Photodynamic therapy controls of Staphylococcus aureus intradermal infection in mice

Abstract

Infections caused by Staphylococcus aureus lead to skin infections, as well as soft tissues and bone infections. Given the communal resistance to antibiotics developed by strains of this bacterium, photodynamic therapy emerges as a promising alternative treatment to control and cure infections. Females of the Balb/C mice were infected with 10 CFU of methicillin-resistant S. aureus (MRSA) and divided into four distinct groups: P-L- (negative control group), P+L- (group exposed only to curcumin), P-L+ (group exposed only to LED incidence of 450 nm, 75 mW/cm, and 54 J/cm for 10 min), and P+L+ (group exposed to curcumin followed by 10 min of LED irradiation) (n = 24). The mice were euthanized 48 and 72 h after infection, and biologic materials were collected for analysis of the bacterial load, peripheral blood leukocyte counts, and draining lymph nodes cell counts. The normalization of data was checked and the ANOVA test was applied. The bacterial load in the draining lymph node of P+L+ group was lower when compared to the control groups 72 h post infection (p < 0.0001), indicating that the LED incidence associated with curcumin controls of the staphylococci intradermal infection. The number of the total lymph node cells shows to be lower than control groups in the two availed times (p < 0.01). The histological analysis and the counting of white blood cells did not show differences among cells in the blood and in the tissue of infection. This is the first report showing that photodynamic therapy may be effective against MRSA infection in a murine model of intradermal infection.

The Anti-Staphylococcal Potential of Ethanolic Polish Propolis Extracts

“…Selection of resistant strains can be limited by combined therapy—simultaneous use of at least two antibiotics/agents that affect different molecular targets [14,15]. Another interesting approach for the treatment of infectious disease is photodynamic therapy [16,17] and some research groups developed new vaccines that seem to be effective in the prophylaxis of staphylococcal infections [18,19,20].…”

Induction of Different Sensitization Patterns of MRSA to Antibiotics Using Electroporation

“…Ermolaeva et al have shown that atmospheric cold plasma causes intracellular damage of S. aureus and allows inactivating bacteria by strong oxidative stress [ 12 ]. As an alternative, the potency of photodynamic therapy was highlighted by Almeida et al and a first report on the efficacy of curcumin showed that photodynamic therapy may be effective against MRSA infections [ 13 ]. Reports on the bioelectric inhibitory effects of low and high frequency electric currents are also available [ 14 , 15 ].…”

“…Reports on the bioelectric inhibitory effects of low and high frequency electric currents are also available [ 14 , 15 ]. Nevertheless, the available methodologies have limitations such as a long time of exposure [ 14 ], the requirement to use photosensitizers [ 13 ] or other undesired side effects [ 16 ]. In this study, we extend the array of effective bacteria inactivation methodologies by providing data on the inactivation efficacy of electroporation in combination with typical antibiotics.…”

Nonconventional Therapeutics against Staphylococcus aureus

“…In parallel with what is observed in vitro, PDT can be highly successful at eradicating S. aureus within the host; however, this is greatly dependent on the photosensitizer, light source, and duration of exposure chosen (183). Nonetheless, PDT has been shown to effectively deplete bacterial levels and decrease wound healing time in superficial skin infections using murine skin abrasion and burn wound models, as well as to reduce bacterial burdens in deeper soft tissue abscesses (184–189). Using fiber optic light delivery systems, PDT treatment has also been quite effective against S. aureus osteomyelitis in rats (190–193).…”