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1.
Pharmaceutics ; 15(7)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37513977

ABSTRACT

Reperfusion injuries after a period of cardiac ischemia are known to lead to pathological modifications or even death. Among the different therapeutic options proposed, adenosine, a small molecule with platelet anti-aggregate and anti-inflammatory properties, has shown encouraging results in clinical trials. However, its clinical use is severely limited because of its very short half-life in the bloodstream. To overcome this limitation, we have proposed a strategy to encapsulate adenosine in squalene-based nanoparticles (NPs), a biocompatible and biodegradable lipid. Thus, the aim of this study was to assess, whether squalene-based nanoparticles loaded with adenosine (SQAd NPs) were cardioprotective in a preclinical cardiac ischemia/reperfusion model. Obtained SQAd NPs were characterized in depth and further evaluated in vitro. The NPs were formulated with a size of about 90 nm and remained stable up to 14 days at both 4 °C and room temperature. Moreover, these NPs did not show any signs of toxicity, neither on HL-1, H9c2 cardiac cell lines, nor on human PBMC and, further retained their inhibitory platelet aggregation properties. In a mouse model with experimental cardiac ischemia-reperfusion, treatment with SQAd NPs showed a reduction of the area at risk, as well as of the infarct area, although not statistically significant. However, we noted a significant reduction of apoptotic cells on cardiac tissue from animals treated with the NPs. Further studies would be interesting to understand how and through which mechanisms these nanoparticles act on cardiac cells.

2.
Chemosensors (Basel) ; 10(2)2022 Feb.
Article in English | MEDLINE | ID: mdl-36540572

ABSTRACT

Antibodies produced in response to adaptive immunity provide a receptor with multiple sites for binding to a distinct epitope of an antigen. Determining antibody levels to specific antigens has important clinical applications in assessing immune status or deficiency, monitoring infectious or autoimmune diseases, and diagnosing allergies. Leveraging that a specific antibody will bind to a distinct small peptide epitope without requiring the entire antigen to be present, we demonstrate in this work a proof-of-concept assay to detect the presence of an antibody by using peptide epitopes linked to an amphiphile to generate a vesicle-based sensing system. By affording multiple copies of the epitope site on the vesicle, we revealed that the vesicles visibly aggregate in response to an antibody specific for that epitope due to multivalent binding provided by the antibody. We also uncovered the role of peptide surface density in providing accessible epitopes on the vesicles for antibody binding. In summary, using a peptide derived from the coat protein of human influenza virus directly linked to a diacetylene-containing amphiphile afforded peptide-laden vesicles that proved capable of detecting the presence of antibodies specific for human influenza hemagglutinin.

3.
Acute Crit Care ; 37(3): 295-302, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35791659

ABSTRACT

BACKGROUND: To explore the feasibility, safety, and potential benefits of administration of the anabolic steroid nandrolone to patients in the recovery phase from critical illness weakness. METHODS: In this phase II, double blind, randomized, controlled trial, adult critically ill patients admitted to one of two tertiary Intensive Care Units in Western Australia for longer than 7 days with significant weakness were enrolled. Patients received nandrolone (200 mg males, 100 mg females) intramuscularly or placebo weekly for up to 3 weeks in addition to standard care. The primary outcome measures were improvement in grip strength, Medical Research Council muscle strength sum score, and functional activity level (Chelsea critical care assessment tool [CPAx]). RESULTS: A total of 22 patients was enrolled between September 2017 and May 2019. No significant adverse events were detected. Median grip strength change was non-significantly greater in the nandrolone group (8.5 vs. 13.0, P=0.185), while hospital length of stay (36 vs. 26 days, P=0.023) and duration of mechanical ventilation (377 vs. 168, P=0.032) were lower. The discharge CPAx and intensive care unit mobility scores were higher in the nandrolone group, although there was no difference in the change in CPAx score (17.0 vs. 17.7, P=0.865). There were no changes in ultrasound-detected muscle thickness between the two groups. CONCLUSIONS: In patients with prolonged critical illness, nandrolone appears to be safe. However, a larger study, potentially combined with resistance exercise, is needed to definitively address the potential benefits of nandrolone.

4.
Pharmaceutics ; 13(1)2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33445646

ABSTRACT

Cyclosporin A (CsA) is a molecule with well-known immunosuppressive properties. As it also acts on the opening of mitochondrial permeability transition pore (mPTP), CsA has been evaluated for ischemic heart diseases (IHD). However, its distribution throughout the body and its physicochemical characteristics strongly limit the use of CsA for intravenous administration. In this context, nanoparticles (NPs) have emerged as an opportunity to circumvent the above-mentioned limitations. We have developed in our laboratory an innovative nanoformulation based on the covalent bond between squalene (Sq) and cyclosporin A to avoid burst release phenomena and increase drug loading. After a thorough characterization of the bioconjugate, we proceeded with a nanoprecipitation in aqueous medium in order to obtain SqCsA NPs of well-defined size. The SqCsA NPs were further characterized using dynamic light scattering (DLS), cryogenic transmission electron microscopy (cryoTEM), and high-performance liquid chromatography (HPLC), and their cytotoxicity was evaluated. As the goal is to employ them for IHD, we evaluated the cardioprotective capacity on two cardiac cell lines. A strong cardioprotective effect was observed on cardiomyoblasts subjected to experimental hypoxia/reoxygenation. Further research is needed in order to understand the mechanisms of action of SqCsA NPs in cells. This new formulation of CsA could pave the way for possible medical application.

5.
Pharmacy (Basel) ; 8(4)2020 Oct 05.
Article in English | MEDLINE | ID: mdl-33027982

ABSTRACT

Preconception health refers to health before pregnancy and involves addressing risk factors that can negatively impact either a patient or future pregnancy. Pharmacists can play an essential role in screening for and managing patients' risk factors to optimize pregnancy outcomes. The primary objective of this study is to determine whether preconception health screenings in community pharmacy settings identify opportunities for preconception health services, particularly pharmacy-based interventions. The secondary objectives are to describe the preconception health status of community pharmacy patients and their interest in receiving preconception care services by a clinical pharmacist in a community pharmacy setting. Two independent pharmacies conducted a pilot project where people were invited to complete a health screening form that evaluated their preconception health. Participants received a personalized health report with an invitation to meet with the clinical pharmacist for services related to identified opportunities, such as contraception and immunizations. Retrospective analysis was conducted for data collected from 43 women during the patient screening effort in three community pharmacy settings (two independent community pharmacy locations and one neighborhood pharmacy outreach event). Nearly all participants (n = 42, 98%) had at least one opportunity identified to receive preconception care services, with the majority related to their alcohol use (60%). A majority of participants (56%) indicated an interest in learning more about preconception services offered at the pharmacy, but only 19% wanted to schedule an appointment with a pharmacist. Thus, there is an apparent need and opportunity for utilization of preconception health services at the pharmacy.

6.
Mol Pharm ; 17(5): 1527-1537, 2020 05 04.
Article in English | MEDLINE | ID: mdl-32212738

ABSTRACT

Compared with the significant number of studies reporting altered abundance and function of drug transporters at the blood-brain barrier (BBB) in Alzheimer's disease (AD), the impact of AD on the abundance of intestinal drug transporters and the subsequent effects on oral drug absorption have received little attention. We have reported the altered abundance of some small intestinal drug transporters in a familial mouse model of AD; however, whether this leads to altered oral drug absorption is unknown. The current study examined plasma concentrations of caffeine and diazepam (markers for transcellular passive transport), digoxin (P-glycoprotein substrate), and valsartan (multidrug resistance-associated protein 2 substrate) following oral administration to 8-10 month old female wild-type (WT) and APPswe/PSEN1dE9 (APP/PS1) transgenic mice, a commonly used mouse model of familial AD. The plasma exposure of valsartan and digoxin was significantly (p < 0.05) lower in APP/PS1 animals compared with WT mice, whereas the plasma concentrations of the passive transcellular markers caffeine and diazepam did not significantly differ between the two genotypes. To assess whether the reduced oral absorption of valsartan and digoxin was due to decreased intestinal transport, the ex vivo transport of the previously mentioned drugs and mannitol (a marker of paracellular transport) across the jejunum of WT and APP/PS1 mice was assessed over 120 min. In line with the in vivo absorption studies, the permeability of caffeine and diazepam did not significantly differ between WT and APP/PS1 mice. The permeability of 3H-digoxin through the APP/PS1 mouse jejunum was lower than that measured through the WT jejunum; the average amount (relative to dose applied) permeating the tissue over 120 min was 0.22 ± 0.11% (mean ± SD) for the APP/PS1 jejunum and 0.85 ± 0.3% for the WT jejunum. A 1.9-fold reduction in the average amount of valsartan permeating the jejunum of APP/PS1 mice relative to that of WT mice was also detected. Although no apparent morphological alterations were observed in the jejunal tissue of APP/PS1 mice, the permeability of 14C-mannitol across the jejunum from APP/PS1 mice was lower than that across the WT jejunum (Papp= 10.7 ± 3.7 × 10-6 and 6.0 ± 3.4 × 10-6 cm/s, respectively), suggesting tightened paracellular junctions in APP/PS1 mice. These studies are the first to demonstrate, in APP/PS1 mice, reduced intestinal permeability and the absorption of drugs commonly prescribed to people with AD for their comorbidities. If these findings translate to people with AD, then modified dosing regimens may be necessary for selected drugs to ensure that their plasma concentrations remain in the effective range.


Subject(s)
Alzheimer Disease/metabolism , Intestinal Absorption , Intestinal Mucosa/metabolism , Administration, Oral , Animals , Caffeine/pharmacokinetics , Diazepam/pharmacokinetics , Digoxin/pharmacokinetics , Disease Models, Animal , Female , Jejunum/metabolism , Mice , Permeability , Valsartan/pharmacokinetics
7.
Nucl Med Biol ; 80-81: 13-23, 2020.
Article in English | MEDLINE | ID: mdl-31759313

ABSTRACT

OBJECTIVE: The objectives of the present work were to optimize and validate the synthesis and stability of 14(R,S)-[18F]fluoro-6-thia-heptadecanoic acid ([18F]FTHA) and 16-[18F]fluoro-4-thia-palmitic acid ([18F]FTP) under cGMP conditions for clinical applications. METHODS: Benzyl-14-(R,S)-tosyloxy-6-thiaheptadecanoate and methyl 16-bromo-4-thia-palmitate were used as precursors for the synthesis of [18F]FTHA and [18F]FTP, respectively. For comparison, a fatty acid analog lacking a thia-substitution, 16-[18F]fluoro-palmitic acid ([18F]FP), was synthesized from the precursor methyl 16-bromo-palmitate. A standard nucleophilic reaction using cryptand (Kryptofix/K222, 8.1 mg), potassium carbonate (K2CO3, 4.0 mg) and 18F-fluoride were employed for the 18F-labeling and potassium hydroxide (0.8 M) was used for the post-labeling ester hydrolysis. The final products were purified via reverse phase semi-preparative HPLC and concentrated via trap and release on a C-18 plus solid phase extraction cartridge. The radiochemical purities of the [18F]fluorothia fatty acids and [18F]FP were examined over a period of 4 h post-synthesis using an analytical HPLC. All the syntheses were optimized in an automated TRACERlab FX-N Pro synthesizer. Liquid chromatography mass spectrometry (LCMS) and high resolution mass spectrometry (HRMS) was employed to study the identity and nature of side products formed during radiosynthesis and as a consequence of post-synthesis radiation induced oxidation. RESULTS: Radiosyntheses of [18F]FTHA, [18F]FTP and [18F]FP were achieved in moderate (8-20% uncorrected) yields. However, it was observed that the HPLC-purified [18F]fluorothia fatty acids, [18F]FTHA and [18F]FTP at higher radioactivity concentrations (>1.11 GBq/mL, 30 mCi/mL) underwent formation of 18F-labeled side products over time but [18F]FP (lacking a sulfur heteroatom) remained stable up to 4 h post-synthesis. Various radiation protectors like ethanol and ascorbic acid were examined to minimize the formation of side products formed during [18F]FTHA and [18F]FTP synthesis but showed only limited to no effect. Analysis of the side products by LCMS showed formation of sulfoxides of both [18F]FTHA and [18F]FTP. The identity of the sulfoxide side product was further confirmed by synthesizing a non-radioactive reference standard of the sulfoxide analog of FTP and matching retention times on HPLC and molecular ion peaks on LC/HRMS. Radiation-induced oxidation of the sulfur heteroatom was mitigated by dilution of product with isotonic saline to reduce the radioactivity concentration to <0.518 GBq/mL (14 mCi/mL). CONCLUSIONS: Successful automated synthesis of [18F]fluorothia fatty acids were carried out in cGMP facility for their routine production and clinical applications. Instability of [18F]fluorothia fatty acids were observed at radioactivity concentrations exceeding 1.11 GBq/mL (30 mCi/mL) but mitigated through dilution of the product to <0.518 GBq/mL (14 mCi/mL). The identities of the side products formed were established as the sulfoxides of the respective thia fatty acids caused by radiation-induced oxidation of the sulfur heteroatom.


Subject(s)
Fatty Acids/chemistry , Fluorine Radioisotopes/chemistry , Radiochemistry/methods , Oxidation-Reduction
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