The remodeling of lungs under the influence of alloxan-induced hyperglycemia

Abstract

Introduction: Diabetes mellitus is a global medical and social problem. 2-3% of the population suffers from diabetes mellitus. According to current forecasts, the number of people with diabetes mellitus will double every 15 years. Diabetes mellitus is the basis for the development of complex comorbidities and complications such as diabetic microangiopathy and neuropathy. Diabetes patients are at increased risk for atherosclerosis, coronary heart disease, and renal failure. Scientists around the world have been thoroughly engaged in the problem of hyperglycemia, which is the consequence of type 1 diabetes mellitus, but the causes of its occurrence have not been fully established yet. The study aimed to investigate the lungs of pre-reproductive age rats under the influence of alloxan-induced hyperglycemia. Material and Methods: 12 rats of 3 months of age were involved in the experiment. They were divided into two series: experimental and control. The Control series includes six intact rats. For the experimental modeling of hyperglycemia, we used alloxan monohydrate, pre-dissolved in 0.9% solution of sodium chloride, which was then injected intraperitoneally once at a dose of 20 mg/100 g on an empty stomach. The experiment lasted 60 days. We measured the glucose level using the Accu-Chek Advantage (Boehringer, Germany) at2, 12, and 24 hours after alloxan injection, and then weekly. The average level of glucose in the blood remained at 11 mmol/L ± 2 mmol/L. To study the remodeling of the lungs, we used the histological examination by a light microscope (Olympus BH-2) and histomorphometry using the universal certified program “SEO Scan Lab 2.0” and “SEO Image Lab 2.0”. The obtained data were processed on a personal computer using the software “GraphPad” and a licensed Excel XP spreadsheet editor (Microsoft Office 2013). The data were analyzed by unpaired t-test. P values ≤0.05 were considered as statistically significant. Results: Obtained morphometric data shows the increase of the width of alveoli by 8.5% (p < 0.05), the width of the conducting part of the respiratory bronchiole by 15.7 % (p < 0.05) and the thickness of the interalveolar septum by 8.3% (p < 0.05). The wall thickness of pulmonary vessels increased by 22.9% (p <0.05). Lymphoid nodules were more hypertrophied compared to the control ones by 2.4 times (p <0.05). Conclusions: Alloxan-induced hyperglycemia leads to the development of emphysematous changes in combination with restriction. The vascular wall of muscular pulmonary vessels was thickened due to hypertrophy of the tunica media and tunica externa. The hypertrophy of lymphoid follicles and lymph nodes of the upper and lower mediastinum was observed in experimental animals.