Leishmaniasis, a neglected disease caused by Leishmania protozoans, primarily affects people in tropical and subtropical areas. Chemotherapy based on the use of pentavalent antimonials, amphotericin B, paromomycin, miltefosine and liposomal amphotericin B is currently the only effective treatment. However, adverse effects, long-term treatment and the emergence of parasite resistance have led to the search for alternative treatments. Natural products used in traditional medicine provide an unlimited source of molecules for the identification of new drugs, and the Amazon region has abundant biodiversity that includes several species of plants and animals, providing a rich source of new products and compounds. Although the literature describes numerous promising compounds and extracts for combating Leishmania protozoans, the results of such research have not been embraced by the pharmaceutical industry for the development of new drugs. Therefore, this review focused on the antileishmanial activity of extracts, isolated compounds and essential oils commonly used by the local population in the Brazilian Amazonian region to treat several illnesses and described in the literature as promising compounds for combating leishmaniasis.
Animals ; Antiprotozoal Agents ; chemistry ; isolation & purification ; pharmacology ; Brazil ; Humans ; Leishmania ; drug effects ; genetics ; growth & development ; Leishmaniasis ; drug therapy ; parasitology ; Plant Extracts ; chemistry ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry

One of the most common drugs used against a wide variety of anaerobic protozoan parasites is metronidazole. However, this drug is mutagenic for bacteria and is a potent carcinogen for rodents. Thymus vulgaris is used for cough suppression and relief of dyspepsia. Also it has antibacterial and antifungal properties. The aim of this study was to investigate antiamebic effect of Thymus vulgaris against Entamoeba histolytica in comparison with metronidazole. One hundred gram air-dried T. vulgaris plant was obtained and macerated at 25 degrees C for 14 days using n-hexane and a mixture of ethanol and water. For essential oil isolation T. vulgaris was subjected to hydrodistillation using a clevenger-type apparatus for 3 hr. E. histolytica, HM-1: IMSS strain was used in all experiments. It was found that the minimal inhibitory concentration (MIC) for T. vulgaris hydroalcoholic, hexanic extracts, and the essential oil after 24 hr was 4 mg/mL, 4 mg/mL, and 0.7 mg/mL, respectively. After 48 hr the MIC for T. vulgaris hydroalcoholic and hexanic extracts was 3 and 3 mg/mL, respectively. Therefore, it can be concluded that the Iranian T. vulgaris is effective against the trophozoites of E. histolytica.
Animals ; Antiprotozoal Agents/chemistry/*pharmacology ; Dose-Response Relationship, Drug ; Entamoeba histolytica/*drug effects ; Iran ; Metronidazole/pharmacology ; Microbial Sensitivity Tests ; Plant Extracts/chemistry/*pharmacology ; Plant Oils/chemistry/pharmacology ; Thymus Plant/*chemistry

The disinfectant effects (DEs) of 10 types of chemicals, defined by their ability to destroy or inhibit oocysts and consequently prevent sporulation of Eimeria tenella field isolate, were evaluated in vitro. Correct species assignments and sample purities were confirmed by the singular internal transcribed spacer (ITS)-PCR analysis. A total of 18 treatments were performed, and the disinfection suppression levels were 75.9% for 39% benzene + 22% xylene (1:10 dilution), 85.5% for 30% cresol soup (1:1 dilution), and 91.7% for 99.9% acetic acid (1:2 dilution) group. The results indicate that acetic acid, cresol soup, and benzene+xylene are good candidates for suppression of E. tenella oocyst sporulation.
Animals ; Antiprotozoal Agents/*pharmacology ; Cluster Analysis ; DNA, Protozoan/chemistry/genetics ; DNA, Ribosomal Spacer/chemistry/genetics ; Disinfectants/*pharmacology ; Eimeria tenella/*drug effects/*growth & development ; Microscopy ; Molecular Sequence Data ; Parasitic Sensitivity Tests ; Phylogeny ; Sequence Analysis, DNA ; Spores, Protozoan/*drug effects/*growth & development

Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were alpha-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC50 values for essential oil and methanolic extract was 8.4 and 28.9 mug/ml against promastigotes, respectively. These values were 11.6 and 40.8 mug/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC50 values of 88.3 and 44.6 mug/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent.
Animals ; Antiprotozoal Agents/isolation & purification/*pharmacology/toxicity ; Cell Line ; Cell Survival/drug effects ; Cyclohexanols/isolation & purification/pharmacology/toxicity ; Inhibitory Concentration 50 ; Leishmania tropica/*drug effects/physiology ; Macrophages/drug effects ; Mice ; Monoterpenes/isolation & purification/pharmacology/toxicity ; Myrtus/*chemistry ; Oils, Volatile/isolation & purification/*pharmacology/toxicity ; Plant Extracts/isolation & purification/*pharmacology/toxicity

Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were alpha-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC50 values for essential oil and methanolic extract was 8.4 and 28.9 mug/ml against promastigotes, respectively. These values were 11.6 and 40.8 mug/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC50 values of 88.3 and 44.6 mug/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent.
Animals ; Antiprotozoal Agents/isolation & purification/*pharmacology/toxicity ; Cell Line ; Cell Survival/drug effects ; Cyclohexanols/isolation & purification/pharmacology/toxicity ; Inhibitory Concentration 50 ; Leishmania tropica/*drug effects/physiology ; Macrophages/drug effects ; Mice ; Monoterpenes/isolation & purification/pharmacology/toxicity ; Myrtus/*chemistry ; Oils, Volatile/isolation & purification/*pharmacology/toxicity ; Plant Extracts/isolation & purification/*pharmacology/toxicity

This study investigated whether trinitroglycerine (TNG) as nitric oxide (NO) releasing agent had anti-leishmanial effects and mediated pathology in BALB/c mice infected with Leishmania major. Cutaneous leishmaniasis (CL), a zoonotic infection caused by leishmania protozoa is still one of the health problems in the world and in Iran. NO is involved in host immune responses against intracellular L. major, and leishmania killing by macrophages is mediated by this substance. Moreover, application of CL treatment with NO-donors has been recently indicated. In our study, TNG was used for its ability to increase NO and to modify CL infection in mice, in order to evaluate NO effects on lesion size and formation, parasite proliferation inside macrophages, amastigote visceralization in target organs, and NO induction in plasma and organ suspensions. Data obtained in this study indicated that TNG increased plasma and liver-NO, reduced lesion sizes, removed amastigotes from lesions, livers, spleens, and lymph nodes, declined proliferation of amastigotes, hepatomegaly, and increased survival rate. However, TNG reduced spleen-NO and had no significant effects on spelenomegaly. The results show that TNG therapy reduced leishmaniasis and pathology in association with raised NO levels. TNG had some antiparasitic activity by reduction of positive smears from lesions, livers, spleens, and lymph nodes, which could emphasize the role of TNG to inhibit visceralization of L. major in target organs.
Animal Structures/parasitology ; Animals ; Antiprotozoal Agents/chemistry/*therapeutic use ; Female ; Leishmania major/*drug effects/immunology ; Leishmaniasis, Cutaneous ; Macrophages/parasitology ; Mice ; Mice, Inbred BALB C ; Nitric Oxide/blood/metabolism/*pharmacology ; Nitroglycerin/*analogs & derivatives/*therapeutic use ; Severity of Illness Index ; Skin/pathology ; Survival Analysis