Teratogenic Actions of Thermally-stressed Culinary Oils in Rats

Abstract

Lipid oxidation products (LOPs), generated in culinary oils during episodes of thermal stressing can give rise to cellular damage. The aims of this study were to determine whether orally-administered, LOP-containing thermally-stressed safflower oil exerts teratogenic actions in rats, and whether this effect could be prevented by co-administration of alpha-tocopherol (alpha-TOH). Safflower oil was heated for a period of 20 min according to standard frying practices and stored at -20 degrees C under N2. Four experimental groups of pregnant Wistar rats were employed; two received 0.30 ml of pre-heated oil (HO), one of which was also supplemented with 150 mg of alpha-TOH (HOE), and two served as controls, one treated with the non-heated oil (O) and the other without any treatment (C). The oil was administered daily by gavage from day 1 of pregnancy to day 11.5, when the animals were killed and the embryos examined. LOPs and alpha-TOH were determined both in the heated and non-heated oils. The percentage of embryo malformations and reabsorptions were determined in the above four experimental groups. Heating the oil substantially increased its concentration of LOPs and decreased its alpha-TOH content. The percentage of embryo malformations in the HO group was 21.73%, compared with 5.6 and 7% in the O and C groups, respectively. Supplementation of the pre-heated oil with alpha-TOH was found to decrease the percentage of malformations to 7%. The results obtained from these investigations indicate that LOPs detectable at millimolar levels in the heated cooking oils administered (e.g. saturated and alpha,beta-unsaturated aldehydes, and/or their conjugated hydroperoxydiene precursors) exert potent teratogenic actions in experimental animals which are at least partially circumventable by co-administration of the chain-breaking antioxidant alpha-TOH. Plausible mechanisms for these processes and their health relevance to humans regarding diet and methods of frying/cooking are discussed.

Changes in plasma lipids and increased low-density lipoprotein susceptibility to oxidation in pregnancies complicated by gestational diabetes: consequences of obesity

“…It is attractive to speculate that increased LDL oxidation and the lipid peroxides generated during this process may play a role in the congenital malformations associated with GDM and obesity. In the experimental animal model, the oral administration of lipid peroxides generated from heated culinary oils increases the rate of congenital malformations [36]. Further studies need to be made to show the possible relationship between increased LDL susceptibility to oxidation and the higher incidence of congenital anomalies observed in GDM pregnancies.…”

Toxic Oxygenated α,β-Unsaturated Aldehydes and their Study in Foods: A Review

“…In addition, the absorption of these toxic compounds from the diet has been proved and confirmed in experiments with animals (Tinsley et al, 1981;Kanazawa et al, 1985;Kanazawa and Ashida, 1985;Grootveld et al, 1998;Kim et al, 1999;Jenkinson et al, 1999;Indart et al, 2002).…”

“…The obtained results are given in Table 1, and it can be observed that the content of 4-hydroxy-trans-2-nonenal was of the same order in the oil before and after frying and also in the oil retained by the potatoes, the high concentration reached being noteworthy (near 60 mg of 4-hydroxy-trans-2-nonenal per Kg of oil). Due to the fact that this compound can be absorbed from the diet (Kanazawa et al, 1985;Grootveld et al, 1998;Indart et al, 2002) the potential high content in oils rich in linoleic acyl groups submitted to repeated frying episodes should be considered as a subject of health concern.…”

Formation of hydroperoxy‐ and hydroxyalkenals during thermal oxidative degradation of sesame oil monitored by proton NMR

“…In this paper, it has been shown that these toxic compounds can also be produced in foods rich in linoleic acyl groups submitted to the thermal oxidative conditions used in this study. This fact is very important because some authors have pointed out that these oxygenated aldehydes are readily absorbed from the diet [39][40][41], which has been confirmed in experiments with animals [42][43][44].…”