1.Acid Ceramidase and the Treatment of Ceramide Diseases: The Expanding Role of Enzyme Replacement Therapy.
Schuchman EH1. Biochim Biophys Acta. 2016 May 4. pii: S0925-4439(16)30094-1. doi: 10.1016/j.bbadis.2016.05.001. [Epub ahead of print]
Ceramides are a diverse group of sphingolipids that play important roles in many biological processes. Acid ceramidase (AC) is one key enzyme that regulates ceramide metabolism. Early research on AC focused on the fact that it is the enzyme deficient in the rare genetic disorder, Farber Lipogranulomatosis. Recent research has revealed that deficiency of the same enzyme is responsible for a rare form of spinal muscular atrophy associated with myoclonic epilepsy (SMA-PME). Due to their diverse role in biology, accumulation of ceramides also has been implicated in the pathobiology of many other common diseases, including infectious lung diseases, diabetes, cancers and others. This has revealed the potential of AC as a therapy for many of these diseases. This review will focus on the biology of AC and the potential role of this enzyme in the treatment of human disease.
2.Temperature-Mediated Variations in Cellular Membrane Fatty Acid Composition of Staphylococcus aureus in Resistance to Pulsed Electric Fields.
Wang LH1, Wang MS1, Zeng XA2, Liu ZW1. Biochim Biophys Acta. 2016 May 4. pii: S0005-2736(16)30145-6. doi: 10.1016/j.bbamem.2016.05.003. [Epub ahead of print]
Effects of growth temperature on cell membrane fatty acid composition, fluidity and lethal and sublethal injury by pulsed electric fields (PEF) in Staphylococcus aureus ATCC 43300 (S. aureus) in the stationary phase were investigated. Analysis of the membrane fatty acids by gas chromatography-mass spectrometry (GC-MS) revealed that branched chain fatty acids (iso C14:0, iso C15:0, anteiso C15:0 and anteiso C17:0) and straight chain fatty acids (C12:0, C14:0, C16:0, C17:0 and C18:0) were primary constituents in the membrane. The S. aureus changed its membrane fatty acid composition and its overall fluidity when exposed to different temperatures. The PEF lethal and sublethal effects were assessed, and results suggested that the degree of inactivation depended on the cell membrane structure, electric field strength and treatment time. The PEF inactivation kinetics including lethal and sublethal injury fractions were fitted with non-linear Weibull distribution, suggesting that inactivation of the first log cycle of S.
3.Minodronic acid ameliorates vertebral bone strength by increasing bone mineral density in 9-month treatment of ovariectomized cynomolgus monkeys.
Tanaka M1, Mori H2, Kawabata K2, Mashiba T3. Bone. 2016 May 4. pii: S8756-3282(16)30128-4. doi: 10.1016/j.bone.2016.05.001. [Epub ahead of print]
The effect of treatment for 9months with minodronic acid, a nitrogen-containing bisphosphonate, on vertebral mechanical strength was examined in ovariectomized (OVX) cynomolgus monkeys. Forty skeletally mature female monkeys were randomized into four OVX groups and one sham group (n=8) based on lumbar bone mineral density (BMD). OVX animals were treated orally with 15 and 150μg/kg QD of minodronic acid or 500μg/kg QD alendronate as a reference drug. Measurements of bone turnover markers and lumbar BMD were conducted at 0, 4 and 8months. Measurements of bone mechanical strength and minodronic acid concentration in vertebral bodies were also performed. OVX resulted in a decrease in lumbar BMD and an increase in bone turnover markers at 4 and 8months, compared to the sham group, and the ultimate load on the lumbar vertebra was decreased in OVX animals. Minodronic acid and alendronate prevented the OVX-induced increase in bone turnover markers and decrease in lumbar BMD.
4.Poly(ε-caprolactone)/triclosan loaded polylactic acid nanoparticles composite: A long-term antibacterial bionanocomposite with sustained release.
Kaffashi B1, Davoodi S2, Oliaei E2. Int J Pharm. 2016 May 4. pii: S0378-5173(16)30376-3. doi: 10.1016/j.ijpharm.2016.05.009. [Epub ahead of print]
In this study, the antibacterial bionanocomposites of poly(ε-caprolactone) (PCL) with different concentrations of triclosan (TC) loaded polylactic acid (PLA) nanoparticles (30wt % triclosan) (LATC30) were fabricated via a melt mixing process in order to lower the burst release of PCL and to extend the antibacterial property during its performance. Due to the PLA's higher glass transition temperature (Tg) and less flexibility compared with PCL; the PLA nanoparticles efficiently trapped the TC particles, reduced the burst release of TC from the bionanocomposites; and extended the antibacterial property of the samples up to two years. The melt mixing temperature was adjusted to a temperature lower than the melting point of LATC30 nanoparticles; therefore, these nanoparticles were dispersed in the PCL matrix without any chemical reaction and/or drug extraction. The sustained release behavior of TC from PCL remained unchanged since no significant changes occurred in the samples' crystallinity compared with that in the neat PCL.