A study on the short-term effect of cafeteria diet and pioglitazone on insulin resistance and serum levels of adiponectin and ghrelin

The interaction between ghrelin and adiponectin is still controversial. We investigated the effect of cafeteria diet and pioglitazone on body weight, insulin resistance, and adiponectin/ghrelin levels in an experimental study on male Wistar rats. The animals were divided into four groups of 6 rats each, and received balanced chow with saline (CHOW-O) or pioglitazone (CHOW-P), or a cafeteria diet with saline (CAFE-O) or pioglitazone (CAFE-P). The chow/cafeteria diets were administered for 35 days, and saline/pioglitazone (10 mg·kg body weight-1·day-1) was added in the last 14 days prior to euthanasia. CAFE-O animals had a higher mean final weight (372.5 ± 21.01 g) than CHOW-O (317.66 ± 25.11 g, P = 0.017) and CHOW-P (322.66 ± 28.42 g, P = 0.035) animals. Serum adiponectin levels were significantly higher in CHOW-P (55.91 ± 20.62 ng/mL) than in CHOW-O (30.52 ± 6.97 ng/mL, P = 0.014) and CAFE-O (32.54 ± 9.03 ng/mL, P = 0.027) but not in CAFE-P. Higher total serum ghrelin levels were observed in CAFE-P compared to CHOW-P animals (1.65 ± 0.69 vs 0.65 ± 0.36 ng/mL, P = 0.006). Likewise, acylated ghrelin levels were higher in CAFE-P (471.52 ± 195.09 pg/mL) than in CHOW-P (193.01 ± 87.61 pg/mL, P = 0.009) and CAFE-O (259.44 ± 86.36 pg/mL, P = 0.047) animals. In conclusion, a cafeteria diet can lead to a significant weight gain. Although CAFE-P animals exhibited higher ghrelin levels, this was probably related to food deprivation rather than to a direct pharmacological effect, possibly attenuating the increase in adiponectin levels.

Differential Effects of High-carbohydrate and High-fat Diet Composition on Muscle Insulin Resistance in Rats

This study was conducted to evaluate whether the composition of carbohydrate or fat diet affects insulin resistance by measuring the muscle glucose transport rate. Both high-sucrose and high-starch diet with or without high-fat decreased insulin-stimulated glucose transport, but there were no significant differences among groups. Calorie intake in both high-sucrose and high-starch diet groups was higher than in chow group. The high-fat high-sucrose diet induced decrease in insulin-stimulated glucose transport was partially improved by supplement with fish oil. Calorie intake in high-fat high-sucrose and fish oil supplemented groups was higher than in chow group. The decreased insulin-stimulated glucose transport was accompanied by the increase in visceral fat mass, plasma triglyceride and insulin levels. These changes were improved by the supplement with fish oil. These results demonstrate that the composition of fat in diet is clearly instrumental in the induction of muscle insulin resistance. However, in high carbohydrate diet, it is likely that the amount of calorie intake may be a more important factor in causing insulin resistance than the composition of carbohydrate. Thus, the compositions of carbohydrate and fat in diet differentially affect on muscle insulin resistance.

Effects of high-carbohydrate and high fat diet on formation of foam cells and expression of TNF-alpha in Rattus novergicus.

AIM: to examine the role of high carbohydrate and high fat diet on formation of foam cells and expression of TNFalpha, an early stage of atherosclerosis. METHOD: three months old male Rattus Novergicus strain Wistar were allocated into 3 groups, normal diet group (GI, n=8), high carbohydrate diet group (GII, n=8), and high fat diet group (G III, n=8). Those groups received an isoenergetic diet but contained different percentage of carbohydrate and fat for 12 weeks. The rest of the food was measured daily to calculate the calorie intake. The body weight was measured weekly. At the end of study, blood samples were taken using cardiac puncture to examine lipid profiles and random blood sugars. RESULTS: levels of blood glucose significantly increased in GII compared to the GI (281.87 +/- 39.66 mg/dl vs 192.5 +/- 1.4 mg/dl, p=0.002). Group II and G III showed increased of triglyseride compared to GI (138.0 +/- 47.15 vs 85.5 +/-20.3, p=0.02; 163.62 +/- 41.77 vs 85.5 +/- 20.3, p=0.00, respectively). Level of LDL significantly increased in G III compared to GI (72 +/- 35.6 vs 27.0 +/- 8.9, p=0.00). No statistical difference in level of HDL among the three groups. Level of TNFalpha significantly increased in GII and G III compared to GI (19.13 +/- 3.68 vs 2.5 +/- 1.4, p=0.00; 23.6 +/- 5.58 vs 2.5 +/- 1.4, p=0.00, respectively). The number of foam cells was significantly increased in GII and G III compared to GI (7.18 +/- 5.28 vs 1.2 +/- 1.4, p=0.00; 9.91 +/- 6.26 vs 1.2 +/- 1.4, p=0.00, respectively). The foam cell had strong correlation with triglyseride level and TNFalpha (r=0.696, p=0.00; r=0.618, p=0.00, respectively). CONCLUSION: this result shows that high carbohydrate and high fat diet potentially increase the risk factor of atherosclerosis. Both diets induced the inflammatory process and increase foam cells formation, are in the early stage of atherosclerosis.

Effect of an alcoholic diet on dental caries and on Streptococcus of the mutans group: study in rats

The objective of this study was to evaluate the effects of an alcohol diet on Streptococcus of the mutans group and on dental caries in the oral cavity of rats. Forty animals were divided into 3 groups according to the following liquid diets: 20 percent ethanol solution (Alcohol Group, AG), 27 percent sucrose solution (Isocaloric Group, IG), and water (Control Group, CG). After 56 days, samples were collected and plated on Mitis Salivarius Bacitracin agar to assess the number of colony forming units (CFU/mL) of Streptococcus of the mutans group. The animals were sacrificed and the jaws were removed in order to assess the occurrence of dental caries on the smooth and occlusal surfaces using stereomicroscopy. The data were submitted to ANOVA and Tukey test. The average numbers of CFU/mL (10³) were: 8.17 (AG), 9.78 (IG), and 5.63 (CG). There was no significant difference among the groups for the occurrence of occlusal caries. Regarding smooth surface caries, in the upper jaw, the caries number in the IG (1.58) was similar to that in the AG (2.06) and in the CG (1.14), and the number of caries in the AG was higher than in the CG; in the lower jaw there was significant difference among the 3 groups: AG (1.14), IG (2.00) and CG (0.43). The diets with the alcohol and sucrose solutions presented a tendency of increasing the colonization by Streptococcus of the mutans group and of increasing the occurrence of smooth surface dental caries in rat molars when compared to the control diet.

O presente estudo avaliou o efeito de uma dieta alcoólica sobre estreptococos do grupo mutans e sobre cárie dentária na cavidade bucal de ratos. Quarenta animais foram divididos em 3 grupos conforme a dieta líquida administrada: solução de etanol a 20 por cento (Grupo álcool, GA), solução de sacarose a 27 por cento (Grupo isocalórico, GI) e água (Grupo controle, GC). Após 56 dias, amostras bucais foram coletadas e semeadas em ágar Mitis Salivarius Bacitracina para contagem de unidades formadoras de colônias (UFC/mL) de estreptococos do grupo mutans. Os animais foram sacrificados, maxila e mandíbula foram removidas para analisar a ocorrência de cárie nas faces livres e oclusais usando lupa estereoscópica. Os dados foram submetidos à ANOVA e ao teste de Tukey. As médias dos números de UFC/mL (10³) foram: 8,17 (GA), 9,78 (GI), e 5,63 (GC). Não houve diferença significativa entre os grupos para a ocorrência de cárie oclusal. Em relação ao número de cáries em face livre, na maxila este número no GI (1,58) foi similar ao encontrado no GA (2,06) e no GC (1,14), e o número de cáries no GA foi maior do que no GC; na mandíbula houve diferença significante entre os três grupos: GA (1,14), GI (2,00) e GC (0,43). A dieta com soluções de álcool e sacarose apresentou tendência de aumento na colonização de estreptococos do grupo mutans e aumentou a incidência de lesões de cárie de faces livres nos molares de ratos quando comparada à dieta controle.

Acidogenic potential of Soya infant formula in comparison with regular infant formula and bovine milk: a plaque pH study.

Soya infant formulas are essential for infants intolerant to cow's milk. Soya formulas contains glucose syrup or maltodextrins instead of Lactose, which has led to concern that they are potentially more cariogenic than standard infant formulas containing lactose. The study was conducted to compare the acidogenic effect of Soya Infant formula, infant formula and bovine milk. The study group consisted of 75 children in the age group of 7-10 years. The plaque pH was measured using plaque pH meter, before and after rinsing with different samples for sixty minutes Soya infant formula is found to be more acidogenic than infant formula (with lactose) and bovine milk. This study demonstrates high caries inducing potential of Soya infant formula. Further awareness of the possible role of Soya infant formula in early childhood caries is required.

Consumo de alimentos cariogénicos y caries en escolares con dentición temporal y permanente / Cariogenic food consumption and dental caries in school children with temporary and deciduos dentition

Con el propósito de relacionar el consumo de alimentos cariogénicos y daño dentario, se estudió a escolares de 1º y de 8º año de enseñanza básica, de 6 y 13 años de edad respectivamente, pertenecientes a establecimientos educacionales de un sector de extrema pobreza de Santiago. Para determinar el consumo de alimentos cariogénicos se confeccionó una encuesta alimentaria que consignó los alimentos ricos en hidratos de carbono. Se le asignó un nivel de cariogenicidad a la dieta, según el tipo y frecuencia de consumo de los alimentos que la constituían. El daño dentario se determinó a través del índice de piezas cariadas, obturadas y perdidas, coed para dentinción temporal y COPD para dentición permanente. Al correlacionar consumo de dieta cariogénica e índice coed-COPD no se encontró una relación estadísticamente significativa entre ellas, a pesar de que la mayoría de los escolares consumían una dieta de mediana cariogenicidad y presentaban un alto porcentaje de daño dentario. Este resultado se atribuyó a que la encuesta alimentaria no estaría reflejando el real consumo de alimentos cariogénicos y por lo tanto no tendría validez como elemento predictor de caries por sí sola

Effect of macrocomponents of food on the pharmacokinetics of a long acting preparation of anhydrous theophylline.

In a single dose crossover study, the effect of macrocomponents of food on the pharmacokinetics of a long acting preparation of anhydrous theophylline was investigated. Compared to fasting subjects, carbohydrate and fat rich diet caused an enhancement of absorption half life and a lower Cmax with a delayed tmax and elimination of the bronchodilator. Protein coadministration decreased AUCO-OC of the drug without significantly altering its absorption or elimination kinetics.

Glycaemic response to maize, bajra and barley.

The postprandial glycaemic response to maize (Zea mays), bajra (Pennisetum typhoideum) and barley (Hordeum vulgare) was studied in a pool of 18 healthy volunteers and 14 patients having non-insulin-dependent diabetes mellitus (NIDDM). In response to maize, none of the variables examined was significantly different as compared to white bread. The glycaemic response to bajra was significantly lower than that to white bread in healthy subjects, but the two responses were indistinguishable in NIDDM subjects. The insulinaemic responses to bajra and white break were not significantly different in either group of subjects. The glycaemic response to barley was significantly lower than that to white bread in both groups of subjects. But the insulinaemic response to barley was significantly lower than that to white bread only in healthy subjects. In NIDDM subjects, there was a tendency for the response to barley to be higher than that to white bread 0.5 h after ingestion. Barley, with a low glycaemic index (68.7 in healthy and 53.4 in NIDDM subjects) and a high insulinaemic index (105.2) in NIDDM subjects seems to mobilize insulin in NIDDM. This makes it a specially suitable cereal for diabetes mellitus.

Involvement of dietary glucose in adrenal steroidal regulation of spermatogenic and steroidogenic activities in prepubertal rat testis.

Effects of dietary and supplemented dextrose energy on the role of corticosterone (Comp. B) or dehydroepiandrosterone (DHA) in spermatogenic and steroidogenic activity in the bilaterally adrenalectomised prepubertal rat testis were studied. Adrenalectomy reduced the body and testis weight, numbers of the stage VII cell types [spermatogonia A (A), preleptotene (PL) and pachytene (P) spermatocytes and step 7 spermatid (7)], testicular delta 5-3 beta-hydroxysteroid dehydrogenase (delta 5-3 beta-OH-SDH) activity and serum testosterone. Adrenalectomy also caused reduction of energy intake due to loss of appetite which was stimulated by hormone replacement therapy. Treatment of adrenalectomised rats with DNA or corticosterone enhanced the spermatocyte population and the enzyme activity, especially after 30 days of age. Dextrose supplementation with hormone treatment however, did not produce significant additive effect on stage VII cell counts, but delta 5-3 beta-OH-SDH activity showed additive effect in this age group. Results suggest that adrenal steroids regulate testicular steroidogenesis and spermatogenesis during the prepubertal ages by modifying the supply of dietary glucose.

Nutrient interaction in relation to glycaemic response in isocarbohydrate and isocaloric meals.

The present study was designed to examine the effect of casein (Cs) on postprandial glycaemia when ingested with glucose (G) alone or in combination with corn oil (Co), cellulose (Cl) or pectin (P). The study was conducted on a pool of ten healthy male volunteers in two sets of five volunteers each. The meals administered in the two sets were similar in composition but were isocarbohydrate (100 g G) in one set, and isocaloric (400 kcal) in another set. The meals in each set consisted of G, G Cs, G Cs Co, G Cs Cl and G Cs P. Each of the five volunteers in a given set underwent five meal tolerance tests (MTT), once with each meal, in a Latin Square design. During the MTT, the meal was administered after an overnight fast. In addition to a fasting venous blood sample, blood was collected 0.5, 1.0, 1.5 and 2.0 h after ingestion for measurement of serum glucose and insulin levels. In both sets, the highest glycaemic response was that to G. In the isocarbohydrate set, G Cs gave a significantly lower glycaemic and insulinaemic response than G. Further addition of Co made no essential difference but both the fibre containing meals gave significantly lower glycaemic responses. The insulinaemic response was attenuated only in case of G Cs P but not in case of G Cs Cl. In the isocaloric set, Cs as G Cs was observed to stimulate insulin secretion rather than attenuate postprandial glycaemia G Cs Co gave a reduction in glycaemic as well as insulinaemic response as compared to G. Both fibre containing meals led to further reduction in both responses, P being somewhat more effective than Cl. Addition of other nutrients to G, in general, reduces postprandial glycaemia.

REM sleep deprivation and food intake.

The effect of REM-sleep deprivation (REM-SD) on diet preference was studied in rats. REM-SD for a period of 72 hrs produced an increase in day, night and 24 hrs (day plus night) intakes of Carbohydrate Rich diet (CRD) and Total diet (TD). Body weight (BWt) was also increased. The maximum increase in the above parameters were recorded on the 2nd day of REM-SD. During recovery period the intakes of TD fully recovered, but the BWt and consumption of CRD remained high. Intakes of Balanced diet (BD) remained significantly on the lower side when compared to the pre REM-SD mean values. During REM-SD, the rats preferred CRD than BD. The body temperature did not show any change. The increase in TD intake and BWt could be the result of an increase in insulin level and the change appears to be mediated by the activation of hypothalamic feeding centre.

Effect of high carbohydrate and high protein diets on microsomal fatty acid composition, fluidity and delta 6 desaturation activity in kidney and lung

La administración dietas hiperglucídicas e hiperproteicas suministradas a ratas durante 3 días produce respectivamente una disminución y un aumento en el cociente araquidonato/linoleato en los lípidos totales de microsomas de pulmón, riñon e hígado. En el hígado y el riñon este efecto está correlacionado con un significativo descenso de la actividad de la delta6 desaturasa para el caso de la dieta hiperflucídica y con un aumento de la misma actividad enzimática en la dieta hiperproteica. La actividad de la delta6 desaturasa, medida a través de la conversión del ácido 1-14**C linoleico a ácido alfa-linolénico, no se detectó en los microsomas de pulmón debido probablemente a la poca capacidad de este tejido para producir el éster de CoA del sustrato usado, y a que el cociente 20:4/18:2 en este tejido fue similar al del hígado bajo las condiciones dietéticas analizadas. La anisotropía de fluorescencia (r) del definilhexatrieno mostró diferencias significativas entre los tres tejidos analizados, efecto que se correlacionó con sus respectivos cocientes colesterol/fosfolípidos. Ambos parámetros fueron inferiores en los microsomas hepáticos que en los de los otros tejidos y permanecieron sin modificarse bajo los diferentes regímenes estudiados. Los resultados indican que el efecto de las dietas hiperhidrocarbonada e hiperproteica sobre la delta6 desaturasa no conduce a alteraciones aparentes en las propiedades físicas de las membranas microsomales

Effects of some carbohydrates on iron absorption

Se llevaron a cabo dos experimentos, con el propósito de examinar el efecto de varios carbohidratos (fructosa, lactosa, almidón de maíz, almidón de papa y almidón de trigo) en la utilización del hierro, por ratas deficientes en este elemento. Las ratas recibieron una sola comida marcada con 59Fe que contenia el carbohidrato a ensayar a un nivel de 60%. En el resto del experimento las ratas fueron alimentadas ad libitum con una dieta que contenía glucosa como fuente de carbohidratos al nivel de 60%. En ambos ensayos las ratas no recibieron alimento durante la noche anterior, y la dosis se ofreción como una comida, en la mañana. Para determinar el hierro 59, las ratas se contaron en un "contador de cuerpo entero entre dos y cuatro horas después de la dosis, y cada día durante los 10 días siguientes. Se determinarón el porcentaje de retención y el porcentaje de absorción así como los valores de hemoglobina. En el primer experimento, el reemplaxo de glucosa por fructosa al nivel de 60% aumentó significativamente la retención y la absorción del hierro. Con la lactosa también se notó un aumento de estos parámetros, pero dicho incremento no fue estadísticamente significativo. La administración de 59Fe como un quelato 59Fe-fructosa no tuvo efecto significativo en la retención y absorción del hierro, comparada con el efecto resultante de dosificar con el 59Fe absorbido a la fructosa. Este hallazgo no descarta la posibilidad de que la quelación sea el mecanismo responsable del efecto promotor de la fructosa en la basroción del hierro. El complejo puede haberse formado en el estómago, dando como resultado una absorción similar para la comida marcada con 59Fe, y la marcada con el complejo 59Fe-fructosa...