Current therapeutic treatment options for osteoarthritis entail significant safety concerns. A novel ropivacaine crystalline microsuspension for bolus intra-articular (IA) delivery was thus developed and studied in a peptidoglycan polysaccharide (PGPS)-induced ankle swelling rat model. Compared with celecoxib controls, both oral and IA, ropivacaine IA treatment resulted in a significant reduction of pain upon successive PGPS reactivation, as demonstrated in two different pain models, gait analysis and incapacitance testing. The reduction in pain was attended by a significant reduction in histological inflammation, which in turn was accompanied by significant reductions in the cytokines IL-18 and IL-1?. This may have been due to inhibition of substance P, which was also significantly reduced. Pharmacokinetic analysis indicated that the analgesic effects outlasted measurable ropivacaine levels in either blood or tissue. The results are discussed in the context of pharmacologic mechanisms both of local anesthetics as well as inflammatory arthritis.
Abstract Objective: The purpose of this work was to prepare a stable paclitaxel nanosuspension and test it for potential use as a targeted chemotherapeutic. Different particle coatings were employed to assess their impact on cellular uptake in vitro. In vivo work was then performed to demonstrate efficacy in tumor-bearing mouse models. Materials and method: Paclitaxel nanosuspensions were prepared using a homogenization process and coated with excipients. Surface charge was measured by zeta potential, potency by high-performance liquid chromatography, and solubility using an in-line UV probe. Cellular uptake studies were performed via flow cytometry. In vivo experiments were performed to determine residence time, maximum tolerated dose, and the efficacy of paclitaxel nanosuspensions (Paclitaxel-NS). Results: A stable paclitaxel nanosuspension was prepared and coated with various excipients. Studies in mice showed that the nanosuspension was well-tolerated and at least as effective as the IV Taxol control in prolonging mouse survival in a head and neck cancer model as well as an ovarian cancer model with a lower overall drug dose than the traditional IV administration route. Conclusions: The paclitaxel nanosuspension is suitable for cellular uptake. The nanosuspension was effective in prolonging life in two separate xenograft orthotopic murine cancer models through two separate routes of administration.
Limitations inherent to antiretroviral therapy (ART) in its pharmacokinetic properties remain despite over 15 years of broad use. Our laboratory has pioneered a means to improve ART delivery through monocyte-macrophage carriage of nanoformulated drug-encapsulated particles (nanoART). To this end, our prior works sought to optimize nanoART size, charge, and physical properties for cell uptake and antiretroviral activities. To test the functional consequences of indinavir, ritonavir, and efavirenz formulations we investigated relationships between human monocyte and macrophage cytotoxicities and nanoART dose, size, surfactant, and preparation. Wet-milled particles were more cytotoxic to monocytes-macrophages than those prepared by homogenization; with concurrent induction of tumor necrosis factor-alpha. Interestingly, pure suspensions of indinavir and ritonavir at 0.5 mM, and efavirenz at 0.1 mM and 0.5 mM also proved cytotoxic. Individual surfactants and formulated fluconazole neither affected cell function or viability. Although nanoART did not alter brain tight junction proteins ZO-2 and occludin, 0. 5mM ritonavir formulations did alter brain transendothelial electric resistance. These results underscore the potential importance of evaluating the physicochemical and functional properties of nanoART before human evaluations.
This article addresses the identification and quantification of the chemical species resulting in resonances at 2.17 and 2.25 ppm in the (1)H nuclear magnetic resonance (NMR) spectrum of pharmaceutical-grade heparin sodium. The NMR signals in question were first confirmed to arise from chemical moieties covalently attached to the heparin molecule through NMR diffusion experiments as well as chemical treatment of heparin active pharmaceutical ingredient (API) containing the resonances. The material responsible for the extra NMR signals was then demonstrated by NMR spiking studies to be something other than oversulfated chondroitin sulfate and was finally identified as an O-acetylation product of heparin through (13)C labeling experiments with subsequent NMR analysis. The extent of O-acetylation was quantified using three orthogonal techniques: (1)H NMR, ion chromatography, and headspace gas chromatography/mass spectrometry. The results of this work showed good agreement between the three quantitative methods developed to analyze the signals in the United States Pharmacopeia-specified region of 2.12-3.00 ppm for heparin API.
Previously, it was observed that a nanosuspension formulation of itraconazole was more efficacious and yet less acutely toxic in rats as compared with the conventional solution formulation, SPORANOX (itraconazole) Injection. The present study compares the two formulations with respect to specifically myocardial contractility in conscious dogs. Motivation for doing so is highlighted by the black-box warning in the package insert for SPORANOX (itraconazole) Injection, which warns of negative inotropic effects. Conscious dogs, instrumented with a high-fidelity pressure transducer in the left ventricle, were placed in a sling for dosing and cardiac monitoring. Test and control articles were administered intravenously via a peripheral vein, and left ventricular parameters were measured continuously through 60 min from the start of dosing. As expected, SPORANOX (itraconazole) Injection caused a significant reduction in myocardial contractility as determined by the contractility index. In contrast, the itraconazole nanosuspension administered at twice the dose and at twice the rate of infusion did not result in significant changes in myocardial contractility. A novel formulation technology applied to itraconazole completely prevented the negative inotropic effect observed in conscious dogs as compared with SPORANOX (itraconazole) Injection.
We posit that improvements in pharmacokinetics and biodistributions of antiretroviral therapies (ART) for human immunodeficiency virus type one-infected people can be achieved through nanoformulationed drug delivery systems. To this end, we manufactured nanoparticles of atazanavir, efavirenz, and ritonavir (termed nanoART) and treated human monocyte-derived macrophages (MDM) in combination therapies to assess antiretroviral responses. This resulted in improved drug uptake, release, and antiretroviral efficacy over monotherapy. MDM rapidly, within minutes, ingested nanoART combinations, at equal or similar rates, as individual formulations. Combination nanoART ingested by MDM facilitated individual drug release from 15 to >20 days. These findings are noteworthy as a nanoART cell-mediated drug delivery provides a means to deliver therapeutics to viral sanctuaries, such as the central nervous system during progressive human immunodeficiency virus type one infection. The work brings us yet another step closer to realizing the utility of nanoART for virus-infected people.
Factors limiting the efficacy of conventional antiretroviral therapy for HIV-1 infection include treatment adherence, pharmacokinetics and penetration into viral sanctuaries. These affect the rate of viral mutation and drug resistance. In attempts to bypass such limitations, nanoparticles containing ritonavir, indinavir and efavirenz (described as nanoART) were manufactured to assess macrophage-based drug delivery.
Antiretroviral therapy (ART) shows variable blood-brain barrier penetration. This may affect the development of neurological complications of HIV infection. In attempts to attenuate viral growth for the nervous system, cell-based nanoformulations were developed with the focus on improving drug pharmacokinetics. We reasoned that ART carriage could be facilitated within blood-borne macrophages traveling across the blood-brain barrier. To test this idea, an HIV-1 encephalitis (HIVE) rodent model was used where HIV-1-infected human monocyte-derived macrophages were stereotactically injected into the subcortex of severe combined immunodeficient mice. ART was prepared using indinavir (IDV) nanoparticles (NP, nanoART) loaded into murine bone marrow macrophages (BMM, IDV-NP-BMM) after ex vivo cultivation. IDV-NP-BMM was administered i.v. to mice resulting in continuous IDV release for 14 days. Rhodamine-labeled IDV-NP was readily observed in areas of HIVE and specifically in brain subregions with active astrogliosis, microgliosis, and neuronal loss. IDV-NP-BMM treatment led to robust IDV levels and reduced HIV-1 replication in HIVE brain regions. We conclude that nanoART targeting to diseased brain through macrophage carriage is possible and can be considered in developmental therapeutics for HIV-associated neurological disease.
We posit that the same mononuclear phagocytes (MP) that serve as target cells and vehicles for a host of microbial infections can be used to improve diagnostics and drug delivery. We also theorize that physical and biological processes such as particle shape, size, coating and opsonization that affect MP clearance of debris and microbes can be harnessed to facilitate uptake of nanoparticles (NP) and tissue delivery.
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