Human Neutrophil Elastase Induce Interleukin-10 Expression in Peripheral Blood Mononuclear Cells through Protein Kinase C Theta/Delta and Phospholipase Pathways.

OBJECTIVE: Neutrophils have an important role in the rapid innate immune response, and the release or active secretion of elastase from neutrophils is linked to various inflammatory responses. Purpose of this study was to determine how the human neutrophil elastase affects the interleukin-10 (IL-10) response in peripheral blood mononuclear cells (PBMC). MATERIALS AND METHODS: In this prospective study, changes in IL-10 messenger RNA (mRNA) and protein expression levels in monocytes derived from human PBMCs were investigated after stimulation with human neutrophil elastase (HNE). A set of inhibitors was used for examining the pathways for IL-10 production induced by HNE. RESULTS: Reverse transcription polymerase chain reaction (RT-PCR) showed that stimulation with HNE upregulated IL-10 mRNA expression by monocytes, while the enzyme-linked immunosorbent assay (ELISA) revealed an increase of IL-10 protein level in the culture medium. A phospholipase C inhibitor (U73122) partially blunt- ed the induction of IL-10 mRNA expression by HNE, while IL-10 mRNA expression was significantly reduced by a protein kinase C (PKC) inhibitor (Rottlerin). A calcium chelator (3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester: TMB-8) inhibited the response of IL-10 mRNA to stimulation by HNE. In addition, pretreatment with a broad-spectrum PKC inhibitor (Ro-318425) partly blocked the response to HNE. Finally, an inhibitor of PKC theta/delta abolished the increased level of IL-10 mRNA expression. CONCLUSION: These results indicate that HNE mainly upregulates IL-10 mRNA ex- pression and protein production in moncytes via a novel PKC theta/delta, although partially via the conventional PKC pathway.

A novel class of antihyperlipidemic agents with low density lipoprotein receptor up-regulation via the adaptor protein autosomal recessive hypercholesterolemia.

We have previously reported compound 2 as a inhibitor of acyl-coenzyme A:cholesterol O-acyltransferase (ACAT) and up-regulator of the low density lipoprotein receptor (LDL-R) expression. In this study we focused on compound 2, a unique LDL-R up-regulator, and describe the discovery of a novel class of up-regulators of LDL-R. Replacement the methylene urea linker in compound 2 with an acylsulfonamide linker kept a potent LDL-R up-regulatory activity, and subsequent optimization work gave compound 39 as a highly potent LDL-R up-regulator (39; EC(25) = 0.047 microM). Compound 39 showed no ACAT inhibitory activity even at 1 microM. The sodium salts of compound 39 reduced plasma total and LDL cholesterol levels in a dose-dependent manner in an experimental animal model of hyperlipidemia. Moreover, we revealed in this study using RNA interference that autosomal recessive hypercholesterolemia (ARH), an adaptor protein of LDL-R, is essential for compound 39 up-regulation of LDL-R expression.

Reduction of myocardial infarct size by SM-197378, a novel Na+/H+ exchange inhibitor, in rabbits.

The effects of SM-197378, 2-[[[amino(imino)methyl]amino]carbonyl]-1-methyl-4-trifluoromethyl-1H-indol-7-yl=hydrogen=sulfate monohydrate, a novel potent Na+/H+exchange inhibitor, on heart injury were studied using a rabbit model involving 30 min of myocardial ischemia and 5 h of reperfusion. Intravenous administration of SM-197378 before ischemia reduced the infarct size by approximately 30-50% in a dose-dependent manner. This anti-necrotic effect was achieved without significant hemodynamic changes. Moreover, administration of SM-197378 before reperfusion also resulted in a significant, approximately 30-40%, reduction in the infarct size. The anti-necrotic effect of pre-ischemic bolus treatment with SM-197378 was compared with that of nicorandil, a K+channel opener with nitrate-like activity, and ischemic preconditioning. With 30 and 60 min of ischemia, the anti-necrotic effects of SM-197378 and ischemic preconditioning were similar and superior to that of nicorandil. With 90 min of ischemia, the anti-necrotic effect of SM-197378 was superior to that of ischemic preconditioning.

Discovery of hydroxamic acid analogs as dual inhibitors of phosphodiesterase-1 and -5.

HTS and the following synthesis of a series of the compounds led us to the discovery of hydroxamic acid analogs as potent dual inhibitors of phosphodiesterase (PDE)-1 and 5. These compounds have highly related structure and deviation of the structure usually resulted in reduced potency. This result can be used to design other molecules that may be utilized for the therapy of cardiovascular symptoms that relates to cGMP level.