Induction of lactation in dairy heifers: milk production, inflammatory and metabolic aspects / Indução de lactação em novilhas leiteiras: produção de leite, aspectos inflamatórios e metabólicos

The aim of this study was to evaluate the metabolic, inflammatory, and hepatic aspects, as well as the milk yield in heifers submitted to protocol for induction of lactation compared to primiparous cows. Sixty Holstein heifers were selected and enrolled into two groups: Control (n= 30), pregnant heifers and Induction heifers (n= 30), non-pregnant femeales, submitted to a lactation induction protocol. Blood samples were collected at: pre-lactation period (weeks -3, -2 and -1) and post-lactation period (weeks 1, 2 and 3), aiming to evaluate glucose, non-esterified fatty acids, paraoxonase-1, albumin, ALT, GGT and cortisol. The protocol efficiently induced lactation in all the heifers, which produced 74.54% of the total production of milk from primiparous cows. In the pre-lactation period, induced animals presented higher concentrations of non-esterified fatty acids than the Control heifers, and the opposite was observed in the post lactation period. In both moments albumin and ALT were lower in the Induction group, and paraoxonase-1 activity and GGT concentrations were higher, compared to the Control. Thus, lactation induction protocol is efficient to initiate milk production in dairy heifers with no considerable changes in energetic, metabolic and hepatic profile when compared to heifers in physiological lactation.(AU)

O objetivo deste estudo foi avaliar os perfis metabólico, inflamatório, hepático e a produção de leite de novilhas induzidas à lactação comparadas a primíparas. Sessenta novilhas da raça Holandês foram selecionadas e alocadas em grupos: controle (n=30), novilhas prenhas, e indução (n=30), novilhas vazias submetidas a um protocolo de indução de lactação. As amostras de sangue foram coletadas nas semanas -3, -2 e -1 (pré-lactação) e nas semanas 1, 2 e 3 (pós-início de lactação) para avaliação de glicose, ácidos graxos não esterificados, paraoxonase-1, albumina, ALT, GGT e cortisol. O protocolo induziu eficientemente a lactação em todas as novilhas, que produziram 74,54% da produção total de leite do controle. No período pré-lactação, o grupo indução apresentou maiores concentrações de ácidos graxos não esterificados que o controle, e o oposto foi observado pós-lactação. Em ambos os momentos, albumina e ALT foram menores no grupo indução, e a atividade da paraoxonase-1 e as concentrações de GGT foram maiores, em comparação ao controle. Assim, o protocolo de indução de lactação foi eficiente para iniciar a produção de leite em novilhas induzidas, além de terem sido observadas alterações nos perfis energético, metabólico e hepático em comparação a novilhas em lactação fisiológica.(AU)

Bats and zoonotic viruses: can we confidently link bats with emerging deadly viruses?

An increasingly asked question is 'can we confidently link bats with emerging viruses?'. No, or not yet, is the qualified answer based on the evidence available. Although more than 200 viruses - some of them deadly zoonotic viruses - have been isolated from or otherwise detected in bats, the supposed connections between bats, bat viruses and human diseases have been raised more on speculation than on evidence supporting their direct or indirect roles in the epidemiology of diseases (except for rabies). However, we are convinced that the evidence points in that direction and that at some point it will be proved that bats are competent hosts for at least a few zoonotic viruses. In this review, we cover aspects of bat biology, ecology and evolution that might be relevant in medical investigations and we provide a historical synthesis of some disease outbreaks causally linked to bats. We provide evolutionary-based hypotheses to tentatively explain the viral transmission route through mammalian intermediate hosts and to explain the geographic concentration of most outbreaks, but both are no more than speculations that still require formal assessment.

Efecto de la ingesta aguda de vanillina sobre la resistencia insulínica en humanos / Effect of a single oral dose of vanillin on insulin resistance in humans

Background: NADPH oxidase is a source of reactive oxygen species that may contribute to insulin resistance (IR). Aim: To assess the effect of a single oral dose of vanillin (a putative inhibitor of the enzyme) on IR in humans. Material and Methods: Using a crossover, random, double-blind design, eight lean and 10 obese males ingested 600 mg of vanillin or placebo followed by the ingestion of 75g of glucose. Serum/plasma glucose, free-fatty acids, insulin, glutathione, C reactive protein concentrations and red blood cell glutathione concentration were determined. Insulin resistance was estimated by the Matsuda index. Results: Under fasting conditions, obese individuals had higher glucose and insulin and lower red blood cell glutathione levels than their lean counterparts (p < 0.01). Serum free-fatty acids, total and oxidized plasma glutathione concentrations were similar in both groups. After glucose ingestion, obese individuals had a lower red blood cell total glutathione concentration and increased plasma oxidized glutathione concentration than their lean counterparts (p < 0.05). In addition, obese participants had a higher level of IR (p < 0.001) and impaired serum free-fatty acid suppression (p < 0.001) than their lean counterparts. Ingestion of vanillin did not modify any of these variables when compared with placebo in obese individuals. In lean volunteers a reduction in Matsuda index was detected when vanillin was administered, compared to placebo (4.3 +/- 0.6 and 3.6 +/- 0.6 respectively; p < 0.05). Conclusions: IR was ameliorated after vanillin ingestion among lean but not obese participants.

Coriandrum sativum L. aqueous extract mitigates high fat diet induced insulin resistance by controlling visceral adiposity in C57BL/6J Mice / Coriandrum sativum L. extracto acuoso mitiga dieta rica en grasas de alta resistencia a la insulina inducida por el control de la adiposidad visceral en ratones C57BL/6J

This study investigates the effect of dietary supplementation with Coriandrum sativum L. seed aqueous extract (CS) to a high fat diet (HFD), for induced insulin resistance (IR) C57BL/6J mice. Changes in body weight, food intake, feed efficiency ratio, fasting blood glucose (FBG), plasma insulin, fasting insulin resistance index (FIRI), plasma and hepatic triglyceride (TG), total cholesterol (TC) and, plasma free fatty acid (FFA) levels were evaluated in control and treated groups. Also, the diameter, surface area and number of adipocytes and, intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin response test (IPRTT) were performed. CS supplementation (1 percent and 3 percent w/w) to HFD fed mice (for 12 weeks) significantly prevented HFD induced increment in body weight gain, food intake, feed efficiency, FBG, plasma insulin, FIRI, plasma and hepatic TG and TC and, plasma FFA, adipocyte diameter and surface area along with decrement in adipocyte number. Also, improved responses were recorded in the IPGTT and IPRTT in CS supplemented HFD fed mice. These set of changes were comparable to the rosiglitazone (0.05 percent) supplemented HFD fed mice. Our findings suggest that CS improves insulin sensitivity primarily by mitigating plasma and tissue lipids and, adipocyte hypertrophy.

En este estudio se investigó el efecto de un extracto acuoso de semillas de Coriandrum sativum L. (CS), adicionado a una dieta con alto contenido graso en ratones C57BL/6J, con resistencia a la insulina inducida. Los cambios en el aumento de peso corporal, consumo de alimento, eficiencia alimenticia, glicemia, insulina plasmática, índice de resistencia a la insulina, triglicéridos hepáticos y plasmáticos, colesterol total y concentración plasmática de ácidos grasos libres, fueron evaluados en grupos control y tratados. Adicionalmente se controló, el diámetro, superficie y número de adipocitos, prueba de tolerancia a la glucosa intraperitoneal y la prueba de respuesta de la insulina por vía intraperitoneal. La adición de CS (1 por ciento y 3 por ciento w / w) a la dieta con alto contenido graso a ratones (12 semanas) previno de manera significativa el incremento de peso, la ingesta de alimentos, la eficiencia alimenticia, FBG, la insulina plasmática, FIRI, los triglicéridos hepáticos y plasmáticos, el colesterol total, ácidos grasos libres plasmáticos, el diámetro de los adipocitos y la superficie junto con el decremento en el número de los adipocitos. Además, mejoras de la respuesta se registraron en el IPGTT y IPRTT. Este conjunto de cambios fue comparable al obtenido con rosiglitazona (0,05 por ciento), adicionada a la dieta con alto contenido graso. Estos hallazgos sugieren que el CS mejora la sensibilidad a la insulina principalmente por la mitigación de los lípidos del plasma, del tejido y la hipertrofia del adipocito.

Energy metabolism and fasting in male and female insectivorous bats Molossus molossus (Chiroptera: Molossidae) / Metabolismo energético e resposta ao jejum em morcegos insetívoros Molossus molossus (Chirpotera: Molossidae)

Metabolic adaptations induced by 24 and 48 hours of fasting were investigated in male and female insectivorous bats (Molossus molossus Pallas, 1766). For this purpose, plasma glucose, non esterified fatty acids (NEFA), glycogen, protein and lipids concentrations in liver and muscles were obtained. Data presented here demonstrate that fed bats showed plasma glucose levels similar to those reported for other mammal species. In response to fasting, glycemia was decreased only in 48 hours fasted females. Plasma NEFA levels were similar in both sexes, and did not exhibit any changes during fasting. Considering the data from energy reserve variations, fed females presented an increased content of liver glycogen as well as higher breast muscle protein and limbs lipids concentrations, compared to fed males. In response to fasting, liver and muscle glycogen levels remained unchanged. Considering protein and lipid reserves, only females showed decreased values following fasting, as seen in breast, limbs and carcass lipids and breast muscle protein reserves, but still fail to keep glucose homeostasis after 48 hours without food. Taken together, our data suggest that the energy metabolism of insectivorous bats may vary according to sexual differences, a pattern that might be associated to different reproduction investments and costs between genders.

As adaptações metabólicas induzidas pelo jejum foram investigadas em morcegos insetívoros machos e fêmeas (Molossus molossus Pallas, 1766) alimentados e submetidos ao jejum por 24 e 48 horas. Para este propósito, análises plasmáticas de glucose, ácidos graxos livres, glicogênio, proteína e lipídios do fígado e músculos foram analisados. Os dados obtidos demonstraram que o nível de glicose plasmática em morcegos alimentados foi similar ao apresentado por outras espécies de mamíferos. No entanto, em resposta ao jejum, a glicemia de fêmeas diminuiu significativamente após 48 horas, enquanto os níveis circulantes de machos permaneceram constantes. Os níveis de ácidos graxos não esterificados no plasma foram similares em ambos os sexos, e não houve mudança durante o jejum. Em relação às reservas energéticas, fêmeas alimentadas apresentaram maior teor de glicogênio no fígado, de proteína armazenada no músculo peitoral e lipídios nos músculos dos membros anteriores e posteriores, em comparação aos machos alimentados. Em resposta ao jejum, somente as fêmeas mostraram diminuição de algumas reservas energéticas, como a reserva lipídica dos músculos dos membros anteriores e posteriores, da carcaça e da reserva proteica do músculo peitoral. Apesar desta mobilização, as fêmeas, diferentemente dos machos, demonstraram uma incapacidade de manter a homeostase da glicose após 48 horas sem o alimento. Nossos dados sugerem que o metabolismo energético de morcegos insetívoros varia de acordo com o sexo, sendo que o padrão metabólico pode estar associado a diferenças de custo energético no investimento reprodutivo entre machos e fêmeas.

Association of free fatty acids with the insulin-resistant state but not with central obesity in individuals from Venezuela

Individuals with insulin resistance (IR) usually have upper body obesity phenotype, often accompanied by an increase in plasma free fatty acids (FFA). Since the Venezuelan population has a high frequency of IR and central obesity, the purpose of this work was to determine FFA levels in 47 Venezuelan individuals, men and women, 24-58 years old, and analyze their relationship with central obesity and parameters of carbohydrate and lipid metabolism. Basal concentrations of TG, total cholesterol, LDL-C, and HDL-C were measured, and FFA, glucose and insulin, at basal state and at different times after a glucose load. Eighteen individuals presented insulin resistance (HOMA-IR >2.7) and 29 were non-insulin resistant (non-IR). Insulin resistant individuals (IR) had higher waist circumference, BMI and basal concentrations of FFA than the non-IR. No differences were observed in skin folds and other basal lipids studied. The increased FFA seemed to be related to the IR associated to BMI and not to central obesity, since the difference between IR and non-IR disappeared when they were matched for waist circumference. After a glucose load, FFA decreased in both groups, but remained significantly elevated in IR subjects. This effect disappeared after matching for BMI or waist circumference, inferring that it was independent of anthropometrics. FFA were positively associated with HOMA-IR, glucose and TG levels; however, there was no association with BMI or waist circumference. These findings, and the lack of elements to support the presence of hepatic IR, common to increased visceral lipolysis, might suggest that the IR present in the obese individuals studied, might be due to an increase in subcutaneous fat.

Los individuos con insulino-resistencia (IR) usualmente presentan obesidad central, fenotipo comúnmente acompañado de incremento de ácidos grasos libres (AGL). Como los individuos venezolanos presentan una alta frecuencia de IR y obesidad central, el objetivo de este trabajo fue analizar, en un grupo de ellos, la relación entre AGL y obesidad central y parámetros relacionados con el metabolismo de carbohidratos y lípidos. En 47 venezolanos, hombres y mujeres, entre 24 y 58 años, se determinaron las concentraciones basales de TG, Colesterol total, LDL-C, HDL-C y AGL, glucemia e insulina a nivel basal y a diferentes tiempos después de una sobrecarga glucosada. Dieciocho individuos resultaron IR (HOMA-IR > 2,7) y 29 no IR. Los IR presentaron mayor circunferencia de cintura (CC), índice de masa corporal (IMC) y concentraciones basales de AGL. No hubo diferencias en los pliegues cutáneos ni en los otros lípidos. Los valores elevados de AGL parecieron relacionarse con la IR asociada al IMC y no a la obesidad central puesto que una vez apareados por CC, la diferencia en los valores de AGL entre IR y no-IR desapareció. Después de la sobrecarga glucosada los AGL disminuyeron en ambos grupos, pero permanecieron significativamente elevados en los IR. Esta diferencia desapareció al aparear por IMC o CC. Los AGL estuvieron significativamente asociados a HOMA-IR, glucemia y TG, sin embargo no se encontró asociación con IMC o CC. Estos hallazgos, más la falta de elementos que apoyen la presencia de IR hepática, común en un incremento de la lipólisis visceral, sugieren que la IR presente en estos individuos obesos pueda ser debida a incremento de la grasa subcutánea.

Efeito do exercício físico na sensibilidade à insulina em mulheres obesas submetidas a programa de perda de peso: um ensaio clínico / Effects of exercise on insulin sensitivity in obese women submitted to a weight loss program: a clinical trial

O objetivo deste estudo foi de avaliar o efeito do exercício sobre a sensibilidade insulínica, metabolismo lipídico e perda de peso em mulheres submetidas a programa de redução ponderal. Realizou-se ensaio clínico com 40 mulheres obesas (IMC de 30,41 a 53,29 kg/m²), incluindo 20 em cada grupo. Ambos os grupos (intervenção e controle) receberam orientação nutricional e apoio psicológico. O grupo de intervenção também realizou três sessões semanais de exercícios físicos durante 20 semanas. As variáveis antropométricas foram medidas em três momentos. A análise através de medidas repetidas (modelo linear misto) mostrou redução de 2 kg peso corporal (p = 0,02) e de 0,88 kg/m² no índice de Massa Corporal (p = 0,02), ao final de 20 semanas, do grupo intervenção comparado ao controle. Não foram encontradas diferenças significativas entre os grupos para variáveis relativas à localização da gordura corporal (circunferência de cintura e relação cintura-quadril), perfil lipídico e sensibilidade insulínica medida pelo HOMA-IR. Os ácidos graxos livres apresentaram elevação no grupo intervenção comparado ao controle (diferença entre os grupos = 0,30 mmol/L; p = 0,002). A inclusão de exercícios no programa de redução do peso promoveu maior redução ponderal, aumentou os AGLs, mas não alterou a sensibilidade insulínica em mulheres obesas.

The aim of this study was to evaluate the effects of exercise on insulin sensitivity, lipid metabolism and weight loss in women submitted to a weight reduction program. The study consisted in a clinical trial including 40 obese women (BMI 30.41 to 53.29 kg/m²), 20 in each group. Both groups received nutritional counseling and psychological support. The intervention group participated in supervised exercise three times per week for 20 weeks. For the anthropometric measurements, which were taken at three times, the linear mixed modeling procedure showed a reduction of 2 kg in body mass (p = 0.02) and 0.88 kg/m² in the Body Mass Index (p = 0.02) in intervention group compared with controls after 20 weeks of treatment. We did not detect significant differences between the two groups for body fat location (waist circumference and waist-to-hip ratio), serum lipoprotein profile, and insulin sensitivity evaluated by HOMA-IR. Serum levels of free fatty acids significantly increased in the intervention group compared with controls (difference between groups = 0,30 mmol/L; p = 0,002). The addition of physical exercise in a weight reduction program promoted greater weight loss, increased free fatty acids, but did not alter insulin sensitivity in obese women.

Lipids shed into the culture medium by trypomastigotes of Trypanosoma cruzi

Trypomastigote forms of Trypanosoma cruzi were metabolically labeled with [14C]-ethanolamine and [3H]-palmitic acid. Lipids shed to the culture medium were analyzed and compared with the parasite components. Phosphatidylcholine and lysophosphatidylcholine accounted for 53 per cent of the total incorporated precursor. Interestingly, phosphatidylethanolamine and its lyso derivative lysophosphatidylethanolamine, although present in significant amounts in the parasites, could not be detected in the shed material. Shed lipids were highly enriched in the desaturated fatty acids C16:1 and C18:1 when compared to the total fatty acid pool isolated from the parasites.

Peripheral glucose metabolism in patients with chronic renal failure

The present study was designed to determine the effect of chronic renal failure on forearm muscle glucose uptake and oxidation during the postabsorptive state and after an oral glucose challenge. Twelve normal subjects and sixteen patients with chronic renal failure were studied after an overnight fast (12-14h) and for 3h after the ingestion of 75g glucose. Peripheral glucose metabolism was analyzed by the forearm technique to estimate muscle exchange of substrate combined with indirect calorimetry. decreased forearm glucose uptake was observed in uremic patients compared to normal subjects (9l.5 ñ 11,4 vs 154.8 ñ 7.8mg 100 ml forearm -1 3h-1) with diminished nonoxidative glucose metabolism (69.4 ñ 12.1 vs 117.2 ñ 12.8mg 100 ml forearm-1 3h-1). Muscle glucose oxidation did not difer significantly between groups. Both serum free fatty acid levels and lipid oxidation rates were similar in the normal subjects and the uremic patients, and declined in a similar fashion after glucose ingestion. Basal serum insulin levels did not differ significantly between normal and uremic patients, whereas the insulinemic response to glucose load was greater among the patients with chronic renal failure. These data show that resistance occurring in patients with chronic renal failure is accompanied by impaired muscle glucose uptake and nonoxidative glucose metabolism

Effect of caffeine on the metabolism of rats exercising by swimming

Several studies have demonstrated that caffeine improves endurance exercise performance but the mechanisms are not fully understood. Possibilities include increased free fatty acid (FFA) oxidation with consequent sparing of muscle glycogen as well as enhancement of neuromuscular function during exercise. The present study was designed to investigate the effects of caffeine on liver and muscle glycogen of 3-month old, male Wistar rats (250-300 g) exercising by swimming. Caffeine (5 mg/kg) dissolved in saline (CAF) or 0.9 percent sodium chloride (SAL) was administered by oral intubation (1 µl/g) to fed rats 60 min before exercise. The rats (N = 8-10 per group) swam bearing a load corresponding to 5 percent body weight for 30 or 60 min. FFA levels were significantly elevated to 0.475 + or - 0.10 mEq/l in CAF compared to 0.369 + or - 0.06 mEq/l in SAL rats at the beginning of exercise. During exercse, a significant difference in FFA levels between CAF and SAL rats was observed at 30 min (0.325 + or - 0.06 vs 0.274 + or - 0.05 mEq/l) but not at 60 min (0.424 + or - 0.13 vs 0.385 + or - 0.10 mEq/l). Blood glucose showed an increase due to caffeine only at the end of exercise (CAF = 142.1 + or - 27.4 and SAL = 120.2 + or - 12.9 mg/100 ml). No significant difference in liver or muscle glycogen was observed in CAF as compared to SAL rats, at rest or during exercise. Caffeine increased blood lactate only at the beginning of exercise (CAF = 2.13 + or - 0.2 and SAL = 1.78 + or - 0.2 mmol/l). These data indicate that caffeine (5 mg/kg) has no glycogen-sparing effect on rats exercising by swimming even though the FFA levels of CAF rats were significantly higher at the beginning of exercise

Alterations of lipid kinetics and lipoprotein lipase activity in jaundiced tumor bearing rats

Obstructive jaundice is associated with high perioperative morbidity and mortality, and preoperative biliary decompression is still controversial. Profound alterations in intermediary metabolism have been observed with obstructive jaundice. To determine the effect of the common bile duct (CBD) obstruction on lipid metabolism in tumor-bearing animals, free fatty acid (FFA) and very low density lipoprotein-associated triglyceride (VLDL-TG) kinetics were assessed in 20 tumor bearing (subcutaneous MCA sarcoma) Fischer-344 rats, using an obstructive jaundice model. The animals were studied after chronic vascular catheterization, in an unanesthetized, undisturbed state. They were separated into 4 groups: Normal controls (CTL), Tumor-bearing non-jaundiced rats (TBR), Non Tumor Bearing-Jaundiced (NTB-J), Tumor Bearing (tumor burden: 1O per cent body weight)-Jaundiced (TBR-J). All rats were studied 7 days after CBD ligation, or at 1O per cent tumor burden. VLDL-TG and FFA kinetics were assessed by constant infusion of 3H-palmitate-labeled VLDL-TG, and l4C-palmitate bound to albumin, respectively. FFA rate of appearance (FFA-Ra) and clearance (FFA-CI), VLDL-TG rate of appearance (VLDL-TG-Ra) and clearance (VLDL-TG-CI) were determined at steady-states. Tumor burden signiricantly affects FFA-Ra and FFA-CI, as well as VLDL-TG-CI, while CBD ligation selectively affects VLDL-TG-Ra and VLDL-TG-CI. There was significant interaction between tumor burden and jaundice in FFA-Ra. CBD decompression increased significantly VLDL-TG-CI. We conclude that, in jaundiced tumor-bearing rats, tumor burden predominantly affects lipolysis, while CBD obstruction primarily affects triglyceride synthesis and clearance. Lipoprotein lipase (LPL) activity was also markedly decreased by the presence of jaundice and tumor burden, with the associated decrease in the clearance of VLDL-TG.

Comparaçäo entre medicamentos orais através das taxas séricas de glicose, amilase, ácidos graxos livres e lipoproteínas de alta densidade (HDL-Colesterol) nos diabéticos de ambos os sexos, da regiäo de Araraquara, näo-dependentes de insulina / Comparison of oral medicaments through serum levels of glucose, amilase, free-fatty acids and high density cholesterol (HDL-Colesterol) in non-insulin-dependent diabetics patiens from both sex in the region of Araraquara

Neste estudo foram comparados os efeitos terapêuticos de glibenclamida (DAONIL) e clorpropamida (DIABINESE) em pacientes de ambos os sexos com diabetes do tipo II sobre os parâmetros séricos: glicose, amilase, HDL-colesterol e ácidos graxos livres. Os resultados indicam que as duas drogas foram potencialmente semelhantes sobre a glicemia, HDL-colesterol e AGL em ambos os grupos, masculino e feminino. A droga clorpropamida foi significativamente mais efetiva em reduzir a atividade da amilase no grupo diabético masculino que a glibenclamida. As citadas drogas hipoglicemiantes näo reduziram a níveis basais nos grupos diabéticos masculino e feminino

Studies on nonesterified fatty acids in rat intestinal cell membranes.

Lipid composition of total membrane fractions prepared from scraped rat intestinal mucosa and isolated epithelial cells were compared. Membranes prepared from mucosa had four times higher nonesterified fatty acids (NEFA) as compared to the epithelial cell membranes. Cholesterol and phospholipid contents were similar in both the membrane preparations but triglyceride content was high and di- and monoglyceride were low in epithelial cell membranes as compared to the mucosal membranes. Inclusion of p-bromophenacyl bromide, a phospholipase inhibitor, in the intestinal lumen wash solution and homogenizing buffer did not reduce the NEFA content of the scraped mucosal membranes whereas inclusion of diethyl p-nitrophenyl phosphate, a lipase inhibitor reduced it by 40%. These results suggest that NEFA are normal constituent of intestinal cell membranes.