Systemic and local inflammatory response after implantation of biomaterial in critical bone injuries.

PURPOSE: To evaluate inflammatory response in critical bone injuries after implantation of the biomaterial composed of hydroxyapatite (HA)/poly (lactic-coglycolic acid) (PLGA)/BLEED. METHODS: Forty-eight male Wistar rats (280 ± 20 grams) were divided into two groups: control group (CG), in which the animals do not receive any type of treatment; and biomaterial group (BG), in which the animals received the HA/PLGA/BLEED scaffold. Critical bone injury was induced in the medial region of the skull calotte with the aid of a trephine drill 8 mm in diameter. The biomaterial was implanted in the form of 1.5-mm thick scaffolds. Serum and calotte were collected at one, three and seven days. RESULTS: Biomaterial had a significant effect on the morphological structure of the bone, accelerating osteoblast activation within three days, without causing exacerbated systemic inflammation. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that BG induced upregulation of osteogenic genes such as runt-related transcription factor 2, and stimulated genes of inflammatory pathways such as tumor necrosis factor-α, on the first day without overexpressing genes related to bone matrix degradation, such as tissue inhibitor of metalloproteinases-1 and matrix metalloproteinase-9. CONCLUSIONS: The HA/PLGA/BLEED® association can be used as a bone graft to aid bone repair, as it is capable of modulating expression of important genes at this stage of the repair process.

Carbon Black CB-EDA Nanoparticles in Macrophages: Changes in the Oxidative Stress Pathway and in Apoptosis Signaling.

The influence of black carbon nanoparticles on J774.A1 murine cells was investigated with the objective of exploring the cytotoxicity of black carbon functionalized with ethylenediamine CB-EDA. The results showed that CB-EDA has a cytotoxic profile for J774.A1 macrophages in a time- and dose-dependent manner. When phagocytosed by the macrophage, CB-EDA triggers a mechanism that leads to apoptosis. In this process, there is an increase in oxidative stress pathways due to the activation of nitric oxide and then ROS. This causes an imbalance in redox function and a disruption of membrane integrity that occurs due to high levels of LDH, in addition to favoring the release of the pro-inflammatory cytokines IL-6, IL-12, and tumor necrosis factor (TNF) in an attempt to modulate the cell. However, these stimuli are not sufficient to repair the cell and the level of mitochondrial integrity is affected, causing a decrease in cell viability. This mechanism may be correlated with the activation of the caspasse-3 pathway, which, when compromised, cleaves and induces cells death via apoptosis, either through early or late apoptosis. In view of this, the potential for cell damage was investigated by analyzing the oxidative and inflammatory profile in the macrophage lineage J774.A1 and identifying potential mechanisms and metabolic pathways connected to these processes when cells were exposed to NP CB-EDA for both 24 h and 48 h.

Systemic and local inflammatory response after implantation of biomaterial in critical bone injuries

ABSTRACT Purpose: To evaluate inflammatory response in critical bone injuries after implantation of the biomaterial composed of hydroxyapatite (HA)/poly (lactic-coglycolic acid) (PLGA)/BLEED. Methods: Forty-eight male Wistar rats (280 ± 20 grams) were divided into two groups: control group (CG), in which the animals do not receive any type of treatment; and biomaterial group (BG), in which the animals received the HA/PLGA/BLEED scaffold. Critical bone injury was induced in the medial region of the skull calotte with the aid of a trephine drill 8 mm in diameter. The biomaterial was implanted in the form of 1.5-mm thick scaffolds. Serum and calotte were collected at one, three and seven days. Results: Biomaterial had a significant effect on the morphological structure of the bone, accelerating osteoblast activation within three days, without causing exacerbated systemic inflammation. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that BG induced upregulation of osteogenic genes such as runt-related transcription factor 2, and stimulated genes of inflammatory pathways such as tumor necrosis factor-α, on the first day without overexpressing genes related to bone matrix degradation, such as tissue inhibitor of metalloproteinases-1 and matrix metalloproteinase-9. Conclusions: The HA/PLGA/BLEED® association can be used as a bone graft to aid bone repair, as it is capable of modulating expression of important genes at this stage of the repair process.

Experimental type 2 diabetes induction reduces serum vaspin, but not serum omentin, in Wistar rats.

Vaspin and omentin are adipose tissue adipokines that have often been related to obesity and its comorbidities. The aim of this study was to investigate the behaviour of serum omentin and vaspin in models of type 2 diabetes. To do this, Wistar rats (~200 g) were randomly divided into two groups: a non-diabetic group (n = 6) and a diabetic group fed on a high-fat diet (n = 6) and a low dose of streptozotocin (Sigma® ). All procedures were approved by the Brazilian Ethics Committee. Body weight (BW) and food intake were recorded daily. Tail blood glucose levels were assessed at the end of the diabetes induction period. The insulin tolerance test (ITT) was performed after the diabetes induction period (7 weeks). The serum and tissues (liver, pancreas, and retroperitoneal (RET), epididymal (EPI) and visceral (VIS) white adipose tissues) were immediately removed and weighed. Analyses of levels of insulin, omentin, vaspin, adiponectin and inflammatory cytokines IL-6, IL-8 (CXCL8), TNF-α and C-reactive protein (CRP) in serum were performed using the enzyme-linked immunosorbent assay (ELISA). Our results showed that IL-8 and CRP serum levels in the diabetic group were significantly higher than in the non-diabetic group. Vaspin and adiponectin values were lower for the diabetic group than for the non-diabetic group. Omentin, IL-6 and TNF-α values did not differ between the groups. Our results showed that both the metabolism of the adipose tissue and the secretion of adipokines may be affected in diabetic rats. Omentin showed no difference between the groups, although the vaspin values decreased in the diabetic group.

Toxocara canis and the allergic process.

The protective effect of infectious agents against allergic reactions has been thoroughly investigated. Current studies have demonstrated the ability of some helminths to modulate the immune response of infected hosts. The objective of the present study was to investigate the relationship between Toxocara canis infection and the development of an allergic response in mice immunised with ovalbumin (OVA). We determined the total and differential blood and bronchoalveolar lavage fluid cells using BALB/c mice as a model. To this end, the levels of interleukin (IL)-4, IL-5 and IL-10 and anti-OVA-IgE were measured using an ELISA. The inflammatory process in the lungs was observed using histology slides stained with haematoxylin and eosin. The results showed an increase in the total number of leukocytes and eosinophils in the blood of infected and immunised animals at 18 days after infection. We observed a slight lymphocytic inflammatory infiltrate in the portal space in all infected mice. Anti-OVA-IgE levels were detected in smaller proportions in the plasma of immunised and infected mice compared with mice that were only infected. Therefore, we concluded that T. canis potentiates inflammation in the lungs in response to OVA, although anti-OVA-IgE levels suggest a potential reduction of the inflammatory process through this mechanism.

Toxocara canis and the allergic process

The protective effect of infectious agents against allergic reactions has been thoroughly investigated. Current studies have demonstrated the ability of some helminths to modulate the immune response of infected hosts. The objective of the present study was to investigate the relationship between Toxocara canis infection and the development of an allergic response in mice immunised with ovalbumin (OVA). We determined the total and differential blood and bronchoalveolar lavage fluid cells using BALB/c mice as a model. To this end, the levels of interleukin (IL)-4, IL-5 and IL-10 and anti-OVA-IgE were measured using an ELISA. The inflammatory process in the lungs was observed using histology slides stained with haematoxylin and eosin. The results showed an increase in the total number of leukocytes and eosinophils in the blood of infected and immunised animals at 18 days after infection. We observed a slight lymphocytic inflammatory infiltrate in the portal space in all infected mice. Anti-OVA-IgE levels were detected in smaller proportions in the plasma of immunised and infected mice compared with mice that were only infected. Therefore, we concluded that T. canis potentiates inflammation in the lungs in response to OVA, although anti-OVA-IgE levels suggest a potential reduction of the inflammatory process through this mechanism.

Chemical composition, characterization of anthocyanins and antioxidant potential of Euterpe edulis fruits: applicability on genetic dyslipidemia and hepatic steatosis in mice / Composición química y caracterización de antocianinas y potencial antioxidante de la fruta euterper edulis: aplicabilidad en la dislipidemia genética y la esteatosis hepática en ratones

The significance of polyphenol intake for the prevention of chronic diseases is controversial. Objective: this study investigated the chemical composition and antioxidant potential of an anthocyanin-rich extract from Euterpe edulis fruits (LPEF) and its effects on liver steatosis in dyslipidemic apoE-/- knockout mice. Materials and methods: mice were divided into G1 (C57BL/6) standard diet; G2 (apoE-/-) standard diet, G3 (apoE-/-) 2% LPEF, G4 (apoE-/-) 6% LPEF, G5 (apoE-/-) 10% LPEF, G6 (apoE-/-) 2% α-tocopherol acetate. After 75 days of treatment, the animals were euthanized. The LPEF contained a high level of monomeric anthocyanins (301.4 mg/100g) and marked antioxidant activity. Results: Catalase activity was reduced in G3, G4, G5 and G6 compared to G2. Superoxide dismutase was reduced only in G4. The animals in G4, G5, and G6 showed low HDL and triglycerides levels compared to G2. The proportion of lipid droplets in liver tissue was reduced in G4 and G5 compared to G2, G3, and G6. Conclusion: The results indicated that E. edulis pulp is rich in anthocyanins and the LPEF dietary consumption can reduce the severity of liver steatosis in apoE-/- mice, an effect that is potentially mediated by the antioxidant activity of this extract and modulation of triglyceride serum levels (AU)

El papel de los polifenoles en la prevención de enfermedades crónicas es controvertido. Objetivo: este estudio investigó la composición química y el potencial antioxidante de un extracto del fruto de Euterpe edulis rico en antocianinas (LPEF) y sus efectos en la esteatosis hepática en ratones apoE-/- knockout con dislipidemia. Material y métodos: los ratones fueron divididos en los siguientes grupos; G1 (C57BL/6) con una dieta estándar; G2 (apoE-/-) con dieta estándar; G3 G3 (apoE-/-) con 2% de LPEF; G4 (apoE-/-) con 6% de LPEF; G5 (apoE-/-) con 10% de LPEF y G6 (apoE-/-) con 2% acetato α-tocoferol (α-tocopherol acetate). Después de 75 días de tratamiento, los animales fueron eutanizados. El LPEF contenía un alto nivel de antocianinas monoméricas (301,4 mg/100 g) con notable actividad antioxidante. Resultados: la actividad catalasa fue reducida en los grupos G3, G4, G5 y G6 comparada con G2. La superoxidasa dismutasa solo se redujo en el grupo G4. Los animales de G4, G5 y G6 mostraron bajos niveles de HDL triglicéridos, comparados con G2. La proporción de lípidos en el tejido hepático fue reducida en G4 y G5, comparado con G2, G3 y G6. Conclusión: los resultados indicaron que la pulpa de E. edulis es rica en antocianinas, y que el consumo de LPEF en la dieta puede reducir la severidad de la esteatosis hepática en ratones apoE-/-, un efecto que es potencialmente mediado por la actividad antioxidante de este extracto y la modulación en los niveles séricos de triglicéridos (AU)

Morfologia e contratilidade em cardiomiócitos de ratos com baixo desempenho para o exercício físico / Morphology and contractility in cardiomyocytes of rats with low exercise performance

FUNDAMENTO: A capacidade aeróbica é fundamental para o desempenho físico, e a baixa capacidade aeróbica está relacionada ao desencadeamento de diversas doenças cardiovasculares. OBJETIVO: Comparar a contratilidade e a morfologia de cardiomiócitos isolados de ratos com baixo desempenho e desempenho padrão para o exercício físico. MÉTODOS: Ratos Wistar, com 10 semanas de idade, foram submetidos a um protocolo de corrida em esteira até a fadiga, e foram divididos em dois grupos: Baixo Desempenho (BD) e Desempenho Padrão (DP). Em seguida, após eutanásia, o coração foi removido rapidamente e, por meio de dissociação enzimática, os cardiomiócitos do ventrículo esquerdo foram isolados. O comprimento celular e dos sarcômeros e a largura dos cardiomiócitos foram medidos usando-se um sistema de detecção de bordas. Os cardiomiócitos isolados foram estimulados eletricamente a 1 e 3 Hz e a contração celular foi medida registrando-se a alteração do seu comprimento. RESULTADOS: O comprimento celular foi menor no grupo BD (157,2 ± 1,3µm; p < 0,05) em relação ao DP (161,4 ± 1,3 µm), sendo o mesmo resultado observado para o volume dos cardiomiócitos (BD, 25,5 ± 0,4 vs. DP, 26,8 ± 0,4 pL; p < 0,05). Os tempos para o pico de contração (BD, 116 ± 1 vs. DP, 111 ± 2ms) e para o relaxamento total (BD, 143 ± 3 vs. DP, 232 ± 3 ms) foram maiores no grupo BD. CONCLUSÃO: Conclui-se que os miócitos do ventrículo esquerdo dos animais de baixo desempenho para o exercício físico apresentam menores dimensões que os dos animais de desempenho padrão, além de apresentarem perdas na capacidade contrátil.

BACKGROUND: Aerobic capacity is essential to physical performance, and low aerobic capacity is related to the triggering of various cardiovascular diseases. OBJECTIVE: To compare the morphology and contractility of isolated rat cardiomyocytes with low performance and standard performance for exercise. METHODS: Wistar rats with 10 weeks of age underwent a protocol of treadmill running to fatigue, and were divided into two groups: Low Performance (LP) and Standard Performance (SP). Then, the animals were sacrificed, the heart was quickly removed and, by means of enzymatic dissociation, left ventricular cardiomyocytes were isolated. The cell and sarcomeres length and width of cardiomyocytes were measured using an edge detection system. The isolated cardiomyocytes were electrically stimulated at 1 and 3 Hz and cell contraction was measured by registering the change of their length. RESULTS: The cell length was shorter in the LP group (157.2 1.3µm; p < 0.05) compared to SP (161.4 1.3µm), and the same result was observed for the volume of cardiomyocytes (LP, 25.5 0.4. vs. SP, 26.8 ± 0.4 pL; p < 0.05). The time to peak contraction (LP, 116 1 vs. SP 111 2ms) and total relaxation (LP, 143 3 vs. SP 232 3ms) were higher in the LP group. CONCLUSION: We conclude that left ventricular myocytes of animals with low performance for exercise are smaller than animals with standard performance. In addition to that, they present losses in contractile capacity.

Morphology and contractility in cardiomyocytes of rats with low exercise performance.

BACKGROUND: Aerobic capacity is essential to physical performance, and low aerobic capacity is related to the triggering of various cardiovascular diseases. OBJECTIVE: To compare the morphology and contractility of isolated rat cardiomyocytes with low performance and standard performance for exercise. METHODS: Wistar rats with 10 weeks of age underwent a protocol of treadmill running to fatigue, and were divided into two groups: Low Performance (LP) and Standard Performance (SP). Then, the animals were sacrificed, the heart was quickly removed and, by means of enzymatic dissociation, left ventricular cardiomyocytes were isolated. The cell and sarcomeres length and width of cardiomyocytes were measured using an edge detection system. The isolated cardiomyocytes were electrically stimulated at 1 and 3 Hz and cell contraction was measured by registering the change of their length. RESULTS: The cell length was shorter in the LP group (157.2 ± 1.3 µm; p < 0.05) compared to SP (161.4 ± 1.3 µm), and the same result was observed for the volume of cardiomyocytes (LP, 25.5 ± 0.4 vs. SP, 26.8 ± 0.4 pL; p < 0.05). The time to peak contraction (LP, 116 ± 1 vs. SP 111 ± 2 ms) and total relaxation (LP, 143 ± 3 vs. SP 232 ± 3 ms) were higher in the LP group. CONCLUSION: We conclude that left ventricular myocytes of animals with low performance for exercise are smaller than animals with standard performance. In addition to that, they present losses in contractile capacity.