Tehran University Medical Journal

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Background: The intestinal absorption of fatty acids may take place through simple diffusion as well as through protein carrier mediated transport, although the relative importance of each pathway is dependent on the ambient condition of entrocytes. Cad-mium ion influences the absorption of fatty acids in entrocytes. However, the effect of cadmium ion on the absorption of fatty acids in different pH values has not been evalu-ated yet. Especially, the luminal pH of small intestine has an essential role in the ab-sorption of fatty acids. In the present study we aimed to evaluate reciprocal effects of cadmium ion and pH of intestine lumen on the absorption of fatty acids in rat model. Methods: In this experimental research, 3 months old Wistar rats (45 rats) were used for experiments. After killing the rats, their intestine was removed and the duodenum and jejunum segments were dissected. Everted Gut Sacs (EGS) were prepared from these duodenum and jejunum segments. The sacs were filled with buffer solution and incubated in a medium containing an appropriate concentration of oleic acid. Then the amounts of oleic acid that had been absorbed into the EGSs in the presence and absence of cadmium ions under different conditions of pH, was measured. Results: Findings of the study demonstrated that the luminal pH of small intestine was effective on the oleic acid uptake and the inhibitory effect of cadmium ions on the up-take of the acid was influenced by pH condition, so that this inhibitory effect was 32% and 36% at the alkaline pHs 7.5 and 9.2, respectively (P< 0.05). At the acidic pHs, 2.5 and 4.5, the inhibitory effect reduced to 11% and 5%, respectively (P< 0.05). Conclusion: Cadmium ion decreased fatty acid uptake by small intestine in rats, and the acidic pH of intestine lumen could attenuate the inhibitory effect of cadmium ion.

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Background: Low density lipoprotein (LDL) particles have shown to be heterogeneous structures with distinctive electrical charges. Alteration in the fatty acids content of the LDL particles is known to affect their structural features, electrical charges, and ultimately physiologic properties and, in this way, may play a role in the pathology of coronary artery disease (CAD). On the basis of evidences, in the present study, the relationship of fatty acids content of LDL particles and their electrical charge was assessed in patients with CAD in comparison with control subjects. Methods: In the current case- control study, from subjects who referred to the Mostafa Khomeini Hospital in Ilam during a time period from December 2013 to October 2014, 40 CAD patients and 40 control subjects were selected based on the clinical and angiographic parameters. The fatty acids content and electrical charges of LDL particles were measured by using a gas chromatography system, equipped with a flame ionization detector GC-FID, Acme 6000 M (Young Lin Co., Korea) as well as a Zetasizer (Malvern Instruments Ltd., UK), respectively. Results: In the present study, CAD patients and control subjects were matched for age, sex, and body mass index (BMI). The electrical charge amounts of LDL particles in the patients group was significantly lower than those in the control subjects (P= 0.0001). There was an inverse correlation between the electrical charge amounts of the LDL particles and the saturated fatty acids as well as linoleic acid contents of them in CAD patients group. However, we found a direct correlation between the unsaturated fatty acids (monounsaturated fatty acids and some of the polyunsaturated ones) content of the LDL particles and their electrical charge amounts (P= 0.02). Conclusion: Results of the present study demonstrated that the increased saturated fatty acids as well as the linoleic acid contents of the LDL particles are associated with decreased electrical charge amounts of these particles and this situation may engage in pathogenesis of CAD.