Oleic acid acutely impairs glucose homeostasis in standard chow diet but not high-fructose, high-fat diet-fed mice by acting on free fatty acid receptor 1

Abstract This study aimed to investigate the acute effects of oleic acid (OA) on glucose homeostasis in mice fed a standard chow diet (SCD) and a high-fructose, high-fat diet (HFrHFD); moreover, the role of free fatty acid receptor 1 (FFAR1) was evaluated. The mice in the two groups were further divided into three subgroups as follows: control, OA (40 mg/kg), and OA + GW1100 (0.4 mg/kg, selective FFAR1 blocker). After a 16-week feeding period, the mice received the drugs via intraperitoneal (i.p.) injection followed by an i.p. glucose tolerance test (IPGTT) 30 min later. After 3 days, the mice received the same drugs to examine the effects of the drugs on the hepatic levels of phosphatidylinositol-4,5-bisphosphate (PIP2) and diacylglycerol (DAG). OA in the SCD-fed mice significantly increased the blood glucose level (48%, P < 0.001) after 30 min of glucose load compared to that in the control group, but did not affect the levels of PIP2 and DAG. Pre-injection with GW1100 significantly decreased the area under the curve of the IPGTT (28%, P < 0.05) in the SCD group compared to that in the SCD + OA group. OA reduced the blood glucose level (35%, P < 0.001) after 120 min of glucose load in the HFrHFD-fed mice; in addition, it increased hepatic PIP2 (160%, P < 0.01) and decreased hepatic DAG (60%, P < 0.001) levels. Pre-injection with GW1100 blocked the effects of OA on hepatic PIP2 and DAG without affecting the glucose tolerance. In conclusion, OA acutely impaired the glucose tolerance in the SCD-fed mice by acting on FFAR1 but did not improve it in the HFrHFD-fed mice.

Nutritional research and fetal programming: parental nutrition influences the structure and function of the organs / Investigación nutricional y programación fetal: la nutrición parental influye en la estructura y función de los órganos

SUMMARY: Rodents are animals extensively used in biomedical and nutrition research, a necessary step before the research in humans. The composition and type of administration of the experimental diets are relevant and should be thought, considering each type of animal used in the research. It is particularly important to consider, among others, the metabolic differences between species and food needs in macro- and micronutrients to avoid possible bias. The American Institute of Nutrition (AIN) made recommendations for rodents, adapted to the period of growth (AIN-93G), which are pivotal in fetal programming studies. The experiments can be compared among different studies and better translated into humans, considering these limitations in the nutrition of parents and offspring. The review addresses different compositions of experimental food for rodents during development with the ability to induce fetal programming in the offspring and chronic diseases in adulthood due to the nutrition of the mother and father. The 'developmental origins of health and disease' (DOHaD) concept due to maternal nutrition is commented considering the protein restriction, vitamin D restriction, obesity, and intake of fructose or fish-oil. The 'paternal origins of health and disease transmission' (POHaD), because of the nutritional state of the father, were also analyzed in the review, primarily considering the obesity of the father. The review proposes some diet compositions to experimental research considering varied nutritional situations, hoping to assist young researchers or researches not familiar with experimental diet manipulations in the elaboration of the projects.

RESUMEN: Los roedores son animales utilizados frecuentemente en la investigación biomédica y nutricional, un paso necesario antes de la investigación en humanos. La composición y el tipo de administración de las dietas experimentales son relevantes y se debe considerar cada tipo de animal utilizado en los estudios. Es particularmente importante considerar las diferencias metabólicas entre las especies y las necesidades alimentarias de macro y micronutrientes para evitar posibles sesgos. El Instituto Americano de Nutrición (AIN) estableció recomendaciones para los roedores, adaptadas al período de crecimiento (AIN-93G), que son fundamentales en los estudios de programación fetal. Los experimentos se pueden comparar entre diferentes estudios y aplicar en humanos, considerando estas limitaciones en la nutrición de padres e hijos. La revisión aborda diferentes composiciones de alimentos para estudios experimentales en roedores durante su desarrollo, con la capacidad de inducir programación fetal en la descendencia y enfermedades crónicas en la adultez, considerando la nutrición de los padres. El concepto de 'orígenes del desarrollo de la salud y la enfermedad' (DOHaD) debido a la nutrición materna se comenta considerando la restricción de proteínas, la restricción de vitamina D, la obesidad y la ingesta de fructosa o aceite de pescado. Los 'orígenes paternos de la salud y transmisión de enfermedades' (POHaD), debido al estado nutricional del padre, también fueron analizados considerando principalmente la obesidad del padre. La revisión propone algunas composiciones dietéticas a la investigación experimental considerando situaciones nutricionales variadas, con la esperanza de ayudar a jóvenes investigadores o investigadores no familiarizados con las manipulaciones experimentales de la dieta en la elaboración de los proyectos.

Investigation of the effect of coffee on body weight, serum glucose, uric acid and lipid profile levels in male albino Wistar rats feeding on high-fructose diet / 한국실험동물학회지

Coffee is one of the most commonly consumed beverages in the worldwide and is assumed to have protective effects against metabolic syndrome. The present study was aimed at investigating the effect of coffee on body weight, serum glucose, uric acid and lipid profile levels in male albino Wistar rats feeding on high fructose diet. A post-test experimental study was conducted on a total of 30 (9–10 weeks old) male albino Wistar rats. The rats were divided into 6 groups: group I (normal control)-fed on standard chow and plain tap water only; group II (fructose control)-fed on standard chow and 20% of fructose solution; group III–VI (treatment groups)-fed on standard chow, 20% of fructose solution and treated with 71, 142, 213 and 284 mg/kg body weight/day of coffee respectively for six weeks. At the end, body weight, serum glucose, uric acid and lipid profile levels were investigated. Data was entered and cleared by epi-data software version 3.1 and analyzed by one way ANOVA followed by Tukey post hoc multiple comparison tests using SPSS V. 23.00. Statistical significance was considered at p < 0.05. The results showed that body weight, fasting serum glucose and uric acid levels significantly lowered in rats treated with 213 (p = 0.047; 0.049; 0.026) and 284 (p = 0.035; 0.029; 0.010) mg/kg body weight/day of coffee compared to fructose control group. Fasting serum triglycide (TG) and low density lipoprotein (LDL-C) levels showed significant reduction in rats treated with 284 mg/kg body weight/day of coffee as compared to fructose control group (p = 0.031; 0.046) respectively. In conclusion, treating rats with coffee decreased body weight, fasting serum glucose, uric acid, TC, TG and LDL-C, and increased HDL-C in a dose dependent manner in rats feeding on high fructose diet, suggesting that coffee consumption may be helpful in ameliorating metabolic syndrome.

Experimental study of high fat diet plus dexamethasone for inducing acute fatty liver model in mice / 重庆医学

Objective To study the drug dosage and time dependency characteristics of high-fructose-high-fat-feeding plus dexamethason for inducing the mouse acute fatty liver model and to optimize the condition of drug induced fatty liver model.Methods Male KM mice were divided into the normal control group and high-fructose-high-fat-feeding plus peritoneal injection of dexamethason group.The mice were killed at 3 different time points.The mouse body mass and liver mass were detected.The liver index was calculated.The serum and liver tissue homogenate TG and serum glucose(GLU) levels were detected.The liver tissue pathological change was observed by HE staining.Total RNA reverse expression related gene was extracted from the liver tissue.The total protein was extracted from the liver tissue and the related protein expression was detected by Western Blot.Results Compared with the control group,blood and liver homogenate TG after 7 d in the dexamethason model group was increased,the liver index was increased,the pathological section displayed that the fatty liver was formed.RT-PCR showed that lipid metabolism related gene expression had obvious change.Western Blot showed that SIRT1 was significantly decreased.But with the dexamethason dosage decrease and time extending,the fatty liver related indexes were decreased,lipid metabolic gene PPAR,FOXO3 and FXR were gradually increased,while LXR was gradually decreased and protein SIRT1 was gradually increased.Conclusion High-fructose-high-fatfeeding plus peritoneal injection of dexamethason could establish the mouse acute fatty liver model,moreover the model maintenance has dependency on dexamethason dosage and medication time,which has a guidance significance for the drug interventional experiment.

High fructose and high fat diet increased bone volume of trabecular and cortical bone in growing female rats / 한국영양학회지

PURPOSE: The objective of this study was to investigate the effects of a high fructose and fat diet on bone growth and maturation in growing female rats. METHODS: Three-week-old female SD rats were randomly assigned to four experimental groups; the control group (CON: fed control diet based on AIN-93G, n = 8); the high-fructose diet group (HFrc: fed control diet with 30% fructose, n = 8); the high-fat diet group (Hfat: fed control diet with 45 kcal% fat, n = 8); and the high-fat diet plus high fructose group (HFrc + HFat: fed diets 45 kcal% fat with 30% fructose, n = 8). Each group was assigned their respective diets for the remaining eight weeks. Bone-related parameters (bone mineral density (BMD) and structural parameters, osteocalcin (OC), deoxypyridinoline (DPD)) and morphologic changes of kidney were analyzed at the end of the experiment. RESULTS: Final body weights and weight gain were higher in the HFat and HFrc + HFat groups and showed higher tendency in the HFrc group compared with those of the CON group (p < 0.05); however, no significant difference in caloric intake was observed among the four experimental groups. The serum OC levels of the HFrc and HFrc + HFat groups were lower than those of the CON and HFat groups (p < 0.05). Urinary levels of DPD did not differ among the experimental groups. BV/TV and Tb.N of trabecular bone were higher in the HFrc + HFat group and showed a higher tendency in the HFrc group than those of the CON and HFat groups (p < 0.05). Tb.Pf of trabecular bone were lower in the HFrc + HFat group than those in the CON and HFat groups (p < 0.05). However, no difference in trabecular BMD was observed among the experimental groups. Cortical bone volume was higher in the HFat and HFrc + HFat groups than in the CON and HFrc groups (p < 0.05). No morphology change in kidney was observed among the experimental groups. CONCLUSION: Our study suggests that 8 weeks of high-fructose and high fat intake could improve the bone quality (Structural parameters) of trabecular and cortical bone of tibia in growing female rats.

Effect of Polyherbal Formulation on Metabolic Derangements in Experimental Model of High Fructose Diet Induced Metabolic Syndrome.

High fructose diet induces metabolic syndrome. Therefore an attempt has made to evaluate the effect of Polyherbal formulation in male Wistar rats by oral administration of 350 mg/Kg body weight (HF1) and 500 mg/ Kg body weight (HF2). The clinical symptoms established in high fructose diet induced metabolic syndrome were ameliorated by Poly herbal formulation. Food, water intake was increased in high fructose diet fed rats. Body weight, abdominal waist and Body mass index were increased in only high fructose fed rats whereas reduced with poly herbal formulation. Atherogenic index and Blood pressure were increased in only high fructose fed rats but reduced in rats supplied with polyherbal formulation (HF1 and HF2) along high fructose. Biochemical components like fasting blood glucose levels, triglycerides, total cholesterol, LDL, VLDL, SGOT, SGPT, Uric acid, Malondialdehyde (MDA) were increased in only high fructose fed group rats whereas these components were reduced and normalised in groups of rats fed with high fructose diet for 7 weeks in association with Herbal formulation HF1, HF2 for last three weeks separately.HDL-C levels were found increased in rats even though supplied with polyherbal formulation. Histopathology results of pancreas and liverof only high fructose fed rats indicated the infiltration of inflammatory cells and fat accumulation which was ameliorated with HF1 and HF2.

Anti-diabetic effect of a combination of andrographolide-enriched extract of Andrographis paniculata (Burm f.) Nees and asiaticoside-enriched extract of Centella asiatica L. in high fructose-fat fed rats.

Traditionally, a combination of medicinal plants is commonly used for lowering blood glucose in diabetic patients in order to provide additional benefits of the single drug. A. paniculata and C. asiatica are two traditional medicines form South Asian and Southeast Asain countries consumed by people for treating daibates mellitus and its complications. Hyperglycemia in the rats was stimulated by high fructose-fat diet that consists of 36% fructose, 15% lard, and 5% egg yolks in 0.36 g/200 g body weight for 70 days. The rats were orally administered with the combination of andrographolide-enriched extract of A. paniculata (AEEAP) leaves and asiaticoside-enriched extract of C. asiatica (AEECA) herbs from day 70 for 7 days. Antidiabetic activity was evaluated by estimating mainly the blood glucose levels and other parameters such as HDL, LDL, cholesterol and triglyceride. The results showed that combination at the ratio of 70:30 exhibited a promosing antidiabetic effect in high-fat-fructose-fed rat, and exhibited sinergistic effects on blood cholesterol and HDL levels. It can be concluded that its antidiabetic effect was better than that of single treatment of AEEAP or AEECA. That combination was also potential to develop as a blood glucose-lowering agent for diabetic patients.

Glycyrrhizin ameliorates insulin resistance, hyperglycemia, dyslipidemia and oxidative stress in fructose-induced metabolic syndrome-X in rat model.

This study investigates if glycyrrhizin, a constituent of licorice (Glycyrrhiza glabra) root, is able to treat the complications (insulin resistance, hyperglycemia, dyslipidemia and oxidative stress) of metabolic syndrome. Metabolic syndrome was induced in rats by feeding a fructose-enriched (60%) diet for six weeks, after which single dose of glycyrrhizin (50 mg/kg body weight) was administered intraperitoneally. Different biochemical parameters from blood were estimated during three weeks after treatment. Then the rats were sacrificed to collect skeletal muscle tissue. Glycyrrhizin reduced the enhanced levels of blood glucose, insulin and lipids in metabolic syndrome group. Increased advanced glycation end products of hemoglobin, glycohemoglobin, hemoglobin-mediated iron release and iron-mediated free radical reactions (arachidonic acid and deoxyribose degradation) in metabolic syndrome were inhibited by glycyrrhizin treatment. Reduced activities of enzymatic antioxidants (superoxide dismutase and catalase) and elevated oxidative stress markers (malonaldehyde, fructosamine, hemoglobin carbonyl content and DNA damage) in metabolic syndrome were reversed to almost normal levels by glycyrrhizin. The decreased levels of peroxisome proliferator activated receptor (PPAR) and glucose transporter 4 (GLUT4) proteins in skeletal muscle of metabolic syndrome group were elevated by glycyrrhizin, indicating improved fatty acid oxidation and glucose homeostasis.

Effect of Berberine on Expression of Hepatocyte Nuclear Factor-4α in Rats with Fructose-induced Insulin Resistance / 华中科技大学学报（医学）（英德文版）

The effects of berberine on the expression of hepatocyte nuclear factor-4α (HNF-4α) in liver of rats with fructose-induced insulin resistance and the molecular mechanism of berberine preventing insulin resistance were investigated. The experimental animals were divided into two groups of 16 animals each. The control group received a control routine diet containing 60% carbohydrate, and the study group a high-fructose diet containing 60% fructose as the sole source of carbohydrate. At the end of 6 weeks these were each subdivided into two groups. One was administered with berberine [187.5mg/(kg·d) in 5g/L carboxymethyl cellulosel] by intragastric intubation and the other group was treated with a vehicle (5g/L carboxymethyl cellulose). The rats were fed on the same dietary regimen for the next 4 weeks. After the experimental period of 10 weeks, plasma glucose, insulin and triglyceride levels were measured. HOMA insulin resistance index (HOMA-IR) was assayed. Immunohistochemistry, semiquantitative RT-PCR and western blot were used to detect the expression of HNF-4α in liver. Compared with control diet, fructose feeding induced hyperinsulinemia, HOMA-IR and increased triglyceride (all P<0.01). Berberine prevented the rise in plasma insulin (P<0.01), HOMA-IR (P<0.01) and triglyceride (P<0.05) in the fructose-fed rats. No change in plasma glucose was seen among these groups. The mRNA and protein expression of HNF-4α was decreased in the fructose-fed rats, but berberine could promote its expression. It was concluded that berberine could prevent fructose-induced insulin resistance in rats possibly by promoting the expression HNF-4α in liver.

Arecoline improved glucose and lipid metabolism in type 2 diabetic rats / 中国药理学通报

Aim To investigate the effects of arecoline on glucose and lipid metabolism in type 2 diabetic rats and its mechanisms in glucose metabolism.Methods A type 2 diabetic rat model was established by fed with high fructose-high fat diet.The animals were randomly divided into 7 groups: control group,high fructose-high fat diet group(HF)and high fructose-high fat diet+arecoline(1 mg?kg-1,5 mg?kg-1,10 mg?kg-1,20 mg?kg-1,50 mg?kg-1)groups.The blood glucose,lipid level,hepatic function and liver histology were measured.The mRNA expression of liver glucose-6-phosphatase(G6Pase),phosphoenolpyruvate carboxykinase(PEPCK),Forkhead Box O1(FoxO1)and peroxisome proliferator-activated receptor-? coactlvator-1? (PGC-1?)were observed through RT-PCR.Results In comparison with the high fructose-high fat diet group,the fasting blood glucose and TC of the rats were significantly decreased by arecoline in a dose-dependment manner in high fructose-high fat diet+arecoline group.But hepatic function was damaged by 10 mg?kg-1,20 mg?kg-1 and 50 mg?kg-1 arecoline.The mRNA expression of hepatic G6Pase,PEPCK,FoxO1 and PGC-1? was decreased by treatment with 1 mg?kg-1 and 5 mg?kg-1 arecoline compared with the high fructose-high fat diet group.Conclusions Low dose arecoline can decrease fasting blood glucose and TC in type 2 diabettic rats,and the mechanism in glucose metabolism may be related to its effect on the inhibition of hepatic gluconeogenesis.

Effect of high-fructose diet on hypothalamic orexin system in rats / 中华内分泌代谢杂志

Orexin is a new neuropeptide related to diet intake and regulation of endocrine and metabolic functions. Rat model with insulin resistance (IR) was induced by high fructose diet and the extent of IR was assayed by hyperinsulinemic euglycemic clamp technique. The results showed that high fructose diet might induce IR and results in disturbance between orexin and leptin. Blood glucose, serum insulin, lipid metabolism and leptin may participate in the regulation of orexin.