Adiposity and Smoking Mediate the Relationship Between Depression History and Inflammation Among Young Adults.

BACKGROUND: Depression is associated with inflammation, but the mechanisms underlying this association are unclear. We examined adiposity and smoking as potential pathways through which childhood depression may lead to an elevated inflammatory status among young adults. METHODS: The sample included 294 subjects with histories of depression (probands), 270 never-depressed siblings of probands (high-risk siblings), and 169 controls. C-reactive protein (CRP), interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1 (sICAM-1) were assessed in serum samples. An adiposity score was computed from body mass index and waist circumference. Smoking behavior was evaluated during an interview. Mixed-effects models were used to test whether adiposity and smoking mediate the relationship between depression and inflammation. RESULTS: Probands (p = .004), but not siblings (p = .071), had higher levels of sICAM-1 compared to controls. However, depression history and risk status had no direct effects on CRP (ps > .13) or IL-6 (ps > .16). Importantly, adiposity indirectly mediated the effect of group (probands vs. controls; siblings vs. controls) on all three inflammatory markers. Smoking indirectly mediated the effect of group (probands vs. controls; siblings vs. controls) on sICAM-1 only. CONCLUSIONS: Among young adults, the adverse inflammatory consequences of depression history are significant for sICAM-1. Adiposity and smoking are pathways through which depression can indirectly impact several inflammatory markers, suggesting possible preventive interventions to improve the immunologic and cardiovascular health of depression-prone individuals.

Is Magnetic Resonance Imaging Detection of Kidney Iron Deposition Increased in Haptoglobin 2-2 Genotype Carriers with Type 1 Diabetes?

Haptoglobin's (Hp) main role is to bind free hemoglobin (Hb), reducing its oxidative potential. The Hp-Hb complex formed is cleared from the circulation by macrophage receptor CD163. In diabetes, impaired Hp 2-2-Hb CD163 clearance and abnormal glomerular permeability allow the large Hp 2-2-Hb complex to cross the barrier, where its redox active iron leads to cellular toxicity. Although Hp 2-2 predicts renal function decline, whether renal iron deposition differs by Hp is unknown. We used renal quantitative T2* magnetic resonance imaging to estimate iron level in the cortex and medullar of type 1 diabetes (T1D) adults [15 Hp 1-1 and 15 Hp 2-2 carriers of similar age (53 years), duration (45 years), and gender]. Total kidney iron level was estimated as the sum of the cortex and medullar iron. Albuminuria was defined as urinary albumin to creatinine ratio >30 mg/g in two of three samples. Total kidney iron did not differ by gender or Hp but was higher in those with albuminuria (p = 0.05), an association confined to Hp 2-2 carriers (p = 0.04 vs. p = 0.51 in Hp 1-1). These data lead to the hypothesis that kidney iron deposition is increased among Hp 2-2 carriers with albuminuria in T1D. Antioxid. Redox Signal. 29, 735-741.

A Significant Positive Association of Vitamin D Deficiency with Coronary Artery Calcification among Middle-aged Men: For the ERA JUMP Study.

OBJECTIVE: Although a significant positive association of vitamin D deficiency with coronary heart disease has been demonstrated in cross-sectional as well as prospective studies, only a few studies have examined the association of vitamin D deficiency with subclinical atherosclerosis. We examined whether vitamin D deficiency is associated with subclinical atherosclerosis, as measured by coronary artery calcification (CAC) in asymptomatic adults. METHODS: In a population-based cross-sectional study, 195 men aged 40 to 49 years without cardiovascular disease were randomly selected (98 Caucasian and 97 Japanese American men). Liquid chromatography-tandem mass spectrometry was utilized to measure serum vitamin D. CAC was examined by electron beam computed tomography using standardized protocols and read centrally at the University of Pittsburgh using Agatston's methods. To investigate an association between vitamin D deficiency (defined as 25-hydroxyvitamin D [25(OH)D] < 20 ng/mL) and CAC (defined as Agatston score ≥ 10), we utilized multivariable logistic regression models. RESULTS: Prevalence of CAC and vitamin D deficiency was 27.2% and 10.3%, respectively. Participants with CAC were significantly older, had significantly higher body mass index (BMI), and had higher rates of smoking. Those with CAC were 3.31 times likely to be vitamin D deficient, after adjusting for traditional cardiovascular risk factors (odds ratio [OR] = 3.31, 95% confidence interval [CI], 1.12-9.77). CONCLUSIONS: In this population-based study of healthy middle-aged men, vitamin D deficiency had a significant positive association with the presence of CAC.

The association between maternal antioxidant levels in midpregnancy and preeclampsia.

OBJECTIVE: We sought to determine whether midpregnancy antioxidant levels are associated with preeclampsia, overall and by timing of onset. STUDY DESIGN: We carried out a case-control study, nested within a cohort of 5337 pregnant women in Montreal, Quebec, Canada. Blood samples obtained at 24-26 weeks were assayed for nonenzymatic antioxidant levels among cases of preeclampsia (n = 111) and unaffected controls (n = 441). We excluded women diagnosed with gestational hypertension only. We used logistic regression with the z-score of each antioxidant level as the main predictor variable for preeclampsia risk. We further stratified early-onset (<34 weeks) and late-onset preeclampsia and carried out multinomial logistic regression. Finally, we assessed associations between antioxidant biomarkers and timing of onset (in weeks) by Cox regression, with appropriate selection weights. We summed levels of correlated biomarkers (r(2) > 0.3) and log-transformed positively skewed distributions. We adjusted for body mass index, nulliparity, preexisting diabetes, hypertension, smoking, and proxies for ethnicity and socioeconomic status. RESULTS: The odds ratios for α-tocopherol, α-tocopherol:cholesterol, lycopene, lutein, and carotenoids (sum of α-carotene, ß-carotene, anhydrolutein, α-cryptoxanthin, and ß-cryptoxanthin) suggested an inverse association between antioxidant levels and overall preeclampsia risk; however, only lutein was significantly associated with overall preeclampsia in adjusted models (odds ratio, 0.60; 95% confidence interval, 0.46-0.77) per SD. In multinomial logistic models, the relative risk ratio (RRR) estimates for the early-onset subgroup were farther from the null than those for the late-onset subgroup. The ratio of α-tocopherol to cholesterol and retinol were significantly associated with early- but not late-onset preeclampsia: RRRs (95% confidence intervals) for early-onset preeclampsia 0.67 (0.46-0.99) and 1.61 (1.12-2.33), respectively. Lutein was significantly associated with both early- and late-onset subtypes in adjusted models; RRRs 0.53 (0.35-0.80) and 0.62 (0.47-0.82), respectively. Survival analyses confirmed these trends. CONCLUSION: Most antioxidants were more strongly associated with early-onset preeclampsia, suggesting that oxidative stress may play a greater role in the pathophysiology of early-onset preeclampsia. Alternatively, reverse causality may explain this pattern. Lutein was associated with both early- and late-onset preeclampsia and may be a promising nutrient to consider in preeclampsia prevention trials, if this finding is corroborated.

Does the Concentration of Oxidative and Inflammatory Biomarkers Differ by Haptoglobin Genotype in Type 1 Diabetes?

The haptoglobin (Hp) 2 allele directly predicts coronary artery disease in type 1 diabetes, potentially due to its decreased antioxidative/anti-inflammatory properties. We measured the concentrations of oxidative/inflammatory biomarkers (urinary 15-isoprostane F(2t) [IsoP], α- and γ-tocopherol, tumor necrosis factor α [TNF-α], high-sensitivity C-reactive protein [hsCRP], white blood cell [WBC] count, fibrinogen, and adiponectin) thrice during 20 years of follow-up among 454 individuals with childhood-onset type 1 diabetes (mean baseline age, 28 years and diabetes duration, 19 years). Differences in biomarkers by Hp were assessed both at baseline (i.e., the first time point of measurements) and over time (with mixed models). No differences by Hp were observed at baseline with the exception of a significant trend toward higher IsoP concentrations with the number of Hp 2 alleles (p=0.01). In multivariable mixed models, the concentrations of IsoP (ß=0.05, p=0.01) and WBC count (ß=0.20, p=0.06) overtime increased incrementally with the number of Hp 2 alleles. No other biomarker assessed related to Hp. Reported elevated IsoP and WBC count concentrations over time among Hp 2 allele carriers lead to the hypothesis that the antioxidative and anti-inflammatory capacity of the Hp 2 is inferior to that of the Hp 1 allele in type 1 diabetes.

Lipoprotein particles and size, total and high molecular weight adiponectin, and leptin in relation to incident coronary heart disease among severely obese postmenopausal women: The Women's Health Initiative Observational Study.

BACKGROUND: We hypothesized that higher concentrations of LDL particles (LDL-P) and leptin, and lower concentrations of HDL particles (HDL-P), and total and high molecular weight (HMW) adiponectin, would predict incident coronary heart disease (CHD) among severely obese postmenopausal women. METHODS: In a case-cohort study nested in the Women's Health Initiative Observational Study, we sampled 677 of the 1852 white or black women with body mass index (BMI) ≥40 kg/m2 and no prevalent cardiovascular disease (CVD), including all 124 cases of incident CHD over mean 5.0 year follow-up. Biomarkers were assayed on stored blood samples. RESULTS: In multivariable-adjusted weighted Cox models, higher baseline levels of total and small LDL-P, and lower levels of total and medium HDL-P, and smaller mean HDL-P size were significantly associated with incident CHD. In contrast, large HDL-P levels were inversely associated with CHD only for women without diabetes, and higher total and HMW adiponectin levels and lower leptin levels were associated with CHD only for women with diabetes. Higher total LDL-P and lower HDL-P were associated with CHD risk independently of confounders including CV risk factors and other lipoprotein measures, with adjusted HR (95%CIs) of 1.55(1.28, 1.88) and (0.70 (0.57, 0.85), respectively, and similar results for medium HDL-P. CONCLUSIONS: Higher CHD risk among severely obese postmenopausal women is strongly associated with modifiable concentrations of LDL-P and HDL-P, independent of diabetes, smoking, hypertension, physical activity, BMI and waist circumference. GENERAL SIGNIFICANCE: Severely obese postmenopausal women should be considered high risk candidates for lipid lowering therapy.

Chronic activation of FXR in transgenic mice caused perinatal toxicity and sensitized mice to cholesterol toxicity.

The nuclear receptor farnesoid X receptor (FXR) (nuclear receptor subfamily 1, group H, member 4, or NR1H4) is highly expressed in the liver and intestine. Previous reports have suggested beneficial functions of FXR in the homeostasis of bile acids, lipids, and glucose, as well as in promoting liver regeneration and inhibiting carcinogenesis. To investigate the effect of chronic FXR activation in vivo, we generated transgenic mice that conditionally and tissue specifically express the activated form of FXR in the liver and intestine. Unexpectedly, the transgenic mice showed several intriguing phenotypes, including partial neonatal lethality, growth retardation, and spontaneous liver toxicity. The transgenic mice also displayed heightened sensitivity to a high-cholesterol diet-induced hepatotoxicity but resistance to the gallstone formation. The phenotypes were transgene specific, because they were abolished upon treatment with doxycycline to silence the transgene expression. The perinatal toxicity, which can be rescued by a maternal vitamin supplement, may have resulted from vitamin deficiency due to low biliary bile acid output as a consequence of inhibition of bile acid formation. Our results also suggested that the fibroblast growth factor-inducible immediate-early response protein 14 (Fn14), a member of the proinflammatory TNF family, is a FXR-responsive gene. However, the contribution of Fn14 induction in the perinatal toxic phenotype of the transgenic mice remains to be defined. Because FXR is being explored as a therapeutic target, our results suggested that a chronic activation of this nuclear receptor may have an unintended side effect especially during the perinatal stage.

Associations between Inflammatory Markers and Subclinical Atherosclerosis in Middle-aged White, Japanese-American and Japanese Men: The ERA-JUMP Study.

AIM: To examine whether the inflammatory markers C-reactive protein (CRP) and fibrinogen are associated with biomarkers of atherosclerosis [carotid intima-media thickness (IMT) and coronary artery calcification (CAC)] in the general male population, including Asians. METHODS: Population-based samples of 310 Japanese, 293 Japanese-American and 297 white men 40-49 years of age without clinical cardiovascular disease underwent measurement of IMT, CAC and the CRP and fibrinogen levels as well as other conventional risk factors using standardized methods. Statistical associations between the variables were evaluated using multiple linear or logistic regression models. RESULTS: The Japanese group had significantly lower levels of inflammatory markers and subclinical atherosclerosis than the Japanese-American and white groups (P-values all ＜0.001). The mean level of CRP was 0.66 vs. 1.11 and 1.47 mg/L, while that of fibrinogen was 255.0 vs. 313.0 and 291.5 mg/dl, respectively. In addition, the mean carotid IMT was 0.61 vs. 0.73 and 0.68 mm, while the mean prevalence of CAC was 11.6% vs. 32.1% and 26.3%, respectively. Body mass index (BMI) showed significant positive associations with both the CRP and fibrinogen levels. Although CRP showed a significant positive association with IMT in the Japanese men, this association became non-significant following adjustment for traditional risk factors or BMI. In all three populations, CRP was not found to be significantly associated with the prevalence of CAC. Similarly, fibrinogen did not exhibit a significant association with either IMT or the prevalence of CAC. CONCLUSIONS: The associations between inflammatory markers and subclinical atherosclerosis may merely reflect the strong associations between BMI and the levels of inflammatory markers and incidence of subclinical atherosclerosis in both Eastern and Western populations.

Regional pulse wave velocities and their cardiovascular risk factors among healthy middle-aged men: a cross-sectional population-based study.

BACKGROUND: Both carotid-femoral (cf) pulse wave velocity (PWV) and brachial-ankle (ba) PWV employ arterial sites that are not consistent with the path of blood flow. Few previous studies have reported the differential characteristics between cfPWV and baPWV by simultaneously comparing these with measures of pure central (aorta) and peripheral (leg) arterial stiffness, i.e., heart-femoral (hf) PWV and femoral-ankle (fa) PWV in healthy populations. We aimed to identify the degree to which these commonly used measures of cfPWV and baPWV correlate with hfPWV and faPWV, respectively, and to evaluate whether both cfPWV and baPWV are consistent with either hfPWV or faPWV in their associations with cardiovascular (CV) risk factors. METHODS: A population-based sample of healthy 784 men aged 40-49 (202 white Americans, 68 African Americans, 202 Japanese-Americans, and 282 Koreans) was examined in this cross-sectional study. Four regional PWVs were simultaneously measured by an automated tonometry/plethysmography system. RESULTS: cfPWV correlated strongly with hfPWV (r = .81, P < .001), but weakly with faPWV (r = .12, P = .001). baPWV correlated moderately with both hfPWV (r = .47, P < .001) and faPWV (r = .62, P < .001). After stepwise regression analyses with adjustments for race, cfPWV shared common significant correlates with both hfPWV and faPWV: systolic blood pressure (BP) and body mass index (BMI). However, BMI was positively associated with hfPWV and cfPWV, and negatively associated with faPWV. baPWV shared common significant correlates with hfPWV: age and systolic BP. baPWV also shared the following correlates with faPWV: systolic BP, triglycerides, and current smoking. CONCLUSIONS: Among healthy men aged 40 - 49, cfPWV correlated strongly with central PWV, and baPWV correlated with both central and peripheral PWVs. Of the CV risk factors, systolic BP was uniformly associated with all the regional PWVs. In the associations with factors other than systolic BP, cfPWV was consistent with central PWV, while baPWV was consistent with both central and peripheral PWVs.

Do differences in risk factors explain the lower rates of coronary heart disease in Japanese versus U.S. women?

BACKGROUND: Mortality from coronary heart disease (CHD) in women in Japan is one of the lowest in developed countries. In an attempt to shed some light on possible reasons of lower CHD in women in Japan compared with the United States, we extensively reviewed and analyzed existing national data and recent literature. METHODS: We searched recent epidemiological studies that reported incidence of acute myocardial infarction (AMI) and examined risk factors for CHD in women in Japan. Then, we compared trends in risk factors between women currently aged 50-69 years in Japan and the United States, using national statistics and other available resources. RESULTS: Recent epidemiological studies have clearly shown that AMI incidence in women in Japan is lower than that reported from other countries, and that lipids, blood pressure (BP), diabetes, smoking, and early menopause are independent risk factors. Comparing trends in risk factors between women in Japan and the United States, current levels of serum total cholesterol are higher in women in Japan and levels have been similar at least since 1990. Levels of BP have been higher in in Japan for the past 3 decades. Prevalence of type 2 diabetes has been similar in Japanese and white women currently aged 60-69 for the past 2 decades. In contrast, rates of cigarette smoking, although low in women in both countries, have been lower in women in Japan. CONCLUSIONS: Differences in risk factors and their trends are unlikely to explain the difference in CHD rates in women in Japan and the United States. Determining the currently unknown factors responsible for low CHD mortality in women in Japan may lead to new strategy for CHD prevention.

A cross-sectional association of obesity with coronary calcium among Japanese, Koreans, Japanese Americans, and U.S. whites.

AIMS: Conflicting evidence exists regarding whether obesity is independently associated with coronary artery calcium (CAC), a measure of coronary atherosclerosis. We examined an independent association of obesity with prevalent CAC among samples of multi-ethnic groups whose background populations have varying levels of obesity and coronary heart disease (CHD). METHODS AND RESULTS: We analysed a population-based sample of 1212 men, aged 40-49 years free of clinical cardiovascular disease recruited in 2002-06; 310 Japanese in Japan (JJ), 294 Koreans in South Korea (KN), 300 Japanese Americans (JA), and 308 Whites in the USA (UW). We defined prevalent CAC as an Agatston score of ≥10. Prevalent CAC was calculated by tertile of the body mass index (BMI) in each ethnic group and was plotted against the corresponding median of tertile BMI. Additionally, logistic regression was conducted to examine whether an association of the BMI was independent of conventional risk factors. The median BMI and crude prevalence of CAC for JJ, KN, JA, and UW were 23.4, 24.4, 27.4, and 27.1 (kg/m2); 12, 11, 32, and 26 (%), respectively. Despite the absolute difference in levels of BMI and CAC across groups, higher BMI was generally associated with higher prevalent CAC in each group. After adjusting for age, smoking, alcohol, hypertension, lipids, and diabetes mellitus, the BMI was positively and independently associated with prevalent CAC in JJ, KN, UW, but not in JA. CONCLUSION: In this multi-ethnic study, obesity was independently associated with subclinical stage of coronary atherosclerosis among men aged 40-49 years regardless of the BMI level.

Longitudinal effects of weight loss and regain on cytokine concentration of obese adults.

OBJECTIVE: To describe patterns of weight loss and regain and their effect on the pro-inflammatory cytokines IL-6 and TNF-α, and anti-inflammatory cytokines adiponectin and IL-10 during a 24-month weight loss trial. MATERIALS/METHODS: Participants were obese adults (N=66) who lost and regained ≥ 10lb during a 24-month clinical trial of behavioral weight loss treatment. Measurements of cytokines and weight were conducted at baseline, 6, 12, 18, and 24 months. Linear mixed modeling was used to determine percent change in weight and cytokines from baseline. RESULTS: The sample was predominantly female (80.3%) and White (86.4%), with a mean age of 48.4 ± 7.3 years and mean BMI of 34.5 ± 4.4 kg/m(2). At baseline, men had higher waist circumference, body weight, and energy intake, and lower percent body fat and adiponectin. The largest decrease in weight was observed at 6 months with a mean 11% decrease (p<.0001).A significant gender-by-weight change interaction on percent change in adiponectin was observed [b(se)=0.9 (0.2), p=.0003], with men having a larger increase in adiponectin with weight loss compared to women. There was a significant effect of weight gain over time with increases in IL-6 [b(se)=0.9 (0.3), p=.001]. CONCLUSIONS: Overall, weight loss was significantly associated with improvements in adiponectin and IL-6. Those improvements remained at 24 months, following weight regain. The association between weight change and adiponectin was different between genders. Implementing strategies that support sustained weight loss can help prevent a state of chronic systemic inflammation and its associated adverse effects.

Erythrocyte omega-6 and omega-3 fatty acids and mammographic breast density.

Diets low in omega-6 (n-6) polyunsaturated fatty acids (PUFAs) and high in omega-3 (n-3) PUFAs may protect against breast cancer development. Associations of PUFA intake with mammographic density, an intermediate marker of breast cancer risk, have been inconsistent; however, prior studies have relied on self-reported dietary PUFA intake. We examined the association between circulating erythrocyte n-6 and n-3 PUFAs with mammographic density in 248 postmenopausal women who were not taking exogenous hormones. PUFAs in erythrocytes were measured by gas-liquid chromatography, and mammographic density was assessed quantitatively by planimetry. Spearman's correlation coefficients and generalized linear models were used to evaluate the relationships between PUFA measures and mammographic density. None of the erythrocyte n-6 or n-3 PUFA measures were associated with percent density or dense breast area.

Evidence for a genetic link between bone and vascular measures in African ancestry families.

Bone mineral density (BMD) has been inversely associated with subclinical and clinical cardiovascular disease (CVD) in population studies, but the potential mechanisms underlying this relationship are unclear. To test if there is a genetic basis underlying this association, we determined the phenotypic and genetic correlations between BMD and carotid artery ultrasound measures in families. Dual-energy X-ray absorptiometry and peripheral quantitative computed tomography were used to measure BMD in 461 individuals with African ancestry belonging to seven large, multigenerational families (mean family size 66; 3414 total relative pairs). Carotid artery ultrasound was used to measure adventitial diameter (AD) and intima-media thickness (IMT). Phenotypic and genetic correlations between BMD and carotid measures were determined using pedigree-based maximum likelihood methods. We adjusted for potential confounding factors, including age, sex, body weight, height, menopausal status, smoking, alcohol intake, walking for exercise, diabetes, hypertension, serum lipid and lipoprotein levels, inflammation markers, and kidney function. We found statistically significant phenotypic (ρ = -0.19) and genetic (ρG = -0.70) correlations (p < 0.05 for both) between lumbar spine BMD and AD in fully adjusted models. There was also a significant genetic correlation between trabecular BMD at the radius and IMT in fully adjusted models (ρG = -0.398; p < 0.05). Our findings indicate that the previously observed association between osteoporosis and CVD in population-based studies may be partly mediated by genetic factors and that the pleiotropic effects of these genes may operate independently of traditional risk pathways.

The prevalence of aortic calcification in Japanese compared to white and Japanese-American middle-aged men is confounded by the amount of cigarette smoking.

BACKGROUND: The prevalence of coronary artery calcification (CAC) in Japanese men is lower than in white and Japanese-American men. It is unclear if aortic calcification (AC) strongly linked to smoking is also lower in Japanese men who have many times higher smoking prevalence compared to US men. METHODS: We conducted a population-based study of 903 randomly-selected men aged 40-49 years: 310 Japanese men in Kusatsu, Japan, 301 white men in Allegheny County, US, and 292 Japanese men in Hawaii, US (2002-2006). The presence of AC was assessed by electron-beam tomography. AC was defined as Agatston aortic calcium scores (AoCaS) >0 and ≥ 100. RESULTS: Japanese (35.8%) had significantly less AoCaS>0 compared to both white (68.8%, p<0.001) and Japanese-American (62.3%, p<0.001) but similar AoCaS ≥ 100 (19.4%, 18.3%, 22.6%, respectively, p=0.392). The pack-years of smoking, which was highest in Japanese, was the most important single associate of AC in all populations. Additionally age, low-density-lipoprotein cholesterol (LDL-C), and triglycerides in Japanese; body-mass index (BMI) in white; and BMI, LDL-C, hypertension, diabetes, and lipid medications in Japanese-American were independent associates of AC. The risk of AC using either cut points adjusted for pack-years of smoking and additional risk factors was lower in Japanese compared to both white and Japanese-American. AC and CAC had moderately positive and significant correlations in Japanese (r=0.26), white (r=0.39), and Japanese-American (r=0.45). CONCLUSIONS: The prevalence of AC defined both >0 and ≥ 100 was significantly lower in Japanese than in white and Japanese-American men after adjusting for cigarette smoking and additional risk factors.

Chronic kidney disease and estimates of kidney function in HIV infection: a cross-sectional study in the multicenter AIDS cohort study.

BACKGROUND: Cystatin C has been proposed as an alternative marker of kidney function among HIV-infected persons in whom serum creatinine is affected by extrarenal factors. METHODS: In this cross-sectional study, we compared estimated glomerular filtration rates (eGFR) using serum creatinine versus cystatin C between 150 HIV-uninfected and 783 HIV-infected men. We evaluated the prevalence of chronic kidney disease (CKD; eGFR less than 60 mL/min/1.73 m) and examined the influence of extrarenal factors on GFR estimates among HIV-infected men. RESULTS: Estimated GFRSCR was similar by HIV serostatus, but eGFRCYSC was lower in HIV-infected men. A higher proportion of HIV-infected men were classified as having CKD when using eGFRCYSC versus eGFRSCR (7% vs 5%, P < 0.01). In HIV-infected individuals without CKD, eGFRSCR was higher than eGFRCYSC, whereas it was lower than eGFRCYSC in persons with CKD. In HIV-infected men, older age, proteinuria, and prior clinical AIDS were inversely associated with both GFR estimates. Higher serum albumin levels and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use were associated with lower eGFRSCR. HIV viral load, hepatitis C coinfection, and serum alkaline phosphatase were inversely associated with eGFRCYSC. CONCLUSION: Among HIV-uninfected and HIV-infected men of similar social risk behaviors, GFR estimates differed by biomarker and kidney function level. Estimated GFRCYSC classified a larger proportion of HIV-infected men with CKD compared with eGFRSCR. Differences between these GFR-estimating methods may be the result of the effects of extrarenal factors on serum creatinine and cystatin C. Until GFR-estimating equations are validated among HIV-infected individuals, current GFR estimates based on these biomarkers should be interpreted with care in this patient population.

Markers of inflammation are heritable and associated with subcutaneous and ectopic skeletal muscle adiposity in African ancestry families.

UNLABELLED: Abstract Background: Skeletal muscle adipose tissue (AT) infiltration, or myosteatosis, appears to be greater in African compared with European ancestry individuals and may play a role in type 2 diabetes mellitus (T2DM), a disease that disproportionally affects African ancestry populations. Inflammation is one mechanism that may link myosteatosis with increased T2DM risk, but studies examining the relationship between inflammation and myosteatosis are lacking. METHODS: To examine these associations, we measured skeletal muscle subcutaneous AT, intermuscular AT, and skeletal muscle density using quantitative computed tomography and serum markers of inflammation in 471 individuals from 8 Afro-Caribbean multigenerational families [mean family size 67; mean age 43 years; mean body mass index (BMI) 28 kg/m(2)]. RESULTS: After removing the variation attributable to significant covariates, heritabilities of inflammation markers [C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)] ranged from 33% (TNFα) to 40% (CRP); all P<0.01. Higher CRP, IL-6, and TNF-α were associated with lower subcutaneous AT around skeletal muscle (r=-0.13 to -0.19, P<0.05). Higher CRP was additionally associated with lower skeletal muscle density, indicative of greater intramuscular AT (r=-0.10, P<0.05), hyperinsulinemia (r=0.12, P<0.05), and increased homeostasis model assessment of insulin resistance (HOMA-IR) (r=0.17, P<0.01). CONCLUSIONS: Our findings suggest that heredity may play a significant role in the determination of several markers of inflammation in African ancestry individuals. Higher concentrations of CRP appear to be associated with greater skeletal muscle AT infiltration, lower subcutaneous AT, hyperinsulinemia, and insulin resistance. Longitudinal studies are needed to further evaluate the relationship between inflammation with changes in skeletal muscle AT distribution with aging and the incidence of T2DM.

Circulating levels of 8 cytokines and marine n-3 fatty acids and indices of obesity in Japanese, white, and Japanese American middle-aged men.

This study examines the differences in circulating levels of cytokines among Japanese in Japan (JJ), Japanese Americans (JA), and whites and their associations with obesity and marine n-3 fatty acids (FA) in a cross-sectional population-based study of 297 men aged 40-49 (100 JJ, 99 whites, and 98 JA). Experimental studies show that cytokines are associated with obesity positively and marine n-3 FA inversely. Serum interleukin-1alpha (IL-1alpha), IL-1 receptor agonist (IL-1ra), IL-4, IL-8, IL-10, inducible protein-10 (IP-10), tumor necrosis factor-alpha (TNF-alpha), monocyte chemoattractant protein-1 (MCP-1), and marine n-3 FA were determined. Body mass index (BMI), waist circumference, and computed tomography-measured visceral and subcutaneous adipose tissues were determined. The JJ had significantly lower levels of IL-1alpha, IL-4, IL-8, MCP-1, and TNF-alpha than whites and JA. Whites and JA had similar levels of IL-1alpha, IL-4, and IL-8 whereas whites had significantly higher levels of MCP-1 and TNF-alpha than JA. The JJ were least obese (BMI (kg/m(2)), mean +/- standard deviation) 23.6 +/- 2.8, 27.9 +/- 4.6, and 27.9 +/- 4.5 for JJ, whites, and JA, respectively. The JJ had marine n-3 FA about 100% higher than whites and JA (serum marine n-3 FA (%), median (interquartile range) 8.79 (7.41, 11.16), 3.47 (2.63, 4.83), and 4.44 (3.33, 6.01) for JJ, whites, and JA, respectively). Generally cytokines had weak and nonsignificant associations with indices of obesity and nonsignificant associations with marine n-3 FA. BMI had significant inverse associations with IL-1alpha, IL-4, and IL-8 in JA (P < 0.05). Marine n-3 FA had marginally significant inverse associations with IL-8 in JJ (P = 0.055) and TNF-alpha in whites (P = 0.076). The JJ had lower levels of many cytokines than whites and JA. Generally cytokines had weak and nonsignificant associations with indices of obesity and marine n-3 FA. Further investigation is needed to determine why JJ had lower circulating levels of cytokines.

Serum n-6 fatty acids and lipoprotein subclasses in middle-aged men: the population-based cross-sectional ERA-JUMP study.

BACKGROUND: The associations of serum omega-6 (n-6) fatty acids with lipoprotein subclasses at the population level are uncertain. OBJECTIVE: We aimed to examine associations between major n-6 fatty acids [ie, linoleic acid (LA, 18:2n-6) and arachidonic acid (AA, 20:4n-6)] and the lipoprotein subclasses VLDL, LDL, and HDL. DESIGN: We conducted a cross-sectional study in 1098 participants using population-based data from US white, Japanese American, Japanese, and Korean men aged 40-49 y. Serum fatty acids were analyzed by capillary gas-liquid chromatography. Lipoprotein subclasses were measured by nuclear magnetic resonance spectroscopy. Multiple linear regression models as a function of each fatty acid were used after adjustment for age, population, body mass index, pack-years of smoking, alcohol consumption, diabetes, hypertension, and omega-3 (n-3) and trans fatty acids. RESULTS: Serum LA was inversely associated with large VLDL (beta = -0.62, P < 0.001), total LDL (beta = -22.08, P < 0.001), and small LDL (beta = -31.89, P < 0.001) particle concentrations and VLDL size (beta = -0.72, P < 0.001). Serum LA was positively associated with large HDL particle concentration (beta = 0.21, P < 0.001) and HDL size (beta = 0.03, P < 0.001). The patterns of association of AA with large VLDL and large HDL particle concentrations were comparable with those of LA. CONCLUSIONS: At the population level, higher serum concentrations of LA were significantly associated with lower concentrations of total LDL particles. Higher serum concentrations of LA and AA were significantly associated with a lower concentration of large VLDL particles and a higher concentration of large HDL particles. These associations were consistent across the population groups. This trial was registered at clinicaltrials.gov as NCT00069797.

Visceral and subcutaneous adiposity and adiponectin in middle-aged Japanese men: the ERA JUMP study.

Adiponectin is reduced in obesity and has been suggested to play an important role in modulation of atherosclerosis. We studied the relationship between visceral (VAT) and subcutaneous (SAT) adipose tissue and serum adiponectin concentrations in Japanese men. Participants were 304 randomly selected community-based Japanese men aged 40-49 without a prior history of cardiovascular disease. Participants were grouped according to tertiles of serum adiponectin. In multiple linear regression analysis including age, pack years of smoking, and alcohol intake as covariates, log-transformed adiponectin was inversely associated with both VAT and SAT when these two obesity measures were included separately in the models. However, log-transformed adiponectin was inversely associated with VAT (standardized beta estimate=-0.465; P<0.0001) and positively associated with SAT (standardized beta estimate=1.277; P=0.03), when these were included concomitantly in the model. In conclusion, VAT and SAT had differential associations with serum adiponectin concentrations.