1.Medium-chain fatty acids inhibit mitochondrial metabolism in astrocytes promoting astrocyte-neuron lactate and ketone body shuttle systems.
Thevenet J1, De Marchi U1, Domingo JS1, Christinat N2, Bultot L3, Lefebvre G4, Sakamoto K3, Descombes P4, Masoodi M2, Wiederkehr A5. FASEB J. 2016 Feb 2. pii: fj.201500182. [Epub ahead of print]
Medium-chain triglycerides have been used as part of a ketogenic diet effective in reducing epileptic episodes. The health benefits of the derived medium-chain fatty acids (MCFAs) are thought to result from the stimulation of liver ketogenesis providing fuel for the brain. We tested whether MCFAs have direct effects on energy metabolism in induced pluripotent stem cell-derived human astrocytes and neurons. Using single-cell imaging, we observed an acute pronounced reduction of the mitochondrial electrical potential and a concomitant drop of the NAD(P)H signal in astrocytes, but not in neurons. Despite the observed effects on mitochondrial function, MCFAs did not lower intracellular ATP levels or activate the energy sensor AMP-activated protein kinase. ATP concentrations in astrocytes were unaltered, even when blocking the respiratory chain, suggesting compensation through accelerated glycolysis. The MCFA decanoic acid (300 μM) promoted glycolysis and augmented lactate formation by 49.
2.Isolation and Synthesis of Laxaphycin B-Type Peptides: A Case Study and Clues to Their Biosynthesis.
Bornancin L1, Boyaud F2, Mahiout Z3, Bonnard I4, Mills SC5,6, Banaigs B7,8, Inguimbert N9. Mar Drugs. 2015 Dec 5;13(12):7285-300. doi: 10.3390/md13127065.
The laxaphyci's B family constitutes a group of five related cyclic lipopeptides isolated from diverse cyanobacteria from all around the world. This group shares a typical structure of 12 amino acids from the l and d series, some of them hydroxylated at the beta position, and all containing a rare beta-amino decanoic acid. Nevertheless, they can be differentiated due to slight variations in the composition of their amino acids, but the configuration of their alpha carbon remains conserved. Here, we provide the synthesis and characterization of new laxaphycin B-type peptides. In doing so we discuss how the synthesis of laxaphycin B and analogues was developed. We also isolate minor acyclic laxaphycins B, which are considered clues to their biosynthesis.
3.Fluorine-Free Superhydrophobic Coatings with pH-induced Wettability Transition for Controllable Oil-Water Separation.
Xu Z1, Zhao Y1, Wang H1, Zhou H1, Qin C1,2, Wang X1, Lin T1. ACS Appl Mater Interfaces. 2016 Mar 2;8(8):5661-7. doi: 10.1021/acsami.5b11720. Epub 2016 Feb 16.
We present a simple, environmentally friendly approach to fabricating superhydrophobic coatings with pH-induced wettability transition. The coatings are prepared from a mixture of silica nanoparticles and decanoic acid-modified TiO2. When the coating is applied on cotton fabric, the fabric turns superhydrophobic in air but superoleophilic in neutral aqueous environment. It is permeable to oil fluids but impermeable to water. However, when the coated fabric is placed in basic aqueous solution or ammonia vapor, it turns hydrophilic but underwater superoleophobic, thus allowing water to penetrate through but blocking oil. Therefore, such a unique, selective water/oil permeation feature makes the treated fabric have capability to separate either oil or water from a water-oil mixture. It may be useful for development of smart oil-water separators, microfluidic valves, and lab-on-a-chip devices.
4.Data on synthesis of oligomeric and polymeric poly(butylene adipate-co-butylene terephthalate) model substrates for the investigation of enzymatic hydrolysis.
Perz V1, Bleymaier K2, Sinkel C3, Kueper U3, Bonnekessel M3, Ribitsch D4, Guebitz GM4. Data Brief. 2016 Feb 19;7:291-8. doi: 10.1016/j.dib.2016.02.029. eCollection 2016.
The aliphatic-aromatic copolyester poly(butylene adipate-co-butylene terephthalate) (PBAT), also known as ecoflex, contains adipic acid, 1,4-butanediol and terephthalic acid and is proven to be compostable , , ). We describe here data for the synthesis and analysis of poly(butylene adipate-co-butylene terephthalate variants with different adipic acid:terephatalic acid ratios and 6 oligomeric PBAT model substrates. Data for the synthesis of the following oligomeric model substrates are described: mono(4-hydroxybutyl) terephthalate (BTa), bis(4-(hexanoyloxy)butyl) terephthalate (HaBTaBHa), bis(4-(decanoyloxy)butyl) terephthalate (DaBTaBDa), bis(4-(tetradecanoyloxy)butyl) terephthalate (TdaBTaBTda), bis(4-hydroxyhexyl) terephthalate (HTaH) and bis(4-(benzoyloxy)butyl) terephthalate (BaBTaBBa). Polymeric PBAT variants were synthesized with adipic acid:terephatalic acid ratios of 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50. These polymeric and oligomeric substances were used as ecoflex model substrates in enzymatic hydrolysis experiments in the article "Substrate specificities of cutinases on aliphatic-aromatic polyesters and on their model substrates" .