Comparative Efficacy of Diethylcarbamazine, Nitazoxanide and Nanocomposite of Nitazoxanide and Silver Nanoparticles on the Dehydrogenases of TCA Cycle in Setaria cervi, in Vitro

Background: Bovine filariid, Setaria cervi may cause serious pathological condition such as cerebrospinal nematodiasis in sheep, goat and horses. Since TCA cycle enzymes have certain biological functions that make them essential for the survival of parasite and therefore, efficacy of diethylcarbamazine (DEC), nitazoxanide (NTZ) and a nanocomposite of nitazoxanide and silver nanoparticles (NTZ+AgNPs) was assessed on succinate, malate and isocitrate dehydrogenases in the microfilariae (mf) and adult S. cervi worms. Methods: This study was conducted in the Department of Zoology, Aligarh Muslim University, Aligarh, India during 2015-2016. Adult and microfilariae of S. cervi were incubated in 100 mg/ml of DEC, NTZ, and NTZ+AgNPs for 24 and 6 h, respectively at 37 °C. Succinate, malate and isocitrate dehydrogenases were localized by putting the mf and adult worms in the incubating medium containing their respective substrates at 37 °C for 2 h followed by counterstaining in 2% methylene green for 15 min. Results: Maximum inhibition of TCA cycle enzymes was observed in both microfilariae and adult worms treated with nanocomposite of NTZ-AgNPs. Ruptured sheath along with nanoparticles sticking to the body surface was noticed in NTZ+AgNPs treated microfilariae. Conclusion: NTZ+AgNPs proved most effective synergistic combination against TCA cycle enzymes which blocked the isocitrate and malate dehydrogenase almost completely, and succinate dehydrogenase to large extent in both microfilariae as well as adult worms of S. cervi. AgNPs ruptured the sheath and allowed the NTZ to attach and penetrate the main body to exert maximum effect on the enzymes

Immunopathological response of leukocytes against microfilariae and adult worms in white rats infected with Setaria cervi

Aim: Aim of this study was to see the immunopathological changes against the microfilariae (Mf) and adult worms of a bovine filarid, Setaria cervi in the tissues of vital organs of experimentally infected white rats. The effect of diethylcarbamazine (DEC) was also observed on the Mf, as leukocytes especially lymphocytes produce immunoglobulins which opsonize and increase the efficacy of DEC against circulating Mf. Effect of this drug was also assessed on liver enzymes in the microfilaremic rats. Materials and Methods: Microfilaremia was established by implanting adult worms intraperitoneally and by the infusion of Mf recovered from the uterus of gravid female worms. DEC was administered orally for six consecutive days in the rats having patent infection. Differential leukocyte count was recorded every 3rd day, and liver enzymes were estimated every 10th day in both treated and untreated rats. Pathological changes were observed in HE stained sections of vital organs where Mf or adult worms were trapped. Results: Destruction and reduction in microfilarial density were noticed in microfilaremic rats treated with DEC. Trapped Mf and embedded worms revealed heavy cellular infiltrations by defensive cells which surrounded and attached with the body surface of the Mf as well as adult worms for their destruction and piece meal clearance. Immune-mediated pathology was observed in the tissue sections of lungs, spleen, and liver. Liver enzymes were elevated during the period of higher parasitemia. Conclusion: There was a moderate level of immunopathology against the Mf and adult worms by the leukocytes in experimentally infected microfilaremic rats. Mf were in the process of degeneration where they got trapped. Moderate increase in liver enzyme was noticed which was slightly more in untreated group. Although a fraction of Mf gets killed in the peritoneum, majority of them successfully enter the systemic circulation and survive for about 54 days, which is sufficient enough for conducting immunological and chemotherapeutic studies

Epidemiology, Pathology and Treatment of Cutaneous Leishmaniasis in Taif Region of Saudi Arabia

Background: Cutaneous leishmaniasis is an annoying and disfiguring disease affecting around 1,500,000 individuals globally. There are endemic pockets of this disease in Taif region. In some patients, lesion often weeps and leads to scar formation. The study was conducted to see the efficacy of fluconazole and itraconazole in the patients of cutaneous leishmaniasis and the effect of these drugs on liver enzymes and kidney markers. Methods: Positivity of Leishmania was recorded by microscopic examinations of smears. Specific diagnosis for Leishmania major and L. tropica was made with the help of nested polymerase chain reaction. Fluconazole was given at the rate of 200mg/day while itraconazole was given at 150mg/day for six weeks. AST, ALT, creatinine and urea were estimated during medication. Results: Leishmania major and L. tropica were the species responsible for cutaneous leishmaniasis in Taif region. 81% patients had single lesions, mostly on face followed by hands and legs. 15% of the lesions had bacterial contamination.In terms of efficacy, fluconazole gave slightly better results compared to itraconazole. After 6 weeks of medications, slightly elevated values were recorded for liver enzymes and creatinine. Conclusion: Transmission of leishmaniasis in Taif region is probably because of poor coverage of residual insecticides spraying at hiding places in pile-ups of rocks and abandoned houses from where sand flies visit nearby houses and cattle sheds during night. Fluconazole and itraconazole may be used for the treatment of cutaneous leishmaniasis with good recovery rate and fewer side effects

Effects of filaricidal drugs on longevity and enzyme activities of the microfilariae of Setaria cervi in white rats

Objective: To analyse the efficacy of diethylcarbamazine (DEC), tetramisole and chlorpromazine on the longevity and activity of glucose-6-phosphatase and succinate dehydrogenase in the microfilariae recovered from the peripheral circulation of the rats before and after the treatment. Methods: Setaria cervi worms were implanted in white rats via laparotomy and microfilaraemic rats were divided into 4 groups. Groups 1, 2 and 3 were treated with DEC, tetramisole and chlorpromazine respectively, while Group 4 served as infected control. Longevity of microfilariae and differential leucocyte counts were recorded till the disappearance of microfilariae from peripheral blood. Glucose-6-phosphatase and succinate dehydrogenase enzymes were localized in the microfilariae recovered from normal and treated rats. Results: The microfilariae survived for 48 days in untreated rats while survival was reduced to 15, 21 and 27 days after treatment with DEC, tetramisole and chlorpromazine, respectively. Eosinophils and neutrophils increased during 2nd and 3rd weeks, whereas the lymphocytes increased during 4–7 weeks. DEC treatment resulted in slight decrease in the localization of succinate dehydrogenase but not in glucose-6-phosphatase. Tetramisole and chlorpromazine treatment did not show any appreciable change in the localization of both the above enzymes. Conclusions: DEC proved the most effective drug which cleared the microfilaraemia within 15 days and reduced the activity of succinate dehydrogenase to some extent followed by tetramisole and chlorpromazine which took more time for the clearance of microfilariae and had no effect on the localization of both glucose-6-phosphatase and succinate dehydrogenase

Multiple origins of Plasmodium falciparum dihydropteroate synthetase mutant alleles associated with sulfadoxine resistance in India

With the spread of Chloroquine (CQ) resistant malaria in India, Sulfdoxine - Pyrimethamine (SP) alone or in combination with Artesunate is used as an alternative antimalarial drug. Due to continuous drug pressure, the Plasmodium falciparum parasite is exhibiting resistance to antifolates because of mutations in candidate genes dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps). Our earlier study on flanking microsatellite markers of dhfr mutant alleles from India had shown single origin of the pyrimethamine resistance, with some minor haplotypes, which shared haplotypes with South East Asian (Thailand) strains. In the present study, we have analyzed 193 of these Indian P.falciparum isolates for 15 microsatellite loci around dhps to investigate the genetic lineages of the mutant dhps alleles in different part of the country. Eighty one of these samples had mutant dhps alleles, of which 62 were from Andaman and Nicobar Islands and remaining 19 from mainland India. Of 112 wild type dhps allele, 109 were from mainland India and only 3 from Andaman and Nicobar Islands. Consistent with the model of selection, the mean expected heterozygosity (H<SUB>e</SUB>) around mutant dhps alleles (H<SUB>e</SUB>= 0.55; n=81) associated with sulfadoxine resistance was lower (P≤ 0.05) compared to the mean H<SUB>e</SUB> around wild type dhps allele (H<SUB>e</SUB>=0.80; n=112). There was more genetic diversity in flanking microsatellites of dhps than dhfr among these isolates which confirms the assertion that dhps mutations are at a very early stage of fixation in parasite population. Microsatellite haplotypes around various mutant dhps alleles suggests that the resistant dhps alleles have multiple independent origins in India, especially in Andaman and Nicobar Islands. Determining the genetic lineages of the resistant dhps alleles on the Andaman and Nicobar Islands and mainland India is significant given the role of Asia in the intercontinental spread of chloroquine and pyrimethamine resistant parasite in the past