Leptin secretion after a high-fat meal in normal-weight rats: strong predictor of long-term body fat accrual on a high-fat diet

The objective of this study was to investigate meal-related endocrine changes that permit one to identify Sprague-Dawley rats at normal weight that are prone (OP) vs. resistant (OR) to obesity. In blood collected via chronic cardiac catheters, a 2-h high-fat meal (HFM, 50% fat, 40 kcal) at dark onset caused a significant increase in leptin, insulin, and triglycerides compared with premeal levels. Similar to patterns in already obese compared with lean rats on a high-fat diet, these meal-induced endocrine changes in normal-weight rats on lab chow were almost twofold larger in OP rats that, compared with OR rats, subsequently accumulated 100% more fat mass on a chronic high-fat diet. These exaggerated endocrine changes were similarly observed in blood collected using a simpler tail vein puncture procedure. In three separate experiments, the HFM-induced rise in leptin was found to be the strongest, positive correlate ( r = +0.58, +0.62 and +0.64) of long-term body fat accrual. The lowest (2–5 ng/ml) vs. highest (6–9 ng/ml) scores for this post-HFM leptin measurement identified distinct OR and OP subgroups, respectively, when they were similar in body weight (340–350 g), premeal leptin (2.6–3.4 ng/ml), and meal size (40 kcal). Subsequent tests in these normal-weight OP rats revealed a distinct characteristic compared with OR rats, namely, exaggerated HFM-induced rise in expression of the orexigenic peptide galanin in the paraventricular nucleus. Thus, with this HFM-induced leptin measurement, OP rats can be identified while still at normal weight and then investigated for mechanisms that contribute to their excessive body fat accrual on a high-fat diet.

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Behavioral and endocrine traits of obesity-prone and obesity-resistant rats on macronutrient diets

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1998.274.6.e1057 ◽

1998 ◽

Vol 274 (6) ◽

pp. E1057-E1066 ◽

Cited By ~ 10

Author(s):

Jian Wang ◽

Jesline T. Alexander ◽

Ping Zheng ◽

Hi Joon Yu ◽

Jordan Dourmashkin ◽

...

Keyword(s):

Body Weight ◽

Weight Gain ◽

Body Fat ◽

High Fat Diet ◽

Body Weight Gain ◽

Normal Weight ◽

Fat Intake ◽

Sprague Dawley ◽

Glucose Levels ◽

Sprague Dawley Rats

Patterns of eating behavior, body weight gain, and hormone changes were examined in normal-weight albino Sprague-Dawley rats on macronutrient diets. These diets consisted of either three separate jars with pure macronutrients, fat, carbohydrate and protein, from which to choose, or a single diet with different concentrations of fat and carbohydrate. Similar patterns on the choice-diet and single-diet paradigms were observed. During the first 7–10 days on these diets but not subsequently, the rats consuming a fat-rich diet exhibit significant hyperphagia, an increase in both total and fat intake that produces higher body weight gain. Compared with a 10% fat diet, a 30% fat diet is associated with a decline in insulin and corticosterone (CORT) levels, whereas a 60% fat diet produces an increase in circulating glucose. Levels of glucose are positively correlated with fat intake, and together these measures are consistently related to body fat. These relationships are most strongly expressed in rats that consume a fat-rich diet with >30% fat. Whereas insulin levels are also positively related to body fat, CORT is inversely related in these normal-weight subjects. In animals consuming a high-fat diet, a clear separation can be seen between “obesity-prone” (OP) rats with 100% greater body fat than “obesity-resistant” (OR) rats. The OP rats, which consume 15% more total calories, have significantly higher insulin and glucose levels. In animals that consume a diet with >30% fat, it is the OP but not the OR rats that exhibit a positive relation between fat intake, glucose levels, and body fat and reveal an additional association between carbohydrate intake, insulin, and body fat. Thus these rats on macronutrient diets exhibit distinct traits that relate behavior to hormone disturbances and adiposity and distinguish subjects that are prone vs. resistant to obesity.

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Effects of a Long-Term High-Fat Diet and Switching from a High-Fat to Low-Fat, Standard Diet on Hepatic Fat Accumulation in Sprague-Dawley Rats

Digestive Diseases and Sciences ◽

10.1007/s10620-008-0303-1 ◽

2008 ◽

Vol 53 (12) ◽

pp. 3206-3212 ◽

Cited By ~ 20

Author(s):

Katsuhisa Omagari ◽

Shigeko Kato ◽

Koichi Tsuneyama ◽

Chisato Inohara ◽

Yu Kuroda ◽

...

Keyword(s):

High Fat Diet ◽

Standard Diet ◽

Sprague Dawley ◽

High Fat ◽

Low Fat ◽

Fat Accumulation ◽

Sprague Dawley Rats ◽

Hepatic Fat

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Resistance to Dietary Obesity in Rats Given Different High-Energy Diets

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.76.5.271 ◽

2006 ◽

Vol 76 (5) ◽

pp. 271-279 ◽

Cited By ~ 6

Author(s):

Pérez de Heredia ◽

Garaulet ◽

Puy Portillo ◽

Zamora

Keyword(s):

Body Weight ◽

Adipose Tissue ◽

Body Fat ◽

High Fat Diet ◽

Wistar Rats ◽

High Energy ◽

Sprague Dawley ◽

High Fat ◽

Sprague Dawley Rats ◽

Dietary Obesity

Susceptibility to dietary obesity was studied in Wistar and Sprague-Dawley rats submitted to different high-energy diets. Experiment 1: female Sprague-Dawley rats were fed chow (n = 6) or a high-fat diet (n = 12) for 22 weeks. Experiment 2: Wistar rats were fed chow or a high-fat diet, and Sprague-Dawley rats were given chow, high-fat, sweet condensed milk, or cafeteria diets, for eight weeks (6 animals per group). Food intake and body weight were recorded weekly. Adipose tissue was collected from periovarian, mesenteric, and subcutaneous regions and adipocytes were isolated and measured. Both strains showed similar energy intake and body weight gain. Wistar rats reached greater final body fat contents than Sprague-Dawley rats, regardless of the type of diet. However, resistance to dietary obesity was found in 100% of cases in both experiments. None of the diets succeeded in increasing body fat accumulation when compared to control groups. All adipose tissue locations were equally unaffected, with periovarian fat cells being larger than those in mesenteric and subcutaneous regions in all the groups. In view of the strong resistance to obesity observed in rats, it should be important for researchers to transmit the difficulties of inducing dietary obesity in these animals, in order to prevent bias in science interpretation.

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Effects of Exercise Intensity on PGC-1α, PPAR-γ, and Insulin Resistance in Skeletal Muscle of High Fat Diet-fed Sprague-Dawley Rats

Journal of the Korean Society of Food Science and Nutrition ◽

10.3746/jkfn.2014.43.7.963 ◽

2014 ◽

Vol 43 (7) ◽

pp. 963-971

Author(s):

Hyun-Lyung Jung ◽

Ho-Youl Kang

Keyword(s):

Insulin Resistance ◽

Skeletal Muscle ◽

Exercise Intensity ◽

High Fat Diet ◽

Sprague Dawley ◽

High Fat ◽

Ppar Γ ◽

Sprague Dawley Rats

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The Effects of Maternal High Fat Diet on the Lingual CD36 Lipid Sensors of the Offspring Sprague Dawley Rats

Metabolism ◽

10.1016/j.metabol.2020.154497 ◽

2021 ◽

Vol 116 ◽

pp. 154497

Author(s):

Elif Günalan ◽

Meyli Ezgi Karagöz ◽

Bayram Yılmaz ◽

Burcu Gemici

Keyword(s):

High Fat Diet ◽

Sprague Dawley ◽

High Fat ◽

Sprague Dawley Rats ◽

Lipid Sensors

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Abstract 382: Anti-MAA Antibodies in Sprague Dawley Rats are Increased in Response to a High Fat Western Diet

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.33.suppl_1.a382 ◽

2013 ◽

Vol 33 (suppl_1) ◽

Author(s):

Michael J Duryee ◽

Anand Dusad ◽

Scott W Shurmur ◽

Michael D Johnston ◽

Robert P Garvin ◽

...

Keyword(s):

High Fat Diet ◽

Normal Diet ◽

Western Diet ◽

Sprague Dawley ◽

High Fat ◽

Sprague Dawley Rats ◽

Stable Plaque ◽

Circulating Antibodies ◽

Modified Proteins ◽

Progression Of Atherosclerosis

Introduction Malondialdehyde/Acetaldehyde (MAA) modified proteins have been suggested to play a role in the development/progression of atherosclerosis. Circulating antibodies directed against these proteins have recently been shown to be associated with the severity of the disease. More specifically, the isotype of the antibody to MAA correlated with either an acute MI (IgG) or stable plaque formation (IgA) formation. MAA is thought to form as a result of the oxidation of fat(s) and thus the concentration and antibody response should reflect the amount of fat in the diet. Objective The purpose of this study was to evaluate the antibody responses to MAA modified proteins following immunization and high fat western diet feeding in rats. Methods Male Sprague Dawley rats were immunized with MAA-modified protein weekly for 5 weeks and then assayed for antibodies to these proteins. Animals were then separated into the following groups: chow sham, chow MAA immunized, high fat sham, and high fat MAA immunized. The high fat animals were fed a Western diet with 2-thiouracil for 12 weeks, bled every 3 weeks, and serum assayed for the presence of circulating MAA antibodies. Results Prior to feeding with high fat diet, rats immunized with MAA-modified protein had a significant increase (P<0.001) in serum antibodies directed against these modified proteins compared to controls (N of 4 per group). Following feeding of high fat diet antibody concentrations increased 6 fold in the high fat MAA immunized group compared to the chow MAA immunized group (P<0.05). Antibodies in the high fat sham and chow sham had only minimal increases in antibodies to these proteins. Conclusions These data demonstrate that following immunization with MAA-modified proteins, circulating antibodies are produced that increase following consumption of a high fat Western diet. It suggests that MAA-modified proteins are produced at low levels following normal diet, producing antibodies which act as a normal clearance method for altered protein. When high fat consumption increases these antibody levels are increased in response to the oxidative stress. Implications Use of these antibodies as a biomarker in the future may help predict the onset or progression of atherosclerosis.

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