In vitro effects of fermented papaya (Carica papaya, L.) on platelets obtained from patients with type 2 diabetes.

BACKGROUND AND AIM: Oxidative stress is associated with insulin resistance pathogenesis, insulin secretion deficiency, and complication onset. Fermented papaya preparation (FPP), a dietary supplement obtained by fermentation of the papaya fruit, may be used as an antioxidant in the prevention of diabetic complications. METHODS AND RESULTS: Platelets from 30 patients with type 2 diabetes mellitus (DM 2) and 15 healthy subjects were analyzed to evaluate the in vitro effects of FPP incubation. Na(+)/K(+)-adenosine triphosphatase (ATPase) activity, membrane fluidity, total antioxidant capacity (TAC), superoxide dismutase (SOD) activity, and conjugated diene levels were determined. In vitro FPP incubation improved platelet function, by enhancing Na(+)/K(+)-ATPase activity and membrane fluidity, and ameliorated the antioxidant system functionality, through an increase in TAC and SOD activity and a parallel decrease in conjugated diene levels in patients with DM 2. CONCLUSION: Our data suggest that the incubation with FPP may have a protective effect on platelets from patients with DM 2, by preventing the progression of oxidative damage associated with diabetes and its complications.

[Pharmacology of atriopeptin in the adult rat: power spectra of the fluctuations in heart rate]. / Farmacologia dell'atriopeptina nel ratto adulto: spettri di potenza delle fluttuazioni della frequenza cardiaca.

The persistence of the cardiac beat-to-beat control is studied in the anesthetized and the pithed adult rat by means of spectral analysis. The data show that atriopeptin affects the amplitude of the heart rate low frequency fluctuations, significantly increasing the spectral patterns both in the anesthetized and the pithed rat. The atriopeptin enhancement of the low frequency range in heart rate fluctuations provides further insight into the hypothesis that beat to beat variability in hemodynamic parameters reflects a compensatory response in the short term cardiovascular control.

[Persistence of the control of the fluctuations of heart rate in the anesthetized and pithed adult rat. Effect of enteraminergic drugs]. / Persistenza del controllo delle fluttuazioni della frequenza cardiaca nel ratto adulto, anestetizzato e "periferico". Effetti di trattamenti farmacologici enteraminergici.

Spontaneous fluctuations in heart rate were analyzed by spectral analysis in the ether anesthetized and pithed adult rat. In order to investigate the changes in the spectral pattern of the fluctuations, the selective 5HT-2 and -3 isoreceptor blockers ritanserin and BRL 43694A were used. In both the experimental conditions, ritanserin blockade led to dose-dependent increased fluctuations in HR low and high frequencies. In both the anesthetized and pithed rats, the low frequency range HR fluctuations were drastically reduced by BRL 43694A.