Amphotericin B-copper(II) complex shows improved therapeutic index in vitro

2017 ◽  
Vol 97 ◽  
pp. 9-21 ◽  
Author(s):  
Barbara Chudzik ◽  
Grzegorz Czernel ◽  
Arkadiusz Miaskowski ◽  
Mariusz Gagoś
Keyword(s):  
Amphotericin B ◽  
Therapeutic Index

scholarly journals In Vitro and In Vivo Antifungal Activity of Amphotericin B Lipid Complex: Are Phospholipases Important?

1998 ◽  
Vol 42 (4) ◽  
pp. 767-771 ◽  
Author(s):  
Christine E. Swenson ◽  
Walter R. Perkins ◽  
Patricia Roberts ◽  
Imran Ahmad ◽  
Rachel Stevens ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Amphotericin B ◽  
Vascular Tissue ◽  
Therapeutic Index ◽  
Test Material ◽  
Lipid Complex ◽  
In Vitro Susceptibility ◽  
Amphotericin B Lipid Complex

ABSTRACT Amphotericin B lipid complex for injection (ABLC) is a suspension of amphotericin B complexed with the lipidsl-α-dimyristoylphosphatidylcholine (DMPC) andl-α-dimyristoylphosphatidylglycerol. ABLC is less toxic than amphotericin B deoxycholate (AmB-d), while it maintains the antifungal activity of AmB-d. Active amphotericin B can be released from ABLC by exogenously added (snake venom, bacteria, orCandida-derived) phospholipases or by phospholipases derived from activated mammalian vascular tissue (rat arteries). Such extracellular phospholipases are capable of hydrolyzing the major lipid in ABLC. Mutants of C. albicans that were resistant to ABLC but not AmB-d in vitro were deficient in extracellular phospholipase activity, as measured on egg yolk agar or as measured by their ability to hydrolyze DMPC in ABLC. ABLC was nevertheless effective in the treatment of experimental murine infections produced by these mutants. Isolates of Aspergillus species, apparently resistant to ABLC in vitro (but susceptible to AmB-d), were also susceptible to ABLC in vivo. We suggest that routine in vitro susceptibility tests with ABLC itself as the test material may not accurately predict the in vivo activity of ABLC and that the enhanced therapeutic index of ABLC relative to that of AmB-d in vivo may be due, in part, to the selective release of active amphotericin B from the complex at sites of fungal infection through the action of fungal or host cell-derived phospholipases.

scholarly journals Carrier effects on biological activity of amphotericin B.

1996 ◽  
Vol 9 (4) ◽  
pp. 512-531 ◽  
Author(s):  
J Brajtburg ◽  
J Bolard
Keyword(s):  
Amphotericin B ◽  
Mammalian Cells ◽  
Fungal Infections ◽  
Therapeutic Index ◽  
Fungal Cell ◽  
Drug Of Choice ◽  
Higher Doses ◽  
Lipid Formulations

Amphotericin B (AmB), the drug of choice for the treatment of most systemic fungal infections, is marketed under the trademark Fungizone, as an AmB-deoxycholate complex suitable for intravenous administration. The association between AmB and deoxycholate is relatively weak; therefore, dissociation occurs in the blood. The drug itself interacts with both mammalian and fungal cell membranes to damage cells, but the greater susceptibility of fungal cells to its effects forms the basis for its clinical usefulness. The ability of the drug to form stable complexes with lipids has allowed the development of new formulations of AmB based on this property. Several lipid-based formulations of the drug which are more selective in damaging fungal or parasitic cells than mammalian cells and some of which also have a better therapeutic index than Fungizone have been developed. In vitro investigations have led to the conclusion that the increase in selectivity observed is due to the selective transfer of AmB from lipid complexes to fungal cells or to the higher thermodynamic stability of lipid formulations. Association with lipids modulates AmB binding to lipoproteins in vivo, thus influencing tissue distribution and toxicity. For example, lipid complexes of AmB can be internalized by macrophages, and the macrophages then serve as a reservoir for the drug. Furthermore, stable AmB-lipid complexes are much less toxic to the host than Fungizone and can therefore be administered in higher doses. Experimentally, the efficacy of AmB-lipid formulations compared with Fungizone depends on the animal model used. Improved therapeutic indices for AmB-lipid formations have been demonstrated in clinical trials, but the definitive trials leading to the selection of an optimal formulation and therapeutic regimen have not been done.

scholarly journals Antileishmanial Activity of Dimeric Flavonoids Isolated from Arrabidaea brachypoda

Molecules ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 1 ◽  
Author(s):  
Vinícius Rocha ◽  
Cláudia Quintino da Rocha ◽  
Emerson Ferreira Queiroz ◽  
Laurence Marcourt ◽  
Wagner Vilegas ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Therapeutic Index ◽  
New Drugs ◽  
In Vitro Activity ◽  
Cell Toxicity ◽  
Narrow Therapeutic Index ◽  
High Accumulation ◽  
Cytoplasmic Vesicles ◽  
Secondary Line

Leishmaniasis are diseases caused by parasites belonging to Leishmania genus. The treatment with pentavalent antimonials present high toxicity. Secondary line drugs, such as amphotericin B and miltefosine also have a narrow therapeutic index. Therefore, there is an urgent need to develop new drugs to treat leishmaniasis. Here, we present the in vitro anti-leishmanial activity of unusual dimeric flavonoids purified from Arrabidaea brachypoda. Three compounds were tested against Leishmana sp. Compound 2 was the most active against promastigotes. Quantifying the in vitro infected macrophages revealed that compound 2 was also the most active against intracellular amastigotes of L. amazonensis, without displaying host cell toxicity. Drug combinations presented an additive effect, suggesting the absence of interaction between amphotericin B and compound 2. Amastigotes treated with compound 2 demonstrated alterations in the Golgi and accumulation of vesicles inside the flagellar pocket. Compound 2-treated amastigotes presented a high accumulation of cytoplasmic vesicles and a myelin-like structure. When administered in L. amazonensis-infected mice, neither the oral nor the topical treatments were effective against the parasite. Based on the high in vitro activity, dimeric flavonoids can be used as a lead structure for the development of new molecules that could be useful for structure-active studies against Leishmania.

scholarly journals Behavior of amphotericin B lipid complex in plasma in vitro and in the circulation of rats.

1997 ◽  
Vol 41 (5) ◽  
pp. 886-892 ◽  
Author(s):  
R Bhamra ◽  
A Sa'ad ◽  
L E Bolcsak ◽  
A S Janoff ◽  
C E Swenson
Keyword(s):  
Amphotericin B ◽  
Therapeutic Index ◽  
Parent Material ◽  
Protein Distribution ◽  
Time Curve ◽  
Lipid Complex ◽  
Amphotericin B Lipid Complex ◽  
Reduced Toxicity

Amphotericin B lipid complex (ABLC) shows reduced toxicity relative to that of amphotericin B deoxycholate (AmB-d) while maintaining antifungal activity. Rat blood or plasma was spiked with ABLC in vitro. Released amphotericin B was separated from the parent material by centrifugation. At early times (0 to 15 min) most (approximately 90%) of the amphotericin B was complexed. The amount of released amphotericin B increased gradually in a time- and temperature-dependent fashion. The released amphotericin B was associated with plasma lipoprotein and nonlipoprotein proteins. The area under the concentration-time curve from 0 to 24 h for total amphotericin B in whole blood of rats given a single intravenous bolus dose of 1 mg of ABLC per kg of body weight was fourfold lower than that in rats given 1 mg of AmB-d per kg. The complexed amphotericin B was rapidly removed from the circulation and was distributed to the tissues in these rats. Other rats were treated intravenously with ABLC (10 mg/kg/day) or AmB-d (0.5 mg/kg/day) daily for 15 days. Blood was collected at 15 and 180 min after administration of the last dose. The total levels of amphotericin B in the blood of the group given ABLC were about three to five times those in the group given AmB-d, and the concentration of released, protein-bound amphotericin B in the plasma of the group given ABLC was about one to two times that observed for the group given AmB-d, despite the 20-fold difference in dose. The relative protein distribution of amphotericin B in plasma was similar after ABLC or AmB-d administration under these steady-state conditions in vivo. The rapid uptake of complexed amphotericin B by tissues and the very low levels of circulating protein-bound amphotericin B in plasma after the administration of ABLC may explain, in part, the reduced toxicity and enhanced therapeutic index of this preparation.

scholarly journals Heat-induced superaggregation of amphotericin B reduces its in vitro toxicity: a new way to improve its therapeutic index.

1997 ◽  
Vol 41 (11) ◽  
pp. 2345-2351 ◽  
Author(s):  
F Gaboriau ◽  
M Chéron ◽  
C Petit ◽  
J Bolard
Keyword(s):  
Heat Treatment ◽  
Amphotericin B ◽  
Mammalian Cells ◽  
Therapeutic Index ◽  
In Vitro Toxicity ◽  
Thermal Pretreatment ◽  
Colloidal Solutions ◽  
Lactate Dehydrogenase Release ◽  
Diphenyltetrazolium Bromide

Superaggregation of amphotericin B (AmB) was previously shown to occur upon heating of solutions at 70 degrees C. In the present study, we demonstrate that heat pretreatment of Fungizone (deoxycholate salt of AmB [AmB-DOC]) solutions induces a drastic decrease in the in vitro toxicity of this antibiotic. Heated AmB-DOC colloidal solutions, which mainly contained superaggregated and monomeric forms of the antibiotic, were strongly less hemolytic than unheated solutions (aggregates and monomers). Thermal pretreatment of AmB-DOC solutions also reduced the toxicity to the cell line HT29, as deduced from two simultaneous cell viability assays (3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase release). These heated colloidal solutions were only slightly less efficient than the unheated ones at inhibiting the growth of Candida albicans cells in vitro. Such results suggest that mild heat treatment of AmB-DOC solutions could provide a new and simple solution for improving the therapeutic index of this antifungal agent by reducing its toxicity to mammalian cells.

scholarly journals Invasive infections with Purpureocillium lilacinum: clinical characteristics and outcome of 101 cases from FungiScope® and the literature

2021 ◽  
Author(s):  
Rosanne Sprute ◽  
Jon Salmanton-García ◽  
Ertan Sal ◽  
Xhorxha Malaj ◽  
Zdeněk Ráčil ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Organ Transplant ◽  
Solid Organ ◽  
Intrinsic Resistance ◽  
Breakthrough Infection ◽  
Purpureocillium Lilacinum ◽  
Invasive Infections ◽  
Oncological Diseases ◽  
Overall Mortality

Abstract Objectives To provide a basis for clinical management decisions in Purpureocillium lilacinum infection. Methods Unpublished cases of invasive P. lilacinum infection from the FungiScope® registry and all cases reported in the literature were analysed. Results We identified 101 cases with invasive P. lilacinum infection. Main predisposing factors were haematological and oncological diseases in 31 cases (30.7%), steroid treatment in 27 cases (26.7%), solid organ transplant in 26 cases (25.7%), and diabetes mellitus in 19 cases (18.8%). The most prevalent infection sites were skin (n = 37/101, 36.6%) and lungs (n = 26/101, 25.7%). Dissemination occurred in 22 cases (21.8%). Pain and fever were the most frequent symptoms (n = 40/101, 39.6% and n = 34/101, 33.7%, respectively). Diagnosis was established by culture in 98 cases (97.0%). P. lilacinum caused breakthrough infection in 10 patients (9.9%). Clinical isolates were frequently resistant to amphotericin B, whereas posaconazole and voriconazole showed good in vitro activity. Susceptibility to echinocandins varied considerably. Systemic antifungal treatment was administered in 90 patients (89.1%). Frequently employed antifungals were voriconazole in 51 (56.7%) and itraconazole in 26 patients (28.9%). Amphotericin B treatment was significantly associated with high mortality rates (n = 13/33, 39.4%, P = <0.001). Overall mortality was 21.8% (n = 22/101) and death was attributed to P. lilacinum infection in 45.5% (n = 10/22). Conclusions P. lilacinum mainly presents as soft-tissue, pulmonary or disseminated infection in immunocompromised patients. Owing to intrinsic resistance, accurate species identification and susceptibility testing are vital. Outcome is better in patients treated with triazoles compared with amphotericin B formulations.

scholarly journals Polishing the Therapy of Onychomycosis Induced by Candida spp.: Amphotericin B–Loaded Nail Lacquer

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 784
Author(s):  
Aleph M. S. Souza ◽  
Renato C. A. Ribeiro ◽  
Gleyse K. L. O. Pinheiro ◽  
Francisco I. Pinheiro ◽  
Wógenes N. Oliveira ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Ex Vivo ◽  
Drug Loading ◽  
Drug Bioavailability ◽  
Candida Spp ◽  
Drying Time ◽  
Analytical Method Validation ◽  
Nail Lacquer ◽  
In Vitro Adhesion

Onychomycosis induced by Candida spp. has several limitations regarding its treatment. Nail lacquers display the potential to overcome these drawbacks by providing therapeutic compliance and increasing local drug bioavailability. Thus, this work aimed to produce a nail lacquer loaded with Amphotericin B (AmB) and evaluate its performance. The AmB-loaded nail lacquer was produced and preliminarily characterized. An AmB quantification method was developed. Stability, drug release, permeability and anti-Candida activity assays were conducted. The analytical method validation met the acceptance criteria. The drug loading efficiency was 100% (0.02 mg/g of total product), whereas the AmB stability was limited to ≅ 7 days (≅ 90% remaining). The nail lacquer displayed a drying time of 187 s, non-volatile content of around 20%w/w, water-resistance of approximately 2%w/w of weight loss and satisfactory in vitro adhesion. Moreover, the in vitro antifungal activity against different Candida spp. strains was confirmed. The AmB release and the ex vivo permeability studies revealed that AmB leaves the lacquer and permeates the nail matrix in 47.76 ± 0.07% over 24 h. In conclusion, AmB-loaded nail lacquer shows itself as a promising extemporaneous dosage form with remarkable anti-Candida activity related to onychomycosis.

scholarly journals Synthesis and Activity of New Schiff Bases of Furocoumarin

2020 ◽  
Vol 26 (1) ◽  
pp. 176-184
Author(s):  
Huijun Xie ◽  
Chao Niu ◽  
Zeyang Chao ◽  
Nuramina Mamat ◽  
Haji Akber Aisa
Keyword(s):  
Animal Models ◽  
Amphotericin B ◽  
Molecular Mechanism ◽  
Schiff Bases ◽  
Positive Control ◽  
Excellent Performance ◽  
Activation Rate ◽  
Antibacterial Spectrum ◽  
Better Than

AbstractFurocoumarins, such as 8-MOP, are the most common medications used to relieve the symptoms of vitiligo clinically. Some furocoumarins also showed excellent performance in an anti-bacterial assay. This paper describes the synthesis of a series of novel Schiff bases (6a-6k), and their promotion in melanogenesis and anti-bacterial properties were studied in vitro.The pigment production of B16 cells and bacterial inhibition ring assay were applied for the bioactivity of 6a-6k. According to the results, a stronger promotion on pigment content was observed, when six compounds co-cultured with cells, compared with positive control (8-MOP). Significantly, compound 6k (237%) as the most active was found to increase the amount of melanin more than 1.7 times compared with 8-MOP activation rate (136%). All the compounds could moderately retard C. albicans growth. Interestingly, aldehyde 5, which possessed a broader antibacterial spectrum, showed the highest inhibition against C. albicans as well and much better than the positive control (Amphotericin B).Studies of 6k in animal models of vitiligo and related molecular mechanism are presently under way, with the aim of discovering an anti-vitiligo leading compound.

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