Cellular uptake of antisense oligonucleotides after complexing or conjugation with cell-penetrating model peptides.

The uptake by mammalian cells of phosphorothioate oligonucleotides was compared with that of their respective complexes or conjugates with cationic, cell-penetrating model peptides of varying helix-forming propensity and amphipathicity. An HPLC-based protocol for the synthesis and purification of disulfide bridged conjugates in the 10-100 nmol range was developed. Confocal laser scanning microscopy (CLSM) in combination with gel-capillary electrophoresis and laser induced fluorescence detection (GCE-LIF) revealed cytoplasmic and nuclear accumulationin all cases.

Ht31: the first protein kinase A anchoring protein to integrate protein kinase A and Rho signaling.

In an attempt to isolate protein kinase A anchoring proteins (AKAPs) involved in vasopressin-mediated water reabsorbtion, the complete sequence of the human AKAP Ht31 was determined and a partial cDNA of its rat orthologue (Rt31) was cloned. The Ht31 cDNA includes the estrogen receptor cofactor Brx and the RhoA GDP/GTP exchange factor proto-lymphoid blast crisis (Lbc) sequences. The Ht31 gene was assigned to chromosome 15 (region q24-q25).

Cellular uptake of an alpha-helical amphipathic model peptide with the potential to deliver polar compounds into the cell interior non-endocytically.

Evidence that multiple, probably non-endocytic mechanisms are involved in the uptake into mammalian cells of the alpha-helical amphipathic model peptide FLUOS-KLALKLALKALKAALKLA-NH2 (I) is presented. Extensive cellular uptake of N-terminally GC-elongated derivatives of I, conjugated by disufide bridges to differently charged peptides, indicated that I-like model peptides might serve as vectors for intracellular delivery of polar bioactive compounds. The mode of the cellular internalization of I comprising energy-, temperature-, pH- and ion-dependent as well as -independent processes suggests analogy to that displayed by small unstructured peptides reported previously (Oehlke et al.

Spin trapping using 2,2-dimethyl-2H-imidazole-1-oxides.

The ability of novel cyclic nitrones, 4-substituted 2,2-dimethyl-2H-imidazole-1-oxides (IMO's) to trap a variety of short-lived free radicals has been investigated using ESR spectroscopy. IMO's scavenge oxygen-, carbon- and sulfur-derived free radicals to give persistent nitroxides. Compared to the spin trap 5,5-dimethyl-pyrroline-1-oxide, a higher lifetime of hydroxyl radical adducts and a higher selectivity related to the trapping of carbon-centered radicals was found.

[Potential cardiotonics. 14. Synthesis and in vitro positive inotropic actions of 4-morpholino-5-(4-pyridinyl)pyridine derivatives].

By the reaction of 2-chloro-5-(4-pyridinyl)pyridines 1-6 with morpholine as well as by derivation of the 2-morpholino-pyridine-3-carboxamide 8 the 3-substituted 2-morpholino-5-(4-pyridinyl)pyridines 7-14 were prepared. The evaluation for positive inotropic properties in spontaneously beating isolated guinea pig atria gave for the 3-cyano derivative 7 (AWD 122-14) the best activity. The potency is comparable to that of milrinone and is due to partial by inhibition of phosphodiesterase III (PDE III).