kc Hayes

kc Hayes
Brandeis University · Department of Biology

DVM, PhD

About

264
Publications
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Publications

Publications (264)
Article
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Objective: Whether dietary carbohydrate (CHO) or fat is more involved in type 2 diabetes (T2DM) induction uncomplicated by dietary fiber was addressed in a spontaneous diabetic model, the diurnal Nile rat that mimics the human condition. Methods: A total of 138 male Nile rats were fed plant-based and animal-based saturated fat where 10% energy a...
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Tyrosine hydroxylase (TH) catalyzes the hydroxylation of L-tyrosine to L-DOPA. This is the rate-limiting step in the biosynthesis of the catecholamines – dopamine (DA), norepinephrine (NE), and epinephrine (EP). Catecholamines (CA) play a key role as neurotransmitters and hormones. Aberrant levels of CA are associated with multiple medical conditio...
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Objective: The Nile rat (Arvicanthis niloticus) is a superior model for Type-II Diabetes Mellitus (T2DM) induced by diets with a high glycemic index (GI) and glycemic load (GLoad). To better define the age and gender attributes of diabetes in early stages of progression, weanling rats were fed a high carbohydrate (hiCHO) diet for between 2 to 10 we...
Article
Controversy remains about how diet affects the vascular endothelial dysfunction associated with disordered insulin-glucose homeostasis. It is postulated that the type and level of certain macronutrients contribute to endothelial dysfunction in vascular diabetes complications. However, it is not well understood how specific macronutrients affect the...
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Palm fruit juice (PFJ) containing oil palm phenolics is obtained as a by-product from oil palm (Elaeis guineensis) fruit milling. It contains shikimic acid, soluble fibre and various phenolic acids including p-hydroxybenzoic acid and three caffeoylshikimic acid isomers. PFJ has also demonstrated beneficial health properties in various biological mo...
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Type II diabetes mellitus (T2DM) is a multifactorial disease involving complex genetic and environmental interactions. No single animal model has so far mirrored all the characteristics or complications of diabetes in humans. Since this disease represents a chronic nutritional insult based on a diet bearing a high glycemic load, the ideal model sho...
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Background: Dietary modification helps prevent and manage Metabolic Syndrome (MetS) and Type 2 Diabetes Mellitus (T2DM) in humans and Nile rats. Specifically fibrous legumes, like lentils, benefit humans, but whether this reflects a specific change in the Glycemic Load (GLoad) remains controversial. Accordingly, low-GLoad foods were tested in the...
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Background The Nile rat (NR, Arvicanthis niloticus) is a model of carbohydrate-induced type 2 diabetes mellitus (T2DM) and the metabolic syndrome. A previous study found that palm fruit juice (PFJ) delayed or prevented diabetes and in some cases even reversed its early stages in young NRs. However, the molecular mechanisms by which PFJ exerts these...
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A variety ofmodified fats that provide different functionalities are used in processed foods to optimize product characteristics and nutrient composition. Partial hydrogenation results in the formation of trans FAs (TFAs) and was one of the most widely used modification processes of fats and oils. However, the negative effects of commercially produ...
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The role of lymphatics in atherosclerosis is not yet understood. Here, we investigate lymphatic growth dynamics and marker expression in atherosclerosis in apolipoprotein E-deficient (apoE(-/-)) mice. The prolymphangiogenic growth factor, VEGF-C, was elevated in atherosclerotic aortic walls. Despite increased VEGF-C, we found that adventitial lymph...
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Addition of clinically-relevant levels of 3′-Azido-3′-deoxythymidine (AZT) to cultured HepG2 cells increases the number of reactive radical species (reactive oxygen and nitrogen species [ROS and RNS]) as well as random mutations in mitochondrial DNA (mtDNA). Co-treatment of AZT-exposed cells with palm fruit juice (PFJ) mitigates AZT mutagenesis. Th...
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With the increasing incidence of metabolic diseases, numerous bioactive phytochemicals have been proffered in the dietary prevention of these conditions. Palm fruit juice (PFJ) possesses bioactive phenolic compounds (referred to as oil palm phenolics; OPP) that may deter diabetes. The objective of the present experiments was to document the degree...
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The pathogenesis of diabetic retinopathy (DR) in metabolic syndrome (MetS) and type 2 diabetes (T2D) is not well studied, partly because an appropriate model has not been developed. Recently, we introduced a novel model of spontaneous T2D and MetS that replicates the relevant features of the human disease. In the current study, we investigated the...
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Amount and type of dietary carbohydrate (CHO), as well as the CHO:fat ratio, are thought to be critical for both the rate of development and severity of Type 2 diabetes mellitus. Thus, these nutritional considerations were examined in the previously described "spontaneous" model of diabetes and metabolic syndrome, the Nile rat. Weanling male Nile r...
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Objective: Foods incorporating plant sterols (PS) consistently decrease serum low-density lipoprotein cholesterol (LDL-C), although results vary depending on the PS form and food matrix. The objective was to study the effect of a novel triglyceride-recrystallized phystosterol (TRP) incorporated into fat-free milk on markers of cardiovascular risk...
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It is well established that plant phenolics elicit various biological activities, with positive effects on health. Palm oil production results in large volumes of aqueous by-products containing phenolics. In the present study, we describe the effects of oil palm phenolics (OPP) on several degenerative conditions using various animal models. OPP red...
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Waste from agricultural products represents a disposal liability, which needs to be addressed. Palm oil is the most widely traded edible oil globally, and its production generates 85 million tons of aqueous by-products annually. This aqueous stream is rich in phenolic antioxidants, which were investigated for their composition and potential in vitr...
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To replace dietary trans fatty acids (TFA), two practical options exist: revert to a natural saturated fat without cholesterol (most likely palm oil or its fractions) or move to a newer model of modified fat hardened by interesterification (IE). This review summarizes the relative risks for cardiovascular disease inherent in these options. Interest...
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The prevalence of Metabolic Syndrome and related chronic diseases, among them non-insulin-dependent (type 2) diabetes mellitus, are on the rise in the United States and throughout the world. Animal models that respond to environmental stressors, such as diet, are useful for investigating the outcome and development of these related diseases. Within...
Data
Table S1. Food and water intake, body weight and blood glucose of 8-wk old maleNile rats with different onset to diabetes fed Western-type diet for 24 wks (Expt 3)
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To determine whether lutein supplementation will slow visual function decline in patients with retinitis pigmentosa receiving vitamin A. Randomized, controlled, double-masked trial of 225 nonsmoking patients, aged 18 to 60 years, evaluated over a 4-year interval. Patients received 12 mg of lutein or a control tablet daily. All were given 15,000 IU/...
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Metabolic syndrome (MetS) is a prevalent and complex disease, characterized by the variable coexistence of obesity, dyslipidemia, hyperinsulinaemia, and hypertension. The alarming rise in the prevalence of metabolic disorders makes it imperative to innovate preventive or therapeutic measures for MetS and its complications. However, the elucidation...
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We have used a new ApoA-I transgenic mouse model to identify by global gene expression profiling, candidate genes that affect lipid and lipoprotein metabolism in response to fenofibrate treatment. Multilevel bioinformatical analysis and stringent selection criteria (2-fold change, 0% false discovery rate) identified 267 significantly changed genes...
Article
Lipoprotein metabolism was assessed in hamsters following subcutaneous injection of AgNO3. Apolipoprotein serum amyloid A (apoSAA) peaked at 36 h, followed by elevations in plasma cholesterol at 56 h and triglycerides at 96 h. There was a striking increase in LDL and a de-crease in HDL. Migration of all acute phase (AP) lipoproteins was retarded co...
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We have used a new apoA-1 transgenic mouse model in order to identify by global gene expression profiling, candidate genes that affect plasma lipids and HDL following fenofibrate treatment. Multi-level bioinformatical analysis and stringent selection criteria (2-fold change, 0% false discovery rate) identified 267 significantly changed genes involv...
Article
Polydextrose is a randomly bonded polysaccharide produced by the bulk melt polycondensation of glucose and sorbitol in vacuo. It has been used as a bulking and texturizing agent and soluble fiber ingredient in many food products worldwide for over two decades. Because of its atypical linkages between glucose moieties, polydextrose resists digestion...
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The cholesterol-raising potential of saturated fats has been noted for 50 years, but how they function and which among the saturated fats are most to blame is only now becoming apparent. The focus has shifted from saturated fats to individual fatty acids and the total composite of fatty acids (SFA, MUFA, PUFA) that comprise our daily fat intake. An...
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Although more sophisticated ways exist to analyze TG-MS than that applied in our study, the approach was able to identify the TG species sufficiently to emphasize the importance of TG structure. The criticism that differences in dietary fat saturation alone would explain the lipoprotein response across diets is not supported by careful scrutiny of...
Article
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Dietary trans-rich and interesterified fats were compared to an unmodified saturated fat for their relative impact on blood lipids and plasma glucose. Each fat had melting characteristics, plasticity and solids fat content suitable for use as hardstock in margarine and other solid fat formulations. Thirty human volunteers were fed complete, whole f...
Article
Because polydextrose (PDX) functions as a carbohydrate with reduced absorption, its potential to lower plasma lipids was assessed in gerbils and in humans. In one experiment, gerbils were fed purified diets containing 0.15% cholesterol and either 0% or 6% PDX for 4 weeks. In the second, gerbils received a cholesterol-free diet with 0% or 6% PDX for...
Article
To determine whether phytosterols (PST) facilitate excretion of whole body cholesterol and whether dietary fat or enhancing gallbladder contraction with curcumin might influence this process, four experiments were conducted in gerbils. In Experiment 1, naive gerbils received cholesterol-free purified diets with 30% energy from fat and 0% or 0.75% f...
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To determine whether a therapeutic dose of docosahexaenoic acid (DHA), an omega-3 fatty acid, will slow the course of retinal degeneration in adult patients with retinitis pigmentosa who are also receiving vitamin A. Randomized, controlled, double-masked trial of 221 patients, aged 18 to 55 years, evaluated over a 4-year interval. Patients were giv...
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To determine whether docosahexaenoic acid will slow the course of retinal degeneration in subgroups of patients with retinitis pigmentosa who are receiving vitamin A. A cohort of 208 patients with retinitis pigmentosa, aged 18 to 55 years, were randomly assigned to 1200 mg of docosahexaenoic acid plus 15 000 IU/d of vitamin A given as retinyl palmi...
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When free phytosterols are adequately heated and then cooled in fat, they recrystallize and are rendered bioavailable for blocking cholesterol absorption. To extend the application of phytosterols to fried foods, the activity of these modified crystals was assessed in 2 experiments with 26 male gerbils fed purified diets containing 0.15 g/100 g cho...
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Epidemiological and clinical studies have established that the n-6 fatty acid, linoleic acid (LA), and the n-3 fatty acids, linolenic acid (LNA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) collectively protect against coronary heart disease (CHD). LA is the major dietary fatty acid regulating low-density lipoprotein (LDL)-C metabol...
Article
To evaluate the sub-acute and sub-chronic effect of large doses of betaine, this trimethyl glycine compound was fed to rats. Initial studies at BIBRA in the UK evaluated intakes of 0, 1, 2, and 5% betaine added to a maintenance chow designed for use in toxicology studies. Male and female Sprague-Dawley rats were followed for up to 90 days. No toxic...
Article
To compare the relative impact of trans-18:1 with the two main dietary saturated fatty acids it replaces, plasma lipid response was assessed in Mongolian gerbils fed diets rich in 16:0 (24%en),18:0 (10%en), or trans-18:1 (4 or 6%en). The diets were designed such that the 18:0-rich diet substituted 7%en as 18:0 for 16:0, whereas 4%en and 6%en from t...
Article
Hamsters were fed five diets (eight/group) for 4 weeks. Control diet was casein-based, containing American Fat Blend, coconut oil, 0.05 wt.% cholesterol. In diet 2, amaranth flakes partly replaced casein, starch, and corn oil. In diet 3, crude amaranth oil replaced all corn oil and some coconut oil. Diet 4 contained refined amaranth oil. Diet 5 con...
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Conjugated linoleic acid (CLA) reportedly exerts anticarcinogenic and antiatherosclerotic effects in animals. To test the hypothesis that the putative antiatherosclerotic effect of CLA might derive from an anti-inflammatory or antioxidant action on lipoprotein metabolism, an acute phase response (APR) was elicited in hamsters while varying dietary...
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To better understand the relative absorption of 18:0, specific structured triglycerides (STG) with varied ratios of 18:0 and short-chain organic acids (2:0, 3:0, 4:0) were compared with naturally occurring 18:0 in cocoa butter and to other mono- and diglycerides (DGs) containing 18:0. A bioassay for available fat energy was developed for growing Sp...
Article
The potential of free phytosterols (including 20% stanols) to lower plasma and liver lipids was assessed in three experiments with gerbils fed diets containing cholesterol. The first explored the ability of phytosterols (0.5%) to block absorption of 0.05, 0.10, and 0.5% cholesterol. The second assessed the importance of consuming phytosterols (0.75...
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How much fat [as % total calories]and which types oof fat their fatty acids are reviewed in term of their impact on lipoprotein metabolism and cardiovascular risk. The P:S ratio of 1:1 is important, but the issue is complicated because the energy status of the host at intervention with diet [genetic permissiveness] affects the response, eg. the nat...
Article
Milk fat may contribute to atherogenesis in humans. We sought to offset the atherogenic potential of milk fat by adding polyunsaturated fat and vitamin E to milk. We measured plasma lipids, lipoproteins, and tocopherol and LDL oxidation in normolipemic adults. In experiment 1 (n = 48), we compared delivery of 100 mg all-rac-alpha-tocopheryl acetate...
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It has been suggested that the molecular species or structure of the triglyceride, i.e. not only what fatty acids are present but also their relative order in the sn1, 2, or 3 position on the triglyceride, can influence the metabolism of the triglyceride and its fatty acids, including lipoprotein metabolism. One rationale for this possibility assum...
Article
The Syrian golden hamster is a frequently used model to study cholesterol and bile acid metabolism as well as cholesterol-induced cholelithiasis. However, diet-induced gallstones seem limited to young male hamsters of certain strains that develop depressed cholate/chenodeoxycholate bile acid ratios. To further elucidate gender and age specific aspe...
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Vitamin A supplementation is being used successfully to treat some forms of cancer and the degenerative eye disease retinitis pigmentosa. The daily biological need for vitamin A is estimated to be 800 retinol equivalents (RE)/d (2667 IU/d) for adult women and 1000 RE/d (3300 IU/d) for adult men; doses > or = 7500 RE (> or = 25000 IU)/d are consider...
Article
In plasma, the bulk of apoSAA, a positive acute phase reactant protein, is transported in high density lipoproteins (HDL), especially HDLH (apoA1-rich HDL). In this study we tested whether apoA1 deficiency would adversely affect apoSAA concentration and lipid distribution in mouse plasma lipoproteins. Acute phase response (APR) was induced in C57BL...
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A therapeutic effect of vitamin A supplementation on the course of photoreceptor degeneration, previously reported for patients with retinitis pigmentosa, was tested in two transgenic mouse models of this disease, each carrying a dominant rhodopsin mutation. The threonine-17 --> methionine (T17M) mutation is a class II rhodopsin mutation, character...
Article
Although dietary fatty acid saturation is an effective modulator of plasma cholesterol, its effects on bile acid metabolism are not well elucidated. In fact, it is possible that primary changes in bile acid metabolism account for the response in plasma lipids. Thus, the aim of this study was to compare the effect of a diet rich in specific saturate...
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The imbalance that develops between low-density lipoprotein (LDL) production and clearance during saturated fat consumption is responsible for expanding the circulating LDL pool. To assess the imbalance attributable to fatty acids alone, i.e., without the interaction of dietary cholesterol, the most fat-sensitive species available (the gerbil) was...
Article
In an attempt to improve the nutritional value of animal fats (including milkfat and lard), two technological approaches (i.e., cholesterol removal by steam distillation and linoleic acid enrichment by addition of safflower oil) were tested for cholesterolemic effects in a cohort of 29 older women (age 68 +/- 7 years). Test fat sources were incorpo...