Uptake of long chain fatty acids is regulated by dynamic interaction of FAT/CD36 with cholesterol/sphingolipid enriched microdomains (lipid rafts)

Background  

Mechanisms of long chain fatty acid uptake across the plasma membrane are important targets in treatment of many human diseases like obesity or hepatic steatosis. Long chain fatty acid translocation is achieved by a concert of co-existing mechanisms. These lipids can passively diffuse, but certain membrane proteins can also accelerate the transport. However, we now can provide further evidence that not only proteins but also lipid microdomains play an important part in the regulation of the facilitated uptake process.     

The effects of nutritional polyunsaturated fatty acids on locomotor activity in spontaneously hypertensive rats

The present study investigated the effects of nutritional omega-3 polyunsaturated fatty acids on locomotor activity in spontaneously hypertensive rats (SHRs), which are used as an animal model of attention-deficit/hyperactivity disorder (ADHD). For 6 weeks, two groups of randomly assigned SHRs received food either enriched with or deficient in omega-3 fatty acids (based on the American Institute of Nutrition—93 G/AIN93G). Using an open field, locomotor activity was subsequently assessed for 6 days. A marked difference in locomotor activity as assessed by the distance travelled in the open field was found between the two groups of rats. In comparison with rats fed with omega-3 fatty acid-enriched food, the animals on the omega-3 fatty acid-deficient diet showed a significantly higher locomotor activity. The present findings demonstrated that nutritional enrichment with omega-3 fatty acids was associated with reduced motor activity in an established animal model of ADHD and support the notion that omega-3 polyunsaturated fatty acids may play a role in the pathophysiology of ADHD.     

Enzyme-Complemented Activatorsorbent Assay (ECASA): Genetic Engineering for Enzyme-Linked Immunosorbent Assay-Type Mercuric Ion Detection

The sensor component of bacterial mercury resistance systems is the metalloregulatory protein MerR, which has nanomolar sensitivity and high selectivity for Hg(II). A fusion protein of MerR and the α-peptide part of β-galactosidase (LacZα) was constructed by fusing the relevant genes. The protein exhibited both MerR functions and α-complementing activity to the inactive LacZΔM15 (M15) protein. The bifunctional character of the appropriate MerR–LacZα-complemented M15 protein (MerR–LacZα:M15 protein complex) was used to develop a Hg(II)-specific enzyme-complemented activatorsorbent assay. Hg(II) was immobilized and presented on a matrix taking advantage of the high affinity of Hg(II) to SH residues. The immobilized Hg(II) could be specifically detected down to the parts-per-billion level by quantifying the β-galactosidase activity of the bound fusion protein complex.     

Synthesis and properties of sulfated alkyl glycosides

Alkyl glycosides were sulfated with sulfur trioxide-pyridine. Dodecyl - and β- -glucopyranoside gave the corresponding 6-sulfates in 75 and 51% yields, respectively. Separation from polysulfated compounds was carried out by reversed-phase HPLC. Tetradecyl β-maltopyranoside (16) gave a 88:12 mixture of 6′- and 6-sulfates. The sulfated compounds were characterized by ¹H-, ¹³C-, and 2-dimensional NMR spectroscopy. Surfactant and thermotropic liquid-crystalline properties of the sugar derivatives were examined. All of the glycosides show smectic phases (S_A), and the clearing points rise by introduction of sulfate groups. Even glycosides having no unprotected hydroxy groups may show S_A-phases when bearing sulfate groups. The mesomorphic properties cannot be explained by formation of distinct aggregates, but rather must be interpreted by an effective intramolecular contrast.