COMPORTAMENTO do ÓLEO DE GIRASSOL COM ALTO TEOR DE ÁCIDO OLÉICO em TERMOXIDAÇÃO E FRITURA

Óleos de sementes de girassol com diferentes níveis de ácido oléico foram utilizados sob condições de termoxidação e fritura para avaliar o comportamento do óleo de girassol com alto teor de ácido oléico quanto ao seu grau de insaturação quando comparado com o óleo de girassol convencional. Os métodos analíticos aplicados incluíram a determinação de compostos polares totais, quantificação de compostos glicerídicos menores, quantificação da composição triglicerídica, período de indução a 100oC e níveis de a -tocoferol. Os resultados para compostos polares totais apresentaram menores valores em óleo de girassol com alto teor de ácido oléico quando comparados com óleo de girassol convencional. Quanto à distribuição dos compostos glicerídicos menores, verificou-se, de modo geral, que o aumento dos compostos polares totais estava relacionado essencialmente aos compostos de maior peso molecular, isto é, polímeros, dímeros e triglicerídios oxidados, os quais são representantes das alterações térmica e oxidativa. Já os diglicerídios e ácidos graxos, indicativos da alteração hidrolítica, permaneceram praticamente nos níveis originais; uma vez que a umidade não se encontrava presente no meio. A perda quantitativa da composição triglicerídica dependeu do grau de insaturação do triglicerídio, sendo mais elevada em triglicerídios que contêm duas ou três moléculas de ácido linoléico. em todos os casos, o óleo de girassol convencional teve uma maior tendência à polimerização, um maior grau de alteração total e uma maior perda de triglicerídios majoritários que o óleo de girassol com alto teor de ácido oléico. Assim, dentre os óleos utilizados neste estudo, os resultados mostraram um excelente comportamento do óleo de girassol com alto teor de ácido oléico em relação à termoxidação, independente do tipo de aquecimento e à fritura descontínua. Tais resultados demonstraram que sua resistência à alteração termoxidativa estava relacionada com seu baixo teor em ácidos graxos polinsaturados e alto teor em ácido oléico e trioleína.

Hyperlipidemia as a risk factor of renal allograft function impairment

In this study, the graft outcome in renal allograft recipients with [high cholesterol group (HCG), n = 30] or without [normal cholesterol group (NCG), n = 42] hypercholesterolemia and with [high triglyceride group (HTG), n = 33] or without [normal triglyceride group (NTG), n = 36] hypertriglyceridemia were prospectively compared. At 6 months post-transplantation, no significant difference was observed between the groups (NTG compared with HTG, and NCG compared with HCG) regarding age, presence of arterial hypertension, kind of donor (living related or cadaveric), immunosuppressive therapy, number of rejection episodes per patient, frequency of patients with acute cellular rejection, prevalence of patients with diabetes mellitus or proteinuria > 3 g/24 h, and mean serum creatinine. The probability of doubling serum creatinine during follow-up was statistically different between NTG and HTG (12 months: NTG = 0.03, HTG = 0.15; 36 months: NTG = 0.08, HTG = 0.33; 60 months: NTG = 0.08, HTG = 0.48; and 120 months: NTG = 0.18, HTG = 0.48), but not between NCG and HCG (12 months: NCG = 0.05, HCG = 0.13; 36 months: NCG = 0.13, HCG = 0.24; 60 months: NCG = 0.19, HCG = 0.31; 84 months: NCG = 0.27, HCG = 0.31). There was no significant difference in actuarial graft survival between HCG and NCG or between NTG and HTG. Hypertriglyceridemia, but not hypercholesterolemia, was associated with loss of graft function.

Dietary macronutrients, endocrine functioning and intermediary metabolism in broiler chickens - Pair wise substitutions between protein, fat and carbohydrate

Three pens of male broiler chicks were raised under standard conditions and fed from 7 to 42 days of age three isocaloric diets each with 15.8; 19.6 and 19.5% of CP; and 51, 51, and 44% of CHO; and 6.5; 3.0 and 7.7% of fat, and designated as the low protein (LowCP), low lipid (LowL) and low carbohydrate (LowCHO) diets, respectively. Body weights and feed intake were monitored weekly and blood samples were collected at the same time for posterior analysis of hormone and metabolite content. Chickens fed the LowCP diet were characterized by a reduced body weight gain and feed intake and poorer feed conversion efficiency compared to those fed the LowL and LowCHO diets, which were very similar in this respect. Plasma corticosterone and glucose levels and creatine kinase activity were not significantly changed by diet composition. LowCP chickens were characterised by the lowest plasma T-4 and uric acid levels (indicative for reduced protein breakdown and lower protein ingestion) but highest plasma triglyceride levels (congruent with their higher fat deposition) compared to the LowL and LowCHO chickens. LowL chickens had on average higher plasma T-3 and free fatty acid levels compared to the LowCP and LowCHO chickens.In conclusion, a limited substitution of carbohydrate for fat in iso-nitrogenous, iso-energetic diets has no pronounced effects on plasma hormone and metabolite levels, except for the elevation in T-3 (may enhance glucose uptake) and free fatty acid levels in the plasma of the chickens fed the LowL diet. The protein content of the diet has a greater impact on zootechnical performance, and underlying endocrine regulation of the intermediary metabolism compared to the dietary lipid and CHO fraction. (C) 2003 Elsevier B.V. All rights reserved.

Effect of thermal conditioning during embryonic development on aspects of physiological responses of broilers to heat stress

The purpose of the present study was to investigate the effect of thermal conditioning, (through exposure to heat stress), during pre-hatch development on some physiological responses of post-hatch broilers to a post-natal heat stress challenge. Exposure to heat stress at this stage, we hope, may possibly induce epigenetic heat adaptation. Incubating eggs were exposed to temperature of 39.0degreesC for 2 h from Day 13 to 17 of incubation. At 33, 35, 37, 39, 41 and 43 d of age, the broilers hatched from these eggs were housed individually in open-circuit respiration cells. The climatic chambers were set to 22degreesC and increased to 30degreesC for 4 h. O-2 consumption and CO2 production of each chicken was monitored continuously in order to calculate the heat production. Blood samples were obtained before and during the 4 h heat stress. Thermal conditioning during incubation did not affect the plasma T-4, corticosterone, glucose, uric acid and CK concentrations. Temperature challenge, decreased plasma T-3 of broilers of both groups but the decrease was greater in pre-conditioned broilers compared with controls. A similar trend was observed for triglycerides. These changes did not affect total heat production. Since decreased T3 and triglyceride levels are part of the mechanisms for thermoregulation, these suggest that thermal conditioning during incubation can improve the broiler chicken capability for thermotolerance at later post-hatch age. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Acclimation of broiler chickens to chronic high environmental temperature

The present study was conducted to evaluate the zootechnical parameters and age related changes in physiological responses of broiler chickens exposed to hot environment from early age onwards. The broiler chickens were exposed to high temperature (30 degreesC) at 15 d of age and maintained to Day 38 or maintained under thermoneutral environment (control).No significant decrease in feed consumption (FC) and body weight (BW) gain was observed in high temperature group after 7 d of exposure, but in the subsequent period, heat exposure lowered BW and FC, compared to control group. However, the weight gain was not significantly changed after 24 d of exposure, and the feed efficiency was not affected throughout the experimental period.The venous pCO(2) pressure was only significantly decreased by temperature after 24 d of heat exposure. The glucose, non-esterified fatty acid (NEFA), triglyceride (TG), glucose, lipid peroxidation (LPO), creatine kinase (CK), and corticosterone were not influenced by the temperature treatment. The significant decrease in uric acid and increase in lactate concentration due to high temperature were observed respectively at 28 and 35 d of age. The concentrations of triiodothyronine (T-3) and thyroxine (T-4) were changed oppositely at 28 d of age, as T-3 was decreased and T-4 was elevated by high temperature. However, the concentration of T-4 in plasma was decreased whereas T-3 was not changed at 38 d of age. The relationships between the blood parameters were changed due to the temperature treatment, suggesting that not only absolute values but also their interrelationships have to be considered when studying the effects of a particular treatment on physiological functioning.These results suggest the growth and physiological responses of broiler chickens, exposed to high temperature from early age onwards, differed at different stages of acclimation. The process of heat acclimation is related to the mode of heat exposure imposed and is not only reflected in the changes in the absolute concentrations, but also in the correlations among the blood indices.

Dietary macronutrients and performance and plasma hormone and metabolite levels of broiler chickens fat by carbohydrate substitution

The present experiment was aimed to study the effects of an isocaloric substitution of fat by carbohydrate calories while maintaining the same CP content - on some endocrine parameters and key metabolites of the lipid (L), protein (CP) and carbohydrate (CHO) metabolism and muscle cell membrane integrity of broiler chickens. Ninety male broiler chicks (Cobb) were obtained at 1-day old and raised in an environmentally controlled room. Food and water was provided ad libitum. At day 7, the chicks were provided with the experimental diets: Control diet (CON: 20% CP; 9.1% L; 39.6% CHO), Low lipid diet (LowL: 22% CP; 3.36% L; 59.7% CHO), and low carbohydrate diet (LowCHO: 22% CP; 8.09% L; 46.7% CHO). T e chickens fed the CON manifested the best growth rate feed conversion compared to both other groups. The CO chickens showed the highest plasma T-3 Concentrations at 14 days of age as compared to both LowL and LowCHO chickens. At 35 days of age however, LowL chickens were characterized by the highest plasma T-3 levels. Overall, CON birds had the highest plasma T-4 levels (P < 0.0001) compared to LowL and LowCHO chickens. Plasma corticosterone levels were not affected by diet composition. Glucose levels increased towards the end of the experimental period, but there was no overall effect of diet composition on plasma glucose levels. Chickens fed the CON diet were consistently characterized by the highest plasma uric acid levels compared to LowL and LowCHO chickens. Irrespectively of diet, plasma triglyceride levels were high at 14 days of age, then decreased and finally increased again during the last week. This latter increase was most pronounced for the CON chickens and is congruous with their high fat deposition. At 28 days of age, a significant effect of diet was observed, as CON birds had lower plasma free fatty acid (FFA) levels compared to LowL but not to LowCHO chickens. However there was no overall effect of diet composition on plasma FFA levels. Creatine kinase (CK) activities increased significantly with age and were consistently higher in CON chickens. In conclusion, fast growth in broiler chickens is positively correlated with catabolism of protein from dietary or endogenous origin and (muscle) cell membrane disruption as reflected in high plasma uric acid levels and CK activity, respectively. The currently investigated substitution of fat by CHO had no marked effects on endocrine functioning and intermediary metabolism, but this does not exclude that larger substitutions between both nutrients can have an effect.

Relationship between diet and anticoagulant response to warfarin - A factor analysis

Background Diet composition is one of the factors that may contribute to intraindividual variability in the anticoagulant response to warfarin. Aim of the study To determine the associations between food pattern and anticoagulant response to warfarin in a group of Brazilian patients with vascular disease. Methods Recent and usual food intakes were assessed in 115 patients receiving warfarin; and corresponding plasma phylloquinone (vitamin K-1), serum triglyceride concentrations, prothrombin time (PT), and International Normalized Ratio (INR) were determined. A factor analysis was used to examine the association of specific foods and biochemical variables with anticoagulant data. Results Mean age was 59 +/- 15 years. Inadequate anticoagulation, defined as values of INR 2 or 3, was found in 48% of the patients. Soybean oil and kidney beans were the primary food sources of phylloquinone intake. Factor analysis yielded four separate factors, explaining 56.4% of the total variance in the data set. The factor analysis revealed that intakes of kidney beans and soybean oil, 24-h recall of phylloquinone intake, PT and INR loaded significantly on factor 1. Triglycerides, PT, INR, plasma phylloquinone, and duration of anticoagulation therapy loaded on factor 3. Conclusion Fluctuations in phylloquinone intake, particularly from kidney beans, and plasma phylloquinone concentrations were associated with variation in measures of anticoagulation (PT and INR) in a Brazilian group of patients with vascular disease.

Evaluation of the thermal diffusivity of vegetable oils during frying by Thermal Lens Spectrometry

In this work we report on the use of the Thermal Lens method to verify the evolution of the thermal diffusivity of sunflower and soybean vegetable oils utilized in preparation of twenty five snacks portions. Our results show that the thermal diffusivity for sunflower oil does not change between 1 and 25 portions of fried snacks. By another hand, the soybean thermal diffusivity exhibits a little decrease for higher portion of fried snacks, indicating that for this oil the triglyceride level is reduced as a degradation process.

Fiber fermentability effects on energy and macronutrient digestibility, fecal traits, postprandial metabolite responses, and colon histology of overweight cats

Considering the different potential benefits of divergent fiber ingredients, the effect of 3 fiber sources on energy and macronutrient digestibility, fermentation product formation, postprandial metabolite responses, and colon histology of overweight cats (Felis catus) fed kibble diets was compared. Twenty-four healthy adult cats were assigned in a complete randomized block design to 2 groups of 12 animals, and 3 animals from each group were fed 1 of 4 of the following kibble diets: control (CO; 11.5% dietary fiber), beet pulp (BP; 26% dietary fiber), wheat bran (WB; 24% dietary fiber), and sugarcane fiber (SF; 28% dietary fiber). Digestibility was measured by the total collection of feces. After 16 d of diet adaptation and an overnight period without food, blood glucose, cholesterol, and triglyceride postprandial responses were evaluated for 16 h after continued exposure to food. on d 20, colon biopsies of the cats were collected under general anesthesia. Fiber addition reduced food energy and nutrient digestibility. of all the fiber sources, SF had the least dietary fiber digestibility (P < 0.05), causing the largest reduction of dietary energy digestibility (P < 0.05). The greater fermentability of BP resulted in reduced fecal DM and pH, greater fecal production [g/(cat x d); as-is], and greater fecal concentration of acetate, propionate, and lactate (P < 0.05). For most fecal variables, WB was intermediate between BP and SF, and SF was similar to the control diet except for an increased fecal DM and firmer feces production for the SF diet (P < 0.05). Postprandial evaluations indicated reduced mean glucose concentration and area under the glucose curve in cats fed the SF diet (P < 0.05). Colon mucosa thickness, crypt area, lamina propria area, goblet cell area, crypt mean size, and crypt in bifurcation did not vary among the diets. According to the fiber solubility and fermentation rates, fiber sources can induce different physiological responses in cats, reduce energy digestibility, and favor glucose metabolism (SF), or improve gut health (BP).

Chronic consumption of fructose rich soft drinks alters tissue lipids of rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of Passiflora edulis on the Metabolic Profile of Diabetic Wistar Rat Offspring

Dry extract of the genus Passiflora has been shown to help control glycemia and lipid levels. The objective of this study was to evaluate the effects of passion fruit (P. edulis) on the biochemical profile of offspring from diabetic rats. Diabetes was induced by streptozotocin. The diabetes group consisted of 10 rats with glucose levels greater than 200 mg/dL; the nondiabetic (control) group consisted of 10 rats with glucose levels less than 120 mg/dL. After the diagnosis of diabetes, the mating phase was started. By day 21 of pregnancy, the offspring were born; the dams were kept in individual cages with their offspring until the weaning period. The offspring were then divided into 4 groups (n = 15 each): G1 were offspring from control dams, G2 were offspring from treated nondiabetic dams, G3 were offspring from diabetic dams, and G4 were offspring from treated diabetic dams. For 30 consecutive days, G1 and G3 offspring were treated with vehicle (oral gavage) and G2 and G4 offspring were treated with passion fruit juice (oral gavage). After 30-day treatment, the animals were anesthetized and killed, and blood was drawn immediately for analysis of the biochemical profile (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and glucose). The G2 and G4 rats showed significantly reduced total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels and an increased high-density lipoprotein cholesterol level. The use of passion fruit juice improved lipid profiles, suggesting that this plant may have beneficial effects in the prevention and treatment of dyslipidemias and hyperglycemia.

Rapid, quantitative determination of polar compounds in fats and oils by solid-phase extraction and size-exclusion chromatography using monostearin as internal standard

A rapid and simple method was developed for quantitation of polar compounds in fats and oils using monostearin as internal standard. Starting from 50 mg of oil sample, polar compounds were obtained by solid-phase extraction (silica cartridges) and subsequently separated by high-performance size-exclusion chromatography into triglyceride polymers, triglyceride dimers, oxidized triglyceride monomers, diglycerides, internal standard and fatty acids. Quantitation of total polar compounds was achieved through the internal standard method and then amounts of each group of compounds could be calculated. A pool of polar compounds was used to check linearity, precision and accuracy of the method, as well as the solid-phase extraction recovery. The procedure was applied to samples with different content of polar compounds and good quantitative results were obtained, especially for samples of low alteration level.

Efeito de um novo produto fermentado de soja sobre os lípides séricos de homens adultos normocolesterolêmicos

This study was undertaken to verify the effect of a daily intake of a new fermented soy milk produced with Enterococcus faecium and Lactobacillus jugurti on the serum lipid levels in normocholesterolemic middle-aged men. The study was randomized, double-blind and placebo-controlled and was performed for a period of 6 weeks. Forty-four normocholesterolemic healthy, male volunteers, aged 40-55 years old were randomly separated in two groups: The F-group received 200 ml of the fermented product daily and the P-group received 200 ml of placebo (chemically fermented). The blood samples were drawn initially and after 3 and 6 weeks and serum values for total cholesterol, HDL-cholesterol and triglyceride were determined. The LDL-cholesterol value was estimated. No significant changes in the fermented group (F) were observed for total cholesterol, LDL-cholesterol or triglyceride levels, while the HDL-cholesterol level was significantly higher (p≤ 0,05) after 6 weeks. The total cholesterol and LDL-cholesterol levels were significantly higer (p≤ 0,05) in the placebo group (P), but no changes were found for the HDL-cholestrol and triglyceride levels during the experimental period. In conclusion, the intake of 200 ml/day of the fermented soy milk, produced with E.faecium and L. jugurti, for 6 weeks, did not affect the serum total cholesterol and LDL-cholesterol, and led an increase of 10% in the HDL-cholesterol level.

Independent impact of glycemia ad blood pressure in albuminuria on high-risk subjects for metabolic syndrome

Background: Microalbuminuria may reflect diffuse endothelial damage. Considering that diabetes and hypertension cause vasculopathy, we investigated associations of albumin-to-creatinine ratio (ACR) with plasma glucose and blood pressure levels in high-risk subjects for metabolic syndrome. Methods: A sample of 519 (246 men) Japanese-Brazilians (aged 60 ± 11 years), who participated in a population-based study, had their ACR determined in a morning urine specimen. Backward models of multiple linear regression were created for each gender including log-transformed values of ACR as dependent variable; an interaction term between diabetes and hypertension was included. Results: Macroalbuminuria was found in 18 subjects. ACR mean values for subjects with normal glucose tolerance, impaired fasting glycemia, impaired glucose tolerance and diabetes were 9.9 ± 6.0, 19.0 ± 35.4, 20.7 ± 35.4, and 33.9 ± 55.0 mg/g, respectively. Diabetic subjects showed higher ACR than the others (p < 0.05). An increase in the proportion of albuminuric subjects was observed as glucose metabolism deteriorated (4.9, 17.0, 23.0 and 36.0%). Stratifying into 4 groups according to postchallenge glycemia (< 7.8 mmol/l, n = 9 1; ≥ 7.8 mmol/l, n = 4 10) and hypertension, hypertensive and glucose-intolerant subgroups showed higher ACR values. ACR was associated with gender, waist circumference, blood pressure, plasma glucose and triglyceride (p < 0.05); albuminuric subjects had significantly higher levels of such variables than the normoalbuminuric ones. In the final models of linear regression, systolic blood pressure and 2-hour glycemia were shown to be independent predictors of ACR for both genders (p < 0.05). In men, also waist was independently associated with ACR. No interaction was detected between diabetes and hypertension. Conclusions: These findings suggest that both glucose intolerance and hypertension could have independent but not synergistic effects on endothelial function - reflected by albumin loss in urine. Such hypothesis needs to be confirmed in prospective studies. © 2004 Dustri-Verlag Dr. K. Feistle.

The β-chemokines MIP-1α and RANTES and lipoprotein metabolism in HIV-infected Brazilian patients

HIV patients are predisposed to the development of hypertriglyceridemia and hypercholesterolemia as a result of both viral infection and HIV infection therapy, especially the protease inhibitors. Chemokines and cytokines are present at sites of inflammation and can influence the nature of the inflammatory response in atherosclerosis. We investigated the correlation between biochemical variables and β-chemokines (MIP-1α and RANTES) and the apolipoprotein E genotype in HIV-infected individuals. The apolipoproteins were measured by nephelometry. Triglycerides and total cholesterol were determined by standard enzymatic procedures. The β-chemokines were detected by ELISA. The genetic category of CCR5 and apolipoprotein E were determined by PCR amplification and restriction enzymes. Immunological and virological profiles were assessed by TCD4 + and TCD8 + lymphocyte counts and viral load quantification. Positive correlations were found between apo E and CD8 + (p = 0.035), apo E and viral load (p = 0.018), MIP-1α and triglycerides (p = 0.039) and MIP-1α and VLDL (p = 0.040). Negative correlations were found between viral load and CD4 + (p = 0.05) and RANTES and CD4 + (p = 0.029). The β-chemokine levels may influence lipid metabolism in HIV-infected individuals. © 2005 by The Brazilian Journal of Infectious Diseases and Contexto Publishing. All rights reserved.