Involvement of M1 and M3 receptors in isolated pancreatic islets function during weight cycling in ovariectomized rats.

We investigated the structural and functional adaptations of the pancreas during weight cycling in animals submitted to hypoestrogenism. Female Wistar rats were distributed among the following test groups: ShamAL (AL, ad libitum); OVXAL (ovariectomized); and OVXcycle (dietary restriction with weight cycling). The ShamAL and OVXAL groups received commercial feed ad libitum, whereas the OVXcycle group received 21 days of commercial feed ad libitum, and 21 days of caloric restriction, with caloric intake amounting to 40% of the amount of feed consumed by the rats in the OVXAL group. The tolerance tests for glucose and insulin were applied. After euthanasia, the pancreas and adipose tissue were collected. The disappearance of glucose during the insulin assay occurred at a higher rate in tissues from the OVXcycle group, compared with the OVXAL group. Fasting glycemia and perirenal adipose tissue were lower in the OVXcycle group. By comparison with the ShamAL and OVXAL groups, the OVXcycle group showed higher protein expression of the M1 and M3 receptors and SOD1-2, as well as higher carbachol-induced insulin secretion. Under highly stimulatory conditions with 16.7 mmol/L glucose, the OVXAL and OVXcycle groups presented lower insulin secretion compared with the ShamAL group. Morphological analysis revealed higher iron deposition in the OVXAL islets by comparison with the OVXcycle group. These results show that ovariectomy accelerated the loss of pancreatic islet function, and that weight cycling could restore the function of the islets.

Argon Atmospheric Plasma Treatment Promotes Burn Healing by Stimulating Inflammation and Controlling the Redox State.

Burns are a public health problem, with second-degree burns as one of the most common types. Although intense inflammation worsens burn healing, effective therapies are scarce. Thus, infections and hypertrophic scars may occur, which compromise patient quality of life and may delay healing. Argon atmospheric plasma (AP) has been shown to positively influence wound healing. In the context of identifying effective and alternative therapies for the treatment of second-degree burns, the present study evaluated AP in the treatment of second-degree burns in rats compared to that for sham treatment on the 2nd, 7th, 14th, and 21st days post-injury. Our results revealed proinflammatory effect for AP by recruiting predominantly neutrophils on the 7th day and macrophages on the 21st day compared to sham treatment, allowing a greater production of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-17, and also controlled the inflammation by IL-10 and transforming growth factor (TGF)-ß1. AP also showed antioxidant activity important for controlling oxidative damage on the 2nd day. This favored the induction of angiogenesis from the 2nd day and induction fibroplasia and fibrillogenesis after the 14th day, which enhanced burn healing with the formation of a thinner burn eschar before the 21st day post-burn. Thus, AP effectively modulated the inflammatory phase of second-degree burn healing through the control of oxidative damage that favored the following phases. Therefore, AP is a relevant alternative in the treatment of second-degree burns.

Liver metabolic changes induced by conjugated linoleic acid in calorie-restricted rats.

OBJECTIVE: Complexes like conjugated linoleic acid (CLA) reduce the percentage of body fat by increasing energy expenditure, fat oxidation, or both. The aim of this study was to verify if CLA is able to mimic caloric restriction (CR), and determine the effects of CLA on liver metabolic profile of young adult male Wistar rats. MATERIALS AND METHODS: We divided 36 animals into the following groups: 1) Control; 2) CLA (1% of daily food intake, 21 days, orogastric intubation); 3) Restr (fed 60% of the diet offered to controls); and 4) CLA Restr. Liver tissues were processed for biochemical and molecular or mitochondrial isolation (differential centrifugation) and blood samples were collected for biochemical analyses. RESULTS: Treatment of the animals for 21 days with 1% CLA alone or combined with CR increased liver weight and respiration rates of liver mitochondria suggesting significant mitochondrial uncoupling. We observed a decrease in adipose tissue leading to insulin resistance, hyperinsulinemia, and hepatic steatosis due to increased liver cholesterol and triacylglycerol levels, but no significant effects on body mass. The expression of hepatic cellular connexins (43 and 26) was significantly higher in the CLA group compared with the Control or Restr groups. CONCLUSION: CLA does not seem to be a safe compound to induce mass loss because it upregulates the mRNA expression of connexins and induces hepatic mitochondrial changes and lipids disorders.

Vitamin E and caloric restriction promote hepatic homeostasis through expression of connexin 26, N-cad, E-cad and cholesterol metabolism genes.

Connexins (Cx) and cadherins are responsible for cell homeostasis. The Cx activity is directly related to cholesterol. The present work investigates whether vitamin E, with or without caloric restriction (CR), alters the mRNA expression of Cx26, Cx32, Cx43, N-cadherins (N-cads), E-cadherins (E-cads) and alpha-smooth muscle actin (α-SMA), and evaluates their relation to cholesterol metabolism in rat liver. Animals were divided into different groups: control with ad libitum diet (C), control+vitamin E (CV), aloric restriction with intake to 60% of group C (CR), and the intake of group CR+vitamin E (RV). There were increases of manganese superoxide dismutase (Mn-SOD) and glutathione S-transferase mu 1, indicating antioxidant effects of CR and vitamin E. An increase of nitric oxide in the CR group was in agreement with the Mn-SOD data. Supplementation with vitamin E, with or without CR, upregulated the expression of Cx26 mRNA and increased low-density lipoprotein cholesterol (LDL-c) in the CV group. Reductions of Cx32 and Cx43 were associated with lower LDL-c. Increases in Hmgcr and low-density lipoprotein receptor (LDLr) in the CV and RV groups could be explained by the effect of vitamin E. A reduction of LDLr in the CR group was due to the reduced dietary intake. Increases in cadherins in the CV, CR and RV groups were indicative of tissue maintenance, which was also supported by increases of α-SMA in groups CV and RV. Finally, vitamin E, with or without CR, increased Cx26, probably modulated by expression of the Hmgcr and LDLr genes. This suggests important relationship of Cxs and cholesterol metabolism genes.

Evolution of Periodontal Disease: Immune Response and RANK/RANKL/OPG System.

The aim of this study was to evaluate markers of bone loss and immune response present in evolution of periodontal disease. One hundred and two Wistar rats were divided into three animals groups: PD0, without ligation and PD15 days and PD60 days, submitted to ligation placement with a sterile 3-0 silk cord in the cervical region of the upper first molar on both sides. Samples were obtained from the gingival tissue for histomorphometric analysis, immunohistochemical analysis of RANK, RANKL, OPG, characterization of the inflammatory infiltrate, quantification of nitric oxide, MCP-1, RANTES, IP10 chemokines, and expression of the TGF-b1, VEG, and bFGF. The number of inflammatory cells in gingival tissue was higher in PD60 samples. The collagen content and the area occupied by birefringent collagen fibers were lower for PD60. Differential leukocyte counting showed that there was a significantly higher polymorphonuclear influx in group PD15, while PD60 showed a greater number of lymphocytes. PD60 showed higher RANTES, IP-10, MCP-1 gene transcripts, as well as a higher nitric oxide concentration. Clinical evaluation revealed that the PD60 group presented an increase in furcal area. In conclusion, in this animal model the increase of RANK/RANKL and HGF markers is related to a specific immune response, and probably contributed to the evolution of periodontal disease. Investigating the effect of these biomarkers can help in targeted therapy for bone resorption, since blocking these can inhibit bone loss.

Liver metabolic changes induced by conjugated linoleic acid in calorie-restricted rats

ABSTRACT Objective Complexes like conjugated linoleic acid (CLA) reduce the percentage of body fat by increasing energy expenditure, fat oxidation, or both. The aim of this study was to verify if CLA is able to mimic caloric restriction (CR), and determine the effects of CLA on liver metabolic profile of young adult male Wistar rats. Materials and methods We divided 36 animals into the following groups: 1) Control; 2) CLA (1% of daily food intake, 21 days, orogastric intubation); 3) Restr (fed 60% of the diet offered to controls); and 4) CLA Restr. Liver tissues were processed for biochemical and molecular or mitochondrial isolation (differential centrifugation) and blood samples were collected for biochemical analyses. Results Treatment of the animals for 21 days with 1% CLA alone or combined with CR increased liver weight and respiration rates of liver mitochondria suggesting significant mitochondrial uncoupling. We observed a decrease in adipose tissue leading to insulin resistance, hyperinsulinemia, and hepatic steatosis due to increased liver cholesterol and triacylglycerol levels, but no significant effects on body mass. The expression of hepatic cellular connexins (43 and 26) was significantly higher in the CLA group compared with the Control or Restr groups. Conclusion CLA does not seem to be a safe compound to induce mass loss because it upregulates the mRNA expression of connexins and induces hepatic mitochondrial changes and lipids disorders.

Evolution of Periodontal Disease: Immune Response and RANK/RANKL/OPG System

Abstract The aim of this study was to evaluate markers of bone loss and immune response present in evolution of periodontal disease. One hundred and two Wistar rats were divided into three animals groups: PD0, without ligation and PD15 days and PD60 days, submitted to ligation placement with a sterile 3-0 silk cord in the cervical region of the upper first molar on both sides. Samples were obtained from the gingival tissue for histomorphometric analysis, immunohistochemical analysis of RANK, RANKL, OPG, characterization of the inflammatory infiltrate, quantification of nitric oxide, MCP-1, RANTES, IP10 chemokines, and expression of the TGF-b1, VEG, and bFGF. The number of inflammatory cells in gingival tissue was higher in PD60 samples. The collagen content and the area occupied by birefringent collagen fibers were lower for PD60. Differential leukocyte counting showed that there was a significantly higher polymorphonuclear influx in group PD15, while PD60 showed a greater number of lymphocytes. PD60 showed higher RANTES, IP-10, MCP-1 gene transcripts, as well as a higher nitric oxide concentration. Clinical evaluation revealed that the PD60 group presented an increase in furcal area. In conclusion, in this animal model the increase of RANK/RANKL and HGF markers is related to a specific immune response, and probably contributed to the evolution of periodontal disease. Investigating the effect of these biomarkers can help in targeted therapy for bone resorption, since blocking these can inhibit bone loss.

Resumo Este estudo avaliou marcadores de perda óssea e da resposta imune presentes na evolução da doença periodontal. Cento e dois ratos Wistar foram divididos em três grupos de animais: PD0, sem ligadura e PD15 dias e PD60 dias, submetidos a colocação de ligadura com um fio de seda estéril 3-0 na região cervical do primeiro molar superior em ambos os lados. Foram obtidas amostras de tecido gengival para análise histomorfométrica, análises imunohistoquímicas de RANK, RANKL, OPG, caracterização do infiltrado inflamatório, quantificação de óxido nítrico, expressão de quimiocinas MCP-1, RANTES, IP10 e do TGF-b1, VEGF e bFGF . O número de células inflamatórias no tecido gengival foi maior nas amostras PD60. O teor de colágeno na área ocupada pelas fibras de colágeno birrefringentes foram menores para PD60. A contagem diferencial de leucócitos mostrou que houve um influxo polimorfonuclear significativamente maior no grupo PD15, enquanto que PD60 mostrou número maior de linfócitos. PD60 apresentou transcritos de genes RANTES, IP-10, MCP-1 mais elevados, bem como uma maior concentração de óxido nítrico. A avaliação clínica revelou que o grupo PD60 apresentou aumento da área óssea exposta na região da furca. Em conclusão, neste modelo animal o aumento dos marcadores RANK/RANKL e HGF está relacionado a uma resposta imunológica específica e provavelmente contribuiu para a evolução da doença periodontal. Investigar o efeito destes biomarcadores pode ajudar na terapia dirigida para a reabsorção óssea, uma vez que bloquear estes pode inibir a perda óssea.

Polymorphism in the SIRT1 gene and parameters of metabolic syndrome in a sample of the adult Brazilian population / Estudo de polimorfismo no gene SIRT1 e parâmetros da síndrome metabólica em uma amostra da população brasileira adulta

ABSTRACT Objective: To evaluate whether the single nucleotide polymorphism rs7895833 (A/G) of the gene SIRT1 is associated with metabolic syndrome criteria in a sample of Brazilian adults. Methods: Serum samples and oral mucosal cells were collected from 243 subjects aged 30 to 70 years. Biochemical, hormonal, and anthropometric data were obtained. The single nucleotide polymorphism rs7895833 (A/G) was analyzed by polymerase chain reaction using the amplification refractory mutation system. Results: Among the 243 study subjects, 100 (41.15%) were classified as non-metabolic syndrome and 143 (58.85%), as metabolic syndrome. The frequency of the single nucleotide polymorphism rs7895833 (A/G) did not differ between the groups. However, 111 patients (45.67%) were overweight (body mass index: 25-29.9 kg/m2). Blood glucose, total cholesterol, triglycerides, very low density lipoprotein, low density lipoprotein, waist and hip circumferences, and blood pressure were higher in the metabolic syndrome group than in the non-metabolic syndrome group. Free thyroxine 4, grown hormone, and insulin levels were within the normal range. The metabolic conditions of the patients with metabolic syndrome indicate biochemical, anthropometric, and hormonal changes characteristic of overweight and obesity. Conclusion: The SIRT1 polymorphism rs7895833 (A/G) is not associated with the metabolic syndrome in the adult Brazilian population.

RESUMO Objetivo: Avaliar se o polimorfismo de nucleotídeo único rs7895833 (A/G) do gene SIRT1 está associado à síndrome metabólica em uma amostra da população brasileira. Foram coletadas, de 243 indivíduos com idades entre 30 e 70 anos, amostras de soro e de células da mucosa bucal. Métodos: Dosagens bioquímicas, hormonais e dados antropométricos foram analisados. O polimorfismo de nucleotídeo único rs7895833 (A/G) foi analisado por sistema de amplificação de mutação por refração - reação em cadeia da polimerase. Resultados: Entre os 243 indivíduos estudados, 100 (41,15%) foram classificados como não apresentando síndrome meta-bólica e 143 (58,85%) como apresentando a síndrome. Não houve diferença significativa na frequência do polimorfismo de nucleotídeo único rs7895833 (A/G) entre os grupos. No entanto, 111 pacientes (45,67%) estavam com sobrepeso (índice de massa corporal: 25-29,9 kg/m2). Glicose, colesterol total, triglicerídeos, lipoproteínas de muito baixa densidade, lipoproteínas de baixa densidade, circunferência da cintura e do quadril e pressão arterial foram maiores no grupo com síndrome metabólica quando comparado ao outro grupo. Tiroxina 4 livre, hormônio do crescimento e os níveis de insulina estavam no valor de referência. As condições metabólicas dos pacientes com síndrome metabólica indicam alterações bioquímicas, antropométricas e hormonais características do excesso de peso e da obesidade. Conclusão: Sugerimos que o polimorfismo rs7895833 (A/G), no gene SIRT1, não esteja associado à síndrome metabólica na população adulta brasileira.