title: Cis-9, trans-11 and trans-10, cis-12 CLA mixture does not change body composition, induces insulin resistance and increases serum HDL cholesterol level in rats.
abstract: Synthetic supplements of conjugated linoleic acid (CLA) containing 50:50 mixture of cis-9, trans-11 and trans-10, cis-12 CLA isomers have been commercialized in some places for reducing body fat. However the safety of this CLA mixture is controversial and in some countries the CLA usage as food supplement is not authorized. Changes in insulinemic control and serum lipids profile are potential negative effects related to consumption of CLA mixture. The present study aimed to evaluate the effects of a diet containing mixture of cis-9, trans-11 and trans-10, cis-12 CLA on prevention of obesity risk as well as on potential side effects such as insulin resistance and dyslipidemia in Wistar rats. Thirty male Wistar rats were randomly assigned to the following dietary treatments (n=10/group), for 60 days: Normolipidic Control (NC), diet containing 4.0% soybean oil (SO); High Fat-Control (HF-C), diet containing 24.0% SO; High Fat-synthetic CLA (HF-CLA), diet containing 1.5% of an isomeric CLA mixture (Luta-CLA 60) and 22.5% SO. Luta-CLA 60 (BASF) contained nearly 60% of CLA (cis-9, trans-11 and trans-10, cis-12 CLA at 50:50 ratio). The HF-CLA diet contained 0.3% of each CLA isomer. HF-CLA diet had no effect on dietary intake and body composition. HF-CLA-fed rats had lower levels of PPARγ protein in retroperitoneal adipose tissue, hyperinsulinemia compared to HF-C-fed rats, hyperglycemia compared to NC-fed rats while no differences in glycemia were observed between NC and HF-C groups, increased HOMA index and higher levels of serum HDL cholesterol. Thus, feeding rats with a high fat diet containing equal parts of cis-9, trans-11 and trans-10, cis-12 CLA isomers had no effect on body composition and induced insulin resistance. Despite HF-CLA-fed rats had increased serum HDL cholesterol levels, caution should be taken before synthetic supplements containing cis-9, trans-11 and trans-10, cis-12 CLA are recommended as a nutritional strategy for weight management.
authors.affiliation: Department of Biology, Federal University of Juiz de Fora.
authors.forename: Mariana Macedo
authors.initials: MM
authors.lastname: de Almeida
authors.forename: Yamara Oliveira
authors.initials: YO
authors.lastname: de Souza
authors.forename: Sheila Cristina Potente
authors.initials: SC
authors.lastname: Dutra Luquetti
authors.forename: Céphora Maria
authors.initials: CM
authors.lastname: Sabarense
authors.forename: José Otávio
authors.initials: JO
authors.lastname: do Amaral Corrêa
authors.forename: Ellen Paula Santos
authors.initials: EP
authors.lastname: da Conceição
authors.forename: Patrícia Cristina
authors.initials: PC
authors.lastname: Lisboa
authors.forename: Egberto Gaspar
authors.initials: EG
authors.lastname: de Moura
authors.forename: Sara Malaguti
authors.initials: SM
authors.lastname: Andrade Soares
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Moura Gualberto
authors.forename: Jacy
authors.initials: J
authors.lastname: Gameiro
authors.forename: Marco Antônio Sundfeld
authors.initials: MA
authors.lastname: da Gama
authors.forename: Fernando César
authors.initials: FC
authors.lastname: Ferraz Lopes
authors.forename: Raúl Marcel
authors.initials: RM
authors.lastname: González Garcia
mesh_terms: D000818:Animals; D001823:Body Composition / Q000187:drug effects*; D008076:Cholesterol, HDL / Q000097:blood*; D019587:Dietary Supplements; D050171:Dyslipidemias; D006943:Hyperglycemia; D006946:Hyperinsulinism; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000378:metabolism; D007536:Isomerism; D044243:Linoleic Acids, Conjugated / Q000009:adverse effects* / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D009765:Obesity / Q000517:prevention & control; D047495:PPAR gamma / Q000378:metabolism; D017208:Rats, Wistar
chemical_list: D008076:Cholesterol, HDL; D044243:Linoleic Acids, Conjugated; D047495:PPAR gamma