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Lindgren, E.

Publications and source records attributed to Lindgren, E..

6 recordsLinked to original sources

Cell type-resolved transcriptomic map of skeletal muscle in women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with skeletal muscle insulin resistance, fibrosis, and lipotoxicity, yet the cellular origins remain unknown. Here, we present a comprehensive cellular atlas of skeletal muscle from hyperinsulinemic and hyperandrogenic women with PCOS and controls of similar age, weight, and BMI. Analysis of 72,247 nuclei from 19 biopsies revealed cell-type-specific dysregulation in PCOS, with fiber-type-specific metabolic impairment, converging with pro-fibrotic reprogramming of fibro-adipogenic progenitors (FAPs) and enhanced FAP-myofiber crosstalk, characterized by enhanced collagen and laminin signaling. Metformin intervention for 16-weeks selectively reversed PCOS-associated transcriptional dysregulation in FAPs, revealing heterogeneous cellular responses in skeletal muscle. In vitro, PCOS myotubes retained metabolic dysfunction, yet show normalized glucose responsiveness, indicating plasticity despite metabolic memory. Systemic hyperinsulinemia and hyperandrogenemia correlated with transcriptional signatures in muscle fibers and FAPs, linking endocrine imbalance to pro-fibrotic remodeling. These findings identify novel therapeutic targets beyond conventional insulin-sensitizing approaches. Highlights- First single-nuclei atlas of human skeletal muscle in women with PCOS - FAPs subpopulations display activated pro-fibrotic phenotype - Metformin selectively targets distinct cell populations - Hyperinsulinemia and hyperandrogenemia correlate with transcriptional signatures of skeletal muscle fibers and FAPs

physiology↗

Hypoadiponectinemia does not enhance anxiety-like behaviour in a lean PCOS-like mouse model

Polycystic ovary syndrome (PCOS) is characterized by reproductive and metabolic disturbances and is associated with increased symptoms of anxiety and depression. Circulating adiponectin, an insulin-sensitizing adipokine, is reduced in women with PCOS, and low adiponectin has been linked to impaired mental health, particularly in females. We investigated whether low serum adiponectin is associated with impaired mental health in women with PCOS and whether adiponectin deficiency exacerbates anxiety-like behaviour in a PCOS-like mouse model. Serum adiponectin was measured in women with (n=179) and without PCOS (n=228), stratified by body mass index (BMI). Health-related quality of life was assessed using the SF-36, generating physical and mental component scores. In parallel, the prenatal androgenization (PNA) PCOS-like mouse model was combined with adiponectin-deficient mice (APNhet) to assess the impact of reduced adiponectin on anxiety-like behaviour with and without prenatal androgen exposure. Women with PCOS had lower total and high molecular weight adiponectin levels compared with controls. Adiponectin positively correlated with mental component scores in women with BMI <30, but not in those with obesity. Free testosterone was inversely correlated with adiponectin. In mice, PNA induced anxiety-like behaviour, however, reduced adiponectin did not exacerbate this phenotype. Although APNhet PNA mice showed 65% lower serum adiponectin levels and reproductive dysfunction, they displayed improved metabolic function. Unlike women with PCOS, adult PNA mice were not hyperandrogenic. These findings suggest that adiponectin is associated with mental health in non-obese women, but reduced adiponectin alone does not induce anxiety-like behaviour in the absence of hyperandrogenism. The differing patterns observed across BMI categories, as well as between the human cohort and experimental data, underscore the complexity of the mechanisms underlying mental health disturbances in PCOS.

animal behavior and cognition↗

Implantation failure linked to altered uterine NK cells in PCOS-like mice

Uterine NK (uNK) cells are essential for reproductive function, yet little is known how they are affected in polycystic ovary syndrome (PCOS), despite the strong association between PCOS and reproductive complications. We demonstrate that implantation failure coincides with distinct phenotypic alterations of uNK cells in a PCOS-like mouse model. Hyperandrogenism caused an increased influx of conventional NK (cNK) cells into the uterus, which contributed to an augmented uNK cell population, while tissue-resident NK (trNK) cells remained unchanged. Notably, CD69+ trNK cells were reduced and seemingly compensated by an upregulated expression of CD69 on cNK cells in the uterus. The maturation of uNK cells was disrupted and plausibly linked to an inability of cNK cells to convert into trNK cells. The inhibited maturation was associated with a reduced expression of the inhibitory receptor NKG2A, demonstrating an impaired education of uNK cells. This disruption of uNK cells could contribute to endometrial dysfunction and may be an underlying factor to reproductive comorbidities such as implantation failure, miscarriage and pre-eclampsia in PCOS.

immunology↗

Divergent roles of SOX2 in human and mouse germ cell specification related to X-linked gene dosage effects

Human primordial germ cell-like cells (hPGCLCs) can be generated from pluripotent stem cells (PSCs) but the differentiation efficiency of female hPSCs is often lower than that of male hPSCs. Moreover, Klinefelter Syndrome (KS), a condition characterized by an extra X-chromosome in males, often presents the failure of germline specification and infertility. In this study, we investigate how X-linked gene dosage affects hPGCLCs specification potential in both healthy and diseased conditions. We reveal that the X-chromosome plays a multifaceted role in modulating hPGCLCs induction. The inhibitory effects on TGF-beta/Activin A and BMP pathways by escape genes IGSF1 and CHRDL1, respectively, are demonstrated by the increased yield of hPGCLCs with knockdown experiments. Importantly, our results identified the intriguing role of SOX2 that is upregulated by the escape gene USP9X in hPGCLCs specification, highlighting a species-specific difference from the mouse model. The elevated USP9X-SOX2 regulatory axis profoundly influences cellular metabolism, mitochondrial morphology, and progenitor competence, thereby affecting hPGCLCs induction. Furthermore, the inability to downregulate SOX2 and upregulate SOX17 in response to BMP signaling impedes downstream gene activation due to motif binding competition. These findings shed novel insights into the hPGC specification by elucidating the differential roles of SOX2 versus SOX17 between mice and humans, influenced by X-linked gene dosage effects. Additionally, our results offer potential applications for improving the induction and survival efficiency of hPGCLCs from hPSCs, facilitating disease modeling and mechanistic studies. HighlightsO_LIDownregulation of three X-linked genes, i.e. IGSF1, CHRDL1 and USP9X, enhanced the differentiation efficiency of hPGCLCs C_LIO_LISOX2 as a downstream of human-specific escape gene USP9X plays a multifacet role against hPGCLCs specification C_LIO_LIFailure to timely downregulate SOX2 and upregulate SOX17 interferes downstream gene activation likely due to motif binding competition C_LI

cell biology↗

Androgens modulate the immune profile in a mouse model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is associated with a low-grade inflammation, but it is unknown how hyperandrogenism, the hallmark of PCOS, affects the immune system. Using a well-established PCOS-like mouse model, we demonstrate that androgen exposure affects immune cell populations in reproductive, metabolic, and immunological tissues differently in a site-specific manner. Co-treatment with flutamide, an androgen receptor antagonist, prevents most of these alterations, demonstrating that these effects are mediated through androgen receptor activation. Dihydrotestosterone (DHT)-exposed mice display a drastically reduced eosinophil population in uterus compared to controls, coupled with lower levels of eotaxin (CCL11), suggesting a reduced recruitment from blood. Decreased frequencies of eosinophils were also seen in visceral adipose tissue (VAT). A higher expression level of CD69, a marker of activation or tissue residency, was consistently found on natural killer (NK) cells in all analyzed tissues. However, a higher frequency of NK cells and elevated levels of IFN-{gamma} and TNF- were only seen in uteri of androgen-exposed mice, while NK cell frequencies were unaffected in all other analyzed compartments. Distinct alterations of macrophages in ovaries, uterus and VAT were also found in DHT-exposed mice and could potentially be linked to PCOS-like traits of the model. Indeed, androgen-exposed mice were insulin resistant and displayed an aberrant immune profile in VAT, albeit unaltered fat mass. Collectively, we demonstrate that hyperandrogenism causes tissue-specific alterations of immune cells in reproductive organs and VAT, which could have considerable implications on tissue function and contribute to the reduced fertility and metabolic comorbidities associated with PCOS.

immunology↗

Dissecting the Impact of Maternal Androgen Exposure on Offspring Health through Targeting the Androgen Receptor in Developmental Programming

Women with polycystic ovary syndrome (PCOS) exhibit sustained elevation in circulating androgens during pregnancy, an independent risk factor linked to pregnancy complications and adverse neonatal outcomes. Yet, further investigation is required to understand the precise mechanisms and the impact on cell-type specific placental dysfunction. To explore these dynamics, a PCOS-like mice model was induced with continuous androgen exposure throughout pregnancy, mimicking the human-PCOS. This resulted in impaired placental and embryonic development, leading to mid-gestation lethality. Co-treatment with the androgen receptor blocker, flutamide, prevented this lethality. Comprehensive analysis using whole-genome bisulfite and RNA sequencing revealed the diminished proportion of trophoblast precursors by downregulation of Cdx2. The absence of Gcm1, Synb, and Prl3b1 further resulted in decreased numbers of syncytiotrophoblasts and sinusoidal trophoblast giant cells, leading to observed compromised placenta labyrinth formation. Importantly, human trophoblast organoids exposed to androgens exhibited analogous alterations, highlighting impaired trophoblast differentiation as a key feature in PCOS-related pregnancy complications. Remarkably, all effects were mediated through the androgen receptor pathways, as demonstrated by comparable offspring phenotypes to controls when treated with flutamide. These findings provide novel insight into the PCOS-related pregnancy complications, and potential cellular targets for future treatment.

physiology↗