Transfer of omega-3 fatty acids across the blood-brain barrier after dietary supplementation with a docosahexaenoic acid-rich omega-3 fatty acid preparation in patients with Alzheimer's disease: the OmegAD study.

OBJECTIVE: Little is known about the transfer of essential fatty acids (FAs) across the human blood-brain barrier (BBB) in adulthood. In this study, we investigated whether oral supplementation with omega-3 (n-3) FAs would change the FA profile of the cerebrospinal fluid (CSF). METHODS: A total of 33 patients (18 receiving the n-3 FA supplement and 15 receiving placebo) were included in the study. These patients were participants in the double-blind, placebo-controlled randomized OmegAD study in which 204 patients with mild Alzheimer's disease (AD) received 2.3 g n-3 FA [high in docosahexaenoic acid (DHA)] or placebo daily for 6 months. CSF FA levels were related to changes in plasma FA and to CSF biomarkers of AD and inflammation. RESULTS: At 6 months, the n-3 FA supplement group displayed significant increases in CSF (and plasma) eicosapentaenoic acid (EPA), DHA and total n-3 FA levels (P < 0.01), whereas no changes were observed in the placebo group. Changes in CSF and plasma levels of EPA and n-3 docosapentaenoic acid were strongly correlated, in contrast to those of DHA. Changes in DHA levels in CSF were inversely correlated with CSF levels of total and phosphorylated tau, and directly correlated with soluble interleukin-1 receptor type II. Thus, the more DHA increased in CSF, the greater the change in CSF AD/inflammatory biomarkers. CONCLUSIONS: Oral supplementation with n-3 FAs conferred changes in the n-3 FA profile in CSF, suggesting transfer of these FAs across the BBB in adults.

Simple advice on lifestyle habits and long-term changes in biomarkers of inflammation and vascular adhesion in healthy middle-aged men.

BACKGROUND/OBJECTIVES: Lifestyle habits, vascular function and inflammation are components in the development of cardiovascular disease (CVD). We investigated whether simple advice on dietary and exercise habits given (at a single time point) to hypercholesterolemic men affects circulating biomarkers of inflammation and vascular adhesion. SUBJECTS/METHODS: In total, 157 men (age 46±5 years) with mild hypercholesterolemia were randomized to four intervention groups, diet (D, n=40), exercise (E, n=39), diet and exercise (DE, n=39) or controls (C, n=39) and serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1) and soluble E-selectin (sE-selectin) were quantified at baseline and after a 6-month intervention period. RESULTS: The intervention applied in this study, that is, simple advice on lifestyle changes given at a single time point, had a modest effect on inflammatory biomarkers and soluble vascular adhesion molecules. The most apparent alterations were found for individuals in group DE, who responded with significant reductions in sICAM-1, -28 (-41 to -14 µg/l) and sE-selectin, -3.6 (-6.9 to -0.3 µg/l) after 6 months. None of the groups had altered their concentrations of sVCAM-1, CRP or IL-6 significantly after the intervention. In all individuals combined, we found changes in apolipoprotein B (apoB) to predict alterations in sICAM-1 (ß=0.21) and sE-selectin (ß=0.26), independently of changes in inflammation and other adhesion molecules. CONCLUSIONS: These observations indicate that even small efforts to improve diet and physical activity can influence biomarkers of vascular function in individuals at increased risk for CVD. ApoB was identified as an important determinant of this improvement, which adds further support to the notion of apoB as a critical target in cardiovascular prevention.

Polymorphisms in cytokine genes influence long-term survival differently in elderly male and female patients.

OBJECTIVES: We asked if single nucleotide polymorphisms (SNP) in inflammatory cytokine genes related to 3-year survival in ill elderly subjects and if genotypes differed between the elderly and a younger control population. DESIGN: Prospective observational study. SETTING: Two geriatric departments at a university hospital. SUBJECTS: Eighty three acutely admitted geriatric patients (83 +/- 7 year, 70% women) and 207 young healthy subjects (40 +/- 1 year, 37% women) were included. OUTCOME MEASURES: Single nucleotide polymorphisms in the genes of tumour necrosis factor (TNF)-alpha-308 G/A, interleukin (IL)-1beta-511 C/T, IL-6-174 G/C and IL-10-1082 A/G were analysed. In the geriatric patients SNP in lymphotoxin (LT)-alpha +252 G/A and serum levels of TNF-alpha, IL-6, IL-10, soluble IL-I receptor(R)II were also determined, as well as the 3-year mortality. RESULTS: The allele distribution did not differ significantly between the elderly and the young. In the female elderly, 3-year survival was doubled (P < 0.05) in those with the high-producing genotypes of IL-6 -174 GG and TNF-alpha -308 GA compared with those with low-producing alleles. In contrast, men with high-producing LT-alpha +252 AA and IL-1beta-511 CT&TT genotypes displayed halved 3-year survival (P < 0.05) compared with those with low-producing genotypes, whereas possession of the high-producing IL-10 -1082 GG genotype favoured survival. Serum IL-10 was higher in the high-producing IL-10 genotype in females. CONCLUSION: As high-producing IL-6 -174 genotype favoured 3-year survival in women, whereas the likewise high-producing LT-alpha +252 and IL-1beta -511 genotypes were associated with poor survival in men, we conclude that the specific genotypes, in association with gender, may act as determinants for survival in elderly patients.

Production and characterization of antibodies for the specific determination of the opioid peptide Met5-Enkephalin-Arg6-Phe7.

Endogenous opioids serve as modulators of neuroendocrine and immune system processes, the investigation of which calls for high-specificity radioimmunoassays (RIAs). This study focuses on the development and use of a specific radioimmunoassay for the opioid peptide Met5-Enkephalin-Arg6-Phe7 (MEAP), the C-terminus part of proenkephalin A. Antibodies were raised in four rabbits and investigated in terms of titre, avidity and specificity, followed by finding ideal conditions for these antibodies in RIA. MEAP concentrations were determined in crude extracts of rat hypothalamus, dorsal root ganglia, adrenals and ankle using this standardized assay after an oxidizing process. At reverse-phase high-pressure liquid chromatography (HPLC), the position of immunoreactive material from rat hypothalamus eluted as two peaks out of which one was compatible with that of synthetic MEAP. All rabbits exhibited individual differences in relative immune response and time of its onset. The avidity constant was 10 times higher on a molar basis for ab 4108 compared with ab 4182. There was no cross-reactivity for ab 4182 to related peptides, such as enkephalins and dynorphin B, and negligible background values for ab 4108. The relative levels ofimmunoreactive MEAP from the CNS versus peripheral tissues contrasted in accordance with current knowledge. It is suggested that reports with RIA results should include characterization of antibodies, extraction procedures, standard curves and compositions of buffers. Furthermore, the results should preferably be expressed in relation to total protein content.

Stimulation of tumor necrosis factor-alpha release from lipopolysaccharide-activated human blood monocytes by prostaglandin J2 and metabolites of prostaglandin J2.

Prostaglandin (PG) J2 and related compounds have anti-tumor effects in vivo. To investigate possible mechanisms for this we determined effects of PGD2, PGJ2 and two PGJ2 metabolites delta 12-PGJ2 and 15-deoxy-delta 12, delta 14 PGJ2 on tumor necrosis factor-alpha (TNF-alpha) release from blood monocytes in vitro. All PGJ2 compounds stimulated TNF-alpha-release from lipopolysaccharide-activated monocytes. By contrast, the parent prostaglandin PGD2 had no stimulatory effect. We conclude that the stimulatory effect of PGJ compounds on TNF-alpha formation might contribute to the antineoplastic properties of these compounds.

Comparative evaluation of a new molecular method for typing Staphylococcus epidermidis.

The discriminatory powers of several techniques for typing Staphylococcus epidermidis were evaluated in an epidemiological study of bacteria isolated from intensive care patients and from neonates. Genomic DNA fingerprinting using BclI restriction endonuclease was an effective epidemiological marker. The distinct restriction fragment profiles produced with this enzyme were highlighted with specific probes in a Southern blot technique. Cloned Escherichia coli rRNA gene probes proved to have lower discriminatory power and be less suitable for intraspecies typing. However, a panel of random genomic Staphylococcus epidermidis DNA clones provided almost the same level of discrimination as the DNA fingerprinting technique and also provided a clearer profile. DNA and gene fingerprinting techniques were reproducible and highly discriminatory compared to typing based on antigen and plasmid profiles, antibiotic susceptibility patterns and biotypes.

Cytokine release from mononuclear cells in patients irradiated for breast cancer.

Mononuclear cells from blood of 19 breast cancer patients were cultured in vitro before and following postoperative radiation treatment. Interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1) were determined in supernatants from stimulated and unstimulated cultures with or without addition of indomethacin. The release of all three cytokines was uninhibited in tumour patients. Spontaneous IL-1 secretion was increased in patients compared to controls. Indomethacin enhanced IFN-gamma release and spontaneous and induced TNF-alpha secretion in all groups but stimulated IL-1 only in irradiated patients. In patients with a low tumour burden, ability to produce cytokines seems to be unchanged although increased spontaneous IL-1 secretion indicates macrophage activation. Cyclooxygenase inhibition in conjunction with irradiation might be tried as a therapeutic modality in patients with cancer.

Indomethacin modulation of monocyte cytokine release following pelvic irradiation for cancer.

Pelvic irradiation for urogenital cancer reduced monocyte release of tumour necrosis factor alpha (TNF-alpha). Addition of indomethacin to monocyte cultures increased TNF-alpha production after but not before irradiation. E. coli lipopolysaccharide (LPS) increased TNF-alpha release before as well as after radiation therapy and addition of indomethacin to LPS-stimulated monocytes further increased TNF-alpha production following radiotherapy. Spontaneous interleukin-1 (IL-1) release was increased in the cancer patients and was not significantly affected by radiation therapy. LPS increased IL-1 release before as well as after irradiation, but indomethacin did not further change IL-1 secretion. These findings suggest that prostaglandins differentially regulate TNF-alpha and IL-1 release. Administration of cyclo-oxygenase inhibitors during radiation therapy might increase TNF-alpha release in vivo and thereby enhance the host defence against tumours.

Modulation of lymphocyte and monocyte responses in vitro by 9-deoxy-delta 9-prostaglandin D2 and 9-deoxy-delta 9-delta 12-prostaglandin D2.

The effects of 9-deoxy-delta 9-prostaglandin D2 (PGJ2) and 9-deoxy-delta 9-delta 12-prostaglandin D2 (delta 12PGJ2), which are metabolites of PGD2, on lymphocyte and monocyte reactions were studied in vitro. Expression of various phenotypic markers of lymphocyte subsets, as detected by monoclonal antibodies, was not affected by overnight incubation in 3 x 10(-5) M PGJ2. Phytohemagglutinin stimulation and natural killer activity of lymphocytes was reduced by PGJ2 and delta 12 PGJ2. Monocyte reactivity to 12-o-tetradecanoylphorbol-13-acetate, as assessed by chemiluminescence, was stimulated by preincubation of the cells for 1 h in 3 x 10(-5) M PGJ2 or delta 12 PGJ2. Such an augmentation was not exerted by PGD2.

Effects of some prostaglandins and leukotrienes on lymphocytes, monocytes and their activity in vitro.

The effect of some prostaglandins (PGs) and leukotrienes (LTs) on lymphocytes and monocytes was tested in vitro. Overnight incubation with PGD2 reduces the expression of Leu-2 antigen (suppressor/cytotoxic phenotype) and of Fc receptors for IgG. PGA2, PGD2 and to a lesser extent PGE2 inhibit PHA reactivity of lymphocytes. LTB4 does not have any inhibitory activity. Preincubation of lymphocytes with PGD2 and PGE2 decreases their NK activity. LTB4, but not the PGs tested, stimulates monocyte metabolism as assessed by chemiluminescence.

Cord blood T lymphocyte subpopulations in premature and full-term infants.

Cord blood lymphocyte preparations from premature and full-term infants were examined for T cell subsets using monoclonal antibodies. The number of T cells in relation to the total number of lymphocytes, the proportions of T helper (Th), and T suppressor (Ts) phenotypes, respectively, were the same in preterm infants of gestational age (GA) 26-36 weeks and term infants (GA 38-41) weeks). There was no correlation between GA and Th/Ts ratio. The relative number Ts was significantly lower in infants than in adult women.