Toxoplasma gondii Reactivation Aggravating Cardiac Function Impairment in Mice

Area of Science:

• Infectious Diseases
• Cardiology
• Immunology

Background:

• Toxoplasma gondii reactivation is frequent in immunocompromised individuals, often overshadowing cardiac involvement.
• Cardiac dysfunction in toxoplasmosis is typically masked by neurological symptoms.

Purpose of the Study:

• To investigate cardiac function changes at different stages post-Toxoplasma gondii infection.
• To determine if Toxoplasma gondii reactivation causes more severe cardiac damage.

Main Methods:

• Three mouse models of T. gondii infection were used: acute, chronic latent, and reactivation.
• Cardiac function was assessed using histology, echocardiography, enzyme profiles, and inflammatory/antioxidant factor analysis.
• Macrophage expression was evaluated via immunofluorescence.

Main Results:

• Cardiac damage was observed in acute and reactivation groups, with decreased heart rate and compensatory systolic function.
• Chronic infection led to myocardial fibrosis, impaired diastolic function, and persistent inflammation.
• Reactivation worsened cardiac damage, potentially causing diastolic heart failure, increased macrophage activation, and fibrosis.

Conclusions:

• Reactivation of T. gondii infection aggravates cardiac injury.
• The damage may involve host-cell-mediated immune responses and macrophage-derived cytokines.
• This offers new insights into the pathogenesis of toxoplasmosis-related cardiac complications.