Calcium pyruvate in the attenuation of the water deficit on the agro-industrial quality of ratoon sugarcane.

Sugarcane is one of the largest agricultural commodities when considering the export volume and the number of jobs generated. Sugarcane production in the Brazilian Northeast region is generally low due to several factors, including the irregular rainfall distribution, which highlights the importance of studies aimed at mitigating the deleterious effects of water stress. In this scenario, this study aimed to evaluate calcium pyruvate as a water deficit attenuator on the agro-industrial quality of sugarcane in the second cycle of cultivation. The experiment was conducted out under greenhouse conditions of the Federal University of Campina Grande, where five sugarcane commercial genotypes tested (G1- RB863129, G2- RB92579, G3- RB962962, G4- RB021754, and G5- RB041443) and three irrigation management strategies (E1- full irrigation, E2- water deficit with application of 30 mM of calcium pyruvate, and E3- water deficit without calcium pyruvate application), distributed in randomized blocks in 5 × 3 factorial arrangement with three replications. The RB021754 genotype under water deficit and without foliar application of calcium pyruvate increased the fiber content (13.2%) and the sugarcane moist cake weight (143.5 g). The effects of water deficit in sugarcane genotypes are attenuated by the exogenous application of 30 mM of calcium pyruvate, with benefits on the polarized sucrose content, apparent sucrose content of the juice, soluble solids content, purity, corrected cane POL, total recoverable sugars, and stem mass in relation to plants under water deficit without calcium pyruvate application.

Salicylic acid concentrations and forms of application mitigate water stress in sour passion fruit seedlings.

The present study aimed to evaluate concentrations and forms of application of salicylic acid used for water stress mitigation on the gas exchange and growth of yellow passion fruit. The experimental design was arranged in randomized blocks in a 4 × 4 × 2 factorial scheme, with four concentrations of salicylic acid (SA) via foliar application (0.0, 0.7, 1.4, and 2.1 mM), four SA concentrations via fertigation (0.0, 0.7, 1.4, and 2.1 mM), and two irrigation depths estimated based on the actual evapotranspiration - ETr (50 and 100% of ETr), with three replications. Water stress negatively affected the physiology and growth of yellow passion fruit seedlings at 75 days after sowing (DAS). The application of salicylic acid, regardless of the form of application, attenuates the effects of water stress on gas exchange and growth of yellow passion fruit, with the best results obtained when applying a concentration of 1.30 mM via leaf or 0.90 mM via fertirrigation. The combination of foliar application of AS and fertigation contributed to improve photosynthetic and growth parameters under water conditions of 50 and 100% of ETr. The foliar application of AS presents superior responses to the application via fertigation. These results reinforce the hypothesis that the attenuation of water stress by salicylic acid is related to the maintenance of gas exchange, which depends on the concentration and form of application, and studies testing combinations throughout the crop cycle become promising for advances in knowledge from the action of this phytohormone on abiotic stress.

Mineral composition and production of guava under salt stress and salicylic acid.

The limitation in the quality of water sources for irrigation in the semi-arid region of northeastern Brazil is increasingly present, so it is necessary to use water with high concentrations of salts for agricultural production, which makes the use of elicitors essential to mitigate the harmful effects of salinity on plants. Given the above, the objective of this study was to evaluate the effects of foliar application of salicylic acid on the mineral composition and production of guava plants under salt stress conditions in the post-grafting phase. The experiment was carried out under greenhouse conditions, in a randomized block design, in a 2 × 4 factorial scheme, with two levels of electrical conductivity of irrigation water (0.6 and 3.2 dS m-1) and four concentrations of salicylic acid (0, 1.2, 2.4, and 3.6 mM), with three replicates. During the flowering stage of guava, N, P, and K contents accumulated in the leaves according to the following order of concentration: N > K > P. Foliar application of 1.2 mM of salicylic acid increases the leaf contents of N, P, and K in guava plants grown under irrigation with water of 0.6 dS m-1. Water salinity of 3.2 dS m-1 reduces the growth and production components of guava plants.

Methods of application of salicylic acid as attenuator of salt stress in cherry tomato.

Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.

Micellar effects and analytical applications of nitro substitution in 4-Nitro-N-alkyl-1,8-naphthalimide by cysteine derivatives.

The aromatic nucleophilic substitution reactions of the nitro group of 4-Nitro-N-alkyl-1,8-naphthalimides by thiolate anions produce fluorescent derivatives and their rates are strongly accelerated by micelles of hexadecyltrimethylammonium chloride even at low pH. Acceleration factors of this reactions can reach million-fold. As the products are oxidant-insensible, this reaction allows the determination of SH- containing compounds such as cysteine, glutathione or proteins even in oxidative conditions. Limits of detection are as low as 5 × 10-7 M, ten times lower than the limit for the classic 5,5'-dithiobis-(2-nitrobenzoic) acid method. Moreover, this reaction can be developed at pHs between 6.5 and 7.5 thereby diminishing the rate of spontaneous oxidation of the thiols. In addition, we demonstrated that 4-Nitro-N-alkyl-1,8-naphthalimides can be used to evidence SH groups in peptides, proteins and living cells.

Vitamin D restriction enhances periovarian adipose tissue inflammation in a model of menopause.

Background: Menopause and deficiency in vitamin D (VD) are two health problems usually associated with aging women.Objective: We aimed to study inflammation in visceral adipose tissue when bilateral ovariectomy is combined with dietary restriction in VD.Methods: We studied 60 female C57BL/6 mice 3 months of age. Half of the animals had bilateral ovariectomy (Ovx group, n = 30) and half a sham procedure (Control [C] group, n = 30), and half of each Ovx or C group were fed a standard diet containing VD or a diet restricted in VD (D-) for an additional 12 weeks. Therefore, four groups were formed (n = 15 each group): C, C(D-), Ovx, and Ovx(D-). After sacrifice, the periovarian adipose tissue (PAT) was investigated.Results: In PAT, we observed different levels of hypertrophied adipocytes, enhanced proinflammatory cytokines, activation of inflammatory markers, and components of the extracellular signal-regulated kinase. The most affected PAT was seen in the Ovx(D-) group, followed by the Ovx group, the C(D-) group, and the C group (the least altered).Conclusion: The results demonstrate that ovariectomy and dietary restriction of VD are inducers of adverse effects on mouse visceral adipose tissue. When combined, these insults might enhance PAT inflammation.

Beneficial effects of maternal swimming during pregnancy on offspring metabolism when the father is obese.

We aimed to evaluate the impact of maternal exercise training on the offspring metabolism and body size caused by father obesity. C57BL/6 male 4-week-old mice were fed a high-fat diet (HF father) or control diet (C father), while equal age female mice were fed only a C diet and were separated into two groups: trained (T mother) and non-trained (NT mother), and at 12 weeks of age mice were mated. A continuous swimming protocol was applied for 10 weeks (before and during gestation), and offspring were followed since weaning until sacrifice (at 12 weeks of age). HF father, compared to C father, showed obesity, elevated total cholesterol (TC) and triglycerides (TG), and glucose intolerance. Both sexes HF/NT offspring showed hyperglycemia, glucose intolerance and high levels of TC and TG, without obesity. However, HF/T offspring showed data close to C/NT, demonstrating the beneficial effect of maternal exercise in the offspring of obese fathers.

Liver metabolism in adult male mice offspring: consequences of a maternal, paternal or both maternal and paternal high-fructose diet.

The study aimed to evaluate the consequences of the consumption of a high-fructose diet (HFR; fructose was responsible for 45% of the energy from carbohydrates) by the mother, the father, or both on C57BL/6 adult male offspring. Non-consanguineous parents received the diet (HFR or control, C) from 8 weeks before mating until weaning (n=10 fathers and n=10 mothers on each diet). After weaning, only the C diet was offered to offspring. The groups were formed by one male randomly taken from each litter. The offspring groups were identified according to the mother's diet (the first letter), then the father's diet (the second letter), that is, C/C, C/HFR, HFR/C, HFR/HFR (n=10 per group). The parents exhibited the following characteristics: compared with those of the C group, the HFR parents had higher blood pressure (BP), enlarged liver, increased hepatic triacylglycerol content, hypercholesterolemia, hypertriglyceridemia, high plasma leptin and low adiponectin. The offspring exhibited the following characteristics: compared with the C/C group, the HFR/HFR group had high BP. The C/HFR, HFR/C and HFR/HFR showed elevated uric acid and leptin levels and diminished adiponectin. The HFR/HFR group showed liver inflammation (increased NFκB, SOCS3, JNK, TNF-α, IL1-ß and IL6 levels). Likewise, SREBP-1c and FAS were upregulated. In conclusion, the consumption of a HFR by the mother and/or father is associated with adverse effects on liver metabolism in adult male offspring. When both mother and father are fed a HFR, the adverse effects on the offspring are more severe.

Label-Free Proteomics of a Defined, Binary Co-culture Reveals Diversity of Competitive Responses Between Members of a Model Soil Microbial System.

Interactions among members of microbial consortia drive the complex dynamics in soil, gut, and biotechnology microbiomes. Proteomic analysis of defined co-cultures of well-characterized species provides valuable information about microbial interactions. We used a label-free approach to quantify the responses to co-culture of two model bacterial species relevant to soil and rhizosphere ecology, Bacillus atrophaeus and Pseudomonas putida. Experiments determined the ratio of species in co-culture that would result in the greatest number of high-confidence protein identifications for both species. The 281 and 256 proteins with significant shifts in abundance for B. atrophaeus and P. putida, respectively, indicated responses to co-culture in overall metabolism, cell motility, and response to antagonistic compounds. Proteins associated with a virulent phenotype during surface-associated growth were significantly more abundant for P. putida in co-culture. Co-culture on agar plates triggered a filamentous phenotype in P. putida and avoidance of P. putida by B. atrophaeus colonies, corroborating antagonistic interactions between these species. Additional experiments showing increased relative abundance of P. putida under conditions of iron or zinc limitation and increased relative abundance of B. atrophaeus under magnesium limitation were consistent with patterns of changes in abundance of metal-binding proteins during co-culture. These results provide details on the nature of interactions between two species with antagonistic capabilities. Significant challenges remaining for the development of proteomics as a tool in microbial ecology include accurate quantification of low-abundance peptides, especially from rare species present at low relative abundance in a consortium.

Assessment of Spleen Filtrate Function in Renal Transplant Recipients Using Technetium-99m Stannous Colloid Liver-Spleen Scan.

BACKGROUND: Functional hyposplenism (FH) is indicated by an anatomically present spleen that fails to take up radiolabeled colloid. The occurrence of FH has been reported in a small group of renal transplant recipients based on hematologic parameters. The aim of this study was to replicate this association in a larger group of renal transplant recipients with the use of technetium-99m-stannous colloid liver-spleen scan to assess the spleen function. METHODS: This survey based on single samples enrolled 101 unselected adult patients with functional kidney grafts >180 days after transplantation. All patients underwent 99mTc-stannous colloid scan to assess spleen function as well as bone marrow uptake of radiocolloid along with an anatomic and blood flow study of the spleen and kidney with the use of Doppler sonography. RESULTS: The prevalence of hyposplenism was 32.7% (33/101) for the cohort, and increased uptake of radiocolloid by the bone marrow was seen in 9.9% (10/101). According to the multivariate analysis, the frequency of hyposplenism was significantly influenced by indirect bilirubin and hemoglobin, and direct bilirubin and neutrophil count remained as independent predictors of bone marrow uptake. CONCLUSIONS: This study demonstrated that a group of renal transplant recipients has FH. In addition, bone marrow uptake might be interpreted as liver dysfunction. In this situation, the small amount of contrast (spleen compared with liver) would leave hyposplenism undiagnosed. Further prospective and longitudinal clinical studies are needed to determine the clinical impact of this condition on the management of renal transplant recipients.

Mutational profile of TP53 in esophageal squamous cell carcinoma associated with chagasic megaesophagus.

Chaga's disease is an important communicable neglected disease that is gaining wider attention due to its increasing incidence worldwide. Achalasia due to chagasic megaesophagus (CM), a complication of this disease, is a known-yet, poorly understood-etiological factor for esophageal squamous cell carcinoma (ESCC) development. In this study, we aimed to perform the analysis of TP53 mutations in a series of Brazilian patients with ESCC that developed in the context CM (ESCC/CM), and to compare with the TP53 mutation profile of patients with benign CM and patients with nonchagasic ESCC. Additionally, we intended to correlate the TP53 mutation results with patient's clinical pathological features. By polymerase chain reaction (PCR) followed by direct sequencing of the hotspot regions of TP53 (exon 5 to 8), we found that TP53 mutations were present in 40.6% (13/32) of the ESCC/CM group, 45% (18/40) of the nonchagasic ESCC group, and in only 3% (1/33) of the benign CM group. Missense mutations were the most common in the three groups, yet, the type and mutated exon mutation varied significantly among the groups. Clinically, the groups exhibited distinct features, with both cancer groups (ESCC and ESCC/CM) been significantly associated higher consumption of alcohol and tobacco, older age, worse Karnofsky performance status, poor outcome than the patients with benign CM. No significant association was found between TP53 mutation profile and clinical-pathological features in any of the three groups. We describe first the time the analysis of TP53 mutations in ESCC that developed in the context of CM, and the observed high frequency of mutations, suggest that TP53 also plays an important role in the tumorigenic process of this unexplored etiological condition.

High-intensity interval training (swimming) significantly improves the adverse metabolism and comorbidities in diet-induced obese mice.

AIM: Controlling obesity and other comorbidities in the population is a challenge in modern society. High-intensity interval training (HIIT) combines short periods of high-intensity exercise with long recovery periods or a low-intensity exercise. The aim was to assess the impact of HIIT in the context of diet-induced obesity in the animal model. METHODS: C57BL/6 mice were fed one of the two diets: standard chow (Lean group - LE) or a high--fat diet (Obese group - OB). After twelve weeks, the animals were divided into non-trained groups (LE--NT and OB-NT) and trained groups (LE-T and OB--T), and began an exercise protocol. For biochemical analysis of inflammatory and lipid profile, we used a colorimetric enzymatic method and an automatic spectrophotometer. One-way ANOVA was used for statistical analysis of the experimental groups with Holm-Sidak pos hoc test. Two-way ANOVA analyzed the interactions between diet and HIIT protocol. RESULTS: HIIT leads to significant reductions in body mass, blood glucose, glucose tolerance and hepatic lipid profile in T-groups compared to NT-groups. HIIT was able to reduce plasma levels of inflammatory cytokines. Additionally, HIIT improves the insulin immunodensity in the islets, reduces the adiposity and the hepatic steatosis in the T-groups. HIIT improves beta--oxidation and peroxisome proliferator--activated receptor (PPAR)-alpha and reduces lipogenesis and PPAR--gamma levels in the liver. In skeletal muscle, HIIT improves PPAR--alpha and glucose transporter-4 and reduces PPAR--gamma levels. CONCLUSION: HIIT leads to attenuate the adverse effects caused by a chronic ingestion of a high-fat diet.

Temporal patterns in the intertidal faunal community at the mouth of a tropical estuary.

The use of intertidal sandy beaches by fish and macrocrustaceans was studied at different temporal scales at the mouth of a tropical estuary. Samples were taken along the lunar and diel cycles in the late dry and rainy seasons. Fish assemblage (number of species, density and biomass), crustaceans and wrack biomass, showed significant interactions among all studied factors, and the combination of moon phase and diel cycle, resulting in different patterns of environmental variables (depth, water temperature and dissolved oxygen), affected habitat use by the different species. Variances in faunal community were detected between seasons, stimulated by salinity fluctuations from freshwater input during the rainy season. These differences suggest an important cycling of habitats and an increase in connectivity between adjacent habitats (estuary and coastal waters). Moreover, the results showed that this intertidal sandy beach also provides an alternative nursery and protected shallow-water area for the initial development phase of many marine and estuarine species. In addition, this intertidal habitat plays an important role in the maintenance of the ecological functioning of the estuarine-coastal ecosystem continuum.

Crescimento e tolerância à salinidade em três espécies medicinais do gênero Plectranthus expostas a diferentes níveis de radiação / Growth and salinity tolerance in three medicinal species of the genus Plectranthus exposed to different levels of solar radiation

No cultivo de plantas medicinais as condições de salinidade e de luz podem exercer influência no rendimento e na qualidade final da produção de biomassa. O objetivo deste trabalho foi avaliar o efeito de diferentes luminosidades e níveis de salinidade na água de irrigação sobre o crescimento e tolerância de três espécies de plantas do gênero Plectranthus. O ensaio foi conduzido em parcelas subsubdivididas com cinco repetições, sendo as parcelas referente ao fator ambiente (pleno sol e telado), as subparcelas aos níveis de salinidade na água de irrigação - CEa (0,7; 1,9; 3,1; 4,3 e 5,5 dS m-1), e as subsubparcelas às três espécies do gênero Plectranthus (P. amboinicus, P. barbatus e P. grandis). As variáveis de resposta foram: índice relativo de clorofila (IRC), área foliar (AF), razão de área foliar (RAF), área foliar específica (AFE), matéria seca da parte aérea (MSPA), matéria seca das raízes (MSR), matéria seca total (MST), relação MSR/MSPA, grau de tolerância à salinidade, e teor dos íons Na+ e K+. O estresse salino reduziu o crescimento das plantas, sendo as maiores reduções observadas nas plantas expostas a pleno sol. A salinidade influenciou a partição de matéria seca, sendo as raízes mais afetadas do que a parte aérea. Com o aumento da CEa houve aumento expressivo no teor foliar de Na+, enquanto o teor de K+ e o IRC foram reduzidos. Entretanto, o acúmulo de Na+ foi menor em P. grandis. Considerando-se a MST, verificou-se que as três espécies se mostraram moderadamente tolerantes à salinidade de até 3,1 dS m-1, exceto P. grandis cultivada em telado, classificada como tolerante. Em relação ao grau de redução na produção MSPA (parte de interesse comercial), poderia se recomendar o cultivo de P. grandis quando a água de irrigação contiver CEa de até 3,1 dS m-1.

In the cultivation of medicinal plants, salinity and light can affect the yield and quality of biomass. The objective of this study was to evaluate the effect of light and salinity levels of the irrigation water on the growth and salt tolerance of three medicinal plant species of the genus Plectranthus. A completely randomized split-plot design with five repetitions was used. The plots were formed by the environment of cultivation (full sunlight and greenhouse), the subplots by the salinity in the irrigation water - ECw (0.7, 1.9, 3.1, 4.3 and 5.5 dS m-1), and the subsubplots by the three plant species (P. amboinicus, P. barbatus and P. grandis). The following variables were evaluated: relative chlorophyll index (RCI), leaf area (LA), leaf area ratio (LAR), specific leaf area (SLA), shoot dry mass (SDM), root dry mass (RDM), total dry mass (TDM), RDM/SDM ratio, relative salt tolerance, and concentration of Na+ and K+ in leaves. Salinity reduced plant growth, with the greatest reductions observed in plants exposed to full sunlight. Salinity affected the dry matter partitioning, and the roots were more affected than the shoot. With increasing ECw, there was a significant increase in the concentration of Na+ in the leaves, while K+ and RCI decreased. However, the increase in Na+ accumulation was lower in P grandis. The three species were moderately tolerant to salinity up to 3.1 dS m-1, considering the total dry mass production, except the P. grandis grown in greenhouse, classified as tolerant. Regarding the relative reduction in shoot dry mass (part of commercial interest), we could recommend the cultivation of P. grandis when the available irrigation water presents values of ECw up to 3.1 dS m-1.

Orthotopic liver transplantation without venovenous bypass: 125 cases from a single center.

AIM: This study analyzed a 10-year single-center experience in orthotopic liver transplantation (OLT) without venovenous bypass (VVB). METHODS: We retrospectively analysed a nonrandomized series (1999-2008) of 125 adult OLT patients without VVB. RESULTS: The main causes of liver failure were viral hepatitis (n = 39), alcoholic liver disease (n = 22), and liver cancer (n = 17). One-year survival was 76.4%. The most common postoperative complications were bile duct stenosis (n = 12), postoperative bleeding (n = 8), hepatic artery thrombosis (n = 7), and primary liver failure (n = 6). Twelve patients required hemodialysis and four underwent retransplantations of the liver. Fourteen patients died before postoperative day 30(th). Univariate analysis showed significant differences between patients who did and did not survive 30 days among donor death diagnoses (P = .05), red blood cell units transfused (P = .03), aspartate aminotranferase on the first postoperative day (P = .002), ABO type (P = .04), time of orotracheal intubation (P = .001), hemodialysis (P = .001), and period of postoperative vasoactive drug use (P = .006). The total length of orotracheal tube intubation showed a significant independent association with mortality before 30 days (P < .001). CONCLUSION: OLT without VVB can be safely performed even in severe cases of chronic liver failure.

Developmental origins of health and disease: experimental and human evidence of fetal programming for metabolic syndrome.

The concept of developmental origins of health and disease has been defined as the process through which the environment encountered before birth, or in infancy, shapes the long-term control of tissue physiology and homeostasis. The evidence for programming derives from a large number of experimental and epidemiological observations. Several nutritional interventions during diverse phases of pregnancy and lactation in rodents are associated with fetal and neonatal programming for metabolic syndrome. In this paper, recent experimental models and human epidemiological studies providing evidence for the fetal programming associated with the development of metabolic syndrome and related diseases are revisited.

Orthotopic liver transplantation without venovenous bypass using the conventional and piggyback techniques.

INTRODUCTION: Orthotopic liver transplantation is a widely used procedure for the treatment of irreversible liver diseases for which there is no possibility of medical treatment. When this procedure is performed by the conventional technique, the retrohepatic vena cava is removed along with the native liver. The inferior vena cava (IVC) remains clamped until the revascularization of the graft, and in this period there is a reduction in the venous return, which may induce a fall by up to 50% in the cardiac output with hemodynamic instability and a fall in renal perfusion pressure. The use of a portal-femoral-axillary venovenous bypass system, in which the blood from the femoral and portal veins returns to the heart via the axillary vein propelled by a centrifugal pump, is intended to minimize the effects of the IVC clamping. In the piggyback (PB) technique, the native liver is removed and the IVC of the recipient is preserved and only partially clamped. We have employed both techniques without the use of venovenous bypass for 10 years. The objective of this study was to compare the results obtained from the use of the two techniques. PATIENTS AND METHODS: A retrospective analysis was performed of 195 patients transplanted between 1999 and 2008: 125 by the conventional technique and 70, the PB technique. The intraoperative parameters were analyzed (surgical time, ischemia time, use of blood products, and diuresis), as well as intensive care support (duration of stay in intensive care unit and use of vasoactive drugs), period of intubation, length of hospital stay, renal function, graft function, postoperative complications, retransplantation, and patient survival. RESULTS: The PB group showed a reduction in surgical time, warm ischemia time, the use of packed red blood cells concentrates, and fresh frozen plasma, as well as mortality at 30 days (P<.05). There were no differences in relation to cold ischemia time, intraoperative diuresis; length of stay and use of vasoactive drugs in the intensive care unit; the period of intubation; the duration of hospital stay; the renal function; the graft function; the need for reoperation; the incidence of sepsis, biliary complications, vascular complications; need for retransplantation; and 1-year mortality. The cumulative survival rate at 1 year was significantly better among the PB patients. CONCLUSION: Orthotopic liver transplantation can be performed without venovenous bypass with good results, using either the conventional technique or the PB technique. Provided that there is no technical contraindication and a long ischemia period is not foreseen, the PB technique should be the technique of choice.

High fat diets modulate nitric oxide biosynthesis and antioxidant defence in red blood cells from C57BL/6 mice.

The consumption of a high fat (HF) diet is considered a risk factor for the development of obesity. On the other hand, a monounsaturated HF diet has beneficial cardiometabolic effects. Since nitric oxide (NO) modulates vascular homeostasis, we investigate whether HF diets that vary in fatty acid composition have a different effect on theL-arginine-NO pathway and oxidative stress in C57BL/6 mice red blood cells (RBC). The olive oil diet induced an activation of L-arginine transport compared to other diets. NO synthase (NOS) activity was increased in all unsaturated HF diets (olive, sunflower and canola oils). Moreover, the expression of endothelial NOS (eNOS) and inducible NOS (iNOS) was increased in the olive oil group. In contrast, NOS activity from the lard group was decreased associated with diminished l-arginine transport. Olive oil also induced superoxide dismutase activation. Inhibition of the L-arginine-NO pathway in the lard group could contribute to cardiovascular diseases, while unsaturated HF diets may have a protector effect via enhanced NO bioavailability.