Randomized assessment of imatinib in patients with acute ischaemic stroke treated with intravenous thrombolysis.

BACKGROUND: Imatinib, a tyrosine kinase inhibitor, has been shown to restore blood-brain barrier integrity and reduce infarct size, haemorrhagic transformation and cerebral oedema in stroke models treated with tissue plasminogen activator. We evaluated the safety of imatinib, based on clinical and neuroradiological data, and its potential influence on neurological and functional outcomes. METHODS: A phase II randomized trial was performed in patients with acute ischaemic stroke treated with intravenous thrombolysis. A total of 60 patients were randomly assigned to four groups [3 (active): 1 (control)]; the active treatment groups received oral imatinib for 6 days at three dose levels (400, 600 and 800 mg). Primary outcome was any adverse event; secondary outcomes were haemorrhagic transformation, cerebral oedema, neurological severity on the National Institutes of Health Stroke Scale (NIHSS) at 7 days and at 3 months and functional outcomes on the modified Rankin scale (mRS). RESULTS: Four serious adverse events were reported, which resulted in three deaths (one in the control group and two in the 400-mg dose group; one patient in the latter group did not receive active treatment and the other received two doses). Nonserious adverse events were mostly mild, resulting in full recovery. Imatinib ameliorated neurological outcomes with an improvement of 0.6 NIHSS points per 100 mg imatinib (P = 0.02). For the 800-mg group, the mean unadjusted and adjusted NIHSS improvements were 4 (P = 0.037) and 5 points (P = 0.012), respectively, versus controls. Functional independence (mRS 0-2) increased by 18% versus controls (61 vs. 79; P = 0.296). CONCLUSION: This phase II study showed that imatinib is safe and tolerable and may reduce neurological disability in patients treated with intravenous thrombolysis after ischaemic stroke. A confirmatory randomized trial is currently underway.

Bangladeshi school-age children's experiences and perceptions on child maltreatment: A qualitative interview study.

BACKGROUND: Child maltreatment (CM) is a public health problem and is recognized as a huge barrier for child development. Most of the research and definitions on CM are from the perspective of high-income western countries. Because no major studies have been conducted on CM in Bangladesh, the aim of the current study was to explore the experiences of and perceptions on CM in school-age children in rural and urban Bangladesh in order to understand maltreatment in a local context and from a child perspective. METHODS: Semistructured individual interviews with 24 children (13 boys and 11 girls), between the ages of 9 and 13 years of which 11 were schoolgoing and 13 non-schoolgoing, were conducted during July 2013 and analysed according to qualitative content analysis. RESULTS: CM was a common and painful experience with serious physical and emotional consequences but highly accepted by the society. Vulnerable groups were especially young children, girls, and poor children. The children's voices were not heard due to their low status and low position in their families, schools, and working places. The main theme that emerged in the analysis was children's subordination, which permeated the five categories: (a) perception of children's situation in society, (b) understanding children's development and needs, (c) CM associated to school achievement, (d) negative impact of CM, and (e) emotional responses. CONCLUSIONS: Different kinds of abuse are obviously common in Bangladesh, and the schools do not follow the law from 2011 prohibiting corporal punishment at school. The society has to take further steps to live up to the UN Convention on the Rights of the Child, which was ratified already in 1990, to protect the Bangladeshi children from CM.

Exploring risk for abuse of children with chronic conditions or disabilities--parent's perceptions of stressors and the role of professionals.

BACKGROUND: Children with chronic conditions or disabilities are at an increased risk for abuse. High level of parental stress has been identified as possible trigger for abuse, were a combination of several factors are of importance, as lack of social support and limited resources in the neighbourhood. Suggestions for preventive measures have merely focused on parenting strategies and targeted intervention programmes. So far, little attention has been paid on how the risk for abuse might relate to parent's perceptions of stressors and the role of professionals. The purpose of the current study was therefore to explore risk factors for abuse with focus on both parent-child and parent-professional relationships. METHOD: Semi-structured in-depth interviews with 15 parents of children with chronic conditions or disability were collected and analysed according to qualitative content analysis. FINDINGS: Three major themes were found that could be seen as risk factors for child abuse: (1) Emotional demands in precarious situations between parent and child. (2) Gradual shift in responsibility from professionals to parents concerning access to and co-ordination of service and support. (3) Emotionally closed environment between professionals and parents and taboo on talking about abuse. The gradual shift in responsibility had emotional implications, which could reinforce parental stress and thereby also indirect increase the risk of child abuse. The gradual shift in responsibility also seemed to generate an emotionally closed environment and reinforce the taboo on talking about abuse, which in turn hindered preventive measures. CONCLUSIONS: In the light of parent's perceptions of stressors and the role of professionals the findings indicate that abuse against children with chronic conditions or disability is not only a family matter, but also depending on qualities in service, professional support and social norms. The result pinpoints three challenges for preventive measures, all with emotional implications, parental strategies, organizational efforts and cultural awareness.

Mutations in the gene encoding 11-cis retinol dehydrogenase cause delayed dark adaptation and fundus albipunctatus.

The metabolic pathways that produce 11-cis retinal are important for vision because this retinoid is the chromophore residing in rhodopsin and the cone opsins. The all-trans retinal that is generated after cone and rod photopigments absorb photons of light is recycled back to 11-cis retinal by the retinal pigment epithelium and Müller cells of the retina. Several of the enzymes involved have recently been purified and molecularly cloned; here we focus on 11-cis retinol dehydrogenase (encoded by the gene RDH5; chromosome 12q13-14; ref. 4), the first cloned enzyme in this pathway. This microsomal enzyme is abundant in the retinal pigment epithelium, where it has been proposed to catalyse the conversion of 11-cis retinol to 11-cis retinal. We evaluated patients with hereditary retinal diseases featuring subretinal spots (retinitis punctata albescens and fundus albipunctatus) and patients with typical dominant or recessive retinitis pigmentosa for mutations in RDH5. Mutations were found only in two unrelated patients, both with fundus albipunctatus; they segregated with disease in the respective families. Recombinant mutant 11-cis retinol dehydrogenases had reduced activity compared with recombinant enzyme with wild-type sequence. Our results suggest that mutant alleles in RDH5 are a cause of fundus albipunctatus, a rare form of stationary night blindness characterized by a delay in the regeneration of cone and rod photopigments.

The influence of genetic variation on innate immune activation in an environment with high infectious pressure.

Interleukin-10 (IL-10) production is under tight genetic control in populations living in affluent environments. However, little is known about the role of IL10 genetics on cytokine production in populations living in environments with high infectious pressure. We have previously reported that, in a rural Ghanaian population, the most common IL10 haplotype associates with a pro-inflammatory response. Here, we aim to replicate these findings in an independent sample of the same population 2 years later. IL-10 and tumour necrosis factor-α (TNF-α) protein concentrations were determined in whole-blood samples ex vivo stimulated with lipopolysaccharide and zymosan in 2006 (n=615) and 2008 (n=647). The association between IL10 single nucleotide polymorphisms and Z-scores of IL-10 and TNF-α levels was analysed in each population subset. The most common IL10 haplotype was associated with a significantly lower IL-10 production and nonsignificantly increased TNF-α levels. The correlation between repeated cytokine assays, based on 111 individuals with measurements in both 2006 and 2008, was r=0.53 (P<0.001) for IL-10 and r=0.36 (P<0.001) for TNF-α. The replication of our previously found effect of variation in the IL10 gene on IL-10 production and the correlation between repeated cytokine stimulation assays provide evidence that IL10 genetics have an important role in regulating the host response under high infectious pressure.

Influence of maternal metabolism and parental genetics on fetal maldevelopment in diabetic rat pregnancy.

The purpose of this study was to investigate the influence of parental transgenerational genetics and maternal metabolic state on fetal maldevelopment in diabetic rat pregnancy. Rats from an inbred malformation-resistant (W) strain, and an inbred malformation-prone (L) strain, were cross-mated to produce two different F(1) hybrids, WL and LW. Normal (N) and manifestly diabetic (MD) WL and LW females were mated with normal males of the same F(1) generation to obtain WLWL and LWLW F(2) hybrids. Maternal diabetes increased malformation and resorption rates in both F(2) generations. MD-WLWL offspring had higher resorption rate but similar malformation rate compared with the MD-LWLW offspring. Malformed MD-WLWL offspring presented with 100% agnathia/micrognathia, whereas malformed MD-LWL offspring had 60% agnathia/micrognathia and 40% cleft lip and palate. The MD-WL dams showed increased ß-hydroxybutyrate levels and alterations in concentrations of several amino acids (taurine, asparagine, citrulline, cystine, glutamic acid, leucine, tyrosine, and tryptophan) compared with MD-LW dams. Fetal glyceraldehyde-3-phosphate dehydrogenase (Gapdh) activity and gene expression were more altered in MD-WLWL than MD-LWLW. Fetal gene expression of reactive oxygen species (ROS) scavenger enzymes was diminished in MD-WLWL compared with MD-LWLW. Glial cell line-derived neurotrophic factor and Ret proto-oncogene gene expression was decreased in both MD-WLWL and MD-LWLW fetuses, whereas increased bone morphogenetic protein 4 and decreased Sonic hedgehog homolog expression was found only in MD-LWLW fetuses. Despite identical autosomal genotypes, the WL and LW dams gave birth to offspring with markedly different malformation patterns. Together with fetal differences in enzymatic activity and expression of Gapdh, ROS scavengers, and developmental genes, these results may suggest a teratological mechanism in diabetic pregnancy influenced by maternal metabolism and parental strain epigenetics.

Genetic and environmental influence on diabetic rat embryopathy.

We assessed genetic and environmental influence on fetal outcome in diabetic rat pregnancy. Crossing normal (N) and manifestly diabetic (MD) Wistar Furth (W) and Sprague-Dawley (L) females with W or L males yielded four different fetal genotypes (WW, LL, WL, and LW) in N or MD rat pregnancies for studies. We also evaluated fetal outcome in litters with enhanced or diminished severity of maternal MD state, denoted MD(+)WL and MD(-)LW. The MDWW litters had less malformations and resorptions (0 and 19%) than the MDLL litters (17 and 30%). The MDWL litters (0 and 8%) were less maldeveloped than the MDLW litters (9 and 22%), whereas the MD(+)WL (3 and 23%) and MD(-)LW (1 and 17%) litters showed increased and decreased dysmorphogenesis (compared with MDWL and MDLW litters). The pregnant MDW rats had lower serum levels of glucose, fructosamine, and branched-chain amino acids than the pregnant MDL rats, whereas the pregnant MD(+)W and MD(-)L rats had levels comparable with those of the MDL and MDW rats, respectively. The 8-iso-PGF2α levels of the malformed MDLW offspring were increased compared with the nonmalformed MDLW offspring. Diabetes decreased fetal heart Ret and increased Bmp-4 gene expression in the MDLW offspring and caused decreased GDNF and Shh expression in the malformed fetal mandible of the MDLW offspring. We conclude that the fetal genome controls the embryonic dysmorphogenesis in diabetic pregnancy by instigating a threshold level for the teratological insult and that the maternal genome controls the teratogenic insult by (dys)regulating the maternal metabolism.

PDGF-D is a specific, protease-activated ligand for the PDGF beta-receptor.

The term 'platelet-derived growth factor' (PDGF) refers to a family of disulphide-bonded dimeric isoforms that are important for growth, survival and function in several types of connective tissue cell. So far, three different PDGF chains have been identified - the classical PDGF-A and PDGF-B and the recently identified PDGF-C. PDGF isoforms (PDGF-AA, AB, BB and CC) exert their cellular effects by differential binding to two receptor tyrosine kinases. The PDGF alpha-receptor (PDGFR-alpha) binds to all three PDGF chains, whereas the beta-receptor (PDGFR-beta) binds only to PDGF-B. Gene-targeting studies using mice have shown that the genes for PDGF-A and PDGF-B, as well as the two PDGFR genes, are essential for normal development. Furthermore, overexpression of PDGFs is linked to different pathological conditions, including malignancies, atherosclerosis and fibroproliferative diseases. Here we have identify and characterize a fourth member of the PDGF family, PDGF-D. PDGF-D has a two-domain structure similar to PDGF-C and is secreted as a disulphide-linked homodimer, PDGF-DD. Upon limited proteolysis, PDGF-DD is activated and becomes a specific agonistic ligand for PDGFR-beta. PDGF-DD is the first known PDGFR-beta-specific ligand, and its unique receptor specificity indicates that it may be important for development and pathophysiology in several organs.

PDGF-C is a new protease-activated ligand for the PDGF alpha-receptor.

Platelet-derived growth factors (PDGFs) are important in many types of mesenchymal cell. Here we identify a new PDGF, PDGF-C, which binds to and activates the PDGF alpha-receptor. PDGF-C is activated by proteolysis and induces proliferation of fibroblasts when overexpressed in transgenic mice. In situ hybridization analysis in the murine embryonic kidney shows preferential expression of PDGF-C messenger RNA in the metanephric mesenchyme during epithelial conversion. Analysis of kidneys lacking the PDGF alpha-receptor shows selective loss of mesenchymal cells adjacent to sites of expression of PDGF-C mRNA; this is not found in kidneys from animals lacking PDGF-A or both PDGF-A and PDGF-B, indicating that PDGF-C may have a unique function.

Synergism between vascular endothelial growth factor and placental growth factor contributes to angiogenesis and plasma extravasation in pathological conditions.

Vascular endothelial growth factor (VEGF) stimulates angiogenesis by activating VEGF receptor-2 (VEGFR-2). The role of its homolog, placental growth factor (PlGF), remains unknown. Both VEGF and PlGF bind to VEGF receptor-1 (VEGFR-1), but it is unknown whether VEGFR-1, which exists as a soluble or a membrane-bound type, is an inert decoy or a signaling receptor for PlGF during angiogenesis. Here, we report that embryonic angiogenesis in mice was not affected by deficiency of PlGF (Pgf-/-). VEGF-B, another ligand of VEGFR-1, did not rescue development in Pgf-/- mice. However, loss of PlGF impaired angiogenesis, plasma extravasation and collateral growth during ischemia, inflammation, wound healing and cancer. Transplantation of wild-type bone marrow rescued the impaired angiogenesis and collateral growth in Pgf-/- mice, indicating that PlGF might have contributed to vessel growth in the adult by mobilizing bone-marrow-derived cells. The synergism between PlGF and VEGF was specific, as PlGF deficiency impaired the response to VEGF, but not to bFGF or histamine. VEGFR-1 was activated by PlGF, given that anti-VEGFR-1 antibodies and a Src-kinase inhibitor blocked the endothelial response to PlGF or VEGF/PlGF. By upregulating PlGF and the signaling subtype of VEGFR-1, endothelial cells amplify their responsiveness to VEGF during the 'angiogenic switch' in many pathological disorders.

Single-dose pharmacokinetics, pharmacodynamics and safety of AZD0837, a novel oral direct thrombin inhibitor, in young healthy male subjects.

OBJECTIVE: The novel oral anticoagulant AZD0837 is currently in clinical development for the prevention of stroke and systemic embolic events in patients with atrial fibrillation. AZD0837 is bioconverted to AR-H067637, a selective and reversible direct thrombin inhibitor. This first-time-in-man study (study code D1250C00001) investigated the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of AZD0837. METHODS: Healthy Caucasian male volunteers (n = 44, age 20 - 39 y) were enrolled into this study of single oral escalating doses of AZD0837 given in solution (15 - 750 mg, n = 4 per dose). PD was assessed by ex vivo measurements of activated partial thromboplastin time (APTT), ecarin coagulation time (ECT), thrombin time (TT) and thrombin generation in plasma. RESULTS: AZD0837 was rapidly absorbed, with a mean oral bioavailability of 22 - 52%, and bioconverted to the active form, AR-H067637. In fasting subjects, maximum plasma concentrations (Cmax) for AR-H067637 occurred approximately 1 h post-dosing and declined with a mean half-life of 9.3 h. The Cmax and area under the curve for AR-H067637 showed a low to moderate inter-individual variability of 16% and 28%, respectively, and exhibited a slight deviation from dose-proportionality. AZD0837 produced a dose-dependent prolongation of APTT, ECT and TT, and decreased maximum free thrombin activity. AZD0837 was generally well tolerated. CONCLUSIONS: AZD0837 single oral doses (15 - 750 mg) are well tolerated in healthy male subjects and exhibit favorable PK properties and reproducible effects on ex vivo coagulation time variables that support further clinical development.

PDGF-C and -D and their receptors PDGFR-alpha and PDGFR-beta in atherosclerotic human arteries.

BACKGROUND: Platelet derived growth factors (PDGFs) are mitogens for fibroblasts and smooth muscle cells. This growth factor family contains four members PDGF-A, PDGF-B, PDGF-C and PDGF-D. Biology of recently discovered PDGF-C and PDGF-D is not well-established. Here we studied the expression of PDGF-C and PDGF-D and their receptors PDGFR-alpha and PDGFR-beta in normal and atherosclerotic human arteries. MATERIALS AND METHODS: Human arterial samples from amputations and autopsies were classified according to the atherosclerotic stage and the expression of PDGF-C and PDGF-D proteins and their receptors was studied by immunohistochemistry. In situ hybridization and reverse transcriptase-PCR were used to study mRNA expression. RESULTS: Both growth factors were expressed in medial smooth muscle cells (SMCs) in normal arteries and atherosclerotic lesions. However, clear differences were found in the expression profiles in endothelium: PDGF-C was strongly expressed in endothelial cells in both normal arteries and lesions whereas PDGF-D was only weakly expressed in endothelium. PDGF-C expression was very prominent in lesion macrophages. PDGF-D was expressed throughout the artery wall in lesions. PDGFR-alpha expression was strong in endothelium and in lesion macrophage-rich areas, whereas PDGFR-beta was mostly expressed in SMCs. CONCLUSIONS: Our results suggest that PDGF-C may play an important role in endothelium in normal and atherosclerotic arteries and in macrophages in lesions. PDGF-D was expressed in all types of lesions with the same intensity and thus differs from the expression of PDGF-C.

Lack of pericytes leads to endothelial hyperplasia and abnormal vascular morphogenesis.

The association of pericytes (PCs) to newly formed blood vessels has been suggested to regulate endothelial cell (EC) proliferation, survival, migration, differentiation, and vascular branching. Here, we addressed these issues using PDGF-B-- and PDGF receptor-beta (PDGFR-beta)--deficient mice as in vivo models of brain angiogenesis in the absence of PCs. Quantitative morphological analysis showed that these mutants have normal microvessel density, length, and number of branch points. However, absence of PCs correlates with endothelial hyperplasia, increased capillary diameter, abnormal EC shape and ultrastructure, changed cellular distribution of certain junctional proteins, and morphological signs of increased transendothelial permeability. Brain endothelial hyperplasia was observed already at embryonic day (E) 11.5 and persisted throughout development. From E 13.5, vascular endothelial growth factor-A (VEGF-A) and other genes responsive to metabolic stress became upregulated, suggesting that the abnormal microvessel architecture has systemic metabolic consequences. VEGF-A upregulation correlated temporally with the occurrence of vascular abnormalities in the placenta and dilation of the heart. Thus, although PC deficiency appears to have direct effects on EC number before E 13.5, the subsequent increased VEGF-A levels may further abrogate microvessel architecture, promote vascular permeability, and contribute to formation of the edematous phenotype observed in late gestation PDGF-B and PDGFR-beta knock out embryos.

Altered uterine perfusion is involved in fetal outcome of diabetic rats.

Maternal diabetes affects the development of the offspring by altering the uterine environment. We aimed to investigate the extent to which the blood flow (measured as Tissue Perfusion Units; TPU) to implantation sites and the expression of developmentally important genes in the offspring are affected by maternal diabetes. We measured mRNA levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), Bcl-2 associated X protein (Bax), B-cell lymphoma protein (Bcl-2), tumor suppressor protein-53 (p53), paired box protein-3 (Pax-3) and vascular endothelial growth factor-A (Vegf-A). Moreover, we studied the effect on uterine blood flow (TPU) and the expression of the genes exerted by embryonic maldevelopment (malformation or resorption). Streptozotocin induced diabetic (D) and non-diabetic (N) pregnant rats were used in the study. Blood flow (TPU) to implantation sites was measured by a laser Doppler flow meter, and gene expression was analyzed by RT-PCR. Maternal diabetes caused increased blood flow (TPU) to implantation sites compared with normal pregnancy. Furthermore, implantation sites of D rats containing malformed offspring showed impaired growth and decreased blood flow (TPU) compared with their littermates at all gestational days. Resorbed offspring from both N and D rats displayed increased blood flow (TPU) compared with their non-resorbed littermates. Moreover, we found that maternal diabetes causes decreased expression of genes involved in the oxidative stress defense system (CuZnSOD in non-malformed D11 embryos, MnSOD at all gestational time points, ECSOD and Gpx-1 at GD11-GD15, CAT and Gpx-2 at GD15), decreased expression of Pax-3 at GD11, and increased expression of Vegf-A at all gestational time points. We conclude that both maternal metabolism and embryonic developmental state affect the blood flow (TPU) to the implantation site. Maternal diabetes causes decreased expression of anti-oxidative enzymes and enhanced angiogenesis in the offspring in rats.

[28-year old patient with successfully treated dilatative cardiomyopathy]. / 28-jähriger Patient mit erfolgreich behandelter dilatativer Kardiomyopathie.

A 28-year was admitted with heart failure. His medical history included treatment for hypogonadotropic hypogonadism. Echocardiography showed dilatation of all chambers. Elevated serum ferritin levels and liver biopsy indicated hereditary hemochromatosis. Cardiac iron overload was seen on magnetic resonance imaging. Genetic testing revealed homozygosis for G320 V mutation, confirming the diagnosis of juvenile hemochromatosis. Phlebotomy on a biweekly regimen was started and after twelve months of therapy the patient had normal ferritin values as well as normal ejection fraction on echocardiography.

Neurological and neuropsychological effects of low and moderate prenatal alcohol exposure.

Several explanations for the diverse results in research on foetal alcohol spectrum disorders or alcohol-related neurodevelopmental disorder might be at hand: timing, amount and patterns of alcohol exposure, as well as complex epigenetic responses. The genetic background of the offspring and its interaction with other prenatal and post-natal environmental cues are likely also of importance. In the present report, key findings about the possible effects of low and moderate doses of maternal alcohol intake on the neuropsychological development of the offspring are reviewed and plausible mechanisms discussed. Special focus is put on the serotonergic system within developmental and gene-environment frameworks. The review also suggests guidelines for future studies and also summarizes some of to-be-answered questions of relevance to clinical practice. Contradictory findings and paucity of studies on the effects of exposure to low alcohol levels during foetal life for the offspring's neuropsychological development call for large prospective studies, as well as for studies including neuroimaging and multi-omics analyses to dissect the neurobiological underpinnings of alcohol exposure-related phenotypes and to identify biomarkers. Finally, it remains to be investigated whether any safe threshold of alcohol drinking during pregnancy can be identified.

Suramin-restricted blood volume in the placenta of normal and diabetic rats is normalized by vitamin E treatment.

Previously maternal and fetal alterations resembling human pre-eclampsia were induced in pregnant rats by injections of the angiogenesis inhibitor Suramin. These alterations were aggravated by maternal diabetes and partly rectified by vitamin E supplementation. In the present study we evaluated the morphology of placentae and kidneys in this model. Non-diabetic and streptozotocin-induced diabetic pregnant rats of two rat strains (U and H) were treated with Suramin or saline, and given standard or vitamin E-enriched food. On gestational day 20 one placenta and the left kidney of the mother were collected for morphological and stereological analysis. In the placental trophospongium Suramin treatment caused cysts, which were further enhanced by maternal diabetes. Vitamin E treatment had no effect on the vacuolization. In the placental labyrinth of the non-diabetic rats Suramin treatment restricted maternal placental blood volume and increased the interface between maternal and fetal circulation. These changes were reversed by vitamin E treatment. Diabetes increased slightly the interface between the circulations in both rat strains. Suramin treatment decreased the interface, and vitamin E further decreased the interface in the diabetic U rats, whereas neither treatment affected the maternal-fetal interface in the diabetic H rats. The kidneys of Suramin-treated and diabetic rats were heavier compared to controls. Suramin treatment and maternal diabetes damaged renal glomeruli to a similar extent. Vitamin E treatment diminished the Suramin- and diabetes-induced glomerular damage in U rats, but not in H rats. The average cell count per glomerulus was decreased by Suramin in the U rats. Vitamin E treatment did not affect cell number per glomerulus in any group. We conclude that Suramin-injected pregnant rats constitute a valid animal model for placental dysfunction and pre-eclampsia, also from the histological perspective. The present work supports the notion that one important effect of untreated maternal diabetes may be impaired placentation, leading to oxidative stress, morphological damage, and compromised placental function.

Increased levels of several retinoid binding proteins resulting from retinoic acid-induced differentiation of F9 cells.

The embryonal carcinoma cell line F9 is known to differentiate when exposed to retinoic acid. We have examined the quantities of two intracellular retinoid-binding proteins in undifferentiated and differentiated F9 cells. The existence of a cell surface receptor that recognizes the plasma retinol-binding protein was also explored. It was shown that undifferentiated F9 cells contain low concentrations of the two retinoid-binding proteins. The cellular retinoic acid-binding protein was present in approximately 3-fold molar excess over the cellular retinol-binding protein. Upon culture in the presence of retinoic acid, F9 cells display elevated concentrations of both cellular retinol-binding protein and cellular retinoic acid-binding protein. Since the levels of beta 2-microglobulin, a marker of the differentiated state with no known involvement in the metabolism of vitamin A, increased in parallel with the retinoid-binding proteins, it seems unlikely that retinoic acid selectively increased the levels of the two retinoid-binding proteins. The differentiated, in contrast to the undifferentiated cells, can accumulate retinol from plasma retinol-binding protein and display a cell surface receptor for this protein. Despite the fact that retinoic acid-induced differentiation of F9 cells promotes increased levels of several proteins involved in the normal metabolism of vitamin A, no evidence was obtained to suggest that the cells were dependent on retinoids to maintain their differentiated state.

Soluble Vascular Cell Adhesion Molecule-1 (VCAM-1) as a Biomarker in the Mouse Model of Experimental Autoimmune Myocarditis (EAM).

Vascular cell adhesion molecule-1 (VCAM-1) is strongly upregulated in hearts of mice with coxsackie virus-induced as well as in patients with viral infection-triggered dilated cardiomyopathy. Nevertheless, the role of its soluble form as a biomarker in inflammatory heart diseases remains unclear. Therefore, we investigated whether plasma levels of soluble VCAM-1 (sVCAM-1) directly correlated with disease activity and progression of cardiac dysfunction in the mouse model of experimental autoimmune myocarditis (EAM). EAM was induced by immunization of BALB/c mice with heart-specific myosin-alpha heavy chain peptide together with complete Freund`s adjuvant. ELISA revealed strong expression of cardiac VCAM-1 (cVCAM-1) throughout the course of EAM in immunized mice compared to control animals. Furthermore, sVCAM-1 was elevated in the plasma of immunized compared to control mice at acute and chronic stages of the disease. sVCAM-1 did not correlate with the degree of acute cardiac inflammation analyzed by histology or cardiac cytokine expression investigated by ELISA. Nevertheless, heart to body weight ratio correlated significantly with sVCAM-1 at chronic stages of EAM. Cardiac systolic dysfunction studied with positron emission tomography indicated a weak relationship with sVCAM-1 at the chronic stage of the disease. Our data provide evidence that plasma levels of sVCAM-1 are elevated throughout all stages of the disease but showed no strong correlation with the severity of EAM.