Estrogen restores disordered lipid metabolism in visceral fat of prediabetic mice

Figure 1 Estrogen mitigates 20% lard-enriched high-fat diet-induced visceral adiposity. A: Body weight; B: Growth rate of body weight; C: Fat weight; D: Ratio of peri-gonadal/subcutaneous fat weight. ^aP < 0.05, ^bP < 0.01, ^cP < 0.001. n = 7-8. ND: Normal chow diet; HFD: High-fat diet; OVX: Ovariectomy; E2: 17β-estradiol; NS: Not significant.

Figure 2 Estrogen reverses high-fat diet-induced disordered glucose metabolism. A: Random blood glucose; B: Area under the curve (AUC) of A; C: Intra-peritoneal glucose tolerance test; D: AUC of C; E: Intra-peritoneal insulin tolerance test; F: AUC of E. ^bP < 0.01, ^CP < 0.001. n = 7-8. ND: Normal chow diet; HFD: High-fat diet; OVX: Ovariectomy; E2: 17β-estradiol; AUC: Area under the curve; NS: Not significant.

Figure 3 Estrogen restores high-fat diet-induced aberrant signaling pathways in visceral adipose tissue. A: Top ten significantly enriched pathways based on down-regulated genes by high-fat diet (HFD) + ovariectomy (OVX) compared to HFD + sham operation; B: Top ten significantly enriched pathways based on up-regulated genes by HFD + OVX + 17β-estradiol (E2) compared to HFD + OVX; C: Top ten significantly enriched pathways based on up-regulated genes by HFD + OVX compared to HFD + sham operation; D: Top ten significantly enriched pathways based on down-regulated genes by HFD + OVX + E2 compared to HFD + OVX. n = 3-4.

Figure 4 Estrogen protects mice from more calorie-dense high-fat diet-induced adiposity. A: Body weight; B: Peri-gonadal fat weight; C: Subcutaneous fat weight; D: Fat mass; E: Lean mass; F: Body fluid. ^aP < 0.05, ^bP < 0.01. n = 5-6. HFD: High-fat diet; OVX: Ovariectomy; E2: 17β-estradiol; NS: Not significant.

Figure 5 Validation of estrogen protection of high-fat diet-induced disordered fat metabolism by RT-PCR in visceral adipose tissue of more calorie-dense high-fat diet-fed mice. A: Expression of fatty acid biosynthetic genes including Fasn, Acaca, and Oxam; B: Expression of fatty acid oxidative genes including Cpt1a, Cpt2, and Lipe. ^aP < 0.05, ^bP < 0.01, ^cP < 0.001. n = 5-6. HFD: High-fat diet; OVX: Ovariectomy; E2: 17β-estradiol; NS: Not significant.

Figure 6 Estrogen reverses high-fat diet-induced leptin resistance and inhibits adipocyte hypertrophy. A: Plasma levels of leptin; B: Lepin gene expression in visceral adipose tissue (VAT); C: HE staining of VAT. ^aP < 0.05. n = 5-7. HFD: High-fat diet; OVX: Ovariectomy; E2: 17β-estradiol; NS: Not significant.