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Papers by Jan Glatz

Journal of lipid …, 2009

The Journal of Lipid Research Skip to main page content. ...

American Journal of …, 2002

It is well known that muscle contraction and insulin can independently translocate GLUT-4 from an... more It is well known that muscle contraction and insulin can independently translocate GLUT-4 from an intracellular depot to the plasma membrane. Recently, we have shown that the fatty acid transporter FAT/CD36 is translocated from an intracellular depot to the plasma membrane by muscle ...

AJP: Endocrinology and Metabolism, 2009

Intramuscular triacylglycerol (IMTG) accumulation in obesity has been attributed to increased fat... more Intramuscular triacylglycerol (IMTG) accumulation in obesity has been attributed to increased fatty acid transport and/or to alterations in mitochondrial fatty acid oxidation. Alternatively, an imbalance in these two processes may channel fatty acids into storage. Therefore, in red and white muscles of lean and obese Zucker rats, we examined whether the increase in IMTG accumulation was attributable to an increased rate of fatty acid transport rather than alterations in subsarcolemmal (SS) or intermyofibrillar (IMF) mitochondrial fatty acid oxidation. In obese animals selected parameters were upregulated, including palmitate transport (red: +100%; white: +51%), plasmalemmal FAT/CD36 (red: +116%; white: +115%; not plasmalemmal FABPpm, FATP1, or FATP4), IMTG concentrations (red: ∼2-fold; white: ∼4-fold), and mitochondrial content (red +30%). Selected mitochondrial parameters were also greater in obese animals, namely, palmitate oxidation (SS red: +91%; SS white: +26%; not IMF mitochon...

Physiology, 2007

Physiology Physiology Skip to main page content. ...

Current Cardiology …, 2008

Long chain fatty acids (LCFAs) provide 70-80% of the energy for cardiac contractile activity. LCF... more Long chain fatty acids (LCFAs) provide 70-80% of the energy for cardiac contractile activity. LCFAs are also essential for many other cellular functions, such as transcriptional regulation of proteins involved in lipid metabolism, modulation of intracellular signalling pathways, and as substrates for membrane constituents. When LCFA uptake exceeds the capacity for their cardiac utilization, the intracellular lipids accumulate and are thought to contribute to contractile dysfunction, arrhythmias, cardiac myocyte apoptosis and congestive heart failure. Moreover, increased cardiac myocyte triacylglycerol, diacylglycerol and ceramide depots are cardinal features associated with obesity and type 2 diabetes. In recent years considerable evidence has accumulated to suggest that, the rate of entry of long chain fatty acids (LCFAs) into the cardiac myocyte is a key factor contributing to a) regulating cardiac LCFA metabolism and b) lipotoxicity in the obese and diabetic heart. In the present review we i) examine the evidence indicating that LCFA transport into the heart involves a protein-mediated mechanism, ii) discuss the proteins involved in this process, including FAT/CD36, FABPpm and FATP1, iii) discuss the mechanisms involved in regulating LCFA transport by some of these proteins (including signaling pathways), as well as iv) the possible interactions of these proteins in regulating LCFA transport into the heart. In addition, v) we discuss how LCFA transport and transporters are altered in the obese/diabetic heart.

The FASEB journal, 2004

We examined whether, in human obesity and type 2 diabetes, long chain fatty acid (LCFA) transport... more We examined whether, in human obesity and type 2 diabetes, long chain fatty acid (LCFA) transport into skeletal muscle is upregulated and contributes to an excess intramuscular triacylglycerol accumulation. In giant sarcolemmal vesicles prepared from human skeletal muscle, LCFA transport rates were upregulated ~4-fold and were associated with an increased intramuscular triacylglycerol content in obese individuals and in type 2 diabetics. In these individuals, the increased sarcolemmal LCFA transport rate was not associated with an altered expression of FAT/CD36 or FABPpm. Instead, the increase in the LCFA transport rate was associated with an increase in sarcolemmal FAT/CD36 but not sarcolemmal FABPpm. Rates of fatty acid esterification were increased threefold in isolated human muscle strips obtained from obese subjects, while concomitantly rates of fatty acid oxidation were not altered. Thus, the increased rate of fatty acid transport may contribute to the increased rates of triacylglycerol accumulation in human skeletal muscle. The altered FAT/CD36 trafficking in muscle from obese subjects and type 2 diabetics juxtaposes the known alterations in GLUT4 trafficking, i.e., GLUT4 is known to be retained in its intracellular depots while FAT/CD36 is retained at the sarcolemma. This redistribution of FAT/CD36 to the sarcolemma may contribute to the etiology of insulin resistance in human muscle, and hence, FAT/CD36 provides another potential therapeutic target for the prevention and/or treatment of insulin resistance.

AJP: Endocrinology and Metabolism, 2007

We examined, in muscle of lean and obese Zucker rats, basal, insulin-induced, and contraction-ind... more We examined, in muscle of lean and obese Zucker rats, basal, insulin-induced, and contraction-induced fatty acid transporter translocation and fatty acid uptake, esterification, and oxidation. In lean rats, insulin and contraction induced the translocation of the fatty acid transporter FAT/CD36 (43 and 41%, respectively) and plasma membrane-associated fatty acid binding protein (FABPpm; 19 and 60%) and increased fatty acid uptake (63 and 40%, respectively). Insulin and contraction increased lean muscle palmitate esterification and oxidation 72 and 61%, respectively. In obese rat muscle, basal levels of sarcolemmal FAT/CD36 (+33%) and FABPpm (+14%) and fatty acid uptake (+30%) and esterification (+32%) were increased, whereas fatty acid oxidation was reduced (−28%). Insulin stimulation of obese rat muscle increased plasmalemmal FABPpm (+15%) but not plasmalemmal FAT/CD36, blunted fatty acid uptake and esterification, and failed to reduce fatty acid oxidation. In contracting obese rat...

Journal of Biological Chemistry, 2011

Cardiology and Cardiovascular Medicine

Journal of Cardiology and Cardiovascular Sciences

Biochimica and Biophysica Acta Molecular and Cell Biology of Lipids, 2009

Obesity (Silver Spring, Md.), 2015

Parental high-fat feeding was proposed to negatively impact metabolic health in offspring. Here, ... more Parental high-fat feeding was proposed to negatively impact metabolic health in offspring. Here, the ectopic fat storage in heart and liver in offspring was investigated, and the effects on mitochondrial function, de novo lipogenesis, and postprandial lipid metabolism were explored in detail. Male and female mice received either a high-fat (HF) or standard chow (LF) diet during mating, gestation and lactation. All offspring animals received the HF diet. Abdominal visceral adipose tissue tended to be higher in HF/HF mice. Cardiac lipid content was also higher in the HF/HF mice (LF/HF vs. 1.03% ± 0.08% vs. 1.33% ± 0.07% of water signal, P = 0.01). In contrast, hepatic lipid content tended to be lower in HF/HF mice compared to LF/HF mice. A severely disturbed postprandial lipid clearance was revealed in HF/HF mice by the results from the triglyceride (TG) tolerance tests (LF/HF vs. 6,753 ± 2,213 vs. 14,367 ± 1,978 mmol l(-1) min(-1) , P = 0.01) and (13) C-fatty acid retention test (LF...

Prostaglandins Leukotrienes and Essential Fatty Acids

Acta anaesthesiologica Scandinavica. Supplementum

Circulation Research, 2015