Assuntos
Ascaríase/fisiopatologia , Ascaris lumbricoides , Ingestão de Alimentos , Ingestão de Energia , Entamebíase/fisiopatologia , Enteropatias Parasitárias/fisiopatologia , Animais , Ascaríase/epidemiologia , Ascaríase/parasitologia , Criança , Estudos Transversais , Entamebíase/epidemiologia , Entamebíase/parasitologia , Feminino , Humanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Masculino , México/epidemiologia , Prevalência , População Rural , Especificidade da EspécieRESUMO
BACKGROUND: Intestinal parasites, virus and bacterial infections are positively associated with obesity and adiposity in vitro and in animal models, but conclusive evidence of this relationship in humans is lacking. The aim of this cross-sectional study was to determine differences in adiposity between infected and non-infected children, with a high prevalence of intestinal parasitic infection and obesity. SUBJECTS: A total of 296 school-aged children (8.0 ± 1.5 years) from a rural area in Querétaro, Mexico, participated in this study. Anthropometry (weight, height and waist circumference) and body fat (DXA) were measured in all children. A fresh stool sample was collected from each child and analysed for parasites. Questionnaires related to socioeconomic status and clinical history were completed by caretakers. RESULTS: Approximately 11% of the children were obese, and 19% were overweight. The overall prevalence of infection was 61%. Ascaris lumbricoides was the most prevalent soil transmitted helminth (16%) followed by hookworm. Entamoeba coli was the predominant protozoa (20%) followed by Endolimax nana, Balantidium coli, Entamoeba histolytica/dispar, Iodamoeba bütschlii and Giardia lamblia. Children with moderate-heavy infection of E. coli had significantly higher waist circumference, waist-to-height ratio, body and abdominal fat than children not infected or with light-intensity infection (p < 0.05). CONCLUSION: These findings raise the possibility that a moderate or heavy infection with E. coli may contribute to fat deposition and thereby have long-term consequences on human health. Further studies are needed to better understand if E. coli contributes directly to fat deposition and possible mechanisms.
Assuntos
Adiposidade , Entamoeba/isolamento & purificação , Entamebíase/fisiopatologia , Enteropatias Parasitárias/fisiopatologia , Obesidade Infantil/fisiopatologia , Gordura Abdominal , Adiposidade/fisiologia , Antropometria , Criança , Estudos Transversais , Entamebíase/parasitologia , Fezes/parasitologia , Feminino , Humanos , Enteropatias Parasitárias/parasitologia , Masculino , México , Obesidade Infantil/parasitologia , Prevalência , Classe SocialRESUMO
In vitro exposure of Entamoeba histolytica trophozoites to the sex steroids 17beta-estradiol, progesterone, and dehydrotestosterone had little effect on parasite viability or proliferation. However, treatment with the adrenal steroid dehydroepiandrosterone (DHEA) markedly inhibited parasite proliferation, adherence and motility, and at a certain dose it induced trophozoite lysis. The opposite effect on proliferation was found when the trophozoites were exposed to cortisol. Moreover, DHEA decreased while cortisol increased the parasite's DNA synthesis determined by 3H-thymidine incorporation. Trophozoite lysis by DHEA appeared to be caused by a necrotic rather than an apoptotic process, as observed in propidium iodide and terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling assays. A possible mechanisms of action was derived from experiments demonstrating that the activity of a putative 3-hydroxy-3-methyl glutaryl CoA reductase detected in trophozoite extracts was inhibited in the presence of DHEA. Contrary to its in vitro inhibitory effect, in vivo administration of DHEA to infected hamsters resulted in exacerbation of the amebic liver abscesses. These results demonstrated that androgen steroids act directly upon E. histolytica growth and viability, and may shed new light on some age and gender differences in disease progression, as well as finding application in the drug treatment of human amebiasis.
Assuntos
Desidroepiandrosterona/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/crescimento & desenvolvimento , Hormônios Esteroides Gonadais/farmacologia , Hidrocortisona/farmacologia , Animais , Cricetinae , Entamoeba histolytica/patogenicidade , Entamebíase/parasitologia , Entamebíase/fisiopatologia , Masculino , MesocricetusRESUMO
EhCPADH is an immunogenic, heterodimeric protein that is formed by EhCP112 (cysteine protease) and EhADH112 (adhesin), polypeptides involved in Entamoeba histolytica's cytopathic effect, target-cell adherence and phagocytosis. The EhCPADH complex is located in the plasma membrane and cytoplasmic vacuoles. Here, the independent expression of EhCP112 and EhADH112 in fibroblasts and hamsters was analysed. Also investigated was the immunological response in animals independently inoculated with plasmid pcDNA-Ehcp112, which carries the complete cysteine protease-encoding gene, or with plasmid pcDNA-Ehadh112, which carries the C terminus of the adhesin-encoding gene, or with a mixture of both. Both proteins were expressed in the plasma membranes of the transfected fibroblasts. EhCP112 was toxic for the mammalian cells. Proteins were also independently expressed in hamsters after inoculation with the plasmids. Their expression was indirectly evaluated by the presence of antibodies in the inoculated animals. Remarkably, co-immunization of the animals with the two DNA plasmids resulted in an earlier and higher anti-E. histolytica IgG induction than immunization with separate plasmids. In contrast, the cellular immune response was not noticeably improved by the plasmid mixture. Interestingly, protection against liver abscesses was detected only in animals that received the plasmid mixture and no protection was observed in hamsters independently inoculated with plasmid pcDNA-Ehcp112 or pcDNA-Ehadh112.