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Interactions between female metabolic status, immune response, and reproductive system functioning are complex and not fully understood. We hypothesized that chemerin, considered a hormonal link between the above-mentioned processes, influences endometrial functions, particularly cytokine secretion and signaling. Using porcine endometrial explants collected during early pregnancy and the estrous cycle, we investigated chemerin effects on the secretion of interleukins (IL-1β, IL-6, and IL-8), leukemia inhibitory factor, tumor necrosis factor α, transforming growth factor α, and protein abundances of their respective receptors. Our results demonstrate chemerin modulation of cytokine secretion and receptor expression, with effects dependent on the stage of pregnancy and dose of chemerin. Furthermore, chemerin influences the phosphorylation of stress-activated protein kinase/Jun-amino-terminal kinase and nuclear factor kappa-light-chain-enhancer of activated B cells in the endometrium. Chemerin multifaceted actions, such as involvement in immune response, cell proliferation, and tissue remodeling, seem to be mediated by cytokines, at least in the endometrium. These findings underscore the potential crosstalk between chemerin and hormonal signaling pathways, providing insights into the complex mechanisms underlying early pregnancy establishment and maintenance.Graphical Abstract

It is well known that the body’s metabolism and reproduction are closely related. Chemerin (CHEM) is one of many biologically active proteins secreted by the adipose tissue involved in the regulation of the energy homeostasis of the organism. In the present study, RNA-sequencing was performed to investigate the differentially expressed genes (DEGs), long non-coding RNAs (lncRNAs), and alternatively spliced (AS) transcripts in the cultured porcine endometrium exposed to chemerin for 24 hours (CHEM; 400 ng/mL) collected during the implantation period (15–16 days of gestation). High-throughput sequencing of transcriptomes was performed on the Illumina NovaSeq 6000 platform (Illumina, USA). In the current study, among all 130 DEGs, 58 were upregulated and 72 were downregulated in the CHEM-treated group. DEGs were assigned to 73 functional annotations. Twelve identified lncRNAs indicated a difference in the expression profile after CHEM administration. Additionally, we detected 386 differentially AS events encompassed 274 protein-coding genes and 2 lncRNAs. All AS events were divided into five alternative splicing types: alternative 3′ splice site (A3SS), 5′ splice site (A5SS), mutually exclusive exons (MXE), retention intron (RI), and skipping exon (SE). Within all AS events, we identified 42 A3SS, 43 A5SS, 53 MXE, 9 RI, and 239 SE. In summary, CHEM affects the transcriptomic profile of the porcine endometrium, controlling the expression of numerous genes, including those involved in the cell migration and adhesion, angiogenesis, inflammation, and steroidogenesis. It can be assumed that CHEM may be an important factor for a proper course of gestation and embryo development.Chemerin takes part in the control of pig embryo implantation process via regulation of endometrial genes expression, including those involved in the cell migration and adhesion, angiogenesis, inflammation, and steroidogenesis.Graphical Abstract

The aim of this study was to evaluate the effect of prostaglandins E2(PGE2) and F2α(PGF2α) on orexins (OXA and OXB) secretion (ELISA), prepro-orexin (PPO) gene expression and the content of orexin receptors (OX1R, OX2R) mRNA (qPCR) and proteins (Western blot) in porcine endometrial and myometrial tissue slices during early pregnancy (days 10–28) and on days 10–11 of the oestrous cycle. On days 10–11 of pregnancy, prostaglandins (PGs) decreased the expression of the PPOgene and OXR gene and protein in the endometrium. On days 12– 13, PGs increased OXB secretion, PGE2enhanced OXA secretion, and PGF2αsuppressed PPOexpression. On days 15–16, both PGs inhibited PPOexpression and OXB secretion, and PGF2αincreased OXA release. On days 27–28, PGs decreased PPOmRNA and OX1R protein levels, PGE2decreased OX2R protein content, and PGF2αdecreased OXB secretion. On days 10-11 of the cycle PGs increased the expression of PPOmRNA and OX2R protein, whereas PGE2increased OX1R protein content. The effect of PGs on orexin system expression in the porcine myometrium was dependent on the animal physiological status and the concentrations of specific PGs. The study demonstrated that PGs exert regulatory effects on orexin system expression in the porcine uterus, which suggests that a local regulatory mechanism could be responsible for modulating uterine metabolism. The observed differences in PGs’ influence on orexin system expression could be attributed to changes in the sensitivity of the studied tissues, associated with the phase of the oestrous cycle, the stage of early pregnancy or PGs concentration.

The corpus luteum (CL) undergoes rapid changes, and its functional capabilities are influenced by processes such as angiogenesis and apoptosis. According to the literature, chemerin-a protein that participates in the regulation of energy homeostasis and the immune response, may also affect angiogenesis and apoptosis. Therefore, the aim of this study was to investigate the in vitro effect of chemerin on angiogenesis and apoptosis in porcine luteal cells (Lc) during specific phases related to CL physiology. Luteal cells were harvested from gilts during the early-, mid-, and late-luteal phases of the estrous cycle. The cells were preincubated for 48 h and incubated for 24 h with chemerin or a serum-free medium (controls). The abundance of angiogenesis- and apoptosis-related proteins was determined by enzyme-linked immunosorbent assay (ELISA) in spent culture media, or by ELISA and Western blot in protein extracts. The current study demonstrated that chemerin stimulates the production of vascular endothelial growth factor A (VEGF-A) and basic fibroblast growth factor (bFGF) by porcine Lc and increases the protein abundance of angiogenic factors’ receptors (VEGFR1, VEGFR2, VEGFR3, FGFR1, FGFR2) in these cells. The study also revealed that chemerin exerts a modulatory effect (stimulatory/inhibitory, depending on the phase of the cycle) on the protein abundance of first apoptosis signal (Fas), Fas ligand, B-cell lymphoma 2, and caspase-3 in porcine Lc. These results imply that chemerin may affect angiogenesis and apoptosis processes in the porcine CL, as evidenced by its modulatory effect of chemerin on the protein abundance of crucial angiogenesis- and apoptosis-related factors, observed in an in vitro study of porcine Lc.Chemerin may affect angiogenesis and apoptosis in the corpus luteum of pigs, as evidenced by the modulatory effect of this hormone on the protein abundance of angiogenesis- and apoptosis-related factors in the in vitro study of porcine luteal cells.

The aim of this study was to investigate the effect of orexin B (OXB) on progesterone (P4) and androstenedione (A4) secretion by porcine endometrial and myometrial tissue explants and on the expression of key steroidogenic proteins and enzymes involved in steroid production. The hormones secretion and the expression of steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage enzyme (CYP11A1), and 3β-hydroxysteroid dehydrogenase (HSD3B1) were analyzed on days 10 to 11, 12 to 13, 15 to 16, and 27 to 28 of pregnancy and during the luteal phase of the estrous cycle (days 10 to 11). Endometrial and myometrial explants were cultured in vitro in the presence of OXB (1, 10, or 100 nM) and OXB (1, 10, or 100 nM) with 1 µM of JNJ (OX2R antagonist). Gene expression was examined by real-time PCR, and steroid secretion was determined by radioimmunoassay. Orexin B modulated StAR, CYP11A1, HSD3B1 mRNA content depending on the type of uterine tissue, the applied OXB dose, and the stage of pregnancy or the estrous cycle (P < 0.05). Orexin B increased P4 secretion in all stages of early gestation (P < 0.05). Orexin B enhanced the release of A4 on days 12 to 13, 15 to 16, and 27 to 28 of gestation, whereas on days 10 to 11 of early pregnancy, A4 secretion decreased in the endometrium and increased in the myometrium (P < 0.05). These results indicate that OXB affects the expression of key steroidogenic regulators and the secretion of steroid hormones in the porcine uterus during early pregnancy.

Autophagy is indispensable for the proper architecture and flawless functioning of pancreatic β-cells. A growing body of evidence indicates reciprocal communication between autophagic pathways, apoptosis, and intracellular lipids. The way in which elevated levels of free saturated or unsaturated FAs contribute to progressive β-cell failure remains incompletely understood. Stearoyl-CoA desaturase (SCD)1, a key regulatory enzyme in biosynthesis of MUFAs, was shown to play an important role in regulation of β-cell function. Here, we investigated whether SCD1 activity is engaged in palmitate-induced pancreatic β-cell autophagy. We found augmented apoptosis and diminished autophagy upon cotreatment of INS-1E cells with palmitate and an SCD1 inhibitor. Furthermore, we found that additional treatment of the cells with monensin, an inhibitor of autophagy at the step of fusion, exacerbates palmitate-induced apoptosis. Accordingly, diminished SCD1 activity affected the accumulation, composition, and saturation status of cellular membrane phospholipids and neutral lipids. Such an effect was accompanied by aberrant endoplasmic reticulum stress, mitochondrial injury, and decreases in insulin secretion and cell proliferation. Our data reveal a novel mechanism by which the inhibition of SCD1 activity affects autophagosome-lysosome fusion because of perturbations in cellular membrane integrity, thus leading to an aberrant stress response and β-cell failure.

The heart of leptin-deficient ob/ob mice is characterized by pathologic left ventricular hypertrophy along with elevated triglyceride (TG) content, increased stearoyl-CoA desaturase (SCD) activity, and increased myocyte apoptosis. In the present study, using an ob/ob;SCD1–/–mouse model, we tested the hypothesis that lack of SCD1 could improve steatosis and left ventricle (LV) function in leptin deficiency. We show that disruption of the SCD1 gene improves cardiac function in ob/ob mice by correcting systolic and diastolic dysfunction without affecting levels of plasma TG and FFA. The improvement is associated with reduced expression of genes involved in FA transport and lipid synthesis in the heart, as well as reduction in cardiac FFA, diacylglycerol, TG, and ceramide levels. The rate of FA β-oxidation is also significantly lower in the heart of ob/ob;SCD1–/–mice compared with ob/ob controls. Moreover, SCD1 deficiency reduces cardiac apoptosis in ob/ob mice due to increased expression of antiapoptotic factor Bcl-2 and inhibition of inducible nitric oxide synthase and caspase-3 activities. Reduction in myocardial lipid accumulation and inhibition of apoptosis appear to be one of the main mechanisms responsible for improved LV function in ob/ob mice caused by SCD1 deficiency.

Stearoyl-CoA desaturase 1 (SCD1) has been implicated as a novel therapeutic target for the treatment of a variety of metabolic diseases, including diabetes, obesity, hepatic steatosis, atherosclerosis and cardiovascular disease. The application WO2009129625 from Merck Frosst Canada claims novel substituted heteroaromatic compounds as inhibitors of SCD and potential drugs for the pharmacological treatment of metabolic disorders, when used alone or in combination with other drugs. Based on in vitroactivity of the patented compounds, these molecules may be considered as potential SCD inhibitors and could be of therapeutic value. However, further preclinical studies are needed to evaluate their curative potential and safety before clinical development.

Stearoyl-CoA desaturase (SCD) is a central enzyme responsible for the synthesis of mono-unsaturated fatty acids, mainly oleate (C18:1), a major component of tissue lipids. Recent studies have revealed that mice deficient in SCD1 have reduced tissue lipid accumulation and increased insulin sensitivity, and are resistant to diet- and leptin-deficiency-induced obesity. These facts demonstrate that SCD activity/gene expression inhibition may be a potential therapeutic target in the prevention of diabetes and the metabolic syndrome. This patent describes novel cyclic amine derivatives that inhibit SCD activity in liver and potentially may be used in combination with other drugs (e.g., PPARγ agonists, insulin or insulin mimetics, glucagon receptor antagonists, glucokinase activators). Based on their in vitroactivity, it is probable that these compounds could be of therapeutic value for the treatment of disorders connected with obesity, but more experimental and clinical studies need to be done to validate these novel SCD inhibitors.

Stearoyl‐CoA desaturase (SCD) is the rate limiting enzyme catalyzing the biosynthesis of monounsaturated fatty acids, mainly oleate and palmitoleoate, which are used as substrates for the synthesis of triglycerides, wax esters, cholesterol esters, and phospholipids. Recent studies have shown that SCD1, the main SCD isoform expressed in liver, is a key player in the regulation of lipid metabolism. SCD1 deficient mice have increased energy expenditure, reduced body adiposity, increased insulin sensitivity and are resistant to diet‐induced obesity and liver steatosis. SCD1 was found to be specifically repressed during leptin‐mediated weight loss and leptin‐deficient ob/obmice lacking SCD1 showed markedly reduced adiposity, despite higher food intake. In addition, SCD1 deficiency completely corrects the hypometabolic phenotype and hepatic steatosis of ob/obmice, and attenuates fasting‐induced liver steatosis in peroxisome proliferator‐activated receptor‐α – deficient mice. Consequently, increased SCD activity has been found in humans and animals which accumulate significant amounts of lipids in liver, whereas SCD1 deficiency ameliorates both high‐fat diet induced and genetically induced hepatic steatosis. Much evidence indicates that the direct anti‐steatotic effect of SCD1 deficiency stems from increased fatty acid oxidation and reduced lipid synthesis. In this review we discuss our current understanding of the role of SCD1 in regulation of hepatic lipid partitioning and test the hypothesis that pharmacological manipulation of SCD might be of benefit in the treatment of non‐alcoholic fatty liver disease. Drug Dev. Res. 67:643–650, 2006. © 2006 Wiley‐Liss, Inc.

Stearoyl-CoA desaturase (SCD) is a microsomal enzyme involved in the biosynthesis of oleate and palmitoleate. Mice with a targeted disruption of the SCD1 isoform (SCD1-/-) exhibit reduced adiposity and increased energy expenditure. To address whether the energy expenditure is attributable to increased thermogenesis, we investigated the effect of SCD1 deficiency on basal and cold-induced thermogenesis. SCD1-/- mice have increased expression of uncoupling proteins in brown adipose tissue (BAT) relative to controls. The beta3-adrenergic receptor (beta3-AR) expression was increased and the phosphorylation of cAMP response element binding protein and the protein level of peroxisome proliferator-activated receptor-gamma coactivator-1alpha were increased in the SCD1-/- mice. Both lipolysis and fatty acid oxidation were increased in the SCD1-/- mice. When exposed to 4 degrees C, SCD1-/- mice showed hypothermia, hypoglycemia, and depleted liver glycogen. High levels of dietary oleate partially compensated for the hypothermia and rescued plasma glucose and liver glycogen. These results suggest that SCD1 deficiency stimulates basal thermogenesis through the upregulation of the beta3-AR-mediated pathway and a subsequent increase in lipolysis and fatty acid oxidation in BAT. The hypothermia and hypoglycemia in cold-exposed SCD1-/- mice and the compensatory recovery by oleate indicate an important role of SCD1 gene expression in thermoregulation.

The aim of this study was to investigate the influence of progesterone (P4) on adiponectin system genes and protein expression in the endometrium and myometrium during early gestation. Twenty-five gilts were assigned to 1 of 5 groups (n= 5): d 10 to 11 (embryo migration), 12 to 13 (maternal recognition of pregnancy), 15 to 16 (implantation), and 27 to 28 (end of implantation) of pregnancy and d 10 to 11 of the cycle (fully active corpora lutea, corresponding to the corpora lutea activity during gestation). The endometrial and myometrial tissues were cut into 100 mg slices, treated with P4 (10, 100, 1000 nM) and incubated for 24 h. Gene expression was analyzed by the real-time PCR method. Adiponectin secretion was determined by ELISA. Receptor protein content was defined using Western Blot analysis. In the endometrium, on d 10 to 11 of pregnancy, P4 stimulated adiponectin protein secretion. On those days, P4 enhanced adiponectin receptor type 1 (AdipoR1) and type 2 (AdipoR2) gene expression but inhibited both receptors' protein content. On d 12 to 13 of pregnancy, P4 inhibited adiponectin gene expression. During those period, P4 enhanced AdipoR1gene expression but suppressed both receptors' protein content. On d 15 to 16 of gestation, P4 increased adiponectin gene expression but inhibited the protein secretion. During those days, P4 suppressed AdipoR1gene expression and enhanced AdipoR2 protein content. On d 27 to 28 of gestation, P4 enhanced AdipoR2gene and AdipoR1 protein expression (P< 0.05). In the myometrium, on d 10 to 11 of gestation, P4 increased both receptors' gene expression but suppressed their protein content. On d 12 to 13 of pregnancy, P4 increased adiponectin and AdipoR1genes and AdipoR1 protein expression but decreased AdipoR2 protein content. On d 15 to 16 of gestation, P4 inhibited adiponectin gene expression. On those days, P4 enhanced AdipoR2gene and protein expression. On d 27 to 28 of gestation, P4 decreased adiponectin gene expression. On those days, P4 increased the myometrial AdipoR2 protein concentration and decreased AdipoR1gene protein expression (P< 0.05). Overall, the influence of P4 was found to be tissue specific and dose dependent. Results presented in this study indicate the modulatory effect of P4 on adiponectin system in the porcine uterus during early pregnancy, which may suggest the involvement of this adipokine in the early pregnancy establishment.

The Effect Occupational Exposure to Ionizing Radiation on the DNA Damage in Peripheral Blood Leukocytes of Nuclear Medicine Personnel: Małgorzata M. DOBRZYŃSKA, et al. Department of Radiation Hygiene and Radiobiology, National Institute of Public Health – National Institute of Hygiene, Poland— The aim of this study was estimation of DNA strand breaks in leukocytes of peripheral blood of staff in a nuclear medicine department. The exposed group consisted of 46 volunteers and the control group consisted of 40 volunteers. Samples consisting of 1 ml whole blood were collected by venepuncture. DNA damage in leukocytes was detected by alkaline comet assay. There was no correlation between the effective dose measured by individual dosimeters and DNA damage and no differences between sexes. The mean level of damage to DNA in people exposed to ionizing radiation was significantly elevated compared with control individuals. The highest value for mean comet tail moment was noted in leukocytes of PET/CT and scintigraphy technicians (1.28 vs. 0.30 for control, p=0.013). The levels of DNA damage in leukocytes of workers in category B (effective dose may exceed 1 mSv/year) were significantly enhanced. The DNA migration of leukocytes in exposed smokers and nonsmokers was similar. In the control group the damage to DNA of leukocytes in smokers was markedly but not significantly higher compared with nonsmokers. Occupational exposure to ionizing radiation leads to enhanced levels of reversible DNA damage in leukocytes of nuclear medicine employees. The level of DNA damage depends on the kind of work. Cigarette smoking is related to the increase in DNA damage in unexposed individuals but not in nuclear medicine workers. Radiation seems to be a stronger inducer of DNA damage than smoking. Although most of the DNA damage detected by comet assay is repaired, further improvement of radiation safety should be taken under consideration.

Despite positive effects on the plasma lipid profile and vascular events, statin use is associated with various side effects. Among these, statins might cause a disruption of a number of regulatory pathways including insulin signaling. This may affect insulin sensitivity, pancreatic beta-cell function and adipokine secretion. The statin-associated risk of new-onset diabetes (NOD) appears to be a dose-dependent class effect. It still remains unclear whether statin treatment is associated with increased risk of NOD in the general population or if there are groups of individuals at particular risk. However, according to the available data it seems that cardiovascular (CV) benefits in high-risk individuals strongly favor statin therapy since it outweighs other risks. Whether statins should be used for primary prevention among patients with a relatively low baseline CV risk is still questionable, however the results of primary prevention trials have shown reductions in mortality in this population. Thus, there is a need for randomized, placebo-controlled statin studies with carefully selected groups of patients and NOD as a key end point in order to resolve queries concerning this issue.

Maskin is the Xenopushomolog of the transforming acidic coiled coil (TACC)-family of microtubule and centrosome-interacting proteins. Members of this family share a ∼200 amino acid coiled coil motif at their C-termini, but have only limited homology outside of this domain. In all species examined thus far, perturbations of TACC proteins lead to disruptions of cell cycle progression and/or embryonic lethality. In Drosophila, Caenorhabditis elegans, and humans, these disruptions have been attributed to mitotic spindle assembly defects, and the TACC proteins in these organisms are thought to function as structural components of the spindle. In contrast, cell division failure in early Xenopusembryo blastomeres has been attributed to a role of maskin in regulating the translation of, among others, cyclin B1 mRNA. In this study, we show that maskin, like other TACC proteins, plays a direct role in mitotic spindle assembly in Xenopusegg extracts and that this role is independent of cyclin B. Maskin immunodepletion and add-back experiments demonstrate that maskin, or a maskin-associated activity, is required for two distinct steps during spindle assembly in Xenopusegg extracts that can be distinguished by their response to “rescue” experiments. Defects in the “early” step, manifested by greatly reduced aster size during early time points in maskin-depleted extracts, can be rescued by readdition of purified full-length maskin. Moreover, defects in this step can also be rescued by addition of only the TACC-domain of maskin. In contrast, defects in the “late” step during spindle assembly, manifested by abnormal spindles at later time points, cannot be rescued by readdition of maskin. We show that maskin interacts with a number of proteins in egg extracts, including XMAP215, a known modulator of microtubule dynamics, and CPEB, a protein that is involved in translational regulation of important cell cycle regulators. Maskin depletion from egg extracts results in compromised microtubule asters and spindles and the mislocalization of XMAP215, but CPEB localization is unaffected. Together, these data suggest that in addition to its previously reported role as a translational regulator, maskin is also important for mitotic spindle assembly.

Sphingomyelin has been shown to be a source of bioactive compounds. This sphingolipid is located mostly in the outer layer of the plasma membrane and in the membranes of organelles. Sphingomyelin located in the plasma membrane is hydrolyzed into ceramide and phosphorylcholine. Ceramide is the principal second messenger in the sphingomyelin transmembrane signaling pathway. Products of ceramide metabolism, namely, sphingosine, sphingosine-1-phosphate, and ceramide-1-phosphate, also exert broad biological effects. The major effects of ceramide are induction of differentiation, inhibition of proliferation, regulation of inflammatory processes, and induction of apoptosis. There is also convincing evidence that ceramide counteracts insulin-stimulated glucose uptake. Ceramides are also present in skeletal muscles. We investigated ceramide metabolism in different skeletal muscle types of the rat at rest and after prolonged exercise of moderate intensity. Exercise reduced the total content of ceramide fatty acids and changed their composition in each muscle type. These data indicate that the sphingomyelin-signaling pathway functions in skeletal muscles and that its activity is downregulated during prolonged exercise. The content of ceramide in the muscles was inversely related to 2-deoxyglucose uptake by the muscles. This indicates that ceramide may be involved in regulation of glucose uptake by skeletal muscles in vivo.

The kinetic behavior of pig heart pyruvate dehydrogenase complex (PDC) containing bound endogenous thiamin pyrophosphate (TPP) was affected by exogenous TPP. In the absence of exogenous TPP, a lag phase of the PDC reaction was observed. TPP added to the PDC reaction medium containing Mg2+led to a disappearance of the lag phase, inducing strong reduction of theKmvalue for pyruvate (from 76.7 to 19.0 μM) but a more moderate decrease ofKmfor CoA (from 12.2 to 4.3 μM) andKmfor NAD+(from 70.2 to 33.6 μM), with no considerable change in the maximum reaction rate. Likewise, thiamin monophosphate (TMP) decreased theKmvalue of PDC for pyruvate, but to a lesser extent (from 76.7 to 57.9 μM) than TPP. At the unsaturating level of pyruvate, theA50values for TPP and TMP were 0.2 μM and 0.3 mM, respectively. This could mean that the effect of TPP on PDC was more specific. In addition, exogenous TPP changed the UV spectrum and lowered the fluorescence emission of the PDC containing bound endogenous TPP in its active sites. The data obtained suggest that TPP plays, in addition to its catalytic function, the important role of positive regulatory effector of pig heart PDC.

The properties of amorphous ribbons of (Co 0.93−y Ni y Fe 0.07 ) 75 Si 15 B 10 with y up to 0.93 are described. particular attention is paid to the magnetization and hyperfine-field distribution. It is shown that the magnetic moment per cobalt atom is 1.07(3)μ B , while the magnetic moment of iron is estimated to be 1.73(3)μ B . Except of the high nickel concentration region a weak magnetic moment, 0.12(5)μ B , is present on nickel atoms. For y > 0.64 a transition to the spin-glass-like state is observed. The exchange stiffness constants, as measured through the temperature dependence of the magnetization, vary linearly with the Curie temperature. It is concluded from the data that with increasing nickel content the effective exchange interaction decreases exponentially with the average distance between interacting atoms.