DESIGN, SYNTHESIS AND BIOLOGICAL EVALUATION OF NEW AGENTS TARGETING ESTROGEN RECEPTOR-ALPHA AND -BETA

The two known estrogen receptors, ERa and ERb, are the products of different genes on separate chromosomes. Of these, ERa has been the most extensively studied, and its expression in breast cancer determines the ER+ phenotype. ERb, on the other hand, was discovered only recently and its role in breast cancer pathology remains unclear. ERb inhibits E2-induced proliferation of T47D breast cancer cells in addition to decreasing the expression of cell cycle related genes. Clinical studies have shown a positive correlation between ERâ expression with disease-free survival and overall survival in breast cancer patients. ERb activation with a selective ERb agonist could antagonize the stimulating activity of the ERa in breast cancer cells, and such an ERb agonist could help overcome acquired resistance. Therefore, this work began a search for such agents. A one-pot hydrozirconation-transmetallation-aldimine addition sequence that leads to allylic amides, homoallylic amides and C-cyclopropylalkylamides was significantly accelerated by microwave technology and used for library preparation. The conventional methodology provided a first generation discovery library. A potentially antiestrogenic compound was identified in a transcriptional screening assay from this library, C-cyclopropylalkylamide 26a (O-ethyl-N-{2-[(1S*,2R*)-2-{(R*)[(diphenylphosphinoyl)amino](phenyl)methyl}cyclopropyl]-ethyl}-N-[(4-methylphenyl)sulfonyl]carbamate; a.k.a. CK1-183).Following up on these findings and with the goal to expand the scope of the synthesis methodology, a second generation library of allylic amides and C-cyclopropylalkylamides was prepared. The new library was screened in a fluorescence polarization based homogenous in vitro assay at ERa, and hits were further evaluated in cell-based assays. Three new C-cyclopropylalkylamides, 37c, 37a and 39c, were identified with improved potency over the lead agent 26a against 17b-estradiol (E2) stimulated MCF-7 cells. This second generation library was screened against both ERs. The screening results served to build an SAR model of allylic amides and C-cyclopropylalkylamides at ERa and ERb. A hit from the ERa screen, C-cyclopropylalkylamide 37d (N-(R*)-(((1R*,2R*)-2-butylcyclopropyl)-(4-(phenyl)phenyl)methyl)benzamide), contained a biphenyl core and served as a starting point for the design and synthesis of a third generation of C-cyclopropylalkylamide ER targeting agents. Biphenyl C-cyclopropylalkylamides represent novel structural scaffolds for design and synthesis of ERa and ERb targeting agents and a novel avenue for selective estrogen receptor modulator (SERM) development

Summer undergraduate research: A new pipeline for pain clinical practice and research

BACKGROUND: Most medical schools fail to provide adequate training of clinicians in the treatment of pain. Similarly, despite the fact that over 1/3 of Americans suffer from chronic pain, National Institutes of Health (NIH) funding for pain represents only ~1 % of the NIH budget. These issues may dissuade students from pursing pain in their clinical and research careers. To address these gaps in training and funding, we argue that exposing students to pain science early in their careers, at the undergraduate level, may be an effective method to develop a pipeline for future pain clinicians and scientists. To highlight our argument, we will describe our recent successful implementation of a cross-disciplinary and community-engaged biomedical summer research program. The Pain Undergraduate Research Experience (PURE) summer program involved both off-site and on-site experiences to expose undergraduate students to the range of careers in the pain field from basic science to clinical practice. The objective of the 10-week long PURE program was to evaluate whether a combination of basic science research, clinical practice visits, and patient interactions would increase student understanding of and exposure to the underlying science of pain. METHODS: A pre-post cohort study was used without a comparison group. Entry and exit surveys were used to evaluate students’ perceptions about pain clinical practice and research, student interest in pain, and student confidence about communicating about pain and doing basic science pain research. RESULTS: Students reported significant increases to a number of questions in the survey. Questions were scored on 5 point Likert scales and there was significant increases in student understanding of what life is like with chronic pain (2.6 vs 4.3 post survey), their confidence in explaining pain to a patient (2.8 vs 4.1) or researcher (2.8 vs 4), and their comfort with pain terminology(2.8 vs 3.9). CONCLUSIONS: With the PURE program, we wanted to entice top undergraduates to consider pain as a future area of study, practice, and/or research. We present a model that can be easily implemented at research universities throughout the United States

Quality by design approach identifies critical parameters driving oxygen delivery performance in vitro for perfluorocarbon based artificial oxygen carriers

Perfluorocarbons (PFCs) exhibiting high solubility for oxygen are attractive materials as artificial oxygen carriers (AOC), an alternative to whole blood or Haemoglobin-based oxygen carriers (HBOCs). PFC-based AOCs, however, met clinical translation roadblocks due to product quality control challenges. To overcome these issues, we present an adaptation of Quality by Design (QbD) practices to optimization of PFC nanoemulsions (PFC-NEs) as AOCs. QbD elements including quality risk management, design of experiments (DoE), and multivariate data analysis facilitated the identification of composition and process parameters that strongly impacted PFC colloidal stability and oxygen transport function. Resulting quantitative relationships indicated a composition-driven tradeoff between stability and oxygen transport. It was found that PFC content was most predictive of in vitro oxygen release, but the PFC type (perfluoro-15-crown-5-ether, PCE or perfluorooctyl bromide, PFOB) had no effect on oxygen release. Furthermore, we found, under constant processing conditions, all PFC-NEs, comprised of varied PFC and hydrocarbon content, exhibited narrow droplet size range (100-150 nm) and narrow size distribution. Representative PFOB-NE maintained colloidal attributes upon manufacturing on larger scale (100 mL). QbD approach offers unique insights into PFC AOC performance, which will overcome current product development challenges and accelerate clinical translation

Macrophage-Targeted Nanomedicines for ARDS/ALI: Promise and Potential

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are characterized by progressive lung impairment typically triggered by inflammatory processes. The mortality toll for ARDS/ALI yet remains high because of the poor prognosis, lack of disease-specific inflammation management therapies, and prolonged hospitalizations. The urgency for the development of new effective therapeutic strategies has become acutely evident for patients with coronavirus disease 2019 (COVID-19) who are highly susceptible to ARDS/ALI. We propose that the lack of target specificity in ARDS/ALI of current treatments is one of the reasons for poor patient outcomes. Unlike traditional therapeutics, nanomedicine offers precise drug targeting to inflamed tissues, the capacity to surmount pulmonary barriers, enhanced interactions with lung epithelium, and the potential to reduce off-target and systemic adverse effects. In this article, we focus on the key cellular drivers of inflammation in ARDS/ALI: macrophages. We propose that as macrophages are involved in the etiology of ARDS/ALI and regulate inflammatory cascades, they are a promising target for new therapeutic development. In this review, we offer a survey of multiple nanomedicines that are currently being investigated with promising macrophage targeting potential and strategies for pulmonary delivery. Specifically, we will focus on nanomedicines that have shown engagement with proinflammatory macrophage targets and have the potential to reduce inflammation and reverse tissue damage in ARDS/ALI. Graphical abstract: [Figure not available: see fulltext.

Multiple Linear Regression Predictive Modeling of Colloidal and Fluorescence Stability of Theranostic Perfluorocarbon Nanoemulsions

Perfluorocarbon nanoemulsions (PFC-NEs) are widely used as theranostic nanoformulations with fluorescent dyes commonly incorporated for tracking PFC-NEs in tissues and in cells. Here, we demonstrate that PFC-NE fluorescence can be fully stabilized by controlling their composition and colloidal properties. A quality-by-design (QbD) approach was implemented to evaluate the impact of nanoemulsion composition on colloidal and fluorescence stability. A full factorial, 12-run design of experiments was used to study the impact of hydrocarbon concentration and perfluorocarbon type on nanoemulsion colloidal and fluorescence stability. PFC-NEs were produced with four unique PFCs: perfluorooctyl bromide (PFOB), perfluorodecalin (PFD), perfluoro(polyethylene glycol dimethyl ether) oxide (PFPE), and perfluoro-15-crown-5-ether (PCE). Multiple linear regression modeling (MLR) was used to predict nanoemulsion percent diameter change, polydispersity index (PDI), and percent fluorescence signal loss as a function of PFC type and hydrocarbon content. The optimized PFC-NE was loaded with curcumin, a known natural product with wide therapeutic potential. Through MLR-supported optimization, we identified a fluorescent PFC-NE with stable fluorescence that is unaffected by curcumin, which is known to interfere with fluorescent dyes. The presented work demonstrates the utility of MLR in the development and optimization of fluorescent and theranostic PFC nanoemulsions

Macrophage targeted theranostics as personalized nanomedicine strategies for inflammatory diseases

Inflammatory disease management poses challenges due to the complexity of inflammation and inherent patient variability, thereby necessitating patient-specific therapeutic interventions. Theranostics, which integrate therapeutic and imaging functionalities, can be used for simultaneous imaging and treatment of inflammatory diseases. Theranostics could facilitate assessment of safety, toxicity and real-time therapeutic efficacy leading to personalized treatment strategies. Macrophages are an important cellular component of inflammatory diseases, participating in varied roles of disease exacerbation and resolution. The inherent phagocytic nature, abundance and disease homing properties of macrophages can be targeted for imaging and therapeutic purposes. This review discusses the utility of theranostics in macrophage ablation, phenotype modulation and inhibition of their inflammatory activity leading to resolution of inflammation in several diseases

The First Scale-Up Production of Theranostic Nanoemulsions

Theranostic nanomedicines are a promising new technological advancement toward personalized medicine. Although much progress has been made in pre-clinical studies, their clinical utilization is still under development. A key ingredient for successful theranostic clinical translation is pharmaceutical process design for production on a sufficient scale for clinical testing. In this study, we report, for the first time, a successful scale-up of a model theranostic nanoemulsion. Celecoxib-loaded near-infrared-labeled perfluorocarbon nanoemulsion was produced on three levels of scale (small at 54 mL, medium at 270 mL, and large at 1,000 mL) using microfluidization. The average size and polydispersity were not affected by the equipment used or production scale. The overall nanoemulsion stability was maintained for 90 days upon storage and was not impacted by nanoemulsion production scale or composition. Cell-based evaluations show comparable results for all nanoemulsions with no significant impact of nanoemulsion scale on cell toxicity and their pharmacological effects. This report serves as the first example of a successful scale-up of a theranostic nanoemulsion and a model for future studies on theranostic nanomedicine production and development

Targeting Neuroimmune Interactions in Diabetic Neuropathy with Nanomedicine

Diabetes is a major source of neuropathy and neuropathic pain that is set to continue growing in prevalence. Diabetic peripheral neuropathy (DPN) and pain associated with diabetes are not adequately managed by current treatment regimens. Perhaps the greatest difficulty in treating DPN is the complex pathophysiology, which involves aspects of metabolic disruption and neurotrophic deficits, along with neuroimmune interactions. There is, therefore, an urgent need to pursue novel therapeutic options targeting the key cellular and molecular players. To that end, cellular targeting becomes an increasingly compelling drug delivery option as our knowledge of neuroimmune interactions continues to mount. These nanomedicine-based approaches afford a potentially unparalleled specificity and longevity of drug targeting, using novel or established compounds, all while minimizing off-target effects. The DPN therapeutics directly targeted at the nervous system make up the bulk of currently available treatment options. However, there are significant opportunities based on the targeting of non-neuronal cells and neuroimmune interactions in DPN. Nanomedicine-based agents represent an exciting opportunity for the treatment of DPN with the goals of improving the efficacy and safety profile of analgesia, as well as restoring peripheral neuroregenerative capacity. 36, 122-143