 13, 18. Data are given as median in pg/mL. Differences between groups were analyzed by Mann-Whitney test and between sample times by Wilcoxontest. In group 2, the concentration of most cytokines was larger than in group 1: IL-6 (2256.3 vs 188.2; p<0.01), IL-8 (94.8 vs 72.1; p<0.05), IL-1β (13738.7 vs 16.5; p<0.01), TNF-α (393.2 vs 0.4; p<0.05), INF-γ (224.5 vs 31.6; p<0.05), IL-10 (39.5 vs 7.9; p<0.05). The concentrations of IL-18, IL-13, and FGF-2 did not differ between groups, while IL-1α, 2, 4, 5, MCP-1 and GM-CSF were not detectable. In group 1 there was an increase (p<0.05) in IL-10, IL-5 and IL-18, while in group 2 there was no difference between T1 and T2. All mares with septic metritis recovered well and without any complications. Results suggest that, although an inflammatory response is already present in mares with normal PPP to ensure a proper endometrial regeneration and uterine involution, it is stronger in mares with septic metritis. In both groups, a high percentage (>60%) of neutrophils was detected, suggesting that in physiologic uterine involution, an inflammatory response is required. In agreement with findings from cattle, more neutrophils than monocytes and macrophages are recruited. An intense inflammatory response persists for at least 4 days. It should be noted that metritis was treated without any empirical use of intrauterine antibiotics as suggested by the WHO.

Fibroblast growth factor 2 reduces endoplasmic reticulum stress and apoptosis in in-vitro Non-Alcoholic Fatty Liver Disease model.

Non-Alcoholic fatty liver disease is characterized by the accumulation of excess fat in the liver, chronic inflammation, and cell death, ranging from simple steatosis to fibrosis, and finally leads to cirrhosis and hepatocellular carcinoma. The effect of Fibroblast growth factor 2 on apoptosis and ER stress inhibition has been investigated in many studies. In this study, we aimed to investigate the effect of FGF2 on the NAFLD in-vitro model in the HepG2 cell line. The in-vitro NAFLD model was first induced on the HepG2 cell line using oleic acid and palmitic acid for 24h and evaluated by ORO staining and Real-time PCR. The cell line was then treated with various concentrations of fibroblast growth factor 2 for 24h, total RNA was extracted and cDNA was consequently synthesized. Real-time PCR and flow cytometry was applied to evaluate gene expression and apoptosis rate, respectively. It was shown that fibroblast growth factor 2 ameliorated apoptosis in the NAFLD in-vitro model by reducing the expression of genes involved in the intrinsic apoptosis pathway, including caspase 3 and 9. Moreover, endoplasmic reticulum stress was decreased following upregulating the protective ER-stress genes, including SOD1 and PPARα. FGF2 significantly reduced ER stress and intrinsic apoptosis pathway. Our data suggest that FGF2 treatment could be a potential therapeutic strategy for NAFLD.

GPR30-mediated non-classic estrogen pathway in mast cells participates in endometriosis pain via the production of FGF2.

Pain is one of the main clinical symptoms of endometriosis, but its underlying mechanism is still not clear. Recent studies have shown that the secretory mediators of mast cells activated by estrogen are involved in the pathogenesis of endometriosis-related pain, but how estrogen-induced mast cell mediators are involved in endometriosis-related pain remains unclear. Here, mast cells were found to be increased in the ovarian endometriotic lesions of patients. They were also closely located closely to the nerve fibers in the ovarian endometriotic lesions from of patients with pain symptoms. Moreover, fibroblast growth factor 2 (FGF2)-positive mast cells were upregulated in endometriotic lesions. The concentration of FGF2 in ascites and the protein level of fibroblast growth factor receptor 1 (FGFR1) were higher in patients with endometriosis than in those without endometriosis, and they were correlated with pain symptoms. In vitro, estrogen could promote the secretion of FGF2 through G-protein-coupled estrogen receptor 30 (GPR30) via the MEK/ERK pathway in rodent mast cells. Estrogen-stimulated mast cells enhanced the concentration of FGF2 in endometriotic lesions and aggravated endometriosis-related pain in vivo. Targeted inhibition of the FGF2 receptor significantly restrained the neurite outgrowth and calcium influx in dorsal root ganglion (DRG) cells. Administration of FGFR1 inhibitor remarkably elevated the mechanical pain threshold (MPT) and prolonged the heat source latency (HSL) in a rat model of endometriosis. These results suggested that the up-regulated production of FGF2 by mast cells through non-classic estrogen receptor GPR30 plays a vital role in the pathogenesis of endometriosis-related pain.

FORMULATION OF MESENCHYMAL STEM CELL SECRETOME AS ANTIAGING CREAM

Objective: Skin aging occurs not only due to age but is influenced by various environmental factors such as lifestyle, pollution, and excessive exposure to UV rays. Secretomes can act as antiaging agents that stimulate collagen biosynthesis naturally in the skin. This study aims to create a cream containing 5% secretome with essential oil, dermatological examination, and Fibroblast Growth Factor (FGF) checking.&#x0D; Methods: Antiaging efficacy testing involves examination by an expert dermatologist for assessment before and after using the cream. The antiaging impact test criteria include moisture, elasticity, and collagen values. Consequently, the cream shows an antiaging activity.&#x0D; Results: The antiaging efficacy test revealed increased moisture from 24.375±11.97 to 25.125±7.1; the skin elasticity also increased from 40.375±8.39 to 48.5±9.09 and the collagen value increased from 48.25±13.54 to 56.5±8.63. The result shows that the cream contains a 61.143 pg/ml concentration of FGF using an ELISA kit.&#x0D; Conclusion: The formula for cream preparations containing 5% secretome with essential oil meets the requirements of cosmetics through several evaluations of the trial. It has an antiaging effect, proven through several tests.

Homocysteine-induced endoplasmic reticulum stress activates FGF21 and is associated with browning and atrophy of white adipose tissue in Bhmt knockout mice

Betaine-homocysteine methyltransferase (BHMT) catalyzes the transfer of methyl groups from betaine to homocysteine (Hcy), producing methionine and dimethylglycine. In this work, we characterize Bhmt wild type (Bhmt-WT) and knockout (Bhmt-KO) mice that were fully backcrossed to a C57Bl6/J background. Consistent with our previous findings, Bhmt-KO mice had decreased body weight, fat mass, and adipose tissue weight compared to WT. Histological analyses and gene expression profiling indicate that adipose browning was activated in KO mice and contributed to the adipose atrophy observed. BHMT is not expressed in adipose tissue but is abundant in liver; thus, a signal must originate from the liver that modulates adipose tissue. We found that, in Bhmt-KO mice, homocysteine-induced endoplasmic reticulum (ER) stress is associated with activation of the hepatic transcription factor cyclic AMP response element binding protein (CREBH), and an increase in hepatic and plasma concentrations of fibroblast growth factor 21 (FGF21), which is known to induce adipose browning. Our data indicate that the deletion of a single gene in one-carbon metabolism modifies adipose biology and energy metabolism. Future studies could focus on identifying if functional polymorphisms in BHMT result in a similar adipose atrophy phenotype.

An Array SPRi Biosensor for Simultaneous VEGF-A and FGF-2 Determination in Biological Samples

A new method was developed for the simultaneous determination of vascular endothelial growth factor (VEGF-A) and fibroblast growth factor-2 (FGF-2) in blood serum, using biosensors with array Surface Plasmon Resonance imaging (SPRi) detection. It can be applied as a single method for simultaneous VEGF-A and FGF-2 determination or as two separate methods for testing only one selected protein in each case. Validation was carried out for each method. Limit of detection (LOD) and limit of quantification (LOQ) values were determined and were found not to differ significantly from the parameters obtained in comparisons with commercial enzyme-linked immunosorbent assay (ELISA) tests. Tests were carried out to check the robustness of the method. The results indicate a lack of robustness of the analytical method to elevated temperature and pH values other than those recommended by the manufacturers of the reagents (recommended pH = 7.40). The values of recoveries were determined and confirmed the reliability of the results obtained with the use of the newly developed method. The selectivity studies showed no negative influence of other proteins present in the matrix of the tested samples on the results of the VEGF-A and FGF-2 concentration measurements. The developed method is also characterized by high reproducibility of the results obtained and agreement with the VEGF-A and FGF-2 concentration values obtained with commercial ELISA tests. The proposed method offers fast, reproducible, and accurate simultaneous quantification of VEGF-A and FGF-2 in human body fluids. Only 4 µL of test sample are required for simultaneous analysis. The total time for simultaneous analysis of both biomarkers does not exceed 20 min. The developed analytical method is superior to ELISA in terms of analysis time and sample volume for analysis, and it offers lower LOD and LOQ values and allows for the simultaneous analysis of two biomarkers. There is also no need to collect a large number of samples. Standard ELISAs usually have 96 reaction wells. The proposed biosensor can be used to analyse only one sample, without the need to waste reagents on unused reaction sites. In addition, it is possible to regenerate the biosensor and reuse it.

Growth pattern in children with X-linked hypophosphatemia treated with burosumab and growth hormone

BackgroundX-linked hypophosphatemia (XLH) is characterized by increased serum concentrations of fibroblast growth factor 23 (FGF23), hypophosphatemia and insufficient endogenous synthesis of calcitriol. Beside rickets, odonto- and osteomalacia, disproportionate short stature is seen in most affected individuals. Vitamin D analogs and phosphate supplements, i.e., conventional therapy, can improve growth especially when started early in life. Recombinant human growth hormone (rhGH) therapy in XLH children with short stature has positive effects, although few reports are available. Newly available treatment (burosumab) targeting increased FGF23 signaling leads to minimal improvement of growth in XLH children. So far, we lack data on the growth of XLH children treated with concomitant rhGH and burosumab therapies.ResultsThirty-six patients received burosumab for at least 1 year after switching from conventional therapy. Of these, 23 received burosumab alone, while the others continued rhGH therapy after switching to burosumab. Children treated with burosumab alone showed a minimal change in height SDS after 1 year (mean ± SD 0.0 ± 0.3 prepubertal vs. 0.1 ± 0.3 pubertal participants). In contrast, rhGH clearly improved height during the first year of treatment before initiating burosumab (mean ± SD of height gain 1.0 ± 0.4); patients continued to gain height during the year of combined burosumab and rhGH therapies (mean ± SD height gain 0.2 ± 0.1). As expected, phosphate serum levels normalized upon burosumab therapy. No change in serum calcium levels, urinary calcium excretion, or 25-OHD levels was seen, though 1,25-(OH)2D increased dramatically under burosumab therapy.ConclusionTo our knowledge, this is the first study on growth under concomitant rhGH and burosumab treatments. We did not observe any safety issue in this cohort of patients which is one of the largest in Europe. Our data suggest that continuing treatment with rhGH after switching from conventional therapy to burosumab, if the height prognosis is compromised, might be beneficial for the final height.

The relationship between the level of vitamin D, leptin and FGF23 in girls and young women with polycystic ovary syndrome.

Polycystic ovary syndrome is an endocrinopathy that mainly affects adolescent girls and young women of childbearing age. In girls, the presence of clinical and biochemical symptoms of hyperandrogenism should be particularly considered. The role of vitamin D deficiency in insulin resistance, inflammation, dyslipidemia, and obesity, i.e. in diseases associated with PCOS, has been investigated, which may suggest its involvement in the pathophysiology of the syndrome. Leptin has been shown to stimulate the formation of FGF23 in bones. There is a relationship between the incidence of dyslipidemia, adipose tissue mass and the concentration of fibroblast growth factor 23. The main aim of the presented research project is to assess the concentration of vitamin D, calcium, and selected hormones as well as the concentration of adipokines (leptin) in girls diagnosed with polycystic ovary syndrome.Materials and methodsThe study included a population of 85 girls and young women aged 14 to 22 years. The study group included 37 girls who were diagnosed with polycystic ovary syndrome according to the modified Rotterdam’s criteria. The control group consisted of 48 completely healthy girls. In the first stage of the study participants were required to answer background questions. Next, anthropometric measurements were performed. The laboratory tests assessed: leptin, FGF23, FSH, SHGB, total testosterone, DHEA-S, 25-OH-D3, PTH, calcium, androstadiene, AMH, glucose, insulin.ResultsThe vitamin D level in the group with polycystic ovary syndrome was lower than in the control group, but there was no statistically significant difference. The level of anti-Müllerian hormone was significantly higher in the group of girls diagnosed with PCOS compared to the control group. Statistically significant differences between both groups were also noted in the HOMA-IR value. The concentration of calcium, parathyroid hormone, FGF23 and leptin in the study and control groups showed no statistically significant difference.ConclusionsIn the studied group of girls with PCOS, no correlation between the level of vitamin D and selected parameters such as: AMH leptin, HOMA-IR and FGF23 was confirmed. On this basis, it can be assumed that additional vitamin D supplementation would not reduce the symptoms of polycystic ovary syndrome.

FGF 10 Inhibited Spinal Microglial Activation in Neuropathic Pain via PPAR-γ/NF-κB Signaling

Overactivated microglia in the spinal cord leads to neuropathic pain sensitivity. The FGF 10, a Fibroblast Growth Factor (FGFs) that is prevalent in neurons, has been demonstrated to suppress microglial polarization. The objective of this study was to investigate the role of FGF 10 in neuropathic pain and the underlying regulatory mechanisms. Immunofluorescence staining and western blot detection revealed that FGF 10 expression was upregulated in the ipsilateral spinal dorsal horn of Spared Nerve Injury (SNI) rat models and was mainly detected in neurons and microglia. To test the anti-microgliosis actions of FGF 10, SNI rats were intrathecally administered with different concentrations of recombinant FGF 10. Behavioral tests and immunostaining results showed that FGF 10 relieved hyperalgesia in SNI rats and inhibited microglial activity in the ipsilateral spinal dorsal horn in a dose-dependent manner. Besides, BV2 cells were cultured and treated with LPS to activate microglia to explore the underlying mechanisms of FGF 10-induced analgesic effects in vitro. As a result, FGF 10 administration suppressed the LPS-induced microglial augmentation in a dose-dependent manner, followed by increased PPAR-γ and decreased NFκB phosphorylation (p-NFκB) levels. Moreover, PPAR-γ agonist (pioglitazone) and antagonist (GW9662) were administrated into spinal cords of SNI rats, revealing that pioglitazone had similar anti-nociceptive and anti-microglial effects to FGF 10. Conversely, GW9662 reversed all beneficial effects of FGF 10 on SNI rats. In addition, phosphorylated levels of NFκB were reduced by pioglitazone or FGF 10 treatment but raised by GW9662 administration in FGF 10-treated SNI rats. Our findings show that FGF 10 has analgesic effects in rats after peripheral nerve injury and justify the role of PPAR-γ/NFκB signaling in FGF 10-regulated anti-microgliosis.

The initial delay to mitotic activity in primary cultures of equine satellite cells is reduced by combinations of growth factors.

Satellite cell (SC) activation is defined as the time frame during which the stem cell becomes poised to reenter G1 of the cell cycle. The growth factors and events leading to full mitotic activation in equine SCs remain largely unknown. Insulin-like growth factor I (IGF-I), hepatocyte growth factor (HGF), and fibroblast growth factor 2 (FGF2) are sequentially transcribed during the muscle repair and recovery period following strenuous exercise in adult horses. Expression of IGF-I occurs within 24 h of the postexercise recovery period suggesting it may affect early SC actions. As a first step, gluteus medius muscle cryosections from adult horses (n = 9) were examined for the presence of central nuclei (CN), a marker of SC addition to the fiber. Results demonstrate few CN fibers prior to exercise with a 3-fold increase (P = 0.05) 24 h postexercise. Cultures of SC (n = 4 isolates) were treated with 100 ng/mL IGF-I for varying times prior to measurement of myogenic events. Results demonstrate that IGF-I does not affect the initial lag period, proliferation, or subsequent differentiation of equine SC in vitro (P > 0.05). However, media containing a combination of IGF-I and 10 ng/mL FGF2 and 25 ng/mL HGF hastens (P < 0.05) the time to S-phase entry in fresh isolates of SCs. Media supplementation with optimal concentrations of FGF2, HGF, or a combination of HGF and FGF2 suppresses (P < 0.05) the percentage of myogenin immunopositive SCs to levels below that found in control- or IGF-I-treated SCs. These results provide new insight into the combinatorial roles growth factors play during equine SC myogenesis.

Changes in Serum Intact Fibroblast Growth Factor 23 Concentrations From Midlife to Late Life and Their Predictors in the Community: The ARIC Study.

ObjectiveTo investigate longitudinal changes in the blood concentration of fibroblast growth factor 23 (FGF23) from midlife to late life and their major predictors in the general population.Patients and MethodsIn 14,444 participants of the Atherosclerosis Risk in Communities Study, we analyzed the association of 31,095 measurements of serum intact FGF23 with age using data from 3 visits (visit 2 [N=13,460; mean age, 57 years]; visit 3 [N=12,323; mean age, 60 years]; and visit 5 [N=6122; mean age, 76 years]) and a linear mixed-effects model. Among 5804 participants who had FGF23 measurements at both visits 3 and 5, we explored predictors of FGF23 change from midlife to late life using linear regression models. Prespecified risk factors were estimated glomerular filtration rate, body mass index, ever smoking, ever drinker, diabetes, hypertension, history of cardiovascular disease, total cholesterol, and high-density lipoprotein cholesterol.ResultsMedian FGF23 concentrations were 41.9 pg/mL (interquartile interval [IQI], 33.9 to 51.8 pg/mL) at visit 2, 38.3 pg/mL (IQI, 30.6 to 48.3 pg/mL) at visit 3, and 55.0 pg/mL (IQI, 44.4 to 70.3 pg/mL) at visit 5. A linear mixed-effects model showed that the association of FGF23 with age was nonlinear, with a slight decline or no change in age 45-60 years and a monotonic increase in age greater than or equal to 65 years (FGF23, +10 to 15 pg/mL per 10 years of age). In a multivariable linear regression model, significantly greater increases in FGF23 were noted, with midlife estimated glomerular filtration rate less than 60 mL/min per 1.73 m2 vs more than or equal to 60 mL/min per 1.73 m2 (ΔFGF23, +4.4 pg/mL [95% CI, 0.9 to 8.0]), diabetes vs no diabetes (ΔFGF23, +6.2 pg/mL [95% CI, 4.1 to 8.3]), and hypertension vs no hypertension (ΔFGF23, +4.1 pg/mL [95% CI, 2.7 to 5.4]).ConclusionFGF23 did not show any major changes in midlife but increased linearly in late life. Reduced kidney function, diabetes, and hypertension were robustly associated with a greater increase in FGF23. Further investigations are needed to understand the potential mechanisms linking these conditions to an increase in FGF23 concentrations.

Fibroblast growth factor-2 promotes in vitro activation of cat primordial follicles.

This study evaluated the effect of fibroblast growth factor-2 (FGF-2) on the morphology, primordial follicle activation and growth after in vitro culture of domestic cat ovarian tissue. Ovaries (n = 12) from prepubertal domestic cats were collected and fragmented. One fragment was fixed for histological analysis (fresh control). The remaining fragments were incubated in control medium alone or with 10, 50 or 100 ng/ml FGF-2 for 7 days. After in vitro culture, the following endpoints were analyzed: morphology, activation by counting primordial and developing follicles, and growth (follicle and oocyte diameters). Treatment with 100 ng/ml FGF-2 maintained (P > 0.05) the percentage of normal follicles similar to fresh control. Follicle survival was greater (P < 0.05) after culture in 100 ng/ml FGF-2 than in 50 ng/ml FGF-2. The percentage of primordial follicles decreased (P < 0.05) and the percentage of developing follicles increased (P < 0.05) in all treatments compared with fresh tissue. The proportion of developing follicles increased (P < 0.05) in tissues incubated with 100 ng/ml FGF-2 compared with control medium and other FGF-2 concentrations. Furthermore, culture in 10 or 100 ng/ml FGF-2 resulted in increased (P < 0.05) follicle and oocyte diameters compared with fresh tissues and MEM+. In conclusion, FGF-2 at 100 ng/ml maintains follicle survival and promotes the in vitro activation and growth of cat primordial follicles.

Contribution of phosphate and FGF23 to CKD progression.

Progressive forms of chronic kidney disease (CKD) exhibit kidney inflammation and fibrosis that drive continued nephron loss; however, factors responsible for the development of these common pathologic features remain poorly defined. Recent investigations suggest pathways involved in maintaining urinary phosphate excretion in CKD may be contributing to kidney function decline. This review provides an update on recent evidence linking altered phosphate homeostasis to CKD progression. High dietary phosphate intake and increased serum concentrations of fibroblast growth factor 23 (FGF23) both increase urinary phosphate excretion and are associated with increased risk of kidney function decline. Recent investigations have discovered high concentrations of tubular phosphate promote phosphate-based nanocrystal formation that drives tubular injury, cyst formation, and fibrosis. Studies presented in this review highlight important scientific discoveries that have molded our current understanding of the contribution of altered phosphate homeostasis to CKD progression. The collective observations from these investigations implicate phosphaturia, and the resulting formation of phosphate-based crystals in tubular fluid, as unique risk factors for kidney function decline. Developing a better understanding of the relationship between tubular phosphate handling and kidney pathology could result in innovative strategies for improving kidney outcomes in patients with CKD.