Eliziária C. Santos

Red but not white meat consumption is associated with metabolic syndrome, insulin resistance and lipid peroxidation in Brazilian middle-aged men

Background The influence of diet on metabolic syndrome and oxidative stress are not completely known. Design This cross-sectional study assessed the association of red meat and white meat consumption with metabolic syndrome, insulin resistance and lipid peroxidation in Brazilian middle-aged men. Methods A total of 296 subjects (age: 50.5 ± 5.0 years, body mass index: 25.8 ± 3.5 kg/m2) were evaluated. Anthropometry, lifestyle features, blood biochemical parameters, diagnosis of metabolic syndrome, homeostatic model assessment for insulin resistance, a lipid peroxidation marker (oxidized low-density lipoprotein) and triglycerides:high-density lipoprotein cholesterol ratio were assessed. Dietary intake was estimated by a food frequency questionnaire. Results The subjects included in the highest tertile red meat (≥81.5 g/d) and saturated fatty acid from red meat consumption (≥4.3 g/d) had higher occurrence of central obesity (nearly 60%, p < 0.01), hypertriglyceridaemia (nearly 43%, p < 0.01) and metabolic syndrome (35%, p < 0.01). They also had higher values of homeostatic model assessment for insulin resistance, oxidized low-density lipoprotein, and triglycerides:high-density lipoprotein cholesterol ratio, regardless of interfering factors. There were no associations of highest white meat tertile (≥39.4 g/d) and saturated fatty acid from white meat (≥1.0 g/d) consumption with the assessed parameters (p > 0.05). Conclusions Red meat consumption was cross-sectionally associated with the occurrence of central obesity, hypertriglyceridaemia, and metabolic syndrome as well as with higher homeostatic model assessment for insulin resistance, oxidized low-density lipoprotein concentrations and triglycerides:high-density lipoprotein cholesterol ratio. The content of saturated fatty acid from red meat consumption may be a factor that contributed to this relationship, while white meat consumption was not associated with metabolic syndrome and the assessed biomarkers.

Concomitant Benznidazole and Suramin Chemotherapy in Mice Infected with a Virulent Strain of Trypanosoma cruzi

ABSTRACT Although suramin (Sur) is suggested as a potential drug candidate in the management of Chagas disease, this issue has not been objectively tested. In this study, we examined the applicability of concomitant treatment with benznidazole (Bz) and suramin in mice infected with a virulent strain of Trypanosoma cruzi. Eighty 12-week-old male C57BL/6 mice were equally randomized in eight groups: (i) noninfected mice (negative control) and mice infected with T. cruzi Y strain receiving (ii) no treatment (positive control), (iii) Bz, 100 mg/kg of body weight per day, (iv) Sur, 20 mg/kg/day, and (v to viii) Sur, 20 mg/kg/day, combined with Bz, 100, 50, 25, or 5 mg/kg/day. Bz was administered by gavage, and Sur was administered intraperitoneally. Sur dramatically increased the parasitemia, cardiac content of parasite DNA, inflammation, oxidative tissue damage, and mortality. In response to high parasitic load in cardiac tissue, Sur stimulated the immune system in a manner typical of the acute phase of Chagas disease, increasing tissue levels of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and inducing a preferential IgG2a anti-T. cruzi serum pattern. When Sur and Bz were combined, the infection severity was attenuated, showing a dose-dependent Bz response. Sur therapy had a more harmful effect on the host than on the parasite and reduced the efficacy of Bz against T. cruzi infection. Considering that Sur drastically reinforced the infection evolution, potentiating the inflammatory process and the severity of cardiac lesions, the in vivo findings contradicted the in vitro anti-T. cruzi potential described for this drug.

The energy density of laser light differentially modulates the skin morphological reorganization in a murine model of healing by secondary intention

This study investigates the influence of gallium–arsenide (GaAs) laser photobiostimulation applied with different energy densities on skin wound healing by secondary intention in rats. Three circular wounds, 10 mm in diameter, were made on the dorsolateral region of 21 Wistar rats weighting 282.12 ± 36.08 g. The animals were equally randomized into three groups: Group SAL, saline solution 0.9%; Group L3, laser GaAs 3 J/cm2; Group L30, laser GaAs 30 J/cm2. Analyses of cells, blood vessels, collagen and elastic fibres, glycosaminoglycans and wound contraction were performed on the scar tissue from different wounds every 7 days for 21 days. On day 7, 14 and 21, L3 and L30 showed higher collagen and glycosaminoglycan levels compared to SAL (P < 0.05). At day 21, elastic fibres were predominant in L3 and L30 compared to SAL (P < 0.05). Type‐III collagen fibres were predominant at day 7 in both groups. There was gradual reduction in these fibres and accumulation of type‐I collagen over time, especially in L3 and L30 compared with SAL. Elevated density of blood vessels was seen in L30 on days 7 and 14 compared to the other groups (P < 0.05). On these same days, there was higher tissue cellularity in L3 compared with SAL (P < 0.05). The progression of wound closure during all time points investigated was higher in the L30 group (P < 0.05). Both energy densities investigated increased the tissue cellularity, vascular density, collagen and elastic fibres, and glycosaminoglycan synthesis, with the greater benefits for wound closure being found at the density of 30 J/cm2.

Curcumin enhances the anti-Trypanosoma cruzi activity of benznidazole-based chemotherapy in acute experimental Chagas disease

ABSTRACT Although curcumin can increase the effectiveness of drugs against malaria, combination therapies using the molecule have never been investigated in Chagas disease (ChD). Therefore, we evaluated the efficacy of curcumin as a complementary strategy to benznidazole (Bz)-based chemotherapy in mice acutely infected with Trypanosoma cruzi. Eighty-four 12-week-old Swiss mice were equally randomized into seven groups: uninfected (NI), T. cruzi infected and untreated (INF), infected and treated with 100 mg/kg of body weight Bz (B100), 50 mg/kg Bz (B50), 100 mg/kg curcumin (C100), 100 mg/kg Bz plus 100 mg/kg curcumin (B100 plus C100), and 50 mg/kg Bz plus 100 mg/kg curcumin (B50 plus C100). After microscopic identification of blood trypomastigotes (4 days after inoculation), both drugs were administered by gavage once a day for 20 days. Curcumin showed limited antiparasitic, anti-inflammatory, and antioxidant effects when administered alone. When curcumin and Bz were combined, there was a drastic reduction in parasitemia, parasite load, mortality, anti-T. cruzi IgG reactivity, circulating levels of cytokines (gamma interferon [IFN-γ], interleukin 4 [IL-4], and MIP1-α), myocardial inflammation, and morphological and oxidative cardiac injury; these results exceeded the isolated effects of Bz. The combination of Bz and curcumin was also effective at mitigating liver toxicity triggered by Bz, increasing the parasitological cure rate, and preventing infection recrudescence in noncured animals, even when the animals were treated with 50% of the recommended therapeutic dose of Bz. By limiting the toxic effects of Bz and enhancing its antiparasitic efficiency, the combination of the drug with curcumin may be a relevant therapeutic strategy that is possibly better tolerated in ChD treatment than Bz-based monotherapy.

Acute paraquat exposure determines dose-dependent oxidative injury of multiple organs and metabolic dysfunction in rats: impact on exercise tolerance.

This study investigated the pathological morphofunctional adaptations related to the imbalance of exercise tolerance triggered by paraquat (PQ) exposure in rats. The rats were randomized into four groups with eight animals each: (a) SAL (control): 0.5 ml of 0.9% NaCl solution; (b) PQ10: PQ 10 mg/kg; (c) PQ20: PQ 20 mg/kg; and (d) PQ30: PQ 30 mg/kg. Each group received a single injection of PQ. After 72 hours, the animals were subjected to an incremental aerobic running test until fatigue in order to determine exercise tolerance, blood glucose and lactate levels. After the next 24 h, lung, liver and skeletal muscle were collected for biometric, biochemical and morphological analyses. The animals exposed to PQ exhibited a significant anticipation of anaerobic metabolism during the incremental aerobic running test, a reduction in exercise tolerance and blood glucose levels as well as increased blood lactate levels during exercise compared to control animals. PQ exposure increased serum transaminase levels and reduced the glycogen contents in liver tissue and skeletal muscles. In the lung, the liver and the skeletal muscle, PQ exposure also increased the contents of malondialdehyde, protein carbonyl, 8‐hydroxy‐2′‐deoxyguanosine, superoxide dismutase and catalase, as well as a structural remodelling compared to the control group. All these changes were dose‐dependent. Reduced exercise tolerance after PQ exposure was potentially influenced by pathological remodelling of multiple organs, in which glycogen depletion in the liver and skeletal muscle and the imbalance of glucose metabolism coexist with the induction of lipid, protein and DNA oxidation, a destructive process not counteracted by the upregulation of endogenous antioxidant enzymes.

Nonsteroidal anti-inflammatory is more effective than anti-oxidant therapy in counteracting oxidative/nitrosative stress and heart disease in T. cruzi-infected mice

We compared the relevance of ibuprofen, vitamins C and E to control oxidative/nitrosative stress and heart disease in mice infected by Trypanosoma cruzi. Swiss mice were randomized into five groups: control, uninfected; infected without treatment; and infected treated with vitamins C, E or ibuprofen. Animals were inoculated with 2000 trypomastigote forms of T. cruzi. After 20 days, infected mice presented reduced vitamin C and E tissue levels, high cytokines (interferon gamma, tumour necrosis factor-α, interleukin 10 and chemokine ligand 2), prostaglandin F2α (PGF2α ) and nitric oxide (NO) cardiac production, intense myocarditis and reactive tissue damage, which was directly correlated with the intensity of the inflammatory infiltrate and the degree of pathological cardiac remodelling. Vitamins C and E supplementation were irrelevant to counteract reactive tissue damage and myocarditis in infected animals. Conversely, ibuprofen reduced tissue levels of cytokines, PGF2α and NO, as well as lipid and protein oxidation, antioxidant enzyme activity and the cardiac damage, without interfering with heart parasitism. Our results do not support the applicability of vitamin C and E supplementation in the management of acute Chagas cardiomyopathy. By controlling the inflammatory infiltrate, anti-inflammatory-based therapy proved to be a more rational strategy than a direct antioxidant therapy in attenuating oxidative/nitrosative stress and cardiac damage.

Modulation of oxidative and inflammatory cardiac response by nonselective 1- and 2-cyclooxygenase inhibitor and benznidazole in mice.

This study investigated the combined effects of benznidazole (BZ) and ibuprofen (IB) on the oxidative and inflammatory status of the cardiac tissue in vivo.

Cadmium-induced testicular damage is associated with mineral imbalance, increased antioxidant enzymes activity and protein oxidation in rats

Aims: Currently, the spectrum of pathological manifestations associated with cadmium‐induced testicular toxicity is poorly understood. Thus, we investigated the impact of cadmium (Cd) exposure on testicular mineral bioavailability, activity of antioxidant enzymes, testicular structure and germ cells ultrastructure Main methods: Cadmium chloride was administered in a single dose to thirty rats equally randomized into five groups: Saline, 0.9% NaCl; Cd1 – Cd4, 0.67, 0.74, 0.86 and 1.1 mg Cd/kg. Seven days after Cd exposure, animals were euthanized and testes were collected for biochemical analysis, as well as light, scanning and transmission electron microscopy. Key findings: Cadmium exposure induced dose‐dependent testicular toxicity. Tubular and intertubular compartments were targets of Cd and calcium (Ca) deposits, marked structural and ultrastructural pathologic remodeling, and a reduced distribution of iron, selenium, magnesium, copper, zinc and total protein. Despite upregulation in antioxidant enzyme activities (i.e. catalase [CAT] and superoxide dismutase [SOD]), morphologic and molecular testis damage such as protein oxidation was not prevented, especially with higher doses of Cd. As non‐degenerated tissue areas also presented Ca deposits, Ca imbalance was not only a consequence but also a cause of Cd‐induced testis toxicity and germ cell death Significance: Taken together, our findings indicated that Cd exposition induced dose‐dependent testicular dystrophic calcification, which was associated with increased antioxidant enzymes activity and protein oxidation, mineral imbalance, germ cell calcification and death in rats. Although increased CAT and SOD activity represents a counter‐regulatory reaction to cadmium‐induced toxicity, this reaction is insufficient to prevent testicular pathological remodeling.

Swimming training attenuates the morphological reorganization of the myocardium and local inflammation in the left ventricle of growing rats with untreated experimental diabetes.

Diabetic cardiomyopathy is associated with cardiac remodeling, myocardial dysfunction, low-grade inflammation, and reduced cardiac adiponectin in patients with type 1 diabetes mellitus (T1DM). Alternatively, physical exercise is an important strategy for the management of diabetes. This study aimed to investigate the influence of low-intensity swimming training in cardiac cytokines, structural remodeling, and cardiomyocyte contractile dysfunction in growing rats with untreated experimental DM. Thirty-day-old male Wistar rats were divided into four groups (n=14, per group): sedentary control (SC), exercised control (EC), sedentary diabetic (SD), and exercised diabetic (ED). Diabetes was induced by streptozotocin (60 mg kg(-1), i.p.). Animals from exercised groups swam (5 days/week, 90 min/day, loading up to 5% body weight around the animals chest) for 8 weeks. The left ventricle (LV) was removed for molecular, morphological, and cardiomyocyte mechanical analysis. Diabetic animals presented cardiac remodeling with myocardial histoarchitectural disorganization, fibrosis, and necrosis. The capillary density was lower in diabetic animals. LV cardiomyocytes from diabetic animals exhibited more prolonged time to the peak of contraction and time to half relaxation than those from control animals. The cardiac levels of interleukin 10, nitric oxide, and total and high molecular weight (HMW) adiponectin were significantly decreased in diabetic animals. Exercise training reduced the level of TNF-α, increased capillary density, and attenuated the histopathological parameters assessed in diabetic rats. In conclusion, the cardiac structural remodeling coexists with reduced levels of total and HMW adiponectin, inflammation, and cardiomyocyte contractility dysfunction in experimental DM. More important, low-intensity swimming training attenuates part of these pathological changes, indicating the beneficial role for exercise in untreated T1DM.

Quantificação de fatores de crescimento na pele de equinos tratada com plasma rico em plaquetas

ABSTRACT.- Souza M.V., Pinto J.O., Costa M.M., Santos E.C., Garcia S.L.R. & Oliveira L.L. 2014. [Quantification of growth factors in horse skin treated with platelet-rich plasma . ] Quantificacao de fatores de crescimento na pele de equinos tratada com plasma rico em plaquetas . Pesquisa Veterinaria Brasileira 34(6):599-612 . Departamento de Veterinaria, Universidade Federal de Vicosa, Campus Universitario s/n, Vicosa, MG 36570-000, Brazil. E-mail: msouza@ufv.brPlatelet-rich plasma (PRP) is a product derived from total blood centrifugation, rich in bioactive factors, such as growth factors. Despite largely used in healing processes, there is a controversy whether the therapy is effective in promoting skin healing. The objective of this study was to quantify and compare the concentrations of the factors TGF-β1 and PDGF-BB in PRP, blood plasma and skin, at different phases of the healing process of skin treated or not with PRP. Seven healthy crossbred 16 to 17-year-old geldings (16.14±0.63) were used. Three quadrangular-shaped lesions (6.25cm