Association of Serum Carotenoid Levels With Urinary Albumin Excretion in a General Japanese Population: The Yakumo Study

Abstract

BackgroundAlbuminuria is a risk factor for not only nephropathy progression but also cardiovascular disease. Oxidative stress may have a role in the positive association between albuminuria and cardiovascular disease.MethodsThis cross-sectional study investigated the associations of serum levels of carotenoids, which are dietary antioxidants, with albuminuria among 501 Japanese adults (198 men, mean age ± SD: 66.4 ± 10.0 years; 303 women, mean age ± SD: 65.4 ± 9.8 years) who attended a health examination. Serum levels of carotenoids were determined by high-performance liquid chromatography. Logistic regression analysis was used to estimate odds ratios (ORs) with 95% CIs for albuminuria after adjustment for age, body mass index, smoking habits, drinking habits, hypertension, diabetes mellitus, and dyslipidemia.ResultsPrevalence of albuminuria was 15.4% among men and 18.1% among women. Among women with albuminuria, geometric mean serum levels of canthaxanthin, lycopene, β-carotene, total carotenes, and provitamin A were significantly lower than those of normoalbuminuric women. Adjusted ORs for albuminuria among women in the highest tertiles of serum β-carotene (OR, 0.45; 95% CI, 0.20–0.98) and provitamin A (OR, 0.45; 95% CI, 0.20–0.97) were significantly lower as compared with those for women in the lowest tertile. There were no associations between serum carotenoids and albuminuria in men.ConclusionsAn increased level of serum provitamin A, especially serum β-carotene, was independently associated with lower risk of albuminuria among Japanese women.

Association of subcutaneous and visceral fat with circulating microRNAs in a middle-aged Japanese population

“…Health examinations of inhabitants aged 5 39 years have been performed in an area of Hokkaido, Japan since 1982. [26][27][28] Cross-sectional and longitudinal studies of lifestyle-related diseases have enrolled individuals who participated in these health examinations. The present cross-sectional study is part of the ongoing Yakumo Study.…”

High Salt Intake Is Independently Associated With Hypertensive Target Organ Damage

“…Oxidative stress, an imbalance between ROS production and scavenging, contributes to the development of cardiovascular disease . An association between oxidative stress and microalbuminuria has been reported . Superoxide levels were elevated in arteries of patients with a high‐salt diet .…”

“…Another animal study found that high salt intake increased oxidative stress in the kidney and resulted in increased UACR . An association between ROS and UACR in humans was reported, but there are no studies regarding salt intake, ROS, and UACR in humans.…”

Serum levels of carotenoids in patients with osteonecrosis of the femoral head are lower than in healthy, community-living people

“…This program has been conducted every August since 1982. 30,31 The exclusion criteria of the control group were people with hip diseases and intake of supplements. Finally, 78 healthy, community-living people matched by age, gender, smoking history, habitual alcohol intake, and race (only Japanese) were selected as the control group.…”

“…The serum levels of a-tocopherol (vitamin E) and carotenoids (including zeaxanthin/lutein, b-cryptoxanthin, lycopene, a-carotene, and b-carotene) were measured using high-performance liquid chromatography (HPLC) according to the method we previously reported. 30,31 Briefly, these antioxidant nutrients extracted from 200 ml of serum using n-hexane were dissolved in 100 ml of ethanol, and 20 ml of the solution was then injected into an HPLC system Among approximately 600 carotenoids identified in nature, only six (zeaxanthin, lutein, b-cryptoxanthin, lycopene, a-carotene, and b-carotene) represent more than 95% of total carotenoids in human plasma. 32 The sum of these six carotenoids was then defined as total carotenoids in this study.…”