Abnormalities in the brain of streptozotocin-induced type 1 diabetic rats revealed by diffusion tensor imaging

Abstract

Diabetes mellitus affects the brain. Both type 1 and type 2 diabetic patients are associated with white matter (WM) damage observable to diffusion tensor imaging (DTI). The underlying histopathological mechanisms, however, are poorly understood. The objectives of this study are 1) to determine whether streptozotocin (STZ)-induced type 1 diabetes is associated with WM damage observable to DTI; and 2) to understand the pathophysiological aspects underlying STZ-induced brain injuries. Male Sprague–Dawley rats received a single intraperitoneal injection of STZ (62 mg/kg). DTI was used to assess brain abnormalities at 4 weeks after induction, combined with histological assessments and ultrastructural analysis. Compared to controls, the STZ-induced rats showed significantly reduced fractional anisotropy (FA) in the motor/somatosensory cortex and striatum. Histologically, the cortex and striatum of the diabetic animals are characterized by demyelination and axonal degradation. In conclusion, STZ-induced diabetes is associated with striatal/cortical injuries observable to DTI. The DTI abnormalities are likely manifestations of demyelination and axonal degradation in the affected brain regions, and can potentially be used as surrogates for evaluating diabetic brain injuries.

Fish oil and wheat germ oil supplementation modulates brain injury in streptozotocin‐induced diabetic rats

“…The histopathological changes in the brain in the diabetic rat group are in accordance with the study of Huang et al, who reported that diabetes reduced fatty acids in the striatum and motor/somatosensory cortex as early as 4 weeks after diabetes induction. Moreover, demyelination, axonal degradation, and neuronal dysfunction are observed in various brain regions, and these are associated with the inflammation and oxidative stress that affect hippocampal synaptic plasticity and apoptosis of neurons .…”

Wistar rats with long-term streptozotocin-induced type 1 diabetes mellitus replicate the most relevant clinical, biochemical, and hematologic features of human diabetes / Sobolanii Wistar cu diabet zaharat tip 1 indus cu streptozotocina reproduc cele mai relevante caracteristici clinice, biochimice si hematologice ale diabetului uman

“…This appears to contradict previous studies reporting decreased bodyweight with advancing age in diabetics (14,15). However, in these latter studies, the follow-up period was significantly shorter.…”

“…The second phase, of severe hypoglycemia, was incriminated in the early deaths recorded following STZ administration. This hypothesis is further supported by the fact that administration of 5% dextrose efficiently prevented these early deaths (14). However, our results suggest that early free access to food may be just as effective in preventing early mortalities.…”

Resveratrol prevents akinesia and restores neuronal tyrosine hydroxylase immunoreactivity in the substantia nigra pars compacta of diabetic rats

“…However, resveratrol was able to protect against akinesia development during the time course of the diabetes. This result demonstrates an unprecedented positive effect of resveratrol on this locomotor deficit, possibly due to its capability to attenuate some pathological mechanisms in brain regions responsible for motor control, such as the basal ganglia and cerebellum (Ates et al, 2007;Biessels et al, 1994;Cheema et al, 2011;Huang et al, 2012;Sima, 2010;Venturini et al, 2010).…”