1.Phenylalanine requirements of enterally fed term and preterm neonates.
Hogewind-Schoonenboom JE1, Zhu L1, Zhu L1, Ackermans EC1, Mulders R1, Te Boekhorst B1, Wijnen M1, Bijnevelt L1, Voortman GJ1, Schierbeek H1, Huang L1, de Groof F1, Vermes A1, Chen C1, Huang Y1, van Goudoever JB2. Am J Clin Nutr. 2015 Jun;101(6):1155-62. doi: 10.3945/ajcn.114.089664. Epub 2015 Apr 29.
BACKGROUND: Phenylalanine, which is an essential aromatic amino acid, is either used for protein synthesis or irreversibly hydroxylated to tyrosine. The provision of optimal amounts of dietary phenylalanine is not only important for growth and development but might also influence catecholamine synthesis and release rates. The current recommended aromatic amino acid requirement for infants aged 0-6 mo is based on the amino acid content of human milk.
2.H89 enhances the sensitivity of cancer cells to glyceryl trinitrate through a purinergic receptor-dependent pathway.
Cortier M1,2,3, Boina-Ali R1,2,3, Racoeur C1,2,3, Paul C1,2,3, Solary E2,4,5, Jeannin JF1,2,3, Bettaieb A1,2,3. Oncotarget. 2015 Mar 30;6(9):6877-86.
High doses of the organic nitrate glyceryl trinitrate (GTN), a nitric oxide (NO) donor, are known to trigger apoptosis in human cancer cells. Here, we show that such a cytotoxic effect can be obtained with subtoxic concentrations of GTN when combined with H89, N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulphonamide.2HCl. This synergistic effect requires the generation of reactive oxygen species (ROS) from H89 and NO from GTN treatment that causes cGMP production and PKG activation. Furthermore, the GTN/H89 synergy was attenuated by inhibition of P2-purinergic receptors with suramin and competition with ATP/UDP. By down-regulating genes with antisense oligonucleotides, P2-purinergic receptors P2X3, P2Y1, and P2Y6 were found to have a role in creating this cytotoxic effect. Thus, H89 likely acts as an ATP mimetic synergizing with GTN to trigger apoptosis in aggressive cancer cells.
3.Targeting CD44 expressing cancer cells with anti-CD44 monoclonal antibody improves cellular uptake and antitumor efficacy of liposomal doxorubicin.
Arabi L1, Badiee A2, Mosaffa F3, Jaafari MR4. J Control Release. 2015 Dec 28;220(Pt A):275-86. doi: 10.1016/j.jconrel.2015.10.044. Epub 2015 Oct 27.
Although liposomes improve the safety and pharmacokinetic properties of free drugs, they have not sufficiently enhanced the therapeutic efficacy compared to them. To address this problem, targeted therapy of tumor cells holds great promise to further enhance therapeutic index and decreases off-target effects compared with non-targeted liposomes. In the context of antibody-mediated targeted cancer therapy, we evaluated the anti-tumor activity and therapeutic efficacy of Doxil, and that of Doxil modified with a monoclonal antibody (mAb) against CD44, which is one of the most well-known surface markers associated with Cancer Stem Cells (CSCs). Flow cytometry analyses and confocal laser scanning microscopy results showed significant enhanced cellular uptake of CD44-targeted Doxil (CD44-Doxil) in CD44-positive C-26 cells compared to Doxil. However, CD44-negative NIH-3T3 cells showed a similar uptake and in vitro cytotoxicity with both CD44-Doxil and non-targeted Doxil.
4.Preclinical studies of the potent and selective nicotinic α4β2 receptor ligand VMY-2-95.
Kong H1, Song JK, Yenugonda VM, Zhang L, Shuo T, Cheema AK, Kong Y, Du GH, Brown ML. Mol Pharm. 2015 Feb 2;12(2):393-402. doi: 10.1021/mp5003569. Epub 2015 Jan 20.
The discovery and development of small molecules that antagonize neuronal nicotinic acetylcholine receptors may provide new ligands for evaluation in models of depression or addiction. We discovered a small molecule, VMY-2-95, a nAChR ligand with picomolar affinity and high selectivity for α4β2 receptors. In this study, we investigated its preclinical profile in regards to solubility, lipophilicity, metabolic stability, intestinal permeability, bioavailability, and drug delivery to the rat brain. Metabolic stability of VMY-2-95·2HCl was monitored on human liver microsomes, and specific activity of VMY-2-95·2HCl on substrate metabolism by CYP1A2, 2C9, 2C19, 2D6, and 3A4 was tested in a high-throughput manner. The intestinal transport of VMY-2-95·2HCl was studied through Caco-2 cell monolayer permeability. VMY-2-95·2HCl was soluble in water and chemically stable, and the apparent partition coefficient was 0.682. VMY-2-95·2HCl showed significant inhibition of CYP2C9 and 2C19, but weak or no effect on 1A2, 2D6, and 3A4.