Absorption, Distribution and Excretion
... The objectives of the study were to 1) use the whole body fatty acid balance method to quantify whole-body concentrations of linoleate in humans, 2) estimate the distribution of linoleate between adipose and lean tissue, and 3) assess the effect of weight loss on linoleate stores and beta-oxidation in obese humans. Nine healthy obese men underwent supervised weight loss for 112 d (16 wk). Magnetic resonance imaging data and fatty acid profiles from fat biopsies were both used to determine linoleate stores in adipose and lean tissue and in the whole body. Linoleate beta-oxidation was calculated as intake - (accumulation + excretion). Mean weight loss was 13 kg and linoleate intake was 24 +/- 6 mmol/d over the study period. Whole-body loss of linoleate was 37 +/- 18 mmol/d, or 28% of the level before weight loss. Combining the intake and whole-body loss of linoleate resulted in linoleate beta-oxidation exceeding intake by 2.5-fold during the weight-loss period. All dietary linoleate is beta-oxidized and at least an equivalent amount of linoleate is lost from the body during moderate weight loss in obese men. The method studied permits the assessment of long-term changes in linoleate homeostasis in obese humans and may be useful in determining the risk of linoleate deficiency in other conditions. /Linoleate/
Human milk fatty acids vary with maternal dietary fat composition. Hydrogenated dietary oils with trans fatty acids may displace cis n-6 and n-3 unsaturated fatty acids or have adverse effects on their metabolism. The effects of milk trans, n-6, and n-3 fatty acids in breast-fed infants are unclear, although n-6 and n-3 fatty acids are important in infant growth and development. /The authors/ sought to determine the relations between trans and cis unsaturated fatty acids in milk and plasma phospholipids and triacylglycerols of breast-fed infants, and to identify the major maternal dietary sources of trans fatty acids. collected milk from 103 mothers with exclusively breast-fed 2-mo-old infants, blood from 62 infants, and 3-d dietary records from 21 mothers. Results: Mean (+/-SEM) percentages of trans fatty acids were as follows: milk, 7.1 +/- 0.32%; infants' triacylglycerols, 6.5 +/- 0.33%; and infants' phospholipids, 3.7 +/- 0.16%. Milk trans fatty acids, a-linolenic acid (18:3n-3), arachidonic acid (20:4n-6), docosahexaenoic acid (22:6n-3) (P < 0.001), and linoleic acid (18:2n-6) (P = 0.007) were each related to the same fatty acid in infant plasma phospholipids. Milk trans fatty acids were inversely related to milk 18:2n-6 and 18:3n-3, but not to milk or infant plasma 20:4n-6 or 22:6n-3. trans Fatty acids represented 7.7% of maternal total fat intake (2.5% of total energy); the major dietary sources were bakery products and breads (32%), snacks (14%), fast foods (11%), and margarines and shortenings (11%). There were comparable concentrations of trans fatty acids in the maternal diet, breast milk, and plasma triacylglycerols of breast-fed infants. Prepared foods were the major dietary source of trans fatty acids.
Some /conjugated linoleic acid/ CLA appears to get incorporated into the phospholipids of cell membranes. /Conjugated linoleic acid/

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Metabolism / Metabolites
/OTHER TOXICITY INFORMATION/ The hepatotoxicity of orally administered secondary autoxidation products of linoleic acid in rats was investigated and compared to the effects following administration of a saline solution and linoleic acid as controls. The de novo synthesis of fatty acids was strongly reduced in the secondary products group. The level of nicotine adenine dinucleotide phosphate (NADPH) in the liver significantly decreased whereas that of nicotine adenine dinucleotide (NADH) did not. The activities of glucose 6-phosphate dehydrogenase and phosphogluconate dehydrogenase apparently decreased. The activities of NAD + kinase and NAD + synthetase decreased and that of NAD + nucleosidase increased in the secondary products group. Therefore the depletion of nicotine adenine dinucleotide phosphate can be attributed to the inhibition of two metabolic systems (a nicotine adenine dinucleotide phosphate-supplemental system and a synthetic system of NADP and NAD), and resulted in the reduction of lipogenesis in the liver. /Autooxidation products/
... Linoleic acid stimulated tumor growth because it is converted by hepatoma 7288CTC to the mitogen, 13-hydroxyoctadecadienoic acid (13-HODE). ...
13-hydroxyoctadecadienoic acid (13-HODE) synthesis is enhanced by cyclic AMP. Gamma-linolenic acid, a desaturated metabolite of linoleic acid, causes substantial stimulation of 13-HODE synthesis. A fall in gamma-linolenic acid synthesis with age may be related to the age-related fall in 13-HODE formation. /gamma-Linolenic acid/
Linoleic acid has known human metabolites that include Leukotoxin and Isoleukotoxin.

Linoleic acid is a colorless to straw colored liquid. A polyunsaturated fatty acid essential to human diet.
Linoleic acid is an octadecadienoic acid in which the two double bonds are at positions 9 and 12 and have Z (cis) stereochemistry. It has a role as a plant metabolite, a Daphnia galeata metabolite and an algal metabolite. It is an omega-6 fatty acid and an octadecadienoic acid. It is a conjugate acid of a linoleate.
Linoleic Acid has been reported in Calodendrum capense, Camellia sinensis, and other organisms with data available.
Linoleic Acid is a polyunsaturated essential fatty acid found mostly in plant oils. It is used in the biosynthesis of prostaglandins and cell membranes.
Linoleic acid is a doubly unsaturated fatty acid, also known as an omega-6 fatty acid, occurring widely in plant glycosides. In this particular polyunsaturated fatty acid (PUFA), the first double bond is located between the sixth and seventh carbon atom from the methyl end of the fatty acid (n-6). Linoleic acid is an essential fatty acid in human nutrition because it cannot be synthesized by humans. It is used in the biosynthesis of prostaglandins (via arachidonic acid) and cell membranes. (From Stedman, 26th ed).
A doubly unsaturated fatty acid, occurring widely in plant glycosides. It is an essential fatty acid in mammalian nutrition and is used in the biosynthesis of prostaglandins and cell membranes. (From Stedman, 26th ed)
See also: Cod Liver Oil (part of); Krill oil (part of); Saw Palmetto (part of) ... View More ...

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Mechanism of Action
/The objective of this work was/ to study the gene expression of the resistin and the effects of conjugated linoleic acid on its expression in white adipose tissue of obese rats fed with high fat diet during the formation of insulin resistance. Male Wistar rats were randomly separated in control group, high-fat group and high fat + conjugated linoleic acid (CLA) group (0.75 g, 1.50 g, 3.00 g per 100 g diet weight), using reverse transcription polymerase chain reaction (RT-PCR) technique to measure the expression level of resistin and peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA expression. The serum insulin and glucose levels of obese rats were (11.11 +/- 2.73) mIU/L, (5.09 +/- 0.66) mmol/L, and supplement of CLA might decrease hyperinsulinemia and hyperglycemia, in CLA group (0.75 g, 1.50 g, 3.00 g per 100 g diet weight) the serum insulin levels were (6.99 +/- 1.77) mIU/L, (7.36 +/- 1.48) mIU/L, (7.85 +/- 1.60) mIU/L, and glucose levels were (4.28 +/- 0.72) mmol/L, (4.18 +/- 0.55) mmol/L, (4.06 +/- 0.63) mmol/L. The expression of resistin in adipose tissue of obese rat fed with high fat diet was increased as compared with those fed with basic diet. CLA might increase the expression of resistin and PPARgamma in adipose tissue of obese rat. The expression of resistin mRNA of obese rat fed with high fat diet was higher than those fed with basic diet, and CLA might improve the insulin resistance in obese rats and possibly upregulate the expression of resistin through activing PPARgamma. /Conjugated linoleic acid/
Conjugated linoleic acid (CLA) is a mixture of positional (e.g. 7,9; 9,11; 10,12; 11,13) and geometric (cis or trans) isomers of octadecadienoic acid. This compound was first shown to prevent mammary carcinogenesis in murine models. Later investigations uncovered a number of additional health benefits, including decreasing atherosclerosis and inflammation while enhancing immune function. The mechanisms of action underlying these biological properties are not clearly understood. The aim of this review is to highlight recent advances in CLA research related to experimental inflammatory bowel disease. In addition, two possible mechanisms of action (i.e. endoplasmic and nuclear) were discussed in detail in the context of enteric inflammatory disorders. Conjugated linoleic acid was first implicated in down-regulating the generation of inducible eicosanoids (i.e. PGE(2) and LTB(4)) involved in early micro-inflammatory events (endoplasmic). More recently, CLA has been shown to modulate the expression of genes regulated by peroxisome proliferator-activated receptors (PPARs; nuclear). In pigs, prolonged dietary CLA treatment stimulated the expression of PPAR-gamma in the muscle. Thus, evidence supporting both mechanistic theories of CLA acting through eicosanoid synthesis and PPAR activity is available. The further understanding of the anti-inflammatory mechanisms of action of CLA may yield novel nutritional therapies for enteric inflammation. /Conjugated linoleic acid/
/Conjugated linoleic acid/ CLA may modulate eicosanoid activity as well as the activity... of tumor necrosis factor-alpha. /Conjugated linoleic acid/

C18H32O2

280.4455

280.24

60-33-3

7049-66-3;30175-49-6;67922-65-0

5280450

Colorless oil
Colorless to straw-colored liquid

0.9±0.1 g/cm3

360.6±0.0 °C at 760 mmHg

-5 °C

273.0±14.4 °C

0.0±1.7 mmHg at 25°C

1.478

7.18

1

2

14

20

267

0

O([H])C(C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])/C(/[H])=C(/[H])\C([H])([H])/C(/[H])=C(/[H])\C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H])=O

OYHQOLUKZRVURQ-HZJYTTRNSA-N

InChI=1S/C18H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20/h6-7,9-10H,2-5,8,11-17H2,1H3,(H,19,20)/b7-6-,10-9-

(9Z,12Z)-octadeca-9,12-dienoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: (1). This product requires protection from light (avoid light exposure) during transportation and storage.  (2). Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)