A high-fat diet rich in corn oil exaggerates the infarct size and memory impairment in rats with cerebral ischemia and is associated with suppressing osteopontin and Akt, and activating GS3Kβ, iNOS, and NF-κB

Fucoidan, a natural sulfated polysaccharide, displays various biological activities including antioxidant properties. We examined the neuroprotective effect of fucoidan against transient global cerebral ischemia (tGCI) in high-fat diet (HFD)-induced obese gerbils and its related mechanisms. Gerbils received HFD for 12 weeks and fucoidan (50 mg/kg) daily for the last 5 days during HFD exposure, and they were subjected to 5-min tGCI. Pyramidal cell death was observed only in the CA 1 area (CA1) of the hippocampus in non-obese gerbils 5 days after tGCI. However, in obese gerbils, pyramidal cell death in the CA1 and CA2/3 occurred at 2 days and 5 days, respectively, after tGCI. In the obese gerbils, oxidative stress indicators (dihydroethidium, 8-hydroxyguanine and 4-hydroxy-2-nonenal) were significantly enhanced and antioxidant enzymes (SOD1 and SOD2) were significantly reduced in pre- and post-ischemic phases compared to the non-obese gerbils. Fucoidan treatment attenuated acceleration and exacerbation of tGCI-induced neuronal death in the CA1–3, showing that oxidative stress was significantly reduced, and antioxidant enzymes were significantly increased in pre- and post-ischemic phases. These findings indicate that pretreated fucoidan can relieve the acceleration and exacerbation of ischemic brain injury in an obese state via the attenuation of obesity-induced severe oxidative damage.

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Maternal high-fat diet during pregnancy and lactation reduces the appetitive behavioral component in female offspring tested in a brief-access taste procedure

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00419.2013 ◽

2014 ◽

Vol 306 (7) ◽

pp. R499-R509 ◽

Cited By ~ 14

Author(s):

Yada Treesukosol ◽

Bo Sun ◽

Alexander A. Moghadam ◽

Nu-Chu Liang ◽

Kellie L. Tamashiro ◽

...

Keyword(s):

Opioid Receptor ◽

High Fat Diet ◽

Corn Oil ◽

Sucrose Concentration ◽

Maternal Diet ◽

Female Offspring ◽

Chow Diet ◽

High Fat ◽

Endogenous Opioid ◽

Pregnancy And Lactation

Maternal high-fat diet appears to disrupt several energy balance mechanisms in offspring. Here, female offspring from dams fed a high-fat diet (HF) did not significantly differ in body weight compared with those fed chow (CHOW), when weaned onto chow diet. Yet when presented with both a chow and a high-fat diet, high-fat intake was significantly higher in HF compared with CHOW offspring. To assess taste-based responsiveness, offspring (12 wk old) were tested in 30-min sessions (10-s trials) to a sucrose concentration series in a brief-access taste test. Compared with CHOW, the HF offspring initiated significantly fewer trials but did not significantly differ in the amount of concentration-dependent licking. Thus, rather than affect lick response (consummatory), maternal diet affects spout approach (appetitive), which may be attributed to motivation-related mechanisms. Consistent with this possibility, naltrexone, an opioid receptor antagonist, further reduced trial initiation, but not licking in both groups. With naltrexone administration, the group difference in trial initiation was no longer evident, suggesting differences in endogenous opioid activity between the two groups. Relative expression of μ-opioid receptor in the ventral tegmental area was significantly lower in HF rats. When trial initiation was not required in one-bottle intake tests, no main effect of maternal diet on the intake of sucrose and corn oil emulsions was observed. Thus, the maternal high-fat diet-induced difference in diet preference is not likely due to changes in the sensory orosensory component of the taste stimulus but may depend on alterations in satiety signals or absorptive mechanisms.

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Effects of a high-fat diet and voluntary wheel running on gluconeogenesis and lipolysis in rats

Journal of Applied Physiology ◽

10.1152/jappl.1999.86.4.1374 ◽

1999 ◽

Vol 86 (4) ◽

pp. 1374-1380 ◽

Cited By ~ 26

Author(s):

Deborah A. Podolin ◽

Yuren Wei ◽

Michael J. Pagliassotti

Keyword(s):

High Fat Diet ◽

Corn Oil ◽

Wheel Running ◽

Whole Body ◽

Free Access ◽

Fat Pad ◽

High Fat ◽

Voluntary Wheel Running ◽

Voluntary Wheel

The purpose of the present study was to determine the effects of diet composition and exercise on glycerol and glucose appearance rate (Ra) and on nonglycerol gluconeogenesis (Gneo) in vivo. Male Wistar rats were fed a high-starch diet (St, 68% of energy as cornstarch, 12% corn oil) for a 2-wk baseline period and then were randomly assigned to one of four experimental groups: St ( n = 7), high-fat (HF; 35% cornstarch, 45% corn oil; n = 8), St with free access to exercise wheels (StEx; n = 7), and HF with free access to exercise wheels (HFEx; n = 7). After 8 wk, glucose Rawhen using [3-3H]glucose, glycerol Rawhen using [2H5]glycerol (estimate of whole body lipolysis), and [3-13C]alanine incorporation into glucose (estimate of alanine Gneo) were determined. Body weight and fat pad mass were significantly ( P < 0.05) decreased in exercise vs. sedentary animals only. The average amount of exercise was not significantly different between StEx (3,212 ± 659 m/day) and HFEx (3,581 ± 765 m/day). The ratio of glucose to alanine enrichment and absolute glycerol Ra(μmol/min) were higher ( P < 0.05) in HF and HFEx compared with St and StEx rats. In separate experiments, the ratio of3H in C-2 to C-6 of glucose from3H2O (estimate of Gneo from pyruvate) was also higher ( P < 0.05) in HF ( n = 5) and HFEx ( n = 5), compared with St ( n = 5) and StEx ( n = 5) rats. Voluntary wheel running did not significantly increase estimated alanine or pyruvate Gneo or absolute glycerol Ra. Voluntary wheel running increased ( P< 0.05) glycerol Rawhen normalized to fat pad mass. These data suggest that a high-fat diet can increase in vivo Gneo from precursors that pass through pyruvate. They also suggest that changes in the absolute rate of glycerol Ramay contribute to the high-fat diet-induced increase in Gneo.

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Decreased responsiveness to dietary fat in Otsuka Long-Evans Tokushima fatty rats lacking CCK-A receptors

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1999.277.4.r1144 ◽

1999 ◽

Vol 277 (4) ◽

pp. R1144-R1151 ◽

Cited By ~ 21

Author(s):

Gary J. Schwartz ◽

Andrew Whitney ◽

Chris Skoglund ◽

Thomas W. Castonguay ◽

Timothy H. Moran

Keyword(s):

Dietary Fat ◽

High Fat Diet ◽

Corn Oil ◽

High Fat ◽

Oletf Rats ◽

Glucose Intake ◽

Long Evans ◽

Fat Feeding ◽

Cck Release ◽

Subsequent Intake

Adult Otsuka Long-Evans Tokushima fatty (OLETF) rats lack functional cholecystokinin A (CCK-A) receptors, are diabetic, hyperphagic, and obese, and have patterns of ingestion consistent with a satiety deficit secondary to CCK insensitivity. Because dietary fat potently stimulates CCK release, we examined how dietary fat modulates feeding in adult male OLETF rats and their lean [Long-Evans Tokushima (LETO)] controls. High-fat feeding produced sustained overconsumption of high-fat diet (30% corn oil in powdered chow) over a 3-wk period in OLETF but not LETO rats. We then assessed the ability of gastric gavage (5 ml, 1–2 kcal/ml × 15 s) or duodenal preloads (1 kcal/ml, 0.44 ml/min × 10 min) of liquid carbohydrate (glucose), protein (peptone), or fat (Intralipid) to suppress subsequent 30-min 12.5% glucose intake in both strains. In OLETF rats, gastric and duodenal fat preloads were significantly less effective in suppressing subsequent intake than were equicaloric peptone or glucose. These results demonstrate that OLETF rats fail to compensate for fat calories and suggest that their hyperphagia and obesity may stem from a reduced ability to process nutrient-elicited gastrointestinal satiety signals.

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Mammary Cancer Promotion and MAPK Activation Associated With Consumption of a Corn Oil-Based High-Fat Diet

Nutrition and Cancer ◽

10.1207/s15327914nc3402_3 ◽

1999 ◽

Vol 34 (2) ◽

pp. 140-146 ◽

Cited By ~ 10

Author(s):

Zaisen Wang ◽

Hongying Pei ◽

Mark Kaeck ◽

Junxuan Lu

Keyword(s):

High Fat Diet ◽

Mammary Cancer ◽

Corn Oil ◽

High Fat ◽

Mapk Activation

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Leucine imparts cardioprotective effects by enhancing mTOR activity and mitochondrial fusion in a myocardial ischemia/reperfusion injury murine model

Diabetology & Metabolic Syndrome ◽

10.1186/s13098-021-00755-z ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Atsushi Morio ◽

Rie Tsutsumi ◽

Shiho Satomi ◽

Takashi Kondo ◽

Hirotsugu Miyoshi ◽

...

Keyword(s):

Infarct Size ◽

High Fat Diet ◽

Ischemia Reperfusion ◽

Mitochondrial Fusion ◽

Control Group ◽

Obese Mice ◽

High Fat ◽

Rat Cardiomyocytes ◽

Cardioprotective Effects ◽

Mtor Activity

Abstract Background Coronary artery disease is a leading cause of morbidity and mortality among patients with diabetes. Previously, we demonstrated that branched-chain amino acids (BCAAs) showed cardioprotective effects against cardiac ischemia/reperfusion (I/R) injury. A recent study suggested that leucine (Leu), a BCAA, is a key amino acid involved in mammalian target of rapamycin (mTOR) activity and mitochondrial function. However, whether Leu has cardioprotective effects on diabetic hearts is unclear. In this study, we examined the preconditioning effect of Leu treatment on high-fat diet (HFD)-induced obese mouse which simulate prediabetic heart. Methods In vivo mice models of I/R injury were divided into the following groups: control, mTOR+/−, and high-fat diet (HFD)-induced obese groups. Mice were randomly administered with Leu, the mTOR inhibitor rapamycin (Rap), or Leu with Rap. Isolated rat cardiomyocytes were subjected to simulated I/R injury. Biochemical and mitochondrial functional assays were performed to evaluate the changes in mTOR activity and mitochondrial dynamics caused by Leu treatment. Results Leu-treated mice showed a significant reduction in infarct size when compared with the control group (34.8% ± 3.8% vs. 43.1% ± 2.4%, n = 7, p < 0.05), whereas Rap-treated mice did not show the protective effects of Leu. This preconditioning effect of Leu was attenuated in mTOR+/− mice. Additionally, Leu increased the percentage of fused mitochondria and the mitochondrial volume, and decreased the number of mitochondria per cell in isolated cardiomyocytes. In HFD-induced obese mice, Leu treatment significantly reduced infarct size (41.0% ± 1.1% vs. 51.0% ± 1.4%, n = 7, p < 0.05), which was not induced by ischemic preconditioning, and this effect was inhibited by Rap. Furthermore, we observed enhanced mTOR protein expression and mitochondrial fusion with decreased reactive oxygen species production with Leu treatment in HFD-induced obese mice, but not in mTOR+/− mice. Conclusions Leu treatment improved the damage caused by myocardial I/R injury by promoting mTOR activity and mitochondrial fusion on prediabetic hearts in mice.

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Ventromedial hypothalamic knife-cut lesions in rats resistant to dietary obesity

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1984.246.6.r943 ◽

1984 ◽

Vol 246 (6) ◽

pp. R943-R948 ◽

Cited By ~ 1

Author(s):

J. Oku ◽

G. A. Bray ◽

J. S. Fisler ◽

R. Schemmel

Keyword(s):

Body Weight ◽

Adipose Tissue ◽

Food Intake ◽

High Fat Diet ◽

Corn Oil ◽

High Fat ◽

Interscapular Brown Adipose Tissue ◽

Brown Adipose ◽

Dietary Obesity

The effects of ventromedial hypothalamic (VMH) knife-cut lesions on food intake and body weight of S 5B/Pl rats, which are normally resistant to obesity when eating a high-fat diet, were examined in two experiments. In the first experiment body weight increased only slightly after VMH knife-cut lesions when animals were fed pelleted laboratory chow or a 10% corn oil diet. When eating the 30% corn oil diet, however, body weight increased in the VMH knife-cut rats. In the second experiment VMH knife-cut lesions produced a small weight gain in rats fed the 10% fat diet; this manipulation also increased food intake and disrupted the normal diurnal feeding pattern. Changes in the weight of the liver, interscapular brown adipose tissue, and white adipose tissue paralleled the changes in body weight. Plasma insulin increased in the rats eating the 30% corn oil diet ad libitum but not in the VMH-lesioned animals pair fed to the sham-operated rats. Incorporation of 3H from 3H2O into lipid was significantly increased in white fat of animals with VMH knife cuts. Similar results were obtained from incubation of adipose tissue in vitro with insulin and radioactively labeled glucose. These studies show that hypothalamic knife-cut lesions can remove the resistance of the S 5B/Pl rats to obesity when they are fed a high-fat diet.

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