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Obesity is classically associated with low serum total and free 25(OH)D. Hypotheses have been advanced to explain this observation but mechanisms remain poorly understood, and notably priming events that could explain such association. We investigated the impact of short-term high fat (HF) diet to investigate early events occurring in vitamin D metabolism. Male C57BL/6J mice were fed with a control diet (control group) and HF diet for 4 days. HF fed mice displayed similar body weight to control mice but significantly increased adiposity, together with a decrease of free 25(OH)D concentrations, which could be explained at least in part by a decrease of Cyp2r1 and Cyp3a11 expression in the liver. An increase of 1,25(OH)2D concentration was also observed and could be explained by a decrease of Cyp24a1 expression observed in the kidney. In white adipose tissue (WAT), no modification of vitamin D metabolites quantity detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Nevertheless, an increase of Cyp2r1 and Cyp27a1 mRNA expression and a decrease of Cyp27b1 mRNA expression could suggest a possible storage of 25(OH)D in WAT at long-term. Our data are supportive of an active role of HF diet in mediating a priming effect leading the well-established perturbation of the vitamin D metabolism associated with obesity, including a decrease of free 25(OH)D and modulation of expression of genes involved in vitamin D metabolism.Inflammation and adipogenesis represent the main pathogenic mechanisms of Graves' orbitopathy (GO), and oxidative stress is a well-known inducer of GO pathology. Endoplasmic reticulum (ER) stress has been suggested as a major contributor to inflammation and reactive oxygen species (ROS) generation. In this study, we investigated the role of the ER-stress chaperone protein, binding immunoglobulin protein (BiP), in GO pathogenesis. Using primary cultures of orbital fibroblasts from patients with GO, we examined the role of BiP in GO pathogenesis by silencing its expression with small-interfering RNA (siRNA). Inflammatory cytokine expression was analysed by Western blotting and ELISA. Intracellular ROS levels induced by hydrogen peroxide or cigarette smoke extract were measured by 5-(and 6)-carboxy-20,70-dichlorodihydrofluorescein diacetate staining and flow cytometry. After adipogenic differentiation in BiP siRNA-transfected cells, the cells were stained with Oil Red O, and the levels of adipogenic transcription factors were determined by Western blot analysis. BiP mRNA expression levels were significantly higher in GO orbital tissues than in non-GO orbital tissues. Silencing BiP attenuated the expression of pro-inflammatory cytokines (interleukin-6, intercellular adhesion molecule-1, and monocyte chemotactic protein-1) in primary cultured GO orbital fibroblasts. Silencing BiP also reduced ROS generation, hyaluronan production, and adipocyte differentiation. These findings suggest that ER stress is involved in the aetiology of GO and that modulation of ER stress has therapeutic potential for GO.A reduction in hepatocyte growth hormone (GH)-signaling promotes non-alcoholic fatty liver disease (NAFLD). However, debate remains as to the relative contribution of the direct effects of GH on hepatocyte function vs indirect effects, via alterations in insulin-like growth factor 1 (IGF1). To isolate the role of hepatocyte GH receptor (GHR) signaling, independent of changes in IGF1, mice with adult-onset, hepatocyte-specific GHR knockdown (aHepGHRkd) were treated with a vector expressing rat IGF1 targeted specifically to hepatocytes. Compared to GHR-intact mice, aHepGHRkd reduced circulating IGF1 and elevated GH. In male aHepGHRkd, the shift in IGF1/GH did not alter plasma glucose or non-esterified fatty acids (NEFA), but was associated with increased insulin, enhanced systemic lipid oxidation and reduced white adipose tissue (WAT) mass. Livers of male aHepGHRkd exhibited steatosis associated with increased de novo lipogenesis, hepatocyte ballooning and inflammation. In female aHepGHRkd, hepatic GHR protein levels were not detectable, but moderate levels of IGF1 were maintained, with minimal alterations in systemic metabolism and no evidence of steatosis. Reconstitution of hepatocyte IGF1 in male aHepGHRkd lowered GH and normalized insulin, whole body lipid utilization and WAT mass. However, IGF1 reconstitution did not reduce steatosis or eliminate liver injury. RNAseq analysis showed IGF1 reconstitution did not impact aHepGHRkd-induced changes in liver gene expression, despite changes in systemic metabolism. These results demonstrate the impact of aHepGHRkd is sexually dimorphic and the steatosis and liver injury observed in male aHepGHRkd mice is autonomous of IGF1, suggesting GH acts directly on the adult hepatocyte to control NAFLD progression.Thyroid hormones are emerging as critical regulators of tumour growth and progression. To assess the contribution of thyroid hormone signalling via integrin αvβ3, expressed on many tumour cells, endothelial cells, and stromal cells, to tumour growth, we compared the effects of thyroid hormones vs tetrac, a specific inhibitor of thyroid hormone action at integrin αvβ3, in two murine xenograft tumour models with and without integrin αvβ3 expression. Integrin αvβ3-positive human anaplastic thyroid cancer cells SW1736 and integrin αvβ3-negative human hepatocellular carcinoma cells HuH7 were injected into the flanks of nude mice. Tumour growth was monitored in euthyroid, hyperthyroid, hypothyroid, and euthyroid tetrac-treated mice. In SW1736 xenografts, hyperthyroidism led to a significantly increased tumour growth resulting in a decreased survival compared to euthyroid mice, while tumour growth was significantly reduced and, hence, survival prolonged in hypothyroid and tetrac-treated mice. Both proliferation and vascularisation, as determined by Ki67 and CD31 immunofluorescence staining, respectively, were significantly increased in tumours from hyperthyroid mice as compared to hypothyroid and tetrac-treated mice. No differences in tumour growth, survival, or Ki67 staining were observed between the different groups in integrin αvβ3-negative HuH7 xenografts. Vascularisation, however, was significantly decreased in hypothyroid and tetrac-treated mice compared to euthyroid and hyperthyroid mice. Apoptosis was not affected in either tumour model, nor were cell proliferation or apoptosis in vitro. Tumour growth regulation by thyroid hormones in αvβ3-positive tumours has important implications for cancer patients, especially those with thyroid dysfunctions and thyroid cancer patients treated with thyrotropin-suppressive L-thyroxine doses.Both estrogen and hydrogen sulfide (H2S) inhibit the proliferation of vascular smooth muscle cells (SMCs) and development of atherosclerosis. In the absence of endogenous H2S as occurred in CSE-knockout (KO) mouse, however, estrogen stimulates the proliferation of vascular SMCs. The underlying mechanisms for this seemingly controversial vascular effect of estrogen are unclear. In the present study, we demonstrated that the stimulatory effect of estrogen on the proliferation of CSE-KO SMCs was suppressed by the inhibitor of insulin-like growth factor-1 receptor (IGF-1R) or knockdown of IGF-1R protein expression. Estrogen downregulated the expression of insulin-like growth factor-1 (IGF-1) and IGF-1R in aortic tissues or aortic SMCs isolated from WT and CSE-KO mice. Furthermore, endogenous H2S downregulated IGF-1R, but upregulated estrogen receptor (ER)-α, in aortic tissues or SMCs. ER-α and IGF-1R were co-located in SMCs and co-immunoprecipitated, which was decreased by H2S. Finally, both endogenous and exogenous H2S induced the S-sulfhydration of IGF-1R, but not ER-α, in WT-SMCs and CSE-KO SMCs, which underlies the decreased formation of IGF-1R/ER-α hybrid in the presence of H2S. Thus, the absence of H2S favors the interaction of estrogen with IGF-1R/ER-α hybrid to stimulate SMCs proliferation. The appreciation of a critical role of H2S in preventing estrogen-induced SMCs proliferation will help better understand the regulation of complex vascular effects of estrogen and sex-related cardiovascular diseases.Preeclampsia (PE), a serious complication of pregnancy, is associated with abnormal trophoblast cell differentiation and autophagy. Herein, we investigated the molecular mechanism underlying the function of ligustrazine (2,3,5,6-tetramethylpyrazine, TMP), a constituent of the traditional Chinese plant medicine Ligusticum wallichii, in PE. Lipopolysaccharide (LPS) was applied to induce a PE rat model, followed by tail vein injection of TMP or lentiviral vector overexpressing microRNA-16-5p (miR-16-5p). Human trophoblast cell line JEG3 was cultured in vitro to construct a PE cell model, followed by t he treatment with different concentrations of TMP, miR-16-5p mimic/inhibitor, or shRNA (shRNA) against insulin growth factor-2 (IGF-2) (sh-IGF-2). Formation of autophagosomes and autophagy-related proteins were then examined. Cell counting kit-8 (CCK-8) and Transwell assays were applied to measure trophoblast cell viability and migration. The binding affinity between miR-16-5p and IGF-2 was verified by dual luciferase report assay. After TMP treatment, autophagosome formation was reduced in trophoblast cells of placental tissue of PE rats, along with downregulation of autophagy-related proteins Light Chain 3 (LC3)-II/LC3-I, Beclin1 (BECN1), and SQSTM1. Moreover, TMP repressed JEG3 cell autophagy, promoted viability and migration concentration-responsively. MiR-16-5p was upregulated in PE, and TMP inhibited miR-16-5p expression. Besides, miR-16-5p downregulated IGF-2 expression to promote cell autophagy and inhibit the viability and migration of JEG3 cells. Further, in vivo experiments validated that TMP impeded PE progression in rats by regulating the miR-16-5p/IGF-2 axis. In summary, TMP inhibits trophoblast cell autophagy and promotes its viability and migration in PE rat model through regulating the miR-16-5p/IGF-2 axis.Aging is a degenerative process that results from the accumulation of cellular and tissue lesions, leading progressively to organ dysfunction and death. Although the biological basis of human aging remains unclear, a large amount of data points to deregulated mitochondrial function as a central regulator of this process. Mounting years of research on aging support the notion that the engendered age-related decline of mitochondria is associated with alterations in key pathways that regulate mitochondrial biology. Particularly, several studies in the last decade have emphasized the importance of the estrogen-related receptor (ERR) family of nuclear receptors, master regulators of mitochondrial function, and their transcriptional coactivators PGC-1s in this context. In this review, we summarize key discoveries implicating the PGC-1/ERR axis in age-associated mitochondrial deregulation and tissue dysfunction. Also, we highlight the pharmacological potential of targeting the PGC-1/ERR axis to alleviate the onset of aging and its adverse effects.Thyroid disorders are the most common endocrine disorders affecting women commencing pregnancy. Thyroid hormone metabolism is strongly influenced by selenium status; however, the relationship between serum selenium concentrations and thyroid hormones in euthyroid pregnant women is unknown. This study investigated the relationship between maternal selenium and thyroid hormone status during pregnancy by utilizing data from a retrospective, cross-sectional study (Maternal Outcomes and Nutrition Tool or MONT study) with cohorts from two tertiary care hospitals in South East Queensland, Australia. Pregnant women (n = 206) were recruited at 26-30 weeks gestation and serum selenium concentrations were assessed using inductively coupled plasma mass spectrometry. https://www.selleckchem.com/products/ipa-3.html Thyroid function parameters were measured in serum samples from women with the lowest serum selenium concentrations (51.2 ± 1.2 µg/L), women with mean concentrations representative of the entire cohort (78.8 ± 0.4 µg/L) and women with optimal serum selenium concentrations (106.

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