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 (Hetdb) had 2.4-fold higher pre-pregnancy fat mass and in late gestation had higher plasma insulin and triglycerides, compared to 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 Hetdb 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 Hetdb vs. 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 Hetdb dams (p < 0.05). Intrauterine metabolic stimuli may direct a greater proportion of progenitors toward terminal differentiation, thereby predisposing to hypertrophy-induced adipocyte dysfunction.

No abstract

Background Extensive protein synthesis in multiple myeloma (MM) cells renders them vulnerable to proteasome inhibitors (PI), a cornerstone of anti-myeloma therapy. However, relapse is inevitable and PI resistance remains a major barrier to improving outcomes. Adaptive responses to PI include upregulation of autophagy, another major degradation pathway in cells. We hypothesised that autophagy inhibition increases cell death and impedes recovery of MM cells exposed to Carfilzomib (K), a second generation PI effective in newly diagnosed and relapsed/refractory MM. Methods: Human myeloma cell lines (HMCL) and patient samples were exposed to a 1-hour pulse of K to mimic pharmacokinetics, ± autophagy inhibitors (AI) vacuolar protein sorting kinase 34 inhibitor (VPS34i) or unc-51 like autophagy initiating kinase inhibitor (ULKi). Apoptosis was assessed by Annexin V/Propidium iodide (AnV/PI) flow cytometry (FC) and autophagic flux by western blotting (WB) and FC for light chain 3B (LC3B) ± bafilomycin (B). Cell cycle was examined by FC using KI67/PI. Results: Basal autophagic flux was seen in all HMCL (MM1s, H929, KMS12BM) tested (±B). Autophagic flux increased in response to K: MM1s mean fluorescence intensity (MFI) control (CTL) 318±28 vs K 567±72, (mean±SEM),p=0.01, n=6). Autophagy was inhibited in all 3 HMCL with AI. Combined exposure to K and AI (VPS34i or ULKi) increased time dependent apoptosis in all HMCL tested: MM1s 31±8% (K) vs 58±9% (K+VPS34i), p=0.03, (n=3), and 13±0.4% (K) vs 63±16% (K+ULKi), p=0.03 (n=3), (K 10nM, AI 1uM) 48 hours(h) post K exposure. Basal autophagic flux was detected in all CD138+ primary MM patient samples tested by LC3B FC assay (MFI CTL B- 407±57 vs B+ 1081±125, p&lt;0.0001, n=14). This increased in response to K: CTL B- 407±57 vs K B- 862±224, p=0.03, n=14. VPS34i alone reduced viable cell numbers in 26/33 primary samples (% viable cells relative to starting viable MM cell number at day 0: CTL 99±14% vs VPS34i 71±12%, p&lt;0.0001 at 48h), and cell loss correlated with basal autophagic flux (r=0.9, Pearson's correlation coefficient, p=0.0003, n=10). Addition of VPS34i to K increased loss of viable CD138+ cells (n=33) (Fig 1). Both apoptosis with K and enhanced cell death with K+VPS34i correlated with basal autophagic flux (r=0.8, p=0.0005 and r=0.8, p&lt;0.0001 respectively), but no correlation was seen with previous therapy, disease stage, or adverse risk by cytogenetics or ISS stage. K treated MM1s cells were examined for kinetics of ubiquitinated protein build up and autophagic induction by WB. Increased ubiquitinated proteins were detectable up to 24h post K pulse, whilst autophagic flux increased up to 72h but returned to baseline thereafter (n=3). MM1s cells were treated with K±VPS34i for up to 7 days and apoptosis, absolute cell number and cell cycle assessed. In K treated cells, apoptosis was maximal at 72h but declined thereafter. Viable cell numbers fell initially but increased after 96h, indicating cell recovery. However, in MM1s cells treated with K+VPS34i/ULKi, apoptosis was enhanced with a rapid loss of viable cells (Fig 2) and viable cell numbers remained low at all timepoints (Fig 3). Cell cycle assays confirmed persistent G0/G1 arrest in MM1s cells treated with K+VPS34i or ULKi at all timepoints, whilst cell proliferation recovered in K treated cells on day 3, (15±3% cells in S/G2M in K treated cells vs 2±0.4% with K+VPS34i, p=0.02, n=4, 11±3% in S/G2M with K vs 1± 0.7% with K+ULKi, p=0.04, n=3, day 4)(Fig 4). To confirm that effects of AI were mediated via autophagy, KMS28PE (ATG12 null HMCL) were treated with K±VPS34i. These autophagy depleted cells showed limited basal or K induced autophagic flux and addition of VPS34i to K had no effect on apoptosis or cell cycle. Conclusion MM cells displayed active autophagic flux that increased with K treatment. Inhibition of autophagy increased K induced apoptosis, prolonged K-induced cell cycle arrest and prevented MM cell recovery. Addition of AI to K increased cytotoxicity in patient samples and many patients showed sensitivity to AI alone; these effects correlated with basal autophagic flux. These data suggest that autophagy plays a vital role in cell recovery from proteasome inhibition independent of proteotoxic stress. Dual inhibition of the proteasome and autophagosome may therefore help overcome PI resistance, which remains an unmet need in MM. Figure 1 Figure 1. Disclosures Auner: Takeda, Karyopharm: Other: Advisory role; Amgen: Research Funding; Janssen: Speakers Bureau. Khwaja: Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Astellas: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Yong: Sanofi: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Takeda: Honoraria; GSK: Honoraria; Amgen: Honoraria; BMS: Research Funding; Autolus: Research Funding.

Objectives Determine the role of adipose tissue dysfunction in programming of cardiovascular disease risk in offspring born to dams with metabolic dysfunction. Methods The female mouse heterozygous for leptin receptor deficiency (Hetdb) was used as a model of maternal metabolic dysfunction. These females exhibit higher adiposity, dyslipidemia and hyperinsulinemia during pregnancy. Our data show that this model reproduces programming of early‐onset cardiovascular disease risk reported in human offspring born to obese or diabetic mothers. We sought to test the hypothesis that programming of cardiovascular disease risk is attributable to perturbed adipose tissue development leading to later‐life adipose tissue dysfunction. Wild type (Wt) offspring from both Wt and Hetdb pregnancies were studied as neonates and adults. At 7 weeks of age, offspring were placed on either a control or high fat/sugar (HF/HS) diet. Adipogenic potential was examined in preadipocytes isolated from the stromal vascular fraction (SVF) of inguinal subcutaneous adipose tissue (iSAT) in both neonatal and adult Wt offspring. After induction of differentiation, Oil Red O staining was used to measure lipid droplet accumulation and qPCR was used to measure adipogenic markers. Flow cytometry was utilized to quantify adipogenic progenitors in SVF. Adipokine secretion was measured with ELISA. Several indices of adipose tissue function were measured in adult offspring, including adipose tissue insulin resistance (Adipo‐IR). Results NMR whole‐body fat mass was 1.3 fold higher (p < 0.01) and plasma resistin levels were 1.7 fold higher (p < 0.01) in Wt neonates born to Hetdb pregnancies. The iSAT of Wt neonates and adults born to Hetdb vs. Wt dams exhibited a shift in the cell size distribution from smaller adipocytes to larger adipocytes (p < 0.05), indicating that adipogenesis was accelerated in the iSAT of Hetdb neonates. The percentage of CD31‐CD45‐CD29+CD34+ viable SVF cells was higher in neonates from the Hetdb vs. Wt pregnancy. Preadipocytes isolated from Hetdb offspring exhibited a pro‐adipogenic phenotype in early life that persisted into adulthood. After HF/HS feeding, preadipocytes isolated from Wt female (p < 0.05) and male (p < 0.05) adult offspring born to Hetdb pregnancies accumulated more lipid during differentiation. Heightened adipogenesis in adult offspring was also accompanied by impaired insulin‐stimulated inhibition of lipolysis. Conclusions Adipose tissue dysfunction in offspring born to metabolically adverse pregnancies stems from in utero programming of a pro‐adipogenic phenotype in preadipocytes. Support or Funding Information Canadian Institutes of Health Research, Alberta Children’s Hospital Research Institute, Heart & Stroke Foundation of Canada and Libin Cardiovascular Institute of Alberta