Dimorphic evaluation of hippocampal changes in rat model of demyelination: A comparative functional, morphometric, and histological study

Background Multiple sclerosis (MS) is the most common autoimmune disease. Progressive depletion of the brain and spinal cord tissue appears at the onset of the disease. Several studies have shown the increased size of the ventricles of the brain and decreases in the area of the corpus callosum and the width of the brain. Other important symptoms of this disease are cognitive, learning, and memory disorders. Aim The aim of this study was to compare morphometric, histological, and functional changes in the demyelination model in both sexes. Materials and methods In this experimental study, male and female Wistar rats were studied in four experimental groups. Demyelination was induced by the injection of ethidium bromide in the ventricular region. The chronic effect of demyelination on spatial memory, movement, and coordination was investigated using the Morris Water Maze (MWM), and clinical and balance beam tests, respectively. Myelin degradation, cell death and neurogenesis were estimated using Luxol Fast Blue staining and immunohistochemistry (Caspase-3 and Nestin markers). In addition, morphometric findings were recorded for the brain and hippocampus (weight, volume, length, width). Result Demyelination increased the time and distance index and decreased the residence time in the target quarter in the water maze test (p < .001). It also increases the neuromuscular and modified neurological severity score (p < .01). Demyelination increases caspase-3 (p < .05) expression and decreases Nestin expression (p < .001), which are directly related to the extent of damage. Conclusion This study showed an interaction between hippocampal structural and functional networks in explaining spatial learning and memory in the early stages of MS

Combined treatment of high-intensity interval training with neural stem cell generation on contusive model of spinal cord injury in rats

IntroductionSpinal cord injury (SCI) leads to inflammation, axonal degeneration, and gliosis. A combined treatment of exercise and neural stem cells (NSC) has been proposed to improve neural repair. This study evaluated a combined treatment of high-intensity interval training (HIIT) with NSC generation from adipose-derived stem cells (ADSCs) on a contusive model of SCI in rats. Materials and MethodsIn vitro, rat ADSCs were isolated from the perinephric regions of Sprague-Dawley rats using enzymatic digestion. The ADSCs were transdifferentiated into neurospheres using B27, EGF, and bFGF. After production of NSC, they were labeled using green fluorescent protein (GFP). For the in vivo study, rats were divided into eight groups: control group, sham operation group, sham operation + HIIT group, sham operation + NSC group, SCI group, SCI + HIIT group, SCI + NSC group, and SCI/HIIT/NSC group. Laminectomy was carried out at the T12 level using the impactor system. HIIT was performed three times per week. To assess behavioral function, the Basso-Beattie-Bresnahan (BBB) locomotor test and H-reflex was carried out once a week for 12 weeks. We examined glial fibrillary acidic protein (GFAP), S100 beta, and NF200 expression. ResultsNSC transplantation, HIIT and combined therapy with NSC transplantation, and the HIIT protocol improved locomotor function with decreased maximum H to maximum M reflexes (H/M ratio) and increased the Basso-Beattie-Bresnahan score. ConclusionCombined therapy in contused rats using the HIIT protocol and neurosphere-derived NSC transplantation improves functional and histological outcomes

Effect of crocin on inhibitory avoidance memory, balance and explorative behaviours following cisplatin administration in rat

Background: A lot of studies indicate that cancer chemotherapy results in memory and motor impairment immediately following therapy. On the other side, crocin as the chemical constituent isolated from the Saffron is effective on memory and motor impairement. In this study, the effect of crocin on memory and motor impairment induced by cisplatin injection was studied in adult male rats. Materials and Methods: In this study, male Wistar rats (n=50) were divided into 5 groups: Control, Sham, Cisplatin (2 mg/kg/week for 21 days), Crocin (30 mg/kg for 21 days) and Cisplatin+Crocin. Sham group was administrated with Saline. Then, inhibitory avoidance memory, balance and exploratory behaviors were assessed by shuttle box, rotarod and open field apparatus, respectively. Results: Crocin improved memory impairment induced by cisplatin (P&lt;0.01). Cisplatin also impaired balance in rotarod test. Rearing frequency and total distance traveled in open field test were significantly decreased (P&lt;0.001 and P&lt;0.05, respectively) compared to Control group. Conclusion: We conclude that crocin injection following the use of anticancer drugs (e.g. cisplatin) might have a protective effect against the cisplatin-induced impairement in cognitive function, balance and explorative behavior