145 research outputs found
Inflammatory mediators and cell adhesion molecules as indicators of severity of atherosclerosis: the Rotterdam Study
Inflammatory mediators and soluble cell adhesion molecules predict
cardiovascular events. It is not clear whether they reflect the severity
of underlying atherosclerotic disease. Within the Rotterdam Study, we
investigated the associations of C-reactive protein (CRP), interleukin-6
(IL-6), soluble intercellular adhesion molecule-1, and soluble vascular
cell adhesion molecule-1 with noninvasive measures of atherosclerosis.
Levels of CRP were assessed in a random sample of 1317 participants, and
levels of IL-6 and soluble cell adhesion molecules were assessed in a
subsample of 714 participants. In multivariate analyses, logarithmically
transformed CRP (regression coefficient [beta]=-0.023, 95% CI -0.033 to
-0.012) and IL-6 (beta=-0.025, 95% CI -0.049 to -0.001) were inversely
associated with the ankle-arm index. Only CRP was associated with carotid
intima-media thickness (beta=0.018, 95% CI 0.010 to 0.027). Compared with
the lowest tertile, the odds ratio for moderate to severe carotid plaques
associated with levels of CRP in the highest tertile was 2.0 (95% CI 1.3
to 3.0). Soluble intercellular adhesion molecule-1 levels were strongly
associated with carotid plaques (odds ratio 2.5, 95% CI 1.5 to 4.4
[highest versus lowest tertile]). Soluble vascular cell adhesion
molecule-1 was not significantly associated with any of the measures of
atherosclerosis. This study indicates that CRP is associated with the
severity of atherosclerosis measured at various sites. Associations of the
other markers with atherosclerosis were less consistent
Markers of inflammation and cellular adhesion molecules in relation to insulin resistance in nondiabetic elderly: the Rotterdam study
Insulin resistance, which is highly prevalent in the elderly, is suggested
to be accompanied by an increased acute phase response. Until now, it is
unclear whether cellular adhesion molecules are involved in the clustering
of insulin resistance. In the present study, we examined the relationship
of insulin resistance (measured by postload insulin) with levels of
markers of inflammation and cellular adhesion molecules in a random sample
of 574 nondiabetic elderly men and women participating in the Rotterdam
Study. Associations were assessed by regression analysis, with ln-insulin
as the dependent variable [regression coefficient (95% confidence
interval)]. In our population, insulin was strongly and significantly (P <
0.001) associated with the markers of inflammation C-reactive protein
[1.52 (0.96-2.08)], alpha-1-antichymotrypsin [1.25 (0.82-1.69)], and IL-6
[2.60 (1.69-3.52)], adjusted for age and gender. Associations weakened, to
some extent, after additional adjustment for measures of obesity, smoking,
and cardiovascular disease. Insulin was associated with the soluble
intercellular adhesion molecule 1 [2.22 (1.29-3.16; P < 0.001)], whereas
no association with the soluble vascular cell adhesion molecule 1 was
found. The strength of the associations of insulin with C-reactive
protein, alpha-1-antichymotrypsin, IL-6, and soluble intercellular
adhesion molecule 1, as assessed by standardized regression coefficients,
was comparable with the strength of the associations of insulin with
high-density lipoprotein cholesterol, body mass index, and waist-to-hip
ratio. The results of this population-based study indicate that low-grade
inflammation and the cellular adhesion molecule soluble intercellular
adhesion molecule 1 are an integral part of insulin resistance in
nondiabetic elderly. These factors may contribute to the well-known
relationship between insulin resistance and cardiovascular disease risk
and might potentially become therapeutic targets in insulin resistant
subjects
Effects of early-life stress on peripheral and central mitochondria in male mice across ages
Exposure to early-life stress (ES) increases the vulnerability to develop metabolic diseases as well as cognitive dysfunction, but the specific biological underpinning of the ES-induced programming is unknown. Metabolic and cognitive disorders are often comorbid, suggesting possible converging underlying pathways. Mitochondrial dysfunction is implicated in both metabolic diseases and cognitive dysfunction and chronic stress impairs mitochondrial functioning. However, if and how mitochondria are impacted by ES and whether they are implicated in the ES-induced programming remains to be determined. ES was applied by providing mice with limited nesting and bedding material from postnatal day (P)2-P9, and metabolic parameters, cognitive functions and multiple aspects of mitochondria biology (i.e. mitochondrial electron transport chain (ETC) complex activity, mitochondrial DNA copy number, expression of genes relevant for mitochondrial function, and the antioxidant capacity) were studied in muscle, hypothalamus and hippocampus at P9 and late adulthood (10–12 months of age). We show that ES altered bodyweight (gain), adiposity and glucose levels at P9, but not in late adulthood. At this age, however, ES exposure led to cognitive impairments. ES affected peripheral and central mitochondria in an age-dependent manner. At P9, both muscle and hypothalamic ETC activity were affected by ES, while in hippocampus, ES altered the expression of genes involved in fission and antioxidant defence. In adulthood, alterations in ETC complex activity were observed in the hypothalamus specifically, whereas in muscle and hippocampus ES affected the expression of genes involved in mitophagy and fission, respectively. Our study demonstrates that ES affects peripheral and central mitochondria biology throughout life, thereby uncovering a converging mechanism that might contribute to the ES-induced vulnerability for both metabolic diseases and cognitive dysfunction, which could serve as a novel target for intervention.</p
White Matter Lesions Are Not Related to β-Amyloid Deposition in an Autopsy-Based Study
Population-based studies have investigated the relation between β-amyloid levels in cerebrospinal fluid or plasma and white matter lesions (WMLs). However, these circulating levels of β-amyloid in cerebrospinal fluid or plasma may not reliably reflect the actual degree of amyloid present in the brain. Therefore, we investigated the relation between WMLs and β-amyloid plaques and amyloid angiopathy in brain tissue. WML on MRI or CT were rated in 28 nondemented patients whose neuroimaging was available prior to death. β-amyloid in plaques and arterioles were immunohistochemically stained and quantified in postmortem brain necropsies. WMLs were present in 43% of the total population. Both cortex and periventricular region showed no differences for β-amyloid deposition in either plaques or blood vessel walls in patients with WMLs compared to those without WMLs. Thus, our results indicate that there is no relation between the degree of WMLs and β-amyloid deposition in the brain
Butyrate interacts with the effects of 2'FL and 3FL to modulate in vitro ovalbumin-induced immune activation, and 2'FL lowers mucosal mast cell activation in a preclinical model for hen's egg allergy.
BACKGROUND: Early life provides a window of opportunity to prevent allergic diseases. With a prevalence of 0.5-2% in infants, hen's egg allergy is one of the most common food allergies. The immunomodulatory effects of human milk oligosaccharides (HMOs), 2'-fucosyllactose (2'FL), and 3-fucosyllactose (3FL) were studied in an in vitro mucosal immune model and an in vivo murine model for hen's egg (ovalbumin) allergy. METHODS: Intestinal epithelial cell (IEC)/dendritic cell (DC) and DC/T cell cocultures were used to expose IECs to ovalbumin (OVA) in an in vitro mucosal immune model. The effects of epithelial pre-incubation with 0.1% 2'FL or 3FL and/or 0.5 mM butyrate were studied. Three- to four-weeks-old female C3H/HeOuJ mice were fed AIN93G diets containing 0.1-0.5% 2'FL or 3FL 2 weeks before and during OVA sensitization and challenge. Allergic symptoms and systemic and local immune parameters were assessed. RESULTS: Exposing IECs to butyrate in vitro left the IEC/DC/T cell cross-talk unaffected, while 2'FL and 3FL showed differential immunomodulatory effects. In 3FL exposed IEC-DC-T cells, the secretion of IFNγ and IL10 was enhanced. This was observed upon pre-incubation of IECs with 2'FL and butyrate as well, but not 2'FL alone. The presence of butyrate did not affect OVA activation, but when combined with 3FL, an increase in IL6 release from DCs was observed ( p < 0.001). OVA allergic mice receiving 0.5% 3FL diet had a lower %Th2 cells in MLNs, but the humoral response was unaltered compared to control mice. OVA-allergic mice receiving 0.1 or 0.5% 2'FL diets had lower serum levels of OVA-IgG2a ( p < 0.05) or the mast cell marker mMCP1, in association with increased concentration of cecal short-chain fatty acids (SCFAs) ( p < 0.05). CONCLUSION: In vitro butyrate exposure promotes the development of a downstream type 1 and regulatory response observed after 2'FL exposure. 2'FL and 3FL differentially modulate ovalbumin-induced mucosal inflammation predominantly independent of butyrate. Mice receiving dietary 3FL during ovalbumin sensitization and challenge had lowered Th2 activation while the frequency of Treg cells was enhanced. By contrast, 2'FL improved the humoral immune response and suppressed mast cell activation in association with increased SCFAs production in the murine model for hen's egg allergy
Ldlr-/-.Leiden mice develop neurodegeneration, age-dependent astrogliosis and obesity-induced changes in microglia immunophenotype which are partly reversed by complement component 5 neutralizing antibody
Introduction: Obesity has been linked to vascular dysfunction, cognitive impairment and neurodegenerative diseases. However, experimental models that recapitulate brain pathology in relation to obesity and vascular dysfunction are still lacking.Methods: In this study we performed the histological and histochemical characterization of brains from Ldlr-/-.Leiden mice, an established model for obesity and associated vascular disease. First, HFD-fed 18 week-old and 50 week-old Ldlr-/-.Leiden male mice were compared with age-matched C57BL/6J mice. We then assessed the effect of high-fat diet (HFD)-induced obesity on brain pathology in Ldlr-/-.Leiden mice and tested whether a treatment with an anti-complement component 5 antibody, a terminal complement pathway inhibitor recently shown to reduce vascular disease, can attenuate neurodegeneration and neuroinflammation. Histological analyses were complemented with Next Generation Sequencing (NGS) analyses of the hippocampus to unravel molecular pathways underlying brain histopathology.Results: We show that chow-fed Ldlr-/-.Leiden mice have more severe neurodegeneration and show an age-dependent astrogliosis that is not observed in age-matched C57BL/6J controls. This was substantiated by pathway enrichment analysis using the NGS data which showed that oxidative phosphorylation, EIF2 signaling and mitochondrial dysfunction pathways, all associated with neurodegeneration, were significantly altered in the hippocampus of Ldlr-/-.Leiden mice compared with C57BL/6J controls. Obesity-inducing HFD-feeding did not aggravate neurodegeneration and astrogliosis in Ldlr-/-.Leiden mice. However, brains from HFD-fed Ldlr-/-.Leiden mice showed reduced IBA-1 immunoreactivity and increased CD68 immunoreactivity compared with chow-fed Ldlr-/-.Leiden mice, indicating alteration of microglial immunophenotype by HFD feeding. The systemic administration of an anti-C5 treatment partially restored the HFD effect on microglial immunophenotype. In addition, NGS data of hippocampi from Ldlr-/-.Leiden mice showed that HFD feeding affected multiple molecular pathways relative to chow-fed controls: HFD notably inactivated synaptogenesis and activated neuroinflammation pathways. The anti-C5 treatment restored the HFD-induced effect on molecular pathways to a large extent.Conclusion: This study shows that the Ldlr-/-.Leiden mouse model is suitable to study brain histopathology and associated biological processes in a context of obesity and provides evidence of the potential therapeutic value of anti-complement therapy against obesity-induced neuroinflammation.</p
S-adenosylmethionine and S-adenosylhomocysteine levels in the aging brain of APP/PS1 Alzheimer mice
Hyperhomocysteinemia and factors of homocysteine metabolism, S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet), may play a role in Alzheimer’s disease (AD). With liquid-chromatography-tandem-mass-spectrometry AdoMet and AdoHcy were determined in brains of 8- and 15-month-old APP/PS1 Alzheimer mice, and their possible roles in AD brains investigated. The finding that AdoMet levels do not differ between the genotypes in (young) 8-month-old mice, but are different in (older) 15-month-old APP/PS1 mice compared to their wild-type littermates, suggests that alterations in AdoMet are a consequence of AD pathology rather than a cause. During aging, AdoMet levels decreased in the brains of wild-type mice, whereas AdoHcy levels diminished in both wild type and APP/PS1 mice. The finding that AdoMet levels in APP/PS1 mice are not decreased during aging (in contrast to wild-type mice), is probably related to less demand due to neurodegeneration. No effect of the omega-3 fatty acid docosahexaenoic acid (DHA) or cholesterol-enriched diets on AdoMet or AdoHcy levels were found
- …