Leishmaniasis is an infectious disease with various clinical manifestations. We studied the therapeutic effects of Elettaria cardamomum essential oil (ECEO) against Leishmania major infection. In vitro effects of ECEO against L. major were examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and macrophage assays. Nitric oxide (NO) production, infection inhibition in macrophages, and the apoptotic activity of ECEO in treated parasites were also measured. By calculating the 50% cytotoxic concentrations (CC50), we studied the cytotoxicity effects of ECEO on human macrophage cells (THP-1). The efficacy of ECEO for improving cutaneous leishmaniasis (CL) lesions in mice (BALB/c) was determined by evaluating the size of lesions and the number of amastigotes before and after four weeks of treatment. The effects of ECEO on liver and kidney function in the tested mice were also evaluated. ECEO dose-dependently (p<0.001) inhibited the viability and the mean number of promastigotes and amastigote forms of L. tropica. Four weeks of treatment with ECEO at the doses of 2.5 and 5 mg/kg/ day significantly (p<0.001) improved the CL lesions and reduced the number of parasites in the infected mice. ECEO significantly increased NO production, apoptosis induction, and infection rate in parasites. The CC50 value for ECEO and MA was 303.4 µg/mL and 835.2 µg/mL, respectively. In the mice receiving ECEO at the doses of 2.5 and 5 mg/kg/day for 28 days, no significant change was reported between the serum level of liver enzymes and kidney factors when compared with the control group. ECEO displayed promising efficacy in parasite reduction in vitro and in the animal model. ECEO can thus be used as an alternative medicine to treat CL.
We aimed at determination of acaricidal, larvacidal, and repellent activities of green synthesized silver nanoparticles (SNP) against Hyalomma dromedarii as one of the most common ticks in camels. SNP were green synthesized by reducing Lupinus albus extract through the precipitation technique. The acaricidal, larvicidal, and repellent activity of SNP against H. dromedarii was studied through the adult immersion test (AIT), the larval packet test (LPT), the vertical movement behavior of tick's larvae method, anti-acetylcholinesterase (AChE) activity, and oxidative enzyme activity. The green synthesized SNP displayed a spherical form with a size ranging from 25-90 nm; whereas the most distribution of particles size was reported at 50-65 nm. SNP dose-dependently (p<0.001) increased the mortality rate of H. dromedarii adult; whereas at 16 and 32 µg/mL completely killed the adult females. Treatment of exposure of H. dromedarii adult to SNP markedly (p<0.001) declined the mean number, weight, and hatchability of eggs. Treatment of H. dromedarii larvae with SNP reduced the viability rate of larvae with the LC50 and LC90 values of 3.1 and 6.9 µg/mL, respectively. Exposure of H. dromedarii larvae to SNP, especially at ½ LC50 and LC50, markedly (p<0.001) increased the oxidative stress and declined the level of antioxidant enzymes in H. dromedarii larvae; whereas, markedly suppressed the AChE activity of the larvae stage of H. dromedarii in comparison to the control group. These results showed that SNP green synthesized by L. albus extract had promising acaricidal, larvicidal and repellent activity against H. dromedarii adults and larvae as a dose-dependent response. SNP also considrably decreased the level of acetylcholinesterase and antioxidant activity and also provokes oxidative stress in H. dromedarii larvae. However, more investigation must be designed to clear the accurate mechanisms and the efficacy of SNP in practical use.
Knowledge of molecular identification of tick-borne pathogens in camels in Saudi Arabia is very limited; few molecular epidemiological studies have been under taken. This study was to detect Anaplasma spp. and Piroplasma spp. in camels from Asir Province, Saudi Arabia. A total of 150 blood samples were collected from camels in Asir Province and investigated by polymerase chain reaction (PCR) that targeted 18S rRNA and 23S rRNA to detect the DNA of Piroplasma spp. and Anaplasma spp., respectively. The positive samples for 23S rRNA were assayed again by PCR targeting the 16S rRNA. All the blood samples were free from Piroplasma spp. infection. Three camels (2%) were found to be positive for Anaplasma infection through use of PCR that targeted the 23S rRNA gene. There were no significant differences between ages or sexes in the camels that tested positive for Anaplasma. All positive Anaplasma infections were recorded in camels that were infested by ticks. Two Anaplasma sequences for the16S rRNA gene were deposited in GenBank with accession numbers MN882724 and MN882725. They recorded 99.16% and 99.34% similarities (respectively) with KF843825.1 (Candidatus Anaplasma camelii reported in Unizah, Saudi Arabia). Phylogenetic analyses revealed that the two sequences recorded in this study were close to each other; both were located in one cluster with Candidatus Anaplasma camelii isolates that were recorded before in the adjacent areas of Unizah in Saudi Arabia and Iran. In conclusion: two new Anaplasma genotypes close to Candidatus Anaplasma camelii were found in camels in Asir Province, Saudi Arabia for the first time. The camels in this province were found to be free of Piroplasma infection.