Sucrose Diet Research Articles

Diabetogenic diet-induced insulin resistance associates with lipid droplet proteins and adipose tissue secretome, but not with sexual dimorphic adipose tissue fat accumulation in Wistar rats

The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.

Sugar content of diet does not buffer against chronic oral imidacloprid exposure in the alfalfa leafcutting bee (Hymenoptera: Megachilidae).

Bees are economically critical pollinators, but are declining broadly due to several stressors, including nontarget exposure to insecticides and deficiencies in nutrition. Understanding the simultaneous impact of stressors, particularly interactions between them, is critical to effectively conserving bees. Although behavioral effects of pesticides like neonicotinoids have received some attention in solitary bees, our understanding of how they are modulated by diet quality is limited. Furthermore, scarce data exist on what concentrations of orally ingested neonicotinoids elicit mortality in solitary bees. In a controlled exposure laboratory experiment, we investigated how diet quality, as sugar concentration, and chronic oral exposure to imidacloprid affect adult alfalfa leafcutting bees, Megachile rotundata (Fabricius). We provided individuals ad libitum with either 20 or 50% (m/m) sucrose syrups containing either 0, 30, or 300 ppb imidacloprid (measuring 0, 27, and 209 ppb via an ELISA assay). Over 5 wk, we tracked behavior and survivorship of individuals. Imidacloprid decreased survivorship in a dose-dependent fashion, but sucrose content did not affect survivorship, even in bees not fed imidacloprid. In the high imidacloprid treatment, 45% of bees were observed in a motionless supine position while still alive, with this effect appearing to be buffered against by the higher sucrose diet. Our results suggest that diets higher in sugar concentration may prevent an intermediate stage of poisoning, but do not ultimately extend longevity. In devising risk assessments for bees, it is important to consider that interactions between stressors may occur in the stages leading up to death even if survivorship is unaffected.

Metabolic cardio- and reno-protective effects of empagliflozin in a prediabetic rat model.

The mechanisms behind the cardiovascular and renal benefits of empagliflozin is not fully understood. The positive impact of the medication on cardiovascular mortality can not be solely attributed to its antidiabetic effect, with a metabolic mechanism possibly involved. To investigate the metabolic effects of empagliflozin treatment (10 mg/kg/day for 6 weeks), we used an adult male rat model with serious vascular complications associated with metabolic syndrome and prediabetes. Impaired glucose tolerance, severe albuminuria and impaired insulin sensitivity were induced by intragastric administration of methylglyoxal and high sucrose diet feeding for four months. Although empagliflozin decreased body weight, non-fasting glucose and insulin, glucagon levels remained unchanged. In addition, empagliflozin increased adiponectin levels (+40%; p < 0.01) and improved skeletal muscle insulin sensitivity. Increased non-esterified fatty acids (NEFA) in empagliflozin-treated rats is understood to generate ketone bodies. Empagliflozin increased β-hydroxybutyrate levels in serum (+66%; p < 0.05) and the myocardium (30%; p < 0.01), suggesting its possible involvement as an alternative substrate for metabolism. Empagliflozin switched substrate utilisation in the myocardium, diverting glucose oxidation to fatty acid oxidation. Representing another favorable effect, empagliflozin also contributed to decreased uric acid plasma levels (-19%; p < 0.05). In the kidney cortex, empagliflozin improved oxidative and dicarbonyl stress parameters and increased gene expression of β-hydroxybutyrate dehydrogenase, an enzyme involved in ketone body utilisation. In addition, empagliflozin decreased microalbuminuria (-27%; p < 0.01) and urinary neutrophil gelatinase-associated lipocalin (NGAL) excretion (-29%; p < 0.01). Our results reveal the important systemic metabolic effect of empagliflozin on alterations in substrate utilisation and on increased ketone body use in prediabetic rats. Improved oxidative and dicarbonyl stress and decreased uric acid are also possibly involved in the cardio- and reno-protective effects of empagliflozin.

Rhubarb Supplementation Prevents Diet-Induced Obesity and Diabetes in Association with Increased Akkermansia muciniphila in Mice.

Obesity and obesity-related disorders, such as type 2 diabetes have been progressively increasing worldwide and treatments have failed to counteract their progression. Growing evidence have demonstrated that gut microbiota is associated with the incidence of these pathologies. Hence, the identification of new nutritional compounds, able to improve health through a modulation of gut microbiota, is gaining interest. In this context, the aim of this study was to investigate the gut-driving effects of rhubarb extract in a context of diet-induced obesity and diabetes. Eight weeks old C57BL6/J male mice were fed a control diet (CTRL), a high fat and high sucrose diet (HFHS) or a HFHS diet supplemented with 0.3% (g/g) of rhubarb extract for eight weeks. Rhubarb supplementation fully prevented HFHS-induced obesity, diabetes, visceral adiposity, adipose tissue inflammation and liver triglyceride accumulation, without any modification in food intake. By combining sequencing and qPCR methods, we found that all these effects were associated with a blooming of Akkermansia muciniphila, which is strongly correlated with increased expression of Reg3γ in the colon. Our data showed that rhubarb supplementation is sufficient to protect against metabolic disorders induced by a diet rich in lipid and carbohydrates in association with a reciprocal interaction between Akkermansia muciniphila and Reg3γ.

Biophysical properties of mitochondrial calcium uniporter in metabolic syndrom

During excitation contraction coupling, calcium (Ca2 + ) released by ryanodine receptors (RyR2) enters in the mitochondria through the mitochondrial calcium uniporter (MCU). The MCU is a macromolecular complex composed by MCU and its regulatory proteins, MICU1 and MICU2. Under metabolic syndrome, mitochondrial Ca2+ uptake is decreased and we recently observed an increase in MICU1 expression after two weeks of High fat High Sucrose diet (HFS). To determine whether increase MICU1 expression impact the MCU function and may account for the decrease in mitochondrial Ca2+ uptake, our aim was to characterize the single channel electrophysiological properties of the MCU incorporated in planar lipid bilayer. MCU was purified from mice heart from control or 2 weeks HFS diet group. Mitochondria were isolated by differential centrifugation, and treated with proteinase K and digitonin to disrupt the outer mitochondrial membrane. Purified MCU was then incorporated in planar lipid bilayer to study its biophysical properties. Voltage steps were applied from -60 mV to +60 mV. At −40 mV, Ca2+ concentration was increased from 1 μM to 1 mM. Ruthenium red (RuR; 100 μM) was used to inhibit the single channel activity. At low Ca2+ concentration, the MCU purified from the HFS heart have a reduced number of opening events. The opening probability (Po) and the opening frequency (Fo) are significantly reduced compared to the control heart. However, at high Ca2+ concentration (100 μM) the MCU Po, the Fo and the number of events with high amplitude are increased whereas in control the single channels behavior remained unchanged. After 2 weeks of HFS diet, the increase of MICU1 expression affects biophysical properties of the MCU. Indeed, at low calcium concentrations MICU1 acts as a channel inhibitor and reduced MCU activity, but under high calcium concentrations MICU1 may acts as a channel activator for the MCU complex.

Diet reversal rescues mouse diabetic cardiomyopathy by counteracting the decreased reticulum-mitochondria interactions and the ensuing mitochondrial Ca2+ uptake impairment

Type 2 diabetic cardiomyopathy has been linked to Ca2+ signaling alterations, notably a decreased mitochondrial Ca2+ uptake. Recent discovery of Ca2+ microdomains between cardiac mitochondria and reticulum launched a new investigation avenue for cardiometabolic diseases. Hereby, we aimed to investigate if the mitochondrial Ca2+ mishandling is due to a dysregulation of the reticulum-mitochondria interactions or of the mitochondrial Ca2+ uniporter in the diabetic mouse heart. Mice fed for 16 weeks with a high fat high sucrose diet (HFHSD) displayed a cardiac insulin resistance combined to cardiac fibrosis, hypertrophy and contractile dysfunction (decreased strain rate) versus standard diet-fed mice (SD). Fractionation of HFHSD mice hearts revealed a decreased protein content of their mitochondria associated-reticulum membranes, together with a lower expression of tethering proteins quantified by mass spectrometry. On functional terms, reduced IP3R-VDAC proximity and co-immunoprecipitation were associated with a reduced IP3-stimulated Ca2+ transfer to mitochondria in isolated HFHSD cardiomyocytes, yet no changes in mitochondrial calcium uniporter protein expression and function were detected. Moreover, HFHSD cardiomyocytes displayed no significant changes in the reticular Ca2+ release level and the amplitude of cytosolic Ca2+ transients. Eight weeks of diet reversal restored the cardiac insulin signaling, MAM content, Ca2+ transfer and cardiac function in HFHSD mice. Therefore, our data indicate that disruption of the cardiac reticulum-mitochondria interactions is an early and reversible event impairing mitochondrial Ca2+ handling and contributing to the cardiac contractile dysfunction in the diabetic mouse heart, which could be counteracted by diet reversal.

Distinct Influence of Hypercaloric Diets Predominant with Fat or Fat and Sucrose on Adipose Tissue and Liver Inflammation in Mice

Overfeeding of a hypercaloric diet leads to obesity, diabetes, chronic inflammation, and fatty liver disease. Although limiting fat or carbohydrate intake is the cornerstone for obesity management, whether lowering fat or reducing carbohydrate intake is more effective for health management remains controversial. This study used murine models to determine how dietary fat and carbohydrates may influence metabolic disease manifestation. Age-matched C57BL/6J mice were fed 2 hypercaloric diets with similar caloric content, one with very high fat and low carbohydrate content (VHF) and the other with moderately high fat levels with high sucrose content (HFHS) for 12 weeks. Both groups gained more weight and displayed hypercholesterolemia, hyperglycemia, hyperinsulinemia, and liver steatosis compared to mice fed a normal low-fat (LF) diet. Interestingly, the VHF-fed mice showed a more robust adipose tissue inflammation compared to HFHS-fed mice, whereas HFHS-fed mice showed liver fibrosis and inflammation that was not observed in VHF-fed mice. Taken together, these results indicate macronutrient-specific tissue inflammation with excess dietary fat provoking adipose tissue inflammation, whereas moderately high dietary fat with extra sucrose is necessary and sufficient for hepatosteatosis advancement to steatohepatitis. Hence, liver and adipose tissues respond to dietary fat and sucrose in opposite manners, yet both macronutrients are contributing factors to metabolic diseases.

FORTIFIED DADIH (FERMENTED BUFFALO MILK) WITH VITAMIN D3 IMPROVES INTERLEUKIN-6 AND CAECUM SHORT CHAIN FATTY ACIDS ON DIET-INDUCED OBESE RAT

Objective: This study aims to determine the effect of fortified dadih with vitamin D3 on IL-6 expression level and the concentration of caecum SCFA in obese rats.&#x0D; Methods: A total of 30 male Sprague Dawley rats were divided into five equal groups: healthy-control-(K-), obese-control-(K+), obese-intervention-(X1, X2, and X3). K(+), X1, X2, and X3 were in obesity conditions, which was induced by a high-fat sucrose diet (HFSD) and K(-) as a healthy-control-group. Furthermore, vitamin D3-fortified dadih at doses of 4 g/200 g-body-weight/d, dadih only at doses of 4 g/200 g-body-weight/d, and vitamin D3 only at 36 IU/200 g-body-weight/d was administered to X1, X2, and X3 groups, respectively.&#x0D; Results: Treatment using fortified dadih with vitamin D3 showed significantly reduce weight gain (p&lt;0.05) compare to K(+) and X2. In addition, X1 showed a decreased level of Interleukin-6 expression (p&lt;0.05) than K(+), X2, and X3 groups but higher than K(-). Also, it showed the highest total SCFA, acetate, and propionate concentration (p&lt;0.05). However, a moderately negative correlation was discovered between the pair of total SCFA and Interleukin-6 expression, acetate and Interleukin-6 expression, SCFA and body weight, propionate and body weight, butyrate and body weight. On the contrary, a strong positive correlation was observed between the pair of Interleukin-6 expression levels and body weight.&#x0D; Conclusion: This study shows that fortified dadih with vitamin D3 from fermented foods improve the expression level of Interleukin-6 and increase the production of SCFA. Also, they improve intestinal homeostasis because of the increased SCFA production.

Attainment of Targets of the 20-Year Infancy-Onset Dietary Intervention and Blood Pressure Across Childhood and Young Adulthood: The Special Turku Coronary Risk Factor Intervention Project (STRIP).

We examined whether success in achieving the key targets of an infancy-onset 20-year dietary intervention was associated with blood pressure (BP) from infancy to young adulthood. In the prospective randomized STRIP (Special Turku Coronary Risk Factor Intervention Project; n=877 children), dietary counseling was provided biannually based on the Nordic Nutrition Recommendations primarily to improve the quality of dietary fat in children's diets and secondarily to promote intake of vegetables, fruits, and whole grains. Dietary data and BP were accrued annually from the age of 13 months to 20 years. The dietary targets for fat quality were defined as the ratio of saturated fatty acids to monounsaturated and polyunsaturated fatty acids <1:2 and intake of saturated fatty acids <10 E%, dietary fiber intake in the top age-specific quintile, and dietary sucrose intake as being in the lowest age-specific quintile. Attaining a higher number of the dietary targets was associated with lower systolic BP (mean [SE] systolic BP, 107.3 [0.3], 107.6 [0.3], 106.8 [0.3], and 106.7 [0.5] mm Hg in participants meeting 0, 1, 2, and 3 to 4 targets, respectively; P=0.03) and diastolic BP (mean [SE] diastolic BP, 60.4 [0.2], 60.5 [0.2], 59.9 [0.2], and 59.9 [0.3] mm Hg; P=0.02). When the lowest age-specific quintile of dietary cholesterol was added as an additional target, the association with systolic BP remained significant (P=0.047), but the association with diastolic BP attenuated (P=0.13). Achieving the key targets of an infancy-onset 20-year dietary intervention, reflecting dietary guidelines, was favorably albeit modestly associated with systolic and diastolic BP from infancy to young adulthood. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT00223600.

High-sucrose diet potentiates hyperaldosteronism and renal injury induced by stress in young adult rats.

Analyze the effect of stress and high-sucrose diet on serum aldosterone levels and the morphometric characteristics of the kidney in young adult rats. Wistar male rats aged 21 days old weaned were randomly assigned into four groups: control (C), stressed (St), high-sucrose diet (S30), and chronic restraint stress plus a 30% sucrose diet (St+S30). Rats were fed with a standard chow and tap water ad libitum (C group) or 30% sucrose diluted in water (S30 group) during eight weeks. The St and St+S30 groups were subject to restraint stress (1-hour daily in a plastic cylinder, 5days per week), four weeks before euthanasia. At 81days old, all animals were killed and blood samples and kidneys were collected. Stressed rats had an increase in the serum aldosterone and renal triacylglycerol, a decrease in the area of the renal corpuscle, glomeruli, proximal tubules, and aquaporin 2 expressions with loss of glomeruli. For its part, the high-sucrose diet decreased the area of the renal corpuscle, glomeruli, and aquaporin 2 expressions in the cortex. The combination of stress and high- sucrose diet maintained similar effects on the kidney as the stress alone, although it induced an increase in the creatinine levels and renal glycogen. Our results showed that chronic stress induces hyperaldosteronism and kidney injury. The intake of a high-sucrose diet may potentiate the renal injury promoted by stress.

Effects of maternal high-fat/high sucrose diet on hepatic lipid metabolism in rat offspring.

Maternal obesity and/or high‐fat diet during pregnancy predispose the offspring to metabolic disease. It is however unclear how pre‐natal and post‐natal exposure respectively affect the risk of hepatic steatosis and the trajectory towards non‐alcoholic steatohepatitis in the offspring. We investigate hepatic lipid metabolism and how these factors are related to metabolic outcome in new born and young rats. Rat dams were exposed to a high‐fat/high sucrose (HFHS) diet for 17 weeks prior to mating and during pregnancy. After birth, female offspring were killed and male offspring were cross‐fostered, creating four groups; Control‐born pups lactated by control (CC) or HFHS dams (CH) and HFHS‐born pups lactated by control (HC) or HFHS dams (HH). At 4 weeks of age, pups were killed and metabolic markers in plasma were assayed, together with hepatic lipid composition and expression of relevant genes. Female HFHS neonates had smaller livers at birth (P < .05), a reduced hepatic lipid content (P < .05) and altered lipid composition. The post‐natal environment dominated the metabolic profile in the male offspring at 4 weeks of age. Offspring exposed to a HFHS environment post‐natally had increased adiposity (P < .0001), increased hepatic triacylglycrol accumulation (P < .0001), and an altered lipid profile with elevated n‐6 polyunsaturated fatty acid (PUFA) levels (P < .0001) and a reduction in ceramide (P < .001) and monounsaturated fatty acid (MUFA) (P < .0001). In summary, maternal HFHS diet during gestation affects the hepatic lipid profile in neonates. The pre‐natal exposure becomes less pronounced in young male offspring at 4 weeks of age, where the post‐natal diet has the largest impact.

Abstract MP04: High Fat Diet Exposure Induces Epigenetic Modulation In The Brain Renin Angiotensin System

Cardiometabolic Diseases (CMD) are one of the highest causes of morbidity and mortality worldwide. In-utero, environmental insults can program brain’s progeny through changes in gene expression level affecting cardiometabolic functions. Methylation and demethylation of DNA take place by DNA methyltransferase (DNMT) and Ten eleven translocation (TET) enzymes, respectively. Expression of renin angiotensin system (RAS) on pre-autonomic neurons in the hypothalamus is believed to play a pivotal role in sympathetic activity controlling metabolic and blood pressure (BP) homeostasis. We hypothesize that perinatal exposure to high fat high sucrose diet (HFHSD) programs the brain RAS through methylation mechanisms that lead to autonomic dysfunction and hypersensitivity to CMD. C57BL6/J dams were fed HFHSD or regular diet (RD) and mated with RD sires. After weaning, offspring were raised on RD. Three-month old progeny underwent 24 h BP recording (telemetry), measurement of fasted blood glucose (FBG), assessment of autonomic function (pharmacological) and baroreflex sensitivity (sequence method). Mice were then sacrificed, and brains harvested for quantification of mRNA levels of DNMT, TET and RAS components in the hypothalamus. HFHSD-exposed male offspring showed elevation in systolic BP (140.2 ±1.9 vs. 131.2 ±2.4 mmHg, p=0.006), heart rate (611.3 ±7.8 vs 562.5 ±7 bpm, p&lt;0.0001) and FBG (172.7 ±6.3 vs. 142.6 ±6.3 mg/dl, p=0.018) but not females. Cardiac sympathetic activity was higher in HFHSD-exposed mice (-148 ±11.5 vs. -35.2 ±4.7 bpm, p&lt;0.05). Surprisingly, sympathetic vascular tone was only increased in HFHSD-exposed females (-64.6 ±5.7 vs. -36.7 ±2.9 mmHg, p&lt;0.05) while spontaneous baroreflex gain was improved in HFHSD-exposed males (5.3 ±0.7 vs. 2.6 ±0.4 msec/mmHg, p&lt;0.05). In the brain, DNMT1, DNMT3a and TET1, 2 and 3 mRNA expression were downregulated (p&lt;0.05) while AT 1a R and ACE2 genes were upregulated (p=0.02) in HFHSD-exposed mice. We conclude that perinatal exposure to a hypercaloric diet epigenetically programs the progeny’s brain through methylation leading to a pre-hypertensive and pre-diabetic phenotype associated with changes in the expression of RAS genes which could eventually result in increased susceptibility to CMD.

Ellagic Acid and Its Microbial Metabolite Urolithin A Alleviate Diet-Induced Insulin Resistance in Mice.

This work aims at evaluating the effect of dietary ellagic acid (EA) and its microbial metabolite urolithin A (UA) on glucose metabolism and insulin resistance (IR) in mice with diet-induced IR. DBA2J mice are fed a high fat/high sucrose diet (HF/HS) for 8 weeks to induce IR and then 0.1% EA, UA, or EA and UA (EA+UA) are added to the HF/HS-diet for another 8 weeks. UA significantly decreases fasting glucose and increases adiponectin compared with HF/HS-controls. During intraperitoneal insulin tolerance test, EA+UA significantly improve insulin-mediated glucose lowering effects at 15 and 120min and reduce blood triglycerides compared with HF/HS-controls. Serum free fatty acids are significantly decreased by EA, UA, and EA+UA. Differential expression of genes related to mitochondrial function by EA, UA, and EA+UA in liver and skeletal muscle is observed. Primary hepatocytes from IR-mice have higher proton leak, basal and ATP-linked oxygen consumption rates compared with healthy controls. EA and EA+UA but not UA reduce the proton leak in hepatocytes from IR-mice. EA and UA induce different metabolic benefits in IR mice. The effects of EA and UA on mitochondrial function suggest a potentially novel mechanism modulating metabolism.

Postprandial NMR-Based Metabolic Exchanges Reflect Impaired Phenotypic Flexibility across Splanchnic Organs in the Obese Yucatan Mini-Pig.

The postprandial period represents one of the most challenging phenomena in whole-body metabolism, and it can be used as a unique window to evaluate the phenotypic flexibility of an individual in response to a given meal, which can be done by measuring the resilience of the metabolome. However, this exploration of the metabolism has never been applied to the arteriovenous (AV) exploration of organs metabolism. Here, we applied an AV metabolomics strategy to evaluate the postprandial flexibility across the liver and the intestine of mini-pigs subjected to a high fat–high sucrose (HFHS) diet for 2 months. We identified for the first time a postprandial signature associated to the insulin resistance and obesity outcomes, and we showed that the splanchnic postprandial metabolome was considerably affected by the meal and the obesity condition. Most of the changes induced by obesity were observed in the exchanges across the liver, where the metabolism was reorganized to maintain whole body glucose homeostasis by routing glucose formed de novo from a large variety of substrates into glycogen. Furthermore, metabolites related to lipid handling and energy metabolism showed a blunted postprandial response in the obese animals across organs. Finally, some of our results reflect a loss of flexibility in response to the HFHS meal challenge in unsuspected metabolic pathways that must be further explored as potential new events involved in early obesity and the onset of insulin resistance.

Lauryl Gallate Activity and Streptococcus mutans: Its Effects on Biofilm Formation, Acidogenicity and Gene Expression.

Streptococcus mutans bacterium is implicated in the pathogenesis of dental caries due to the production of biofilm and organic acids from dietary sucrose. Despite the availability of various means of prophylaxis, caries still has a high worldwide prevalence. Therefore, it is important to find new pharmaceuticals to inhibit S. mutans biofilm formation and acidogenicity. The aim of the current study was to evaluate the activity of lauryl gallate (dodecyl gallate) against S. mutans acidogenicity, the expression of biofilm-associated genes, and biofilm development on solid surfaces (polystyrene, glass). The biofilm quantities produced by S. mutans bacteria were assessed using colorimetric and optical profilometry techniques. Acidogenicity was evaluated by measuring the pH of the biofilm growth medium with microelectrode. Assessment of the expression of gene coding for glucan-binding protein B (gbpB), glucosyltranferases B, -C, -D (gtfB, -C, -D), and the F-ATPase β subunit of F1 protein (atpD) was carried out using a quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The results demonstrate the capacity of lauryl gallate to significantly inhibit S. mutans acidogenicity and biofilm development on solid surfaces, in a dose-dependent manner, compared to untreated bacteria (p < 0.05). The highest activity of lauryl gallate occurred at a concentration of 98.98 µM, at which it suppressed biofilm formation by 100% and lowered pH levels by 98%. The effect of lauryl gallate treatment on gene expression changes, as demonstrated by our RT-qPCR data, was limited to the gtfD gene only, was a significant (48%) decrease in gene expression, obtained for the biofilm-producing bacteria, while a 300% increase in fold change for the same gene occurred in the planktonic cells. It is important to note that in previous studies we showed a broader effect of related derivatives. However, a similar magnitude of difference in effects between biofilm and planktonic cells for the atpD gene was obtained after treatment with octyl gallate and reverse magnitude for the same gene after treatment with ethyl gallate. Therefore, to ascertain the possible direct or indirect effects of lauryl gallate, as well as octyl gallate and ethyl gallate, more research is needed to examine the effects on the amount of enzymes and on the enzymatic activity of the products of the affected genes that are involved in the production and maintenance of biofilm by S. mutans.

Abstract 242: Multi-omics Profiling of Rat Offspring Exposed to Gestational Diabetes Reveals Cardiometabolic Disease Development With Age

Through unknown mechanisms, fetal exposure to gestational diabetes mellitus (GDM) increases the risk for cardiovascular disease development later in life. We hypothesize that fetal exposure to GDM induces alterations in cardiomyocyte metabolism and induces left ventricular (LV) dysfunction with age. GDM was induced in female rats with a high fat (45% kcal) and sucrose diet prior to mating, throughout pregnancy and lactation. Lean control females received a low fat (10% kcal) diet. Fetal rat ventricular cardiomyocytes (FRVC) were isolated from e20.5 offspring for U-13C glucose metabolic flux analysis, mitochondrial respiration and calcium handling. The cardiac transcriptome and metabolome were measured in 3-month old offspring. LV morphology and function was assessed in the offspring from e18 to 12-months of age by transthoracic ultrasound. Offspring exposed to GDM exhibited increased LV posterior wall thickness across their life course (fetal to 12-months of age; p&lt;0.05) and impaired LV filling beginning at 6-months of age (p&lt;0.05). Consistent with the development of diastolic dysfunction in vivo, alterations in calcium flux and sarcoplasmic reticulum-dependent calcium re-uptake (1.5-fold and 1.6-fold greater, respectively) were observed in FRVC isolated from GDM offspring (p&lt;0.05). When FRVC were treated with isoproterenol, U-13C glucose metabolic flux through glycolysis and the citric acid cycle was reduced in GDM offspring, compared to Lean controls. In 3-month old offspring serum metabolomics revealed reduced citric acid cycle intermediates and an altered acylcarnitine profile. These metabolic changes corresponded to alterations in gene expression patterns identified by RNASeq associated with glucose metabolism and fatty acid transport pathways (e.g. Irs2, Slc2a4, Pfkfb2, Pdk4 and Cpt1a) . Large-scale profiling revealed GDM induced alterations in the cardiac gene expression profile leading to modified serum metabolite levels in the offspring. These alterations corresponded with mitochondrial dysfunction, impaired cardiomyocyte metabolic flux and contractility, in concert with LV hypertrophy and diastolic dysfunction in the rat offspring. Our findings identify several mechanisms that link early-life GDM exposure to the development of cardiovascular disease later in life.

Immune Control of Animal Growth in Homeostasis and Nutritional Stress in Drosophila.

A large body of research implicates the brain and fat body (liver equivalent) as central players in coordinating growth and nutritional homeostasis in multicellular animals. In this regard, an underlying connection between immune cells and growth is also evident, although mechanistic understanding of this cross-talk is scarce. Here, we explore the importance of innate immune cells in animal growth during homeostasis and in conditions of nutrient stress. We report that Drosophila larvae lacking blood cells eclose as small adults and show signs of insulin insensitivity. Moreover, when exposed to dietary stress of a high-sucrose diet (HSD), these animals are further growth retarded than normally seen in regular animals raised on HSD. In contrast, larvae carrying increased number of activated macrophage-like plasmatocytes show no defects in adult growth when raised on HSD and grow to sizes almost comparable with that seen with regular diet. These observations imply a central role for immune cell activity in growth control. Mechanistically, our findings reveal a surprising influence of immune cells on balancing fat body inflammation and insulin signaling under conditions of homeostasis and nutrient overload as a means to coordinate systemic metabolism and adult growth. This work integrates both the cellular and humoral arm of the innate immune system in organismal growth homeostasis, the implications of which may be broadly conserved across mammalian systems as well.

Offspring of obese mice display enhanced intake and sensitivity for palatable stimuli, with altered expression of taste signaling elements

Maternal body mass index and gestational weight gain predict future obesity status of the offspring. In studies of both rodents and non-human primates, maternal obesity also predicts a preference for palatable foods in the offspring. In this study, we used C57BL/6J mice to investigate whether an underlying cause for an increase in palatable food consumption in the offspring of obese mice was a change in taste function. Adult female mice were fed a normal chow (NC) or a high fat diet (HFD) for 5 weeks before mating, then also during the gestation (3 weeks) and lactation (3 weeks) periods, with offspring always maintained on a normal chow diet; thus the only experience offspring had with high fat food was via maternal exposure. Offspring exhibited similar weight, blood glucose levels and baseline water and chow intake in adulthood. Taste response was assessed after reaching maturity, using brief-access taste testing, with female offspring of obese dams showing an enhanced response to sucrose, and both sexes consuming more sucrose, sucralose and high fat diet if from obese mothers. Offspring also exhibited increased taste bud expression of mRNA for sweet receptor subunits T1R (Taste receptor type) 2 and 3, as well as other markers associated with taste signaling. Taste morphology in both groups appeared similar. Results indicate that obesity in the mother may lead to unhealthy feeding behavior in the offspring, correlating with altered expression of taste signaling elements, which likely drive increased avidity for palatable foods.

High sucrose diet induces morphological, structural and functional impairments in the renal tubules of Drosophila melanogaster: A model for studying type-2 diabetes mediated renal tubular dysfunction

Continuous feeding of high dietary sugar is strongly associated with type 2 diabetes (T2D) and its secondary complications. Diabetic nephropathy (DN) is a major secondary complication that leads to glomerular and renal tubular dysfunction. The present study is aimed to investigate the effects of chronic exposure of high sugar diet (HSD) on renal tubules. Malpighian tubules (MTs), a renal organ of Drosophila, were used as a model in the study. Feeding of HSD develops T2D condition in Drosophila. The MTs showed structural abnormalities in 20 days of HSD fed flies. Impaired insulin signaling, oxidative stress, enhanced levels of AGE-RAGE and induction of apoptosis were observed in the MTs of these flies. Further, altered expression of transporters, enhanced uric acid level and reduced fluid secretion rate confirmed the impaired function of MTs in these flies. RNA-seq and RT-PCR analyses in the MTs of HSD fed-and control-flies revealed the altered expression of candidate genes that regulate several important pathways including extracellular matrix (ECM), advanced glycation end products-receptor for advanced glycation end products (AGE-RAGE), transforming growth factor β (TGF-β), galactose, starch and sucrose metabolism that are well known mediators of renal tubular dysfunction in DN patients. Disruption of insulin signaling in the MTs also causes renal tubular dysfunction similar to HSD fed flies. Overall, the study suggests that phenotypes observed in the MTs of HSD fed flies recapitulate several hallmarks of renal tubular dysfunction in DN patients. Therefore, we conclude that MTs of HSD fed flies may be used for deciphering the underlying mechanisms of T2D mediated renal tubular dysfunction.

Adaptive Fat Oxidation Is Coupled with Increased Lipid Storage in Adipose Tissue of Female Mice Fed High Dietary Fat and Sucrose.

Western diets high in fat and sucrose are associated with metabolic syndrome (MetS). Although the prevalence of MetS in women is comparable to that in men, metabolic adaptations in females to Western diet have not been reported in preclinical studies. This study investigates the effects of Western diet on risk factors for MetS in female mice. Based on our earlier studies in male mice, we hypothesized that dietary supplementation with extracts of Artemisia dracunculus L. (PMI5011) and Momordica charantia (bitter melon) could affect MetS risk factors in females. Eight-week-old female mice were fed a 10% kcal fat, 17% kcal sucrose diet (LFD); high-fat, high-sucrose diet (HFS; 45% kcal fat, 30% kcal sucrose); or HFS diet with PMI5011 or bitter melon for three months. Body weight and adiposity in all HFS groups were greater than the LFD. Total cholesterol level was elevated with the HFS diets along with LDL cholesterol, but triglycerides and free fatty acids were unchanged from the LFD. Over the three month period, female mice responded to the HFS diet by adaptive increases in fat oxidation energy in muscle and liver. This was coupled with increased fat storage in white and brown adipose tissue depots. These responses were enhanced with botanical supplementation and confer protection from ectopic lipid accumulation associated with MetS in female mice fed an HFS diet.