Heart rate variability in chronic Chagas patients before and after treatment with benznidazole

Ideal benznidazole dose regimen in chronic chagasic patients: a systematic review

The present study aimed to review the existing literature and to evaluate the best dose regimen for benznidazole in adult patients with Chagas disease in the chronic phase. A systematic review was conducted followed by meta-analysis. Searches were performed in four databases, to include studies published until May 2019. The descriptors used were: "Chagas disease", "benznidazole", "Drug Therapy", "Pharmacokinetics", "Dose-response relationship, drug" and "Chronic disease". The meta-analysis compared studies using the standard dose of 5 mg/kg/day for 30 or 60 days. A total of 608 articles were found, 23 of which were considered eligible for this review and nine were included in the meta-analysis. The studies selected and analyzed were published between 1996 and 2018, with various benznidazole dose regimens, ranging from 2.5 mg/kg/day to 10 mg/kg/day, for 30 to 80 days of treatment. The results pointed to a great diversity of dose regimens, thus there is no consensus on the optimal dose regimen for benznidazole in the chronic phase of Chagas disease.

Poly-epsilon-caprolactone nanoparticles enhance ursolic acid in vivo efficacy against Trypanosoma cruzi infection

Despite affecting millions of people worldwide, Chagas disease is still neglected by the academia and industry and the therapeutic option available, benznidazole, presents limited efficacy and side effects. Within this context, ursolic acid may serve as an option for treatment, however has low bioavailability, which can be enhanced through the encapsulation in polymeric nanoparticles. Therefore, herein we developed ursolic acid-loaded nanoparticles with poly-ε-caprolactone by the nanoprecipitation method and characterized them for particle size, zeta potential, polydispersity, encapsulation efficiency, morphology by scanning electron microscopy and thermal behavior by differential scanning calorimetry. Results indicated that an appropriate ratio of organic phase/aqueous phase and polymer/drug is necessary to produce smaller particles, with low polydispersity, negative zeta potential and high drug encapsulation efficiency. In vitro studies indicated the safety of the formulation against fibroblast culture and its efficacy in killing T. cruzi. Very importantly, the in vivo study revealed that the ursolic acid-loaded nanoparticle is as potent as the benznidazole group to control parasitemia, which could be attributed to improved bioavailability of the encapsulated drug. Finally, the toxicity evaluation showed that while benznidazole group caused liver toxicity, the nanoparticles were safe, indicating that this formulation is promising for future evaluation.

Cardiac autonomic modulation in non-frail, pre-frail and frail elderly women: a pilot study

Frailty has been defined as a geriatric syndrome that results in high vulnerability to health adverse outcomes. This increased vulnerability state results from dysregulation of multiple physiological systems and its complex interactions. Thus, assessment of physiological systems integrity and of its dynamic interactions seems to be useful in the context of frailty management. Heart rate variability (HRV) analysis provides information about autonomic nervous system (ANS) function, which is responsible to control several physiologic functions. This study investigated the cardiac autonomic modulation by HRV analysis in community-dwelling elderly women classified as non-frail, pre-frail and frail. Twenty-three elderly women were assigned to the following groups: non-frail (n = 8), pre-frail (n = 8) and frail (n = 7). HRV assessment was performed through linear and non-linear analysis of cardiac interval variability. It was observed a higher sympathetic and lower parasympathetic modulation in frail when compared with non-frail and pre-frail groups (p < 0.05) as indicated by frequency domain indices. Additionally, frail group had a decreased 2LV % pattern (that reflects parasympathetic modulation) in the symbolic analysis in comparison with non-frail group. These findings suggest that frail elderly women present an autonomic imbalance characterized by a shift towards sympathetic predominance. Thus, monitoring ANS function in the context of frailty management may be an important strategy to prevention, diagnosis and treatment of this syndrome and its consequences.

The relationship between heart rate variability and serum cytokines in chronic chagasic patients with persistent parasitemia

BACKGROUND

Persistent parasitemia, immunological, and autonomic nervous system impairments may play an important role in the evolution and clinical outcome of the chronic phase of Chagas' disease by triggering functional cardiovascular changes.

METHODS

Three groups were evaluated: 17 chronic chagasic patients with the indeterminate form (IChD), 12 chronic chagasic patients with cardiac forms (ChHD), and 29 individuals as a healthy control group. Parasitemia was assessed by polymerase chain reaction; hemoculture, heart rate variability by linear and nonlinear methods, and interleukin (IL)-1β, IL-4, IL-6, IL-10, IL-12, IL-13, IL-17, and tumor necrosis factor-α, and interferon (IFN)-γ serum cytokines were assessed by enzyme-linked immune assay.

RESULTS

Twenty-nine chronic chagasic patients were positive for parasitemia (17 IChD and 12 ChHD). Heart rate variability parameters in baseline condition and after cold face test were significantly decreased in chagasic patients compared to controls. Tilt tests showed no alteration. However, using nonlinear indices, ChHD patients presented lower values compared to IChD and controls. Differences in the expression of serum cytokines were observed between chagasic patients and controls. However, among the groups, ChHD presented higher median values of IL-10 and lower of IFN-γ compared to IChD.

CONCLUSION

Both chagasic groups present an autonomic impairment using linear methods. The nonlinear methods revealed that the ChHD group had a higher cardiovascular risk. Serum cytokine concentrations between chagasic patients were similar. However, ChHD showed higher concentrations of IL-10 and lower of IFN-γ, suggesting some established process of immune regulation.