Fig 1: Analysis of the effect of IGF2 deletion in young mice on adulthood.A The diagram of IGF2-RNAi and its control lentivirus NC-RNAi were injected into the tail vein of 3-4-week-old mice (1 × 1010pfu/mouse, injected two times for a week, collectively a 4 weeks of injection). B Representative western blot results of IGF2 protein levels in liver tissues when 16 weeks old. C Representative western blot results of IGF2 protein levels in eWAT, iWAT, liver, skeletal muscle, pancreas and kidney tissues. D ELISA results of IGF2 protein level in serum samples, n = 12, ***p < 0.001 (unpaired Student’s t test). E At 16 weeks, liver tissues, iWAT, and eWAT of mice underwent dissection and photography. The representative images were depicted. F–J The whole-body weight, the liver, iWAT, eWAT (n = 12) and quadriceps (n = 6) weight of mice were compared, the p-values have been annotated, n.s not significant (unpaired Student’s t test). K Representative H&E staining of iWAT, eWAT, liver and muscle tissues, and the Oil Red staining of liver and muscle tissues. Magnification: 20×. L, M Adipocyte size distribution curves of eWAT and iWAT between NC-RNAi group mice (gray) and IGF2-RNAi group mice (yellow), respectively. n = 6, *p < 0.05, **p < 0.01, ***p < 0.001 analyzed by a one-way ANOVA with a Tukey’s multiple comparisons test. N, O Plasma TC, TG, HDL-c, LDL-c, ALT, AST, and ALP contents have been identified following injection of IGF2-RNAi and NC-RNAi, n = 6, *p < 0.05, **p < 0.01 (unpaired Student’s t test). P, R The levels of blood glucose underwent measurement at specific times by GTT and ITT assays, n = 6, *p < 0.05, **p < 0.01 analyzed by a two-way ANOVA with Bonferroni’s multiple comparisons test. Q, S The area under curve (AUC) analysis of GTT and ITT assays were conducted in obese mice after IGF2 knockdown, n = 6, Data represent the mean ± SD; ***p < 0.001 by two-tailed, unpaired Student’s t test.
Fig 2: Extreme low or high concentrations of IGF2 were associated with hyperlipidemia, low HDL-c, and central obesity in individual MetS contrasted with control subjects.A, B “U” and inverted “U” shaped relationship between IGF2 levels and the lipid species detected by LC-MS/MS assay utilizing a polynomial fourth order equation to fit the non-linear regression curve, where R² (R-squared) represents the coefficient of determination, and Sy.x represents the standard deviation of the residuals, n = 200. C, D “U” and inverted “U” shaped relationship between IGF2 levels and the lipid species detected by ELISA kit assay utilizing a polynomial fourth order equation to fit the non-linear regression curve, n = 200. E, F Pearson correlation analyses of L-IGF2 levels and H-IGF2 levels with triglyceride conducted by LC-MS/MS assay, n = 200, all p < 0.01. G, H Pearson correlation analyses of L-IGF2 levels and H-IGF2 levels with HDL-c conducted by LC-MS/MS assay, n = 200, all p < 0.05. I, J Pearson correlation analyses of L-IGF2 levels and H-IGF2 levels with triglyceride conducted by ELISA kit assay, n = 200, all p < 0.001. K, L Pearson correlation analyses of L-IGF2 levels and H-IGF2 levels with HDL-c conducted by ELISA kit assay, n = 200, all p < 0.05. M, N Multiple stepwise logistic regression analysis of MetS, HOMA-IR, and other metabolic subgroups (central obesity, hypertension, hyperglycemia, hypertriglyceridemia, and low HDL-c) connected with L-IGF2 and H-IGF2 levels conducted by LC-MS/MS assay and ELISA kit assay, respectively.
Fig 3: Analysis of differentially expressed genes (DEGs) in IGF2-overexpression and deficiency mice.A, E A heat map of log(TPM) expression values of 50 statistically significant differentially expressed genes in the eWAT of mice overexpressing IGF2 and IGF2 knocking down mice with their control mice (T-test q-value < 0.05 adjusted with FDR multiple hypothesis correction), n = 2 with 2 replicate sequencing. B, C GO and KEGG assay of DEGs in the eWAT of mice overexpressing IGF2 and control mice. D The validated differential expression levels of genes associated with adipogenesis, lipogenesis, and lipolysis in the eWAT of mice overexpressing IGF2 and control mice, using Ppia as internal controls, n = 6. *p < 0.05, **p < 0.01 by two-tailed, unpaired Student’s t test. F, G GO and KEGG assay of DEGs in the eWAT of mice subjected to IGF2-RNAi and control mice. H The validated differential expression levels of genes associated with adipogenesis, lipogenesis, and lipolysis in the eWAT of mice subjected to IGF2-RNAi and control mice, using Ppia as internal controls respectively, n = 6. Data represent the mean ± SD; *p < 0.05, **p < 0.01, ***p < 0.001 by two-tailed, unpaired Student’s t test.
Fig 4: Effects of IGF2 overexpression and knockdown on pancreatic islet size, insulin secretion and PI3K/Akt-AMPK pathway in adipose tissues.A Representative images of insulin immunohistochemistry (IHC) and immunofluorescence (IF) analysis of pancreatic islets in mice overexpressing IGF2 (Ad-IGF2) or having IGF2 knocked out (IGF2-RNAi) as well as controls (Ad-GFP and NC-RNAi). Scale bars represent 100 μm. B Quantification of islet beta cell mass among the different treatment groups. C Quantification of the proportion of insulin-positive area to islet area per mouse pancreas section among the different treatment groups. D Average optical density of insulin immunostaining within islets. E Mean fluorescence intensity of insulin immunostaining within islets. F, G Serum insulin, IGF1, and IGF2 concentrations in mice overexpressing IGF2 or having IGF2 knocked out as well as controls. H–K The expression changes of IGF2 and insulin were detected using Western blot of the collected cell culture supernatant from a pancreatic islet beta cell line, βTC after overexpression and knockdown of IGF2, respectively. Transferrin serves as an internal control for the supernatant. L, M Glucose-stimulated insulin secretion (GSIS) in βTC cells and INS-1 cells after IGF2 overexpression treatment. N, O Glucose-stimulated insulin secretion (GSIS) in βTC cells and INS-1 cells after IGF2 knockdown treatment. P INSR, IGF1R, p-P13K, p-Akt, Akt, p-AMPKα, AMPKα, and IGF2 protein expression levels in adipose tissues after IGF2 overexpression and knockdown treatment by western blot assays. Q, R Quantification of p-P13K/PI3K, p-Akt/Akt, p-AMPKα/AMPKα, INSR and IGF1R compared with β-actin levels in adipose tissues after IGF2 overexpression and knockdown treatment, respectively. S INSR, IGF1R, p-P13K, p-Akt, Akt, p-AMPKα, AMPKα, and IGF2 protein expression levels in 3T3-L1 adipocytes after IGF2 overexpression and knockdown treatment by western blot assays. T, U Quantification of p-P13K/PI3K, p-Akt/Akt, p-AMPKα/AMPKα, INSR and IGF1R compared with β-actin levels in 3T3-L1 adipocytes after IGF2 overexpression and knockdown treatment, respectively. The number of replicates (n) is illustrated by a bar chart with individual data points. Data represent the mean ± SD; *p < 0.05, **p < 0.01, ***p < 0.001 by two-tailed, unpaired Student’s t test in this Figure.
Fig 5: Gene-level association scores for IGF2 based on the MAGMA analysis of common variants.The different colors and patterns in the image represent different traits or diseases that have been studied in relation to the IGF2 gene. The vertical lines indicate the strength and direction of the association between each trait/disease and the IGF2 gene. The dots represent significant associations, where the association score has reached a statistically significant level after correction for multiple testing. Common variants in IGF2 are associated with weight, HbA1c, BMI, and type 1 diabetes (p < 0.05).
Supplier Page from Abcam for Recombinant mouse IGF2 protein (Animal Free)