The leaves of Eucalyptus globulus (eucalyptus) are used for the treatment of
diabetes mellitus in traditional medicine. The aim of this study was to evaluate
the effects of eucalyptus on streptozotocin (STZ)-induced damage in pancreatic
islands by stereological methods. Fifty mature normoglycaemic male Wistar
rats, weighing 200-250 g, were selected and randomly divided into 5 groups
(n = 10): control; STZ-induced diabetic (D) - by intraperitoneal injection of
60 mg/kg streptozotocin; treated control (TC); and treated diabetic (TD1, 2),
respectively, received 20 and 62.5 g/kg of eucalyptus in their diet, and 2.5 g/L
aqueous extract of eucalyptus in their drinking water from one week after
induction of diabetes. After four weeks of the experiment, stereological estimation
of volume density and total volume of islets and beta cells, volume-weighted mean islet volume, mass of the islets and pancreas, and total number
of islets were carried out. Administration of eucalyptus significantly decreased
the weight loss and increase of water and food intake in the treated
diabetic groups in comparison to the STZ-induced diabetic (D) group. Volume
density and total volume of islets, volume-weighted mean islet volume, mass
of islets, and mass of pancreas of both treated diabetic groups were higher
than the D group. In TD2, these stereological parameters increased significantly
compared to the D group (p < 0.001). Volume density and total volume of
beta cells increased 21% and 65%, respectively, in the TD2 group, but it was
not statistically significant compared to the diabetic group (p > 0.05).
The results suggested that Eucalyptus globulus with a dose-dependent manner
ameliorates diabetic states by partial restoration of pancreatic beta cells
and repair of STZ-induced damage in rats. This study suggests a beneficial
effect of eucalyptus in the treatment of diabetes. (Folia Morphol 2010; 69, 2:
112-118