Peptidomimetic ß-Secretase Inhibitors Comprising a Sequence of Amyloid-ß Peptide for Alzheimer's Disease.

Alzheimer's disease is a grave social problem in an aging population. A major problem is the passage of drugs through the blood-brain barrier. This work tests the hypothesis that the conjugation of peptidomimetic ß-secretase inhibitors with a fragment of amyloid-ß peptide facilitates entrance into the central nervous system. HVR-3 (compound 4), one of the conjugation products, was found to be as potent as OM00-3, a known peptidomimetic inhibitor, 4-fold more selective toward ß-secretase 1 in relation to ß-secretase 2 and 3-fold more resistant to in vitro metabolization in human serum. Its intravenous administration to mice and Wistar rats generated an active metabolite recovered from the rodent's brains.

A methodology for detection and quantification of esterase activity.

Carboxylesterases are important enzymes for xenobiotic metabolism and are receiving increasing attention in the context of cancer therapies. Quantification of individual carboxylesterase activity is important since protein levels do not always correlate to activity and significant interorgan, interindividual, and interspecies variations exist. Here we present a methodology enabling the specific quantification of carboxylesterase 2 activity in a pool of other esterases. Method applicability is illustrated for the evaluation of interspecies variation and for activity assessment of transfected cell extracts. The methodology can easily be adapted to the evaluation of other esterases upon careful selection of adequate substrates and/or specific inhibitors.

Carboxylesterase 2 production and characterization in human cells: new insights into enzyme oligomerization and activity.

Carboxylesterase 2 (CES2), the main carboxylesterase expressed in human intestine, is an increasingly important enzyme in anti-cancer combined therapies for the treatment of different pathologies like colon adenocarcinoma and malignant glioma. The production of human recombinant CES2, in human embryonic kidney cells (HEK-293T cells) using serum-free media, is herein described. CES2 secretion to the media was achieved by the simple addition of an in-frame C-terminal 10× histidine tag (CES2-10xHis) without the need of addition of extra N-terminal signalling sequences or the mutation or deletion of the C-terminal HTEL motif responsible for retaining the protein in the lumen of endoplasmic reticulum. This secretion allowed a fourfold increase in CES2 production. The characterization of human recombinant CES2 showed that this protein exists in other active and inactive forms than the described 60 kDa monomer.

Prodrugs for amines.

The purpose of this work is to review the published strategies for the production of prodrugs of amines. The review is divided in two main groups of approaches: those that rely on enzymatic activation and those that take advantage of physiological chemical conditions for release of the drugs. A compilation of the most important approaches is presented in the form of a table, where the main advantages and disadvantages of each strategy are also referred.