The renal phospholipid composition of choline-deficient rats

Short-term menhaden oil rich diet changes renal lipid profile in acute kidney injury

Weanling male Wistar rats fed a choline-deficient diet develop acute kidney injury. Menhaden oil, which is a very important source of omega-3 fatty acids, has a notorious protective effect. The mechanism of this protection is unknown; one possibility could be that menhaden oil changes renal lipid profile, with an impact on the functions of biological membranes. The aim of this work was to study the renal lipid profile in rats fed a choline-deficient diet with menhaden oil or vegetable oil as lipids. Rats were divided into 4 groups and fed four different diets for 7 days: choline-deficient or choline-supplemented diets with corn and hydrogenated oils or menhaden oil. Serum homocysteine, vitamin B12, and folic acid were analyzed. Renal lipid profile, as well as the fatty acid composition of the three oils, was measured. Choline-deficient rats fed vegetable oils showed renal cortical necrosis. Renal omega-6 fatty acids were higher in rats fed a cholinedeficient diet and a choline-supplemented diet with vegetable oils, while renal omega-3 fatty acids were higher in rats fed a choline-deficient diet and a choline-supplemented diet with menhaden oil. Rats fed menhaden oil diets had higher levels of renal eicosapentaenoic and docosahexaenoic acids. Renal myristic acid was increased in rats fed menhaden oil. The lipid renal profile varied quickly according to the type of oil present in the diet.

Molecular pathology of acute kidney injury in a choline-deficient model and fish oil protective effect

PURPOSE

The aim of this work was to investigate the potential protective effects of fish oil on the basis of kidney transcriptomic data on a nutritional experimental model.

METHODS

Male weanling Wistar rats were divided into four groups and fed choline-deficient (CD) and choline-supplemented (CS) diets with vegetable oil (VO) and menhaden oil (MO): CSVO, CDVO, CSMO and CDMO. Animals were killed after receiving the diets for 6 days. Total RNA was purified from the right kidney and hybridized to Affymetrix GeneChip Rat Gene 1.0 ST Array. Differentially expressed genes were analyzed.

RESULTS

All CSVO, CSMO and CDMO rats showed no renal alterations, while all CDVO rats showed renal cortical necrosis. A thorough analysis of the differential expression between groups CSMO and CDMO was carried out. There were no differential genes for p < 0.01. The analysis of the differential expression between groups CSVO and CSMO revealed 32 genes, 11 were over-expressed and 21 were under-expressed in CSMO rats.

CONCLUSIONS

This work was part of a large set of experiments and was used in a hypothesis-generating manner. The comprehensive analysis of genetic expression allowed confirming that menhaden oil has a protective effect on this nutritional experimental model and identifying 32 genes that could be responsible for that protection, including Gstp1. These results reveal that gene changes could play a role in renal injury.

Australasian contributions to an understanding of the epidemiology and control of hydatid disease caused by Echinococcus granulosus--past, present and future

For several years after Echinococcus granulosus was introduced into Australasia from Europe, its life cycle was unknown. Before the end of the 19th century, however, Cystic Hydatid Disease (CHD) was recognized in humans as an important cause of death, although its magnitude was not quantified. During the first 50 years of the 20th century, the urban component declined, but CHD remained a serious source of ill-health. During the second half of the 20th century major research contributions have included: (i) differentiation of pastoral from wildlife Echinococcus and (ii) breaking the 'epidemiological code' of the family Taeniidae, thereby defining the conditions under which transmission occurs. Based on this research and concurrent surveys, it is concluded that the present geographical distribution of E. granulosus in domestic animals and CHD in the rural population is determined by climate; being uncommon where hot dry seasons continue beyond a few months. The parasite's range may be extended in its wildlife cycle through a highly susceptible definitive host--the dingo. The ease with which blowflies transfer taeniid eggs from dog faeces to animal and human foodstuffs implies that in Australasia, CHD can sometimes be regarded as foodborne. A perceived decline in autochthonus cases in the rural community during the second half of the 20th century may be accounted for by increased standards of living generated by economic advancement. Where a decline has not occurred or incidence is unusually high, CHD may be acting as an indicator of social disadvantage. Field trials and control programmes demonstrated that pastoral echinococcosis readily responded to intervention. Indeed, in both New Zealand and Tasmania, using different administrative structures and methods of funding, E. granulosus was driven from endemic towards extinction status. The really convincing result was the rapid decline in CHD in all age groups. The problem still to be solved is to identify methods for eliminating foci where high levels of CHD still exist but, continent- or even state-wide intervention may not be considered to be cost-effective using current tools. Here, mathematical modelling and cost-benefit analysis can be regarded as powerful methods to assist the decision-making process.