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Background: Polycystic ovary syndrome’s (PCOS) main feature is hyperandrogenism, which is linked to a higher risk of metabolic disorders in women. Gene expression analyses in adipose tissue and skeletal muscle reveal dysregulated metabolic pathways in women with PCOS, but these differences do not necessarily lead tochanges in protein levels and biological function. Methods: To advance our understanding of the molecular alterations in PCOS, we performed global proteomic and phosphorylation site analysis using tandem mass spectrometry. Adipose tissue and skeletal muscle were collected at baseline from 10 women with and without PCOS, and in women with PCOS after 5 weeks of treatment with electrical stimulation. Results: Perilipin-1, a protein that typically coats the surface of lipid droplets in adipocytes, was increased whereas proteins involved in muscle contraction and type I muscle fiber function were downregulated in PCOS muscle. Proteins in the thick and thin filaments had many altered phosphorylation sites, indicating differences in protein activity and function. The upregulated proteins in muscle post treatment were enriched in pathways involved in extracellular matrix organization and wound healing, which may reflect a protective adaptation to repeated contractions and tissue damage due to needling. A similar, albeit less pronounced, upregulation in extracellular matrix organization pathways was also seen in adipose tissue. Conclusions: Our results suggest that hyperandrogenic women with PCOS have higher levels of extramyocellular lipids and fewer oxidative insulin-sensitive type I muscle fibers. These could be key factors leading insulin resistance in PCOS muscle while electric stimulation-induced tissue remodeling may be protective., CC BY 4.0 DEED5 January 2024Corresponding author: Anna Benrick, University of Gothenburg, Institute of Neuroscience and Physiology, Department of Physiology, Box 432, 405 30 Gothenburg, Sweden. Phone: +46 (0)709490148. E-mail: anna.benrick@gu.seFunding: A.B. holds funding from the Swedish Research Council (2020-02485), E.SV. holds funding from the Swedish Research Council (2022-00550), the Novo Nordisk Foundation (NNF22OC0072904), and I.W.A. holds funding from the Swedish Research Council (2020-01463), Mary von Sydow Foundation, Diabetes Wellness Sverige, and EFSD//European Research Programme on ‘New Targets for Diabetes or Obesity-related Metabolic Diseases’ supported by MSD 2022, and J.N. holds funding from IngaBritt and Arne Lundberg Research Foundation.Manuskript i medRxiv: DOI: 10.1101/2023.03.08.23286896

Adiponectin administration to pregnant mice decreases nutrient transport and fetal growth. An adiponectin deficiency, on the other hand, as seen in obese women during pregnancy, alters fetal growth; however, the mechanism is unclear. To determine the role of adiponectin on placenta function and fetal growth, we used adiponectin knockout, adiponectin heterozygote that displays reduced adiponectin levels, and wild-type mice on a control diet or high fat/high sucrose (HF/HS) diet. Triglycerides (TGs) in the serum, liver, and placenta were measured using colorimetric assays. Gene expression was measured using quantitative RT-PCR. Adiponectin levels did not affect fetal weight, but it reduced adiponectin levels, increased fetal serum and placenta TG content. Wildtype dams on a HF/HS diet protected the fetuses from fatty acid overload as judged by increased liver TGs in dams and normal serum and liver TG levels in fetuses, while low adiponectin was associated with increased fetal liver TGs. Low maternal adiponectin increased the expression of genes involved in fatty acid transport; Lpl and Cd36 in the placenta. Adiponectin deficiency does not affect fetal growth but induces placental dysfunction and increases fetal TG load, which is enhanced with obesity. This could lead to imprinting effects on the fetus and the development of metabolic dysfunction in the offspring., CC BY 4.0Attribution 4.0 International (CC BY 4.0)© 2022 by the authors. Licensee MDPI, Basel, Switzerland.Correspondence: anna.benrick@gu.se or anna.benrick@his.seThis research was funded by the Swedish Research Council (2013-07107, 2020-02485, 2020-01463), the NovoNordisk Foundation (NNF19OC0056601), the Swedish Diabetes Foundation (DIA2019-419), the Diabetes Research and Wellness Foundation, Magnus Bergvall Foundation (2018-02891), Åke Wiberg Foundation (M17-0113), Adlerbertska Foundation (E 2017/26), Hjalmar Svensson Foundation (HJSV2017070), and The Royal Society of Arts and Sciences in Gothenburg (2019-330).

Here we have investigated the role of the protein caveolin 1 (Cav1) and caveolae in the secretion of the white adipocyte hormone adiponectin. Using mouse primary subcutaneous adipocytes genetically depleted of Cav1, we show that the adiponectin secretion, stimulated either adrenergically or by insulin, is abrogated while basal (unstimulated) release of adiponectin is elevated. Adiponectin secretion is similarly affected in wildtype mouse and human adipocytes where the caveolae structure was chemically disrupted. The altered ex vivo secretion in adipocytes isolated from Cav1 null mice is accompanied by lowered serum levels of the high-molecular weight (HMW) form of adiponectin, whereas the total concentration of adiponectin is unaltered. Interestingly, levels of HMW adiponectin are maintained in adipose tissue from Cav1-depleted mice, signifying that a secretory defect is present. The gene expression of key regulatory proteins known to be involved in cAMP/adrenergically triggered adiponectin exocytosis (the beta-3-adrenergic receptor and exchange protein directly activated by cAMP) remains intact in Cav1 null adipocytes. Microscopy and fractionation studies indicate that adiponectin vesicles do not co-localise with Cav1 but that some vesicles are associated with a specific fraction of caveolae. Our studies propose that Cav1 has an important role in secretion of HMW adiponectin, even though adiponectin-containing vesicles are not obviously associated with this protein. We suggest that Cav1, and/or the caveolae domain, is essential for the organisation of signalling pathways involved in the regulation of HMW adiponectin exocytosis, a function that is disrupted in Cav1/caveolae-depleted adipocytes., Funding Agencies|Swedish Diabetes Foundation [DIA2015-062, DIA2017-273, DIA2018-358]; Novo Nordisk FoundationNovo Nordisk Foundation; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Research CouncilSwedish Research Council [2013-7107, 2017-00792, 2019-01239]; AstraZenecaAstraZeneca