تاثیر تمرین استقامتی بر سطح عامل نوروتروفیک مشتق از مغز ( bdnf) و گیرنده تیروزین کیناز b ( trkb) در هیپوکامپ موش های صحرایی نر ایسکمی شده

ﻣﻘﺪﻣﻪ: ﻋﺎﻣﻞ ﻧﻮروﺗﺮوﻓﯿﮏ ﻣﺸﺘﻖ از ﻣﻐﺰ (bdnf) ﺑﺎ اﺗﺼﺎل ﺑﻪ ﮔﯿﺮﻧﺪه ﺗﯿﺮوزﯾﻦ ﮐﯿﻨﺎز trkb) b) ﻣﯽﺗﻮاﻧﺪ اﺛﺮات ﻣﺤﺎﻓﻈﺖ ﮐﻨﻨﺪه ﻋﺼﺒﯽ داﺷﺘﻪ ﺑﺎﺷﺪ. ﺑﻨﺎﺑﺮاﯾﻦ ﻫﺪف از ﺗﺤﻘﯿﻖ ﺣﺎﺿﺮ ﺑﺮرﺳﯽ اﺛﺮ 8 ﻫﻔﺘﻪ ﺗﻤﺮﯾﻦ اﺳﺘﻘﺎﻣﺘﯽ ﺑﺮ bdnf و trkb در ﻫﯿﭙﻮﮐﺎﻣﭗ ﻣﻮشﻫﺎی ﺻﺤﺮاﯾﯽ ﻧﺮ اﯾﺴﮑﻤﯽ ﺷﺪه ﺑﻮد. روش ﮐﺎر: 48 ﺳﺮ ﻣﻮش ﺻﺤﺮاﯾﯽ ﻧﺮ ﻧﮋاد وﯾﺴﺘﺎر (ﺑﺎ ﺳﻦ 12 ﻫﻔﺘﻪ و ﻣﯿﺎﻧﮕﯿﻦ وزﻧﯽ 21/18 ±228/19 ﮔﺮم)، در 4 ﮔﺮوه ﺳﺎﻟﻢ ﮐﻨﺘﺮل، اﯾﺴﮑﻤﯽ ﮐﻨﺘﺮل، ﺳﺎﻟﻢ ﺗﻤﺮﯾﻦ، اﯾﺴﮑﻤﯽ ﺗﻤﺮﯾﻦ ﻗﺮار ﮔﺮﻓﺘﻨﺪ. ﺑﺮای اﻟﻘﺎی اﯾﺴﮑﻤﯽ، ﺷﺮﯾﺎن ﮐﺎروﺗﯿﺪ ﺑﺎ اﺳﺘﻔﺎده از ﮔﯿﺮهﻫﺎی ﻣﯿﮑﺮوﺳﺮﺟﺮی ﺑﻪ ﻣﺪت 45 دﻗﯿﻘﻪ ﻣﺴﺪود ﺷﺪ. ﮔﺮوهﻫﺎی ﺗﻤﺮﯾﻦ (ﺳﺎﻟﻢ و اﯾﺴﮑﻤﯽ) ﺑﺎ ﺳﺮﻋﺖ 30 ﻣﺘﺮ در دﻗﯿﻘﻪ (ﻣﻌﺎدل 70 درﺻﺪ vo2max)ﺑﻪ ﻣﺪت 30 دﻗﯿﻘﻪ در ﻫﺮ ﺟﻠﺴﻪ و 5 روز در ﻫﻔﺘﻪ روی ﻧﻮار ﮔﺮدان ﺗﻤﺮﯾﻦ ﮐﺮدﻧﺪ. ﺳﻄﺢ bdnf و trkb ﻫﯿﭙﻮﮐﺎﻣﭗ ﺑﺎ اﺳﺘﻔﺎده از روش اﻻﯾﺰا ﻣﻮرد ﺳﻨﺠﺶ ﻗﺮار ﮔﺮﻓﺖ. ﺗﺠﺰﯾﻪ و ﺗﺤﻠﯿﻞ دادهﻫﺎ ﺑﺎ اﺳﺘﻔﺎده از آزﻣﻮن ﺗﺤﻠﯿﻞ وارﯾﺎﻧﺲ ﯾﮏ ﻃﺮﻓﻪ و آزﻣﻮن ﺗﻌﻘﯿﺒﯽ ﺗﻮﮐﯽ اﻧﺠﺎم ﺷﺪ (0/05 ˂ p). ﯾﺎﻓﺘﻪﻫﺎ: ﺳﻄﺢ bdnf در ﻫﯿﭙﻮﮐﺎﻣﭗ ﻣﻮشﻫﺎی ﮔﺮوه اﯾﺴﮑﻤﯽ ﮐﻨﺘﺮل ﻧﺴﺒﺖ ﺑﻪ ﮔﺮوه ﺳﺎﻟﻢ ﮐﻨﺘﺮل و ﺳﺎﻟﻢ ﺗﻤﺮﯾﻦ ﺑﻪ ﻃﻮر ﻣﻌﻨﺎداری ﭘﺎﯾﯿﻦﺗﺮ ﺑﻮد (ﻣﻘﺎدﯾﺮ p ﺑﻪﺗﺮﺗﯿﺐ 0/002 و 0/001) وﻟﯽ ﺳﻄﺢ اﯾﻦ ﺷﺎﺧﺺ در ﮔﺮوه اﯾﺴﮑﻤﯽ ﺗﻤﺮﯾﻦ ﻧﺴﺒﺖ ﺑﻪ ﮔﺮوه اﯾﺴﮑﻤﯽ ﮐﻨﺘﺮل و ﺳﺎﻟﻢ ﮐﻨﺘﺮل ﺗﻔﺎوت ﻣﻌﻨﺎداری ﻣﺸﺎﻫﺪه ﻧﺸﺪ (ﻣﻘﺎدﯾﺮ p ﺑﻪﺗﺮﺗﯿﺐ 0/54 و 0/091). ﺑﯿﻦ ﺳﻄﺢ trkb در ﮔﺮوه اﯾﺴﮑﻤﯽ ﮐﻨﺘﺮل ﻧﺴﺒﺖ ﺑﻪ ﮔﺮوه ﺳﺎﻟﻢ ﮐﻨﺘﺮل و اﯾﺴﮑﻤﯽ ﺗﻤﺮﯾﻦ، ﺗﻔﺎوت ﻣﻌﻨﺎداری ﻣﺸﺎﻫﺪه ﻧﺸﺪ (0/05 > p) وﻟﯽ ﺳﻄﺢ اﯾﻦ ﺷﺎﺧﺺ در ﮔﺮوه ﺳﺎﻟﻢ ﺗﻤﺮﯾﻦ ﻧﺴﺒﺖ ﺳﺎﻟﻢ ﮐﻨﺘﺮل و اﯾﺴﮑﻤﯽ ﺗﻤﺮﯾﻦ ﺑﻪﻃﻮر ﻣﻌﻨﺎداری ﺑﺎﻻﺗﺮ ﺑﻮد (0/001 = p). ﻧﺘﯿﺠﻪﮔﯿﺮی: ﺑﻪ ﻧﻈﺮ ﻣﯽرﺳﺪ ﺗﻤﺮﯾﻦ اﺳﺘﻘﺎﻣﺘﯽ ﻣﯽﺗﻮاﻧﺪ از ﻃﺮﯾﻖ ﺑﻬﺒﻮد ﺳﻄﺢ bdnf و trkb در ﻫﯿﭙﻮﮐﺎﻣﭗ ﻣﻮشﻫﺎی اﯾﺴﮑﻤﯽ ﺷﺪه، ﺑﻪ ﺑﺎزﯾﺎﻓﺖ ﻧﻮرونﻫﺎی ﻋﺼﺒﯽ ﻣﺘﻌﺎﻗﺐ اﯾﺴﮑﻤﯽ ﮐﻤﮏ ﮐﻨﺪ و ﺑﻪ ﻋﻨﻮان ﯾﮏ روش درﻣﺎﻧﯽ ﻣﮑﻤﻞ در ﺑﯿﻤﺎران اﯾﺴﮑﻤﯽ ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗﺮار ﮔﯿﺮد.

Effect of Endurance Training on Brain Derived Neurotrophic Factor (BDNF) and Tyrosine Kinase B (Trkb) Level in Hippocampus of Ischemic Induced Male Rats

Introduction: Brain derived neurotrophic factor (BDNF) have neuroprotective effect through binding with tyrosine kinase B (TrkB). Thus the Aim of the present study was to investigate the effects of eight weeks endurance training on BDNF and TrkB levels in the hippocampus of ischemic induced male rats. Methods: 40 Male wistar rats (12 weeks old and 228.19 ±21.18g) were divided into four groups, including: ischemic control, ischemic training, healthy control, healthy training. To induce ischemia, carotid artery is clamped with microsurgery clamp for 45 minutes. Training groups (healthy and ischemic), trained with 30m/min (70% VO2max), 30min/day, and 5 days/week on the treadmill. BDNF and TrkB levels of the hippocampus were measured using ELISA method.For data analysis, oneway ANOVA and post hoc Tukey tests were performed at a significance level of P˂0.05. Results: The results showed that BDNF levels in hippocampus of ischemic control group were significantly lower than healthy control and healthy training group (P values 0.001, 0.002 respectively). No significant differences were found between BDNF levels in ischemic training with ischemic control and healthy control group (p values 0.54, 0.091 respectively) and No significant differences were found between TrkB levels in ischemic control with healthy control and ischemic control group (p values 0.675, 0.821 respectively). TrkB level in healthy training group was significantly higher than healthy control, healthy training groups (P=0.001). Conclusions: Based on these results, it seems that endurance training can have neuroprotective effect through increasing the level of BDNF and TrkB level in hippocampus of ischemic rats and can be studied as a complementary therapy in ischemic disease.