Changes in Mass Measurement Indices, Cardiointervalogram Parameters and Duration of Swimming in Animals with Experimental Type 2 Diabetes Mellitus Treated with Drugs Exerting Antioxidant Properties
Introduction: Diabetic cardiomyopathy is common in patients with labile type I diabetes, with a tendency to ketoacidosis, reduced body weight, and affection of small blood vessels. This research aimed to determine the nature of the reaction of the autonomic nervous system and changes of biometrical indices in experimental diabetes type 1 and under the influence of different forms of quercetin. Material and Methods: White outbred mature male rats were used in the experiments. For diabetes type 1 modeling, a single intraperitoneal streptozotocin injection (50 mg/kg) was used. In 14 days after the injection, animals were divided into three groups: animals with diabetes without treatment; rats that were injected with a water-soluble form of quercetin; rats that were injected with the liposomal form of the bioflavonoid. Bodyweight, heart weight, heart mass ratio, tolerance of animals to physical activity (swimming test), and glucose level in the blood were defined. The state of the autonomic nervous system was estimated according to the indices of cardiointervalography. Results: Quercetin preparations at experimental diabetes type I contributed to the improvement of the mass measurement parameters and functional state of the autonomic regulation of heart activity, causing normalization of the majority of its indices and, as a result, increased the tolerance of animals to physical activity (duration of swimming). Under the influence of the preparations, vagal influence on the heart has been progressively reduced, and the restoration of balance between the tonus of sympathetic and parasympathetic divisions of the autonomic nervous system and centralization of control of heart rhythm were observed. It is important to mention that for most biometrical indices and indices of heart rhythm variability, the activity of the liposomal form of quercetin was more pronounced than its water-soluble form. It is possible that this effect was due to liposomes. Conclusion: The liposomal form of quercetin exhibited higher activity against most biometric and heartbeat rate indicators.