ABSTRACT
The orexin 2 receptor plays a central role in maintaining sleep and wakefulness. Recently, it has been shown that sleep and wakefulness orchestrate the proliferation and differentiation of oligodendrocytes. Here, we explored the role of a selective orexin 2 receptor antagonist (JNJ-10397049) in proliferation and differentiation of neural progenitor cells (NPCs). We evaluated the proliferation potential of NPCs after exposure to different concentrations of JNJ-10397049 by using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide and neurosphere assays. Moreover, the expression of differentiation markers was assessed by immunocytochemistry and real-time polymerase chain reaction. JNJ-10397049 significantly increased the proliferation of NPCs at lower concentrations. In addition, orexin 2 receptor antagonist facilitated progression of differentiation of NPCs towards oligodendroglial lineage by considerable expression of Olig2 and 2’,3’-cyclicnucleotide 3’-phosphodiesterase as well as decreased expression of nestin marker. The results open a new avenue for future investigations in which the production of more oligodendrocytes from NPCs is needed.
ABSTRACT
Following acute spinal cord injury (SCI), excessive recruitment of neutrophils can result in inflammation, neural tissue loss and exacerbation of neurological outcomes. Ibrutinib is a bruton’s tyrosine kinase inhibitor in innate immune cells such as the neutrophils that diminishes their activation and influx to the site of injury. The present study evaluated the efficacy of ibrutinib administration in the acute phase of SCI on neural tissue preservation and locomotor recovery. Ibrutinib was delivered intravenously at 3.125 mg/kg either immediately, 12 hours after, or both immediately and 12 hours after SCI induction in adult male C57BL/6 mice. Neutrophil influx into the lesion area was evaluated 24 hours following SCI using light microscopy and immunohistochemistry methods. Animals’ body weight changes were recorded, and their functional motor recovery was assessed based on the Basso mouse scale during 28 days after treatment. Finally, spinal cord lesion volume was estimated by an unbiased stereological method. While animals’ weight in the control group started to increase one week after injury, it stayed unchanged in treatment groups. However, the double injection of ibrutinib led to a significantly lower body weight compared to the control group at 4 weeks post-injury. Mean neutrophil counts per visual field and the lesion volume were significantly decreased in all ibrutinib-treated groups. In addition, ibrutinib significantly improved locomotor functional recovery in all treated groups, especially in immediate and double-injection groups. Neural tissue protection and locomotor functional recovery suggest ibrutinib treatment as a potent immunotherapeutic intervention for traumatic SCI that warrants clinical testing.
ABSTRACT
Following acute spinal cord injury (SCI), excessive recruitment of neutrophils can result in inflammation, neural tissue loss and exacerbation of neurological outcomes. Ibrutinib is a bruton’s tyrosine kinase inhibitor in innate immune cells such as the neutrophils that diminishes their activation and influx to the site of injury. The present study evaluated the efficacy of ibrutinib administration in the acute phase of SCI on neural tissue preservation and locomotor recovery. Ibrutinib was delivered intravenously at 3.125 mg/kg either immediately, 12 hours after, or both immediately and 12 hours after SCI induction in adult male C57BL/6 mice. Neutrophil influx into the lesion area was evaluated 24 hours following SCI using light microscopy and immunohistochemistry methods. Animals’ body weight changes were recorded, and their functional motor recovery was assessed based on the Basso mouse scale during 28 days after treatment. Finally, spinal cord lesion volume was estimated by an unbiased stereological method. While animals’ weight in the control group started to increase one week after injury, it stayed unchanged in treatment groups. However, the double injection of ibrutinib led to a significantly lower body weight compared to the control group at 4 weeks post-injury. Mean neutrophil counts per visual field and the lesion volume were significantly decreased in all ibrutinib-treated groups. In addition, ibrutinib significantly improved locomotor functional recovery in all treated groups, especially in immediate and double-injection groups. Neural tissue protection and locomotor functional recovery suggest ibrutinib treatment as a potent immunotherapeutic intervention for traumatic SCI that warrants clinical testing.
ABSTRACT
Introduction: Alzheimer's disease [AD] is one of the most common neurodegenerative disorders, which has much benefited from animal models to find the basics of its pathophysiology. In our previous work [Haghani, Shabani, Javan, Motamedi, and Janahmadi, 2012], a non-transgenic rat model of AD was used in electrophysiological studies. However, we did not investigate the histological aspects in the mentioned study
Methods: An AD model was developed through bilateral injection of amyloid-beta peptides [Abeta] into the frontal cortices. Behavioral and histological methods were used to assess alterations in the memory and [ultra]structures. Furthermore, melatonin has been administered to assess its efficacy on this AD model
Results: Passive avoidance showed a progressive decline in the memory following Abeta injection. Furthermore, Nissl staining showed that Abeta neurotoxicity caused shrinkage of the CA1 pyramidal neurons. Neurodegeneration was clearly evident from Fluoro-jade labeled neurons in Abeta treated rats. Moreover, higher NF-kappaB immunoreactive CA1 pyramidal neurons were remarkably observed in Abeta treated rats. Ultrastructural analysis using electron microscopy also showed the evidence of subcellular abnormalities. Melatonin treatment in this model of AD prevented Abeta- induced increased NF-kappaB from immunoreaction and neurodegeneration
Discussion: This study suggests that injection of Abeta into the frontal cortices results in the memory decline and histochemical disturbances in CA1 pyramidal neurons. Furthermore, melatonin can prevent several histological changes induced by Abeta
Subject(s)
Animals, Laboratory , Peptide Fragments , Amyloid beta-Peptides , Alzheimer Disease , Frontal Lobe , Brain Diseases , Memory , Rats, Wistar , MelatoninABSTRACT
Introduction: Several studies indicate that estrogen use increase performance on some tests of cognition especially in postmenopausal women. These steroids have many side effects, thus, other estrogenic agents with fewer side effects are needed to develop alternative treatment strategies. The main objection of this study was to evaluate the effects of different doses of dietary soy meals [with or without isoflavone] on spatial learning and memory in ovariectomized [OVX] rats. Methods: Female Wistar rats with the exception of intact group were ovariectomized at the first line of study. Subjects were divided into six groups. The control group rats [c] were gonadally intact, while the others were OVX. OVX groups received normal diet [0], treated with 10 gr soy [10], 20 gr soy [20], 10 gr isoflavone free soy [-10] or 20 gr isoflavone free soy [-20] in daily diet for four weeks. The spatial learning and memory were tested using Morris water maze. Rats were trained in water maze to find a hidden escape Platform. Rats received 6 blocks that each block consisted of 3 trials. Following acquisition trials, one probe trial were conducted in which the platform was removed. Results: Soy meal diet [with or without isoflavone] in ovariectomized rats caused improvement of performance across 18 trials of Acquisition. Discussion: Our results suggest that soy consumption apart from containing isoflavone or not is a potential alternative to estrogen in the improvement of cognition