1
|
Takei-Masuda N, Nagira Y, Kubota-Ishida N, Chikada T, Tabata Y, Maebashi K. Antidermatophyte activity and PK/PD of ME1111 in a guinea pig model of tinea corporis. J Antibiot (Tokyo) 2024:10.1038/s41429-024-00738-y. [PMID: 38769156 DOI: 10.1038/s41429-024-00738-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 04/17/2024] [Accepted: 04/19/2024] [Indexed: 05/22/2024]
Abstract
Onychomycosis, a superficial fungal infection of the nails, is prevalent in many areas of the world. Topical agents for onychomycosis need to reach the subungual layer and nail bed to exert antifungal activity in the presence of keratin, the major component of the nail. It is difficult to evaluate the efficacy and pharmacodynamics of topical agents for onychomycosis in a non-clinical evaluation system. No consistent animal model has yet been established to predict the efficacy of topical agents for onychomycosis. In this study, we evaluated the pharmacokinetics and pharmacodynamics of ME1111 in a guinea pig model of tinea corporis designed to predict the efficacy of topical medication for onychomycosis in the vicinity of the nail bed. Trichophyton mentagrophytes TIMM1189 was infected on the back skin of guinea pigs, and ME1111 solution (5%, 10%, or 15%) was administered topically, once daily for 14 consecutive days. Following the completion of dosing, segments of skin from the site of infection were excised and cultured. The concentration of ME1111 in the back skin of guinea pigs increased with formulation concentration and correlated with mycological efficacy. We revealed the concentration required for ME1111 to be effective at the site of infection. Further analysis is needed to predict the efficacy of topical agents for onychomycosis by analyzing the relationship between PK/PD around the nail bed and factors such as subungual penetration and permeability.
Collapse
Affiliation(s)
| | - Yu Nagira
- Meiji Seika Pharma Co., Ltd., Tokyo, Japan
| | | | | | | | | |
Collapse
|
2
|
Facchini N, Wernli L, Rieken M, Bonkat G, Wirz D, Braissant O. Again and Again-Survival of Candida albicans in Urine Containing Antifungals. Pharmaceutics 2024; 16:605. [PMID: 38794267 PMCID: PMC11124869 DOI: 10.3390/pharmaceutics16050605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 05/26/2024] Open
Abstract
BACKGROUND Relapse of Candida albicans urinary tract infection (UTI) is frequent despite appropriate treatment, as commonly used antifungals such fluconazole and flucytosine are only fungistatics. To improve treatment of Candida UTI and decrease relapses, understanding the long-term metabolic activity and survival of C. albicans in urine containing antifungals at minimal inhibitory concentration (MIC) is needed. METHODS we monitored the survival, metabolic activity and consumption of glucose and proteins by C. albicans using conventional methods and isothermal microcalorimetry (IMC). We also investigated the influence of dead Candida cells on the growth of their living counterparts. RESULTS For 33 days, weak activity was observed in samples containing antifungals in which C. albicans growth rate was reduced by 48%, 60% and 88%, and the lag increased to 172 h, 168 h and 6 h for amphotericin, flucytosine and fluconazole, respectively. The metabolic activity peaks corresponded to the plate counts but were delayed compared to the exhaustion of resources. The presence of dead cells promoted growth in artificial urine, increasing growth rate and reducing lag in similar proportions. CONCLUSIONS Even with antifungal treatment, C. albicans relapses are possible. The low metabolic activity of surviving cells leading to regrowth and chlamydospore formation possibly supported by autophagy are likely important factors in relapses.
Collapse
Affiliation(s)
- Nevio Facchini
- Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167B/C, 4123 Allschwil, Switzerland; (N.F.)
- Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland
| | - Lukas Wernli
- Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167B/C, 4123 Allschwil, Switzerland; (N.F.)
- Department of Urology, Kantonsspital Baselland, Rheinstrasse 26, 4410 Liestal, Switzerland
| | - Malte Rieken
- Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland
- alta uro AG, Centralbahnplatz 6, 4051 Basel, Switzerland
| | - Gernot Bonkat
- Faculty of Medicine, University of Basel, Klingelbergstrasse 61, 4056 Basel, Switzerland
- alta uro AG, Centralbahnplatz 6, 4051 Basel, Switzerland
| | - Dieter Wirz
- Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167B/C, 4123 Allschwil, Switzerland; (N.F.)
| | - Olivier Braissant
- Department of Biomedical Engineering, University of Basel, Hegenheimermattweg 167B/C, 4123 Allschwil, Switzerland; (N.F.)
| |
Collapse
|
3
|
Das BC, Adil Shareef M, Das S, Nandwana NK, Das Y, Saito M, Weiss LM. Boron-Containing heterocycles as promising pharmacological agents. Bioorg Med Chem 2022; 63:116748. [PMID: 35453036 DOI: 10.1016/j.bmc.2022.116748] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 03/16/2022] [Accepted: 04/08/2022] [Indexed: 11/28/2022]
Abstract
The incorporation of the "magic" boron atom has been established as an important new strategy in the field of medicinal chemistry as boron compounds have been shown to form various bonds with their biological targets. Currently, a number of boron-based drugs (e.g. bortezomib, crisaborole, and tavaborole) have been FDA approved and are in the clinic, and several other boron-containing compounds are in clinical trials. Boron-based heterocycles have an incredible potential in the ongoing quest for new therapeutic agents owing to their plethora of biological activities and useful pharmacokinetic profiles. The present perspective is intended to review the pharmacological applications of boron-based heterocycles that have been published. We have classified these compounds into groups exhibiting shared pharmacological activities and discussed their corresponding biological targets focusing mainly on the most potent therapeutic compounds.
Collapse
Affiliation(s)
- Bhaskar C Das
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY, USA; Department of Medicine and Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Mohammed Adil Shareef
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY, USA
| | - Sasmita Das
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY, USA
| | - Nitesh K Nandwana
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY, USA
| | - Yogarupa Das
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Mariko Saito
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA
| | - Louis M Weiss
- Department of Medicine, Division of Infectious Diseases and Department of Pathology Division of Parasitology and Tropical Medicine, Albert Einstein College of Medicine, Bronx NY-10461, USA
| |
Collapse
|
4
|
Das BC, Nandwana NK, Das S, Nandwana V, Shareef MA, Das Y, Saito M, Weiss LM, Almaguel F, Hosmane NS, Evans T. Boron Chemicals in Drug Discovery and Development: Synthesis and Medicinal Perspective. Molecules 2022; 27:2615. [PMID: 35565972 PMCID: PMC9104566 DOI: 10.3390/molecules27092615] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 02/06/2023] Open
Abstract
A standard goal of medicinal chemists has been to discover efficient and potent drug candidates with specific enzyme-inhibitor abilities. In this regard, boron-based bioactive compounds have provided amphiphilic properties to facilitate interaction with protein targets. Indeed, the spectrum of boron-based entities as drug candidates against many diseases has grown tremendously since the first clinically tested boron-based drug, Velcade. In this review, we collectively represent the current boron-containing drug candidates, boron-containing retinoids, benzoxaboroles, aminoboronic acid, carboranes, and BODIPY, for the treatment of different human diseases.In addition, we also describe the synthesis, key structure-activity relationship, and associated biological activities, such as antimicrobial, antituberculosis, antitumor, antiparasitic, antiprotozoal, anti-inflammatory, antifolate, antidepressant, antiallergic, anesthetic, and anti-Alzheimer's agents, as well as proteasome and lipogenic inhibitors. This compilation could be very useful in the exploration of novel boron-derived compounds against different diseases, with promising efficacy and lesser side effects.
Collapse
Affiliation(s)
- Bhaskar C. Das
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA; (N.K.N.); (S.D.); (V.N.); (M.A.S.)
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Surgery, Weill Cornell Medical College, Cornell University, New York, NY 10065, USA;
| | - Nitesh K. Nandwana
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA; (N.K.N.); (S.D.); (V.N.); (M.A.S.)
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Sasmita Das
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA; (N.K.N.); (S.D.); (V.N.); (M.A.S.)
| | - Varsha Nandwana
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA; (N.K.N.); (S.D.); (V.N.); (M.A.S.)
| | - Mohammed Adil Shareef
- Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY 11201, USA; (N.K.N.); (S.D.); (V.N.); (M.A.S.)
| | - Yogarupa Das
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; (Y.D.); (M.S.)
| | - Mariko Saito
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA; (Y.D.); (M.S.)
| | - Louis M. Weiss
- Department of Pathology, Division of Parasitology and Tropical Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Frankis Almaguel
- School of Medicine, Loma Linda University Health, Loma Linda, CA 92350, USA;
| | - Narayan S. Hosmane
- Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL 60115, USA;
| | - Todd Evans
- Department of Surgery, Weill Cornell Medical College, Cornell University, New York, NY 10065, USA;
| |
Collapse
|
5
|
Vlahovic TC, Gupta AK. Efinaconazole topical solution (10%) for the treatment of onychomycosis in adult and pediatric patients. Expert Rev Anti Infect Ther 2021; 20:3-15. [PMID: 34106031 DOI: 10.1080/14787210.2021.1939011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Introduction: Onychomycosis, a common nail disorder caused by fungal infection, can be managed pharmaceutically with oral or topical treatments. While oral treatments are often used first-line to treat nail infections, these systemic antifungals are not appropriate for all patients, and no oral treatments are approved for use in children in the USA. Given this need, topical antifungals were developed, which can be used as monotherapy or in combination with oral drugs.Areas Covered: Efinaconazole 10% solution is an azole antifungal indicated for topical treatment of toenail onychomycosis in pediatric and adult patients. This qualitative literature review summarizes available chemical, pharmacological, efficacy, safety, and post-marketing surveillance data of efinaconazole 10% topical solution. Efinaconazole 10% has been shown to be safe and efficacious regardless of disease severity/duration at baseline; patient gender, ethnicity, or age (including pediatrics); or comorbidities such as diabetes or tinea pedis. Overall, efinaconazole is a safe and effective clinical option for the treatment and management of onychomycosis.Expert Opinion: Efinaconazole is the first new antifungal approved for onychomycosis in 10 years in the USA. It has comparable efficacy to systemic antifungal agents such as itraconazole, and a favorable adverse events profile with minimal systemic exposure and no drug-drug interactions.
Collapse
Affiliation(s)
- Tracey C Vlahovic
- Temple University School of Podiatric Medicine, Philadelphia, PA, US
| | - Aditya K Gupta
- Mediprobe Research Inc., London, ON, CAN.,Department of Medicine, University of Toronto, Toronto, ON, CAN
| |
Collapse
|
6
|
Estevez-Fregoso E, Farfán-García ED, García-Coronel IH, Martínez-Herrera E, Alatorre A, Scorei RI, Soriano-Ursúa MA. Effects of boron-containing compounds in the fungal kingdom. J Trace Elem Med Biol 2021; 65:126714. [PMID: 33453473 DOI: 10.1016/j.jtemb.2021.126714] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/10/2020] [Accepted: 01/04/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND The number of known boron-containing compounds (BCCs) is increasing due to their identification in nature and innovative synthesis procedures. Their effects on the fungal kingdom are interesting, and some of their mechanisms of action have recently been elucidated. METHODS In this review, scientific reports from relevant chemistry and biomedical databases were collected and analyzed. RESULTS It is notable that several BCC actions in fungi induce social and economic benefits for humans. In fact, boric acid was traditionally used for multiple purposes, but some novel synthetic BCCs are effective antifungal agents, particularly in their action against pathogen species, and some were recently approved for use in humans. Moreover, most reports testing BCCs in fungal species suggest a limiting effect of these compounds on some vital reactions. CONCLUSIONS New BCCs have been synthesized and tested for innovative technological and biomedical emerging applications, and new interest is developing for discovering new strategic compounds that can act as environmental or wood protectors, as well as antimycotic agents that let us improve food acquisition and control some human infections.
Collapse
Affiliation(s)
- Elizabeth Estevez-Fregoso
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340, Mexico
| | - Eunice D Farfán-García
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340, Mexico.
| | - Itzel H García-Coronel
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340, Mexico; Unidad de Investigación, Hospital Regional de Alta Especialidad Ixtapaluca, Carretera Federal México-Puebla km 34.5, C.P. 56530, Ixtapaluca, State of Mexico, Mexico
| | - Erick Martínez-Herrera
- Unidad de Investigación, Hospital Regional de Alta Especialidad Ixtapaluca, Carretera Federal México-Puebla km 34.5, C.P. 56530, Ixtapaluca, State of Mexico, Mexico
| | - Alberto Alatorre
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340, Mexico
| | - Romulus I Scorei
- BioBoron Research Institute, Dunarii 31B Street, 207465, Podari, Romania
| | - Marvin A Soriano-Ursúa
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340, Mexico.
| |
Collapse
|
7
|
In Vitro Resistance and Evolution of Resistance to Tavaborole in Trichophyton rubrum. Antimicrob Agents Chemother 2021; 65:AAC.02324-20. [PMID: 33468466 DOI: 10.1128/aac.02324-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 01/04/2021] [Indexed: 11/20/2022] Open
Abstract
Tavaborole is currently used in the topical treatment of onychomycosis. In this study, we analyzed the in vitro emergence/evolution of resistance against tavaborole in Trichophyton rubrum When T. rubrum strains were propagated on media containing the MIC of tavaborole, spontaneous resistant mutants were isolated at a frequency of 10-8 The frequency was almost 100-fold higher following fungal growth in the presence of a subinhibitory tavaborole concentration (0.5-fold the MIC) for 10 transfers. All collected mutants showed similar 4- to 8-fold increases in the drug MIC. No cross-resistance to other antifungals was evident.
Collapse
|
8
|
Vikas A, Rashmin P, Mrunali P, Chavan RB, Kaushik T. Mechanistic Insights of Formulation Approaches for the Treatment of Nail Infection: Conventional and Novel Drug Delivery Approaches. AAPS PharmSciTech 2020; 21:67. [PMID: 31938980 DOI: 10.1208/s12249-019-1591-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 11/25/2019] [Indexed: 02/07/2023] Open
Abstract
Onychomycosis is a chronic disorder that is difficult to manage and hard to eradicate with perilous trends to relapse. Due to increased prevalence of HIV, use of immunosuppressant drugs and lifestyle-related factors, population affected with fungal infection of nail (Onychomycosis) happens to increase extensively in last two decades. Modalities available for the treatment of onychomycosis include systemically administered antifungals, mechanical procedures, and topical drug therapy. But the efficacy of the most of approaches to deliver drug at targeted site, i.e., deep-seated infected nail bed is limited due to compact and highly keratinized nail structure. A series of advanced formulation approaches, such as transfersomes, liposomes, nano/micro emulsion, nail lacquers etc., have been attempted to improve the drug penetration into nail plate more efficiently. The manuscript reviews these formulation approaches with their possible mechanisms by which they improve the drug penetration.Comparative analysis of available treatment modalities for onychomycosis has been provided with pros and cons of each alternatives. Additionally, ongoing research about the application of biological materials such as modified cationic antimicrobial peptides (AMPs), plant-derived proteins, and synthetic antimicrobial peptidomimetics have also been explored.
Collapse
|
9
|
Ahmad S, Usman Minhas M, Ahmad M, Sohail M, Abdullah O, Khan KU. Topical hydrogel patches of vinyl monomers containing mupirocin for skin injuries: Synthesis and evaluation. ADVANCES IN POLYMER TECHNOLOGY 2018. [DOI: 10.1002/adv.22124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Sarfaraz Ahmad
- Faculty of Pharmacy and Alternative Medicine; The Islamia University of Bahawalpur; Bahawalpur Pakistan
| | - Muhammad Usman Minhas
- Faculty of Pharmacy and Alternative Medicine; The Islamia University of Bahawalpur; Bahawalpur Pakistan
| | - Mahmood Ahmad
- Faculty of Pharmacy and Alternative Medicine; The Islamia University of Bahawalpur; Bahawalpur Pakistan
| | - Muhammad Sohail
- Department of Pharmacy; COMSATS Institute of Information Technology; Abbottabad Pakistan
| | - Orva Abdullah
- Faculty of Pharmacy and Alternative Medicine; The Islamia University of Bahawalpur; Bahawalpur Pakistan
| | - Kifayat Ullah Khan
- Faculty of Pharmacy and Alternative Medicine; The Islamia University of Bahawalpur; Bahawalpur Pakistan
| |
Collapse
|
10
|
|
11
|
Lubis NZ, Muis K, Nasution LH. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism as a Confirmatory Test for Onychomycosis. Open Access Maced J Med Sci 2018; 6:280-283. [PMID: 29531588 PMCID: PMC5839432 DOI: 10.3889/oamjms.2018.098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 01/16/2018] [Accepted: 01/20/2018] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Onychomycosis is a fungal infection of one or more units of the nail caused by dermatophytes, or mould and nondermatophytes yeast. Investigations are needed to establish the diagnosis of onychomycosis before starting treatment. Several investigations methods for diagnosing onychomycosis are microscopic examination with 20% KOH, fungal culture, histopathology examination with PAS staining (Periodic acid Schiff) and PCR (Polymerase Chain Reaction). Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) is a method after PCR amplification allowing more specific results. AIM To determine the diagnostic value of PCR - RFLP in the diagnosis of onychomycosis using fungal culture as the gold standard and to find out the majority fungal species that cause onychomycosis. METHODS This study is a diagnostic test for the diagnosis of onychomycosis by using culture as the gold standard. SUBJECTS Thirty - five patients suspected of having onychomycosis from history and dermatological examination. RESULTS PCR - RFLP in the diagnosis of onychomycosis has a sensitivity of 85.71%, specificity of 28.57%, positive predictive value (PPV) of 82.76% and negative predictive value (NPV) of 33.33%. The positive and negative likelihood ratios are 1.20 and 0.5 with an accuracy of 74.29%. CONCLUSIONS PCR - RFLP may be considered for a faster and more accurate alternative examination in the diagnosis of onychomycosis.
Collapse
Affiliation(s)
- Nova Zairina Lubis
- Universitas Sumatera Utara, Dermatology and Venereology, Medan, North Sumatera, Indonesia
| | - Kamaliah Muis
- Universitas Sumatera Utara, Dermatology and Venereology, Medan, North Sumatera, Indonesia
| | | |
Collapse
|
12
|
Chanana M, Kumar A, Tyagi SP, Singla AK, Sharma A, Farooq UB. End-threaded intramedullary positive profile screw ended self-tapping pin (Admit pin) - A cost-effective novel implant for fixing canine long bone fractures. Vet World 2018; 11:181-185. [PMID: 29657401 PMCID: PMC5891872 DOI: 10.14202/vetworld.2018.181-185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 01/05/2018] [Indexed: 11/16/2022] Open
Abstract
Aim The current study was undertaken to evaluate the clinical efficacy of end-threaded intramedullary pinning for management of various long bone fractures in canines. Materials and Methods This study was conducted in two phases, managing 25 client-owned dogs presented with different fractures. The technique of application of end-threaded intramedullary pinning in long bone fractures was initially standardized in 6 clinical patients presented with long bone fractures. In this phase, end-threaded pins of different profiles, i.e., positive and negative, were used as the internal fixation technique. On the basis of results obtained from standardization phase, 19 client-owned dogs clinically presented with different fractures were implanted with end-threaded intramedullary positive profile screw ended self-tapping pin in the clinical application phase. Results The patients, allocated randomly in two groups, when evaluated postoperatively revealed slight pin migration in Group-I (negative profile), which resulted in disruption of callus site causing delayed union in one case and large callus formation in other two cases whereas no pin migration was observed in Group-II (positive profile). Other observations in Group-I was reduced muscle girth and delayed healing time as compared to Group-II. In clinical application, phase 21st and 42nd day post-operative radiographic follow-up revealed no pin migration in any of the cases, and there was no bone shortening or fragment collapse in end-threaded intramedullary positive profile screw ended self-tapping pin. Conclusion The end-threaded intramedullary positive profile screw ended self-tapping pin used for fixation of long bone fractures in canines can resist pin migration, pin breakage, and all loads acting on the bone, i.e., compression, tension, bending, rotation, and shearing to an extent with no post-operative complications.
Collapse
Affiliation(s)
- Mitin Chanana
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| | - Adarsh Kumar
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| | - Som Prakash Tyagi
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| | - Amit Kumar Singla
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| | - Arvind Sharma
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| | - Uiase Bin Farooq
- Department of Veterinary Surgery and Radiology, College of Veterinary and Animal Sciences, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 061, Himachal Pradesh, India
| |
Collapse
|
13
|
Markinson B, Ghannoum M, Winter T, Rycerz A, Rock F, Gupta AK. Examining the Benefits of the Boron-Based Mechanism of Action and Physicochemical Properties of Tavaborole in the Treatment of Onychomycosis. J Am Podiatr Med Assoc 2018; 108:12-19. [PMID: 29547036 DOI: 10.7547/16-154] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Onychomycosis is a fungal infection of the nail primarily caused by the dermatophytes Trichophyton rubrum and Trichophyton mentagrophytes. The topical-based treatment of onychomycosis remains a challenge because of the difficulty associated with penetrating the dense, protective structure of the keratinized nail plate. Tavaborole is a novel small-molecule antifungal agent recently approved in the United States for the topical treatment of toenail onychomycosis. The low molecular weight, slight water solubility, and boron chemistry of tavaborole maximize nail penetration after topical application, allowing for effective targeting of the infection in the nail bed. The efficacy of tavaborole is associated with its novel mechanism of action, whereby it inhibits the fungal leucyl-tRNA synthetase (LeuRS) enzyme. Because LeuRS is an essential component in fungal protein synthesis, inhibition of LeuRS ultimately leads to fungal cell death. Tavaborole is the first boron-based antifungal medication approved for the treatment of mild-to-moderate onychomycosis and presents patients with a new topical option. Previously, ciclopirox and efinaconazole were the only approved topical treatments for onychomycosis. This article details the properties that are at the core of the clinical benefits associated with tavaborole.
Collapse
Affiliation(s)
| | - Mahmoud Ghannoum
- Department of Dermatology, Case Western Reserve University, Cleveland, OH
| | | | | | - Fernando Rock
- Anacor Pharmaceuticals Inc, a wholly owned subsidiary of Pfizer, Inc, New York, NY
| | | |
Collapse
|
14
|
In Vitro Human Onychopharmacokinetic and Pharmacodynamic Analyses of ME1111, a New Topical Agent for Onychomycosis. Antimicrob Agents Chemother 2017; 62:AAC.00779-17. [PMID: 29084749 DOI: 10.1128/aac.00779-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 10/22/2017] [Indexed: 11/20/2022] Open
Abstract
ME1111 is a novel antifungal agent currently under clinical development as a topical onychomycosis treatment. A major challenge in the application of topical onychomycotics is penetration and dissemination of antifungal agent into the infected nail plate and bed. In this study, pharmacokinetic/pharmacodynamic parameters of ME1111 that potentially correlate with clinical efficacy were compared with those of marketed topical onychomycosis antifungal agents: efinaconazole, tavaborole, ciclopirox, and amorolfine. An ME1111 solution and other launched topical formulations were applied to an in vitro dose model for 14 days based on their clinical dose and administration. Drug concentrations in the deep layer of the nail and within the cotton pads beneath the nails were measured using liquid chromatography-tandem mass spectrometry. Concentrations of ME1111 in the nail and cotton pads were much higher than those of efinaconazole, ciclopirox, and amorolfine. Free drug concentrations of ME1111 in deep nail layers and cotton pads were orders of magnitude higher than the MIC90 value against Trichophyton rubrum (n = 30). Unlike other drugs, the in vitro antifungal activity of ME1111 was not affected by 5% human keratin and under a mild acidic condition (pH 5.0). The in vitro antidermatophytic efficacy coefficients (ratio of free drug concentration to MIC90s against T. rubrum) of ME1111, as measured in deep nail layers, were significantly higher than those of efinaconazole, tavaborole, ciclopirox, and amorolfine (P < 0.05). This suggests that ME1111 has excellent permeation of human nails and, consequently, the potential to be an effective topical onychomycosis treatment.
Collapse
|
15
|
Design, Synthesis and X-ray Crystal Structure of Iodinated Benzoboroxole Derivatives by Consecutive Metal-Iodine Exchange of 3,4,5-Triiodoanisole. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700989] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
16
|
Toukabri N, Corpologno S, Bougnoux ME, El Euch D, Sadfi-Zouaoui N, Simonetti G. In vitro biofilms and antifungal susceptibility of dermatophyte and non-dermatophyte moulds involved in foot mycosis. Mycoses 2017; 61:79-87. [PMID: 28940733 DOI: 10.1111/myc.12706] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/11/2017] [Accepted: 09/18/2017] [Indexed: 11/29/2022]
Abstract
Tinea pedis and onychomycosis are among the commonest fungal diseases in the world. Dermatophytes and, less frequently, non-dermatophyte moulds are aetiological agents of foot mycosis and are capable of forming biofilms. Fungal biofilm has demonstrated increasing drug resistance. This work aims to evaluate, in vitro, the ability to form biofilm and the susceptibility to antifungal drugs of sessile dermatophytes and non-dermatophyte moulds involved in foot mycosis. Thirty-six dermatophytes and non-dermatophyte moulds isolated from Tunisian patients with foot mycoses, and identified with MALDI-TOF have been tested. MICs of fluconazole, econazole, itraconazole, terbinafine and griseofulvin were carried out using CLSI broth microdilution method. The ability to form biofilm and antifungal activities of drugs against fungal biofilm formation has been quantified by Crystal Violet and Safranin Red staining. Biomass quantification revealed that all species studied were able to form biofilms in vitro after 72 hours. Fluconazole, econazole, itraconazole and terbinafine inhibited fungal growth with MIC values ranging from 0.031 to >64 μg mL-1 . The best antifungal activity has been obtained with terbinafine against Fusarium solani. Econazole showed the highest activity against fungal biofilm formation. These findings can help clinicians to develop the appropriate therapy of foot mycosis.
Collapse
Affiliation(s)
- Nourchéne Toukabri
- Laboratory of Mycology, Pathologies and Biomarkers, Faculty of Sciences of Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Serena Corpologno
- Department of Public Health and Infectious Diseases, "Sapienza" University of Rome, Rome, Italy
| | - Marie-Elisabeth Bougnoux
- Department of Microbiology, Hôpital Necker-Enfants Malades AP-HP, University Paris-Descartes, Paris, France
| | - Dalenda El Euch
- Department of Dermatology and Venereology, Hôpital La Rabta, Tunis, Tunisia
| | - Najla Sadfi-Zouaoui
- Laboratory of Mycology, Pathologies and Biomarkers, Faculty of Sciences of Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Giovanna Simonetti
- Department of Public Health and Infectious Diseases, "Sapienza" University of Rome, Rome, Italy
| |
Collapse
|
17
|
Piraccini BM, Starace M, Toft A. Early Visible Improvements during K101-03 Treatment: An Open-Label Multicenter Clinical Investigation in Patients with Onychomycosis and/or Nail Psoriasis. Dermatology 2017; 233:178-183. [PMID: 28787710 DOI: 10.1159/000478257] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 06/02/2017] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Onychomycosis and nail psoriasis can be embarrassing to patients, so improving the appearance of affected nails should be one of the key short-term goals of treatment. METHODS An 8-week open-label multicenter study was conducted to assess whether K101-03, a marketed topical treatment containing propylene glycol, glycerol, urea, and lactic acid, could produce rapid cosmetic improvements in affected nails. Adult patients with a big toenail or thumbnail (the "target" nail) affected by onychomycosis (n = 72) or psoriasis (n = 34) or both (n = 1) applied K101-03 to their affected nails once a day for 8 weeks. During and after treatment, patients rated the overall appearance of their target nail on a 4-point scale. They also assessed whether thickening, discoloration, brittleness, and softness of the target nail had improved since baseline. Adverse events (AEs) that occurred between the first application of K101-03 and the end of treatment were recorded and categorized according to severity and relationship to K101-03. RESULTS After 8 weeks of K101-03 treatment, 92.2% of patients (95% confidence interval [CI] 87.06-97.40) reported at least some improvement in the target nail. After 1 week of treatment, 78.3% of patients with onychomycosis (95% CI 68.53-87.99) reported at least some improvement in the target nail, and 55.1% of them reported that discoloration of their target nail had improved. Three patients reported a total of 5 AEs, none of which were judged to be related to K101-03. CONCLUSIONS In summary, K101-03 was well tolerated in patients with onychomycosis or nail psoriasis and rapidly improved their nails.
Collapse
Affiliation(s)
- Bianca Maria Piraccini
- Department of Experimental, Diagnostic and Specialty Medicine, Università di Bologna, Bologna, Italy
| | | | | |
Collapse
|
18
|
Shimamura T, Hasegawa N, Kubota N. [Antifungal Activity of Luliconazole Nail Solution on in vitro and in vivo Onychomycosis Model]. Med Mycol J 2016; 57:J13-8. [PMID: 26936347 DOI: 10.3314/mmj.57.j13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We evaluated luliconazole nail solution, originally generated formulation, for the topical treatment of onychomycosis by two infection models. First, a suspension of Trichophyton mentagrophytes was dropped onto the ventral layer of human nail plate and these nails were set in Franz diffusion cells. After 9-day culture, luliconazole nail solutions (1, 3, and 5%) were applied to the dorsal surface of the nails once a day for 7 days. After application, fungal viability was assessed by measuring the ATP contents of the samples. The dose-dependent efficacy was confirmed, with 3% and 5% luliconazole nail solutions producing significantly lower ATP levels at 7-day treatment. When 3% and 5% luliconazole nail solutions were evaluated in a rabbit model of onychomycosis, both concentrations completely inhibited the recovery of fungi on culture after 4-week treatment. We therefore think these results indicate that 5% luliconazole nail solution is sufficiently potent for treatment of onychomycosis.
Collapse
|
19
|
Gupta AK, Foley KA, Versteeg SG. New Antifungal Agents and New Formulations Against Dermatophytes. Mycopathologia 2016; 182:127-141. [PMID: 27502503 DOI: 10.1007/s11046-016-0045-0] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 07/26/2016] [Indexed: 11/24/2022]
Abstract
A variety of oral and topical antifungal agents are available for the treatment of superficial fungal infections caused by dermatophytes. This review builds on the antifungal therapy update published in this journal for the first special issue on Dermatophytosis (Gupta and Cooper 2008;166:353-67). Since 2008, there have not been additions to the oral antifungal armamentarium, with terbinafine, itraconazole, and fluconazole still in widespread use, albeit for generally more severe or recalcitrant infections. Griseofulvin is used in the treatment of tinea capitis. Oral ketoconazole has fallen out of favor in many jurisdictions due to risks of hepatotoxicity. Topical antifungals, applied once or twice daily, are the primary treatment for tinea pedis, tinea corporis/tinea cruris, and mild cases of tinea unguium. Newer topical antifungal agents introduced include the azoles, efinaconazole, luliconazole, and sertaconazole, and the oxaborole, tavaborole. Research is focused on developing formulations of existing topical antifungals that utilize novel delivery systems in order to enhance treatment efficacy and compliance.
Collapse
Affiliation(s)
- Aditya K Gupta
- Department of Medicine, University of Toronto, Toronto, Canada. .,Mediprobe Research Inc., 645 Windermere Road, London, ON, Canada.
| | - Kelly A Foley
- Mediprobe Research Inc., 645 Windermere Road, London, ON, Canada
| | - Sarah G Versteeg
- Mediprobe Research Inc., 645 Windermere Road, London, ON, Canada
| |
Collapse
|
20
|
Antimalarial Benzoxaboroles Target Plasmodium falciparum Leucyl-tRNA Synthetase. Antimicrob Agents Chemother 2016; 60:4886-95. [PMID: 27270277 DOI: 10.1128/aac.00820-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 05/26/2016] [Indexed: 01/18/2023] Open
Abstract
There is a need for new antimalarials, ideally with novel mechanisms of action. Benzoxaboroles have been shown to be active against bacteria, fungi, and trypanosomes. Therefore, we investigated the antimalarial activity and mechanism of action of 3-aminomethyl benzoxaboroles against Plasmodium falciparum Two 3-aminomethyl compounds, AN6426 and AN8432, demonstrated good potency against cultured multidrug-resistant (W2 strain) P. falciparum (50% inhibitory concentration [IC50] of 310 nM and 490 nM, respectively) and efficacy against murine Plasmodium berghei infection when administered orally once daily for 4 days (90% effective dose [ED90], 7.4 and 16.2 mg/kg of body weight, respectively). To characterize mechanisms of action, we selected parasites with decreased drug sensitivity by culturing with stepwise increases in concentration of AN6426. Resistant clones were characterized by whole-genome sequencing. Three generations of resistant parasites had polymorphisms in the predicted editing domain of the gene encoding a P. falciparum leucyl-tRNA synthetase (LeuRS; PF3D7_0622800) and in another gene (PF3D7_1218100), which encodes a protein of unknown function. Solution of the structure of the P. falciparum LeuRS editing domain suggested key roles for mutated residues in LeuRS editing. Short incubations with AN6426 and AN8432, unlike artemisinin, caused dose-dependent inhibition of [(14)C]leucine incorporation by cultured wild-type, but not resistant, parasites. The growth of resistant, but not wild-type, parasites was impaired in the presence of the unnatural amino acid norvaline, consistent with a loss of LeuRS editing activity in resistant parasites. In summary, the benzoxaboroles AN6426 and AN8432 offer effective antimalarial activity and act, at least in part, against a novel target, the editing domain of P. falciparum LeuRS.
Collapse
|
21
|
Abstract
INTRODUCTION Onychomycosis is a fungal nail infection that accounts for half of all nail diseases. Oral drugs on the market have adverse effects, while it is difficult for traditional topical drugs to penetrate the nail plate to reach the diseased nail bed. Tavaborole is a new drug that addresses the unmet needs of currently available treatments. Tavaborole (5%) is FDA approved for treating toenail onychomycosis and has shown antifungal activities against yeast, moulds and dermatophytes. AREAS COVERED The objective of this article is to review the efficacy, pharmacokinetics, pharmacodynamics, and safety of tavaborole for treatment of toenail onychomycosis. Expert commentary: Tavaborole, with its unique mechanism, may be a good candidate for use in treating children with fungal infections, diabetic individuals, and treating mixed infections. Tavaborole may be paired with other therapies to potentially increase cure rates.
Collapse
Affiliation(s)
- Aditya K Gupta
- a Department of Medicine , University of Toronto School of Medicine , Toronto , ON , Canada.,b Mediprobe Research Inc ., London , ON , Canada
| | | |
Collapse
|
22
|
Ciaravino V, Coronado D, Lanphear C, Hoberman A, Chanda S. Tavaborole, a Novel Boron-Containing Small Molecule Pharmaceutical Agent for Topical Treatment of Onychomycosis: II. Prenatal and Postnatal Developmental Toxicity and Maternal Function Study. Int J Toxicol 2016; 35:543-57. [PMID: 27138050 DOI: 10.1177/1091581816641938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Tavaborole is a topical antifungal agent approved by the US Food and Drug Administration for the treatment of toenail onychomycosis. The effects of tavaborole on gestation, parturition (delivery, labor), offspring development, and survival during the perinatal and postnatal periods were assessed in mated female rats. Females (F0 generation) were administered single daily oral (gavage) doses of 15, 60, or 100 mg/kg/d from gestation day 6 through lactation day 20. The females were allowed to deliver naturally and rear their offspring until lactation day 21, at which time the F0 females were euthanized. One male and female from each litter were selected (F1 generation) and retained for assessments, including growth, neurobehavior, fertility, and their ability to produce an F2 generation. Reproductive and offspring parameters were determined for the F1 and F2 generations, as applicable. F1 females and F2 pups were euthanized on postnatal day 7. In the F0 females, decreased activity was observed in the 100 mg/kg/d dose group. Excess salivation was observed in the 60 and 100 mg/kg/d dose groups (slight to moderate), however, this finding was not considered adverse. There were no tavaborole-related effects on the growth, viability, development, neurobehavioral assessments, or reproductive performance of the F1 generation. Survivability and mean body weight of the F2 pups were unaffected. The no observed adverse effect level (NOAEL) for maternal toxicity (F0 generation) was 60 mg/kg/d, based on the decreased activity observed in the 100 mg/kg/d dose group. The NOAEL for the offspring effects was ≥100 mg/kg/d, based on the lack of test article-related changes.
Collapse
|
23
|
Kataria P, Sharma G, Thakur K, Bansal V, Dogra S, Katare OP. Emergence of nail lacquers as potential transungual delivery system in the management of onchomycosis. Expert Opin Drug Deliv 2016; 13:937-52. [DOI: 10.1080/17425247.2016.1174691] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
| | - Gajanand Sharma
- Division of Pharmaceutics, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Studies, Panjab University, Chandigarh, India
| | - Kanika Thakur
- Division of Pharmaceutics, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Studies, Panjab University, Chandigarh, India
| | - Vikas Bansal
- Chandigarh College of Pharmacy, Mohali, Punjab, India
| | - Sunil Dogra
- Department of Dermatology Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Om Prakash Katare
- Division of Pharmaceutics, University Institute of Pharmaceutical Sciences, UGC Centre of Advanced Studies, Panjab University, Chandigarh, India
| |
Collapse
|
24
|
Ciaravino V, Coronado D, Lanphear C, Hoberman A, Chanda S. Tavaborole, a Novel Boron-Containing Small Molecule Pharmaceutical Agent for Topical Treatment of Onychomycosis: I. Reproductive and Developmental Toxicity Studies. Int J Toxicol 2016; 35:530-42. [PMID: 27044640 DOI: 10.1177/1091581816639113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Tavaborole is a topical antifungal agent approved by the US Food and Drug Administration for the treatment of toenail onychomycosis. As part of the nonclinical development program, reproductive and developmental toxicity studies were conducted (rat oral fertility and early embryonic development, rat (oral) and rabbit (dermal) embryo-fetal development). There were no effects on fertility or reproductive performance at doses up to 300 mg/kg/d (107 times the maximum recommended human dose [MRHD] based on mean area under the plasma concentration-time curve comparisons). In the rat embryo-fetal development toxicity studies, teratogenicity was not observed at doses up to 100 mg/kg/d (29 times the MRHD). However, several treatment-related skeletal malformations and variations were observed at 300 mg/kg/d (570 times the MRHD). In rabbit embryo-fetal development toxicity studies dosed via oral or dermal administration, the no observable adverse effect level for maternal toxicity and embryo-fetal toxicity was 50 mg/kg/d (16 times the MRHD) and 5% (26 times the MRHD), respectively.
Collapse
|
25
|
Characterization of Antifungal Activity and Nail Penetration of ME1111, a New Antifungal Agent for Topical Treatment of Onychomycosis. Antimicrob Agents Chemother 2015; 60:1035-9. [PMID: 26643333 DOI: 10.1128/aac.01739-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 11/23/2015] [Indexed: 11/20/2022] Open
Abstract
Fungal nail infection (onychomycosis) is a prevalent disease in many areas of the world, with a high incidence approaching 23%. Available antifungals to treat the disease suffer from a number of disadvantages, necessitating the discovery of new efficacious and safe antifungals. Here, we evaluate the in vitro antifungal activity and nail penetration ability of ME1111, a novel antifungal agent, along with comparator drugs, including ciclopirox, amorolfine, terbinafine, and itraconazole. ME1111 showed potent antifungal activity against Trichophyton rubrum and Trichophyton mentagrophytes (the major etiologic agents of onychomycosis) strains isolated in Japan and reference fungal strains with an MIC range of 0.12 to 0.5 mg/liter and an MIC50 and MIC90 of 0.5 mg/liter for both. Importantly, none of the tested isolates showed an elevated ME1111 MIC. Moreover, the antifungal activity of ME1111 was minimally affected by 5% wool keratin powder in comparison to the other antifungals tested. The ME1111 solution was able to penetrate human nails and inhibit fungal growth in a dose-dependent manner according to the TurChub assay. In contrast, 8% ciclopirox and 5% amorolfine nail lacquers showed no activity under the same conditions. ME1111 demonstrated approximately 60-fold-greater selectivity in inhibition of Trichophyton spp. than of human cell lines. Our findings demonstrate that ME1111 possesses potent antidermatophyte activity, maintains this activity in the presence of keratin, and possesses excellent human nail permeability. These results suggest that ME1111 is a promising topical medication for the treatment of onychomycosis and therefore warrants further clinical evaluation.
Collapse
|
26
|
Abstract
Onychomycosis is a fungal nail plate infection that has been increasing in prevalence. A variety of oral and topical anti-fungal agents are currently available but their use is limited by their adverse effect profile, drug–drug interactions, and limited efficacy. Therefore, there is a great need for newer anti-fungal agents. Tavaborole is one of these newer agents and was approved by the US Food and Drug Administration in July 2014 for the topical treatment of mild to moderate toenail onychomycosis. Tavaborole is a novel, boron-based anti-fungal agent with greater nail plate penetration than its predecessors, due to its smaller molecular weight. It has proven through several Phase II and III trials that it can be a safe and effective topical agent for the treatment of mild to moderate toenail onychomycosis without the need for debridement. In this paper, we review the landscape of topical and systemic treatment of onychomycosis, with particular attention to the pharmacokinetics, safety, and efficacy of topical tavaborole.
Collapse
Affiliation(s)
- Sphoorthi Jinna
- Department of Dermatology, University of Connecticut School of Medicine, Farmington, CT, USA
| | - Justin Finch
- Department of Dermatology, University of Connecticut School of Medicine, Farmington, CT, USA
| |
Collapse
|
27
|
Queller JN, Bhatia N. The Dermatologist's Approach to Onychomycosis. J Fungi (Basel) 2015; 1:173-184. [PMID: 29376907 PMCID: PMC5753109 DOI: 10.3390/jof1020173] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 08/03/2015] [Accepted: 08/05/2015] [Indexed: 11/17/2022] Open
Abstract
Onychomycosis is a fungal infection of the toenails or fingernails that can involve any component of the nail unit, including the matrix, bed, and plate. It is a common disorder that may be a reservoir for infection resulting in significant medical problems. Moreover, onychomycosis can have a substantial influence on one's quality of life. An understanding of the disorder and updated management is important for all health care professionals. Aside from reducing quality of life, sequelae of the disease may include pain and disfigurement, possibly leading to more serious physical and occupational limitations. Dermatologists, Podiatrists, and other clinicians who treat onychomycosis are now entering a new era when considering treatment options-topical modalities are proving more effective than those of the past. The once sought after concept of viable, effective, well-tolerated, and still easy-to-use monotherapy alternatives to oral therapy treatments for onychomycosis is now within reach given recent study data. In addition, these therapies may also find a role in combination and maintenance therapy; in order to treat the entire disease the practitioner needs to optimize these topical agents as sustained therapy after initial clearance to reduce recurrence or re-infection given the nature of the disease.
Collapse
Affiliation(s)
- Jenna N Queller
- Dermatology Chief Resident at Harbor-UCLA Medical Center, Torrance, CA 90502, USA.
| | - Neal Bhatia
- Director of Clinical Dermatology, Therapeutics Clinical Research, San Diego, CA 92123, USA.
| |
Collapse
|
28
|
Elsayed MMA. Development of topical therapeutics for management of onychomycosis and other nail disorders: a pharmaceutical perspective. J Control Release 2014; 199:132-44. [PMID: 25481439 DOI: 10.1016/j.jconrel.2014.11.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 11/14/2014] [Accepted: 11/17/2014] [Indexed: 10/24/2022]
Abstract
The human nail plate is a formidable barrier to drug permeation. Development of therapeutics for management of nail diseases thus remains a challenge. This article reviews the current knowledge and recent advances in the field of transungual drug delivery and provides guidance on development of topical/ungual therapeutics for management of nail diseases, with special emphasis on management of onychomycosis, the most common nail disease. Selection of drug candidates, drug delivery approaches, and evaluation of formulations are among the topics discussed. A comprehensive mathematical description for transungual permeation is also introduced.
Collapse
Affiliation(s)
- Mustafa M A Elsayed
- Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, El-Khartoum Square, El-Azarita, Alexandria 21521, Egypt.
| |
Collapse
|
29
|
Tavaborole, a Novel Boron-Containing Small Molecule for the Topical Treatment of Onychomycosis, Is Noncarcinogenic in 2-Year Carcinogenicity Studies. Int J Toxicol 2014; 33:419-27. [DOI: 10.1177/1091581814545245] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Tavaborole, a cyclized boronic acid, has been approved by the Food and Drug Administration for the topical treatment of toenail onychomycosis. This novel, low-molecular-weight pharmaceutical compound has broad-spectrum antifungal activity against dermatophytes, yeasts, and molds responsible for the disease. Tavaborole was tested in 2-year carcinogenicity studies in mice (once daily dermal administration) and rats (once daily by oral gavage) as part of the extensive nonclinical safety program. There was no evidence of tavaborole-related neoplasms observed in either study. Based on the data gathered from these 2 carcinogenicity studies, tavaborole is considered noncarcinogenic.
Collapse
|
30
|
Abstract
A non-lacquer 10% topical solution of efinaconazole, developed by Valeant Pharmaceuticals International, received its first global approval in Canada in October 2013 for the treatment of onychomycosis. The product is under regulatory review in the US and Japan. The mechanism of anti-fungal activity of efinaconazole, a small-molecule triazole compound, appears to be similar to that of other anti-fungal triazoles, namely ergosterol synthesis inhibition. In particular, it appears to inhibit 14α demethylase, an enzyme involved in the conversion of lanosterol to ergosterol, resulting in secondary degenerative changes. This article summarizes the milestones in the development of efinaconazole leading to this first approval for onychomycosis.
Collapse
|
31
|
Affiliation(s)
- Mahmoud Ghannoum
- Center for Medical Mycology, University Hospitals of Cleveland, Cleveland, Ohio, United States of America
- * E-mail:
| | - Nancy Isham
- Center for Medical Mycology, University Hospitals of Cleveland, Cleveland, Ohio, United States of America
| |
Collapse
|
32
|
Gupta AK, Daigle D. Tavaborole (AN-2690) for the treatment of onychomycosis of the toenail in adults. Expert Rev Anti Infect Ther 2014; 12:735-42. [DOI: 10.1586/14787210.2014.915738] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Aditya K Gupta
- Department of Medicine, University of Toronto,
Toronto, Ontario, Canada
- Mediprobe Research Inc.,
London, Ontario, Canada
| | | |
Collapse
|
33
|
Abstract
INTRODUCTION Onychomycosis causes approximately one-half of all nail disorders and its prevalence has been steadily increasing. It is difficult to treat, partly due to the subungual location and the inability of both oral and topical antifungals to reach the site of infection. Published cure rates with oral drugs are < 50% and even lower with topical drugs. Pathogenic factors include the diversity of fungal organisms and the difficulty of drugs penetrating the nail plate. Tavaborole is a broad-spectrum oxaborole antifungal agent with low molecular weight, permitting optimal nail plate penetration. In vitro and ex vivo studies have demonstrated the superior nail-penetrating properties of tavaborole compared to existing topical antifungal medications approved for the treatment of onychomycosis. AREAS COVERED The clinical characteristics and prevalence of onychomycosis, currently available treatments, and the chemistry, safety and pharmacokinetic properties of tavaborole for the treatment of onychomycosis. EXPERT OPINION Tavaborole is a novel, topical antifungal pharmaceutical agent pending FDA approval for the treatment of toenail onychomycosis due to dermatophytes. Efficacy has been demonstrated by a clinical development program including in vitro data and two large Phase III trials that enrolled ∼ 1200 patients. When approved, tavaborole topical solution, 5% may become a safe and effective option for the treatment of onychomycosis.
Collapse
Affiliation(s)
- Boni E Elewski
- University of Alabama, Department of Dermatology , EFH 414, 1530 3rd Avenue South, Birmingham, AL 35294-0009 , USA +1 205 934 5188 ;
| | | |
Collapse
|
34
|
Liu CT, Tomsho JW, Benkovic SJ. The unique chemistry of benzoxaboroles: current and emerging applications in biotechnology and therapeutic treatments. Bioorg Med Chem 2014; 22:4462-73. [PMID: 24864040 DOI: 10.1016/j.bmc.2014.04.065] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/21/2014] [Accepted: 04/30/2014] [Indexed: 12/25/2022]
Abstract
Benzoxaboroles have garnered much attention in recent years due to their diverse applications in bio-sensing technology, material science, and therapeutic intervention. Part of the reason arises from the benzoxaboroles' unique chemical properties, especially in comparison to their acyclic boronic acid counterparts. Furthermore, the low bio-toxicity combined with the high target specificity associated with benzoxaboroles make them very attractive as therapeutic agents. Herein, we provide an updated summary on the current knowledge of the fundamental chemical reactivity of benzoxaboroles, followed by highlighting their major applications reported to date.
Collapse
Affiliation(s)
- C Tony Liu
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, United States
| | - John W Tomsho
- Department of Chemistry & Biochemistry, University of the Sciences, 600 S. 43rd Street, Philadelphia, PA 19104-4495, United States.
| | - Stephen J Benkovic
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, United States.
| |
Collapse
|
35
|
Scher RK, Nakamura N, Tavakkol A. Luliconazole: a review of a new antifungal agent for the topical treatment of onychomycosis. Mycoses 2014; 57:389-93. [PMID: 24621346 DOI: 10.1111/myc.12168] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 12/11/2013] [Indexed: 11/30/2022]
Abstract
Luliconazole is a novel, broad-spectrum, imidazole antifungal under development in the USA as a treatment for dermatophytic skin and nail infections. In vitro, luliconazole is one of the most potent antifungal agents against filamentous fungi including dermatophytes. Luliconazole has been formulated in a 10% solution with unique molecular properties, which allow it to penetrate the nail plate and rapidly achieve fungicidal levels in the nail unit. These properties make luliconazole a potent compound in the treatment of onychomycosis. This article reviews the development of luliconazole solution, 10% its molecular properties, preclinical and clinical data and its future perspectives for the treatment of fungal infections.
Collapse
Affiliation(s)
- Richard K Scher
- Weill Cornell Medical College, Cornell Medical School, New York, NY, USA
| | | | | |
Collapse
|
36
|
Akama T, Virtucio C, Dong C, Kimura R, Zhang YK, Nieman JA, Sharma R, Lu X, Sales M, Singh R, Wu A, Fan XQ, Liu L, Plattner JJ, Jarnagin K, Freund YR. Structure–activity relationships of 6-(aminomethylphenoxy)-benzoxaborole derivatives as anti-inflammatory agent. Bioorg Med Chem Lett 2013; 23:1680-3. [DOI: 10.1016/j.bmcl.2013.01.072] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 01/12/2013] [Accepted: 01/16/2013] [Indexed: 10/27/2022]
|
37
|
Tomsho JW, Pal A, Hall DG, Benkovic SJ. Ring Structure and Aromatic Substituent Effects on the pK a of the Benzoxaborole Pharmacophore. ACS Med Chem Lett 2012; 3:48-52. [PMID: 24900370 DOI: 10.1021/ml200215j] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 10/19/2011] [Indexed: 01/29/2023] Open
Abstract
In this work, we present an investigation into the physical properties of a unique class of aromatic boronic acids, the benzoxaboroles. Using spectrophotometric methods, the ionization constants of a family of substituted benzoxaboroles are determined. Heterocyclic ring modifications are examined to determine their effects on the ionization of the boronic acid moiety. It is also shown that the substituent effects about the aromatic ring follow a Hammett relationship with the compounds' measured pK a values. Finally, these substituent effects are also shown to extend to the sugar binding properties of these compounds under physiologically relevant conditions. Combined, these data will inform medicinal chemists wishing to tailor the ionization and/or ability of this class of compound to bind diol-containing biomolecules.
Collapse
Affiliation(s)
- John W. Tomsho
- Chemistry Department, The Pennsylvania State University, 104 Chemistry Building,
University Park, Pennsylvania 16802, United States
| | - Arnab Pal
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 Canada
| | - Dennis G. Hall
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2 Canada
| | - Stephen J. Benkovic
- Chemistry Department, The Pennsylvania State University, 414 Wartik Building,
University Park, Pennsylvania 16802, United States
| |
Collapse
|
38
|
Agarwal V, Nair SK. Aminoacyl tRNA synthetases as targets for antibiotic development. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20032e] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
39
|
Elewski B, Pollak R, Ashton S, Rich P, Schlessinger J, Tavakkol A. A randomized, placebo- and active-controlled, parallel-group, multicentre, investigator-blinded study of four treatment regimens of posaconazole in adults with toenail onychomycosis. Br J Dermatol 2011; 166:389-98. [DOI: 10.1111/j.1365-2133.2011.10660.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
40
|
Baker SJ, Tomsho JW, Benkovic SJ. Boron-containing inhibitors of synthetases. Chem Soc Rev 2011; 40:4279-85. [DOI: 10.1039/c0cs00131g] [Citation(s) in RCA: 192] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
41
|
Adamczyk-Woźniak A, Madura I, Velders AH, Sporzyński A. Diverse reactivity of 2-formylphenylboronic acid with secondary amines: synthesis of 3-amino-substituted benzoxaboroles. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.09.091] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
42
|
Discovery of novel orally bioavailable oxaborole 6-carboxamides that demonstrate cure in a murine model of late-stage central nervous system african trypanosomiasis. Antimicrob Agents Chemother 2010; 54:4379-88. [PMID: 20660666 DOI: 10.1128/aac.00498-10] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report the discovery of novel boron-containing molecules, exemplified by N-(1-hydroxy-1,3-dihydrobenzo[c][1,2]oxaborol-6-yl)-2-trifluoromethylbenzamide (AN3520) and 4-fluoro-N-(1-hydroxy-1,3-dihydrobenzo[c][1,2]oxaborol-6-yl)-2-trifluoromethylbenzamide (SCYX-6759), as potent compounds against Trypanosoma brucei in vitro, including the two subspecies responsible for human disease T. b. rhodesiense and T. b. gambiense. These oxaborole carboxamides cured stage 1 (hemolymphatic) trypanosomiasis infection in mice when administered orally at 2.5 to 10 mg/kg of body weight for 4 consecutive days. In stage 2 disease (central nervous system [CNS] involvement), mice infected with T. b. brucei were cured when AN3520 or SCYX-6759 were administered intraperitoneally or orally (50 mg/kg) twice daily for 7 days. Oxaborole-treated animals did not exhibit gross signs of compound-related acute or subchronic toxicity. Metabolism and pharmacokinetic studies in several species, including nonhuman primates, demonstrate that both SCYX-6759 and AN3520 are low-clearance compounds. Both compounds were well absorbed following oral dosing in multiple species and also demonstrated the ability to cross the blood-brain barrier with no evidence of interaction with the P-glycoprotein transporter. Overall, SCYX-6759 demonstrated superior pharmacokinetics, and this was reflected in better efficacy against stage 2 disease in the mouse model. On the whole, oxaboroles demonstrate potent activity against all T. brucei subspecies, excellent physicochemical profiles, in vitro metabolic stability, a low potential for CYP450 inhibition, a lack of active efflux by the P-glycoprotein transporter, and high permeability. These properties strongly suggest that these novel chemical entities are suitable leads for the development of new and effective orally administered treatments for human African trypanosomiasis.
Collapse
|
43
|
Adamczyk-Woźniak A, Cyrański MK, Jakubczyk M, Klimentowska P, Koll A, Kołodziejczak J, Pojmaj G, Zubrowska A, Zukowska GZ, Sporzyński A. Influence of the substituents on the structure and properties of benzoxaboroles. J Phys Chem A 2010; 114:2324-30. [PMID: 20092259 DOI: 10.1021/jp9086283] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Benzoxaboroles possessing aryl substituents in the oxaborole ring were synthesized, and their structures were determined by single-crystal X-ray diffraction. Structures in the solid state are centrosymmetric dimers with two intermolecular hydrogen bonds. These compounds were investigated using a combination of the spectroscopic and the computational approach, comparing their properties with the unsubstituted compound. Investigated compounds were characterized by (1)H, (13)C, and (11)B NMR spectroscopy in solution. Assignment of (1)H and (13)C signals was made on the basis of HSQC and HMBC spectra. The molecular structure of 1,3-dihydro-1-hydroxy-3-phenyl-2,1-benzoxaborole was calculated by the density functional (B3LYP) method with the extended 6-311++G(d,p) basis set. The calculated geometrical parameters were compared with experimental X-ray data, and the differences between experimental and calculated values were found to be of the order of experiment standard deviation, confirming a good description by this level of theory. The harmonic frequencies, potential energy distribution (PED), and IR intensities of this compound and its deuterated analogue were calculated with the B3LYP method. The assignment of the experimental spectra was made on the basis of the calculated PED. The consequence of dimer formation is the splitting of the vibrational modes into symmetric and antisymmetric vibrations. The structure modification resulting from the hydrogen bonded dimers formation is presented.
Collapse
|
44
|
Adamczyk-Woźniak A, Cyrański MK, Żubrowska A, Sporzyński A. Benzoxaboroles – Old compounds with new applications. J Organomet Chem 2009. [DOI: 10.1016/j.jorganchem.2009.07.022] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
45
|
NB-002, a novel nanoemulsion with broad antifungal activity against dermatophytes, other filamentous fungi, and Candida albicans. Antimicrob Agents Chemother 2009; 53:3273-9. [PMID: 19433562 DOI: 10.1128/aac.00218-09] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
NB-002 is an oil-in-water emulsion designed for use for the treatment of skin, hair, and nail infections. The activity of NB-002 was compared to the activities of the available antifungal drugs against the major dermatophytes responsible for cutaneous infections, Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, and Microsporum spp., as well as 12 other genera of filamentous fungi. NB-002 consistently displayed fungicidal activity against all dermatophytes. The comparator compounds were either fungistatic or fungicidal, and for some strain-drug combinations, tolerance was observed. Assessment of the development of spontaneous resistance to NB-002 in different dermatophyte species yielded few stably resistant mutants. For filamentous nondermatophyte fungi, the MIC range varied from 0.06 to 0.5 microg/ml for Alternaria spp. to 2 to 8 microg/ml for Paecilomyes spp. NB-002 had activity against both azole-susceptible and -resistant Candida albicans yeast isolates, with MIC(90)s of 2 microg/ml, respectively, and minimum fungicidal concentrations at which 90% of isolates are inhibited of 4 and 8 microg/ml, respectively. The kinetics of the fungicidal activity of NB-002 against T. rubrum isolates were compared to those of the other antifungal drugs. NB-002 killed both mycelia and microconidia even when the fungal forms were dormant or not actively growing. Electron micrographs of mycelia and spores treated with NB-002 showed the significant disruption of the fungal structure. The in vitro broad coverage of NB-002 against filamentous fungi, dermatophytes, and C. albicans, as well as its rapid fungicidal activity, warrants further investigations to ascertain if NB-002 would be useful for the treatment of cutaneous mycoses.
Collapse
|
46
|
Kumar S, Kimball AB. New antifungal therapies for the treatment of onychomycosis. Expert Opin Investig Drugs 2009; 18:727-34. [DOI: 10.1517/13543780902810352] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
47
|
Seiradake E, Mao W, Hernandez V, Baker SJ, Plattner JJ, Alley MRK, Cusack S. Crystal structures of the human and fungal cytosolic Leucyl-tRNA synthetase editing domains: A structural basis for the rational design of antifungal benzoxaboroles. J Mol Biol 2009; 390:196-207. [PMID: 19426743 DOI: 10.1016/j.jmb.2009.04.073] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 04/05/2009] [Accepted: 04/20/2009] [Indexed: 10/20/2022]
Abstract
Leucyl-tRNA synthetase (LeuRS) specifically links leucine to the 3' end of tRNA(leu) isoacceptors. The overall accuracy of the two-step aminoacylation reaction is enhanced by an editing domain that hydrolyzes mischarged tRNAs, notably ile-tRNA(leu). We present crystal structures of the editing domain from two eukaryotic cytosolic LeuRS: human and fungal pathogen Candida albicans. In comparison with previous structures of the editing domain from bacterial and archeal kingdoms, these structures show that the LeuRS editing domain has a conserved structural core containing the active site for hydrolysis, with distinct bacterial, archeal, or eukaryotic specific peripheral insertions. It was recently shown that the benzoxaborole antifungal compound AN2690 (5-fluoro-1,3-dihydro-1-hydroxy-1,2-benzoxaborole) inhibits LeuRS by forming a covalent adduct with the 3' adenosine of tRNA(leu) at the editing site, thus locking the enzyme in an inactive conformation. To provide a structural basis for enhancing the specificity of these benzoxaborole antifungals, we determined the structure at 2.2 A resolution of the C. albicans editing domain in complex with a related compound, AN3018 (6-(ethylamino)-5-fluorobenzo[c][1,2]oxaborol-1(3H)-ol), using AMP as a surrogate for the 3' adenosine of tRNA(leu). The interactions between the AN3018-AMP adduct and C. albicans LeuRS are similar to those previously observed for bacterial LeuRS with the AN2690 adduct, with an additional hydrogen bond to the extra ethylamine group. However, compared to bacteria, eukaryotic cytosolic LeuRS editing domains contain an extra helix that closes over the active site, largely burying the adduct and providing additional direct and water-mediated contacts. Small differences between the human domain and the fungal domain could be exploited to enhance fungal specificity.
Collapse
Affiliation(s)
- Elena Seiradake
- European Molecular Biology Laboratory, Grenoble Outstation rue Jules Horowitz, France
| | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
Many functional, demographic, and immunologic changes associated with aging are responsible for increasing the incidence and severity of infectious diseases in the elderly. Management is complicated by age-related organ system changes. Because many of the elderly are on multiple medications for underlying illnesses, antimicrobial therapy needs to be chosen keeping drug interactions and adverse events in mind. Common infections seen in the elderly are infections of skin and soft tissue, urinary tract, respiratory tract, and gastrointestinal tract. Organized and well-funded programs to address infectious disease issues in the elderly are the only way to improve care.
Collapse
Affiliation(s)
- Tin Han Htwe
- Division of Infectious Diseases, Southern Illinois University School of Medicine, Post Box 19636, Springfield, IL 62794-9636, USA
| | | | | | | | | |
Collapse
|
49
|
Boron. J Diet Suppl 2008; 5:62-94. [DOI: 10.1080/19390210802329352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
50
|
Crépin T, Cusack S. [Trap the product to specifically inhibit the enzyme]. Med Sci (Paris) 2007; 23:1087-9. [PMID: 18154708 DOI: 10.1051/medsci/200723121087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|