CD14 C(-260)-->T polymorphism, plasma levels of the soluble endotoxin receptor CD14, their association with chronic infections and risk of stable coronary artery disease.

OBJECTIVES: We sought to investigate the association of CD14 genotype and plasma levels of soluble (s)CD14 with risk of stable coronary artery disease (CAD), chronic infections and sensitive markers of systemic inflammation. BACKGROUND: It has been suggested that genetic variation of the CD14 receptor with increased CD14 gene expression might play a role in atherogenesis. A mechanistic link would consist in its contribution to the inflammatory response seen in this disease. METHODS: We measured levels of sCD14 (microg/ml; ELISA) in 312 patients with angiographically proven CAD and stable angina pectoris, and in 477 age- and gender-matched healthy blood donors. CD14 genotype was determined by polymerase chain reaction. In addition, seropositivity to Chlamydia pneumoniae and Helicobacter pylori, a complete lipid profile and various sensitive systemic markers of inflammation were measured. RESULTS: CD14 C(-260)-->T genotype was not independently associated with increased risk of CAD after multivariable adjustments (odds ratio [OR] 1.34; 95% confidence interval [CI] 0.84 to 2.16). However, sCD14 plasma levels were higher in subjects with TT genotype compared with those with CT or CC genotype (p = 0.005). Plasma levels were not different between cases and controls (4.2 +/- 1.3 microg/ml vs. 4.3 +/- 1.3 microg/ml, p = NS). In multivariable logistic regression, the OR for the presence of CAD was 1.11 (95% CI, 0.65 to 1.91) if the top quintile of the sCD14 distribution was compared with the bottom quintile. There was no consistent association between seropositivity to either C. pneumoniae or H. pylori, or both, and sCD14 levels and between sCD14 levels or CD14 genotype and the various markers of inflammation. CONCLUSIONS: These results do not confirm an independent relationship between CD14 genotypes or plasma levels of sCD14 and risk of stable CAD in this population.

C-reactive protein as a predictor for incident diabetes mellitus among middle-aged men: results from the MONICA Augsburg cohort study, 1984-1998.

BACKGROUND: Previous studies have suggested that low-grade systemic inflammation is involved in the pathogenesis of type 2 diabetes mellitus. OBJECTIVE: To investigate the association between C-reactive protein (CRP), the classic acute-phase protein, and incident type 2 diabetes mellitus among middle-aged men. METHODS: A total of 2052 initially nondiabetic men aged 45 to 74 years who participated in 1 of the 3 MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Augsburg surveys between 1984 and 1995 were followed up for an average of 7.2 years. Incidence of diabetes was assessed by questionnaire mailed to participants in 1998. High-sensitive CRP was measured by an immunoradiometric assay. RESULTS: A total of 101 cases of incident diabetes occurred during the follow-up period. The age-standardized incidence rate was 6.9 per 1000 person-years. Men with CRP levels in the highest quartile (CRP > or = 2.91 mg/L) had a 2.7 times higher risk of developing diabetes (95% confidence interval, 1.4-5.2) compared with men in the lowest quartile (CRP < or = 0.67 mg/L) in a Cox proportional hazards model adjusted for age and survey. After further adjustment for body mass index, smoking, and systolic blood pressure, the observed association was significantly reduced and became nonsignificant. CONCLUSIONS: Low-grade systemic inflammation is associated with an increased risk of type 2 diabetes mellitus in middle-aged men. Inflammation could be one mechanism by which known risk factors for diabetes mellitus, such as obesity, smoking, and hypertension, promote the development of diabetes mellitus.

Third generation oral contraceptive use and cardiovascular risk factors.

OBJECTIVE: To analyze the relationship between third generation oral contraceptive (OC) use and various cardiovascular risk factors--including markers of inflammation--in a population-based sample. STUDY POPULATION AND METHODS: Data on OC use were obtained from women, aged 25-44 years participating in the MONICA Augsburg survey 1994-1995. Complete data were available from 841 women. Third generation OCs were defined as OCs containing desogestrel or gestodene, the remaining OC products were summarized in the group "other OC." RESULTS: Women taking third generation OCs had significantly higher C-reactive protein, fibrinogen, plasma viscosity, and HDL-cholesterol concentrations compared to the "other OC" group and non-users. In contrast, LDL-cholesterol was identical in the three groups. The analyses of interaction between smoking and OC use revealed that smoking women taking third generation pills had a less favourable pattern concerning inflammatory markers compared to women not on OC or using other products. CONCLUSION: Potentially harmful effects of OCs may arise from their positive association with the acute phase response. There is a close relationship with inflammatory markers in particular in women taking third generation OCs, which may, at least in part, contribute to the increased atherothrombotic risk, reported specifically in these women.

In vitro and ex vivo evidence for modulation of P-glycoprotein activity by progestins.

The well known gender-related differences in drug action may partly be explained by changes in activity and expression of drug metabolising enzymes, but also by modulation of active drug transport systems (e.g. P-glycoprotein, Pgp) by sexual steroids, which is yet not well investigated. Because many women are using hormones (e.g. as oral contraceptives) we investigated the influence of different synthetic progestins on Pgp activity. Pgp inhibition of progesterone, medroxyprogesterone, chlormadinone, cyproterone, levonorgestrel, norethisterone, desogestrel, and norgestimate was measured in vitro in two Pgp over-expressing cell lines (L-MDR1, P388/dx cells) and the corresponding parental cell lines by means of calcein assay, and ex vivo in human peripheral blood mononuclear cells (PBMCs) by rhodamine123 efflux. For most progestins tested, concentrations needed to double baseline fluorescence (f2) in L-MDR1 cells were similar to that of the potent Pgp inhibitor quinidine, whereas levonorgestrel and norethisterone did not reach f2. The results in P388/dx cells essentially confirmed our findings in L-MDR1 cells. Additionally, Pgp inhibitory activity of all progestins tested was also shown ex vivo in PBMCs. The potent Pgp inhibition by several synthetic progestins in vitro and ex vivo suggests that such an interaction might be clinically relevant despite generally low plasma concentrations of progestins. The results may be of particular importance for Pgp substrates, such as protease inhibitors and chemotherapeutic agents, for which intracellular concentrations are critical.

Independent association of various smoking characteristics with markers of systemic inflammation in men. Results from a representative sample of the general population (MONICA Augsburg Survey 1994/95).

AIMS: Aim of the study was to investigate the association between various markers of systemic inflammation and a detailed history of smoking in a large representative sample of the general population. METHODS AND RESULTS: The effects of chronic smoking on white blood cell (WBC) count, fibrinogen, albumin, plasma viscosity (PV), and high-sensitivity C-reactive protein (CRP) were measured in 2305 men and 2211 women, age 25-74 years, participating in the third MONICA Augsburg survey 1994/95. In men, current smokers showed statistically significantly higher values for WBC count, fibrinogen, PV, and CRP, compared to never smokers, with intermediate, but only slightly increased values for ex-smokers and for occasional smokers. No consistent associations were seen with albumin. Duration of smoking was positively associated with markers of inflammation as were pack-years of smoking. Conversely, duration of abstinence from smoking was inversely related to these markers. Except for WBC count, no such associations were found in women. CONCLUSION: Data from this large representative population show strong associations between smoking and various markers of systemic inflammation in men. They also show that cessation of smoking is associated with a decreased inflammatory response, which may represent one mechanism responsible for the reduced cardiovascular risk in these subjects.

Refinement of the association of serum C-reactive protein concentration and coronary heart disease risk by correction for within-subject variation over time: the MONICA Augsburg studies, 1984 and 1987.

The authors sought to assess the repeatability of measurements of C-reactive protein, an independent predictor of coronary heart disease, in a large cohort of apparently healthy men and to correct earlier estimates of the association of C-reactive protein and coronary heart disease for the measurement error in this protein. They measured C-reactive protein by a high-sensitivity assay in 936 men aged 45-64 years in the MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Augsburg cohort in 1984-1985 and remeasured it 3 years later. All men were subjected to an 8-year follow-up of their cardiovascular status. The analytical variation of the assay was small, with the analytical variance component at 1 percent of the within-subject variance component, a repeatability coefficient of 25 percent, and a reliability coefficient of 1.00. In contrast, the within-subject variation of C-reactive protein corresponded to a repeatability coefficient of 740 percent and a reliability coefficient of 0.54, indicating considerable within-subject variation. Based on the authors' estimates, three serial determinations of C-reactive protein should be done to achieve a reliability of 0.75, the value they found for total cholesterol. Correcting the hazard ratios in their original analysis of the association of coronary heart disease and high-sensitivity-assay C-reactive protein for the measurement error in C-reactive protein and covariables leads to a considerably larger estimate. The results suggest that the true association between C-reactive protein and cardiovascular risk is underestimated by a single C-reactive protein determination, and that several serial C-reactive protein measurements should be taken.

Markers of inflammation in women on different hormone replacement therapies.

BACKGROUND AND AIM: To measure inflammatory markers in postmenopausal women on different forms of hormone replacement therapy (HRT). METHOD: C-reactive protein (CRP), fibrinogen, plasma viscosity (PV), albumin and white blood cell (WBC) count were determined in 749 postmenopausal women. RESULTS: CRP concentration was significantly higher in women on estrogen monotherapy (difference of the median (d) 0.96 mg/l, P = 0.013), compared to those without HRT, but there was no difference in women on combined HRT. Fibrinogen concentration was significantly lower in women on estrogen monotherapy (d 0.25g/l, P = 0.004) and combined HRT (d 0.4 g/l, P < 0.001), compared to women without HRT. Similarly, PV was significantly lower in women on estrogen monotherapy (d 0.017 mPa x s, P = 0.007) and women on combined HRT (d 0.039mPa x s, P < 0.001), compared to those without HRT. No differences were found for WBC count and the negative acute phase marker albumin in the various treatment groups. In contrast to oral estrogen administration, levels of CRP, fibrinogen and PV in women on transdermal estrogen therapy did not differ from the no-HRT group. There was no association between these markers of inflammation and plasma estrogen levels. CONCLUSION: Oral estrogen monotherapy was associated with highest concentrations of CRP. In contrast, other markers of inflammation were either similar or lower in the oral HRT group, compared to the group of women without HRT, suggesting that higher CRP concentrations reflect estrogen effects on CRP expression rather than a systemic pro-inflammatory effect.

Oral contraception does not alter single dose saquinavir pharmacokinetics in women.

AIMS: Women experience more adverse drug reactions (ADR) to antiretroviral therapy than men. This may be attributed to higher plasma concentrations of protease inhibitors due to pharmacokinetic interactions with hormonal preparations. Thus, in the present study we aimed to investigate the influence of oral contraceptives (OC) on the pharmacokinetics of the protease inhibitor saquinavir. METHODS: Saquinavir was administered in a hard gelatin capsule formulation (Invirase) to rule out confounding by pharmaceutical aids of the more frequently used soft gelatin capsule. After an overnight fast, eight healthy female participants ingested a single oral dose of 600 mg saquinavir immediately before and after the 19th dose of a combined, low dose OC (0.03 mg ethinylestradiol, 0.075 mg gestodene) in a prospective, fixed sequence study design. The first saquinavir application was scheduled on day 1, 2, or 3 of the individual menstrual cycle. Plasma concentrations of saquinavir and relative concentrations of its M2&M3-hydroxy metabolites were determined by LC/MS/MS for 48 h. RESULTS: Intake of OC resulted in a significant decrease in morning serum concentrations (before intake of OC, compared to day 19 of OC therapy) of 17beta-estradiol by -23.4 pg ml-1 (57%, 95%CI: -76% to -37.4%); progesterone by -0.25 ng ml-1 (33%, 95%CI: -45.3% to -21.5%); follicle-stimulating hormone by -4.06 U l-1 (82%, 95%CI: -96.5% to -67.7%); and luteinizing hormone by -3.49 U l-1 (74%, 95%CI: -93 to -54.6%). Conversely, sexual hormone binding globulin serum concentrations increased by 83.6 nmol l-1 (205%, 95%CI: 32.2% to 377%). Pharmacokinetic parameters of saquinavir (AUC, Cmax, tmax, t1/2, CLR) were not affected by OC, nor was the relative metabolic ratio of saquinavir/M2&M3-hydroxy saquinavir. Furthermore, there was no association of serum hormone concentrations or MDR1-polymorphisms (C3435T and G2677T) with pharmacokinetic parameters of saquinavir. CONCLUSIONS: There was no effect of OC on saquinavir pharmacokinetics. Thus, pharmacokinetic interactions of synthetic sexual steroids with saquinavir are not likely to account for the increased ADR to antiretroviral therapy seen in women.

Pharmacokinetic interaction of chloroquine and methylene blue combination against malaria.

OBJECTIVE: The combination of chloroquine and methylene blue is potentially effective for the treatment of chloroquine-resistant malaria caused by Plasmodium falciparum. The aim of this study was to investigate whether methylene blue influences the pharmacokinetics of chloroquine. METHODS: In a randomized, placebo-controlled, parallel group design, a 3-day course of therapeutic oral doses of chloroquine (total 2.5 g in male, 1.875 g in female participants) with oral co-administration of placebo or 130 mg methylene blue twice daily for 3 days was administered to 24 healthy individuals. Chloroquine, desethylchloroquine, and methylene blue concentrations were determined by means of HPLC/UV or LC/MS/MS assays in whole blood, plasma, and urine for 28 days after the last dose. RESULTS: During methylene blue exposure, the area under the chloroquine whole blood concentration-time curve normalized to body weight (AUC(0-24 h)/BW) yielded a trend of reduction (249+/-98.2 h mug l(-1) kg(-1) versus 315+/-65.0 h mug l(-1) kg(-1), P=0.06). The AUC(0-24 h)/BW of desethylchloroquine was reduced by 35% (104+/-40.3 h mug l(-1) kg(-1) versus 159+/-66.6 h mug l(-1) kg(-1), P=0.03), whereas the metabolic ratio between chloroquine and desethylchloroquine remained unchanged (2.25+/-0.49 versus 1.95+/-0.42, P=0.17). The renal clearance of chloroquine and the ratio between chloroquine in whole blood and plasma remained unchanged (P>0.1). CONCLUSION: Oral co-administration of methylene blue appears to result in a small reduction of chloroquine exposure which is not expected to be clinically relevant and thus represents no concern for further development as an anti-malarial combination.