Calcium and magnesium urinary excretion in dairy cows with different fee of glucose metabolization / Excreção urinária de cálcio e magnésio em vacas leiteiras com diferentes taxas de metabolização de glicose

Background: The post-partum period in dairy cows is accompanied by a low glucose metabolism in adipose tissue and skeletal muscle tissue, being glucose conducted to the milk production. In humans, low glucose metabolism is associated with metabolic syndromes, the high glucose levels reduce tubular reabsorption of Magnesium (Mg) and Calcium (Ca), leading to hypomagnesemia and hypocalcemia. These minerals are important to the dairy cow, as their decrease leads to diseases. The aim of this study was to evaluate the relationship between glucose metabolism rate with the urinary excretion of Ca and Mg in multiparous dairy cows during the post-partum period.Materials, Methods & Results: Twenty dairy cows were used from a commercial farm southern Brazil, in the semi-extensive system. Glucose tolerance tests were performed (TTG) on day 9 relative to calving. The cows were categorized into three groups according to the glucose metabolism rate (area under the glucose curve, glucose half-life and glucose consumption rate): High Glucose Metabolization (GA); Intermediate Glucose Metabolizing (GI); and Low Glucose Metabolization (GL). Blood and urine samples were collected on days 0, + 3, + 6, + 9, +16 and +23 in relation to calving for to determine the levels of Ca, Mg, insulin (Ins), non-esterified fatty acids (NEFA) and Glu. In urine was evaluated the excretion of Ca and Mg. The cows were milked twice a day (at 3:00 a.m. and 3:00 p.m.) and the milk yield (kg/cow) was recorded daily and averages were generated every five days from day 15 to day 60 postpartum. The statistical analyses were performed with the MIXED procedure to assess the main effect of group, time (in days) and their interaction by using version 9.2 SAS software.[...]

Calcium and magnesium urinary excretion in dairy cows with different fee of glucose metabolization / Excreção urinária de cálcio e magnésio em vacas leiteiras com diferentes taxas de metabolização de glicose

Background: The post-partum period in dairy cows is accompanied by a low glucose metabolism in adipose tissue and skeletal muscle tissue, being glucose conducted to the milk production. In humans, low glucose metabolism is associated with metabolic syndromes, the high glucose levels reduce tubular reabsorption of Magnesium (Mg) and Calcium (Ca), leading to hypomagnesemia and hypocalcemia. These minerals are important to the dairy cow, as their decrease leads to diseases. The aim of this study was to evaluate the relationship between glucose metabolism rate with the urinary excretion of Ca and Mg in multiparous dairy cows during the post-partum period.Materials, Methods & Results: Twenty dairy cows were used from a commercial farm southern Brazil, in the semi-extensive system. Glucose tolerance tests were performed (TTG) on day 9 relative to calving. The cows were categorized into three groups according to the glucose metabolism rate (area under the glucose curve, glucose half-life and glucose consumption rate): High Glucose Metabolization (GA); Intermediate Glucose Metabolizing (GI); and Low Glucose Metabolization (GL). Blood and urine samples were collected on days 0, + 3, + 6, + 9, +16 and +23 in relation to calving for to determine the levels of Ca, Mg, insulin (Ins), non-esterified fatty acids (NEFA) and Glu. In urine was evaluated the excretion of Ca and Mg. The cows were milked twice a day (at 3:00 a.m. and 3:00 p.m.) and the milk yield (kg/cow) was recorded daily and averages were generated every five days from day 15 to day 60 postpartum. The statistical analyses were performed with the MIXED procedure to assess the main effect of group, time (in days) and their interaction by using version 9.2 SAS software.[...](AU)

Efeito do treinamento intervalado de alta intensidade no desempenho em teste de esforço / Effect of high intensity interval training in performance stress test

The high-intensity interval training (HIIT) is characterized by vigorous and intermittent performing certain exercise separated by periods of passive or active rest with low intensity. This training model can be as effective as continuous endurance training. However, the aim of this study was to investigate the effect of HIIT in fitness, in addition to checking the lactate curve and glycemic variation in maximal exercise test (MET). For this, used were 8 male Wistar rats on a treadmill adapted for rodents for two weeks. To determine the intensity of the animals were subjected to TEM before the start of training and subsequently refreshed every two weeks. It HAS consists of steps 3 minutes of running with constant load, followed by two minutes of passive rest. At each stage there was an increase of 0.3 km / h to exhaustion of the animal and determine the lactate threshold. Blood samples (25 µL) were performed during rest, with the help of capillary calibrated with EDTA. Immediately after collecting the blood was transferred to eppendorf tube containing 50 µL of sodium fluoride for subsequent analysis lactimeter YSI 2300 STAT plus. The glucose analysis pre and post TEM was performed with the aid of reactive tapes and analyzed Accu-Chek ACTIVE®. After a certain MET, the animals were submitted to HIIT, which consisted of five minutes of warming, followed by four shots at 80% of maximum capacity followed by passive rest, finishing with five minute cool down. This study was approved by the Ethics Committee on Animal Use (CEUA) of the State University of Ceará (UECE) by the number 2542310/2015. For analysis of the linearity of lactate curves was carried out Pearson's correlation for all MET. We used the analysis of variance (ANOVA - two way) followed by Bonferroni post test to check differences in pre and post glucose MET. In all cases the significance level was preset at p <0.05. An increase in the physical condition of the animals, where the maximum speed obtained in the first MET was 1.94 ± 0.12 and 3.95 ± 0.24 after 8 weeks of HIIT with Pearson linear correlation was significant in all MET . This is due to ATP production by anaerobic glycolytic system result in the accumulation of pyruvate and NADH in the muscle, which subsequently forms the lactate. In glycemic analysis it was found that in the first TEM there was a significant increase in postworkout blood glucose (pre=119±19, post=170±19), possibly by increased activation of the adrenergic system inducing hepatic glycogenolysis. In TEM 5 there was a significant reduction in blood glucose after TEM (pre=137±15, post=130±21) can be explained by increased phosphorylation of GLUT4, increasing glucose uptake by muscle exercise. Therefore, HIIT was able to increase physical ability of animals to give an increasing curve of lactate in all MET and distinct variations in glycaemia.

Efeito do treinamento intervalado de alta intensidade no desempenho em teste de esforço / Effect of high intensity interval training in performance stress test

The high-intensity interval training (HIIT) is characterized by vigorous and intermittent performing certain exercise separated by periods of passive or active rest with low intensity. This training model can be as effective as continuous endurance training. However, the aim of this study was to investigate the effect of HIIT in fitness, in addition to checking the lactate curve and glycemic variation in maximal exercise test (MET). For this, used were 8 male Wistar rats on a treadmill adapted for rodents for two weeks. To determine the intensity of the animals were subjected to TEM before the start of training and subsequently refreshed every two weeks. It HAS consists of steps 3 minutes of running with constant load, followed by two minutes of passive rest. At each stage there was an increase of 0.3 km / h to exhaustion of the animal and determine the lactate threshold. Blood samples (25 µL) were performed during rest, with the help of capillary calibrated with EDTA. Immediately after collecting the blood was transferred to eppendorf tube containing 50 µL of sodium fluoride for subsequent analysis lactimeter YSI 2300 STAT plus. The glucose analysis pre and post TEM was performed with the aid of reactive tapes and analyzed Accu-Chek ACTIVE®. After a certain MET, the animals were submitted to HIIT, which consisted of five minutes of warming, followed by four shots at 80% of maximum capacity followed by passive rest, finishing with five minute cool down. This study was approved by the Ethics Committee on Animal Use (CEUA) of the State University of Ceará (UECE) by the number 2542310/2015. For analysis of the linearity of lactate curves was carried out Pearson's correlation for all MET. We used the analysis of variance (ANOVA - two way) followed by Bonferroni post test to check differences in pre and post glucose MET. In all cases the significance level was preset at p <0.05. An increase in the physical condition of the animals, where the maximum speed obtained in the first MET was 1.94 ± 0.12 and 3.95 ± 0.24 after 8 weeks of HIIT with Pearson linear correlation was significant in all MET . This is due to ATP production by anaerobic glycolytic system result in the accumulation of pyruvate and NADH in the muscle, which subsequently forms the lactate. In glycemic analysis it was found that in the first TEM there was a significant increase in postworkout blood glucose (pre=119±19, post=170±19), possibly by increased activation of the adrenergic system inducing hepatic glycogenolysis. In TEM 5 there was a significant reduction in blood glucose after TEM (pre=137±15, post=130±21) can be explained by increased phosphorylation of GLUT4, increasing glucose uptake by muscle exercise. Therefore, HIIT was able to increase physical ability of animals to give an increasing curve of lactate in all MET and distinct variations in glycaemia.(AU)

Aerobic cyanide degradation by bacterial isolates from cassava factory wastewater

Ten bacterial strains that utilize cyanide (CN) as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM) and glucose (0.2% w/v). The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters..(AU)

Optimization of growth and bacteriocin production by Lactobacillus sakei subsp. sakei2a

Lactobacillus sakei subsp. sakei 2a is a bacteriocinogenic lactic acid bacterium isolated from Brazilian pork sausage, capable of inhibiting the growth of microbial pathogens, mainly Listeria monocytogenes. In order to optimize bacteriocin production for industrial applications, this study evaluated the effect of supplementation of MRS broth with glucose, Tween 20, Tween 80, sodium citrate, potassium chloride and cysteine, and effect of the initial pH and temperature of incubation of the medium on production of bacteriocins by L. sakei 2a. Adding glucose and Tween 20 to the medium, an initial pH of 5.0 or 5.5, and incubation temperatures of 25 °C or 30 °C resulted to the highest bacteriocin yields. Thus, a 2⁴ factorial design with the four variables was performed, and statistical analysis showed that it was an adequate model (R² = 0.8296). In the studied range, the four parameters significantly influenced bacteriocin production, with the maximum yield produced at an initial pH between 5.5 and 7.0, a temperature between 25 and 30 °C and supplementation of the MRS broth with glucose from 3.25 to 6.0 g L⁻¹ and Tween 20 from 0.575 to 1.15% (v/v). Response Surface Methodology analysis indicated that the highest bacteriocin production (12800 AU mL⁻¹) occurred in the MRS broth supplemented with 5.5 g L⁻¹ glucose and 1.05% Tween 20 at an initial pH of 6.28 and an incubation temperature of 25 °C. The amount of bacteriocin produced in commercial MRS broths under the same conditions was only 5600AU mL⁻¹..(AU)

Análise da influência do treinamento intervalado de alta intensidade nos marcadores lactato e glicose sanguíneos em ratos Wistar / Analysis of high intensity interval training influence markers in blood glucose and lactate in Wistar rats

Physical exercise has been shown to be an important means of prevention and treatment against many diseases. One factor is always highlighted the intensity of the activity. This study used an adapted protocol of high intensity interval training. Were evaluated biomarkers lactate and glucose. This study was approved by the Ethics Committee for the Use of Animals from the State University of Ceará registered under number 2542310/2015. The animals were previously adapted for 10 days with increasing speed up to 0.8km / h. The stress tests were done in steps of 3 minutes of intense activity for 2 minutes of rest. After determining the maximum capacity of the animal was made the training consisted of a 2 minute activity at 80% of maximum, followed by 4 minutes of rest. Before and after each exercise period, blood samples were collected for lactate tests, samples for glucose testing were collected just before the activity and after completion of all speed tests. They were obtained as results the increase of lactate and glucose levels in the post exercise. The lactate values and ranged from 0.5 mmol / L at rest and increased to an average of 1.7 mmol / L in 2.0 km / h. Blood glucose values were 120 mg / dL to about 170 mg / dl after training. Thereby indicating that the protocol used took the animals to a stress level higher than the rest, possibly due to intense physical activity.

Análise da influência do treinamento intervalado de alta intensidade nos marcadores lactato e glicose sanguíneos em ratos Wistar / Analysis of high intensity interval training influence markers in blood glucose and lactate in Wistar rats

Physical exercise has been shown to be an important means of prevention and treatment against many diseases. One factor is always highlighted the intensity of the activity. This study used an adapted protocol of high intensity interval training. Were evaluated biomarkers lactate and glucose. This study was approved by the Ethics Committee for the Use of Animals from the State University of Ceará registered under number 2542310/2015. The animals were previously adapted for 10 days with increasing speed up to 0.8km \ h. The stress tests were done in steps of 3 minutes of intense activity for 2 minutes of rest. After determining the maximum capacity of the animal was made the training consisted of a 2 minute activity at 80% of maximum, followed by 4 minutes of rest. Before and after each exercise period, blood samples were collected for lactate tests, samples for glucose testing were collected just before the activity and after completion of all speed tests. They were obtained as results the increase of lactate and glucose levels in the post exercise. The lactate values and ranged from 0.5 mmol / L at rest and increased to an average of 1.7 mmol / L in 2.0 km / h. Blood glucose values were 120 mg / dL to about 170 mg / dl after training. Thereby indicating that the protocol used took the animals to a stress level higher than the rest, possibly due to intense physical activity.(AU)

Pork loin two-toning and drip loss in relation to steak cross-section anatomical position, plasma and exudate glucose

Perception of color and its relationship to water holding capacity are important for defining the yield and quality of the pork production process. The aim of this study was to identify the relationship among color measurements taken at various anatomical positions in the cross-sectional surface of pork loin steak, and measurements of fluid exudation and its glucose concentration, as well as the impact on these attributes due to plasma glucose at slaughter. Two assays were conducted sequentially: i) investigation of the surface color parameters at different anatomical positions in the pork loin cross-section and their relationship to general exudation; and ii) the effect of plasma glucose levels on surface color variables, drip loss and glucose exudate concentration in three anatomical regions in the steak. The L* value of the ventro-lateral region, in the first assay, had the highest correlation with average steak drip loss at all anatomical points, exudation increasing proportionally between 48 and 72 h. The hue angle was also positively correlated with drip loss and lightness. The drip loss was greater when the animals had high plasma glucose, especially in the intermediate and lateral regions of the steak surface. The intermediate region presented greater lightness and lower redness. The plasma and glucose exudate concentrations, potential indicators of the muscle glycolytic metabolism, were related to color and drip loss. These variables can be influenced by the anatomical region inside the muscle, impacting the ability to retain water, two-toning occurrence and overall pork loin quality.

Pork loin two-toning and drip loss in relation to steak cross-section anatomical position, plasma and exudate glucose

Perception of color and its relationship to water holding capacity are important for defining the yield and quality of the pork production process. The aim of this study was to identify the relationship among color measurements taken at various anatomical positions in the cross-sectional surface of pork loin steak, and measurements of fluid exudation and its glucose concentration, as well as the impact on these attributes due to plasma glucose at slaughter. Two assays were conducted sequentially: i) investigation of the surface color parameters at different anatomical positions in the pork loin cross-section and their relationship to general exudation; and ii) the effect of plasma glucose levels on surface color variables, drip loss and glucose exudate concentration in three anatomical regions in the steak. The L* value of the ventro-lateral region, in the first assay, had the highest correlation with average steak drip loss at all anatomical points, exudation increasing proportionally between 48 and 72 h. The hue angle was also positively correlated with drip loss and lightness. The drip loss was greater when the animals had high plasma glucose, especially in the intermediate and lateral regions of the steak surface. The intermediate region presented greater lightness and lower redness. The plasma and glucose exudate concentrations, potential indicators of the muscle glycolytic metabolism, were related to color and drip loss. These variables can be influenced by the anatomical region inside the muscle, impacting the ability to retain water, two-toning occurrence and overall pork loin quality.(AU)

Canthaxanthin biosynthesis by Dietzia natronolimnaea HS-1: effects of inoculation and aeration rate

The interest in production of natural colorants by microbial fermentation has been currently increased. The effects of D-glucose concentration (3.18-36.82 g/L), inoculum size (12.5 x 10(9)-49.5 x 10(9) cfu cells/mL) and air-flow rate (1.95-12.05 L/L min) on the biomass, total carotenoid and canthaxanthin (CTX) accumulation of Dietzia natronolimnaea HS-1 in a batch bioreactor was scrutinized using a response surface methodology-central composite rotatable design (RSM-CCRD). Second-order polynomial models with high R² values ranging from 0.978 to 0.990 were developed for the studied responses using multiple linear regression analysis. The models showed the maximum cumulative amounts of biomass (7.85 g/L), total carotenoid (5.48 mg/L) and CTX (4.99 mg/L) could be achieved at 23.38 g/L of D-glucose, 31.2 x 10(9) cfu cells/mL of inoculation intensity and air-flow rate of 7.85 L/L min. The predicted values for optimum conditions were in good agreement with experimental data.

Effects of sciatic nerve transection on glucose uptake in the presence and absence of lactate in the frog dorsal root ganglia and spinal cord / Efeito da secção do nervo isquiático sobre a captação de glicose na presença e ausência de lactato em gânglio da raiz dorsal e medula espinhal de rãs

Frogs have been used as an alternative model to study pain mechanisms because the simplicity of their nervous tissue and the phylogenetic aspect of this question. One of these models is the sciatic nerve transection (SNT), which mimics the clinical symptoms of “phantom limb”, a condition that arises in humans after amputation or transverse spinal lesions. In mammals, the SNT increases glucose metabolism in the central nervous system, and the lactate generated appears to serve as an energy source for nerve cells. An answerable question is whether there is elevated glucose uptake in the dorsal root ganglia (DRG) after peripheral axotomy. As glucose is the major energy substrate for frog nervous tissue, and these animals accumulate lactic acid under some conditions, bullfrogs Lithobates catesbeianus were used to demonstrate the effect of SNT on DRG and spinal cord 1-[14C] 2-deoxy-D-glucose (14C-2-DG) uptake in the presence and absence of lactate. We also investigated the effect of this condition on the formation of 14CO2 from 14C-glucose and 14C-L-lactate, and plasmatic glucose and lactate levels. The 3-O-[14C] methyl-D-glucose (14C-3-OMG) uptake was used to demonstrate the steady-state tissue/medium glucose distribution ratio under these conditions. Three days after SNT, 14C-2-DG uptake increased, but 14C-3-OMG uptake remained steady. The increase in 14C-2-DG uptake was lower when lactate was added to the incubation medium. No change was found in glucose and lactate oxidation after SNT, but lactate and glucose levels in the blood were reduced. Thus, our results showed that SNT increased the glucose metabolism in the frog DRG and spinal cord. The effect of lactate on this uptake suggests that glucose is used in glycolytic pathways after SNT.(AU)

As rãs são usadas como modelos experimentais alternativos no estudo da nocicepção, tanto pela simplicidade do seu tecido nervoso como por permitirem uma abordagem filogenética sobre o tema. Um desses modelos é a secção do nervo isquiático (SNI), o qual simula os sintomas clínicos do “membro fantasma”, uma condição que ocorre nos humanos após amputação ou secção completa da medula espinal. Em mamíferos, a SNI aumenta o metabolismo da glicose no sistema nervoso central, e o lactato é uma fonte energética para as células nervosas. Porém é desconhecido se essa é a situação em gânglio da raiz dorsal (GRD). Como a glicose é o principal substrato energético para o tecido nervoso de rãs, e a concentração plasmática de lactato está aumentada nesses animais em distintas situações, a rã-touro Lithobates catesbeianus foi usada para demonstrar os efeitos da SNI sobre a captação de 1-[14C] 2-deoxi-D-glicose (14C-2-DG), na presença e ausência de lactato, em GRD e medula espinal. Foram demonstrados ainda os efeitos dessa condição experimental sobre a formação de 14CO2 a partir de 14C-glicose e 14C-L-lactato, e a concentração plasmática de glicose e lactato. A captação de 3-O-[14C] metil-D-glicose (14C-3-OMG) foi usada para demonstrar a relação tecido/meio estável da glicose nessas condições. A captação de 14C-2-DG aumentou três dias após a SNI, sem qualquer alteração na captação de 14C-3-OMG. O aumento foi reduzido quando o lactato foi acrescentado ao meio de incubação. A taxa de oxidação da glicose e do lactato não modificou após SNI, mas houve redução na concentração plasmática de glicose e lactato. Assim, a SNI aumenta o metabolismo da glicose no GRD e medula espinal de rãs. Os efeitos do lactato sobre essa captação sugerem o uso da glicose na via glicolítica após a SNI.(AU)

Yeast HXK2 gene reverts glucose regulation mutation of penicillin biosynthesis in P. chrysogenum

The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent.

Insulina e captação de glicose no corpo lúteo canino / Insulin and glucose uptake in canine corpus luteum

O diestro é a fase luteínica na cadela caracterizada pelo aumento de progesterona (P4) sérica na primeira metade e por flutuações de 17β-estradiol (E2) na segunda metade. O corpo lúteo (CL) é uma glândula endócrina temporária, que passa por um processo de desenvolvimento, manutenção e regressão, atingindo atividade secretória plena quando sua formação está completa. A insulina é o hormônio anabólico essencial para a manutenção da homeostase de glicose e do crescimento e diferenciação celular, sendo secretado pelas células β pancreáticas. A sinalização intracelular da insulina começa com a sua ligação a um receptor de membrana específico, o que desencadeia uma série de ações metabólicas. Sabe-se que uma das consequências desta ligação é a translocação de transportadores de glicose 4 (GLUT4; gene SLC2A4) para que ocorra a captação de glicose. Nosso grupo demonstrou a expressão de GLUT4 no corpo lúteo de cadelas, expressão esta regulada diferencialmente ao longo do diestro. A presença deste transportador levou-nos a hipotetizar que a insulina seja importante para regulação da função luteínica. [...] Esses resultados apontam a insulina, bem como o IL6 e o NFKB como fatores importantes que desempenham um papel na função do CL canino e trazem o CL para o grupo de tecidos que respondem ao estímulo insulínico aumentando a expressão de GLUT4 e consequentemente a captação de glicose. Além disso, estes eventos parecem sofrer controle adicional pelos hormônios esteróides

Diestrus is the luteal phase in dogs characterized by an increase in progesterone (P4) levels in the first half and fluctuations of 17β-estradiol (E2) in the second half. The corpus luteum (CL) is a temporary endocrine gland, which undergoes a process of development, maintenance and regression, reaching full secretory activity when its formation is complete. Insulin is an anabolic hormone essential for the maintenance of glucose homeostasis, cell growth and differentiation, and is secreted by pancreatic beta cells. Intracellular signaling of insulin begins with its binding to a specific membrane receptor, which triggers a series of metabolic actions. It is known that one consequence of this connection is the translocation of glucose transporters 4 (GLUT4; gene SLC2A4) for glucose uptake. Our group demonstrated the expression of GLUT4 in the canine corpus luteum in a time-related manner throughout diestrus. The presence of this transporter led us to hypothesize that insulin is important for the regulation of luteal function.[…] These results point towards a regulatory function 14 exerted by insulin, IL6 and NFKB in the canine CL and place this organ among the insulin sensitive ones, which respond to insulin stimuli increasing GLUT4 expression and glucose uptake. Moreover, these events seems to undergo a further control by steroid hormones

Insulina e captação de glicose no corpo lúteo canino / Insulin and glucose uptake in canine corpus luteum

O diestro é a fase luteínica na cadela caracterizada pelo aumento de progesterona (P4) sérica na primeira metade e por flutuações de 17β-estradiol (E2) na segunda metade. O corpo lúteo (CL) é uma glândula endócrina temporária, que passa por um processo de desenvolvimento, manutenção e regressão, atingindo atividade secretória plena quando sua formação está completa. A insulina é o hormônio anabólico essencial para a manutenção da homeostase de glicose e do crescimento e diferenciação celular, sendo secretado pelas células β pancreáticas. A sinalização intracelular da insulina começa com a sua ligação a um receptor de membrana específico, o que desencadeia uma série de ações metabólicas. Sabe-se que uma das consequências desta ligação é a translocação de transportadores de glicose 4 (GLUT4; gene SLC2A4) para que ocorra a captação de glicose. Nosso grupo demonstrou a expressão de GLUT4 no corpo lúteo de cadelas, expressão esta regulada diferencialmente ao longo do diestro. A presença deste transportador levou-nos a hipotetizar que a insulina seja importante para regulação da função luteínica. [...] Esses resultados apontam a insulina, bem como o IL6 e o NFKB como fatores importantes que desempenham um papel na função do CL canino e trazem o CL para o grupo de tecidos que respondem ao estímulo insulínico aumentando a expressão de GLUT4 e consequentemente a captação de glicose. Além disso, estes eventos parecem sofrer controle adicional pelos hormônios esteróides (AU)

Diestrus is the luteal phase in dogs characterized by an increase in progesterone (P4) levels in the first half and fluctuations of 17β-estradiol (E2) in the second half. The corpus luteum (CL) is a temporary endocrine gland, which undergoes a process of development, maintenance and regression, reaching full secretory activity when its formation is complete. Insulin is an anabolic hormone essential for the maintenance of glucose homeostasis, cell growth and differentiation, and is secreted by pancreatic beta cells. Intracellular signaling of insulin begins with its binding to a specific membrane receptor, which triggers a series of metabolic actions. It is known that one consequence of this connection is the translocation of glucose transporters 4 (GLUT4; gene SLC2A4) for glucose uptake. Our group demonstrated the expression of GLUT4 in the canine corpus luteum in a time-related manner throughout diestrus. The presence of this transporter led us to hypothesize that insulin is important for the regulation of luteal function.[…] These results point towards a regulatory function 14 exerted by insulin, IL6 and NFKB in the canine CL and place this organ among the insulin sensitive ones, which respond to insulin stimuli increasing GLUT4 expression and glucose uptake. Moreover, these events seems to undergo a further control by steroid hormones (AU)