In vitro activity of cinnamaldehyde on Leishmania (Leishmania) amazonensis.

Tegumentary leishmaniasis is an endemic disease that urgently needs new and effective treatments. L. amazonensis is one of the main species involved in the transmission of this infectious and non-contagious disease. The currently available treatments for leishmaniasis have high toxicity and vary in efficacy. Natural compounds have been used as alternative therapies for various other diseases, often presenting excellent results with little or no adverse reaction. Cinnamaldehyde is the primary compound of essential oil from cinnamon bark; it is used in the cosmetic, pharmaceutical, and food industries for its antimicrobial and anti-inflammatory effects, as shown in the literature. As far as we know, no studies have evaluated cinnamaldehyde activity against L. amazonensis. In this context, we investigated the anti-Leishmania potential of cinnamaldehyde against promastigote and amastigote forms of L. amazonensis; cytotoxicity in erythrocytes, HaCat cells, and macrophages J774A.1; and its ability to stimulate nitric oxide. Cinnamaldehyde showed anti-Leishmania activity, with an average IC50 of approximately 212 µM against promastigote forms of L. amazonensis (three study periods: 24, 48, and 72 h) and an IC50 of 398.06 ± 42.10 µM against amastigote forms of L. amazonensis. Considerable toxicities to human erythrocytes and HaCat cells were not recorded from treatments with 4000 µM and 1000 µM of cinnamaldehyde, respectively. However, we recorded cytotoxicity with J774A.1 macrophages (0.48-1000 µM), which resulted in a low therapeutic selectivity index. The compound did not alter the production of nitric oxide in the cells evaluated. Overall, we observed that cinnamaldehyde showed anti-Leishmania activity and moderate toxicity. We encourage further research into the use of cinnamaldehyde to treat cutaneous leishmaniasis.

In vivo efficacy of meglumine antimoniate-loaded nanoparticles for cutaneous leishmaniasis: a systematic review.

Background: Nanotechnology is a promising strategy to improve existing antileishmanial agents. Objective: To explore the evidence of encapsulated meglumine antimoniate for cutaneous leishmaniasis treatment in animal models. Materials & methods: The studies were recovered from PubMed, Scopus, EMBASE, LILACS, WoS and Google according to eligibility criteria following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Population, Intervention, Comparison, Outcomes and Study design (PICOS) strategy. Study appraisal was assessed using the Animal Research Reporting of In Vivo Experiments, SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) recommendations. Results: Five studies were included. Liposomes, metallic and polymeric nanoparticles were tested in BALB/c mice against Leishmania major, L. tropica or L. amazonensis. Limitations: Few studies were found to meet the eligibility criteria. Conclusion: All formulations had a significant efficacy, similar to the meglumine antimoniate reference treatment concerning the lesion size and parasite burden. The studies had a high and moderate risk of bias, and the confidence in cumulative evidence was considered low. Therefore, we encourage the development of high-quality preclinical studies. Registration: PROSPERO register CRD42020170191.

Photodynamic therapy in wound healing in vivo: a systematic review.

Wounds constitute severe problems in public health. Inappropriate manipulation to promote wound healing and indiscriminate use of antibiotics may contribute to failure in wound treatment, leading to bacterial growth and resistance. Appropriate and correct approaches to wound treatment are crucially important. Further, the development of new and effective treatment modalities is important to decrease infection-related mortality and to reduce patient suffering and side effects. Photodynamic therapy (PDT) could be a promising approach to ameliorate this global health problem. We researched articles that used PDT in wound healing in vivo. The systematic review included articles that investigated the effect of PDT on wound healing in animals, published from May 2008 through 2018, in the databases PubMed and Web of Science. The main types of wounds described in the selected articles were burns, abrasions, and excisional wounds. Most of the studies tested PDT in wounds infected by methicillin-resistant Staphylococcus aureus, S. aureus standard strain, or Pseudomonas aeruginosa. The studies demonstrated that PDT contributes in several ways to the wound healing process, such as killing bacterial cells and stimulating the proliferation of fibroblasts and consequently of collagen and elastin. Based on these studies, PDT provided excellent results for the wound healing process, acting in several steps and accelerating tissue repair. PDT has proven to be a promising therapeutic modality, able to inhibit bacterial regrowth or kill bacteria, contributing significantly to accelerate the wound healing process.

Variables associated with the post-treatment healing of lesions in patients with American cutaneous leishmaniasis in Paraná state, Brazil / As variáveis associadas com a cicatrização pós-tratamento de lesões em pacientes com leishmaniose tegumentar americana no estado do Paraná, Brasil

The purpose of this study was to investigate the relationship of several variables to the healing of lesions in patients with American cutaneous leishmaniasis (ACL). The patients with clinical and/or laboratorial diagnoses of the disease were followed up for varying periods after treatment by clinical evaluation and indirect immunofluorescence assay (IFA), from September 2000 to December 2003. The lesions of 85.3 percent of the 163 patients had healed by their last return for clinical evaluation, and of these, 82.7 percent had negative IFA results, indicating an association between the healing of lesions and IFA negativity (p=0.000). In patients evaluated up to 120 days after treatment, there was a significant association between negative IFA results and the healing of lesions (p=0.0000). Logistic regression analysis showed that negative IFA results on patients' first return after treatment predicted a 2.175 fold greater chance of lesion healing (p=0.0001). These results indicate an association between IFA negativity at the first return up to a period of 120 days, and the healing of lesions, and that the chances of healing are significantly higher in patients with negative IFA results at their first return after treatment.

O objetivo deste estudo foi investigar a associação de algumas variáveis para a cicatrização de lesões em pacientes com leishmaniose tegumentar americana (LTA). Os pacientes com diagnóstico clínico e laboratorial foram acompanhados depois do tratamento por avaliação clínica e reação de imunofluorescência indireta (IFI), de setembro de 2000 a dezembro de 2003. Dos 163 pacientes 85,3 por cento apresentaram cicatrização das lesões no último retorno para a avaliação clínica e 82,7 por cento destes tiveram a IFI negativa indicando uma associação entre a cicatrização das lesões e a negativação da IFI (p=0,000). Nos pacientes acompanhados até 120 dias depois do tratamento houve associação significativa entre os resultados negativos da IFI e a cicatrização das lesões (p=0,0000). A análise pela regressão logística mostrou que quando a IFI do primeiro retorno após o tratamento foi negativa, o paciente tinha 2,175 mais chance de cicatrização (p=0,0001). Os resultados mostram associação entre a negativação da IFI e a cicatrização das lesões quando o primeiro retorno foi até 120 dias e que as chances de cicatrização são significativamente maiores nos pacientes que apresentaram IFI negativa no primeiro retorno depois do tratamento.