Metallothioneins 1 and 2, but not 3, are regulated by nutritional status in rat white adipose tissue

The influence of fasting or fasting/refeeding on: MT2 and MT3 mRNA level relative to β-actin expression in WAT of rats. (DOCX 13 kb

Hepatic and serum branched-chain fatty acid profile in patients with nonalcoholic fatty liver disease: A case–control study

Objective Alterations in the hepatic lipidome are a crucial factor involved in the pathophysiology of nonalcoholic fatty liver disease (NAFLD). The aim of this study was to evaluate the serum and hepatic profile of branched-chain fatty acids (BCFAs) in patients with different stages of NAFLD. Methods This was a case–control study performed in 27 patients without NAFLD, 49 patients with nonalcoholic fatty liver, and 17 patients with nonalcoholic steatohepatitis, defined by liver biopsies. Serum and hepatic levels of BCFAs were analyzed by gas chromatography–mass spectrometry. The hepatic expression of genes involved in the endogenous synthesis of BCFAs was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). Results A significant increase in hepatic BCFAs was found in subjects with NAFLD compared with those without NAFLD; no differences were observed in serum BCFAs between study groups. Trimethyl BCFAs, iso-BCFAs, and anteiso-BCFAs were increased in subjects with NAFLD (either nonalcoholic fatty liver or nonalcoholic steatohepatitis) compared with those without NAFLD. Correlation analysis showed a relationship between hepatic BCFAs and the histopathological diagnosis of NAFLD, as well as other histological and biochemical parameters related to this disease. Gene expression analysis in liver showed that the mRNA levels of BCAT1, BCAT2, and BCKDHA were upregulated in patients with NAFLD. Conclusions These results suggest that the increased production of liver BCFAs might be related to NAFLD development and progression.This work was funded by the Institute of Health “Carlos III” (ISCIII) and cofunded by the Fondo Europeo de Desarrollo Regional-FEDER (grant number PI20/00505). J.C.F-G was supported by an intensification research program (INT21/00078, ISCIII, Spain; cofunded by the Fondo Europeo de Desarrollo Regional-FEDER), M.A.M-S was supported by a PFIS predoctoral fellowship from the ISCIII (FI21/00003, ISCIII, Spain; cofunded by the Fondo Europeo de Desarrollo Regional-FEDER), and B.R-M was supported by the “Miguel Servet Type I” program (CP19/00098, ISCIII, Spain; cofunded by the Fondo Europeo de Desarrollo Regional-FEDER). The funding organizations played no role in the design of the study, review and interpretation of the data, or final approval of the manuscript. Funding for open access charge: Universidad de Málaga / CBU

Exercise and Conjugated Linoleic Acid Supplementation Induce Changes in the Composition of Liver Fatty Acids

Exercise and supplementation with conjugated linoleic acid (CLA) are used to reduce body weight and to improve health. Applied together, they may exert a synergistic effect. However, the effects of exercise and CLA supplementation on liver metabolism are poorly understood. The aim of this study was to examine the influence of exercise and CLA supplementation on fatty acids (FA) composition in mouse liver. We analyzed 44 of known FAs of this organ by gas chromatography-mass spectrometry. Our results demonstrated that exercise contributed to a decrease in odd-chain FA and an increase in n-6 polyunsaturated FA contents. In turn, CLA stimulated an increase in branched-chain FAs and n-3 polyunsaturated FAs. Exercise combined with CLA supplementation caused a substantial increase in branched-chain FA content and a slight increase in n-6 polyunsaturated FAs. The elevated liver content of branched-chain FAs after the exercise combined with CLA supplementation, as well as the increase in n-3 polyunsaturated FAs after CLA may be favorable since both these FA groups were previously shown to produce health benefits. However, the expression pattern of enzymes involved in fatty acid synthesis did not match the changes in FA composition. Thus, the mechanism of exercise- and CLA-induced changes in liver FA profile is yet to be established. Also, the consequences of CLA- and/or exercise-induced changes in the composition of liver FAs need to be elucidated

Does antioxidant therapy influence every aspect of quality of life?

To present problems that might severely impact the conclusions drawn by the authors of an article on antioxidant treatment in chronic pancreatitis (World J Gastroenterol 2010; 16: 4066-4071). We analyzed and discussed this paper by Shah et al, and found that promising as it is, this study has some methodological shortcomings, such as: cross-sectional nature of the study, lack of initial evaluations of quality of life and regular follow-ups to determine the dynamics and real directions of changes in quality of life. We therefore concluded that the results of the study by Shah et al are biased and, although very promising, should not be considered as scientifically relevant

Up-Regulation Mttp and Apob Gene Expression in Rat Liver is Related to Post-Lipectomy Hypertriglyceridemia

Background/Aims: The aim of this study was to explain the molecular basis for elevated concentrations of circulating triglycerides (TAGs) after partial surgical removal of adipose tissue (lipectomy) in rats. Methods: The levels of mRNA and protein: a) involved in synthesis of fatty acids and TAGs; b) participating in TAG-rich lipoproteins assembly and secretion; and c) transcription factors essential for maintaining TAG homeostasis were determined by RT-PCR and Western Blot in the livers of control and lipectomized rats. Results: Partial lipectomy was associated with increase: a) in serum and liver concentration of TAGs, and b) in the liver levels of mRNA of microsomal TAG transfer protein (MTP) and apolipoprotein B-100 (ApoB-100). These changes were tightly associated with up-regulation of Hnf1a and Hnf4a gene expression in the liver. Lipectomy was also reflected by a significant increase in the expression of genes encoding: a) fatty acid synthase (FASN), b) glycerol 3-phosphate acyltransferase 1 (GPAT1), diacylglycerol acyltransferases 1 and 2 (DGAT1 and DGAT2), c) spot 14 protein (S14) and SREBP-1 in the liver. Conclusion: Coordinated up-regulation of Mttp, Apob, Hnf1a, Hnf4a, Fasn, Gpam and Dgat (1 and 2) gene expressions may contribute to the increase in circulating and liver concentrations of TAGs after lipectomy in an experimental rat model

Modern Methods of Sample Preparation for the Analysis of Oxylipins in Biological Samples

Oxylipins are potent lipid mediators derived from polyunsaturated fatty acids, which play important roles in various biological processes. Being important regulators and/or markers of a wide range of normal and pathological processes, oxylipins are becoming a popular subject of research; however, the low stability and often very low concentration of oxylipins in samples are a significant challenge for authors and continuous improvement is required in both the extraction and analysis techniques. In recent years, the study of oxylipins has been directly related to the development of new technological platforms based on mass spectrometry (LC−MS/MS and gas chromatography−mass spectrometry (GC−MS)/MS), as well as the improvement in methods for the extraction of oxylipins from biological samples. In this review, we systematize and compare information on sample preparation procedures, including solid-phase extraction, liquid−liquid extraction from different biological tissues

Methods of the Analysis of Oxylipins in Biological Samples

Oxylipins are derivatives of polyunsaturated fatty acids and due to their important and diverse functions in the body, they have become a popular subject of studies. The main challenge for researchers is their low stability and often very low concentration in samples. Therefore, in recent years there have been developments in the extraction and analysis methods of oxylipins. New approaches in extraction methods were described in our previous review. In turn, the old analysis methods have been replaced by new approaches based on mass spectrometry (MS) coupled with liquid chromatography (LC) and gas chromatography (GC), and the best of these methods allow hundreds of oxylipins to be quantitatively identified. This review presents comparative and comprehensive information on the progress of various methods used by various authors to achieve the best results in the analysis of oxylipins in biological samples