Parasitology

Research Article

Chronic indeterminate phase of Chagas’ disease: mitochondrial involvement in infection with two strains

ALEJANDRA LIDIA BÁEZa1 c1, MARÍA SILVINA LO PRESTIa1, RICARDO FRETESa2, CINTIA DÍAZa2, PATRICIA PONSa3, PAOLA CAROLINA BAZÁNa1, MARIANA STRAUSSa1, HÉCTOR WALTER RIVAROLAa1 and PATRICIA PAGLINI-OLIVAa1

a1 Cátedra de Física Biomédica, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba. Santa Rosa 1085. PC 5000. Córdoba, Argentina

a2 Cátedra de Biología Celular, Histología y Embriología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba. 5016 Córdoba, Argentina

a3 Centro de Microscopia, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba. 5016 Córdoba, Argentina

SUMMARY

Chagasic cardiopathy has become one of the most frequent causes of heart failure and sudden death, as well as one of the most common causes of cardio-embolic stroke in Latin America. The myocyte response to oxidative stress involves the progression of cellular changes, primarily targeting the mitochondria and modifying therefore the energy supply. In this paper we analysed the effect of the infection of mice with 2 different strains of Trypanosoma cruzi (Tulahuen and SGO Z12) in the chronic indeterminate stage (75 days post-infection), upon the structure and function of cardiac mitochondria. The structural results showed that 83% of the mitochondria from the Tulahuen-infected mice presented an increase in their matrix and 91% of the mitochondria from the SGO Z12-infected group showed a reduction in their diameter (P < 0·05). When the Krebs cycle and mitochondrial respiratory chain functionality was analysed through the measurement of the citrate synthase and complexes I to IV activity, it showed that their activity was altered in all cases in a similar manner in both infected groups. In this paper we have demonstrated that the chronic indeterminate phase is not ‘silent’ and that cardiac mitochondria are clearly involved in the genesis and progression to the chronic chagasic cardiopathy when different factors alter the host-parasite equilibrium.

(Received June 18 2012)

(Revised September 05 2012)

(Revised September 20 2012)

(Accepted September 20 2012)

(Online publication November 09 2012)

Key words

  • Chronic indeterminate Chagas' disease;
  • Trypanosoma cruzi strains;
  • mitochondria;
  • respiratory chain;
  • myocardiopathy

Correspondence:

c1 Corresponding author: Cátedra de Física Biomédica,Facultad de Ciencias Médicas. Universidad Nacional de Córdoba, Santa Rosa 1085. C.P. 5000, Argentina. Tel: + 51 9 351 4332020. E-mail address: alejandralidiab@hotmail.com.

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