Distribution of polyunsaturated fatty acids including conjugated linoleic acids in total and subcellular fractions from healthy and cancerous parts of human kidneys

Abstract

Differences in the FA composition of subcellular fractions from healthy and cancerous kidney tissues from the same patients were examined. Only minor differences in CLA content were found between the healthy and the cancerous tissue portions. Regarding the distribution pattern, CLA incorporation into nuclei and cytosol was significantly higher than incorporation into plasma membranes and mitochondria, which could be correlated to the neutral lipid content of these fractions. The subcellular distribution pattern of CLA was similar to that observed with monounsaturated FA but unlike that found with 18:2n-6, which underlines the different physiological properties of CLA and 18:2n-6. Because PUFA have been suggested to have an effect on cancer risk, the contents of n-3 and n-6 PUFA were determined in kidney and renal cell carcinoma (RCC). The 18:2n-6 content and delta5 desaturase activity were significantly lower, and the 18:3n-6, 20:3n-6, and 20:5n-3 contents and delta6 desaturase activity were significantly higher in RCC than in healthy renal tissue, indicating a changed PUFA metabolism in RCC. Previous research has suggested that CLA inhibits the elongation and desaturation of 18:2n-6 into 20:4n-6. In that case, one might speculate that a diet enriched in CLA would be a useful tool in preventing RCC. However, the involvement of CLA in preventing renal cancer could not be demonstrated definitively from the design of this experiment. Further understanding of the cause and/or consequence of the difference in FA metabolism may lead to a better understanding of RCC.

Distribution of conjugated linoleic acid in total and subcellular fractions from normal and cancerous parts of human testes

“…This result is in agreement with our study of CLA in subcellular fractions of normal renal tissue and RCC where it was shown that CLA is best incorporated into nuclei and cytosol and significantly less into plasma membranes and mitochondria [21].…”

“…In contrast to TC, the total CLA content in RCC was found to be significantly increased in the plasma membrane fraction in comparison to the plasma membrane fraction of normal renal tissue [21], whereas no significant differences in the mitochondrial fractions of these two types of tissues were detectable.…”

“…Corresponding to the examination of the normal and cancerous renal tissues [21] it turned out that CLA and MUFA are similarly distributed, whereas 18 : 2n-6 shows a different distribution pattern. The most prominent CLA isomers in testicular tissue and TC are the cis,trans-and trans,cis-isomers, respectively.…”

“…They both examined the CLA content of breast adipose tissue, but none of them determined the CLA content of carcinomas. In an earlier study [21], we compared the CLA content of kidney and renal cell carcinoma (RCC). No significant difference in total CLA content between renal tissue and RCC could be observed.…”

Feeding long-chain n−3 polyunsaturated fatty acids during gestation increases intestinal glucose absorption potentially via the acute activation of AMPK

“…This subcellular distribution of PUFA has received minimal attention in the literature to date. However, differences in the fatty acid composition of human kidney nuclei, cytosol, plasma membranes and mitochondria subcellular fractions have been shown to vary in conjugated linoleic acid content [12]. Furthermore, rats fed corn oil diets versus fish oil diets had differential subcellular (nuclear matrix vs. membrane) n−3 and n−6 PUFA compositions [13].…”