Association of brown adipose tissue activity with circulating sex hormones and fibroblast growth factor 21 in the follicular and luteal phases in young women.

BACKGROUND: Thermogenesis is influenced by fluctuations in sex hormones during the menstrual cycle in premenopausal women. The thermogenic activity and mass of brown adipose tissue (BAT) are regulated by endocrine factors, including sex hormones and fibroblast growth factor 21 (FGF21). However, the relationship between human BAT and these endocrine fluctuations within individuals remains to be elucidated. This study aimed to assess variations in BAT activity between the luteal and follicular phases and identify correlations with circulating levels of sex hormones and FGF21. METHODS: Healthy young women were enrolled in an observational study. Measurement of BAT activity and blood analyses were performed in both the follicular and luteal phases. BAT activity was analyzed using thermography with 2-h cold exposure. Plasma 17ß-estradiol, progesterone, and FGF21 levels were determined by enzyme-linked immunosorbent assay. A comparative analysis within individuals was conducted in 13 women to compare the follicular and luteal phases. Furthermore, sensitivity analysis was carried out in 21 women during the follicular phase only. RESULTS: Plasma 17ß-estradiol and progesterone levels were significantly higher in the luteal phase, whereas plasma FGF21 level was significantly higher in the follicular phase. Comparison analysis found no significant differences in cold-induced BAT activity between the follicular and luteal phases in young women. Correlation analysis in both comparison and sensitivity analyses found that plasma 17ß-estradiol and progesterone levels were not associated with BAT activity, whereas plasma FGF21 levels were significantly and positively correlated with BAT activity only in the follicular phase. In addition, plasma 17ß-estradiol levels in the follicular phase were significantly and positively associated with plasma FGF21 levels in both the comparison and sensitivity analyses. CONCLUSIONS: The thermogenic activity of BAT during cold exposure was comparable between the follicular and luteal phases in young women. Higher BAT activity was associated with elevated levels of plasma FGF21 only in the follicular phase, which is related to increased plasma 17ß-estradiol levels.

Diosmin and Hesperidin Have a Protective Effect in Diabetic Neuropathy via the FGF21 and Galectin-3 Pathway.

Background and Objectives: This study aimed to investigate the protective effect of diosmin and hesperidin in diabetic neuropathy using a rat model, focusing on their impact on nerve regeneration through the fibroblast growth factor 21 (FGF21) and galectin-3 (gal3) pathway. Materials and Methods: Forty adult male Wistar rats were used in this study. Diabetes was induced using streptozotocin (STZ), and the rats were divided into control, diabetes and saline-treated, diabetes and diosmin + hesperidin (150 mg/kg) treated, and diabetes and diosmin + hesperidin (300 mg/kg) treated groups. Electromyography (EMG) and inclined plane testing were performed to assess nerve function and motor performance. Sciatic nerve sections were examined histopathologically. Plasma levels of FGF21, galectin-3, and malondialdehyde (MDA) were measured as markers of oxidative stress and inflammation. Results: Diabetic rats treated with saline displayed reduced nerve conduction parameters and impaired motor performance compared to controls. Treatment with diosmin and hesperidin significantly improved compound muscle action potential (CMAP) amplitude, distal latency, and motor performance in a dose-dependent manner. Histopathological examination revealed decreased perineural thickness in treated groups. Additionally, treatment with diosmin and hesperidin resulted in increased plasma FGF21 levels and reduced plasma levels of galectin-3 and MDA, indicating decreased oxidative stress and inflammation. Conclusions: Diosmin and hesperidin exhibited protective effects in diabetic neuropathy by promoting nerve regeneration, enhancing nerve conduction, and improving motor performance. These effects were associated with modulation of the FGF21 and galectin-3 pathway. These findings suggest that diosmin and hesperidin may hold potential as adjunctive therapies for diabetic neuropathy.

Short and long-term effects of kidney donation on mineral and bone metabolism.

BACKGROUND: Living kidney donors (LKD) experience an abrupt decline in glomerular filtration rate (GFR) resulting in abnormalities of mineral and bone metabolism (MBD), and this may have implications for skeletal health. We prospectively studied acute and long term MBD adaptation of LKD from two kidney transplant centers (São Paulo, Brazil and Miami, USA). METHODS: Renal function and MBD parameters longitudinally after kidney donation (baseline - D0, day 1, 14, 180 and 360 post-operatively) were measured in 74 patients (40 y, 73% female, 54% Brazilian). A subset of 20 donors from Brazil were reassessed after 10 years of nephrectomy. RESULTS: At baseline, Brazilian donors presented lower intact FGF23 (20.8 vs. 80.1 pg/mL, P < 0.01) and higher PTH (47.4 vs. 40.1, P = 0.04) than their US counterparts. GFR decreased to 63% of its baseline levels just after donation but improved 10% during the first year. PTH levels increased on D1, returning to baseline levels on D14, while FGF23 remained higher than baseline over the first year. LKD had a significant reduction of serum phosphate on D1, which returned to baseline levels on D180. A higher fractional excretion of phosphate (FEP) was noted since D14. After 10 years of donation, 20 LKD presented a sustained reduction in GFR (74.8 ± 14mL/min). There was a return to baseline in serum FGF23 [21.8 (18-30) pg/mL] and FEP, accompanied by an increase in serum calcium. PTH remained elevated (57.9 ± 18 pg/mL), whereas serum calcitriol and Klotho were lower than before the donation. CONCLUSIONS: The abrupt decline in kidney mass is associated with an increase in PTH and FGF23 that is not explained by phosphate retention. In a long-term evaluation, LKD showed a sustained drop in GFR, with lower serum calcitriol and Klotho, and higher PTH. The effects of these changes should be investigated in further studies.

Exploring causal correlations between inflammatory cytokines and coronary heart disease: A Mendelian randomization study.

Coronary heart disease (CHD) is a global health concern, with inflammation significantly contributing to its pathogenesis. It is crucial to understand the relationship between inflammatory cytokines and CHD. This study investigates the causal correlations between circulating inflammatory cytokines and CHD using Mendelian randomization (MR), assessing both causative and resultant roles of these cytokines in CHD. In this bidirectional MR analysis, we used genetic data from a genome-wide association study (GWAS) of 60,801 CHD cases and 123,504 controls of European ancestry. We derived inflammatory cytokine data from a GWAS summary of 14,824 participants. The primary analytical approach was the inverse variance-weighted (IVW) method, supported by MR-Egger, weighted median, and weighted mode analyses. Heterogeneity was assessed using the Cochrane Q test, and horizontal pleiotropy was evaluated through the MR-Egger intercept and the MR-PRESSO global test, ensuring robustness against potential pleiotropic bias. This study pinpointed several cytokines as key upstream influencers on the risk of CHD, including eotaxin (CCL11) (odds ratio [OR]: 1.10, 95% confidence interval [CI]: 1.03-1.18, P = .003), C-C motif chemokine ligand 20 (CCL20) (OR: 1.15, 95% CI: 1.05-1.25, P = .002), macrophage colony-stimulating factor 1 (CSF1) (OR: 1.09, 95% CI: 1.01-1.17, P = .020), Fibroblast growth factor 21 (FGF21) (OR: 1.14, 95% CI: 1.01-1.29, P = .038), Fms-related tyrosine kinase 3 ligand (FLT3LG) (OR: 1.26, 95% CI: 1.09-1.44, P = .001), neurotrophin-3 (NT-3) (OR: 1.12, 95% CI: 1.01-1.24, P = .026), and leukemia inhibitory factor (LIF) (OR: 0.89, 95% CI: 0.80-0.99, P = .029). Conversely, T-cell surface glycoprotein CD5 (CD5) (beta: -0.15, 95% CI: -0.29 to -0.01, P = .042) were identified as downstream factors impacted by CHD. No evidence of heterogeneity or horizontal pleiotropy was detected across all results, and a leave-one-out analysis substantiated the robustness of these findings. These findings suggest that CCL11, CCL20, CSF1, FGF21, FLT3LG, NT-3, and LIF may play a crucial role in the pathogenesis of CHD. Additionally, CHD may impact the expression of CD5. Additional research is needed to explore the potential of these biomarkers in the prevention and treatment of CHD.

Clinical significance of serum FGF21 levels in diagnosing nonalcoholic fatty liver disease early.

The endogenous FGF21 level is a potential target for diagnosing NAFLD. This study aimed to assess the clinical utility of FGF21 in diagnosing NAFLD and provide new ideas for predicting and preventing NAFLD. A total of 193 patients diagnosed with NAFLD based on diagnostic criteria and 64 healthy individuals were included in the NAFLD and non-NAFLD groups, respectively. Data on the participant names, sex, age, height, weight, blood pressure, serum FGF21 levels, liver function enzyme (AST, ALT, ALP, and GGT) levels, lipid profile (TC, TG, HDL-C, and LDL-C) indicators, and blood glucose levels were collected. The data were statistically analyzed to assess the correlations between serum FGF21 levels and related biochemical markers in NAFLD patients. The areas under the receiver operating characteristic curves (AUCs) of serum FGF21, lipids (TG + TC + HDL + LDL), and FGF21 combined with lipids for the diagnosis of NAFLD were compared. Compared with the non-NAFLD group, the NAFLD group presented significantly higher levels of FGF21. Serum FGF21 levels in the NAFLD group were positively correlated with the TG, TC, and LDL-C levels (P < 0.05). The area under the receiver operating characteristic curve (AUC) of serum FGF21 for the diagnosis of NAFLD was 0.832 (95% CI: 0.77-0.886, P < 0.001). The AUC of FGF21 combined with lipids (TG + TC + HDL + LDL) for the diagnosis of NAFLD was 0.910 (95% CI: 0.874-0.946, P < 0.001). There is a close association between elevated FGF21 levels and the development of NAFLD. The progression of NAFLD is complex and varied, and its pathogenesis is unclear. Early detection, prevention, and intervention may help slow NAFLD development or even reverse the disease. In this study, we found that the FGF21 level could be used as an auxiliary biological indicator for predicting NAFLD, and the role of FGF21 in the progression of NAFLD deserves to be investigated in the future.

Carotid intima-media thickness, fibroblast growth factor 23, and mineral bone disorder in children with chronic kidney disease.

BACKGROUND: Carotid intima-media thickness (cIMT) is a measure of atherosclerotic vascular disease and a surrogate biomarker for cardiovascular risk in patients with chronic kidney disease (CKD). Mineral and bone disorders (MBD) are complications of CKD, contributing to vascular calcification and accelerated atherosclerosis. Increased fibroblast growth factor 23 (FGF23)-the earliest detectable serum abnormality associated with CKD-MBD-has been linked with cardiovascular disease in patients with CKD. This study aimed to identify factors and analyze the relationship associated with high cIMT, high FGF23, and poor MBD control in children with CKD. METHODS: A cross-sectional study was conducted in Yogyakarta, Indonesia recruiting children with CKD. The correlations and factors between cIMT, FGF23, and MBD were explored. RESULTS: We recruited 42 children aged 2-18 years old with CKD stages 2 to 5D. There were no significant correlations between cIMT and factors including advanced CKD, use of dialysis, body mass index, hypertension, anemia, MBD, FGF23 levels, and left ventricular mass index (LVMI). Patients with advanced CKD had poorly controlled anemia, hypertension, and higher LVMI. In multivariate analysis, CKD stages, hypertension stages, the presence of MBD, and LVMI were associated with FGF23 levels (p < 0.05). CONCLUSIONS: FGF23 levels increased with CKD progression, and MBD was more prevalent in advanced kidney disease. Elevated FGF23 is potentially associated with increased MBD prevalence in late-stage CKD. A larger study is needed to confirm the factors affecting cIMT in children with CKD.

Relationship of fibroblast growth factor 21, Klotho, and diabetic retinopathy: a meta-analysis.

Background: Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus. Research has identified a close relationship between fibroblast growth factor 21 (FGF21) and DR. FGF21 is a member of the FGF subfamily, which is activated by the Klotho coenzyme involved in the occurrence of DR. However, the association between FGF21, Klotho, and DR remains controversial. Aim: To assess FGF21 and Klotho levels in patients with DR. Methods: A literature search of the Web of Science, Wiley Online Library, PubMed, China National Knowledge Infrastructure and Wanfang databases was performed. The title or abstract search terms "diabetic retinopathy" and "DR" were used in combination with "fibroblast growth factor 21", "FGF21", and "Klotho". Meta-analysis results are presented as standardized mean difference (SMD) with corresponding 95% confidence interval (CI). Results: Fifteen studies were included in this meta-analysis. FGF21 levels in patients with DR were significantly higher than in non-DR patients with diabetes (SMD: 2.12, 95% CI [1.40, 2.84]). Klotho levels in patients with DR were significantly lower than in non-DR patients with diabetes (SMD: -0.63, 95% CI [-1.22, - 0.04]). Conclusions: This systematic review is the first to evaluate the relationship between FGF21, Klotho levels, and DR. FGF21 levels were significantly higher in patients with DR. Fully elucidating the role of FGF21 will significantly contribute to the treatment of DR.

A Randomized Controlled Trial to Determine the Impact of Resistance Training versus Aerobic Training on the Management of FGF-21 and Related Physiological Variables in Obese Men with Type 2 Diabetes Mellitus.

Fibroblast growth factor 21 (FGF-21) has been suggested as a potential therapeutic target for insulin resistance in health-related metabolic disorders such as type 2 diabetes. Despite the metabolic effects of resistance (RT) and aerobic training (AT) on diabetes symptoms, uncertainty exists regarding the superiority of effects manifested through these training approaches on FGF-21 and biochemical and physiological variables associated with metabolic disorders in men diagnosed with type 2 diabetes. This study aimed to investigate the impact of a 12-week RT and AT on FGF-21 levels and symptoms associated with metabolic disorders in male individuals diagnosed with type 2 diabetes. Thirty-six sedentary obese diabetic men (40 to 45 years old) were matched based on the level of FGF-1. They and were randomly divided into two training groups (RT, n = 12 and AT, n = 12) performing three days per week of moderate-intensity RT or AT for 12 weeks and an inactive control group (n = 12). Both training interventions significantly improved FGF-21, glucose metabolism, lipid profile, hormonal changes, strength, and aerobic capacity. Subgroup analysis revealed that RT had greater adaptive responses (p < 0.01) in fasting blood sugar (ES = -0.52), HOMA-IR (ES = -0.87), testosterone (ES = 0.52), cortisol (ES = -0.82), FGF-21 (ES = 0.61), and maximal strength (ES = 1.19) compared to AT. Conversely, AT showed greater changes (p < 0.01) in cholesterol (ES = -0.28), triglyceride (ES = -0.64), HDL (ES = 0.46), LDL (ES = -0.73), and aerobic capacity (ES = 1.18) compared to RT. Overall, both RT and AT interventions yielded significant moderate to large ES in FGF-21 levels and enhanced the management of biochemical variables. RT is an effective method for controlling FGF-21 levels and glucose balance, as well as for inducing hormonal changes. On the other hand, AT is more suitable for improving lipid profiles in overweight men with type 2 diabetes mellitus.

Blood concentrations of α-Klotho and FGF-23 exhibit no correlation with bone mineral density in elderly individuals.

OBJECTIVE: To investigating the relationship between α-Klotho and FGF-23 with bone biochemical markers and bone density findings in extremely aged individuals. METHODS: A total of 55 individuals with a mean age of 85.6 years were subjected to clinical, biochemical, and bone mineral density analyses and the enzyme-linked immunosorbent assay-based detection of α-Klotho and FGF-23. The mean, standard deviation, median, and interquartile ranges of the sample values were determined, and Spearman's test for association assessments was used for statistical analysis. RESULTS: The study participants expressed median FGF-23 and α-Klotho levels of 69.81 RU/mL (51.43 RU/mL) and 733.43 pg/mL (360.83 pg/mL), respectively. The majority of the participants possessed osteopenia (54.5%) and a vitamin D deficiency (57%). The 25-hydroxyvitamin D concentrations ranged between 7.1 and 47.5ng/mL, with a median of 18.1ng/mL. CONCLUSION: No substantial associations were discovered between α-Klotho and FGF-23 levels and bone density in the study participants.

Mediating role of inflammatory biomarkers in the causal effect of body composition on glycaemic traits and type 2 diabetes.

OBJECTIVE: The aim was to investigate the mediating role of inflammatory biomarkers in the causal effect of body composition on glycaemic traits and type 2 diabetes. METHODS: A retrospective observational study and a Mendelian randomization (MR) study were used. Observational analyses were performed using data from 4717 Chinese children and adolescents aged 6-18 years who underwent dual-energy X-ray absorptiometry for body composition. MR analyses were based on summary statistics from UK Biobank, deCODE2021, Meta-Analysis of Glucose and Insulin-Related Traits Consortium (MAGIC) and other large consortiums. Inflammatory biomarkers included leptin, adiponectin, osteocalcin, fibroblast growth factor 23 (FGF23) and parathyroid hormone (PTH). RESULTS: In a retrospective observational study, increased fat mass had a positive effect on homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of pancreatic beta cell function (HOMA-ß) through FGF23, whereas fat-free mass produced the opposite effects. PTH and osteocalcin played significant roles in the association of fat mass and fat-free mass with fasting glucose, fasting insulin and HOMA-IR (all p < 0.05). Mediation MR results indicated that childhood body mass index affected glycaemic traits through leptin and adiponectin. There existed a causal effect of fat-free mass on type 2 diabetes via FGF23 (indirect effect: OR [odds ratio]: 1.14 [95% CI, confidence interval: 1.01-1.28]) and adiponectin (OR: 0.85 [95% CI: 0.77-0.93]). Leptin mediated the causal association of fat mass (indirect effect: ß: -0.05 [95% CI: -0.07, -0.02]) and fat-free mass (ß: 0.03 [95% CI: 0.01, 0.04]) with fasting glucose. CONCLUSIONS: Our findings suggest that different body compositions have differential influences on glycaemic traits and type 2 diabetes through distinct inflammatory biomarkers. The findings may be helpful in tailoring management of body composition based on inflammatory biomarkers with different glycaemic statuses.

Potential Diagnostic Role of Serum Fibroblast Growth Factor-19 in Hepatocellular Carcinoma.

INTRODUCTION: A highly accurate diagnostic method is crucial to reduce mortality and increase hepatocellular carcinoma (HCC) survival. Current biomarkers have limited accuracy, and novel ones are needed. Fibroblast growth factor-19 (FGF-19) is overexpressed in HCC. This study aimed to assess FGF-19 as a potential novel diagnostic biomarker for HCC. METHODS: This case-control study involved 114 individuals divided into three equal groups: HCC (n=38), Cirrhosis (n=38), and Control (n=38). HCC biomarkers included alpha-fetoprotein (AFP), Des-γ-carboxy prothrombin (DCP), and FGF-19. RESULTS: The three markers, FGF-19, DCP, and AFP, were significantly different between the three groups, except that DCP was comparable between HCC and Cirrhosis groups (p=1.000). All individuals in the control group had FGF-19 levels below the minimum level in the HCC group. Thus, FGF-19 had 100% sensitivity and specificity in differentiating HCC from healthy controls. FGF-19 can discriminate between HCC and Cirrhosis groups at a 140.8 pg/mL cutoff with sensitivity and specificity of 81.8% and 87.9%, respectively. The sensitivity of FGF-19 was higher than AFP, trending toward statistical significance (p=0.095). Combining FGF-19 with AFP, DCP, or both improved sensitivity but decreased specificity. CONCLUSION: FGF-19 is a possible noninvasive serum biomarker for HCC. Its combination with AFP or DCP improves the sensitivity for detecting HCC.

Effect of Fibroblast Growth Factor (FGF) 19 and 21 on Hip Geometry and Strength in Post-menopausal Osteoporosis (PMO).

Fibroblast Growth Factor (FGF) receptor signalling is important for skeletal development. The FGF19 subfamily which includes FGF19 and FGF21 are involved in bone metabolism, although their effects on bone mineral density (BMD) and bone strength remain unclear. To further characterise the influence of these two factors on the skeleton, we studied the association between circulating concentrations of FGF19 and 21 with BMD and parameters of hip geometry and strength in post-menopausal osteoporosis (PMO). The study cohort consisted of 374 women aged (mean [SD]) 68.7[12.3] years with PMO. FGF19 and FGF21 were measured in serum by ELISA. BMD was measured at the lumbar spine (LS), total hip (TH) and femoral neck (FN) (n = 277) by dual energy X-ray absorptiometry (DXA) and hip structural analysis (HSA) parameters (n = 263) at the narrow neck of the femur (NN), Intertrochanter (IT) and Femoral shaft (FS) were derived from DXA scans. FGF19 and 21 were not associated with prevalent fractures or BMD when corrected for covariates; age, BMI, smoking habits and alcohol intake. Log-transformed FGF 21 was negatively associated with HSA parameters including Outer Diameter (OD) (p = 0.019), Cross-sectional area (CSA) (p = 0.01), cross-sectional moment of inertia (CSMI) (p = 0.011), Section modulus (Z) (p = 0.002) and cortical thickness (Co Th) (p = 0.026) at the IT only. CSA, CSMI, Z and Co Th were significantly lower (p < 0.05) in women with FGF21 concentrations greater than the median (> 103.5 pg/ml). Our data suggest that FGF 21 may have potentially adverse effects on the skeleton. Further characterisation is needed, particularly as FGF 21 analogues or agonists may be used to treat obesity-related metabolic disorders.

Fibroblast growth factor 21 inversely correlates with survival in elderly population - the results of the Polsenior2 study.

Fibroblast growth factor 21 (FGF21) is a liver-secreted hormone involved in the regulation of lipid, glucose, and energy metabolism. Its serum concentration increases with age but also is higher in numerous diseases. FGF21 is being investigated for biomarker properties and as a potential therapeutic target. The present study aimed to assess the prognostic value of FGF21 in an older population-based cohort, the PolSenior2 study participants. In the sub-analysis of 3512 individuals, aged 60 and older, stratified according to FGF21 into tertiles, the survival estimate was worse in participants with middle and high levels compared to the lowest tertile. These results were consistent with univariable Cox regression analysis, in which participants in the middle and the high FGF21 tertiles after adjustment for age had 1.43-fold (HR, 1.31; 95% CI, 1.05 - 1.62) and 2.56-fold (HR, 1.94; 95% CI, 1.59 - 2.37) higher risk for mortality, respectively, compared with those in the lowest tertile. In multivariable Cox regression analysis, the highest levels of FGF21 were associated with increased mortality (HR 1.53; 95% CI, 1.22 - 1.92) independently of co-morbidities and blood parameters. These results indicate that higher serum FGF21 concentration is an independent predictor of all-cause mortality in the general population of older adults.

Relationship Between Arterial Stiffness, Measured by Cardio-Ankle Vascular Index, and Uremic Toxins, Vascular Calcification, and Inflammation Markers After Kidney Donation.

OBJECTIVES: This study investigated whether kidney transplant donors experience increased arterial stiffness compared with the general population and how arterial stiffness changes over time. MATERIALS AND METHODS: Our study included 59 kidney transplant donors and 27 healthy volunteers. All subjects underwent cardio-ankle vascular index measurements. We studied fibroblast growth factor23, klotho, monocyte chemoattractant protein-1, N-terminal pro-B-type natriuretic peptide, indoxyl sulfate, and p-cresyl sulfate levels. RESULTS: Cardio-ankle vascular index level was higher in donors 6 to 11 years after donation (8.02 ± 0.24 m/s) than in donors 2 to 6 years after donation (7.02 ± 0.27 m/s) and healthy volunteers (6.65 ± 0.22 m/s). Cardioankle vascular index level was positively correlated with age (r = 0.382, P < .001) and levels of triglyceride (r = 0.213, P = .049), blood urea nitrogen (r = 0.263, P = .014), creatinine (r = 0.354, P = .001), calcium (r = 0.228, P = .035), indoxyl sulfate (r = 0.219, P = .042), p-cresyl sulfate (r = 0.676, P ≤ .001), and monocyte chemoattractant protein-1 (r = 0.451, P ≤ .001) and negatively correlated with estimated glomerular filtration rate (r = -0.383, P < .001). Multiple linear regression analysis revealed that age (P = .026, B = 0.244), mean arterial blood pressure (P < .001, B = 0.446), blood urea nitrogen (P = .006, B = 0.302), creatinine (P = .032, B = 0.236), estimated glomerular filtration rate (P = .003, B = -0.323), fibroblast growth factor-23 (P = .007, B = 0.294), N-terminal pro-B-type natriuretic peptide (P = .005, B = 0.304), and monocyte chemoattractant protein-1 (P ≤ .001, B = 0.434) independently predicted cardio-ankle vascular index levels. CONCLUSIONS: Even without additional risk factors, kidney donors should be followed closely for arterial stiffness and cardiovascular disease, especially in the long-term (>5 years) after kidney transplant.

Impact of Serum Phosphorus on Hemoglobin: A Literature Review.

Phosphorus is a macroelement found in the body, mostly in the bones as crystals of hydroxyapatite. Higher levels are found in patients affected by chronic kidney disease (CKD). Since the early stage of CKD phosphorous excretion is impaired, but the increase of PTH and FGF23 maintains its level in the normal range. In the last decades, the role of FGF23 in erythropoiesis was studied, and now it is well known for its role in anemia genesis in patients affected by conservative CKD. Both Hyperphosphatemia and anemia are two manifestations of CKD, but many studies showed a direct association between serum phosphorous and anemia. Phosphorus can be considered as the common point of more pathogenetic ways, independent of renal function: the overproduction of FGF23, the worsening of vascular disease, and the toxic impairment of erythropoiesis, including the induction of hemolysis.

Fibroblast growth-factor 23-Klotho axis is associated with systemic inflammation and myokine profile in children with chronic kidney disease.

BACKGROUND: Chronic kidney disease is linked to a disturbed fibroblast growth factor-23 (FGF23)-Klotho axis and an imbalance between myostatin and insulin-like growth factor-1 (IGF-1) expression. This cross-sectional study investigates the association of the FGF23-Klotho axis and myokine profile with serum interleukin-6 (IL-6) and their interactions in pediatric patients. METHODS: Serum calcium, phosphorus, 25-hydroxyvitamin D, parathormone, c-terminal FGF23, a-Klotho, myostatin, follistatin, IGF-1, and IL-6 were measured in 53 patients with GFR < 60 ml/min/1,73m2. Myostatin to lean mass (LM) and to IGF-1 ratios were calculated. IL-6 level > 3rd quartile was considered as high. RESULTS: Myostatin, IGF-1, and follistatin were correlated to LM (rs = 0.513, p < 0.001, rs = 0.652, p < 0.001, rs=-0.483, p < 0.001). Myostatin and follistatin were correlated to IGF-1 (rs = 0.340, p = 0.014, rs=-0.385, p = 0.005). Myostatin/LM but not myostatin or myostatin/IGF-1 ratio was significantly higher in CKD 5D patients (p = 0.001,p = 0.844, p = 0.111). Among mineral bone parameters, lnFGF23 was correlated to lnIL-6 (rs = 0.397, p = 0.004) and associated with high IL-6 (OR 1.905, 95% CI 1.023-3.548). Among myokines, myostatin/IGF-1 ratio was correlated to lnIL-6 (rs = 0.395, p = 0.004) and associated with high IL-6 (OR 1.113, 95% CI 1.028-1.205). All associations were adjusted to CKD stage. Myostatin was correlated to lnFGF23 (rs = 0.331, p = 0.025) and myostatin/IGF-1 ratio to lnKlotho (rs=-0.363, p = 0.013), after adjustment for CKD stage, lnIL-6 and other mineral bone parameters. CONCLUSIONS: In pediatric CKD, FGF23 and myostatin/IGF-1 ratio are associated with IL-6, indicating a link between systemic inflammation, mineral bone, and myokine disorders. The correlations between myostatin and FGF23 and between myostatin/IGF-1 and Klotho suggest an interaction between mineral bone and muscle metabolism.

Comparison of fibroblast growth factor 19 concentrations between dogs with and without gallbladder mucoceles.

BACKGROUND: Fibroblast growth factor 19 (FGF19) is an enterohepatic hormone the synthesis of which is stimulated by bile acid activation of the nuclear farnesoid X receptor (FXR) in ileal enterocytes. Increased production of FGF19 downregulates hepatocyte bile acid synthesis and gluconeogenesis, while concurrently upregulating hepatocyte glycogenesis and gallbladder (GB) filling. The physiologic impact of this regulatory cycle is illustrated in cholecystectomized humans, in whom the disturbed meal-related flux of GB bile decreases serum FGF19 concentrations. OBJECTIVE: Determine if serum FGF19 concentrations are lower in dogs with clinical GB mucoceles (GBMs) than in control dogs. ANIMALS: Seven dogs with GBM diagnosed using abdominal ultrasonography, biochemical markers, and GB histopathology. Forty-two control dogs without gastrointestinal or hepatobiliary disorders also were evaluated. Health status of controls was assessed by physical examination and diagnostic hematologic and biochemical test results. METHODS: Prospective cross-sectional study to compare fasting plasma or serum FGF19 concentrations between groups. Concentrations of FGF19 were quantified by a commercially available FGF19 ELISA. RESULTS: Concentrations of FGF19 were significantly lower in dogs with clinical GBM (median, 14.0 pg/mL; range, 12.8-67.2) than in control dogs (median, 145.3 pg/mL; range, 36.5-285.1). CONCLUSIONS AND CLINICAL IMPORTANCE: In dogs, GBM is associated with significantly decreased serum FGF19 concentrations. We speculate that this finding reflects compromised GB contraction and decreased enterohepatic circulation of bile flow. Subnormal FGF19 concentrations may influence bile acid synthesis and hepatic metabolism.

Timing of acute cold exposure determines UCP1 and FGF21 expression - Possible interactions between the thermal environment, thermoregulatory responses, and peripheral clocks.

Thermoregulation is synchronized across the circadian cycle to uphold thermal homeostasis. To test if time-of-day matters for the response to environmental cold exposure, mice were acclimated to thermoneutrality (27 °C) for 2 months were subjected acutely (8 h) to cold ambient conditions (15 °C), whereas controls were maintained at thermoneutral conditions. The thermal exposure was tested in separate groups (N = 8) at three distinct time-of-day periods: in the LIGHT phase (L); the DARK phase (D); and a mix of the two (D + L). The magnitude of UCP1 protein and mRNA induction in brown adipose tissue (BAT) in response to acute cold exposure was time-of-day sensitive, peaking in LIGHT, whereas lower induction levels were observed in D + L, and DARK. Plasma levels of FGF21 were induced 3-fold by acute cold exposure at LIGHT and D + L, compared to the time-matched thermoneutral controls, whereas cold in DARK did not cause a significant increase of FGF21 plasma levels. Cold exposure affected, in BAT, the temporal mRNA expression patterns of core circadian clock components: Bmal1, Clock, Per1, Per3, Cry1, Cry2 Nr1d1, and Nr1d2, but in the liver, none of the transcripts were modified. Behavioral assessment using the Thermal Gradient Test (TGT) showed that acute cold exposure reduced cold sensitivity in D + L, but not in DARK. RNA-seq analyses of somatosensory neurons in DRG highlighted the role of the core circadian components in these cells, as well as transcriptional changes due to acute cold exposure. This elucidates the sensory system as a gauge and potential regulator of thermoregulatory responses based on circadian physiology. In conclusion, acute cold exposure elicits time-of-day specific effects on thermoregulatory pathways, which may involve underlying changes in thermal perception. These results have implications for efforts aimed at reducing risks associated with the organization of shift work in cold environments.

The effects of fibroblast growth factor-23 on diagnosis of cerebral infarction and vertebral basilar artery stenosis☆.

OBJECTIVES: This study aimed to explore the correlation between Fibroblast Growth Factor-23 (FGF23) levels and Cerebral Infarction (CI), and to determine whether there is a significant relationship between FGF23 and the occurrence and severity of CI. METHODS: The study categorized Cerebral Infarction (CI) patients into severe and mild stenosis groups based on vertebrobasilar artery stenosis, using Digital Subtraction Angiography (DSA) and Magnetic Resonance Imaging (MRI). The study compared the levels of Fibroblast Growth Factor-23 (FGF23) in the serum of CI patients and healthy controls using a t-test and evaluated the diagnostic effectiveness of serum FGF23 using a Receiver Operating Characteristic (ROC) curve. Additionally, the study analyzed the correlation between FGF23 levels and CI severity after treatment using the National Institute of Health Stroke Scale score. RESULTS: The study found a significant increase in serum Fibroblast Growth Factor-23 (FGF23) levels in patients with Cerebral Infarction (CI) compared to healthy volunteers, (p < 0.001). A higher serum FGF23 level was observed in the severe stenosis group than in the mild stenosis group (p < 0.001). Furthermore, the study showed that a high FGF23 level at admission was significantly related to more severe symptoms of CI as indicated by the National Institute of Health Stroke Scale (NIHSS) score on the 7th day after treatment (p < 0.001). CONCLUSIONS: This study discovered a correlation between Fibroblast Growth Factor-23 (FGF23) levels, vertebrobasilar artery stenosis, and short-term prognosis in patients who had recently experienced acute Cerebral Infarction (CI).

FGF23-secreting sinonasal tumour presenting with acute subdural haemorrhage and tumour-induced osteomalacia.

A female in her 50s developed a headache, collapsed and was noted to have an acute atraumatic subdural haemorrhage (SDH) requiring surgical evacuation and intracranial pressure-directed therapy. Her background included recurrent epistaxis, severe generalised bone pain and multiple insufficiency fractures and an undifferentiated autoimmune connective tissue disease. Chronic hypophosphataemia, elevated alkaline phosphatase and raised fibroblast growth factor 23 (FGF23) were also noted. An MRI head and subsequent 68Ga CT/positron emission tomography scan demonstrated an intensely avid tumour in the right ethmoid sinus, extending intracranially. Phosphate was aggressively replaced, and alfacalcidol was initiated to circumvent the effects of FGF23 on her kidneys and bone minerals. The tumour was biopsied and then definitively resected via combined endonasal and craniotomy approaches, resulting in good clinical improvement. FGF23 titre and serum phosphate both normalised leaving the diagnosis of a phosphaturic mesenchymal tumour-secreting FGF23, leading to tumour-induced osteomalacia.