Liposomal PHD2 Inhibitors and the Enhanced Efficacy in Stabilizing HIF-1α

Nanoparticles targeting the central circadian clock: Potential applications for neurological disorders

Circadian rhythms and their involvement with various human diseases, including neurological disorders, have become an intense area of research for the development of new pharmacological treatments. The location of the circadian clock machinery in the central nervous system makes it challenging to reach molecular targets at therapeutic concentrations. In addition, a timely administration of the therapeutic agents is necessary to efficiently modulate the circadian clock. Thus, the use of nanoparticles in circadian clock dysfunctions may accelerate their clinical translation by addressing these two key challenges: enhancing brain penetration and/or enabling their formulation in chronodelivery systems. This review describes the implications of the circadian clock in neurological pathologies, reviews potential molecular targets and their modulators and suggests how the use of nanoparticle-based formulations could improve their clinical success. Finally, the potential integration of nanoparticles into chronopharmaceutical drug delivery systems will be described.

PHD-2/HIF-1α axis mediates doxorubicin-induced angiogenesis in SH-SY5Y neuroblastoma microenvironment: a potential survival mechanism

The response of neuroblastoma (NB) cells to chemotherapeutics and their influence on NB microenvironment remain incompletely understood. Herein, we examined the underlying molecular mechanism via which Doxorubicin, a chemotherapeutic agent used for NB treatment, promotes proangiogenic response in the SH-SY5Y microenvironment. Doxorubicin treatment at 1 µg/ml reduced SH-SY5Y cell proliferation and primed the apoptosis pathway. Unexpectedly, SH-SY5Y cells treated with doxorubicin upregulated their expression of the pro-angiogenic factors, including vascular endothelial growth factor (VEGF), platelets-derived growth factor (PDGF), and matrix metalloprotease-2 (MMP-2) and secretion of nitric oxide. To assess the functional angiogenesis of SH-SY5Y cells pre-treated with doxorubicin, an indirect co-culture system with human umbilical vein endothelial cells (HUVEC) was established. These HUVECs acquired enhanced proliferation, migration capacity, and tube formation capability and exhibited increased nitric oxide (NO) production, in addition to upregulated α-smooth muscle actin expression, suggesting enhanced contractility. In-ovo studies of the neo-angiogenic response of SH-SY5Y pre-treated with doxorubicin further show their promoted neo-angiogenesis as indicated by the generated blood vessels and histological analysis of CD31 expression. Inhibition of PHD-2 could be a potential target for doxorubicin, as indicated by molecular docking, molecular dynamics (MD) simulation, and MM-GBSA calculations, leading to hypoxia-inducible factor-1 alpha (HIF-1α) stabilization. Bioinformatics analyses and enrichment analyses of RNA-seq data revealed activation of Pi3K pathway which is further validated in-vitro. These results provide evidence of the unexpected pro-angiogenic response of SH-SY5Y cells to doxorubicin treatment and suggest the potential use of multi-modal therapeutic regimens for a more comprehensive approach to NB treatment.

Transfection of hypoxia-inducible factor-1α mRNA upregulates the expression of genes encoding angiogenic growth factors

Hypoxia-Inducible Factor-1α (HIF-1α) has presented a new direction for ischemic preconditioning of surgical flaps to promote their survival. In a previous study, we demonstrated the effectiveness of HIF-1a DNA plasmids in this application. In this study, to avoid complications associated with plasmid use, we sought to express HIF-1α through mRNA transfection and determine its biological activity by measuring the upregulation of downstream angiogenic genes. We transfected six different HIF-1a mRNAs-one predominant, three variant, and two novel mutant isoforms-into primary human dermal fibroblasts using Lipofectamine, and assessed mRNA levels using RT-qPCR. At all time points examined after transfection (3, 6, and 10 h), the levels of HIF-1α transcript were significantly higher in all HIF-1α transfected cells relative to the control (all p < 0.05, unpaired Student's T-test). Importantly, the expression of HIF-1α transcription response genes (VEGF, ANG-1, PGF, FLT1, and EDN1) was significantly higher in the cells transfected with all isoforms than with the control at six and/or ten hours post-transfection. All isoforms were transfected successfully into human fibroblast cells, resulting in the rapid upregulation of all five downstream angiogenic targets tested. These findings support the potential use of HIF-1α mRNA for protecting ischemic dermal flaps.

In silico and in vitro human metabolism of IOX2, a performance-enhancing doping agent

IOX2 is a potent inhibitor of prolyl hydroxylase 2, a key enzyme in the regulation of hypoxia-inducible factor (HIF) and oxygen homeostasis. As such, it can be used to enhance athletic performance and is currently banned by the World Anti-Doping Agency (WADA). Detection of metabolites is critical to demonstrate drug use in doping. However, there is currently little data on IOX2 human metabolism. Our aim was to identify relevant biomarkers of IOX2 use in humans. For this purpose, IOX2 was incubated with 10-donor-pooled human hepatocytes for 3 h, incubates were analyzed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), and LC-HRMS/MS data were screened with Compound Discoverer (Thermo Scientific) for a comprehensive identification of IOX2 metabolites. Additionally, IOX2 human metabolites were predicted with GLORYx open-access software (University of Hamburg, Germany) to assist in the LC-HRMS/MS analysis and data mining. Thirteen metabolites were identified, oxidation at the quinolinyl group, O-glucuronidation, and combinations being predominant biotransformations. The results were consistent with previous animal studies and a single case of oral microdose administration. We suggest hydroxyquinolinyl-IOX2 as major biomarker of IOX2 use in biological samples, glucuronide hydrolysis being critical to increase IOX2 and hydroxyquinolinyl-IOX2 detectability in urine.

Progress on the pathological tissue microenvironment barrier-modulated nanomedicine

Imbalance in the tissue microenvironment is the main obstacle to drug delivery and distribution in the human body. Before penetrating the pathological tissue microenvironment to the target site, therapeutic agents are usually accompanied by three consumption steps: the first step is tissue physical barriers for prevention of their penetration, the second step is inactivation of them by biological molecules, and the third step is a cytoprotective mechanism for preventing them from functioning on specific subcellular organelles. However, recent studies in drug-hindering mainly focus on normal physiological rather than pathological microenvironment, and the repair of damaged physiological barriers is also rarely discussed. Actually, both the modulation of pathological barriers and the repair of damaged physiological barriers are essential in the disease treatment and the homeostasis maintenance. In this review, we present an overview describing the latest advances in the generality of these pathological barriers and barrier-modulated nanomedicine. Overall, this review holds considerable significance for guiding the design of nanomedicine to increase drug efficacy in the future.

Design and fabrication of intracellular therapeutic cargo delivery systems based on nanomaterials: current status and future perspectives

Intracellular cargo delivery, the introduction of small molecules, proteins, and nucleic acids into a specific targeted site in a biological system, is an important strategy for deciphering cell function, directing cell fate, and reprogramming cell behavior. With the advancement of nanotechnology, many researchers use nanoparticles (NPs) to break through biological barriers to achieving efficient targeted delivery in biological systems, bringing a new way to realize efficient targeted drug delivery in biological systems. With a similar size to many biomolecules, NPs possess excellent physical and chemical properties and a certain targeting ability after functional modification on the surface of NPs. Currently, intracellular cargo delivery based on NPs has emerged as an important strategy for genome editing regimens and cell therapy. Although researchers can successfully deliver NPs into biological systems, many of them are delivered very inefficiently and are not specifically targeted. Hence, the development of efficient, target-capable, and safe nanoscale drug delivery systems to deliver therapeutic substances to cells or organs is a major challenge today. In this review, on the basis of describing the research overview and classification of NPs, we focused on the current research status of intracellular cargo delivery based on NPs in biological systems, and discuss the current problems and challenges in the delivery process of NPs in biological systems.

A critical review of Roxadustat formulations, solid state studies, and analytical methodology

This review aims to collate information about the analytical methodologies, bioanalytical methodologies, pharmaceutical formulations, solid-state studies, and the current and future market scenario for a relatively new class of drugs, Roxadustat. Roxadustat is a hypoxia-inducible factor propyl hydroxylase inhibitor that significantly increases blood hemoglobin via the action of transcriptional activator HIF. As the molecule has a promising role in stimulating erythropoiesis, it is considered an ideal therapeutic agent for patients with anemia. In the current review, an attempt has been made to compile the pharmacological, pharmacokinetic, and pharmacodynamic characteristics of Roxadustat and systematically present product development data. This drug has several polymorphs of cocrystal, co-former, and salt, which have been explained in detail in the current work. The comprehensive review summarizes all the chromatographic methods and is presented in table form. This review has extensively covered Liquid chromatography-tandem mass spectrometry methods used to analyze Roxadustat in the biological matrix. The literature needs more data on forced degradation study, impurity profiling, gas chromatography, analytical methods for assay, dissolution, and different formulation aspects of Roxadustat.