Browsing by Subject "Glucagon"

Now showing 1 - 7 of 7
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    Evaluation of CART-, glucagon-, and insulinimmunoreactive cells in the pancreas of an experimental rat model of unilateral renal artery stenosis
    (F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2015) Kasacka, I.; Janiuk, I.; Piotrowska, Z.
    Hypertension is one of the most frequently occurring diseases worldwide. Approximately 10% of the population with hypertension reveal the secondary type of hypertension. The aim of this study was to evaluate the cells containing CART, insulin and glucagon in the pancreas of rats with renovascular hypertension. An experimental model of hypertension in rats according to Goldblatt (2K1C model of hypertension) was used in the study. The experimental material (pancreas) was collected in the 6th week of the study. Cells containing CART, insulin and glucagon were evaluated using immunohistochemical and morphometric methods. Pancreatic islet cells were evaluated based on the number and intensity of staining. The investigation showed an increase in the number and immunoreactivity of CART containing cells, 6 weeks after partial unilateral ligation of the renal artery. There was a significant decrease in the number of glucagon-IR cells. Although intensity of staining these cells did not change. No differences were observed in the number and staining affinity of insulin-containing cells. On the basis of the study it can be stated that the endocrine system of pancreas undergoes changes in the course of renovascular hypertension. This may affect the production of hormones and contribute to the development of possible hypertension complications.
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    Glycogen autophagy in the liver and heart of newborn rats. The effects of glucagon, adrenalin or rapamycin
    (Murcia : F. Hernández, 2005) Kondomerkos, D.J.; Kalamidas, Stefanos; Kotoulas, Othon B.; Hann, A.C.
    The effects of glucagon, adrenalin or rapamycin on glycogen autophagy in the liver and heart of newborn rats were studied using biochemical determinations and electron microscopy. Glucagon or adrenalin increased autophagic activity in the hepatocytes and myocardiocytes, glycogen-hydrolyzing acid glucosidase activity in the liver and heart and degradation of glycogen inside the autophagic vacuoles. Glucagon or adrenalin also increased the maltosehydrolyzing acid glucosidase activity in the liver, but not in the heart. Similar effects were produced in the newborn heart by rapamycin. These observations support previous studies suggesting that the cellular machinery which controls glycogen autophagy in the liver and heart of newborn animals, is regulated by the cyclic AMP and the mTOR pathways.
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    Metabolic profile and glycemic response in fully-grown sows born using assisted reproductive technologies
    (Elsevier, 2024-10-02) Cánovas Bernabé, Sebastián; Heras García, Sonia; Romero Aguirregomezcorta, Jon; Quintero Moreno, Armando Arturo; Gadea Mateos, Joaquín; Coy Fuster, Pilar; Romar Andrés, Raquel; Anatomía y Anatomía Patológica Comparada; Facultad de Veterinaria
    The aim of the present work was to gain insight into the metabolism of pigs derived from assisted reproductive technologies during their adulthood. Approximately 4h after feeding, a blood sample was taken from 3.5 year old sows born by artificial insemination (AI group, n = 7) and transfer of in vitro produced embryos (IVP group, n = 11) to determine the physiological concentrations of the main biomarkers of carbohydrates (glucose and lactate), proteins (albumin, creatinine and urea) and lipids (cholesterol and triglycerides). Four weeks later, an oral glucose tolerance test (OGTT; 1.75g glucose/kg body weight) was performed after an overnight fast and 1h of water withdrawal. Blood samples were obtained prior (T = 0 min; fasting conditions) and 15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min after glucose intake. At each time point, glycemia was measured immediately using glucometer test strips, and serum was collected to determine the above metabolites along with insulin and glucagon. After OGTT, the area under the curve (AUC) between sampling times and homeostasis model assessment of insulin resistance (HOMA) indices were calculated. Under physiological conditions, the concentration of metabolites studied was similar between AI and IVP sows. In both groups, fasting decreased cholesterol and increased triglycerides and urea (P < 0.001). However, creatinine and lactate were similar in both groups under physiological and fasting conditions. The expected increase in albuminemia and decrease in glycaemia after fasting was only observed in IVP sows. OGTT revealed a different glucose curve pattern (monophasic in AI and biphasic in IVP group), a lower mean concentration of cholesterol, glucose, lactate, triglycerides in IVP compared to AI pigs (P < 0.01), and a higher mean concentration of albumin, creatinine and insulin in IVP compared to AI group (P < 0.05). On the contrary, no differences were found between groups for mean serum glucagon and urea levels, nor for glucose homeostasis indices HOMA-IR and HOMA-%B. The AUC differed between groups at several time points with larger AUC for creatinine, and smaller AUC for glucose, glucagon, and triglycerides, in IVP pigs than in AI pigs at 180–210 min (P < 0.05). In conclusion, under physiological conditions the metabolic profile of fully-grown AI and IVP sows is similar and within normal ranges. Glucose challenge revealed differences in metabolic and insulin responses between groups but with normal glucose tolerance in both cases.
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    Open Access
    Metabolic profile and glycemic response in fully-grown sows born using assisted reproductive technologies
    (Elsevier, 2024-10-02) Cánovas, Sebastián; Heras, S.; Quintero-Moreno, A.A.; Gadea, Joaquín; Coy, P.; Romar, Raquel; Romero Aguirregomezcorta, Jon; Fisiología
    The aim of the present work was to gain insight into the metabolism of pigs derived from assisted reproductive technologies during their adulthood. Approximately 4h after feeding, a blood sample was taken from 3.5 year old sows born by artificial insemination (AI group, n = 7) and transfer of in vitro produced embryos (IVP group, n = 11) to determine the physiological concentrations of the main biomarkers of carbohydrates (glucose and lactate), proteins (albumin, creatinine and urea) and lipids (cholesterol and triglycerides). Four weeks later, an oral glucose tolerance test (OGTT; 1.75g glucose/kg body weight) was performed after an overnight fast and 1h of water withdrawal. Blood samples were obtained prior (T = 0 min; fasting conditions) and 15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min after glucose intake. At each time point, glycemia was measured immediately using glucometer test strips, and serum was collected to determine the above metabolites along with insulin and glucagon. After OGTT, the area under the curve (AUC) between sampling times and homeostasis model assessment of insulin resistance (HOMA) indices were calculated. Under physiological conditions, the concentration of metabolites studied was similar between AI and IVP sows. In both groups, fasting decreased cholesterol and increased triglycerides and urea (P < 0.001). However, creatinine and lactate were similar in both groups under physiological and fasting conditions. The expected increase in albuminemia and decrease in glycaemia after fasting was only observed in IVP sows. OGTT revealed a different glucose curve pattern (monophasic in AI and biphasic in IVP group), a lower mean concentration of cholesterol, glucose, lactate, triglycerides in IVP compared to AI pigs (P < 0.01), and a higher mean concentration of albumin, creatinine and insulin in IVP compared to AI group (P < 0.05). On the contrary, no differences were found between groups for mean serum glucagon and urea levels, nor for glucose homeostasis indices HOMA-IR and HOMA-%B. The AUC differed between groups at several time points with larger AUC for creatinine, and smaller AUC for glucose, glucagon, and triglycerides, in IVP pigs than in AI pigs at 180–210 min (P < 0.05). In conclusion, under physiological conditions the metabolic profile of fully-grown AI and IVP sows is similar and within normal ranges. Glucose challenge revealed differences in metabolic and insulin responses between groups but with normal glucose tolerance in both cases.
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    Publication
    Open Access
    Metabolic profile and glycemic response in fully-grown sows born using assisted reproductive technologies
    (Elsevier, 2024-10-02) Canovas, Sebastian; Heras, Sonia; Quintero-Moreno, Armando; Gadea, Joaquin; Coy, Pilar; Romar, Raquel; Romero Aguirregomezcorta, Jon; Fisiología
    The aim of the present work was to gain insight into the metabolism of pigs derived from assisted reproductive technologies during their adulthood. Approximately 4h after feeding, a blood sample was taken from 3.5 year old sows born by artificial insemination (AI group, n = 7) and transfer of in vitro produced embryos (IVP group, n = 11) to determine the physiological concentrations of the main biomarkers of carbohydrates (glucose and lactate), proteins (albumin, creatinine and urea) and lipids (cholesterol and triglycerides). Four weeks later, an oral glucose tolerance test (OGTT; 1.75g glucose/kg body weight) was performed after an overnight fast and 1h of water withdrawal. Blood samples were obtained prior (T = 0 min; fasting conditions) and 15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min after glucose intake. At each time point, glycemia was measured immediately using glucometer test strips, and serum was collected to determine the above metabolites along with insulin and glucagon. After OGTT, the area under the curve (AUC) between sampling times and homeostasis model assessment of insulin resistance (HOMA) indices were calculated. Under physiological conditions, the concentration of metabolites studied was similar between AI and IVP sows. In both groups, fasting decreased cholesterol and increased triglycerides and urea (P < 0.001). However, creatinine and lactate were similar in both groups under physiological and fasting conditions. The expected increase in albuminemia and decrease in glycaemia after fasting was only observed in IVP sows. OGTT revealed a different glucose curve pattern (monophasic in AI and biphasic in IVP group), a lower mean concentration of cholesterol, glucose, lactate, triglycerides in IVP compared to AI pigs (P < 0.01), and a higher mean concentration of albumin, creatinine and insulin in IVP compared to AI group (P < 0.05). On the contrary, no differences were found between groups for mean serum glucagon and urea levels, nor for glucose homeostasis indices HOMA-IR and HOMA-%B. The AUC differed between groups at several time points with larger AUC for creatinine, and smaller AUC for glucose, glucagon, and triglycerides, in IVP pigs than in AI pigs at 180–210 min (P < 0.05). In conclusion, under physiological conditions the metabolic profile of fully-grown AI and IVP sows is similar and within normal ranges. Glucose challenge revealed differences in metabolic and insulin responses between groups but with normal glucose tolerance in both cases.
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    Open Access
    Preliminary results on glycaemic response after oral glucose tolerance test (OGTT) in sows derived from assisted reproductive technologies
    (Association of Embryo Technology in Europe, 2023) Quintero-Moreno, Armando; Canovas, Sebastian; Heras, Sonia; Gadea, Joaquin; Romar, Raquel; Romero Aguirregomezcorta, Jon; Fisiología
    In human, murine and rabbit species, individuals derived from embryos produced in vitro (IVP) may present, among others, disorders in glucose metabolism (Chen et al. 2014, Diabetes 63:3189–3,98; García-Domínguez et al. 2020, Animals 10:1043-1059). In pigs, available information is very scarce and we have reported in 45-days-old piglets differences in the glycaemic response after an oral glucose tolerance test (OGTT) between IVP-produced animals and those conceived in vivo by artificial insemination (AI) (Paris-Oller et al. 2022, JDOHaD 13:593-605). However, it is unknown if these differences are corrected or maintained during adult life. The objective of the present study was to evaluate the glucose tolerance in the same colony of pigs during their adult life by means of an oral glucose tolerance test (OGTT). The animals were obtained from a previous study (Paris-Oller et al. 2021, J Anim Sci Biotech 12:32-44) that were born after artificial insemination (AI group) and surgical transfer of in vitro-produced embryos (IVP group). All animals were kept under same housing and feeding conditions since birth. The OGTT was performed in AI (n=8) and IVP (n=10) sows with 3.5-3.6 years age, and weighing from 227 to 249 kg. For the OGTT, animals were previously fasting for 24h and 2h without drinking water. Sows ingested 1.75 g/kg body weight of glucose solution (100% glucose carbs, Myprotein) and blood samples were collected via auricular vein before OGTT (t=0) and over 240 minutes (15, 30, 45, 60, 90, 120, 150, 180, 210 and 240 min) following glucose administration. Blood glucose concentration was immediately measured by a glucometer (Aposan) using test strips, and blood serum was obtained and freeze (-80ºC) until determination of insulin (immunoturbidimetric method) and glucagon (10-1281-01 Mercodia, Uppsala, Sweden). Data were analysed using an ANOVA test with nested design (animal within reproductive treatment group) and reproductive treatment (AI, ET) and time of sampling and interaction treatment and time as the main factors. Data are expressed as mean ± SEM. Values of p<0.05 were considered significant. Glycaemia was influenced by time of sampling (p=0.019) and was higher in AI-derived animals than in IVP group (66.95±1.29 vs. 60.57±1.31 g/dL, p<0.001), while the interaction group and time was not significant (p=0.401). On the other hand, the insulin concentration was only influenced by the origin of the animals, with higher values in IVP than AI animals (58.66±4.88 vs. 75.79±4.27 μUI/ml, p=0.013). As for the glucagon concentration, it was similar for all the times of sampling and between groups (AI: 2.84±0.39 vs. IVP: 2.75±0.24 pmol/L, p=0.664). These observations suggest that, up to some extend, the differences in the response to OGTT in IVP-produced pigs are maintained during their adult life. Moreover, IVP sows challenged with an OGTT show changes in the insulin response. Increasing the number of animals, and determination of complementary biochemical parameters are needed for a better interpretation of the results.
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    The effect of glucagon and cyclic adenosine monophosphate on acute liver damage induced by acetaminophen
    (F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2013) Kelava, Tomislav; Ćavar, Ivan; Vukojevic, Katarina; Saraga-Babić, Mirna; Čulo, Filip
    Recent investigations suggest that glucagon might have a potentially important hepatoprotective activity. We investigated the effect of glucagon in a model of acetaminophen-induced liver injury. CBA male mice were injected intraperitoneally with a lethal (300 mg/kg) or sublethal (150 mg/kg) dose of acetaminophen. The liver injury was assessed by observing the survival of mice, by liver histology and by measuring the concentration of alanine-aminotransferase (ALT). Inducible nitric oxide synthase (iNOS) and nuclear factor kappa B (NF-κB) protein expressions were determined immunohistochemically. Hepatic levels of reduced glutathione (GSH) and cyclic adenosine monophosphate (cAMP) were also measured. Results show that glucagon, dose and time dependently, protects against acetaminophen-induced hepatotoxicity. This protection was achieved with a dose of 0.5 mg/kg of glucagon given intraperitoneally 15 min before or 1 h after acetaminophen. Treatment of animals with acetaminophen elevated ALT and nitrite/nitrate concentration in the plasma, enhanced iNOS and NF-κB expression and reduced GSH and cAMP concentration in the liver. Animals treated with glucagon had higher hepatic cAMP level, lower ALT and nitrite/nitrate concentration in plasma and lower expression of iNOS in liver cells than animals in control group, whereas there was no difference in the expression of NF-κB. Glucagon did not prevent the loss of GSH content caused by acetaminophen. Our investigation indicates that glucagon has a moderately protective effect against acetaminophen-induced liver injury, which is, at least partially, mediated through the downregulation of iNOS and through the increase in hepatic cAMP content, but it is not mediated through the modulation of NF-κB activity.