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1.
Transl Med Commun ; 6(1): 3, 2021.
Article in English | MEDLINE | ID: mdl-33521322

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has profoundly affected the lives of millions of people. To date, there is no approved vaccine or specific drug to prevent or treat COVID-19, while the infection is globally spreading at an alarming rate. Because the development of effective vaccines or novel drugs could take several months (if not years), repurposing existing drugs is considered a more efficient strategy that could save lives now. Statins constitute a class of lipid-lowering drugs with proven safety profiles and various known beneficial pleiotropic effects. Our previous investigations showed that statins have antiviral effects and are involved in the process of wound healing in the lung. This triggered us to evaluate if statin use reduces mortality in COVID-19 patients. RESULTS: After initial recruitment of 459 patients with COVID-19 (Shiraz province, Iran) and careful consideration of the exclusion criteria, a total of 150 patients, of which 75 received statins, were included in our retrospective study. Cox proportional-hazards regression models were used to estimate the association between statin use and rate of death. After propensity score matching, we found that statin use appeared to be associated with a lower risk of morbidity [HR = 0.85, 95% CI = (0.02, 3.93), P = 0.762] and lower risk of death [(HR = 0.76; 95% CI = (0.16, 3.72), P = 0.735)]; however, these associations did not reach statistical significance. Furthermore, statin use reduced the chance of being subjected to mechanical ventilation [OR = 0.96, 95% CI = (0.61-2.99), P = 0.942] and patients on statins showed a more normal computed tomography (CT) scan result [OR = 0.41, 95% CI = (0.07-2.33), P = 0.312]. CONCLUSIONS: Although we could not demonstrate a significant association between statin use and a reduction in mortality in patients with COVID19, we do feel that our results are promising and of clinical relevance and warrant the need for prospective randomized controlled trials and extensive retrospective studies to further evaluate and validate the potential beneficial effects of statin treatment on clinical symptoms and mortality rates associated with COVID-19.

2.
Virulence ; 11(1): 805-810, 2020 12.
Article in English | MEDLINE | ID: mdl-32567972

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak resulted in 5,993,317 confirmed cases worldwide with 365,394 confirmed deaths (as of May 29th, 2020, WHO). The molecular mechanism of virus infection and spread in the body is not yet disclosed, but studies on other betacoronaviruses show that, upon cell infection, these viruses inhibit macroautophagy/autophagy flux and cause the accumulation of autophagosomes. No drug has yet been approved for the treatment of SARS-CoV-2 infection; however, preclinical investigations suggested repurposing of several FDA-approved drugs for clinical trials. Half of these drugs are modulators of the autophagy pathway. Unexpectedly, instead of acting by directly antagonizing the effects of viruses, these drugs appear to function by suppressing autophagy flux. Based on the established cross-talk between autophagy and apoptosis, we speculate that over-accumulation of autophagosomes activates an apoptotic pathway that results in apoptotic death of the infected cells and disrupts the virus replication cycle. However, administration of the suggested drugs are associated with severe adverse effects due to their off-target accumulation. Nanoparticle targeting of autophagy at the sites of interest could be a powerful tool to efficiently overcome SARS-CoV-2 infection while avoiding the common adverse effects of these drugs.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Autophagy , COVID-19 , Humans , Pandemics , SARS-CoV-2
3.
Eur J Pharm Biopharm ; 118: 62-67, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27888144

ABSTRACT

The influence of vitamin D3 and its metabolites calcifediol (25(OH)D) and calcitriol on immune regulation and inflammation is well described, and raises the question of potential benefit against bacterial infections. In the current study, 25(OH)D was encapsulated in liposomes to enable aerosolisation, and tested for the ability to prevent pulmonary infection by Pseudomonas aeruginosa. Prepared 25(OH)D-loaded liposomes were nanosized and monodisperse, with a negative surface charge and a 25(OH)D entrapment efficiency of approximately 23%. Jet nebulisation of liposomes was seen to yield an aerosol suitable for tracheo-bronchial deposition. Interestingly, 25(OH)D in either liposomes or ethanolic solution had no effect on the release of the proinflammatory cytokine KC from Pseudomonas-infected murine epithelial cells (LA-4); treatment of infected, human bronchial 16-HBE cells with 25(OH)D liposomes however resulted in a significant reduction in bacterial survival. Together with the importance of selecting an application-appropriate in vitro model, the current study illustrates the feasibility and practicality of employing liposomes as a means to achieve 25(OH)D lung deposition. 25(OH)D-loaded liposomes further demonstrated promising effects regarding prevention of Pseudomonas infection in human bronchial epithelial cells.


Subject(s)
Calcifediol/administration & dosage , Cystic Fibrosis/drug therapy , Immunologic Factors/administration & dosage , Pseudomonas Infections/drug therapy , Pseudomonas aeruginosa/drug effects , Respiratory Tract Infections/drug therapy , Administration, Inhalation , Animals , Bronchi/cytology , Calcifediol/therapeutic use , Cell Line , Cystic Fibrosis/immunology , Cystic Fibrosis/microbiology , Cytokines/metabolism , Epithelial Cells , Humans , Immunologic Factors/therapeutic use , Liposomes , Mice , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/isolation & purification , Respiratory Tract Infections/immunology , Respiratory Tract Infections/microbiology
4.
J Control Release ; 220(Pt A): 414-424, 2015 Dec 28.
Article in English | MEDLINE | ID: mdl-26522071

ABSTRACT

Intracellular bacteria invade mammalian cells to establish an infectious niche. The current work models adhesion and subsequent internalization strategy of pathogenic bacteria into mammalian cells to design a bacteriomimetic bioinvasive delivery system. We report on the surface functionalization of liposomes with a C-terminal fragment of invasin (InvA497), an invasion factor in the outer membrane of Yersinia pseudotuberculosis. InvA497-functionalized liposomes adhere to mammalian epithelial HEp-2 cell line at different infection stages with a significantly higher efficiency than liposomes functionalized with bovine serum albumin. Covalent attachment of InvA497 results in higher cellular adhesion than liposomes with physically adsorbed InvA497 with non-specific surface protein alignment. Uptake studies in HEp-2 cells indicate active internalization of InvA497-functionalized liposomes via ß1-integrin receptor-mediated uptake mechanism mimicking the natural invasion strategy of Y. pseudotuberculosis. Uptake studies in Caco-2 cells at different polarization states demonstrate specific targeting of the InvA497-functionalized liposomes to less polarized cells reflecting the status of inflamed cells. Moreover, when loaded with the anti-infective agent gentamicin and applied to HEp-2 cells infected with Y. pseudotuberculosis, InvA497-functionalized liposomes are able to significantly reduce the infection load relative to non-functionalized drug-loaded liposomes. This indicates a promising application of such a bacteriomimetic system for drug delivery to intracellular compartments.


Subject(s)
Adhesins, Bacterial/metabolism , Anti-Bacterial Agents/metabolism , Cell Membrane/metabolism , Drug Carriers , Epithelial Cells/metabolism , Gentamicins/metabolism , Nanoparticles , Peptide Fragments/metabolism , Yersinia pseudotuberculosis/drug effects , Adhesins, Bacterial/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bacterial Adhesion , Bacterial Load/drug effects , Biological Transport , Biomimetics , Caco-2 Cells , Cell Membrane/drug effects , Cell Membrane/microbiology , Epithelial Cells/drug effects , Epithelial Cells/microbiology , Gentamicins/chemistry , Gentamicins/pharmacology , Humans , Integrin beta1 , Kinetics , Liposomes , Nanotechnology , Peptide Fragments/chemistry , Yersinia pseudotuberculosis/metabolism , Yersinia pseudotuberculosis/pathogenicity
5.
Pharm Res ; 27(10): 2106-18, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20652728

ABSTRACT

PURPOSE: Evaluating the potentials of particulate delivery systems in topical drug delivery. METHODS: Polymethacrylate microparticles (MPs) incorporating verapamil hydrochloride (VRP) as a model hydrophilic drug with potential topical clinical uses, using Eudragit RS100 and Eudragit L100 were prepared for the formulation of a composite topical gel. The effect of initial drug loading, polymer composition, particularly the proportion of Eudragit L100 as an interacting polymer component and the HLB of the dispersing agent on MPs characteristics was investigated. A test MPs formulation was incorporated in gel and evaluated for drug release and human skin permeation. RESULTS: MPs showed high % incorporation efficiency and % yield. Composition of the hybrid polymer matrix was a main determinant of MPs characteristics, particularly drug release. Factors known to influence drug release such as MPs size and high drug solubility were outweighed by strong VRP-Eudragit L100 interaction. The developed MPs gel showed controlled VRP release and reduced skin retention compared to a free drug gel. CONCLUSION: Topical drug delivery and skin retention could be modulated using particulate delivery systems. From a practical standpoint, the VRP gel developed may offer advantage in a range of dermatological conditions, in response to the growing off-label topical use of VRP.


Subject(s)
Acrylic Resins/chemistry , Calcium Channel Blockers/administration & dosage , Drug Carriers/chemistry , Polymethacrylic Acids/chemistry , Skin/metabolism , Verapamil/administration & dosage , Administration, Topical , Adult , Calorimetry, Differential Scanning , Delayed-Action Preparations , Female , Gels , Humans , In Vitro Techniques , Microscopy, Electron, Scanning , Middle Aged , Particle Size , Skin Absorption/drug effects , Solubility , Surface Properties
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