Interactions between Cationic Vesicles and Candida albicans

Abstract

Dioctadecyldimethylammonium bromide (DODAB), a bilayer-forming synthetic amphiphile with antibacterial properties, also affects viability of Candida albicans. For C. albicans, simultaneous determination of cell viability and electrophoretic mobility as a function of DODAB concentration yields a very good correlation between cell surface charge and cell viability. Upon increasing DODAB concentration, the cell surface charge decreases and changes its sign to yield positively charged cells. However, in contrast to the DODAB bactericidal property, the amphiphile effect on fungus over 1 h of interaction time is only fungistatic at 1 mM DODAB and ca. 10 6 cells/mL. Nevertheless, solubilization of fungicides in DODAB dispersions prepared by sonication causes complete loss of cell viability. Amphotericin B (AB) or miconazole (M) solubilization in the DODAB bilayer leads to 100% cell death, though the drug and DODAB effects are independent. Cell and DODAB bilayer membranes compete for AB or M solubilization with the amphiphile bilayer controlling drug release to the cell membrane. 0.1 mM DODAB plus AB or M concentration of 2 and 20 µg/mL, respectively, yielded 0% of cell viability for C. albicans (2 × 10 6 cells/mL) over an interaction time of 24 h. The cationic liposomes by themselves yielded ca. 20% viability under similar conditions. The full potential of these cytotoxic cationic bilayers to control release and cytotoxicity of drugs remains hitherto unexplored.

Antimicrobial Biomimetics

“…Adsorption of DODAB cationic bilayers onto bacteria cells changes the sign of the cell surface potential from negative to positive, with a clear relationship between positive charge on bacterial cells and cell death (Campanhã et al, 1999). DODAB BF also affected viability of Candida albicans (Campanhã et al, 2001;. Simultaneous determination of C. albicans viability and eletrophoretic mobility as a function of DODAB concentration also yielded good correlation between yeast surface charge and cell viability.…”

“…Another possible mechanism for QACs action might be their inhibition and blockade of potassium channels in Gram-negative bacteria (Raja & Vales, 2009). The positive charge on microbial cells has been often correlated with the biocidal action (Isquith et al, 1972;Endo et al, 1987;Tapias et al, 1994;Sicchierolli et al, 1995;Fidai et al, 1997;Friedrich et al, 2000;Campanhã et al, 2001;Kugler et al, 2005). Dioctadecyldimethylammonium bromide (DODAB) (Tapias et al, 1994;Campanhã et al, 1999;Pereira et al, 2008;Melo et al, 2010), cetyltrimethylammonium bromide (CTAB) Dvoracek et al, 2009) and benzyldimethyldodecylammonium chloride (BDMDAC) (Ferreira et al, 2010) are some examples of quaternary ammonium compounds used to prepare antimicrobial particles.…”

“…Dioctadecyldimethylammonium bromide (DODAB) (Tapias et al, 1994;Campanhã et al, 1999;Pereira et al, 2008;Melo et al, 2010), cetyltrimethylammonium bromide (CTAB) Dvoracek et al, 2009) and benzyldimethyldodecylammonium chloride (BDMDAC) (Ferreira et al, 2010) are some examples of quaternary ammonium compounds used to prepare antimicrobial particles. Supramolecular assemblies of cationic lipid such as the bilayer fragments (BF) or the large bilayer vesicles have already been established as antimicrobial agents (Tapias et al, 1994;Sicchierolli et al, 1995;Martins et al, 1997;Campanhã et al, 1999;Carmona-Ribeiro, 2000;Campanhã et al, 2001;Lincopan et al, 2003;Carmona-Ribeiro, 2003;Carmona-Ribeiro et al, 2006;Vieira & Carmona-Ribeiro, 2008). In particular, DODAB is a cationic bilayer-forming synthetic lipid with a high chemical stability and well-described anti-infective properties .…”

Partículas e filmes híbridos de polímeros e compostos de amônio quaternário com atividade antimicrobiana

“…A quarta geração dos antimicrobianos quaternários inclui diversos sais de mono-e dialquil dimetilamônio e polímeros de amônio quaternário, tais como os ionenos, que são polieletrólitos catiônicos com átomos de nitrogênio na cauda da cadeia polimérica (PETROCCI et al, 1979). As propriedades antimicrobiana, antifúngica e tumoricida dos ionenos indicam que os polímeros são mais ativos do que seus monômeros correspondentes, devido à melhor adsorção do polímero à superfície da célula bacteriana e à membrana citoplasmática, geralmente levando ao subseqüente rompimento da sua integridade (IKEDA & TAZUKE, 1983 (TÁPIAS et al, 1994;SICCHIEROLLI et al, 1995;KANAZAWA et al, 1995;RUSSELL & CHOPRA, 1996;MARTINS et al, 1997;CARMONA-RIBEIRO et al, 1997;CAMPANHÃ et al, 1999;CAMPANHÃ et al, 2001;VIEIRA et al, 2003;PACHECO et al, 2004 (MARINI et al, 2007;PEREIRA et al, 2008).…”

“…Lipossomos catiônicos e outros arranjos supramoleculares com carga positiva já foram estabelecidos como agentes antimicrobianos (VIEIRA & CARMONA- TÁPIAS et al, 1994;SICCHIEROLLI et al, 1995;CAMPANHÃ et al, 2001). Em particular, o DODAB é um lípide catiônico sintético, com grande estabilidade química e propriedades anti-infecciosas bastantes descritas A adesão de vesículas ou a deposição de bicamadas de DODAB ou fosfolipídios sobre superfícies de óxido de silício ou sobre partículas ou filmes poliméricos, na ausência ou presença de polímeros de carga oposta, pode ser uma ferramenta importante para pesquisa e desenvolvimento de biossensores e kits imunológicos (SALAY & CARMONA-RIBEIRO, 1998;SALAY & CARMONA-RIBEIRO, 1999;PEREIRA et al, 2002;PEREIRA et al, 2004 (LU et al, 2005).…”