Prolonged Feeding Research Articles

FXR and TGR5 Agonists Ameliorate Liver Injury, Steatosis, and Inflammation After Binge or Prolonged Alcohol Feeding in Mice.

Bile acids (BAs) activate various dedicated receptors, including the farnesoid X receptor (FXR) and the Takeda G protein‐coupled receptor 5 (TGR5). The FXR agonist obeticholic acid (OCA) is licensed for the treatment of primary biliary cholangitis and has shown promising results in NASH patients, whereas TGR5 agonists target inflammation and metabolism. We hypothesized that FXR and/or TGR5 agonists may be therapeutic in early alcoholic liver disease (ALD) in mice, in which hepatic inflammation plays a major role. OCA, INT‐777, and INT‐767 are BA derivatives with selective agonist properties for FXR, TGR5, or both, respectively. These compounds were tested in two mouse models (3‐day binge model and prolonged Lieber DeCarli diet for 12 days) of early ALD. Serum alanine aminotransferase and liver histology were used to assess liver injury, Oil Red O staining of liver sections to assess steatosis, and real‐time polymerase chain reaction to assess changes in gene expression. In the ethanol binge model, treatment with OCA and INT‐777 decreased hepatic macrovesicular steatosis and protected from ethanol‐induced liver injury. After prolonged ethanol administration, mice treated with OCA, INT‐767, or INT‐777 showed decreased hepatic steatosis, associated with reduced liver fatty acid synthase protein expression, and protection from liver injury. Treatment with BA receptor agonists in both models of ethanol administration modulated lipogenic gene expression, and decreased liver interleukin‐1β mRNA expression associated with increased ubiquitination of NLRP3 inflammasome through cyclic adenosine monophosphate–induced activation of protein kinase A. Conclusion: OCA, INT‐767, or INT‐777 administration is effective in reducing acute and chronic ethanol‐induced steatosis and inflammation in mice, with varying degrees of efficacy depending on the duration of ethanol administration, indicating that both FXR and TGR5 activation can protect from liver injury in ALD models.

Hypothalamic Macrophage Inducible Nitric Oxide Synthase Mediates Obesity-Associated Hypothalamic Inflammation

In BriefLee et al. demonstrate in mice that, upon prolonged high-fat diet feeding, hypothalamic macrophages proliferate, expand their pool, and sustain hypothalamic inflammation. Moreover, they show that hypothalamic macrophage iNOS inhibition diminishes macrophage activation, astrogliosis, blood-brain-barrier permeability, and impaired glucose metabolism in diet-induced obese mice.

Origanum vulgare Terpenoids Induce Oxidative Stress and Reduce the Feeding Activity of Spodoptera littoralis.

Terpenoids are toxic compounds produced by plants as a defense strategy against insect herbivores. We tested the effect of Origanum vulgare terpenoids on the generalist herbivore Spodoptera littoralis and the response of the plant to herbivory. Terpenoids were analyzed by GC-FID and GC-MS and quantitative gene expression (qPCR) was evaluated on selected plant genes involved in both terpene biosynthesis. The insect detoxification response to terpenes was evaluated by monitoring antioxidant enzymes activity and expression of insect genes involved in terpene detoxification. O. vulgare terpenoid biosynthesis and gene expression was modulated by S. littoralis feeding. The herbivore-induced increased level of terpenoids (particularly carvacrol and p-cymene) interacted with the herbivore by decreasing larval survival and growth rate. The assimilation by S. littoralis of more than 50% of ingested terpenes correlated with the possible toxic effects of O. vulgare terpenoids. In choice test experiments, carvacrol and γ-terpinene mediated the larval feeding preferences, wherease the prolonged feeding on O. vulgare terpenoids (particularly on γ-terpinene) exerted relevant antinutritional effects on larvae. S. littoralis was found to react to O. vulgare terpenoids by increasing its antioxidant enzymes activities and gene expression, although this was not sufficient to sustain the toxicity of O. vulgare terpenoids.

Serum CK 18-M30 reflect liver pathological severity during NAFLD progression in a rat model

BackgroundCK 18-M30 was increased in patients with NAFLD. However, little is known about the relationship between CK 18-M30 and NAFLD progression. We aimed to analyze the variety of CK 18-M30 and other metabolism indices during NAFLD progression. Meanwhile, we aimed to investigate the correlation between CK 18-M30 and liver pathology during NAFLD progression. Materials and methodsRats were fed with high sucrose and high fat diet for building NAFLD models. We detected liver pathology by hematoxylin–eosin (HE) staining. We also detected serum CK 18-M30 and metabolism indices including liver enzymes, serum lipids and glycometabolism indices. ResultsThe aggravating degree of liver pathology appeared with prolonged feeding period. The relevance of CK 18-M30 to the severity of liver pathology were higher relative to other indices. ConclusionOur results suggested the significance of CK 18-M30 in the progression of NAFLD and provided new evidence for the early diagnosis and prognostic estimation of NAFLD.

Leptin is a physiological regulator of skeletal muscle angiogenesis and is locally produced by PDGFRα and PDGFRβ expressing perivascular cells.

Skeletal muscle capillarity is characteristically reduced in mature leptin receptor-deficient (Leprdb) mice, which has been attributed to the capillary loss that occurs secondary to metabolic dysfunction. Despite wide recognition of leptin as a pro-angiogenic molecule, the contribution of this adipokine has largely been overlooked in peripheral tissues. Moreover, prior documentation of leptin production within skeletal muscle indicates a potential paracrine role in maintaining local tissue homeostasis. Thus, we hypothesized that leptin is a physiological local paracrine regulator of skeletal muscle angiogenesis and that its production may be modulated by nutrient availability. Leprdb mice exhibited impaired angiogenesis during normal developmental maturation of skeletal myocytes, corresponding with an inability to increase vascular endothelial growth factor-A (VEGFA) mRNA and protein levels between 4 and 13 weeks. In cultured murine and human skeletal myocytes, recombinant leptin increased VEGFA mRNA levels. Leptin mRNA was detectable in skeletal muscle, increasing with prolonged high-fat feeding in mice, and with adiposity in human subjects. Platelet-derived growth factor receptor (PDGFR)α- and PDGFRβ- expressing perivascular cell populations were identified as leptin producing within skeletal muscle of mice and humans. Furthermore, in response to 2 weeks of high-fat feeding, PDGFRβ+ but not PDGFRα+ cells increased leptin production. We conclude that leptin is a physiological regulator of the capillary network in skeletal muscle and stimulates VEGFA production by skeletal myocytes. PDGFRβ expressing perivascular cells exhibit the capacity to act as local "nutrient-sensors" that couple nutrient status to leptin production in skeletal muscle.

How long are burn patients really NPO in the perioperative period and can we effectively correct the caloric deficit using an enteral feeding “Catch-up” protocol?

Objective“NPO at midnight” is a standard preoperative practice intended to reduce aspiration risk but can result in prolonged feeding interruptions in critically ill burn patients. Postoperative hyperalimentation in the form of a “catch-up” tube feeding protocol is routine. A retrospective review of our perioperative fasting practices and “catch-up” enteral feeding protocols was performed. MethodsPatients admitted to the Burn ICU from July 1st, 2015 to August 31st, 2016 were reviewed. Patients who had a protected airway in place, prescribed enteral nutrition, and underwent surgery were included. The time from NPO to surgical start (NPO-SS), NPO to feeding restart (NPO-FR), and calories received/prescribed were quantified. The efficacy of a postoperative catch-up feeding protocol was analyzed. ResultsThere were 41 patients that fit inclusion criteria with some undergoing multiple surgeries, yielding 109 surgeries/discrete perioperative events. The average total body surface area burn (38.1±23.6%), age (38.8±20.1years), ICU days (45.0±37.3 days), and ventilator days (35.1±33.8 days) were calculated. Average fasting durations of NPO-SS and NPO-FR were 9.3±3.1 and 14.2±4.1h, respectively. The average caloric deficit to prescribed calories ratio during the NPO-SS and NPO-FR periods were 1154±629/3534±851kcal and 1765±928/3534±851kcal, respectively. A post-operative catch-up protocol completely compensated for perioperative caloric deficits 68.8% (22/32) of the time. ConclusionsIn critically ill burn patients, a preoperative fast resulted in an average loss of greater than 50% of prescribed calories on the day of surgery. Clinicians should re-evaluate the standard practice of making preoperative patients “NPO at midnight”. An effective catch-up protocol can adequately reduce caloric deficits.

Feeding-Induced Cortisol Response in Newborn Infants.

Understanding the biological rhythms and stress response in sick newborns is important to minimize the negative effects of intensive care. Salivary cortisol has been used as a noninvasive surrogate marker of adrenal function; however, understanding of its control variables is insufficient. To investigate the presence of feeding-induced cortisol response and its control variables in newborns. Fifty-three newborn infants, who were between 30 and 40 weeks' corrected age and were on 3-hourly regular oral/enteral feeding, were recruited between January 2013 and June 2014. Saliva samples were collected before and 1 hour after regular feeding. Dependence of cortisol levels (adjusted for postnatal age) and their feeding-related elevation on clinical variables was assessed by using generalized estimating equations. Higher cortisol levels were associated with corrected age ≥37 weeks and saliva samples collected after feeding (both P < 0.001). Oral feeding was associated with a greater feeding-induced cortisol response compared with exclusive enteral feeding (P = 0.034), whereas a prolonged feeding duration (≥30 minutes) was associated with a reduced cortisol response compared with brief feeding (<30 minutes) (P < 0.001). Gestational age, corrected age, antenatal/postnatal glucocorticoids, type of milk, and daily feeding volume had no effect on cortisol response. Feeding-induced cortisol response was observed in newborns. The cortisol response was more prominent following oral feeding and was reduced with prolonged feeding. Future studies may investigate whether feeding-induced cortisol response plays a role in the acquisition of adrenal ultradian and diurnal rhythms.

Peroxisome Proliferator-Activated Receptor γ2 Controls the Rate of Adipose Tissue Lipid Storage and Determines Metabolic Flexibility

SummaryOne understudied function of white adipose tissue (AT) is its role in postprandial lipid buffering. In this study, we demonstrate that mice lacking the adipose tissue-specific transcription factor peroxisome proliferator-activated receptor γ2 (PPARγ2) exhibit a defect in their rate of adipose tissue lipid storage. Impaired adipose tissue storage rate reduces metabolic flexibility, without compromising fasted glucose tolerance or insulin sensitivity, even following prolonged high-fat feeding. However, acutely overfeeding PPARγ2-KO mice caused a 10-fold increase in insulin levels compared with controls. Although impaired adipose tissue storage rate did not result in insulin resistance in young mice, 1-year-old PPARγ2-KO mice developed skeletal muscle insulin resistance. Our data indicate that failed adipose tissue storage may occur prior to defects in glucose handling and that overfeeding protocols may uncover genes controlling adipose tissue storage rate, as opposed to capacity, and act as a diagnostic test for early-stage human metabolic disease.

Risk Factors for Necrotizing Enterocolitis: A Prospective Multicenter Case-Control Study

Background: The identification of independent clinical risk factors for necrotizing enterocolitis (NEC) may contribute to early selection of infants at risk, allowing for the development of targeted strategies aimed at the prevention of NEC. Objective: The objective of this study was to identify independent risk factors contributing to the development of NEC in a large multicenter cohort. Methods: This prospective cohort study was performed in 9 neonatal intensive care units. Infants born at a gestational age ≤30 weeks were included. Demographic and clinical data were collected daily until day 28 postnatally. Factors predictive of the development of NEC were identified using univariate and multivariable analyses in a 1: 5 matched case-control cohort. Results: In total, 843 infants (56 NEC cases) were included in this study. In the case-control cohort, univariate analysis identified sepsis prior to the onset of NEC and formula feeding to be associated with an increased risk of developing NEC, whereas the administration of antibiotics directly postpartum was inversely associated with NEC. In a multivariable logistic regression model, enteral feeding type and the number of days parenterally fed remained statistically significantly associated with NEC, whereas the administration of antibiotics directly after birth was associated with a lower risk of developing NEC. Conclusions: Formula feeding and prolonged (duration of) parenteral feeding were associated with an increased risk of NEC. Contrary to expectations, the initiation of treatment with antibiotics within 24 h after birth was inversely associated with NEC.

Hypothalamic Orexin Is Essential for Estrogenic Action on Glucose and Energy Metabolism in Diet-Induced Obese Mice

Decreased estrogen is a crucial pathogenic factor for type 2 diabetes in postmenopausal women; however, the precise mechanism remains unknown. Orexin is a major hypothalamic neuropeptides regulating energy/glucose metabolism, and its anti-obese effect is more evident in females. We therefore investigated whether estrogen prevents obesity and glucose intolerance through interaction with the orexin system. Ovariectomized (OVX) mice and female orexin knockout (OXKO) mice were prepared to examine the impact of estrogen and orexin deficiency, respectively. When maintained on 60% high fat diet (HFD) for 16-24 weeks, body weight gain, adipose tissue inflammation, and hepatic triglyceride contents were markedly increased in OXKO, compared to wild type (WT) mice. Ovariectomy did not significantly affect the body weight in WT and OXKO mice after prolonged HFD feeding. Importantly, the levels of proinflammatory markers (e.g., TNFα mRNA) in the white adipose tissues were increased mildly in sham-operated OXKO (Sham-OXKO) mice and remarkably in OVX-OXKO mice. The rank order of the severity was OVX-OXKO&amp;gt;Sham-OXKO&amp;gt;OVX-WT&amp;gt;Sham-WT. Moreover, Sirius-Red staining to evaluate the fatty liver disease (i.e., NAFLD/NASH) demonstrated mild and severe fibrosis in the liver of Sham-OXKO and OVX-OXKO mice, respectively, whereas there was no abnormality in OVX-WT and Sham-WT mice. In glucose tolerance test, 1) metabolic activity was greater in Sham-WT than OVX-WT mice, whereas no difference was observed between Sham-OXKO and OVX-OXKO mice on HFD, 2) intracerebroventricular injection of estrogen improved glucose tolerance in OVX-WT but not OVX-OXKO mice on HFD, suggesting that estrogen prevents glucose intolerance on HFD in an orexin-dependent manner. Taken together, orexin may play a fundamental role in the anti-obese and antidiabetic effects of estrogen. Therefore, orexin appears to be a novel therapeutic target to prevent metabolic disorders in postmenopausal women. Disclosure K. Kon: None. H. Tsuneki: None. S. Takata: None. T. Maeda: None. T. Wada: Research Support; Self; Sanwa Kagaku Kenkyusho Co., Ltd.. T. Sasaoka: None.

Skeletal Muscle Clock Is Essential for Nutrient-Sensing and Interorgan Metabolic Fuel Partitioning

The circadian clock exerts temporal control in metabolism and its disruption leads to the development of diabetes and obesity. Tissue-intrinsic clock circuits are integral components of global metabolic homeostasis, although how they sense nutrient signals to orchestrate metabolic flux is not clear. Skeletal muscle is major site for metabolic substrate oxidation, and its utilization of glucose and fatty acid depends on availability of nutrients accompanying feeding-fasting transitions. Interestingly, nearly 30% of rhythmic transcripts in skeletal muscle belongs to metabolism. By generating a mouse model with myocyte-selective ablation of the clock transcription activator Bmal1, here we show that cell-autonomous muscle clock plays an essential role in coordinating nutrient utilization with feeding-fasting induced cycles. Bmal1 in skeletal muscle was robustly induced by feeding, and its loss markedly impaired feeding-induced switch to glucose metabolism from fatty acid utilization. As a result, Bmal1-deficient muscle displays nearly 50% reduction of glucose oxidation whereas fatty acid oxidation was enhanced, resembling a constant fasting state. This metabolic shift was accompanied by muscle fiber type switching to an oxidative phenotype, and led to a remarkable resistance to hepatic lipid accumulation induced by prolonged fasting or high-fat diet feeding. In contrast, systemic fasting glucose levels in muscle Bmal1-deficient mice was elevated, which is due to a failure of suppressing hepatic glucose output as revealed by hyperinsulinemic-euglycemic glucose clamp study. Collectively, our results reveal a novel function of the Bmal1-driven muscle clock as a key metabolic sensor that coordinates metabolic fuel oxidation with oscillatory nutrient availability in fasting-feeding cycles. This temporal mechanism in orchestrating global nutrient flux may contribute to metabolic abnormalities induced by circadian misalignment. Disclosure K. Ma: None. S. Chatterjee: None. H. Yin: None.

Evaluation of hepatic integrin \u03b1v\u03b23 expression in non-alcoholic steatohepatitis (NASH) model mouse by 18F-FPP-RGD2 PET

BackgroundActivated hepatic stellate cells (HSCs), which express integrin αvβ3, are a major fibrogenic factor in NASH pathophysiology. 18F-labeled cyclic arginine-glycine-aspartic acid penta-peptide (18F-FPP-RGD2) has been used as a PET probe for tumors expressing integrin αvβ3. The aim of this study was to assess the potential of PET with 18F-FPP-RGD2 to detect hepatic integrin αvβ3 expression in non-alcoholic steatohepatitis (NASH) model mice.ResultsThirty-two male C57BL/6 mice aged 6 weeks were fed a choline-deficient, l-amino acid-defined, high-fat diet (CDAHFD) for 3 and 8 weeks. 18F-FPP-RGD2 PET imaging of the liver was performed at 3 and 8 weeks after CDAHFD feeding. After PET scanning, levels of hepatic integrin αvβ, 3α-smooth muscle actin (α-SMA), and collagen type 1 alpha 1(col1a1) were measured. Histopathological analysis of hepatic steatosis, inflammation, and fibrosis, as well as blood biochemistry analysis, was also performed. CDAHFD for 3 and 8 weeks produced a moderate-to-severe steatosis and inflammation of the liver in mice. NAFLD activity score (NAS) in mice fed the CDAHFD for 3 and 8 weeks were more than 4 indicating NASH or borderline NASH pathology. Fibrosis was observed only in mice fed the CDAHFD for 8 weeks. PET imaging showed that the hepatic standardized uptake value, SUV80–90 min, was increased with prolonged CDAHFD feeding compared with the respective controls (CDAHFD 3 weeks 0.32 ± 0.06 vs 0.48 ± 0.05, p < 0.01; CDAHFD 8 weeks 0.35 ± 0.04 vs 0.75 ± 0.07, p < 0.01, respectively). Prolonged CDAHFD feeding increased hepatic mRNA and protein levels of integrin αv and β3 at 3 and 8 weeks. Hepatic 18F-FPP-RGD2 uptake and amount of integrin αv and β3 protein were well correlated (r = 0.593, p < 0.05 and r = 0.835, p < 0.001, respectively). Hepatic 18F-FPP-RGD2 uptake also showed a positive correlation with Sirius red-positive area.ConclusionsThe hepatic uptake of 18F-FPP-RGD2 correlated well with integrin αv and β3 expression and histological fibrosis in a mouse model of NASH, suggesting the predictability of fibrosis in NASH pathology.

Prolonged High-Fat Diet Feeding of WHHLMI Rabbits does Not Aggravate Metabolic or Cardiac Dysfunction

Myocardial infarction (MI)-prone Watanabe hereditary hyperlipidemic (WHHLMI) rabbits were reported to spontaneously but slowly develop MI, associated with enhanced coronary atherosclerosis and metabolic syndrome features. Our aim was to accelerate these processes by exposing the rabbits to a high-fat diet (HFD) that was previously shown to induce insulin resistance and cardiac injury in rabbits. HFD feeding for one year was indeed associated with development of obesity (37% increases in body weight, as compared to 3.7% for control standard-fat diet, SFD). On HFD, liver weight and hepatic triglyceride content were significantly higher as compared to SFD, with mild steatosis. Glucose and insulin levels were not markedly different on SFD or HFD, however after 1 year of diet treatment, HFD-fed animals were more glucose intolerant as compared to SFD-fed rabbits. On SFD, the rabbits developed marked thoracic aorta stenosis and calcification of atherosclerotic lesions, which were not aggravated by HFD feeding. Cardiac function analysis by MRI and transthoracic echocardiography did not reveal significant differences between SFD and HFD fed rabbits. Thus, the metabolic and cardiac phenotype of WHHLMI rabbits was not aggravated by HFD feeding for one year, and the rabbits did not spontaneously develop diabetes or myocardial infarction.

Coenzyme A–mediated degradation of pyruvate dehydrogenase kinase 4 promotes cardiac metabolic flexibility after high-fat feeding in mice

Cardiac energy is produced primarily by oxidation of fatty acids and glucose, with the relative contributions of each nutrient being sensitive to changes in substrate availability and energetic demand. A major contributor to cardiac metabolic flexibility is pyruvate dehydrogenase (PDH), which converts glucose-derived pyruvate to acetyl-CoA within the mitochondria. PDH is inhibited by phosphorylation dependent on the competing activities of pyruvate dehydrogenase kinases (PDK1-4) and phosphatases (PDP1-2). A single high-fat meal increases cardiac PDK4 content and subsequently inhibits PDH activity, reducing pyruvate utilization when abundant fatty acids are available. In this study, we demonstrate that diet-induced increases in PDK4 are reversible and characterize a novel pathway that regulates PDK4 degradation in response to the cardiac metabolic environment. We found that PDK4 degradation is promoted by CoA (CoASH), the levels of which declined in mice fed a high-fat diet and normalized following transition to a control diet. We conclude that CoASH functions as a metabolic sensor linking the rate of PDK4 degradation to fatty acid availability in the heart. However, prolonged high-fat feeding followed by return to a low-fat diet resulted in persistent in vitro sensitivity of PDH to fatty acid-induced inhibition despite reductions in PDK4 content. Moreover, increases in the levels of proteins responsible for β-oxidation and rates of palmitate oxidation by isolated cardiac mitochondria following long-term consumption of high dietary fat persisted after transition to the control diet. We propose that these changes prime PDH for inhibition upon reintroduction of fatty acids.

Effect of Potato virus Y Presence in Solanum tuberosum (Solanales: Solanaceae) and Chenopodium album on Aphid (Hemiptera: Aphididae) Behavior.

This study establishes the effect of Potato Virus Y (PVY; Potyvirus) in potatoes, Solanum tuberosum L. (Solanales: Solanaceae) and in common-lambs' quarter Chenopodium album L. (Amaranthaceae) on Macrosiphum euphorbiae Thomas (Hemiptera: Aphididae) and Myzus persicae Sulzer (Hemiptera: Aphididae) behavior, host preference, transmission, and fitness under field and laboratory studies. In the field, several weeds, besides C. album, were collected, including: Sisymbrium altissimum L. (Brassicaceae), Erodium cicutarium L., Lactuca serriola L., Solanum sarrachoides Sendtner (Solanaceae), and S. dulcamara L. (Solanaceae). All weeds were serologically tested for the presence of PVY. From all weeds collected, 2.3 and 34% of C. album and S. sarrachoides, respectively, were PVY-positive. From those positive samples, 72% of the PVY found were PVYN; the remaining 28% was PVYO. In addition, several aphid species were collected from those weeds: Ovatus crataegarious Walker, Macrosiphum euphorbiae (Hemiptera: Aphididae), Hyalopterus pruni Geoffroy (Hemiptera: Aphididae), Rophalosiphum madis Fitch, and 'others aphid' species were collected. The highest number of aphids were collected in E. cicutarium, followed by S. dulcamara, L. serriola, S. altissimum, and C. album. In laboratory studies, PVY-infected C. album does not induce the production of aphids. Moreover, M. persicae did not appear to have a strong preference for either healthy or PVY-infected potato plant, but they did develop a preference for infected plants after prolonged feeding. M. persicae and M. euphorbiae transmitted PVY from C. album to S. tuberosum, 44 and 37.5 % of the time. Future research should seek to identify not only other sources and prevalence of PVY in the field but vector relationships. In insect-pathogen complex continues to persist in solanaceous field crops around the world.

Do Omega‐3 Fatty Acids Prevent the Development of Nonalcoholic Fatty Liver Disease?

The prevalence of obesity in the United States is at an all‐time high. It is estimated that 80–90% of the obese population has nonalcoholic fatty liver disease (NAFLD), which is characterized by excess lipid accumulation in the liver (when lipid exceeds &gt;7% of total liver mass). NAFLD can progress to nonalcoholic steatohepatitis (NASH) that includes development of hepatic inflammation, fibrosis, and cell death. Omega‐3 polyunsaturated fatty acids found in fish oils exhibit beneficial effects on regulating inflammation and may hold therapeutic potential as a preventative treatment of NAFLD.PURPOSEAssess the preventative effects of omega‐3 fatty acids on the development of NAFLD in high‐fat fed mice.METHODSMale C57BL/6 mice were randomized into four diet groups (n = 12/group) for 32 weeks: 10% low fat fish oil (LFFO), 41% high fat‐fish oil (HFFO), 10% low fat‐lard (LFL), or 41% high fat‐lard (HFL). At study completion, mice were euthanized and livers were frozen in O.C.T. compound in 2‐methylbutane while submerged in liquid nitrogen and stored at −80°C. Livers were cryosectioned at a thickness of 10 μm at −21°C. Fluorescence immunohistochemistry using Nile Red then allowed for the microscopic localization and quantification of neutral lipid droplets. The area of positive staining was calculated as a percentage of total section area, and an average neutral lipid droplet size was determined using Nikon Elements. A glucose tolerance test was performed at end study and the trapezoidal method was used to calculate total area under the curve (AUC).RESULTSBody weight in the HFL group was significantly greater than all other groups but glucose total AUC was only greater in HFL compared LFFO (p &lt; 0.05). In addition, body weight (p &lt; 0.05) and fasting glucose (p &lt; 0.05) was greater in HFFO compared to LFFO. Based on this data, we expect a diet rich in omega‐3 fatty acids will mitigate hepatic lipid accumulation during prolonged feeding of a high fat diet. It is expected that HFL will have significantly greater liver lipid accumulation than HFFO, LFFO, and LFL.CONCLUSIONSThese findings would suggest a protective effect of omega‐3 fatty acids on development of NAFLD.Support or Funding InformationSupported by NIH R21NS090282‐01This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Cardiometabolic response of juvenile rainbow trout exposed to dietary selenomethionine

Selenium (Se) is considered an essential trace element, involved in important physiological and metabolic functions for all vertebrate species. Fish require dietary concentrations of 0.1–0.5 μg Se/g dry mass (d.m.) to maintain normal physiological and selenoprotein function, however concentrations exceeding 3 μg/g d.m. have been shown to cause toxicity. As Se is reported to have a narrow margin between essentiality and toxicity, there is growing concern surrounding the adverse effects of elevated Se exposure caused by anthropogenic activities. Previous studies have reported that elevated dietary exposure of fish to selenomethionine (Se-Met) can cause significant cardiotoxicity and alter aerobic metabolic capacity, energy homeostasis and swimming performance. The goal of this study aims to further investigate mechanisms of sublethal Se-Met toxicity, particularly potential underlying cardiovascular and metabolic implications of chronic exposure to environmentally relevant concentrations of dietary Se-Met in juvenile rainbow trout (Oncorhynchus mykiss). Juvenile rainbow trout were fed either control food (1.3 μg Se/g d.m.) or Se-Met spiked food (6.4, 15.8 or 47.8 μg Se/g d.m.) for 60 d at 3% body weight per day. Following exposure, ultrahigh resolution B-mode and Doppler ultrasound was used to characterize cardiac function in vivo. Chronic dietary exposure to Se-Met significantly increased stroke volume, cardiac output, and ejection fraction. Fish fed with Se-Met spiked food had elevated liver glycogen and triglyceride stores, suggesting impaired energy homeostasis. Exposure to Se-Met significantly decreased mRNA abundance of citrate synthase (CS) in liver and serpin peptidase inhibitor, clad H1 (SERPINH) in heart, and increased mRNA abundance of sarcoplasmic reticulum calcium ATPase (SERCA) and key cardiac remodelling enzyme matrix metalloproteinase 9 (MMP9) in heart. Taken together, these responses are consistent with a compensatory cardiac response to increased susceptibility to oxidative stress, namely a decrease in ventricular stiffness and improved cardiac function. These cardiac alterations in trout hearts were linked to metabolic disruption in other major metabolic tissues (liver and skeletal muscle), impaired glucose tolerance with increased levels of the toxic glucose metabolite, methylglyoxal, increased lipid peroxidation in skeletal muscle, development of cataracts and prolonged feeding behaviour, indicative of visual impairment. Therefore, although juvenile rainbow trout hearts were apparently able to functionally compensate for adverse metabolic and anti-oxidant changes after chronic dietary exposure Se-Met, complications associated with hyperglycemia in mammalian species were evident and would threaten survival of juvenile and adult fish.

Early life nutrition, glycemic and anthropometric profiles of children exposed to gestational diabetes mellitus in utero

• This study showed that prolonged infant feeding with breast milk, at least >8 months, is associated with lower A1C levels in children exposed to GDM . • Neither exclusive breastfeeding duration nor the timing of solid food introduction was associated with glycemic or anthropometric profile of children. • These results suggest that the impact of in utero exposure to GDM can be partly attenuated by prolonged breastfeeding duration during early life.

Ontogenetic habitat shift of age-0 Japanese flounder Paralichthys olivaceus on the Pacific coast of northeastern Japan: differences in timing of the shift among areas and potential effects on recruitment success

Ontogenetic habitat shift and feeding habits in the shallow (< 15 m) and deep (30–80 m) habitats of age-0 Japanese flounder Paralichthys olivaceus in Sendai Bay, the Pacific coast of northeastern Japan, were examined to understand the mechanisms that potentially enable area-specific high recruitment success. The flounder was able to use the shallow nursery habitat for about 1 year, until the next summer of their settlement (June–August) when they had reached 250 mm total length (TL). In addition, age-0 flounder between 150 and 250 mm TL used both shallow and deep habitats from winter to the next summer of their settlement, where species, size, and availability of potential food and susceptibility to predators are considerably different. These area-specific characteristics in Sendai Bay are clearly different from other areas around Japan that have been described in the literature: shorter residence in the shallow habitat and smaller size at emigration to the deep habitat. The characteristics in Sendai Bay seem to be enabled by prolonged good feeding conditions in the shallow habitat, which result from an abundant food supply and relatively lower temperature that does not exceed the uppermost temperature (25 °C) for maximum growth of the age-0 flounder. We consider that the prolonged better feeding conditions in the shallow habitat in the study area for ca. 1 year after settlement contribute to higher recruitment success.

Modification of chrysanthemum odour and taste with chrysanthemol synthase induces strong dual resistance against cotton aphids.

SummaryAphids are pests of chrysanthemum that employ plant volatiles to select host plants and ingest cell contents to probe host quality before engaging in prolonged feeding and reproduction. Changes in volatile and nonvolatile metabolite profiles can disrupt aphid–plant interactions and provide new methods of pest control. Chrysanthemol synthase (CHS) from Tanacetum cinerariifolium represents the first committed step in the biosynthesis of pyrethrin ester insecticides, but no biological role for the chrysanthemol product alone has yet been documented. In this study, the TcCHS gene was over‐expressed in Chrysanthemum morifolium and resulted in both the emission of volatile chrysanthemol (ca. 47 pmol/h/gFW) and accumulation of a chrysanthemol glycoside derivative, identified by NMR as chrysanthemyl‐6‐O‐malonyl‐β‐D‐glucopyranoside (ca. 1.1 mM), with no detrimental phenotypic effects. Dual‐choice assays separately assaying these compounds in pure form and as part of the headspace and extract demonstrated independent bioactivity of both components against the cotton aphid (Aphis gossypii). Performance assays showed that the TcCHS plants significantly reduced aphid reproduction, consistent with disturbance of aphid probing activities on these plants as revealed by electropenetrogram (EPG) studies. In open‐field trials, aphid population development was very strongly impaired demonstrating the robustness and high impact of the trait. The results suggest that expression of the TcCHS gene induces a dual defence system, with both repellence by chrysanthemol odour and deterrence by its nonvolatile glycoside, introducing a promising new option for engineering aphid control into plants.