A Positive Association between T. gondii Seropositivity and Obesity

Abstract

Obesity is a global public health problem that is linked with morbidity, mortality, and functional limitations and has limited options for sustained interventions. Novel targets for prevention and intervention require further research into the pathogenesis of obesity. Consistently, elevated markers of inflammation have been reported in association with obesity, but their causes and consequences are not well understood. An emerging field of research has investigated the association of infections and environmental pathogens with obesity, potential causes of low grade inflammation that may mediate obesity risk. In this study, we estimate the possible association between Toxoplasma gondii (T. gondii) infection and obesity in a sample of 999 psychiatrically healthy adults. Individuals with psychiatric conditions, including personality disorders, were excluded because of the association between positive serology to T. gondii and various forms of serious mental illness that have a strong association with obesity. In our sample, individuals with positive T. gondii serology had twice the odds of being obese compared to seronegative individuals (p = 0.01). Further, individuals who were obese had significant higher T. gondii IgG titers compared to individuals who were non-obese. Latent T. gondii infection is very common worldwide, so potential public health interventions related to this parasite can have a high impact on associated health concerns.

Immune response in the adipose tissue of lean mice infected with the protozoan parasiteNeospora caninum

“…59 Therefore the elevated serum leptin observed in the infected mice may contribute to the lower frequencies of Treg and increased Th1 cells observed in the adipose tissue independently of the presence of parasites. Interestingly, a positive association between seropositivity for T. gondii and obesity has recently been reported 60 and plasma leptin levels were also increased in the serum of T. gondii-infected rats. 61 Our results add evidence in that apicomplexa parasites are able to affect metabolic parameters.…”

Influence of Toxoplasma gondii infection on symptoms and signs of premenstrual syndrome: A cross-sectional study

“…In humans, T. gondii infection has been associated with weight gain in pregnant women [42]. In addition, both T. gondii seroprevalence and high IgG anti- T. gondii antibody levels have been associated with obesity [43]. In fact, results of the positivity to both IgG antibodies against T. gondii and DNA of T. gondii in this study showed that women with obesity had a significantly higher prevalence of T. gondii than women without obesity.…”

Possible Pivotal Role of Latent Chronic T. gondii Infection in the Pathogenesis of Atherosclerosis

“…Individuals who were obese had a markedly higher T. gondii IgG titers compared to normal weight participants [652] . Also Baltaci and Mogulkoc [653] found that rats infected with T. gondii had significantly increased plasma leptin levels four weeks after the intraperitoneal injection of live parasites as compared with control animals ( Table 24).…”

“…It was demonstrated that increased leptin levels correlated with enhanced concentrations of inflammatory markers in morbidly obese individuals [645] , and recently, Reeves et al [652] reported a significant positive association between T gondii seropositivity and obesity (p = 0.01). Individuals who were obese had a markedly higher T. gondii IgG titers compared to normal weight participants [652] .…”