elisa  (R&D Systems)

Journal: Frontiers in Endocrinology

Article Title: Metformin increases glycolysis and the stress-induced cytokine GDF15 but not FGF21 in humans

doi: 10.3389/fendo.2026.1797525

Figure Lengend Snippet: Effect of metformin on circulating GDF15 and FGF21. (a) Serum GDF15 (b) and serum FGF21 in healthy individuals fasted for 42 h without (white) and with (black) prior metformin (MET) treatment for seven days. Data is given in mean +/- SEM. #p<0.0001.

Article Snippet: FGF21 was measured on fasting serum samples by the human FGF21 Quantikine ® ELISA assay essentially as described (R&D Systems, Abingdon, UK).

Techniques:

Journal: Frontiers in Endocrinology

Article Title: Metformin increases glycolysis and the stress-induced cytokine GDF15 but not FGF21 in humans

doi: 10.3389/fendo.2026.1797525

Figure Lengend Snippet: Metformin increases mRNA levels of GDF15 in human intestinal Caco-2 cells with no related increase in FGF21. Relative mRNA expression of GDF15, FGF21, SLC2A1 , and the ISR genes ATF4 and DDIT3 in differentiated Caco-2 cells after (a) 6 h or (b) 22 h without treatment (0 mM) or 0.3 mM, 1 mM, or 3 mM metformin treatment at media glucose concentrations of 5.5 mM (c) Raw ct values of GDF15 and FGF21 at 5.5 mM glucose. n = 6-8, 2 wells from 4 independent experiments evaluated in parallel. The data is presented as mean +/- SEM. **p<0.01, ***p<0.001, and ****p<0.0001 as indicated.

Article Snippet: FGF21 was measured on fasting serum samples by the human FGF21 Quantikine ® ELISA assay essentially as described (R&D Systems, Abingdon, UK).

Techniques: Expressing

Journal: Frontiers in Endocrinology

Article Title: Metformin increases glycolysis and the stress-induced cytokine GDF15 but not FGF21 in humans

doi: 10.3389/fendo.2026.1797525

Figure Lengend Snippet: GDF15 secretion is increased in Caco-2 cells upon chronic metformin treatment. (a) GDF15 concentration in media collected from non-treated (0 mM) Caco-2 cells kept in media with glucose concentrations of 5.5 mM, 11 mM, or 25 mM or from cells treated with 0.3 mM, 1 mM, or 3 mM metformin at similar glucose concentrations. (b) A schematic representation of metformin-stimulated GDF15 secretion from Caco-2 cells, where FGF21 protein levels were undetectable. n = 8, 2 wells from 4 independent experiments evaluated in parallel. The data is presented as mean +/- SEM. **p<0.01, determined by two-way ANOVA analysis with Dunnett correction. Figure 3b is created in BioRender. Møller, P. (2025) https://BioRender.com/o87c709 .

Article Snippet: FGF21 was measured on fasting serum samples by the human FGF21 Quantikine ® ELISA assay essentially as described (R&D Systems, Abingdon, UK).

Techniques: Concentration Assay

Journal: Cell Reports Medicine

Article Title: Charting the circulating proteome in ME/CFS using cross-system profiling to uncover mechanistic insights

doi: 10.1016/j.xcrm.2026.102647

Figure Lengend Snippet: Targeted validation and expansion of key findings Antibody-based measurements (Luminex and ELISA) were used to validate and expand on key outcomes from aptamer-based serum proteomics. Luminex data are shown for a panel of 54 serum proteins related to immunity and metabolism, in 83 ME/CFS patients and 29 HC subjects. Samples were analyzed in single assay wells, with intra- and inter-plate technical replicates included for designated samples. (A and B) (A) The directional concordance, and (B) signal consistency (Pearson correlation), between antibody-based and the aptamer-based measurements, per protein. (C–F) (C) The heatmap displays selected affected proteins, including comparison between the three ME/CFS metabotypes (M1, M2, and M3). Expanded ELISA analysis of (D) FGF-21, (E) GDF-15, and (F) C-peptide was performed in larger cohorts ( n = 212 ME/CFS, n = 66 HC). Each sample was assayed in technical duplicate. Boxplot indicates median and IQR (25 th –75 th percentiles), and the whiskers indicate ±1.5×IQR. Statistical comparisons were performed between groups (Welch’s t test with FDR correction, q < 0.05, black asterisks) and stratified by sex and metabotype (one-way ANOVA, p < 0.05, red asterisks, followed by post hoc Welch’s t test with FDR correction, q < 0.05, black asterisks).

Article Snippet: ELISA was performed using Quantikine Ready-to-Use ELISA kits (R&D Systems) for FGF-21 (Cat#: DF2100), C-peptide (Cat#: DICP00), and GDF-15 (Cat#: DG0150).

Techniques: Biomarker Discovery, Luminex, Enzyme-linked Immunosorbent Assay, Comparison

Journal: Frontiers in Nutrition

Article Title: Serum fibroblast growth factor 21 is a novel biomarker of cachexia in chronic liver disease

doi: 10.3389/fnut.2026.1730695

Figure Lengend Snippet: (a) Comparison of serum FGF21, TNF- α , and IL-6 levels between patients with and without cachexia. (b) Comparison of the proportion of cachexia between patients with high and low serum FGF21 levels in the discovery cohort. (c) Comparison of serum FGF21 levels between patients with and without cachexia in the validation cohort. (d) Comparison of the proportion of cachexia cases between patients with high and low FGF21 levels in the validation cohort. FGF, Fibroblast Growth Factor; TNF, Tumor Necrosis Factor; IL, Interleukin.

Article Snippet: The baseline levels of the candidate serum biomarkers, including FGF21, TNF- α , and IL-6, were evaluated using commercial enzyme-linked immunosorbent assays according to the manufacturer’s protocols (FGF21 [Catalog #DF2100], TNF-α, and IL-6: R&D Systems, Minneapolis, MN, United States).

Techniques: Comparison, Biomarker Discovery

Journal: Alzheimer's & Dementia

Article Title: Distinct alterations of adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor binding protein 2 (IGFBP‐2) link dysmetabolism with cognitive decline across the Alzheimer's disease spectrum

doi: 10.1002/alz.71097

Figure Lengend Snippet: Interaction between clinical diagnosis group, age, sex, serum adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor‐binding protein 2 (IGFBP‐2). Association between serum levels of adiponectin, FGF‐21, and IGFBP‐2 and clinical diagnosis before (respectively A, E, and I) and after adjustment for age and sex (respectively B, F, and J). Correlation between adiponectin, FGF‐21, and IGFBP‐2 and age (respectively C, G, and K). Serum levels of metabolites separated by clinical diagnoses and by sex (respectively D, H, and L). Statistical analyses: Values are means ± SEM. Non‐parametric Kruskal–Wallis tests followed by Dunn's post hoc test were performed for group comparisons (A, E, and I). ANCOVA, adjusted for age and sex, was conducted, followed by Dunnett's post hoc tests for pairwise comparisons (B, F, and J). Linear regression between metabolic hormones and age are presented with rho (ρ) and p values (Spearman) (C, G, and K). Two‐way ANOVA was performed using clinical diagnosis and sex as variables (D, H, and L). * p < 0.05; ** p < 0.01; *** p < 0.005; **** p < 0.001. AD, Alzheimer's disease; ANCOVA, analysis of covariance; CH, cognitively healthy; MCI, mild cognitive impairment; SCD, subjective cognitive decline; SEM, standard error of the mean.

Article Snippet: Serum levels of adiponectin, FGF‐21, and IGFBP‐2 were obtained using enzyme‐linked immunosorbent assays (ELISA) following the manufacturer's instructions (Human Total Adiponectin/Acrp30 Quantikine ELISA Kit, Catalog No., DFRP300; Human FGF‐21 Quantikine ELISA Kit, Catalog No., DF2100; Human IGFBP‐2 Quantikine ELISA Kit, Catalog No., DGB200, all from R&D Systems, USA).

Techniques: Biomarker Discovery, Binding Assay

Journal: Alzheimer's & Dementia

Article Title: Distinct alterations of adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor binding protein 2 (IGFBP‐2) link dysmetabolism with cognitive decline across the Alzheimer's disease spectrum

doi: 10.1002/alz.71097

Figure Lengend Snippet: Multiple linear regression for adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor‐binding protein 2 (IGFBP‐2) on clinical and sociodemographic data and blood assessment. Statistical analyses: Red and blue highlighted cells respectively indicate positive and negative correlations. Both unadjusted and adjusted p values (for age and sex) are presented from Spearman correlation analyses. (A) Linear regression between metabolic hormones and selected markers of metabolic status (highlighted in orange in A) are presented with rho (ρ) and p values (Spearman) (B–M). AD, Alzheimer's disease; adj, adjusted for age and sex; Alp, alkaline phosphatase; ALT, alanine transaminase; AST, aspartate; CH, cognitively healthy; HbA1c, glycated hemoglobin; HDL, high‐density lipoprotein; LAP, leukocyte alkaline phosphatase; LDL, low‐density lipoprotein; MCI, mild cognitive impairment; MNA, Mini Nutritional Assessment; SCD, subjective cognitive decline; TG, triglycerides; TSH, thyroid stimulating hormone.

Article Snippet: Serum levels of adiponectin, FGF‐21, and IGFBP‐2 were obtained using enzyme‐linked immunosorbent assays (ELISA) following the manufacturer's instructions (Human Total Adiponectin/Acrp30 Quantikine ELISA Kit, Catalog No., DFRP300; Human FGF‐21 Quantikine ELISA Kit, Catalog No., DF2100; Human IGFBP‐2 Quantikine ELISA Kit, Catalog No., DGB200, all from R&D Systems, USA).

Techniques: Binding Assay

Journal: Alzheimer's & Dementia

Article Title: Distinct alterations of adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor binding protein 2 (IGFBP‐2) link dysmetabolism with cognitive decline across the Alzheimer's disease spectrum

doi: 10.1002/alz.71097

Figure Lengend Snippet: Association between serum adiponectin, fibroblast growth factor 21 (FGF‐21), insulin‐like growth factor‐binding protein 2 (IGFBP‐2), and cognitive scores. Statistical analyses: Red and blue highlighted cells respectively indicate positive and negative correlations. Both unadjusted and adjusted p values (for age and sex) from Spearman correlation analyses are shown. (A) Linear regression between metabolic hormones and selected scores in neuropsychology tests and clinical scales (highlighted in orange in A) are presented with rho (ρ) and p values (Spearman) (B–J). AD, Alzheimer's disease; adj, adjusted for age and sex; BNT, Boston Naming Test—correct spontaneous answers; CH, cognitively healthy; CSF, cerebrospinal fluid; EI score, error interference score; FNAME, Face‐Name Associative Memory Exam; GAI, Geriatric Anxiety Inventory; GDS, Geriatric Depression Scale; LMI, logical memory task, immediate recall from the Wechsler Memory Scale; LMII, logical memory task, delayed recall from the Wechsler Memory Scale; MCI, mild cognitive impairment; MNA, Mini Nutritional Assessment; MoCA, Montreal Cognitive Assessment; PHQ9, Patient Health Questionnaire; RAVLT, Rey Auditory Verbal Learning Test; RTc, reaction time corrected (Card 3); SCD, subjective cognitive decline; TI score, time interference score; T‐MMSE, Telephone Mini‐Mental State Examination; TMT, Trail Making Test Time; WDSST, WAIS Digit Symbol Substitution Test.

Article Snippet: Serum levels of adiponectin, FGF‐21, and IGFBP‐2 were obtained using enzyme‐linked immunosorbent assays (ELISA) following the manufacturer's instructions (Human Total Adiponectin/Acrp30 Quantikine ELISA Kit, Catalog No., DFRP300; Human FGF‐21 Quantikine ELISA Kit, Catalog No., DF2100; Human IGFBP‐2 Quantikine ELISA Kit, Catalog No., DGB200, all from R&D Systems, USA).

Techniques: Binding Assay

Journal: Alzheimer's & Dementia

Article Title: Distinct alterations of adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor binding protein 2 (IGFBP‐2) link dysmetabolism with cognitive decline across the Alzheimer's disease spectrum

doi: 10.1002/alz.71097

Figure Lengend Snippet: Associations between adiponectin, fibroblast growth factor 21 (FGF‐21), insulin‐like growth factor‐binding protein 2 (IGFBP‐2), and AD biomarkers. Statistical analyses: Red and blue highlighted cells respectively indicate positive and negative correlations. Both unadjusted and adjusted p values (for age and sex) from Spearman correlation analyses are shown. (A) Selected linear regression is presented with rho (ρ) and p ‐values (Spearman) (B–D). AD, Alzheimer's disease; adj, adjusted for age and sex; CH, cognitively healthy; MCI, mild cognitive impairment; SCD, subjective cognitive decline.

Article Snippet: Serum levels of adiponectin, FGF‐21, and IGFBP‐2 were obtained using enzyme‐linked immunosorbent assays (ELISA) following the manufacturer's instructions (Human Total Adiponectin/Acrp30 Quantikine ELISA Kit, Catalog No., DFRP300; Human FGF‐21 Quantikine ELISA Kit, Catalog No., DF2100; Human IGFBP‐2 Quantikine ELISA Kit, Catalog No., DGB200, all from R&D Systems, USA).

Techniques: Binding Assay

Journal: Alzheimer's & Dementia

Article Title: Distinct alterations of adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor binding protein 2 (IGFBP‐2) link dysmetabolism with cognitive decline across the Alzheimer's disease spectrum

doi: 10.1002/alz.71097

Figure Lengend Snippet: Multiple linear regression modeling of standardized brain volumes in relation to adiponectin, fibroblast growth factor 21 (FGF‐21), and insulin‐like growth factor‐binding protein 2 (IGFBP‐2). Statistical analyses: Red and blue highlighted cells respectively indicate positive and negative correlations. Both unadjusted and adjusted p values (for age and sex) from Spearman correlation analyses are shown. (A) Selected linear regression between metabolic hormones and magnetic resonance imaging (MRI) metrics are presented with rho (ρ) and p values (Spearman) (B–J). AD, Alzheimer's disease; adj, adjusted for age and sex; CH, cognitively healthy; MCI, mild cognitive impairment; SCD, subjective cognitive decline.

Article Snippet: Serum levels of adiponectin, FGF‐21, and IGFBP‐2 were obtained using enzyme‐linked immunosorbent assays (ELISA) following the manufacturer's instructions (Human Total Adiponectin/Acrp30 Quantikine ELISA Kit, Catalog No., DFRP300; Human FGF‐21 Quantikine ELISA Kit, Catalog No., DF2100; Human IGFBP‐2 Quantikine ELISA Kit, Catalog No., DGB200, all from R&D Systems, USA).

Techniques: Binding Assay, Magnetic Resonance Imaging