An overview of Leishmaniasis with a focus on the island of Cyprus

Antileishmanial activity of Ptilostemon chamaepeuce subsp. cyprius

BACKGROUND

Phytochemicals from unexplored plant species may be vital to unlocking pharmaceutical antibiotic and antiparasitic discoveries. New compounds need to be discovered to combat antimicrobial resistance. This study aimed to investigate ethanolic leaf extracts from five endemic and four indigenous plants from Cyprus for antibacterial, antileishmanial, and antioxidant activities.

METHODS

Ethanolic leaf extracts were screened for antibacterial activity using a broth microdilution assay and iodonitrotetrazolium chloride (INT) as a colourimetric redox indicator for determining the minimum inhibitory concentration (MIC) against four Gram-positive and two Gram-negative American Type Culture Collection (ATCC) reference bacteria. Total phenolic content (TPC), total flavonoid content (TFC) and radical scavenging activity assays were performed to screen for antioxidant potential. Leishmania infantum clinical culture (MCAN/CY/2005/CD57) was used to screen the extracts for in vitro antileishmanial activity. Their cytotoxicity in vitro was assessed using the resazurin fluorometric assay with a HepG2 cell line. As an estimate of in vitro toxicity, a brine shrimp lethality assay was performed.

RESULTS

The ethanol extract of Ptilostemon chamaepeuce subsp. cyprius (Greuter) Chrtek & B. Slavik demonstrated antibacterial activity against Enterococcus faecalis (ATCC 29212) with minimum inhibitory concentration (MIC) < 0.625 mg/mL and antileishmanial activity against a clinical isolate of L.infantum (MCAN/CY/2005/CD57) from an infected dog (promastigote IC50 of 105.7 ± 2.5 μg/mL and amastigote IC50 of 118.5 ± 4.3 μg/mL) after 48 h and compared to the activity of the reference drug, miltefosine (IC50 of 3.7 ± 0.1 μg/mL and 18.5 ± 2.3 μg/mL, respectively). Liquid-chromatography-mass spectrometry (LC-MS) analysis revealed the presence of at least five sesquiterpene lactones (STLs) in P. cham. subsp. cyprius ethanolic extract. The main compound, deacylcynaropicrin, based on its high-resolution mass spectrum, is believed to be primarily responsible for the antileishmanial activity observed in vitro. Quercus alnifolia Poech ethanolic extract showed antibacterial activity against four Gram-positive and one Gram-negative bacteria with MIC values of < 0.625 mg/mL, respectively, and antioxidant capacity in DPPH radical scavenging assay with IC50 of 0.155 ± 0.002 mg/mL and compared to ascorbic acid (IC50 of 0.036 ± 0.000 mg/mL) and Trolox (IC50 of 0.047 ± 0.001 mg/mL).

CONCLUSION

The ethanolic extract of Ptilostemon chamaepeuce subsp. cyprius demonstrated dose-dependent antileishmanial activity. This is the first data report of P.cham. subsp. cyprius and Q.alnifolia ethanolic extracts to indicate antibacterial, antileishmanial and antioxidant activities in preliminary investigations. Moreover, this is the first report on STLs in P. cham. subsp. cyprius, and future studies are needed to confirm if they are responsible for the in vitro antileishmanial activity. These findings highlight the potential of these endemic plants as sources for developing new drugs targeting Gram-positive bacterial infections and leishmaniasis, encouraging further pharmaceutical research.

Knowledge and Attitude Regarding Cutaneous Leishmaniasis Among Adult Population in Tabuk, Saudi Arabia

Background Cutaneous leishmaniasis (CL) is a major health problem in Saudi Arabia. It is caused by the protozoa Leishmania. The vector is female sand flies. In order to develop preventive strategies to reduce the burden of this health problem, public awareness of the disease should be assessed. Objective This study aimed to investigate the knowledge and attitude toward CL among the adult population in Tabuk, Saudi Arabia. Methods A cross-sectional survey study was conducted on 385 adult participants of Tabuk between April and May 2022. The investigators assembled the survey questions from peer-reviewed articles with some modifications. Google Forms was used to create the online survey. Social media were used to distribute the survey. Results The study revealed that hearing about CL was much more common among participants older than 61 years and Saudi males. The most prominent sources of information for the participants on which their answers were based were as follows: families and friends, health care professionals, television or radio, and lastly, newspapers. Subjects older than 61 years also showed more knowledge of the risk factors for contracting CL. However, the participants showed overall poor knowledge of the clinical presentation of the disease, which gender or age group was mostly affected, or how the disease was transmitted. Likewise, their knowledge of sand flies was poor. Most participants did not know if CL was a health problem or not. Conclusions The study revealed overall poor awareness of the epidemiological aspects of CL, how it is transmitted, its clinical presentation, and proper management. Our study could help authorities correct the gap in knowledge regarding CL in Tabuk.

Knock, knock, knocking on Europes door: Threat of leishmaniasis in Europe with a focus on Turkey

Leishmaniasis epidemiology is currently undergoing substantial transformations in both Turkey and Europe, signifying potential implications for public health. This review analyzes the evolving patterns within Turkey and their potential ramifications for Europe. Within Turkey, the dynamics of leishmaniasis are undergoing noteworthy alterations, manifesting in a rise in cutaneous leishmaniasis (CL) cases and the emergence of Leishmania major and Leishmania donovani. These transformations are predominantly driven by factors such as the distribution of vectors, human activities, climate fluctuations, and migration. Across Europe, particularly in countries within the Mediterranean basin, leishmaniasis is endemic, primarily attributed to Leishmania infantum. Recent evidence suggests a resurgence of the disease even in previously non-endemic areas, propelled by climate change, urbanization, and migration. The changing landscape of leishmaniasis in Turkey carries direct implications for Europe. The presence and distribution of Leishmania tropica, L. major, and L. donovani raise concerns regarding cross-border transmission. Turkey's strategic position along migration routes further compounds the risk, alongside the facilitative effects of climate change and host mobility. Embracing a One Health approach with public awareness campaigns should be a priority. To ensure the protection of public health in Europe, it is imperative to adopt a proactive approach by establishing robust surveillance mechanisms, implementing preventive measures, and cultivating collaboration with Turkey. The invaluable experience, strategic geographical location, and well-established infrastructure of Turkey make this collaboration crucial in effectively addressing the evolving dynamics of leishmaniasis and its potential impacts on Europe.