(2-Hydroxypropyl)-β-Cyclodextrin Is a New Angiogenic Molecule for Therapeutic Angiogenesis

The role of the ERK signaling pathway in promoting angiogenesis for treating ischemic diseases

The main treatment strategy for ischemic diseases caused by conditions such as poor blood vessel formation or abnormal blood vessels involves repairing vascular damage and encouraging angiogenesis. One of the mitogen-activated protein kinase (MAPK) signaling pathways, the extracellular signal-regulated kinase (ERK) pathway, is followed by a tertiary enzymatic cascade of MAPKs that promotes angiogenesis, cell growth, and proliferation through a phosphorylation response. The mechanism by which ERK alleviates the ischemic state is not fully understood. Significant evidence suggests that the ERK signaling pathway plays a critical role in the occurrence and development of ischemic diseases. This review briefly describes the mechanisms underlying ERK-mediated angiogenesis in the treatment of ischemic diseases. Studies have shown that many drugs treat ischemic diseases by regulating the ERK signaling pathway to promote angiogenesis. The prospect of regulating the ERK signaling pathway in ischemic disorders is promising, and the development of drugs that specifically act on the ERK pathway may be a key target for promoting angiogenesis in the treatment of ischemic diseases.

The C5a/C5a receptor 1 axis controls tissue neovascularization through CXCL4 release from platelets

Platelets contribute to the regulation of tissue neovascularization, although the specific factors underlying this function are unknown. Here, we identified the complement anaphylatoxin C5a-mediated activation of C5a receptor 1 (C5aR1) on platelets as a negative regulatory mechanism of vessel formation. We showed that platelets expressing C5aR1 exert an inhibitory effect on endothelial cell functions such as migration and 2D and 3D tube formation. Growth factor- and hypoxia-driven vascularization was markedly increased in C5ar1^-/- mice. Platelet-specific deletion of C5aR1 resulted in a proangiogenic phenotype with increased collateralization, capillarization and improved pericyte coverage. Mechanistically, we found that C5a induced preferential release of CXC chemokine ligand 4 (CXCL4, PF4) from platelets as an important antiangiogenic paracrine effector molecule. Interfering with the C5aR1-CXCL4 axis reversed the antiangiogenic effect of platelets both in vitro and in vivo.In conclusion, we identified a mechanism for the control of tissue neovascularization through C5a/C5aR1 axis activation in platelets and subsequent induction of the antiangiogenic factor CXCL4.

Supramolecular Pharmaceutical Sciences: A Novel Concept Combining Pharmaceutical Sciences and Supramolecular Chemistry with a Focus on Cyclodextrin-Based Supermolecules

Supramolecular chemistry is an extremely useful and important domain for understanding pharmaceutical sciences because various physiological reactions and drug activities are based on supramolecular chemistry. However, it is not a major domain in the pharmaceutical field. In this review, we propose a new concept in pharmaceutical sciences termed "supramolecular pharmaceutical sciences," which combines pharmaceutical sciences and supramolecular chemistry. This concept could be useful for developing new ideas, methods, hypotheses, strategies, materials, and mechanisms in pharmaceutical sciences. Herein, we focus on cyclodextrin (CyD)-based supermolecules, because CyDs have been used not only as pharmaceutical excipients or active pharmaceutical ingredients but also as components of supermolecules.

Metallocyclodextrins in medicinal chemistry

This review focuses on metal complexes of cyclodextrin (CyD) derivatives designed for application as therapeutics or diagnostics. We discuss examples of metalloprotein models (hemoglobin, superoxide dismutase and catalase) based on cyclodextrins. The hydrophobic microenvironment of CyDs stabilizes the Fe(II) porphyrin system that can reversibly bind O₂ or CO in water. Superoxide dismutase/catalase mimetics exploit functionalization with CyDs, which increase their solubility and biological activity. Furthermore, CyDs have been used as scaffolds to obtain multicenter metal complexes: paramagnetic systems act as high-performance contrast agents for magnetic resonance imaging applications. Finally, we review CyD ligands, whose use appears promising in metal chelation therapy, as CyD moiety confers additional properties to the ligands.

Oligo(ethylene glycol)-modified β-cyclodextrin-based polyrotaxanes for simultaneously modulating solubility and cellular internalization efficiency

We developed stimuli-labile polyrotaxanes (PRXs) composed of β-cyclodextrin (β-CD), Pluronic as an axle polymer, and acid-cleavable N-triphenylmethyl groups as bulky stopper molecules, and found that the PRXs are potent therapeutics for Niemann-Pick type C disease, because the PRX can effectively reduce intracellular cholesterol through the intracellular release of threaded β-CDs. In general, the PRXs need to be chemically modified with hydrophilic functional groups because PRXs are not soluble in aqueous media. Herein, four series of oligo(ethylene glycol)s (OEGs) with different ethylene glycol repeating unit (2 or 3) and chemical structure of OEG terminal (hydroxy or methoxy) were modified onto the threaded β-CDs in PRX. The effects of the structure of OEG on the aqueous solubility, toxicity, and cellular internalization efficiency of OEG-modified PRXs were investigated to optimize the chemical structure of OEG. The hydroxy-terminated OEG-modified PRXs showed excellent solubility in aqueous media and no toxicity, regardless of the number of ethylene glycol repeating units. In the case of the methoxy-terminated OEG-modified PRXs, sufficient solubility in aqueous media and negligible toxicity were observed when the number of ethylene glycol repeating units was 3, while low solubility and toxicity were observed when the ethylene glycol repeating unit was 2. Additionally, cellular uptake levels of methoxy-terminated OEG-modified PRXs in RAW264.7 cells were higher than those of hydroxy-terminated OEG-modified PRXs. Consequently, the chemical structure of the OEG strongly affects the chemical and biological properties of the PRXs, and that a methoxy-terminated OEG with 3 ethylene glycol repeating units is the most preferable modification of PRXs, since the resultant PRX is sufficiently soluble in aqueous media, non-toxic, and possesses high cellular internalization efficiency.

The association of functional polymorphisms in genes encoding growth factors for endothelial cells and smooth muscle cells with the severity of coronary artery disease

Background

Despite the important roles of vascular smooth muscle cells and endothelial cells in atherosclerotic lesion formation, data regarding the associations of functional polymorphisms in the genes encoding growth factors with the severity of coronary artery disease (CAD) are lacking. The aim of the present study is to analyze the relationships between functional polymorphisms in genes encoding basic fibroblast growth factor (bFGF, FGF2), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), platelet derived growth factor-B (PDGFB), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor A (VEGF-A) and the severity of coronary atherosclerosis in patients with stable CAD undergoing their first coronary angiography.

Methods

In total, 319 patients with stable CAD who underwent their first coronary angiography at the Silesian Centre for Heart Diseases in Zabrze, Poland were included in the analysis. CAD burden was assessed using the Gensini score. The TaqMan method was used for genotyping of selected functional polymorphisms in the FGF2, PDGFB, TGFB1, IGF1 and VEGFA genes, while rs4444903 in the EGF gene was genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The associations between the selected polymorphisms and the Gensini were calculated both for the whole cohort and for a subgroup of patients without previous myocardial infarction (MI).

Results

There were no differences in the distribution of the Gensini score between the genotypes of the analyzed polymorphisms in FGF2, EGF, IGF1, PDFGB, and TGFB1 in the whole cohort and in the subgroup of patients without previous MI. The Gensini score for VEGFA rs699947 single-nucleotide polymorphism (SNP) in patients without previous myocardial infarction, after correction for multiple testing, was highest in patients with the A/A genotype, lower in heterozygotes and lowest in patients with the C/C genotype, (p value for trend = 0.013, false discovery rate (FDR) = 0.02). After adjustment for clinical variables, and correction for multiple comparisons the association between the VEGFA genotype and Gensini score remained only nominally significant (p = 0.04, FDR = 0.19) under the dominant genetic model in patients without previous MI.

Conclusions

We were unable to find strong association between analyzed polymorphisms in growth factors and the severity of coronary artery disease, although there was a trend toward association between rs699947 and the severity of CAD in patients without previous MI.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-016-0402-4) contains supplementary material, which is available to authorized users.