Antileishmanial and Cytotoxic Effects of Essential Oil and Methanolic Extract of Myrtus communis L

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.

Antileishmanial and Cytotoxic Effects of Essential Oil and Methanolic Extract of Myrtus communis L

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.

Overexpression of Ubiquitin and Amino Acid Permease Genes in Association with Antimony Resistance in Leishmania tropica Field Isolates

The mainstay therapy against leishmaniasis is still pentavalent antimonial drugs; however, the rate of antimony resistance is increasing in endemic regions such as Iran. Understanding the molecular basis of resistance to antimonials could be helpful to improve treatment strategies. This study aimed to recognize genes involved in antimony resistance of Leishmania tropica field isolates. Sensitive and resistant L. tropica parasites were isolated from anthroponotic cutaneous leishmaniasis patients and drug susceptibility of parasites to meglumine antimoniate (Glucantime(R)) was confirmed using in vitro assay. Then, complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) and real-time reverse transcriptase-PCR (RT-PCR) approaches were utilized on mRNAs from resistant and sensitive L. tropica isolates. We identified 2 known genes, ubiquitin implicated in protein degradation and amino acid permease (AAP3) involved in arginine uptake. Also, we identified 1 gene encoding hypothetical protein. Real-time RT-PCR revealed a significant upregulation of ubiquitin (2.54-fold), and AAP3 (2.86-fold) (P<0.05) in a resistant isolate compared to a sensitive one. Our results suggest that overexpression of ubiquitin and AAP3 could potentially implicated in natural antimony resistance.

A double blind, randomised placebo controlled trial of rifampicin with omeprazole in the treatment of human cutaneous leishmaniasis.

BACKGROUND & OBJECTIVES: This study was conducted on 50 patients of Anthroponotic cutaneous leishmaniasis (oriental sore) to assess the efficacy of rifampicin and omeprazole through a double blind, randomised placebo control study. METHODS: The diagnosis of Anthroponotic cutaneous leishmaniasis (ACL) caused by Leishmania tropica was done by demonstration of Leishmania tropica (LT) bodies from the painless, dry ulcerative lesion. Each patient was assessed clinically in the beginning of the study, at the end of 2,4 and 6 weeks and all observations were compared in both the groups. Twenty-five patients received rifampicin with omeprazole (Group A) whereas other 25 patients received placebo (Group B) for a period of six weeks. RESULTS: Altogether 23 cases in group Aand 21 cases in group B completed the study. About 16 (69.7%) cases in group A and 3 (14.29%) cases in group B had complete healing, whereas 3 patients (13.04%) of group A and 4 patients (19.05%) of group B had partial response and 4 patients (17.93%) of group A and 14 patients (66.67%) of group B had no response at the end of study. The difference of two groups was statistically highly significant (p < 0.00025). All patients tolerated the drug and placebo very well and no side effect was reported. INTERPRETATION & CONCLUSION: In our opinion rifampicin and omeprazole is a highly effective, less toxic and cheaper alternative for the management of cutaneous leishmaniasis.

Zinc sulphate in the treatment of cutaneous leishmaniasis: in vitro and animal study

This study was designed to evaluate the effectiveness of zinc sulphate both in vitro and in an animal model against both strains of old world cutaneous leshmaniasis. The in vitro sensitivities of promastigotes and axenic amastigotes of both Leishmania major and L. tropica to zinc suphate was determined, the LD50 calculated and compared to the standard treatment for cutaneous leishmaniais pentavalent antimony compounds. The results show that the two forms of both strains were sensitive to zinc sulphate and their respective LD50 were lower compared to the pentavalent antinomy compound. Furthermore the sensitivities of the forms of both strains were tested using a simple slide method and compared to results of the standard method. To confirm this result, zinc sulphate was administered orally to mice infected with cutaneous leishmaniasis both therapeutically and prophylactically. Results showed that oral zinc sulphate was effective in both treatment and prophylaxis for cutaneous leishmaniasis. These results encourage the use of oral zinc sulphate in the treatment of cutaneous leishmaniasis clinically.

preliminary study on the inhibitory action of mystatin on the promastigote forms of leishmania tropica and leishmania infantum isolates of Pakistan

Leishmania is the etiological agent of a group of parasitic disease Leishmaniases. Recent reports show that the disease is on the rise in Pakistan. As no vaccine is yet available for any type of leishmaniasis, chemotherapy is the only means of controlling the disease. As a part of our project to find out new antileishmanial compounds, we have studied the antileishmanial activity of nystatin [mycostatin], a polyene compound, on the promastigote forms of L. tropica and L. infantum isolates of Pakistan. In in vitro cultivation, the EC50 values [the concentration of drug necessary to inhibit the growth rate of cells to 50% of the control value] obtained for Nystatin against the promastigote of L. tropica and L. infantum were 19.5-19.8 iu/ml. The mode of action proposed for this drug is same as for famous leishmanicidal drug Amphotericin B as both of these polyene drugs strongly and selectively binds to the sterols present on the surface of the parasite result in the formation of unusual pores / gaps on the surface that result in the leakage of the ions. This leakage finally leads to the destruction of the cell