β-Aminoisobutyric Acid Induces Browning of White Fat and Hepatic β-Oxidation and Is Inversely Correlated with Cardiometabolic Risk Factors

The transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) regulates metabolic genes in skeletal muscle and contributes to the response of muscle to exercise. Muscle PGC-1α transgenic expression and exercise both increase the expression of thermogenic genes within white adipose. How the PGC-1α-mediated response to exercise in muscle conveys signals to other tissues remains incompletely defined. We employed a metabolomic approach to examine metabolites secreted from myocytes with forced expression of PGC-1α, and identified β-aminoisobutyric acid (BAIBA) as a small molecule myokine. BAIBA increases the expression of brown adipocyte-specific genes in white adipocytes and β-oxidation in hepatocytes both in vitro and in vivo through a PPARα-mediated mechanism, induces a brown adipose-like phenotype in human pluripotent stem cells, and improves glucose homeostasis in mice. In humans, plasma BAIBA concentrations are increased with exercise and inversely associated with metabolic risk factors. BAIBA may thus contribute to exercise-induced protection from metabolic diseases

INTEGRATED PROJECTION FOR RUNOFF CHANGES IN LARGE RUSSIAN RIVER BASINS IN THE XXI CENTURY

The paper discusses an approach to a long-term forecast of river runoff changes for Russian large river basins in the first third of the XXI century caused by climate warming and social-economic changes. The approach considers runoff changes under a range of possible climate warming effects. This range is chosen by generalizing the calculation results obtained by using an ensemble of global climate models within CMIP 3 and CMIP 5 experiments for twocontrasting scenarios (A2/RCP 8.5 and B1/RCP 2.6) of globally averaged air temperature rises. The approach also utilizes a method for alternative scenario for water consumption related to socio-economic changes. The obtained scenario estimates show that expected changes in the Volga and Don annual river runoff and its intra-annual distribution in the first third of this century can be relatively small, while changes in water use characteristics may be extremely negative in some scenarios, especially in the Don River basin

Interaction Between Vitamin E and Polyunsaturated Fatty Acids

Polyunsaturated fatty acids (PUFA) are nutritionally essential since they cannot be synthesized de novo from two-carbon fragments. As a result of their unsaturated double bonds, PUFA are susceptible to chemical reactions with reactive oxygen and nitrogen species (ROS and RNS, respectively). PUFA incorporated into phospholipids and present in biological membranes not only influence membrane fluidity, curvature, and the properties of membrane microdomains, but increase also the risk for chain reactions of lipid peroxidation leading to membrane destabilization and cellular dysfunction. Vitamin E, the main lipid-soluble antioxidant, stabilizes membranes by itself and protects PUFA by scavenging lipid peroxyl radicals. Thus, vitamin E and PUFA form an interdependent chemical pair in which vitamin E protects PUFA, whereas excess PUFA “consume” vitamin E, a high PUFA/vitamin E ratio being generally assumed as disadvantageous. In cells, both PUFA and vitamin E have their own redox-independent regulatory functions, mostly after being metabolized to active lipid mediators able to bind to specific enzymes and receptors involved in modulating specific signal transduction and gene expression pathways. Thus, the efficiency of uptake, transport, and metabolism of vitamin E and PUFA, their interaction, and their consequent relative levels in cells and tissues are important determinants for both physiological and pathophysiological cellular functions and therefore influence the risk for a number of diseases