Accelerated developmental adipogenesis programs adipose tissue dysfunction and cardiometabolic risk in offspring born to dams with metabolic dysfunction

Abstract

This study determined if a perturbation in in utero adipogenesis leading to later life adipose tissue (AT) dysfunction underlies programming of cardiometabolic risk in offspring born to dams with metabolic dysfunction. Female mice heterozygous for the leptin receptor deficiency (Het_db) had 2.4-fold higher prepregnancy fat mass and in late gestation had higher plasma insulin and triglycerides compared with wild-type (Wt) females (P < 0.05). To isolate the role of the intrauterine milieu, wild-type (Wt) offspring from each pregnancy were studied. Differentiation potential in isolated progenitors and cell size distribution analysis revealed accelerated adipogenesis in Wt pups born to Het_db dams, accompanied by a higher accumulation of neonatal fat mass. In adulthood, whole body fat mass by NMR was higher in male (69%) and female (20%) Wt offspring born to Het_db versus Wt pregnancies, along with adipocyte hypertrophy and hyperlipidemia (all P < 0.05). Lipidomic analyses by gas chromatography revealed an increased lipogenic index (16:0/18:2n6) after high-fat/fructose diet (HFFD). Postprandial insulin, ADIPO-IR, and ex vivo AT lipolytic responses to isoproterenol were all higher in Wt offspring born to Het_db dams (P < 0.05). Intrauterine metabolic stimuli may direct a greater proportion of progenitors toward terminal differentiation, thereby predisposing to hypertrophy-induced adipocyte dysfunction.NEW & NOTEWORTHY This study reveals that accelerated adipogenesis during the perinatal window of adipose tissue development predisposes to later life hypertrophic adipocyte dysfunction, thereby compromising the buffering function of the subcutaneous depot.

Keywords: adipogenesis; developmental programming; lipogenesis; programming.

Graphical abstract

Figure 1.

Heightened cardiometabolic risk in offspring born to metabolically compromised dams. In 12-wk-old chow-fed Wt male (A) and female (B) offspring born to Wt or Het_db pregnancies (Wt/Wt vs. Wt/Het), whole body fat mass was measured by TD-NMR. Fasting plasma triglyceride levels (C), total cholesterol (D), and nonesterified FFA (E) were evaluated in 6-mo-old female offspring using colorimetric assays. Insulin sensitivity (F) was assessed after a 6-h fast by injecting 0.5 IU/kg insulin (IP) and sampling blood glucose from the tail (n = 6–8).

Figure 2.

Increased activity of lipogenic enzymes. Lipidomic analysis was carried out by thin layer gas chromatography in lipids extracted from plasma collected from adolescent male offspring born to Wt or Het_db dams (Wt/Wt vs. Wt/Het) that were fed a control diet (CD) or a high-fat/fructose diet (HFFD). The lipogenic enzyme, stearoyl CoA desaturase (SCD1) catalyzes the conversion of saturated fatty acids (SFA), palmitate and stearate, to monounsaturated fatty acids (palmitoleate and oleate) that are incorporated into complex lipids like triglycerides (A). The desaturation index was calculated by the ratio of palmitic acid (B) and stearic acid (C) to their monounsaturated products. The lipogenic index (D), reflecting the rate of de novo lipogenesis, was calculated as the ratio of palmitic acid (16:0) to linoleic acid (18:2n6). The percentage of total saturated fatty acids (SFA) relative to all lipid species (E) was calculated.

Figure 3.

Adipocyte hypertrophic dysfunction. Cell size distribution calculated with AdipoSoft (Image J) in sections of iSAT of Wt male offspring born to Wt or Het_db dams (Wt/Wt vs. Wt/Het) fed a control diet (CD) (A) or high-fat/fructose diet (HFFD) (B). Representative sections of iSAT (C) in CD or HFFD-fed male offspring (* denotes crown-like structure). Number of crown-like structures (CLS) per slide was quantified in iSAT sections of HFFD-fed male offspring (D). n = 4–5. Hypertrophy of visceral adipocytes after HFFD was determined by quantifying average diameter in H&E sections of gonadal fat (E). *P < 0.05. H&E, hematoxylin-eosin.

Figure 4.

Lipid spillover and suppressed antilipolytic effects of insulin. Postprandial levels of FFA in male (A) and female (B) Wt offspring born to Wt or Het_db dams (Wt/Wt vs. Wt/Het). Postprandial insulin levels in male (C) and female (D) offspring were measured, and the ADIPO-IR was calculated as insulin × FFA for male (E) and female (F) offspring.

Figure 5.

Higher basal and stimulated lipolysis in visceral SAT explants. In explants of inguinal (iSAT) or gonadal white adipose tissue (gWAT) isolated from male Wt offspring born to Wt or Het_db dams (Wt/Wt vs. Wt/Het), glycerol output, reflecting the rate of lipolysis, was measured at baseline (A and B) or after stimulation with isoproterenol (C and D).

Figure 6.

Greater fat mass and accelerated adipogenesis in pups exposed to a metabolically adverse in utero environment. Percent fat mass (A) was measured in 3-wk-old Wt pups born to Wt or Het_db dams (Wt/Wt vs. Wt/Het) using a TD-NMR whole body composition analyzer (all littermates are included; litters are color-coded). Plasma levels of total FFA were measured in Pd21 plasma using thin layer chromatography (B) and correlated to percent fat mass (C). Resistin levels were determined in plasma using an ELISA (D). Cell size distribution was examined using Adiposoft (ImageJ) in H&E-stained sections of Pd21 SAT (E) (n = 6–8). *P < 0.05 Wt/Wt dam vs. Wt/Het dam. H&E, hematoxylin-eosin.

Figure 7.

Higher adipogenic potential in progenitors isolated from neonates exposed to metabolic dysfunction in utero. Adipocyte progenitors were cultured from the stromal vascular fraction (SVF) isolated from iSAT of 3-wk-old Wt offspring born to Wt or Het_db dams and induced to differentiate 48 h after contact inhibition (A). Quantification of lipid droplet formation by optical density of Oil Red O staining (B) and representative images of cells stained with Oil Red O or BODIPY on day 4 of differentiation (C) in progenitors isolated from the SVF of Pd21 iSAT. Protein expression (D) and mRNA expression (E) of adipogenic and lipogenic mediators on D2 of differentiation were determined. *P < 0.05 or **P < 0.001: Wt/Wt dam vs. Wt/Het dam.