Publications by authors named "Meydani M"

Background: Epidemiologic studies suggest that fruit and vegetable (F&V) consumption is inversely associated with incidence of cardiovascular disease (CVD). However, evidence for causality is lacking, and the underlying mechanisms are not well understood.

Objectives: We aimed to determine whether there is a causal relation between consuming high levels of F&V and prevention of atherosclerosis, the hallmark of CVD pathogenesis.

View Article and Find Full Text PDF

Background: Epidemiological studies suggest that higher fruits and vegetables (F&V) consumption correlates with reduced risk of hepatic steatosis, yet evidence for causality and the underlying mechanisms is lacking.

Objectives: We aimed to determine the causal relation between F&V consumption and improved metabolic disorders in mice fed high-fat (HF) (Experiment-1) or normal-fat (Experiment-2) diets and its underlying mechanisms.

Methods: Six-week-old male C57BL/6J mice were randomly grouped and fed diets supplemented at 0%-15% (wt:wt) with a freeze-dried powder composed of 24 commonly consumed F&V (human equivalent of 0-9 servings/d) for 20 wk.

View Article and Find Full Text PDF

Background: Commonly consumed mushrooms, portobello (PBM) and shiitake (SHM), are abundant in nutrients, soluble dietary fibers, and bioactive compounds that have been implicated as beneficial in reducing inflammation, improving lipid profiles, and ameliorating heart disease and atherosclerosis, an inflammatory disease of the arteries.

Objective: The aim of this study was to determine effects of PBM and SHM in preventing atherosclerosis and associated inflammation in an animal model.

Methods: Four-week-old Ldlr-/- male mice were divided into 5 dietary groups for 16 wk: a low-fat control (LF-C, 11 kcal% fat), high-fat control (HF-C, 18.

View Article and Find Full Text PDF
Article Synopsis
  • Curcuminoids from turmeric have different biological activities, attributed to their varying cellular uptake mechanisms that are not well understood.
  • This study aimed to investigate how factors such as polarity, transporters, metabolism, and medium components influence the cellular uptake of the three main curcuminoids: curcumin (CUR), bisdemethoxycurcumin (BDMC), and demethoxycurcumin (DMC).
  • Results showed that the differences in cellular uptake were primarily due to the medium components, particularly bovine serum albumin (BSA), which influenced how each curcuminoid interacted and was absorbed by cells.
View Article and Find Full Text PDF

Background: Dietary bioactive compounds capable of improving metabolic profiles would be of great value, especially for overweight individuals undergoing a caloric restriction (CR) regimen. Curcumin (Cur), a possible anti-obesity compound, and piperine (Pip), a plausible enhancer of Cur's bioavailability and efficacy, may be candidate agents for controlling body fat, metabolism and low grade inflammation.

Methods: 47 eight-week-old male C57BL/6 mice were fed a high fat diet (HFD) for 23 weeks to induce obesity.

View Article and Find Full Text PDF

Oats, in addition to cholesterol-lowering properties, contain unique antioxidants called avenanthramides (Avns), which inhibit both inflammatory cytokines and adhesion molecules in endothelial cells in culture. This study evaluated the effects of Avns of oats on atherosclerosis in Ldlr mice, one of the most commonly used atherosclerosis mouse models with their similar cholesterol distributions to humans. The Ldlr mice were fed a low fat, high fat, high fat containing regular oat brans with low levels of Avns (HFLA), or high fat containing regular oat brans with high levels of Avns (HFHA) diet.

View Article and Find Full Text PDF
Article Synopsis
  • - Emerging research indicates that menaquinones, forms of vitamin K from bacteria, may have unique health benefits, particularly anti-inflammatory properties, but their true significance in relation to vitamin K needs and inflammation is unclear.
  • - A study involving 80 participants (men and postmenopausal women) assessed fecal menaquinone levels and their links to serum vitamin K, gut bacteria composition, and inflammation markers while following a 6-week diet of either whole grains or refined grains.
  • - Results showed significant variability in fecal menaquinone excretion, with lower levels found on the whole grain diet; however, these menaquinones were absent in serum, and no connection was found between fecal menaquinones and inflammation markers. *
View Article and Find Full Text PDF

High-fat diets (HFDs) and excess adiposity increase proinflammatory cytokines in the colon, altering gene expression in a manner that promotes the development of colorectal cancer (CRC). Thus, compounds that reduce this biochemical inflammation are potential chemopreventive agents. Curcumin (CUR), a dietary polyphenol, and salsalate (SAL), a non-steroidal anti-inflammatory drug, are both anti-inflammatories.

View Article and Find Full Text PDF

Observational studies suggest an inverse association between whole-grain (WG) consumption and inflammation. However, evidence from interventional studies is limited, and few studies have included measurements of cell-mediated immunity. We assessed the effects of diets rich in WGs compared with refined grains (RGs) on immune and inflammatory responses, gut microbiota, and microbial products in healthy adults while maintaining subject body weights.

View Article and Find Full Text PDF

The effect of whole grains on the regulation of energy balance remains controversial. We aimed to determine the effects of substituting whole grains for refined grains, independent of body weight changes, on energy-metabolism metrics and glycemic control. The study was a randomized, controlled, parallel-arm controlled-feeding trial that was conducted in 81 men and postmenopausal women [49 men and 32 women; age range: 40-65 y; body mass index (in kg/m): <35.

View Article and Find Full Text PDF
Article Synopsis
  • The CD36 scavenger receptor is involved in binding and internalizing various ligands, including α-tocopherol (αT) and α-tocopheryl phosphate (αTP), which influences cellular signaling and gene expression.
  • Research shows that αTP and EPC-K1 trigger stronger internalization of CD36 than αT, and this process is inhibited by sulfo-N-succinimidyl oleate (SSO), affecting the uptake of these compounds differently.
  • αTP promotes VEGF expression in monocytes through the CD36/PI3Kγ/Akt signaling pathway, highlighting its role in modulating angiogenesis related to other molecules such as amyloid beta and oxLDL.
View Article and Find Full Text PDF
Article Synopsis
  • * The study observed that curcumin supplementation (500, 1000, 1500 mg/kg for 4 months) restored cAMP levels in the liver and adipose tissues of mice, which were suppressed by the HFD, thus influencing lipid metabolism.
  • * Curcumin activates the cAMP/PKA/CREB pathway, leading to increased lipolysis and fatty acid oxidation, suggesting its beneficial effects on lipid homeostasis and anti-atherosclerotic properties.
View Article and Find Full Text PDF
Article Synopsis
  • The review explores vitamin E's potential as an antioxidant in preventing diseases linked to oxidative stress, such as cardiovascular issues and cancer, but finds clinical studies limit its effectiveness.
  • New research suggests that vitamin E may have non-antioxidant roles, influencing cell signaling and gene expression, particularly through phosphorylation processes that modify its function.
  • Despite these findings, higher levels of vitamin E in the body can still provide antioxidant benefits, especially when the vitamin's chromanol ring remains unprotected.
View Article and Find Full Text PDF

Natural peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists are found in food and may be important for health through their anti-inflammatory properties. Curcumin (Cur) is a bright yellow spice, derived from the rhizome of Curcuma longa Linn. It has been shown to have many biological properties that appear to operate through diverse mechanisms.

View Article and Find Full Text PDF

Background: Both aging and obesity are related to dysregulated immune function, which may be responsible for increased risk of infection and also chronic non-infectious diseases. Dietary lipids have been shown to impact immune and inflammatory responses and cardio-metabolic risk factors. No information on the impact of olive oil on immune responses of overweight and obese older adults is available.

View Article and Find Full Text PDF

In several studies, vitamin E has been observed to influence angiogenesis and vasculogenesis. We recently showed that the phosphorylated form of α-tocopherol (αT), α-tocopheryl phosphate (αTP), increases the expression of the vascular endothelial growth factor (VEGF). Thus, αTP may act as an active lipid mediator increasing VEGF expression, angiogenesis, and vasculogenesis.

View Article and Find Full Text PDF

The vitamin E derivative, alpha-tocopheryl phosphate (αTP), is detectable in cultured cells, plasma and tissues in small amounts, suggesting the existence of enzyme(s) with α-tocopherol (αT) kinase activity. Here, we characterize the production of αTP from αT and [γ-32P]-ATP in primary human coronary artery smooth muscle cells (HCA-SMC) using separation by thin layer chromatography (TLC) and subsequent analysis by Ultra Performance Liquid Chromatography (UPLC). In addition to αT, although to a lower amount, also γT is phosphorylated.

View Article and Find Full Text PDF

Cardiovascular disease remains the leading cause of morbidity and mortality in the United States and other developed countries, and is fast growing in developing countries, particularly as life expectancy in all parts of the world increases. Current recommendations for the prevention of cardiovascular disease issued jointly from the American Academy of Cardiology and American Heart Association emphasize that lifestyle modification should be incorporated into any treatment plan, including those on statin drugs. However, there is a dearth of data on the interaction between diet and statins with respect to additive, complementary or antagonistic effects.

View Article and Find Full Text PDF

We have previously shown that curcumin (CUR) may increase lipid accumulation in cultured human acute monocytic leukaemia cell line THP-1 monocytes/macrophages, but that tetrahydrocurcumin (THC), an in vivo metabolite of CUR, has no such effect. In the present study, we hypothesised that the different cellular uptake and/or metabolism of CUR and THC might be a possible explanation for the previously observed differences in their effects on lipid accumulation in THP-1 monocytes/macrophages. Chromatography with tandem MS revealed that CUR was readily taken up by THP-1 monocytes/macrophages and slowly metabolised to hexahydrocurcumin sulphate.

View Article and Find Full Text PDF

Objectives: Epidemiological and experimental evidence have indicated potential health benefits of vitamin E supplementation on coronary heart disease (CHD), but several clinical trials have reported no benefit from vitamin E supplementation on CHD. We hypothesized that supplemental intake of vitamin E from an early age may prevent or retard the development and progression of atherosclerosis and CHD mortality.

Methods: To test this hypothesis, 300 Ldlr(-/-) mice were divided into groups receiving Western style high fat/cholesterol (HFHC), moderate fat/cholesterol (MFMC), or low fat/cholesterol (LFLC) diets all containing 50 IU of vitamin E.

View Article and Find Full Text PDF

Objective: Consuming curcumin may benefit health by modulating lipid metabolism and suppressing atherogenesis. Fatty acid binding proteins (FABP-4/aP2) and CD36 expression are key factors in lipid accumulation in macrophages and foam cell formation in atherogenesis. Our earlier observations suggest that curcumin's suppression of atherogenesis might be mediated through changes in aP2 and CD36 expression in macrophages.

View Article and Find Full Text PDF

Background: Provision of fortified juices may provide a convenient method to maintain and increase blood fat-soluble vitamins.

Objective: To determine whether children consuming orange juice fortified with calcium and combinations of vitamins D, E, and A could increase serum 25-hydroxyvitamin D [25(OH)D], α-tocopherol, and retinol levels.

Design: A 12-week randomized, double-blind, controlled trial.

View Article and Find Full Text PDF

Of the 8 different analogues (α-, β-, γ-, δ-tocopherols and tocotrienols) designated as vitamin E, alpha-tocopherol (α-T) has been mostly studied, together with gamma-tocopherol (γ-T) which is abundant in the US diet. We compared the effect of dietary supplementation with adequate or high doses of α-T or γ-T on the number and type of genes expressed following T cell activation. C57BL/6 mice were fed diets containing adequate (30 ppm) or high (500 ppm) amounts of α-T or γ-T for 4 weeks.

View Article and Find Full Text PDF

Background: Obesity is associated with low-grade inflammation and impaired immune response. Caloric restriction (CR) has been shown to inhibit inflammatory response and enhance cell-mediated immune function. Curcumin, the bioactive phenolic component of turmeric spice, is proposed to have anti-obesity and anti-inflammation properties while piperine, another bioactive phenolic compound present in pepper spice, can enhance the bioavailability and efficacy of curcumin.

View Article and Find Full Text PDF

Recent evidence suggests potential benefits from phytochemicals and micronutrients in reducing the elevated oxidative and lipid-mediated stress associated with inflammation, obesity, and atherosclerosis. These compounds may either directly scavenge reactive oxygen or nitrogen species or they may modulate the activity of signal transduction enzymes leading to changes in the expression of antioxidant genes. Alternatively, they may reduce plasma lipid levels by modulating lipid metabolic genes in tissues and thus reduce indirectly lipid-mediated oxidative and endoplasmic reticulum stress through their hypolipidemic effect.

View Article and Find Full Text PDF