Leishmania major Infection in Synanthropic Rodents: Evidence for the Urbanization of Zoonotic Cutaneous Leishmaniasis (ZCL) in Southern Iran.

Cutaneous leishmaniasis is of particular importance in southern Iran. This study aimed to investigate the infection of rodents with Leishmania major in an urban area of Fars Province, located in southern Iran. Rodents were trapped and samples from the liver, spleen, and skin were collected. Impression smears were prepared from these tissues and any skin lesions and were examined microscopically. In addition, a portion of the samples were preserved for subsequent DNA extraction. A total of 41 rodents belonging to three species were caught from 10 trapping stations in gardens or houses within the area. The caught rodent species were Rattus rattus (n = 25, 60.97%), Mus musculus (n = 15, 36.58%), and Meriones persicus (n = 1, 2.5%). Leishmania amastigotes were seen in the spleen tissue smear of 6 (2.43%) of the rodents, including 4 of R. rattus and 2 of M. musculus. Skin lesions were observed on the muzzles of two R. rattus and one M. musculus. Samples taken from these lesions tested positive for Leishmania infection. Leishmania DNA was detected in 18 (43.9%) rodents, including 11 R. rattus, 6 M. musculus, and one M. persicus, based on DNA sequencing of the ITS2 gene and PCR of the kDNA. Phylogenetic reconstruction revealed that the parasite infecting the rodents was L. major. The detection of Leishmania infection in these rodents in urban areas raises concerns about the urbanization of cutaneous leishmaniasis caused by L. major. This urbanization poses unique challenges for control and prevention efforts.

Molecular diagnosis of Trichomonas vaginalis in liquid-based Papanicolaou samples in Shiraz, southern Iran.

BACKGROUND: Trichomoniasis is a parasitic infection of the urinary and genital tract, caused by Trichomonas vaginalis. This study aimed to investigate the molecular diagnosis of T. vaginalis infection in liquid-based Papanicolaou samples in Shiraz, southern Iran. MATERIALS AND METHODS: In this cross-sectional study, 534 liquid-based Papanicolaou samples were collected from women referring to the laboratory of Motahari Clinic of Shiraz University of Medical Sciences in 2021. Genomic DNA were extracted from the samples and examined for evidence of T. vaginalis using polymerase chain reaction (PCR) using TVK3 and TVK7 specific primers. RESULTS: The mean age of participants was 39.28 ± 9.89 with a maximum age of 65 and a minimum age of 19 years. T. vaginalis DNA fragments were detected in 4.86% (26/534) of the cases. There was significantly higher prevalence in the age groups of 21 to 30 and 41 to 50 years (46.15%, p = 0.001 and 38.46%, p = 0.015, respectively). Furthermore, the results showed an association between a history of foamy discharge and Trichomonas positivity (p = 0.001). CONCLUSION: T. vaginalis infection is common in liquid-based Papanicolaou samples of women who attended regular health check-ups in the study area. Screening for trichomoniasis in populations, particularly if using highly sensitive methods such as PCR, may lead to increased detection and treatment.

A machine learning-based system for detecting leishmaniasis in microscopic images.

BACKGROUND: Leishmaniasis, a disease caused by a protozoan, causes numerous deaths in humans each year. After malaria, leishmaniasis is known to be the deadliest parasitic disease globally. Direct visual detection of leishmania parasite through microscopy is the frequent method for diagnosis of this disease. However, this method is time-consuming and subject to errors. This study was aimed to develop an artificial intelligence-based algorithm for automatic diagnosis of leishmaniasis. METHODS: We used the Viola-Jones algorithm to develop a leishmania parasite detection system. The algorithm includes three procedures: feature extraction, integral image creation, and classification. Haar-like features are used as features. An integral image was used to represent an abstract of the image that significantly speeds up the algorithm. The adaBoost technique was used to select the discriminate features and to train the classifier. RESULTS: A 65% recall and 50% precision was concluded in the detection of macrophages infected with the leishmania parasite. Also, these numbers were 52% and 71%, respectively, related to amastigotes outside of macrophages. CONCLUSION: The developed system is accurate, fast, easy to use, and cost-effective. Therefore, artificial intelligence might be used as an alternative for the current leishmanial diagnosis methods.

In vitro evaluation of CRISPR PX-LmGP63 vector effect on pathogenicity of Leishmania major as a primary step to control leishmaniasis.

Cutaneous leishmaniasis (CL) is caused by intracellular obligate parasites (Leishmania spp.) carried by the blood-sucking of female sandflies and transmitted between mammalian hosts. Despite the high incidence and prevalence of Leishmania cases in many countries, it has been a neglected tropical disease. The current treatment approaches are limited by the complications such as loss of fertility and drug resistance. It is, therefore, essential to find new medicines to treat leishmaniasis. CRISPR/Cas9 as a powerful genome-editing tool provides the opportunity to create precise genetic manipulation to investigate the molecular basis of different leishmaniasis cases. Therefore, our main goal was to evaluate the CRISPR PX-LmGP63 vector effect on pathogenicity of Leishmania majorin vitroto challenge for using CRISPR/Cas9 as a therapeutic CL through the reduction of L. major pathogenicity by manipulating the GP63 gene. In this study, L. major parasites were transfected with CRISPR/Cas9 vectors constructed by electroporation and then added to macrophage cells on RPMI. The effect of CRISPR/Cas9 constructs on GP63 mutation, viability, and status of L. major was investigated by counting phagocytic parasites into macrophages and DNA sequence analysis. Our data validate that the use of CRISPR/Cas9 in L. major creates a new stop codon and disrupts the frame sheet of the gene by creating a new insertion (thymine), which prevents its expression. In addition, the parasite count was significantly different in the case and control of infected macrophages (P < 0.05). This study shows the successfully targeted manipulation of the L. major GP63 gene via the adaptation of the CRISPR/Cas9 editing tool. The manipulation of GP63 revealed a reduction in the infection load compared to wild-type parasite infection. Therefore, more studies are necessary for this field to help achieve a new method for the prevention and treatment of CL disease.

Comparison of real-time PCR and nested PCR for toxoplasmosis diagnosis in toxoplasmic retinochoroiditis patients.

BACKGROUNDS: PCR is a proper technique that significantly improves toxoplasmosis diagnosis. However, a more sensitive technique is required. This study compared real-time PCR with nested PCR using B1, SAG-4, and MAG-1 bradyzoite genes to diagnose toxoplasmosis in toxoplasmic retinochoroiditis patients. METHODS: Blood samples were collected from 10 patients with active toxoplasmic chorioretinal lesions and 10 healthy individuals. Blood samples including peripheral blood mononuclear cells (PBMCs), serum and whole blood samples were used for DNA extraction. Serum was also used to detect anti-toxoplasma IgG and IgM antibodies. Nested PCR and real-time PCR were performed using B1, SAG-4, and MAG-1 target genes. RESULTS: Five (50%) out of the 10 patients were tested positive for toxoplasmosis with nested PCR using the PBMC samples. All the five patients tested positive with nested PCR were also tested positive for toxoplasmosis with real-time PCR using the PBMC samples. The real-time PCR results demonstrated that 9(90%) out of the 10 patients were positive based on B1 and the remaining one (10%) was positive only based on MAG-1. In general, of the patients, five (50%) were positive using SAG-4 and three (30%) were positive in term of MAG-1 using PBMCs with real-time PCR. CONCLUSION: It appears that PBMC samples have the best performance as the PCR extraction method and are a good source for toxoplasmosis diagnosis. The use of B22 and B23 target genes due to their high sensitivity and specificity along with bradyzoite genes are recommended for toxoplasmosis diagnosis using PBMC samples with real-time PCR.

DNA-based detection of Leishmania and Crithidia species isolated from humans in cutaneous and post-kala-azar dermal leishmaniasis from Shiraz and Kharameh, southern Iran.

BACKGROUND & OBJECTIVES: Leishmania major and L. tropica are the main pathogens of cutaneous leishmaniasis (CL) in several rural and some urban regions of Iran, respectively. The aim of this study was to detect Leishmania species, and update the distribution data of these species in humans suspected to CL in two endemic foci in southern Iran. METHODS: From March 2016 to March 2017, 276 positive samples from of 350 suspected cases were diagnosed and compared by different diagnostic methods, viz. microscopy, culture, and PCR. In PCR assay, four different gene identifications were performed including minicircle kDNA, and cysteine protease B genes for Leishmania detection, and glyceraldehyde-3-phosphate dehydrogenase, and internal transcribed spacer 1 genes for Crithidia detection. RESULTS: In total, 68% (235/350) and 65.3% (177/271) of patients suspected of leishmaniasis were positive by microscopy and cultivation methods. In PCR assay, L. major, and L. tropica were detected in 86.2% (238/276), and 13.1% (36/276) of CL cases, respectively. Also, dermal L. infantum strain was isolated from 0.7% (2/276) of post-kala-azar dermal leishmaniasis patients. In addition, Crithidia fasciculata was detected in two CL patients chronically infected with L. major. INTERPRETATION & CONCLUSION: It appears that the epidemiology of CL has changed during the last decades and can complicate the control strategy aspects of CL in southern Iran. Therefore, more epidemiological, ecological, and gene polymorphism studies are needed to understand the pathogenic role of these species in human, as a main host of leishmaniasis in Iran.

Anti-Toxoplasma In Vitro and In Vivo Activity of Pyrus boissieriana Arbutin-Rich Fraction.

PURPOSE: Pyrus boissieriana is a rich source of arbutin and has been used in herbal medicine to treat infectious diseases. This study aimed to investigate the effect of the arbutin-rich fraction of Pyrus boissieriana aerial parts on Toxoplasma gondii In Vitro and In Vivo. METHODS: An arbutin-rich fraction of P. boissieriana was prepared beforehand. Flow cytometry was used to evaluate the effect of different concentrations (1-512 µg/ml) of the P. boissieriana arbutin-rich fraction on Toxoplasma tachyzoites (RH strain). The cytotoxicity of the concentrations on the macrophage J774 cell line was also investigated by MTT assay. For In Vivo investigation, 4-6-week-old female mice infected with the RH strain of T. gondii were treated with different doses (16, 32, 64, 256, and 512 mg/kg) of the fraction using gavage. RESULTS: The highest and lowest lethality of the tachyzoites were 89.6% and 25.9% related to the concentrations of 512 µg/ml and 1 µg/ml, respectively, with an IC50 value of 18.1 µg/ml ± 0.37. The cytotoxicity test showed an IC50 value of 984.3 µg/ml ± 0.76 after 48 h incubation. The mean survival of mice at the lowest treated dose (16 mg/kg) was 6.6 days, and it was 15 days at the highest dose (512 mg/kg). The concentrations of 512, 256, 128, and 64 mg/kg of the fraction compared to the negative control (6.2 days mean survival) significantly increased the survival time of mice (P < 0.001, P = 0.009, P = 0.018, and P = 0.021, respectively). CONCLUSION: The results showed that the arbutin-rich fraction of P. boissieriana is effective against T. gondii In Vitro and In Vivo and may be a reliable alternative to conventional treatment for toxoplasmosis, although further studies are necessary.

Preparation and characterization of artemether-loaded niosomes in Leishmania major-induced cutaneous leishmaniasis.

Cutaneous leishmaniasis is the most prevalent form of leishmaniasis worldwide. Although various anti-leishmanial regimens have been considered, due to the lack of efficacy or occurrence of adverse reactions, design and development of novel topical delivery systems would be essential. This study aimed to prepare artemether (ART)-loaded niosomes and evaluate their anti-leishmanial effects against Leishmania major. ART-loaded niosomes were prepared through the thin-film hydration technique and characterized in terms of particle size, zeta potential, morphology, differential scanning calorimetry, drug loading, and drug release. Furthermore, anti-leishmanial effect of the preparation was assessed in vitro and in vivo. The prepared ART-loaded niosomes were spherical with an average diameter of about 100 and 300 nm with high encapsulation efficiencies of > 99%. The results of in vitro cytotoxicity revealed that ART-loaded niosomes had significantly higher anti-leishmanial activity, lower general toxicity, and higher selectivity index (SI). Half-maximal inhibitory concentration (IC50) values of ART, ART-loaded niosomes, and liposomal amphotericin B were 39.09, 15.12, and 20 µg/mL, respectively. Also, according to the in vivo study results, ART-loaded niosomes with an average size of 300 nm showed the highest anti-leishmanial effects in animal studies. ART-loaded niosomes would be promising topical drug delivery system for the management of cutaneous leishmaniasis.

Molecular epidemiology and multilocus genotyping of Giardia duodenalis in individuals attending major public hospitals in Shiraz, southwestern Iran: A public health concern.

Giardia duodenalis is one of the most common causes of waterborne disease worldwide, and is often associated with outbreaks of diarrhea in areas with poor sanitation and hygiene. This study aimed to assess the prevalence and genetic diversity of G. duodenalis assemblages in individuals attending major public hospitals in Shiraz, southwestern Iran. From August 2022 to May 2023, a total of 614 stool samples from individuals were collected and initially examined for G. duodenalis cysts using parasitological techniques, sucrose flotation, and microscopy. Microscopy-positive samples were validated by SSU-PCR amplification of the parasite DNA. A multilocus genotyping (MLG) scheme, which focused on the triose phosphate isomerase (tpi) and the glutamate dehydrogenase (gdh) genes, was employed for genotyping purposes. G. duodenalis cysts were found in 7.5% (46/614) and 8.5% (52/614) of samples through microscopy and SSU-PCR, respectively. Successful amplification and sequencing results were obtained for 77.3% (17/22) and 45.5% (10/22) of the infected samples at the tpi and gdh loci, respectively. MLG data for the two loci were available for only five samples. Out of the 22 samples genotyped at any loci, 54.5% (12/22) were identified as assemblage A, while 45.5% (10/22) were identified as assemblage B. AII was the most predominant sub-assemblage identified [54.5% (12/22)], followed by BIII [27% (6/22)], discordant BIII/BIV [13.6% (3/22)], and BIV [4.5% (1/22)]. In the present study, no assemblages suited for non-human animal hosts (e.g., C-F) were detected. This suggests that the transmission of human giardiasis in Shiraz is primarily anthroponotic. Further molecular-based analyses are necessary to confirm and expand upon these findings. These analyses will also help determine the presence and public health importance of the parasite in environmental samples, such as drinking water.

Development of New PCR Protocols to Detect Genetic Diversity in the Metronidazole Metabolism Genes in Susceptible and Refractory Clinical Samples of Giardia duodenalis.

PURPOSE: Investigating the genetic variation in thioredoxin reductase (TrxR) and nitroreductase (NR) genes in both treatment-resistant and -sensitive Giardia duodenalis isolates can provide valuable information in identifying potential markers of resistance to metronidazole. The rapid increase in metronidazole treatment failures suggests the presence of genetic resistance mechanisms. By analyzing these genes, researchers can gain insights into the efficacy of metronidazole against G. duodenalis and potentially develop alternative treatment strategies. In this regard, four G. duodenalis isolates (two clinically sensitive and two clinically resistant to metronidazole) were collected from various hospitals of Shiraz, southwestern Iran. METHODS: Parasitological methods including sucrose flotation and microscopy were employed for the primary confirmation of G. duodenalis cysts in stool samples. Microscopy-positive samples were approved by SSU-PCR amplification of the parasite DNA. All four positive G. duodenalis specimens at SSU-PCR were afterward analyzed utilizing designed primers based on important metronidazole metabolism genes including TrxR, NR1, and NR2. RESULTS: Unlike TrxR gene, the results of NR1 and NR2 genes showed that there are non-synonymous variations between sequences of treatment-sensitive and -resistant samples compared to reference sequences. Furthermore, the outcomes of molecular docking revealed that there is an interaction between the protein sequence and spatial shape of treatment-resistant samples and metronidazole in the position of serine amino acid based on the NR1 gene. CONCLUSION: This issue can be one of the possible factors involved in the resistance of Giardia parasites to metronidazole. To reach more accurate results, a large sample size along with simulation and advanced molecular dynamics investigations are needed.

Calomyscid Rodents (Rodentia: Calomyscidae) as a Potential Reservoir of Zoonotic Cutaneous Leishmaniasis in a Mountainous Residential Area in the Plateau of Iran: Inferring from Molecular Data of kDNA and ITS2 Genes of Leishmania Major.

Cutaneous leishmaniasis (CL), a neglected tropical disease, is an important health problem in Fars Province, southern Iran. Fars, the fourth most populous Province in Iran, is the center of both anthroponotic and zoonotic cutaneous leishmaniasis (ZCL). Rodents, the reservoir of Leishmania major, play an important role in transmitting ZCL. In the present study, we report Leishmania infection in calomyscid rodents for the first time in mountainous residential areas of Shiraz, the capital of Fars Province, in southern Iran. Rodents were trapped in urban mountainous areas. The skin, liver, and spleen of rodents were examined microscopically for Leishmania infection. In addition, DNA was extracted from the tissues and they were evaluated for Leishmania infection by targeting the kDNA and subsequent sequencing of the nuclear rDNA internal transcribed spacer two (ITS2) region. DNA of L. major was detected in the spleen and liver of calomyscid rodents. Molecular evolution based on DNA-sequencing of the ITS2 gene confirmed the taxonomic situation of the parasite as L. major. Our findings suggest the eco-epidemiological importance of calomyscid rodents in the foci of leishmaniasis in the mountainous residential area on the plateau of Iran. These rodents may play a role in the transmission of leishmaniasis in a residential area and could be considered a potential reservoir for CL.

Toxoplasma gondii infection in patients with brain tumors in Southern Iran: a case-control study.

Considerable evidence points to a dominant role of inflammation in tumor pathology. The biological response of the immune system can be triggered by Toxoplasma gondii as a common brain-tropic parasite. The aim of this study was to investigate an association between Toxoplasma infection and brain tumors. This case-control study was performed on sera of brain tumor patients (n = 124) and age- and sex-matched control subjects (n = 124) in Southern Iran. Data related to tumor site and type were collected during sample collection. Anti-Toxoplasma IgG was assessed by enzyme-linked immunosorbent assay (ELISA). Seroprevalence anti-Toxoplasma IgG was significantly higher in brain tumor patients 30.6% (38/124) compared with 12.1% (15/124) of the healthy controls (OR 3.211; 95% CI 1.658 to 6.219; p = 0.001). The highest seroprevalence was detected in patients with ependymoma (100%), followed by glioblastoma (83%), pituitary adenoma (47.3%), astrocytoma (27.2%), schwannoma (23%), and meningioma (22.6%). The parasite infection was correlated to brain tumor's location i.e., the patients with frontal lobe and sella region tumors had higher seropositivity compared with others (P < 0.05). The higher prevalence of Toxoplasma infection among patients with brain tumor compared with the control group indicates a probable association between the infection and brain tumors.

The in vitro and in vivo effects of Lucilia sericata larval secretions on Leishmania major.

The emerging of drug resistant against Leishmania parasites prompts scientists to seek for novel therapeutic strategies against theses infectious protozoan parasites. Among different strategies, the use of larvae secretions could be suggested as a possible therapy with low side effects. Accordingly, the current study evaluated the in vitro and in vivo effects of Lucilia sericata larval secretions on Leishmania major, the causative agent of cutaneous leishmaniasis (CL). After preparation of L. sericata larval stages (L2 and L3) secretions, the potential effects of secretions were evaluated against L. major promastigotes and amastigotes (in vitro) using MTT assay. The cytotoxicity effects of secretions were also checked on uninfected macrophages. In addition, in vivo experiments were also conducted to investigate the effects of larvae's secretions on the CL lesions induced in the BALB/c mice. Although the increased concentration of larvae secretions exhibited a direct effect on the promastigotes proliferation (viability), contrarily, L2 secretions at a concentration of 96 µg/ml represented the highest inhibitory effect on parasite (amastigotes) burden in infected macrophages. Interestingly, L3 secretions > 60 µg/ml induced inhibitory effects on amastigotes. The results relevant to the cytotoxicity effects of L2 and L3 secretions on uninfected-macrophages showed a dose dependent correlation. In vivo results were also significant, compared to the positive control group. This study suggested the plausible inhibitory effects of L. sericata larvae's secretions on the L. major amastigotes and CL lesions progression. It seems that the characterization of all effective components/proteins in the larvae secretions and their specific targets in parasite structure or in cell (macrophage) responses could further reveal more details regarding the anti-leishmanial properties of these compounds.

Synthesis and anti-Toxoplasma activity of indole-triazole compounds on tachyzoites of RH strain.

BACKGROUND: Conventional treatment for toxoplasmosis have severe side effects and the inability to completely eradicate the disease. Therefore, the acquisition of new anti-Toxoplasma drugs has always been of interest among researchers. In the present study, we prepare a new indole-triazole derivatives and evaluated their potential anti-parasitic activity against tachyzoites of Toxoplasma RH strain. MATERIALS AND METHODS: In this study, after synthesis of the two new compounds of indole-triazole, the effect of their different concentrations (2-1024 µg/ml) were determined on Toxoplasma tachyzoites using flow cytometry. Furthermore, tachyzoites were exposed to different concentrations of compounds (4, 16, 64, 265, 1024 µg/ml) for 1.5 h and their infectivity were evaluated in BALB/c mice. RESULTS: The flow cytometry results indicated the benzyl derivative of indole-triazole in various concentrations had a lethal effect on tachyzoites between 11.93% and 89.66%, while the naphthalene derivative had a lethality of 26.63%-66.82%. The infectivity analysis showed that the survival time of mice at concentrations of 1024 µg/ml and 512 µg/ml of benzyl derivatives was significantly increased (P = 0.008 and P = 0.016, respectively), compared to that in the negative control group. Furthermore, survival time of mice was statistically significant at the concentration of 1024 µg/ml for naphthyl derivative (P = 0.012). CONCLUSION: Findings of the current study suggested indole triazole compounds, based on their structure and enzymes targeting, have a considerable effect on tachyzoites of T. gondii RH strain and can be considered as a new anti-Toxoplasma agent.

The Relationship of Latent Toxoplasmosis and Cigarette Smoking: Seroprevalence, Risk Factor, and Case-Control Study in Fars Province, Southern Iran.

Toxoplasmosis is a parasitic disease with worldwide prevalence. Despite the relatively similar effects of toxoplasmosis and smoking on alteration in neurotransmitters, especially dopamine, little is known about the relation of Toxoplasma gondii infection and addiction to cigarette smoking. Therefore, the main objective of this study was to assess the relationship between latent toxoplasmosis and smoking. Through a case-control study, 216 regular cigarette smokers and 324 nonsmoker age- and gender-matched subjects were evaluated for anti-T.gondii IgG antibodies with enzyme-linked immunosorbent assay (ELISA). During the sampling, a structured questionnaire was used to obtain the demographic information of participants and the risk factors of acquired Toxoplasma. The median ages of case and control groups were 51.04 ± 18.1 (22-97 years) and 51.03 ± 16.5 (21-89 years), respectively (p = 0.99). Anti-T.gondii IgG antibodies were detected in 44 (20.37%) cases and in 135 (41.67%) controls. There was a statistically significant difference for the positivity rate between the smokers and the control group (OR = 0.35; 95%CI: 0.19-0.65; and p = 0.001). The overall prevalence was 33.14%. This study indicated the inverse association between seropositivity to Toxoplasma infection and cigarette smoking. This relationship could be due to the changes that latent toxoplasmosis has on the neurotransmitters, especially dopamine, which needs more research.

Molecular Characterization and In Silico Analyses of Maurolipin Structure as a Secretory Phospholipase A 2 (sPLA2) from Venom Glands of Iranian Scorpio maurus (Arachnida: Scorpionida).

The venom is a mixture of various compounds with specific biological activities, such as the phospholipase A 2 (PLA2) enzyme present in scorpion venom. PLA2 plays a key role in inhibiting ryanodine receptor channels and has neurotoxic activity. This study is the first investigation of molecular characterization, cloning, and in silico analyses of PLA2 from Iranian Scorpio maurus, named Maurolipin. After RNA extraction from S. maurus venom glands, cDNA was synthesized and amplified through RT-PCR using specific primers. Amplified Maurolipin was cloned in TA cloning vector, pTG19. For in silico analyses, the characterized gene was analyzed utilizing different software. Maurolipin coding gene with 432 base pair nucleotide length encoded a protein of 144 amino acid residues and 16.34 kilodaltons. Comparing the coding sequence of Maurolipin with other characterized PLA2 from different species of scorpions showed that this protein was a member of the PLA2 superfamily. According to SWISS-MODEL prediction, Maurolipin had 38.83% identity with bee venom PLA2 with 100% confidence and 39% identity with insect phospholipase A 2 family, which Phyre2 predicted. According to the three-dimensional structure prediction, Maurolipin with five disulfide bonds has a very high similarity to the structure of PLA2 that belonged to the group III subfamily. The in silico analyses showed that phospholipase A 2 coding gene and protein structure is different based on scorpion species and geographical condition in which they live.

Acute toxoplasmosis can increase serum dopamine level.

Toxoplasmosis is a globally parasitic zoonotic disease transmitted by Toxoplasma gondii protozoa. This infection in its chronic form can cause a change in its host's specific behavior and is also associated with developing neuropsychological symptoms in humans. Changes in neurotransmitters' levels, especially dopamine, have been identified as a behavior change factor in the infected host. This study aimed to evaluate serum dopamine levels in acute murine toxoplasmosis. In this study, 50 mice infected with Toxoplasma were studied in 5 separate groups, and ten healthy mice were considered as negative control. For five consecutive days after parasite injection, blood sampling and serum isolation were performed daily from one of the groups. Serum dopamine levels were measured by HPLC method. Statistical studies showed that serum dopamine on the first to the fourth day after parasite inoculation was the same as the negative control, but the fifth day began to increase. The present study results indicate that dopamine production in mice infected with Toxoplasma gondii increases from day five after infection. This result suggests that in acute toxoplasmosis, dopamine production is low, and the trend of chronic disease increases dopamine production.

Toxoplasma Reduces Complications of Parkinson's Disease: An Experimental Study in BALB/c Mice.

Background: Parkinson's disease (PD) has been described in dopamine brain level reductions. Conversely, several studies have shown that Toxoplasma parasite can increase the level of dopamine in an infected host. This study was conducted to assess the serum, cerebral dopamine levels, and downregulation of Parkinson's disease manifestations in mice with chronic toxoplasmosis. Methods: PD induction was done by oral inoculation of rotenone into BALB/c mice. To induce the chronic infection, cysts of T. gondii Prugniaud strain (genotype II) were injected intraperitoneally into the mice. The rotarod test was used for the evaluation of functional motor disorders in experimental mice. The serum and cerebral dopamine levels of the mice were also measured by using high-performance liquid chromatography (HPLC) on consecutive periods (10 days). Results: Findings of the rotarod test showed the highest and lowest average of running duration belonged to the uninfected mice and PD mice, respectively. Remarkably, the running duration of infected mice with PD was higher than PD mice. As well, the level of serum and cerebral dopamine increased in mice with PD and toxoplasmosis in comparison with PD mice. Conclusion: Increasing the serum and cerebral dopamine levels in mice infected with toxoplasmosis is related to the presence of the parasite. Moreover, the dopamine upregulation due to the infection is effective in the reduction of PD complications.

Occurrence, genetic characterization, and zoonotic importance of Giardia duodenalis in various species of rodents (Mus musculus, Rattus norvegicus, and Rattus rattus).

Giardia duodenalis is a well-known flagellated parasite and the causative agent of protozoal diarrhea in animals and humans worldwide. Current study was aimed at determination of G. duodenalis prevalence, genetic variation and zoonotic significance in various species of rodents in Shiraz, southwestern Iran. In brief, 120 fecal specimens were collected from rodents (Rattus rattus, Rattus norvegicus, and Mus musculus) during May up to November 2021 and microscopically examined for Giardia cysts. Further molecular characterization of positive samples was done by nested-PCR, followed by nucleotide sequencing of the triose phosphate isomerase (tpi) gene. A total prevalence of 3.3% (4/120) was observed in rodents, with highest rate in black rats [5% (2/40)]. Regarding brown rats and house mice, only one sample was found to be positive, showing 2.5% and 2.5% prevalence, respectively. It is noteworthy that Giardia B and G assemblages were found in black rats (one case/genotype), whereas the only positive samples from brown rats and house mice were characterized as assemblage G. The major findings of the present study were the presence of both zoonotic and non-zoonotic Giardia assemblages in examined rats in Shiraz and the potential of black rats to harbor Giardia infection to humans. These concerns should be taken seriously in terms of public health. Nevertheless, the true epidemiology and assemblage distribution of Giardia is still open to question.

The relationship between Toxoplasma gondii infection in mothers and neonate's gender.

BACKGROUND: The secondary sex ratio can be affected by various factors such as stress, immunosuppression, and age of parents in addition to mother infectious disease (Maternal infections). Toxoplasmosis is one of the critical maternal parasitic infections during pregnancy. Besides the complications of the acute form of the disease, hormonal shifts, and even alterations in the secondary sex ratio can be induced by the manipulative activity of the chronic form of the disease. Therefore, this study aimed to evaluate the correlation between Toxoplasma gondii infection in mothers and neonate's gender. METHODS: In this case-control study, 137 seropositive mothers to Anti-Toxoplasma IgG(case) was compared to 137 age-matched subject Toxoplasma-seronegative mothers(control) in terms of their neonate's gender. These individuals were randomly selected based on exclusions and inclusions criteria of the study from among 2014 mothers who had been tested for Toxoplasma infection during pregnancy from 2015 to 2018 in Shiraz, Iran. RESULTS: From a total of 2014 studied pregnant mothers, 326 (16.2%) mothers were seropositive to anti-Toxoplasma IgG, and 1688 (83.8%) were negative for IgG. It was found that the numbers of female and male neonates were 136 (45.48%) and 163 (54.51%) in the control group whereas, they were 165 (49.84%) and 166 (50.15%) in the case group, respectively. The sex ratio was 1.006:1 in Toxoplasma-seropositive and 1.2:1 in Toxoplasma-seronegative mothers. The number of male and females offsprings indicated a significant difference in Toxoplasma-seronegative mothers (54.5%, p = .015). Moreover, comparing the number of males and females between the two randomly selected groups showed that female gender is significantly more than male gender in seropositive mothers to Toxoplasma (54.8%, p = .014), which means that of 301 females, 165 offspring were born to seropositive mothers. No significant difference was observed for the sex ratio of aborted fetuses between groups. However, in the Toxoplasma-seropositive group, the sex ratio of aborted fetuses showed that the aborted male fetuses were significantly higher in number. (31 male vs 13 female, p < .001). CONCLUSION: Comprehensively, a significant relationship was found between chronic Toxoplasma infection and secondary sex ratio. However, it is suggested that this relationship be investigated in further studies as well as an animal study.