Biomedical subjects

Per Eriksson

Publications and source records attributed to Per Eriksson.

At least 37 records · Page 2Linked to original sources

PubMed2005

Expression of neutrophil gelatinase-associated lipocalin in atherosclerosis and myocardial infarction.

OBJECTIVE: Neutrophil gelatinase-associated lipocalin (NGAL) modulates the activity of matrix metalloproteinase (MMP) 9, an important mediator of vascular remodeling and plaque instability in atherosclerosis. This study aimed to analyze the expression of NGAL in atherosclerotic plaques and myocardial infarction (MI). METHODS AND RESULTS: Atherosclerotic apolipoprotein E (apoE)(-/-) x low-density lipoprotein receptor (LDLR)(-/-) and C57BL/6J control mice were exposed to brief hypoxic stress (10 minutes of 10% oxygen). Expression of the mouse NGAL homolog (24p3) and MMP-9 was analyzed 48 hours later by quantitative RT-PCR, immunohistochemistry, and zymography. Hypoxic stress increased NGAL/24p3 mRNA in the cardiac vasculature. NGAL/24p3 was also increased in atherosclerotic plaques of apolipoprotein E(-/-) x LDLR(-/-) mice compared with C57BL/6J mice. Mice developing MI exhibited the highest plaque mRNA expression of NGAL/24p3 and MMP-9. Zymography revealed strong proteolytic activity in areas rich in 24p3 and MMP-9 protein. Immunohistochemistry performed on human carotid endarterectomy specimens and control tissue from the internal mammary artery showed colocalization of MMP-9 and NGAL with macrophages in the atherosclerotic plaques. CONCLUSIONS: NGAL/24p3 is increased in atherosclerotic plaques and MI. Colocalization with MMP-9 in areas with high-proteolytic activity suggests a role for NGAL/24p3 in modulating the MMP-9-mediated remodeling of plaques and infarcted hearts.

Acute-Phase Proteins↗

PubMed2005

Haplotype effect of the matrix metalloproteinase-1 gene on risk of myocardial infarction.

Myocardial infarction (MI) is commonly caused by atherosclerotic plaque rupture following excessive degradation of collagen fibers in the atherosclerotic lesion. We investigated whether interindividual variability in risk of MI was related to polymorphisms in the gene encoding matrix metalloproteinase (MMP)-1, a key fibrillar collagen-degrading enzyme. Several single nucleotide polymorphisms in the MMP1 gene promoter were identified following sequencing DNA samples from 30 individuals. An analysis of the polymorphisms in a cohort of British whites with coronary atherosclerosis, including 639 patients with MI and 538 non-MI subjects, revealed a haplotype effect of the -519A>G and -340T>C polymorphisms on risk of MI, with the A(-519)-C(-340) and G(-519)-T(-340) haplotypes being protective (odds ratio=0.70 [0.57 to 0.86]; P=0.0007), whereas the G(-519)-C(-340) haplotype increased MI risk (odds ratio=1.94 [1.15 to 3.28]; P=0.013). This finding was replicated in a subsequent analysis of 387 Swedish MI patients and 387 healthy controls (odds ratio=0.70 [0.55 to 0.89], P=0.003, for A(-519)-C(-340) and G(-519)-T(-340); odds ratio=1.54 [0.97 to 2.46], P=0.07, for G(-519)-C(-340)). In vitro assays showed that compared with the A(-519)-T(-340) haplotype, the A(-519)-C(-340) and G(-519)-T(-340) haplotypes had lower promoter activity, whereas the G(-519)-C(-340) haplotype had greater promoter strength, in driving gene expression in human macrophages. Haplotype-specific differences in MMP1 mRNA level in atherosclerotic tissues were also detected. The data indicate that MMP1 gene variation is a genetic factor contributing to interindividual differences in MI risk.

Adult↗

PubMed2005

Plasminogen activator inhibitor-1 4G/5G polymorphism and risk of stroke: replicated findings in two nested case-control studies based on independent cohorts.

BACKGROUND AND PURPOSE: Impaired fibrinolytic function secondary to elevated plasminogen activator inhibitor-1 (PAI-1) levels has been implicated in ischemic stroke. PAI-1 levels are determined by genetic factors and environmental factors, triglyceride levels in particular. The aim of this study was to investigate the common functional 4/5 guanosine (4G/5G) polymorphism in the promoter region of the PAI-1 gene and the risk of stroke. METHODS: A nested case-control study design was applied, using baseline data for 2 independent cohorts obtained at population-based surveys in northern Sweden. In study A, there were 113, and in study B, there were 275 individuals without major concomitant disease at baseline who later experienced a first-ever stroke. Blood samples obtained at baseline were analyzed for potential risk factors, including the 4G/5G polymorphism of the PAI-1 gene. RESULTS: The 4G allele of the PAI-1 polymorphism was associated with an increased risk of future ischemic stroke in both studies (odds ratio [OR] of 4G homozygosity, 1.87; 95% CI, 1.12 to 3.15 in study A; OR of 4G homozygosity, 1.56; 95% CI, 1.12 to 2.16 in study B). Individuals with the combination of hypertriglyceridemia and 4G homozygosity were at the greatest risk of developing stroke. Multiple logistic regression analysis identified 4G homozygosity, systolic blood pressure, and diabetes as independent predictors of ischemic stroke. CONCLUSIONS: Identical findings in 2 independent studies strongly suggest a true and clinically important association between PAI-1 4G/5G genotype and risk of future ischemic stroke. The observed modification of the genotype effect by triglycerides may be interpreted as a gene-environment interaction.

Adult↗

PubMed2005

High-density lipoproteins induce transforming growth factor-beta2 expression in endothelial cells.

BACKGROUND: HDL is endowed with cardiovascular protective activities. In addition to its role in reverse cholesterol transport, HDL influences different functions of endothelial cells. In the present study, we investigated in endothelial cells the genes involved in inflammation modulated by HDL. METHODS AND RESULTS: Through cDNA array analysis, transforming growth factor (TGF)-beta2 appeared to be a gene responsive to HDL treatment in endothelial cells. Quantitative real-time polymerase chain reaction confirmed that HDL subfraction 3 selectively induces TGF-beta2 mRNA expression and protein release, whereas TGF-beta1 and TGF-beta3 were not affected. This effect was mainly PI3K/Akt dependent. Lysosphingolipids present in HDL such as sphingosine 1 phosphate and sphingosylphosphorylcholine mimicked the effects of the whole HDL. These results were confirmed in vivo in transgenic mice overexpressing human apolipoprotein (apo) A-I. Compared with apoA-I-knockout mice, phospho-Akt, phospho-ERK1/2, and TGF-beta2 expression was increased in the aorta of transgenic mice overexpressing human apoA-I. In addition, the expression of phospho-Smad2/3, the transcription factor activated by TGF-beta, is increased in transgenic mice compared with knockout mice. CONCLUSIONS: Because TGF-beta possesses antiinflammatory properties and stabilizes the plaque, the results of the present work suggest a novel target for the antiatherosclerotic effect of HDL.

Animals↗

PubMed2005

Difference in matrix-degrading protease expression and activity between thrombus-free and thrombus-covered wall of abdominal aortic aneurysm.

OBJECTIVE: It has been suggested that the intraluminal thrombus of abdominal aortic aneurysms (AAAs) predisposes for AAA rupture. Here, we examined the possibility that the intraluminal thrombus influences expression and activity of matrix-degrading proteases in the AAA wall. METHODS AND RESULTS: Twenty patients undergoing elective repair of AAAs were included. From each patient, specimens from both thrombus-covered and thrombus-free wall were taken for analysis. Gene arrays and quantitative real-time polymerase chain reaction showed that matrix metalloproteinase (MMP)-1, -7, -9, and -12 expressions were upregulated in the thrombus-free wall compared with the thrombus-covered wall. Immunohistochemistry confirmed the differential expression of MMP-9 but also localized MMP-9 to the interface between the thrombus and the underlying vessel wall. MMP-9 expression was colocalized with the presence of macrophages. Similar expression patterns were observed for urokinase plasminogen activator (uPA), uPA receptor, and plasminogen activator inhibitor-1. Gelatinase activity was detected in the same regions as MMP-9 protein expression, ie, within the thrombus-free wall and in the interface between the thrombus and the underlying wall. CONCLUSIONS: The present work demonstrates that protease expression and activity differs within the aneurysm wall. The source and activity of the proteases responsible for the degradation of the thrombus-covered wall need to be further determined.

Aorta, Abdominal↗

PubMed2005

Human neuropeptide Y signal peptide gain-of-function polymorphism is associated with increased body mass index: possible mode of function.

Neuropeptide Y (NPY) has been implicated in the control of food intake and energy balance based on many observations in animals. We have studied single nucleotide polymorphisms (SNPs) within the regulatory and coding sequences of the human NPY gene. One variant (1128 T>C), which causes an amino acid change from leucine to proline at codon 7 in the signal peptide of NPY, was associated with increased body mass index (BMI) in two separate Swedish populations of normal and overweight individuals. In vitro transcription and translation studies indicated the unlikelihood that this signal peptide variation affects the site of cleavage and targeting or uptake of NPY into the endoplasmic reticulum (ER). However, the mutant, and to a lesser extent the wild-type, signal peptide by themselves markedly potentiated NPY-induced food intake, as well as hypothalamic NPY receptor signaling. Our findings in humans strongly indicate that the NPY signaling system is implicated in body weight regulation and suggest a new and unexpected functional role of a signal peptide.

Animals↗

PubMed2005

MHC2TA is associated with differential MHC molecule expression and susceptibility to rheumatoid arthritis, multiple sclerosis and myocardial infarction.

Antigen presentation to T cells by MHC molecules is essential for adaptive immune responses. To determine the exact position of a gene affecting expression of MHC molecules, we finely mapped a previously defined rat quantitative trait locus regulating MHC class II on microglia in an advanced intercross line. We identified a small interval including the gene MHC class II transactivator (Mhc2ta) and, using a map over six inbred strains combined with gene sequencing and expression analysis, two conserved Mhc2ta haplotypes segregating with MHC class II levels. In humans, a -168A --> G polymorphism in the type III promoter of the MHC class II transactivator (MHC2TA) was associated with increased susceptibility to rheumatoid arthritis, multiple sclerosis and myocardial infarction, as well as lower expression of MHC2TA after stimulation of leukocytes with interferon-gamma. We conclude that polymorphisms in Mhc2ta and MHC2TA result in differential MHC molecule expression and are associated with susceptibility to common complex diseases with inflammatory components.

Animals↗

PubMed2005

Positional identification of TNFSF4, encoding OX40 ligand, as a gene that influences atherosclerosis susceptibility.

Ath1 is a quantitative trait locus on mouse chromosome 1 that renders C57BL/6 mice susceptible and C3H/He mice resistant to diet-induced atherosclerosis. The quantitative trait locus region encompasses 11 known genes, including Tnfsf4 (also called Ox40l or Cd134l), which encodes OX40 ligand. Here we report that mice with targeted mutations of Tnfsf4 had significantly (P <or= 0.05) smaller atherosclerotic lesions than did control mice. In addition, mice overexpressing Tnfsf4 had significantly (P <or= 0.05) larger atherosclerotic lesions than did control mice. In two independent human populations, the less common allele of SNP rs3850641 in TNFSF4 was significantly more frequent (P <or= 0.05) in individuals with myocardial infarction than in controls. We therefore conclude that Tnfsf4 underlies Ath1 in mice and that polymorphisms in its human homolog TNFSF4 increase the risk of myocardial infarction in humans.

Aged↗

PubMed2005

A common beta2-adrenoceptor gene haplotype protects against obesity in Swedish women.

The beta2-adrenoceptor gene may be of particular importance for human obesity because catecholamines have a central role in energy expenditure both as neurotransmitters and hormones. The gene is highly polymorphic, and individual polymorphisms have previously been examined for their relationship to obesity, but results are conflicting. We performed a haplotype analysis of the beta2-adrenoceptor gene in 1354 women and 421 men, all healthy and at least second generation Scandinavian and with a large interindividual variation in body fat mass. We found three common haplotypes. One of these haplotypes, identified as T, A, C, C at nucleotide positions -47, 46, 79, and 491, was in its homozygote form more common among lean (18%) than obese (13%) women (p = 0.0028), but there was no association with obesity in men (p = 0.47). Women who were homozygous for this haplotype had lower BMI (p = 0.009) and percentage body fat (p = 0.005) in comparison with those having other haplotypes or being heterozygous for TACC. The data suggest an important role of the beta2-adrenoceptor gene in obesity because a common haplotype has recessive protective effects against excess body fat, at least in women.

Adult↗

PubMed2005

The effect of percutaneous dilatation of renal arterial stenosis on captopril renography in hypertension.

BACKGROUND: The clinical effects of percutaneous transluminal renal artery angioplasty (PTRA) in patients with renal vascular stenosis and hypertension is controversial. METHODS: We consecutively recruited all 23 patients referred for evaluation of renovascular hypertension that eventually underwent unilateral PTRA, to be investigated with captopril MAG3 renography (CR), both before and after the endovascular procedure. Data were evaluated on an intention-to-treat basis. RESULTS: We found that the relative MAG3 clearance of the stenotic kidney increased (from 29.9+/-14% to 35.1+/-14%, p=0.01) and that the creatinine levels fell following the intervention (from 110+/-19 to 99+/-17 micromol/l, p=0.0003). Blood pressure levels were also lowered (from 173+/-32/93+/-17 to 158+/-31/86+/-15 mmHg, p<0.006) while the mean number of anti-hypertensive drugs was unchanged following PTRA (2.9+/-1.4 before and 2.8+/-1.3 drugs after the intervention, respectively, p=0.6). CONCLUSION: This prospective trial showed statistically significant improvements of individual kidney function as measured by CR and blood pressure in subjects with suspected renovascular hypertension treated with PTRA. Although the endovascular procedure was found to be safe, the magnitude of the absolute improvements was rather modest.

Adult↗

PubMed2005

Apoptosis and angiogenesis are induced in the unstable coronary atherosclerotic plaque.

OBJECTIVE: Apoptosis and angiogenesis may be involved in the pathogenesis of atherosclerosis and plaque destabilization. In this study, we investigated if apoptosis and angiogenesis were induced in the unstable human coronary atherosclerotic plaque compared to stable atherosclerotic plaque. METHODS: Atherosclerotic plaques from patients with stable (n = 9) and unstable angina (n = 13) were obtained by directional coronary atherectomy performed during percutaneous transluminal coronary angioplasty. Apoptosis was detected by terminal deoxynucleotidyl transferase end labelling (TUNEL), as well as by immunostaining for caspase 3, Bax and Bcl-2. Neovascularization was determined by immunostaining for the endothelial cell-specific CD31, vascular endothelial growth factor (VEGF-A), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), hypoxia inducible factor-1alpha (HIF-alpha), and the sections were quantified blindly. RESULTS: The apoptotic nuclei were more frequently found in the unstable coronary atherosclerotic plaques. When the number of apoptotic cells was quantified, an increased apoptotic index was found in the unstable plaques (P = 0.04). The positive staining for caspase-3 was increased in the unstable plaques (P = 0.0008), while no difference in either Bax or Bcl-2 was found between groups. Neovascularization, as evidenced by lumens surrounded by a CD31 positive endothelial layer, was more frequently present in the plaques from patients with unstable angina (P = 0.04). The number of cells with positive staining for VEGF-A was increased in unstable plaques (P = 0.005). No difference of Ang I, Ang II, HIF1-alpha was found between groups. CONCLUSIONS: In unstable human coronary plaques, apoptosis probably involving caspase 3 was found. The plaques had an increased neovascularization, probably induced by VEGF-A. These factors may contribute to explaining plaque destabilization and intraplaque haemorrhage.

Aged↗

PubMed2005

Contribution of haplotypes across the fibrinogen gene cluster to variation in risk of myocardial infarction.

Fibrinogen has consistently been recognized as an independent predictor of myocardial infarction (MI). Multiple mechanisms link fibrinogen to MI; therefore disentangling the factors underlying variation in plasma fibrinogen concentration is essential. Candidate regions in the fibrinogen gamma (FGG), alpha (FGA) and beta (FGB) genes were screened for single nucleotide polymorphisms (SNPs). Several novel SNPs were detected in the FGG and FGA genes in addition to the previously known SNPs in the fibrinogen genes. Tight linkage disequilibrium extending over various physical distances was observed between most SNPs. Consequently, eight SNPs were chosen and determined in 377 postinfarction patients and 387 healthy individuals. None of the SNPs were associated with plasma fibrinogen concentration or MI. Haplotype analyses revealed a consistent pattern of haplotypes associated with variation in risk of MI. Of the four haplotypes inferred using the FGA -58G>A and FGG 1299 +79T>C SNPs, the most frequent haplotype, FGG-FGA*1 (prevalence 46.6%), was associated with increased risk of MI (OR 1.51; 95%CI 1.18, 1.93), whereas the least frequent haplotype, FGG-FGA*4 (11.8%), was associated with lower risk of MI (OR 0.79 95%CI 0.64, 0.98). In conclusion, fibrinogen haplotypes, but not SNPs in isolation, are associated with variation in risk of MI.

Case-Control Studies↗

PubMed2005

Expression of matrix metalloproteinase 9 and its regulators in the unstable coronary atherosclerotic plaque.

Unstable coronary syndromes, initiated by rupture of an atherosclerotic plaque, may involve the activation of matrix metalloproteinases (MMPs). The regulation of MMP activity is complex and involves three steps. First, an inactive pro-MMP is transcriptionally regulated, a process that is likely to involve the transcription factor activator protein-1 (AP-1) and nuclear factor kappa B (NF-kappaB). Secondly, the pro-MMP is proteolytically cleaved into an active MMP. Plasmin has been suggested to be the major activator of MMPs in vivo. Thirdly, the activated MMP can be inhibited by tissue inhibitors of metalloproteinase (TIMPs). We investigated if expression of MMP9 and its potential regulators are induced in unstable coronary plaques. Atherosclerotic plaques from patients with stable (n=22) and unstable (n=39) angina were obtained by directional coronary atherectomy and analysed by semiquantitative RT-PCR and immunohisto-chemistry. Plasma was collected for ELISA analysis. mRNA for MMP9 as well as plasminogen activator inhibitor-1 (PAI-1) was increased in unstable plaques, while tissue type plasminogen activator (tPA) expression was similar in stable and unstable plaques. Plaques from unstable patients had an increased infiltration of macrophages and T-lymphocytes, nuclear localisation of AP-1 and the NF-kappaB subunit p65, as well as increased positive immunostaining for MMP9 and tPA. Plasma MMP9 antigen was elevated in unstable patients. MMP9 is expressed in the unstable coronary atherosclerotic plaque, as are its transcriptional and posttranscriptional regulators.

Adult↗

PubMed2004

Genotypic effect of the -565C>T polymorphism in the ABCA1 gene promoter on ABCA1 expression and severity of atherosclerosis.

OBJECTIVE: Loss-of-function mutations of the ATP-binding cassette transporter A1 (ABCA1) gene cause Tangier disease, a rare genetic disorder with accumulation of lipid-laden macrophages and increased risk of atherosclerosis. Common variants of this gene may be a genetic factor for atherosclerosis in the general population. This study was performed to test the reported association between the -565C>T polymorphism and atherosclerosis severity and to investigate whether this variant per se had an effect on promoter activity of the ABCA1 gene. METHODS AND RESULTS: A cohort of patients with coronary atherosclerosis were genotyped for the -565C>T polymorphism. Logistic regression analyses showed that homozygotes of the -565T allele had greatest mean number of diseased coronary arteries, particular in nonsmokers. Real-time reverse-transcriptase polymerase chain reaction showed that in atherosclerotic plaques removed from patients undergoing endarteretomy, ABCA1 expression levels were lowest in those who had the T/T genotype and highest in those of the C/C genotype. Transfection and reporter assays demonstrated that in cultured macrophages, the -565T allelic promoter had a lower activity in driving gene expression than the -565C allelic promoter. Electrophoretic mobility shift assays displayed differential binding of nuclear proteins to the 2 alleles. CONCLUSIONS: These results indicate that the -565C>T polymorphism has an allele-specific effect on ABCA1 gene expression and provide further evidence of a genotypic effect on coronary atherosclerosis severity. The study showed that the ABCA1 gene -565C>T polymorphism was associated with severity of coronary atherosclerosis in a cohort of patients from Southern England and that this sequence variant per se had an effect on promoter activity of the ABCA1 gene. The data support the notion that common ABCA1 gene variants can contribute to interindividual variability in atherosclerosis susceptibility and severity.

ATP Binding Cassette Transporter 1↗

PubMed2004

Increased susceptibility to adult paraoxon exposure in mice neonatally exposed to nicotine.

Low-dose exposure of neonatal mice to nicotine has earlier been shown to induce an altered behavioral response to nicotine in adulthood. Organophosphorus insecticides are known to affect the cholinergic system by inhibition of acetylcholinesterase. This study was undertaken to investigate whether neonatal exposure to nicotine makes mice more susceptible to a known cholinergic agent. Neonatal, 10-day-old, male mice were exposed to nicotine-base (33 microg/kg body weight) or saline s.c. twice daily on five consecutive days. At 5 months of age the animals were exposed to paraoxon (0.17 or 0.25 mg/kg body weight [29% and 37% inhibition of cholinesterase, respectively]) or saline sc every second day for 7 days. Before the first paraoxon injection, the animals were observed for spontaneous motor behavior. The spontaneous motor behavior test did not reveal any differences in behavior between the treatment groups. Immediately after the spontaneous behavior test, the animals received the first injection of paraoxon and were observed for acute effects of paraoxon on spontaneous motor behavior. The acute response to paraoxon in the spontaneous motor behavior test was a decreased level of activity in mice neonatally exposed to nicotine. Control animals showed no change in activity. Two months after the paraoxon treatment, the animals were again tested for spontaneous motor behavior. Animals neonatally exposed to nicotine and exposed to paraoxon as adults showed a deranged spontaneous motor behavior, including hyperactivity and lack of habituation.

Animals↗

PubMed2004

Neurofunctional deficits and potentiated apoptosis by neonatal NMDA antagonist administration.

The early postnatal brain development, when many potentially sensitive processes occur, has been shown to be vulnerable to different pharmacological and environmental compounds. In the present investigation, four groups of neonatal NMRI male mice were administered the glutamate NMDA receptor antagonist ketamine (50 mg/kg, s.c.), or the GABA(A) receptor agonist diazepam (5 mg/kg, s.c.), or co-administered ketamine (50 mg/kg, s.c.) and diazepam (5 mg/kg, s.c.), or vehicle (0.9% saline, s.c.) on day 10 after birth. On day 11, mice from each treatment group were sacrificed and brains were taken for analysis of neuronal cell degeneration, using Fluoro-Jade staining technique. Ketamine, but not diazepam, induced a severe degeneration of cells in the parietal cortex. The opposite was observed for diazepam in the laterodorsal thalamus. The most pronounced cell degeneration was seen in parietal cortex of mice exposed to both ketamine and diazepam. At 2 months of age each treatment group was tested for motor activity and learning performance. Ketamine and ketamine + diazepam treated mice displayed severe deficits of habituation to the test chamber in the spontaneous motor activity test, marked deficits of acquisition learning and retention memory in the radial arm maze-learning task and less shift learning in the circular swim maze-learning task. This study indicates that the observed functional deficits can be related to cell degeneration induced during a critical stage of neonatal brain development. The potentiated apoptosis induced by ketamine and diazepam may have implications for the selection of drugs used in neonatal paediatric anaesthesia.

Animals↗

PubMed2004

Dose-response modeling and benchmark calculations from spontaneous behavior data on mice neonatally exposed to 2,2',4,4',5-pentabromodiphenyl ether.

In this paper the benchmark dose (BMD) method was introduced for spontaneous behavior data observed in 2-, 5-, and 8-month-old male and female C57Bl mice exposed orally on postnatal day 10 to different doses of 2,2',4,4',5-pentabromodiphenyl ether (PBDE 99). Spontaneous behavior (locomotion, rearing, and total activity) was in the present work quantified in terms of a fractional response defined as the cumulative response after 20 min divided by the cumulative response produced over the whole 1-h test period. The fractional response contains information about the time-response profile (which differs between the treatment groups) and has appropriate statistical characteristics. In the analysis, male and female mice could be characterized by a common dose-response model (i.e., they responded equally to the exposure to PBDE 99). As a primary approach, the BMD was defined as the dose producing a 5 or 10% change in the mean fractional response. According to the Hill model, considering a 10% change the lower bound of the BMD for rearing, locomotion, and total activity was 1.2, 0.85, and 0.31 mg PBDE 99/kg body weight, respectively. A probability-based procedure for BMD modeling was also considered. Using this methodology, the BMD was defined as corresponding to an excess risk of 5 or 10% of falling below cutoff points representing adverse levels of fractional response.

Algorithms↗

PubMed2004

Investigations of strain and/or gender differences in developmental neurotoxic effects of polybrominated diphenyl ethers in mice.

Polybrominated diphenyl ethers (PBDEs), one class of flame retardants used to suppress or inhibit the risk of fire, are regularly found in the environment and in human milk. The present study shows that neonatal exposure to a widely, environmentally found PBDE, 2,2',4,4',5-pentaBDE (PBDE 99), can induce developmental neurotoxic effects, such as changes in spontaneous behavior (hyperactivity), effects that are dose-response related and worsen with age. These changes are seen in C57/Bl mice of both sexes. Neonatal C57/Bl male and female mice were orally exposed on day 10 to 0.4, 0.8, 4.0, 8.0, or 16 mg PBDE 99/kg body weight. Spontaneous behavior (locomotion, rearing, and total activity) was observed in two-, five-, and eight-month-old mice. The behavior tests showed that the effects were dose-response and time-response related for both male and female mice. The observed developmental neurotoxic effects seen for PBDE 99, in C57/Bl mice, are similar to effects seen for 2,2',4,4'-tetraBDE (PBDE 47), PBDE 99, 2,2',4,4',5,5'- hexaBDE (PBDE 153), 2,2',3,3',4,4',5,5',6,6'-decaBDE (PBDE 209) and for certain PCBs, in male NMRI mice. Furthermore, the effects of PBDEs appear to be as potent in female mice as in male mice, and as potent in C57/Bl mice as in NMRI mice, concerning developmental neurotoxicity.

Animals↗