Phosphoinositide 3-kinase (PI3K) is the family of lipid kinases participating in vital cellular processes such as cell proliferation, growth, migration, or cytokines production. Due to the high expression of these proteins in many human cells and their involvement in metabolism regulation, normal embryogenesis, or maintaining glucose homeostasis, the inhibition of PI3K (especially the first class which contains four subunits: α, β, γ, δ) is considered to be a promising therapeutic strategy for the treatment of inflammatory and autoimmune diseases such as systemic lupus erythematosus (SLE) or multiple sclerosis. In this work, we synthesized a library of benzimidazole derivatives of pyrazolo[1,5-a]pyrimidine representing a collection of new, potent, active, and selective inhibitors of PI3Kδ, displaying IC50 values ranging from 1.892 to 0.018 μM. Among all compounds obtained, CPL302415 (6) showed the highest activity (IC50 value of 18 nM for PI3Kδ), good selectivity (for PI3Kδ relative to other PI3K isoforms: PI3Kα/δ = 79; PI3Kβ/δ = 1415; PI3Kγ/δ = 939), and promising physicochemical properties. As a lead compound synthesized on a relatively large scale, this structure is considered a potential future candidate for clinical trials in SLE treatment.

Background Proprotein convertase subtilisin/kexin 9 (PCSK9) can increase plasma levels of low-density lipoprotein (LDL) cholesterol (LDL-C) through reducing protein levels of liver LDL receptor (LDLR). PCSK9 inhibition has been found to efficiently alleviate hypercholesterolemia. Purpose In the present study, we prepared nanoliposomal anti-PCSK9 vaccine and evaluated its protective effects against hypercholesterolemia and atherosclerotic plaque formation in C57BL/6 mice fed on atherogenic diet. Methods Nanoliposome formulation containing 1,2-Dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC), 1,2-Dimyristoyl-sn-glycero-3-phosphorylglycerol (DMPG) and cholesterol (Chol) were prepared using the lipid-film hydration method, and used as the vaccine delivery system. Immunogenic peptide called Immunogenic Fused PCSK9-Tetanus (IFPT) was exhibited on the surface of nanoliposome carriers by using DSPE-PEG-Maleimide lipid (L-IFPT) and adsorbed to Alum adjuvant (L-IFPTA+). The prepared vaccine formulations IFPT, L-IFPTA+, IFPTA+, IFPT, and empty liposome as the negative control were subcutaneously administrated four times with a bi-weekly interval in C57BL/6 mice fed on atherogenic diet. Protein levels of liver LDLR, lipid profile, plasma levels of anti-PCSK9 antibody, plasma concentration of PCSK9 protein, and effect of anti-PCSK9 antibody on PCSK9-LDLR interaction were measured in the vaccinated mice. Aortic arch atherosclerotic lesions were studied using hematoxylin and eosin staining. To determine inflammatory response, splenic CD4+producing IL-4 and IFN-γ were evaluated using flow cytometry analysis. Results Among formulated vaccines, the L-IFPTA+vaccine could generate the highest IgG anti-PCSK9 antibody in the vaccinated hypercholesterolemic mice. The generated anti-PCSK9 antibodies inhibited interaction of PCSK9 with LDLR through targeting plasma PCSK9, whereby protein levels of liver LDLR was elevated in the vaccinated mice. As reveled by lipid profile analysis, liposomal vaccines, with more extent the L-IFPTA+vaccine, could significantly decrease plasma TC and LDL-C in hypercholesterolemic mice. Of note, L-IFPTA+ vaccine could reduce size and severity of atherosclerotic lesion in the aorta arch. Importantly, long-term (48 weeks) follow-up of hypercholesterolemic vaccinated mice revealed that L-IFPTA+vaccine could induce a long-lasting humoral immune response against plasma PCSK9, which was accompanied with a significant decrease of TC and LDL-C (Figure). Additionally, Anti-inflammatory Th2 cells and IL-4 cytokine were significantly elevated in splenic cells isolated from hypercholesterolemic vaccinated mice. Figure 1 Conclusions L-IFPTA+vaccine can promote long-lasting, functional and safe anti-PCSK9 antibodies in hypercholesterolemic C57BL/6 mice, revealing long-term protective effect against hypercholesterolemia and atherosclerosis.

Asthma is a common chronic inflammatory disease. Although effective asthma therapies are available, part of asthmatic population do not respond to these treatment options. In this work we present the result of development of CPL302-253 molecule, a selective PI3Kδ inhibitor. This molecule is intended to be a preclinical candidate for dry powder inhalation in asthma treatment. Studies we performed showed that this molecule is safe and effective PI3Kδ inhibitor that can impact many immune functions. We developed a short, 15-day HDM induced asthma mouse model, in which we showed that CPL302-253 is able to block inflammatory processes leading to asthma development in vivo.

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As a member of the class I PI3K family, phosphoinositide 3-kinase δ (PI3Kδ) is an important signaling biomolecule that controls immune cell differentiation, proliferation, migration, and survival. It also represents a potential and promising therapeutic approach for the management of numerous inflammatory and autoimmune diseases. We designed and assessed the biological activity of new fluorinated analogues of CPL302415, taking into account the therapeutic potential of our selective PI3K inhibitor and fluorine introduction as one of the most frequently used modifications of a lead compound to further improve its biological activity. In this paper, we compare and evaluate the accuracy of our previously described and validated in silico workflow with that of the standard (rigid) molecular docking approach. The findings demonstrated that a properly fitted catalytic (binding) pocket for our chemical cores at the induced-fit docking (IFD) and molecular dynamics (MD) stages, along with QM-derived atomic charges, can be used for activity prediction to better distinguish between active and inactive molecules. Moreover, the standard approach seems to be insufficient to score the halogenated derivatives due to the fixed atomic charges, which do not consider the response and indictive effects caused by fluorine. The proposed computational workflow provides a computational tool for the rational design of novel halogenated drugs.