Molecules with antifungal potential on Candida and Cryptococcus and investigation of mechanisms of action: inhibition and cell death

• Grant number: 23/12190-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2024
• End date: February 28, 2026
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Kelly Ishida
• Grantee: Kelly Ishida
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Ângelo de Fátima ; Marcio Vinicius Bertacine Dias
• Associated research grant(s): 24/01974-3 - Role of miltefosine in the interaction of Cryptococcus neoformans with macrophages and in combination therapy with antifungals in a murine model of cryptococcosis, AP.R; 24/02673-7 - Urease: production of recombinant protein and development of inhibitors for antifungal therapy against cryptococcosis, AP.R SPRINT

Abstract

Invasive fungal infections (IFIs) are considered a public health problem that result in high rates of mortality and morbidity. Among the IFIs, Candida albicans represents 50-70% of the cases, followed by Cryptococcus and Aspergillus. However, resistant and emerging species have frequently been isolated, such as Candida auris considered a superbug responsible for outbreaks in hospital on all continents. In addition to resistance to antifungals, limitations such as high toxicity, unfavorable pharmacokinetics, high cost and unavailability further reduce the therapeutic options for fungal infections. Thus, new targets, new molecules and pharmaceutical formulations have been researched in recent years as potential alternatives in the treatment of mycoses. Our research group has investigated antifungal potentials within these three approaches and, therefore, this proposal is a continuation of the regular project previously approved by FAPESP (2021/01279-5), whose goals are to study new targets in C. auris and in C. neoformans and to evaluate antifungal activity of molecules on Candida spp. and Cryptococcus spp. In this regard, in this project we intend to: i) clone, express and purify urease enzyme from C. neoformans (CnURE) using the eukaryotic Pichia pastoris model; ii) solve the structure of CnURE; iii) evaluate the inhibitory effect and molecular interaction of inhibitors with CnURE enzyme; iv) evaluate the fungistatic/fungicidal and antibiofilm effects of synthetic molecules and natural products; v) evaluate the morphophysiological effects caused by the molecules; vi) elucidate the molecular mechanisms and fungal death caused by the molecule; vii) evaluate the toxicity of compounds in cell lines and larval model of Galleria mellonella; and finally, viii) to evaluate the in vivo antifungal effect of the selected compounds using G. mellonella larval model and murine model infected by Candida spp. or Cryptococcus spp. (AU)