First molecular identification of Leishmania species in a new endemic area of cutaneous leishmaniasis in Lorestan, Iran

Cutaneous leishmaniasis in Iran: A review of epidemiological aspects, with emphasis on molecular findings

Leishmania parasites can cause zoonotic cutaneous leishmaniasis (CL) by circulating between humans, rodents, and sandflies in Iran. In this study, published data were collected from scientific sources such as Web of Science, Scopus, PubMed, Springer, ResearchGate, Wiley Online, Ovid, Ebsco, Cochrane Library, Google scholar, and SID. Keywords searched in the articles, theses, and abstracts from 1983 to 2021 were cutaneous leishmaniasis, epidemiology, reservoir, vector, climatic factors, identification, and Iran. This review revealed that CL was prevalent in the west of Iran, while the center and south of Iran were also involved in recent years. The lack of facilities in suburban regions was an aggravating factor in the human community. Some parts of southern Iran were prominent foci of CL due the presence of potential rodent hosts in these regions. Rhombomys opimus, Meriones lybicus, and Tatera indica were well-documented species for hosting the Leishmania species in Iran. Moreover, R. opimus has been found with a coinfection of Leishmania major and L. turanica from the northeast and center of Iran. Mashhad, Kerman, Yazd, and sometimes Shiraz and Tehran foci were distinct areas for L. tropica. Molecular identifications using genomic diagnosis of kDNA and ITS1 fragments of the parasite indicated that there is heterogeneity in leishmaniasis in different parts of the country. Although cutaneous leishmaniasis has been a predicament for the health system, it is relatively under control in Iran.

Highly sensitive nested polymerase chain reaction to improve the detection of Leishmania species in clinical specimens

Cutaneous leishmaniasis (CL) is one of the most neglected tropical diseases and an important health problem in many countries. It is an endemic disease in most regions of Iraq, while being non-endemic in the Kurdistan Region. The techniques frequently used for detection of CL are not very sensitive. Therefore, this study aimed to identify a sensitive method for diagnosis of CL in clinical samples. The present study was performed in December 2019 to December 2020 in Kalar General Hospital. Clinical samples were collected from 85 suspected CL cases. Sixty-four (75.29%), 71 (83.53%) and 84 (98.82%) cases were detected as positive for CL by microscopy, PCR, and nested PCR, respectively. Of the 84 nested PCR-confirmed CL patients, 46 (54.8%) were female and 38 (45.2%) were male. The most predominate rate of infection was in the 30-39-year age group (29.76%) and the lowest was in the ≥ 60-year group (3.57%). Forty (47.62%) patients had a single lesion. The statistical analysis showed significant differences between age groups and between the number of lesions. The sensitivities of microscopy, conventional PCR, and nested PCR were 80.77%, 86.6% and 100%, respectively, while all three methods showed 100% specificity. Furthermore, PCR-ITS1 followed by a simple restriction fragment length polymorphism (RFLP) analysis using HaeIII endonuclease indicated that Leishmania major was responsible for all CL infections in the study area.

The Geographical Distribution of Human Cutaneous and Visceral Leishmania Species Identified by Molecular Methods in Iran: A Systematic Review With Meta-Analysis

Leishmaniasis is one of the most common vector-borne parasitic diseases in Iran. Leishmania species identification is necessary for epidemiological aspects, precise prognosis, control and treatment of the disease. We systematically searched all the studies, reports, and documentation related to species identification and geographical distribution of causative agents of cutaneous (CL), mucosal (ML), and visceral leishmaniasis (VL) using DNA-based molecular diagnostic techniques in Iran. International databases including PubMed, ScienceDirect, Embase, Google Scholar, Scopus, and Web of Science were systemically searched for English articles and Iran's databases including SID, IranMedex and Magiran were searched for Persian reports and articles. Searches were performed from 1999 to 2019 (20 years). The current review was conducted using the keywords: cutaneous leishmaniasis, visceral leishmaniasis, Leishmania species, Human, Molecular, PCR, and Iran. The study quality was evaluated using the NOS checklist. This meta-analysis procedure was accomplished using STATA, version 2.7.9. Of the 3,426 records identified in the initial search, 154 articles met inclusion criteria and qualified for the systematic review and meta-analysis. In subgroup analysis, the pooled frequency of causative agents of CL isolates was 67.3% (95% CI: 59.51–74.67%) for L. major and 32.1% (95% CI: 24.72–39.87%) for L. tropica. In addition, the pooled frequency of causative agents of VL isolates was 97.1% (95% CI: 94.6–98.8%) for L. infantum and 2.9% (95% CI: 1.12–5.37%) for L. tropica. The findings of this study showed that the main causative agents of CL and VL in Iran are L. major and L. infantum, respectively. Moreover, kinetoplast DNA (kDNA) and internal transcriber spacer (ITS) were the most used markers for identifying Leishmania species. The current study provides valuable data to encourage and direct researchers as well as public health managers in the comprehensive leishmaniasis control and prevention planning in Iran.

Prevalence of Cutaneous Leishmaniasis in Iran (2000-2016): A Systematic Review and Meta-analysis Study

BACKGROUND AND OBJECTIVE

Cutaneous leishmaniasis (CL) is the most common form of leishmaniasis affecting humans. The purpose of this study was to determine the prevalence and epidemiological features of CL in Iran by a systematic review and meta-analysis.

METHODS

The literature search was performed in the SID, Magiran, IranDoc, PubMed, Scopus, Medlib, as well as the Google Scholar search engine databases to find studies on the prevalence of CL. The reference lists of the found articles were also reviewed to obtain additional relevant articles. Studies that were related to treatment and reservoirs of CL were excluded. Forty-four studies were selected for the final analysis.

RESULTS

Meta-analysis with a random-effects model showed that the prevalence of leishmaniasis in Iran was 77 per 100,000 population. Overall, 60% of the patients were men. Most cases of CL occurred in autumn, and the majority of the patients had one lesion, mostly on hands. The most common age group was 20-30 years.

CONCLUSION

In conclusion, CL is an endemic disease in Iran, and its prevalence is largely affected by geographical locations and regional customs. Appropriate preventing measures should be considered to decrease the incidence of CL in Iran.

Detection of species and molecular typing of Leishmania in suspected patients by targeting cytochrome b gene in Zahedan, southeast of Iran

Aim:

Cutaneous leishmaniasis (CL) is one of the most important health problems that are capable of involving both tropical and subtropical areas, especially in Iran. This cross-sectional study aimed to differentiate the species that are able to cause CL in Zahedan city by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Materials and Methods:

It was conducted on 145 suspected CL patients in Zahedan city between 2014 and 2016. The smears were initially prepared, air-dried, fixed with absolute methanol, and stained with 10% Giemsa. Then, we examined the stained samples by a light microscope under 1000× magnifications. PCR assay targeted cytochrome b(cyt b) gene using LCBF1 and LCBR2 primers and the products digested by Ssp1 enzymes.

Results:

From 145 suspected CL patients, 76 (52.4%) were positive in microscopic examination. In addition, we detected gene of interest (cyt b) in 98 (67.5%). The results of PCR-RFLP indicated that 53/98 (54%) cases were Leishmania major and 45/98 (46%) were Leishmania tropica, and the main species in these areas was L. major.

Conclusion:

We concluded that the microscopic examination is not sensitive enough and is not able to distinguish between different Leishmania species. Instead, molecular methods like PCR-RFLP can be appropriately used with promising results.

Olive (Olea europaea) leaf extract alters the cytokine profile of Leishmania major-infected macrophages: New insight into the underlying mechanism

This study aimed to identify the effects of olive leaf extract (OLE) on IFNγ, TNFα, TGFβ and nitric oxide (NO) resulted from macrophages infected with Leishmania major (L. major) amastigotes in the culture medium. High-performance liquid chromatography (HPLC) was used to analyse the level of Oleuropein in plant extract. To evaluate the immunomodulatory effects of OLE, the isolated BALB/c mice peritoneal macrophages were infected with L. major promastigotes and treated with 6.25, 12.5 and 25 μg/mL concentrations of OLE. To assess the cytokines, supernatants of cell cultures were harvested after 12, 24 and 48 hours. Cytokine production was evaluated by ELISA. Nitrite accumulation in the culture medium was assessed using the Griess reaction. The level of Oleuropein in the extract was 18.45% by HPLC. According to results, the production of IFNγ and TNFα was significantly increased when the infected and/or not infected macrophages with L. major promastigotes were affected by different concentrations of OLE. Conversely, the production of TGFβ was significantly decreased under the same conditions. Furthermore, the colorimetric determination of NO accumulation in the culture medium indicated that OLE has no effect on NO production. The study corroborates the immunomodulatory effects of OLE on L. major-infected macrophages.

Comparison of Molecular, Microscopic, and Culture Methods for Diagnosis of Cutaneous Leishmaniasis

Cutaneous leishmaniasis (CL) is endemic in the northwest of Isfahan province, Iran. Increase in the incidence of the disease in Kashan has made it necessary to find out the best method for diagnosis and molecular characterization of Leishmania species. In the present study, 130 patients suspected to cutaneous leishmaniosis referred to health care centers of Kashan were examined. Serosity of lesion was collected for smear preparation and cultured in Novy-Nicolle-McNeal medium. DNA was extracted from serosity, and Leishmania species was determined by polymerase chain reaction (PCR) and nested PCR using kinetoplast DNA (kDNA) specific primers. The diagnostic criteria of CL were based on the observation of amastigotes in the smear, promastigotes in culture, presence of expected bands in PCR, or nested PCR. Of 130 specimens, 87 (66.9%), 72 (56.2%), 98 (75.4 %), 96 (73.8%), and 99 (76.2%) were positive for microscopic culture, PCR, nested PCR, and combined PCR and microscopy (proposed method), respectively. Sensitivity, specificity, positive and negative predictive values of PCR were 99%, 100%, 100%, 96.9%, respectively, for microscopy 87.9%, 100%, 100%, 72.1%, for culture 72.7%, 100%, 100%, 53.4 %, and for nested PCR 97%, 100%, 100%, 91.2%, respectively. Based on the results of the study, kDNA-PCR was the most sensitive method for diagnosis of CL.

Antileishmanial, antioxidant, and cytotoxic activities of Quercus infectoria Olivier extract

Currently, there is no effective vaccine available, and chemotherapy is the main approach for treatment of cutaneous leishmaniasis (CL). During recent decades, studies have demonstrated that a number of plant-derived compounds may act as new therapeutic tools against leishmaniasis. This study was evaluated the antileishmanial, antioxidant, and cytotoxic activities of Quercus infectoria Olivier (oak) extract. The total amount of phenolic and flavonoid compounds was measured in oak extract. High performance liquid chromatography (HPLC) analysis was also performed to determine the amount of quercetin and gallic acid in this plant. This extract (0-80g/mL) was evaluated in vitro against promastigote and intracellular amastigote forms of Leishmania major (MRHO/IR/75/ER) using MTT assay and in a macro-phage model, respectively. Then oak extract was tested on CL in infected male BALB/c mice with L. major in order to evaluate the antileishmanial activity topically. Moreover, cytotoxicity effects of oak in murine macrophage cells were tested by MTT assay. Antioxidative activity of oak was also determined by the 2,2-diphenyl-1,1-picrylhydrazyl (DPPH) scavenging test. The amount of phenolic and flavonoid compounds in the oak extract was 57.50 and 1.86%, respectively. The amount of quercetin and gallic acid in the oak extract was 0.0064 and 0.22%, respectively. The findings revealed that oak significantly (P<0.05) inhibited the growth rate of promastigote of (IC50 12.65μg/mL) and amastigotes (IC50 10.31μg/mL) as a dose-dependent response. In the in vivo assay, after 4 weeks of treatment, 91.6, 66.66, and 50% recovery was observed in the infected mice treated with 20, 10, and 5mg/kg of oak extract, respectively. After treatment of the infected mice with the concentration of 10 and 20mg/kg of oak, the mean diameter of lesions, parasite load and mean number of parasites was significantly (P<0.05) reduced. Selectivity index of greater than 10 for oak revealed that oak extract had no cytotoxic effects on macrophage cells. Moreover, DPPH test demonstrated that radical inhibition occurred at greater power with increasing the concentration of oak. To conclude, the present study showed potent antileishmanial and antioxidant activity of oak extract; whereas this plant had no toxic effect on mammalian cells.

Molecular Diagnosis of Clinical Isolates of Cutaneous Leishmaniasis Using ITS1 and KDNA Genes and Genetic Polymorphism of Leishmania in Kashan, Iran

Cutaneous leishmaniasis is a common skin disease caused by leishmania parasite. An accurate diagnosis of parasites species is possible using molecular techniques. This study was carried out to compare internal transcribed spacer (ITS1) and kinetoplast deoxyribonucleic acid (KDNA) genes for identifying Leishmania species by Polymerase Chain Reaction (PCR), furthermore, genetic diversity of isolates was studied. This research examined 130 patients who were suspected of cutaneous leishmaniasis and referred to Kashan's health centers from 2011-2014. After DNA extraction from serosity, PCR were performed using ITS1 and KDNA primers. Cutaneous Leishmaniasis was diagnosed by the observation of 320 bp band in the ITS1-PCR. The PCR products were digested with restriction enzyme HaeIII and then leishmania species were identified by patterns of enzymatic digestion. The diagnostic criteria of Cutaneous Leishmaniasis (CL) in KDNA-PCR were based on the observation of 760 and 650 bp for Leishmaniasis tropica and Leishmaniasis major, respectively. Twelve isolates of leishmania were sequenced and the phylogenetic tree was traced using the results of sequencing by Mega 4 software. Out of 130 suspected patients to CL, 70 (53.8%) and 98 (75.4%) isolates were positive by Restriction Fragment Length Polymorphism (RFLP) of ITS1 and KDNA, respectively. Using ITS1 PCR, 60 samples (85.7%) and 10 samples (14.3%) were identified as L. tropica and L. major, respectively, ITS1-PCR had 25.3% false negative, compare to microscopy. While, microscopy had false negative in 13 cases compare to KDNA-PCR. Due to the lower sensitivity of the PCR-RFLP of ITS1, KDNA-PCR is recommended for diagnosis of CL. The L. tropica and L. major are the causative agents of CL.

Leishmanicidal, cytotoxicity and wound healing potential of Arrabidaea chica Verlot

BACKGROUND

Leishmaniasis includes a wide complex of diseases that affect humans and other mammals, and can range from a mild cutaneous form to a severe visceral type. The safety of the standard treatment using pentavalent antimony is a concern due to its toxic effects. The search for alternative, effective and less toxic treatments has led to the testing of natural products. The present study aimed to evaluate the cytotoxic, leishmanicidal and healing potential of Arrabidaea chica.

METHODS

The crude ethanolic extract, as well as the chloroform, methanol and ethyl acetate fractions of A. chica were prepared and phytochemical analysis was performed. Cytotoxic evaluation was carried out through MTT colorimetric assay, and the 50% cellular cytotoxicity was determined. After that, the effect of the extract and fractions against Leishmania amazonensis promastigotes, at intervals of 24, 48 and 72 h, was analyzed, and 50% inhibitory concentration was determined. The healing effect of the plant was also tested in surgical lesions in Swiss mice skin.

RESULTS

Phytochemical screening showed that the crude extracts contained flavonoids, tannins, anthocyanidins and chalcones. The leishmanicidal potential of A. chica produced satisfactory results in concentrations of between 60 and 155.9 μg/mL. Cytotoxic assay revealed a 50% reduction in viable cells at a concentration of 189.9 μg/mL. The healing results indicated that the treated group exhibited more pronounced signs of lesion resolution in the early period, but this pattern did not persist throughout the treatment.

CONCLUSIONS

The results of the present study demonstrate that A. chica has cytotoxic and leishmanicidal potential but its healing effect must be better studied.