Carboxymethyl cyclosophoraoses as a flexible pH-responsive solubilizer for pindolol

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2017-2018

This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2018. Also included are papers that describe methods appropriate to glycan and glycoprotein analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, new methods, matrices, derivatization, MALDI imaging, fragmentation and the use of arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Most of the applications are presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and highlights the impact that MALDI imaging is having across a range of diciplines. MALDI is still an ideal technique for carbohydrate analysis and advancements in the technique and the range of applications continue steady progress.

Cyclic β-(1, 2)-glucan blended poly DL lactic co glycolic acid (PLGA 10:90) nanoparticles for drug delivery

Our group had previously reported the encapsulation efficiency of cyclic β-(1, 2)-glucan for various drugs. The current study is aimed at evaluating the use of glucan as a drug carrier system by blending with poly lactic-co- glycolic acid (L:G = 10:90). Nanoparticles of glucan (0.5, 5, 10 and 20 wt %) blended with PLGA and gentamicin were synthesized. Encapsulation efficiency was higher for the blends (93% with 20 wt % of glucan) than the PLGA alone (79.8%). The presence of glucan enhanced both the biodegradability, and biocompatibility of PLGA. Degradation of the nanoparticles in vitro, was autocatalytic with an initial burst release of active drug and the release profile was modeled using the Korsmeyer-Peppas scheme. In vivo studies indicated that the drug released from the blends had high volume of distribution, and greater clearance from the system. Pharmacokinetics of the drug was predicted using a double exponential decay model. Blending with PLGA improved the drug release characteristics of the cyclic β-(1, 2)-glucan.

The behaviour of some antihypertension drugs on human serum paraoxonase-1: an important protector enzyme against atherosclerosis

Objectives

Paraoxonase-1 (PON1) enzyme is related to high-density lipoprotein (HDL), which is calcium dependent. It has essential roles such as protecting LDL against oxidation and detoxification of highly toxic substances. It is a significant risk to reduce the levels of this enzyme in patients with diabetes mellitus, cardiovascular diseases, hyperthyroidism and chronic renal failure.

Methods

Here, it was reported that the purification of human serum PON1 using straightforward methods and determination of the interactions between some antihypertension drugs and the enzyme.

Key finding

It was found that these drugs exhibit potential inhibitor properties for human serum PON1 with IC50 values in the range of 131.40–369.40 μm and Ki values in the range of 56.24 ± 6.75–286.74 ± 28.28 μm. These drugs showed different inhibition mechanisms. It was determined that midodrine and nadolol were exhibited competitive inhibition, but atenolol and pindolol were exhibited non-competitive inhibition.

Conclusion

Usage of these drugs would be hazardous in some cases.

Biotinylated Cyclooligosaccharides for Paclitaxel Solubilization

The poor water solubility of paclitaxel causes significant problems in producing cancer therapeutic formulations. Here, we aimed to solubilize paclitaxel using biocompatible cyclic carbohydrates. Generally recognized as safe, labeled β-cyclodextrin (β-CD), a cyclic α-1,4-glucan consisting of seven glucoses, was prepared, and bio-sourced cyclosophoraoses (CyS), which are unbranched cyclic β-1,2-glucans with 17-23 glucose units, were purified using various chromatographic methods from Rhizobium leguminosarum cultural broth. For effective targeting, CyS and β-CD were modified with a biotinyl moiety in a reaction of mono-6-amino CyS and mono-6-amino-β-CD with N-hydroxysuccinimide ester of biotinamidohexanoic acid. Interestingly, the aqueous solubility of paclitaxel was enhanced 10.3- and 3.7-fold in the presence of biotinyl CyS and biotinyl β-CD, respectively. These findings suggest that biotin-appended cyclooligosaccharides can be applied to improve the delivery of paclitaxel.