Development of an aerosol intervention for COVID-19 disease: Tolerability of soluble ACE2 (APN01) administered via nebulizer.

As ACE2 is the critical SARS-CoV-2 receptor, we hypothesized that aerosol administration of clinical grade soluble human recombinant ACE2 (APN01) will neutralize SARS-CoV-2 in the airways, limit spread of infection in the lung, and mitigate lung damage caused by deregulated signaling in the renin-angiotensin (RAS) and Kinin pathways. Here, after demonstrating in vitro neutralization of SARS-CoV-2 by APN01, and after obtaining preliminary evidence of its tolerability and preventive efficacy in a mouse model, we pursued development of an aerosol formulation. As a prerequisite to a clinical trial, we evaluated both virus binding activity and enzymatic activity for cleavage of Ang II following aerosolization.

Development of a novel, pan-variant aerosol intervention for COVID-19.

To develop a universal strategy to block SARS-CoV-2 cellular entry and infection represents a central aim for effective COVID-19 therapy. The growing impact of emerging variants of concern increases the urgency for development of effective interventions. Since ACE2 is the critical SARS-CoV-2 receptor and all tested variants bind to ACE2, some even at much increased affinity (see accompanying paper), we hypothesized that aerosol administration of clinical grade soluble human recombinant ACE2 (APN01) will neutralize SARS-CoV-2 in the airways, limit spread of infection in the lung and mitigate lung damage caused by deregulated signaling in the renin-angiotensin (RAS) and Kinin pathways.

Validation of a Stability-Indicating Method for Methylseleno-L-Cysteine (L-SeMC).

Methylseleno-L-cysteine (L-SeMC) is a naturally occurring amino acid analogue used as a general dietary supplement and is being explored as a chemopreventive agent. As a known dietary supplement, L-SeMC is not regulated as a pharmaceutical and there is a paucity of analytical methods available. To address the lack of methodology, a stability-indicating method was developed and validated to evaluate L-SeMC as both the bulk drug and formulated drug product (400 µg Se/capsule).

Prevention of chemically induced urinary bladder cancers by naproxen: protocols to reduce gastric toxicity in humans do not alter preventive efficacy.

The COX inhibitors (NSAID/Coxibs) are a major focus for the chemoprevention of cancer. The COX-2-specific inhibitors have progressed to clinical trials and have shown preventive efficacy in colon and skin cancers. However, they have significant adverse cardiovascular effects.

Preventive effects of NSAIDs, NO-NSAIDs, and NSAIDs plus difluoromethylornithine in a chemically induced urinary bladder cancer model.

Urinary bladder cancer prevention studies were performed with the nonsteroidal anti-inflammatory drugs (NSAID) naproxen (a standard NSAID with a good cardiovascular profile), sulindac, and their nitric oxide (NO) derivatives. In addition, the effects of the ornithine decarboxylase inhibitor, difluoromethylornithine (DFMO), alone or combined with a suboptimal dose of naproxen or sulindac was examined. Agents were evaluated at their human equivalent doses (HED), as well as at lower doses.

Population pharmacokinetic model for cancer chemoprevention with sulindac in healthy subjects.

Sulindac is a prescription-based non-steroidal anti-inflammatory drug (NSAID) that continues to be actively investigated as a candidate cancer chemoprevention agent. To further current understanding of sulindac bioavailability, metabolism, and disposition, we developed a population pharmacokinetic model for the parent compound and its active metabolites, sulindac sulfide, and exisulind. This analysis was based on data from 24 healthy subjects who participated in a bioequivalence study comparing two formulations of sulindac.

Hydrogen sulfide-releasing NSAIDs inhibit the growth of human cancer cells: a general property and evidence of a tissue type-independent effect.

Hydrogen sulfide-releasing non-steroidal anti-inflammatory drugs (HS-NSAIDs) are an emerging novel class of compounds with significant anti-inflammatory properties. They consist of a traditional NSAID to which an H(2)S-releasing moiety is covalently attached. We examined the effects of four different HS-NSAIDs on the growth properties of eleven different human cancer cell lines of six different tissue origins.

Hydrogen sulfide-releasing aspirin suppresses NF-κB signaling in estrogen receptor negative breast cancer cells in vitro and in vivo.

Hormone-dependent estrogen receptor positive (ER+) breast cancers generally respond well to anti-estrogen therapy. Unfortunately, hormone-independent estrogen receptor negative (ER-) breast cancers are aggressive, respond poorly to current treatments and have a poor prognosis. New approaches and targets are needed for the prevention and treatment of ER- breast cancer.

Hydrogen sulfide-releasing aspirin modulates xenobiotic metabolizing enzymes in vitro and in vivo.

The balance between phase-I carcinogen-activating and phase-II detoxifying xenobiotic metabolizing enzymes is critical to determining an individual's risk for cancer. We evaluated the effect of Hydrogen sulfide-releasing aspirin (HS-ASA) on xenobiotic metabolizing enzymes in HT-29 human colon and Hepa 1c1c7 mouse liver adenocarcinoma cells and in Wistar rats. HS-ASA inhibited the growth of HT-29 and Hepa 1c1c7 cells, with an IC(50) of 3.

Synthesis and biological activity of acetyl-protected hydroxybenzyl diethyl phosphates (EHBP) as potential chemotherapeutic agents.

Several acetyl-protected hydroxybenzyl diethyl phosphates (EHBPs) that are capable of forming quinone methide intermediates were synthesized and their cell growth inhibitory properties were evaluated in four different human cancer cell lines. Compounds 1, 1a, and 1b, corresponding to (4-acetyloxybenzyl diethylphosphate), (3-methyl-4-acetyloxybenzyl diethylphosphate), and (3-chloro-4-acetyloxybenzyl diethylphosphate), were significantly more potent than compounds 2 and 3, (2-acetyloxybenzyl diethylphosphate) and (3-acetyloxybenzyl diethylphosphate), respectively. Using HT-29 human colon cancer cells, compounds 1 and 3 increased apoptosis, inhibited proliferation, and caused a G(2)/M block in the cell cycle.

Phase 0 clinical chemoprevention trial of the Akt inhibitor SR13668.

SR13668, an orally active Akt pathway inhibitor, has demonstrated cancer chemopreventive potential in preclinical studies. To accelerate the clinical development of this promising agent, we designed and conducted the first-ever phase 0 chemoprevention trial to evaluate and compare the effects of food and formulation on SR13668 bioavailability. Healthy adult volunteers were randomly assigned to receive a single, 38-mg oral dose of SR13668 in one of five different formulations, with or without food.

Green tea extract-induced lethal toxicity in fasted but not in nonfasted dogs.

Recent chronic toxicity studies performed on green tea extracts in fasted dogs have revealed some unique dose-limiting lethal liver, gastrointestinal, and renal toxicities. Key findings included necrosis of hepatic cells, gastrointestinal epithelia and renal tubules, atrophy of reproductive organs, atrophy and necrosis of hematopoietic tissues, and associated hematological changes. The polyphenol cachetins (a mixture of primarily epigallocatechin gallate [≥55%]; plus up to 10% each of epigallocatechin, epicatechin, and epigallocatechin gallate) appeared to be the causative agents for the observed toxicities because they are the active ingredients of green tea extract studied.

NO-releasing NSAIDs suppress NF-κB signaling in vitro and in vivo through S-nitrosylation.

NO-NSAIDs are promising anticancer drugs, comprising an NSAID, an NO-releasing moiety, and a spacer linking them. Although the effect of NO-NSAIDs on a wide variety of signaling and other cellular mechanisms has been deciphered, a key question remains unanswered, that being the role of NO to the overall biological effect of these agents. It has been shown that NO can directly modify sulfhydryl residues of proteins through S-nitrosylation and induce apoptosis.

Modulation of stress genes expression profile by nitric oxide-releasing aspirin in Jurkat T leukemia cells.

NO-donating aspirin (NO-ASA, para isomer) has been reported to exhibit strong growth inhibitory effect in Jurkat T-acute lymphoblastic leukemia (T-ALL) cells mediated in part by beta-catenin degradation and caspase activation, but the mechanism(s) still remains unclear. In this study, DNA oligoarrays with 263 genes were used to examine the gene expression profiles relating to stress and drug metabolism, and characterize the stress responses at IC(50) and subIC(50) concentrations of p-NO-ASA (20 and 10microM, respectively) in Jurkat T cells. A total of 22 genes related to heat shock response, apoptosis signaling, detoxifiers and Phase II enzymes, and regulators of cell growth were altered in expression by array analysis based on the expression fold change criteria of > or =1.

Chemopreventive efficacy of naproxen and nitric oxide-naproxen in rodent models of colon, urinary bladder, and mammary cancers.

Nonsteroidal anti-inflammatory drugs (NSAID) have been highly effective in preventing colon, urinary bladder, and skin cancer preclinically, and also in clinical trials of colon adenoma formation. However, certain NSAIDs cause gastrointestinal ulceration and may increase cardiovascular events. Naproxen seems to cause the lowest cardiovascular events of the common NSAIDs other than aspirin.

Label-free global serum proteomic profiling reveals novel celecoxib-modulated proteins in familial adenomatous polyposis patients.

Celecoxib, a selective inhibitor of cyclooxygenase-2 (Cox-2), was efficacious in clinical prevention trials of patients with familial adenomatous polyposis (FAP) and sporadic colorectal cancer. To identify as yet poorly defined molecular determinants of celecoxib efficacy, a multidimensional serum fractionation approach was used coupled with nanospray tandem mass spectrometry to perform label-free global proteomic profiling of serum samples from the FAP/celecoxib prevention trial. Subsequently, the application of an algorithm for large-scale biomarker discovery on comparative serum proteomic profiles of pre- and post-celecoxib treatment samples identified 83 potentially celecoxib-responsive proteins from various cellular compartments, biological processes and molecular functions.

Lack of efficacy of the statins atorvastatin and lovastatin in rodent mammary carcinogenesis.

The statins are highly effective in lowering cholesterol by inhibiting 3-hydroxy-3-methylglutaryl CoA reductase. Recently, there has been conflicting epidemiologic data indicating that statins decrease the incidence of certain types of cancer, including breast cancer. Atorvastatin and lovastatin, statins with different lipophicilities, were administered in diet either as single agents or in combination with suboptimal doses of tamoxifen or the retinoid X receptor agonist bexarotene were evaluated for prevention of estrogen receptor-positive mammary cancers induced in the rat with methylnitrosourea.

Comparative bioavailability of sulindac in capsule and tablet formulations.

The cyclooxygenase (COX)-2 enzyme appears to be an important target for cancer chemoprevention. Given the recent emergence of potentially serious cardiovascular toxicity associated with selective COX-2 inhibitors, nonsteroidal antiinflammatory drugs (NSAIDs), which inhibit both COX-1 and COX-2, have received renewed attention as candidate chemoprevention agents. Sulindac has shown consistent chemopreventive potential in preclinical studies as well as in a limited number of clinical trials reported to date.

Comparison of eyeblink conditioning in patients with superior and posterior inferior cerebellar lesions.

The aim of the present study was to compare eyeblink conditioning in cerebellar patients with lesions including the territory of the superior cerebellar artery (SCA) and in patients with lesions restricted to the territory of the posterior inferior cerebellar artery (PICA). The cerebellar areas known to be most critical in eyeblink conditioning based on animal data (i.e.

Human-bacteria nitric oxide cycles in HIV-1 infection.

The human intestinal tract harbors a complex microbiotic environment containing commensal bacteria and immunocompetent mucosal cells. There is considerable communication between the bacteria and host cells through dietary constituents and metabolic cycles. We propose that in the pathogenesis of acquired immunodeficiency syndrome (AIDS), the human immunodeficiency virus-1 (HIV-1) triggers a change in a coupled transorganism (human-bacteria) nitric oxide interchange cycle, that may influence the biosynthesis and recycling of nitric oxide (NO) in AIDS patients.

Motor deficits cannot explain impaired cognitive associative learning in cerebellar patients.

There is a strong evidence that the cerebellum is involved in associative motor learning. The exact role of the cerebellum in motor learning, and whether it is involved in cognitive learning processes too, are still controversially discussed topics. A common problem of assessing cognitive capabilities of cerebellar patients is the existence of additional motor demands in all cognitive tests.

Structural requirements for arachidonylethanolamide interaction with CB1 and CB2 cannabinoid receptors: pharmacology of the carbonyl and ethanolamide groups.

Analogs of arachidonylethanolamide (anandamide) were prepared to investigate the structural requirements for ligand binding to and activation of the CB1 and CB2 cannabinoid receptors. The importance of the presence and the placement of the carbonyl was examined with analogs lacking the carbonyl or with the carbonyl amide order reversed. The presence and location of the carbonyl is essential for high-affinity binding to both cannabinoid receptor subtypes, and for determination of signal transduction via G-proteins.

Cerebrodiene, arachidonyl-ethanolamide, and hybrid structures: potential for interaction with brain cannabinoid receptors.

Cerebrodiene (cis-9, 10-octadecenoamide) was recently isolated from cerebral fluid of sleep-deprived cats and shown to induce sleep in rats. Because this lipid amide is related to arachidonylethanolamide (AEA), and because AEA binds to the cannabinoid receptor with high affinity, we investigated the binding affinity of cerebrodiene and some analogs to the cannabinoid receptor. In addition, we tested the ability of these compounds to act as cannabinoid receptor agonists by determining GTP gamma S binding.