Preclinical development of a miR-132 inhibitor for heart failure treatment.

Despite proven efficacy of pharmacotherapies targeting primarily global neurohormonal dysregulation, heart failure (HF) is a growing pandemic with increasing burden. Treatments mechanistically focusing at the cardiomyocyte level are lacking. MicroRNAs (miRNA) are transcriptional regulators and essential drivers of disease progression. We previously demonstrated that miR-132 is both necessary and sufficient to drive the pathological cardiomyocytes growth, a hallmark of adverse cardiac remodelling. Therefore, miR-132 may serve as a target for HF therapy. Here we report further mechanistic insight of the mode of action and translational evidence for an optimized, synthetic locked nucleic acid antisense oligonucleotide inhibitor (antimiR-132). We reveal the compound's therapeutic efficacy in various models, including a clinically highly relevant pig model of HF. We demonstrate favourable pharmacokinetics, safety, tolerability, dose-dependent PK/PD relationships and high clinical potential for the antimiR-132 treatment scheme.

Critical evaluation of quantification methods for oligonucleotides formulated in lipid nanoparticles.

There is a very large variety in the types of nanoparticulate lipid formulations for oligonucleotides, and remarkably, also a very large heterogeneity in the methods that are used for analyzing oligonucleotide load, encapsulation efficiency and oligonucleotide release. Furthermore, a literature survey showed that the extent to which these procedures are reported in scientific literature varies greatly, with some of them not even reporting any quantification at all. This greatly hampers the reproducibility of nanoparticle preparation between different researchers and between different laboratories, which slows down the clinical translation of such nanomedicines. In this work, a standardized extraction method from liposomes is proposed, in which potential contaminants from the carrier are removed by a simple extraction of the oligonucleotides. These extracts were then analyzed with seven commonly used methods for oligonucleotide quantification, including several absorbance based methods and the most commonly applied dye binding assay. Strikingly, differences in absolute values up to fourfold were found when the same sample was analyzed using different methods which should be taken into consideration when reports using different methods are compared. Furthermore, these results indicate that the most commonly applied method, the dye binding assay, may -without adaptations- not be suitable for short oligonucleotides like siRNAs. The found differences in quantification methods as described here underscore the need for proper documentation of methods to correctly interpret published results, which -with regard to oligonucleotide analysis- is currently lacking in many reports.

Isolation of eudesmanes from Pluchea odorata and evaluation of their effects on cancer cell growth and tumor invasiveness in vitro.

The traditionally used Central American medicinal plant Pluchea odorata, known as an anti-inflammatory and cancer cell growth-inhibiting remedy, was subjected to bioassay-guided isolation. Structure elucidation by 1D- and 2D-NMR and MS techniques supported by ECD and UV spectroscopic data revealed seven structurally previously undescribed and eight known eudesmane-type sesquiterpenes. Furthermore, one previously undescribed and one known phytol-like alcohol were identified. All compounds were tested for their cytotoxicity in cancer cells and for their anti-invasive effects. Among the eudesmanes, 3α-(2',3'-epoxy-2'-methylbutyryloxy)-4α-hydroxy-11-hydroperoxy-eudesm-6-en-8-one exhibited the most potent cytotoxic activity with an IC50 value of 8.8 µM (after 48 h). Also in an in vitro model measuring the tumor-triggered breaching of the adjacent lymph endothelial cell barrier (3S*,4R*,5S*,10S*,2'R*,3'R*)-3-(2',3'-epoxy-2'-methylbutyryloxy)-4,7-dihydroxy-eudesm-11-en-8-one (IC75 = 47 µM) and (3S*,4R*,5R*,10S*,2'R*,3'R*)-3-(2',3'-epoxy-2'-methylbutyryloxy)-4-acetyloxy-6-methoxy-11-hydroxy-eudesm-6-en-8-one (IC75 = 73 µM) showed inhibitory activities. Furthermore, preliminary structure-activity relationships (SARs) of the eudesmanes were developed.

Triterpenoic Acids from Apple Pomace Enhance the Activity of the Endothelial Nitric Oxide Synthase (eNOS).

Pomace is an easy-accessible raw material for the isolation of fruit-derived compounds. Fruit consumption is associated with health-promoting effects, such as the prevention of cardiovascular disease. Increased vascular nitric oxide (NO) bioavailability, for example, due to an enhanced endothelial nitric oxide synthase (eNOS) activity, could be one molecular mechanism mediating this effect. To identify compounds from apple (Malus domestica Borkh.) pomace that have the potential to amplify NO bioavailability via eNOS activation, a bioassay-guided fractionation of the methanol/water (70:30) extract has been performed using the (14)C-L-arginine to (14)C-L-citrulline conversion assay (ACCA) in the human endothelium-derived cell line EA.hy926. Phytochemical characterization of the active fractions was performed using the spectrophotometric assessment of the total phenolic content, as well as TLC, HPLC-DAD-ELSD, and HPLC-MS analyses. Eleven triterpenoic acids, of which one is a newly discovered compound, were identified as the main constituents in the most active fraction, accompanied by only minor contents of phenolic compounds. When tested individually, none of the tested compounds exhibited significant eNOS activation. Nevertheless, cell stimulation with the reconstituted compound mixture restored eNOS activation, validating the potential of apple pomace as a source of bioactive components.

Dietary small molecules and large-scale gene expression studies: an experimental approach for understanding their beneficial effects on the development of malignant and non-malignant proliferative diseases.

Epidemiological studies have repeatedly demonstrated a correlation between nutrition, development and the severity of malignant and non-malignant proliferative diseases such as cancer and atherosclerosis. Therefore, the prevention of chronic proliferative diseases through dietary intervention is currently receiving considerable attention. Until now, much of the research is being focused on the cellular and molecular action mechanisms of dietary small molecules explaining their beneficial effects. Dietary chemicals may affect gene expression in several human diseases. However, significant progress has been made and several molecular action mechanisms have been proposed. Alteration of genetical pathways by nutrition, also called "Nutrigenomics", may offer a new approach for understanding the beneficial effects of dietary compounds on the development of severe polygenic diseases, such as cardiovascular disease, diabetes and hypertension. This review focuses on the nutritional genomics of dietary chemicals with a special emphasis on catechins. Catechins belong to the flavonoid family, which are polyphenolic compounds available in foods of plant origin. Several epidemiological studies have reported that consumption of flavonoids, and especially catechins might function as chemopreventive agents against cancer and cardiovascular diseases.