High Dose of A Conjugated Linoleic Acid Mixture Increases Insulin Resistance in Rats Fed Either A Low Fat or A High Fat Diet

AbstractObesity and related diseases are becoming more prevalent. Conjugated linoleic acid (CLA) might be a useful coadjutant treatment helping to decrease fat mass. However, the precise impact of CLA is unclear because the decreased body fat mass is followed by an increase in insulin resistance. This study aimed to evaluate some of the consequences of a high dose of CLA in rats fed a normal low fat or a high fat diet for 30 days. Male Wistar rats were separated into 4 groups (each n = 10): Control group receiving 7% fat (soybean oil); CLA group receiving 4% soybean oil and 3% CLA mixture; animal fat (AF) group, receiving 45% fat (lard); and animal fat plus CLA (AF+CLA) group, receiving 42% lard and 3% CLA mixture. The CLA mixture contained 39.32 mole% c9,t11-CLA and 40.50 mole% t10,c12-CLA. After 30 days, both CLA groups (CLA and AF+CLA groups) developed insulin resistance, with an increase in glucose in the fasting state and in an insulin tolerance test. The CLA group had increased liver weight and percentage of saturated fatty acids in liver and adipose tissue. Feeding the high fat diet resulted in increased hepatic triacylglycerol accumulation and this was exacerbated by dietary CLA. It is concluded that a high dose of CLA mixture increases insulin resistance and exacerbates hepatic steatosis when combined with a high fat diet.

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Co-Administration of Conjugated Linoleic Acid and Rosiglitazone Increases Atherogenic Co-Efficient and Alters Isoprenaline-Induced Vasodilatation in Rats Fed High Fat Diet

Physiological Research ◽

10.33549/physiolres.933706 ◽

2018 ◽

pp. 729-740

Author(s):

B. K. CHAI ◽

Y. S. LAU ◽

B. J. LOONG ◽

M. M. RAIS ◽

K. N. TING ◽

...

Keyword(s):

Insulin Resistance ◽

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

High Fat Diet ◽

Normal Diet ◽

High Density Lipoproteins ◽

Oral Glucose ◽

Peroxisome Proliferator ◽

Sprague Dawley ◽

High Fat

The cis(c)-9, trans(t)-11 (c9,t11) and t10,c12 isomers of conjugated linoleic acid (CLA) have been reported as agonists of peroxisome proliferator-activated receptor (PPAR) and beneficial in lipidemia and glycemia. However, it is unclear whether CLA isomers enhance or antagonize effects of conventional drugs targeting PPAR. Male Sprague-Dawley rats were fed high fat diet (HFD) for 8 weeks and treated without or with CLA, rosiglitazone or both for 4 weeks. Oral glucose tolerance and surrogate markers of insulin resistance were not significantly different for all treatments compared to untreated normal diet (ND) or HFD group, except lipoprotein levels. The combination of CLA and rosiglitazone had suppressed levels of low and high density lipoproteins (46 % and 25 %, respectively), compared to HFD-alone. Conversely, the atherogenic co-efficient of the animals received HFD or HFD+rosiglitazone+CLA was 2-folds higher than ND, HFD+rosiglitazone or HFD+CLA. Isolated aortic rings from the combined CLA and rosiglitazone treated animals were less sensitive to isoprenaline-induced relaxation among endothelium-denuded aortas with a decreased efficacy and potency (Rmax=53±4.7 %; pEC50=6±0.2) compared to endothelium-intact aortas (Rmax=100±9.9 %; pEC50=7±0.2). Our findings illustrate that the combination of CLA and rosiglitazone precede the atherogenic state with impaired endothelium-independent vasodilatation before the onset of HFD-induced insulin resistance.

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Mixed conjugated linoleic acid sex‐dependently reverses high‐fat diet‐induced insulin resistance via the gut‐adipose axis

The FASEB Journal ◽

10.1096/fj.202002161rr ◽

2021 ◽

Vol 35 (4) ◽

Author(s):

Haoyu Li ◽

Pan Zhuang ◽

Yu Zhang ◽

Qiyang Shou ◽

Yanhua Lu ◽

...

Keyword(s):

Insulin Resistance ◽

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

High Fat Diet ◽

High Fat

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Conjugated linoleic acid and chromium lower body weight and visceral fat mass in high-fat-diet-fed mice

Lipids ◽

10.1007/s11745-006-5117-3 ◽

2006 ◽

Vol 41 (5) ◽

pp. 437-444 ◽

Cited By ~ 22

Author(s):

Arunabh Bhattacharya ◽

M. Mizanur Rahman ◽

Roger McCarter ◽

Marianne O'Shea ◽

Gabriel Fernandes

Keyword(s):

Body Weight ◽

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

Fat Mass ◽

Visceral Fat ◽

High Fat Diet ◽

Lower Body ◽

High Fat ◽

Lower Body Weight

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Antiobesity effect of PEGylated conjugated linoleic acid on high-fat diet-induced obese C57BL/6J (ob/ob) mice: attenuation of insulin resistance and enhancement of antioxidant defenses

The Journal of Nutritional Biochemistry ◽

10.1016/j.jnutbio.2008.02.001 ◽

2009 ◽

Vol 20 (3) ◽

pp. 187-194 ◽

Cited By ~ 16

Author(s):

Hyun-Seuk Moon ◽

Hong-Gu Lee ◽

Ji-Hye Seo ◽

Chung-Soo Chung ◽

Tae-Gyu Kim ◽

...

Keyword(s):

Insulin Resistance ◽

Linoleic Acid ◽

Conjugated Linoleic Acid ◽

High Fat Diet ◽

Antioxidant Defenses ◽

High Fat

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Dietary Isoliquiritigenin at a Low Dose Ameliorates Insulin Resistance and NAFLD in Diet-Induced Obesity in C57BL/6J Mice

International Journal of Molecular Sciences ◽

10.3390/ijms19103281 ◽

2018 ◽

Vol 19 (10) ◽

pp. 3281 ◽

Cited By ~ 4

Author(s):

Youngmi Lee ◽

Eun-Young Kwon ◽

Myung-Sook Choi

Keyword(s):

Insulin Resistance ◽

Energy Expenditure ◽

Body Fat ◽

Fat Mass ◽

High Fat Diet ◽

Plasma Cholesterol ◽

Cellular Respiration ◽

Body Fat Mass ◽

High Fat ◽

Diet Induced Obesity

Isoliquiritigenin (ILG) is a flavonoid constituent of Glycyrrhizae plants. The current study investigated the effects of ILG on diet-induced obesity and metabolic diseases. C57BL/6J mice were fed a normal diet (AIN-76 purified diet), high-fat diet (40 kcal% fat), and high-fat diet +0.02% (w/w) ILG for 16 weeks. Supplementation of ILG resulted in decreased body fat mass and plasma cholesterol level. ILG ameliorated hepatic steatosis by suppressing the expression of hepatic lipogenesis genes and hepatic triglyceride and fatty acid contents, while enhancing β-oxidation in the liver. ILG improved insulin resistance by lowering plasma glucose and insulin levels. This was also demonstrated by the intraperitoneal glucose tolerance test (IPGTT). Additionally, ILG upregulated the expression of insulin signaling-related genes in the liver and muscle. Interestingly, ILG elevated energy expenditure by increasing the expression of thermogenesis genes, which is linked to stimulated mitochondrial biogenesis and uncoupled cellular respiration in brown adipose tissue. ILG also suppressed proinflammatory cytokine levels in the plasma. These results suggest that ILG supplemented at 0.02% in the diet can ameliorate body fat mass, plasma cholesterol, non-alcoholic fatty liver disease, and insulin resistance; these effects were partly mediated by increasing energy expenditure in high-fat fed mice.

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Herring Milt and Herring Milt Protein Hydrolysate Reduce Weight Gain and Improve Insulin Sensitivity and Pancreatic Beta-Cell Function in Diet-Induced Obese Mice

Current Developments in Nutrition ◽

10.1093/cdn/nzaa063_097 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 1699-1699

Author(s):

Yanwen Wang ◽

Sandhya Nair ◽

Jacques Gagnon

Keyword(s):

Insulin Resistance ◽

High Fat Diet ◽

Cell Function ◽

Protein Hydrolysate ◽

Oral Glucose ◽

High Fat ◽

Low Fat ◽

Insulin Resistant ◽

Low Fat Diet ◽

Dietary Casein

Abstract Objectives The present study was designed to examine the effect of herring milt dry powder (HMDP) on glucose homeostasis and related metabolic phenotypes and compare its efficacy with herring milt protein hydrolysate (HMPH) in diet-induced obese and insulin resistant mice. Methods Male C57BL/6 J mice were pretreated with a high-fat diet for 7 weeks were divided into 3 groups where one group continued on the high-fat diet and used as the obese and insulin resistant control (HFC) and the other two groups were fed a modified HFC diet where 70% of casein was replaced with an equal percentage of protein derived from HMDP or HMPH. A group of mice fed a low-fat diet all the time was used as the normal or low-fat control (LFC). Body weight was obtained weekly and food intake was recorded daily. Semi-fating (4–6 hr) blood glucose was measured every other week using a glucometer using the blood from tail vein. Oral glucose tolerance was measured twice during weeks 5 and 9, respectively, and insulin tolerance was determined during week 7 of the treatment. At the end of the experiment, serum was obtained following overnight fasting for the measurement of fasting insulin, leptin, free fatty acids and lipids as well as other glucose metabolism-related biomarkers. Results During the 9-week treatment period, mice on the high-fat diet maintained significantly higher body weight and semi-fasting blood glucose levels and exhibited impaired oral glucose tolerance and insulin resistance relative to mice on the low-fat diet. At the end of the study, the analysis of fasting blood samples revealed that mice on the high-fat diet had increases in serum insulin, leptin, free fatty acids and cholesterol levels. Mice fed the high-fat diet also showed an increase in insulin resistance index and a decrease in β-cell function index. Compared to mice on the high-fat diet, the 70% replacement of dietary casein with an equal percentage of protein derived from HMDP or HMPH reversed or markedly improved these parameters, and HMDP and HMPH showed similar effects. Conclusions The results demonstrate that replacing dietary casein with the same amount of protein derived from either HMDP or HMPH prevents and improves high-fat-diet-induced obesity and insulin resistance. Funding Sources Atlantic Canada Opportunity Agency through the Atlantic Innovation Fund grant (no. 193,594) and National Research Council of Canada – NHP program.

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Effects of three different conjugated linoleic acid preparations on insulin signalling, fat oxidation and mitochondrial function in rats fed a high-fat diet

British Journal Of Nutrition ◽

10.1017/s000711450770497x ◽

2007 ◽

Vol 98 (2) ◽

pp. 264-275 ◽

Cited By ~ 35

Author(s):

Joo Sun Choi ◽

In-Uk Koh ◽

Myeong Ho Jung ◽

Jihyun Song

Keyword(s):

Insulin Resistance ◽

Fatty Acid ◽

Linoleic Acid ◽

Mitochondrial Function ◽

High Fat Diet ◽

Insulin Signalling ◽

Fat Oxidation ◽

Acid Oxidation ◽

High Fat ◽

Cla Isomers

To investigate the effects of three different conjugated linoleic acid (CLA) preparations containing different ratios of CLA isomers on insulin signalling, fatty acid oxidation and mitochondrial function, Sprague–Dawley rats were fed a high-fat diet either unsupplemented or supplemented with one of three CLA preparations at 1 % of the diet for 8 weeks. The first CLA preparation contained approximately 30 % cis-9, trans-11 (c9, t11)-CLA isomer and 40 % trans-10, cis-12 (t10, c12)-CLA isomer (CLA-mix). The other two preparations were an 80:20 mix (c9, t11-CLA-mix) or a 10:90 mix of two CLA isomers (t10, c12-CLA-mix). Insulin resistance was decreased in all three supplemented groups based on the results of homeostasis model assessment and the revised quantitative insulin-sensitivity check index. The phosphorylation of insulin receptor substrate-1 on serine decreased in the livers of all three supplemented groups, while subsequent Akt phosphorylation increased only in the t10, c12-CLA-mix group. Both the c9, t11-CLA-mix and the t10, c12-CLA-mix increased the expression of hepatic adiponectin receptors R1 and 2, which are thought to enhance insulin sensitivity and fat oxidation. The c9, t11-CLA-mix increased protein and mRNA levels of PPARα, acyl-CoA oxidase and uncoupling protein, which are involved in fatty acid oxidation and energy dissipation. The c9, t11-CLA-mix enhanced mitochondrial function and protection against oxidative stress by increasing the activities of cytochrome c oxidase, manganese-superoxide dismutase, glutathione peroxidase, and glutathione reductase and the level of GSH. In conclusion, all three CLA preparations reduced insulin resistance. Among them, the c9, t11-CLA-mix was the most effective based on the parameters reflecting insulin resistance and fat oxidation, and mitochondrial antioxidative enzyme activity in the liver.

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