Altered metabolism of lipids is currently considered a hallmark characteristic of many malignancies, including colorectal cancer (CRC). Lipids are a large group of metabolites that differ in terms of their fatty acid composition. This review summarizes recent evidence, documenting many alterations in the content and composition of fatty acids, polar lipids, oxylipins and triacylglycerols in CRC patients’ sera, tumor tissues and adipose tissue. Some of altered lipid molecules may be potential biomarkers of CRC risk, development and progression. Owing to a significant role of many lipids in cancer cell metabolism, some of lipid metabolism pathways may also constitute specific targets for anti-CRC therapy.

Increased physical activity is an optimal way to maintain a good health. During exercise, triacylglycerols, an energy reservoir in adipose tissue, are hydrolyzed to free fatty acids which are then released to the circulation, providing a fuel for working muscles. Thus, regular physical activity leads to a reduction of adipose tissue mass and improves metabolism. However, the reduction of lipid reservoir is also associated with many other interesting changes in adipose tissue fatty acid metabolism. For example, a prolonged exercise contributes to a decrease in lipoprotein lipase activity and resultant reduction of fatty acid uptake. This results in the improvement of mitochondrial function and upregulation of enzymes involved in the metabolism of polyunsaturated fatty acids. The exercise-induced changes in adipocyte metabolism are associated with modifications of fatty acid composition. The modifications are adipose tissue depot-specific and follow different patterns in visceral and subcutaneous adipose tissue. Moreover, exercise affects adipokine release from adipose tissue, and thus, may mitigate inflammation and improve insulin sensitivity. Another consequence of exercise is the recently described phenomenon of adipose tissue “beiging”, i.e. a switch from energy-storing white adipocyte phenotype to thermogenic fatty acid oxidizing beige adipocytes. This process is regulated by myokines released during the exercise. In this review, we summarize published evidence for the exercise-related changes in fatty acid metabolism and adipokine release in adipose tissue, and their potential contribution to beneficial cardiovascular and metabolic effects of physical activity.

Purpose of Review: The review aims to describe short-chain fatty acids (SCFAs) as metabolites of bacteria, their complex influence on whole-body metabolism, and alterations in the SCFA profile in obesity and after bariatric surgery (BS). Recent Findings: The fecal profile of SCFAs in obese patients differs from that of lean patients, as well as their gut microbiota composition. In obese patients, a lower diversity of bacteria is observed, as well as higher concentrations of SCFAs in stool samples. Obesity is now considered a global epidemic and bariatric surgery (BS) is an effective treatment for severe obesity. BS affects the structure and functioning of the digestive system, and also alters gut microbiota and the concentration of fecal SCFAs. Generally, after BS, SCFA levels are lower but levels of branched short-chain fatty acids (BSCFAs) are elevated, the effect of which is not fully understood. Moreover, changes in the profile of circulating SCFAs are little known and this is an area for further research. Summary: Obesity seems to be inherently associated with changes in the SCFA profile. It is necessary to better understand the impact of BS on microbiota and the metabolome in both feces and blood as only a small percentage of SCFAs are excreted. Further research may allow the development of a personalized therapeutic approach to the BS patient in terms of diet and prebiotic intervention.

Objective: While small amounts of odd‐chain fatty acids (OCFAs) and branched‐chain fatty acids (BCFAs) were known to be present in mammals, it was quite recently that they were shown to play an important role in human health. However, still little is known on OCFA and BCFA profiles in subjects who have obesity. The aim of this study was to verify whether obesity is associated with changes in serum OCFA and BCFA profiles.Methods: Serum content of fatty acids was determined by gas chromatography‐mass spectroscopy in 23 patients with excess weight and 21 nonobese controls.Results: Six OCFAs and six BCFAs (three iso‐BCFAs and three anteiso‐BCFAs) were found in sera from the examined subjects. Patients with excess weight presented with significantly lower serum iso‐BCFA levels than the controls. Total serum content of iso‐BCFAs correlated inversely with serum insulin, triglycerides, and 18:1/18:0 desaturation index. Both OCFA and iso‐BCFA levels correlated inversely with C‐reactive protein concentration.Conclusions: Lower iso‐BCFA content in patients with excess weight may be involved in elevation of serum concentration of triglycerides and inflammation. Decreased contents of iso‐BCFAs in subjects with have obesity, and established anti‐inflammatory, antidiabetic, and anticancer properties of these fatty acids, point to potential beneficial effects of an iso‐BCFA‐rich diet.