Research code: مقاله مستخرج از رساله دکتری است
Ethics code: IR.IAU.TABRIZ.REC.1404.092
Clinical trials code: مقاله مستخرج از رساله دکتری است
Farzad Seifi1 
, Farzad Zehsaz *2 , Miralireza Nourazar1 , Roghayeh Poozesh Jadidi1 , Mehri Ghahremani1
, Farzad Zehsaz *2 , Miralireza Nourazar1 , Roghayeh Poozesh Jadidi1 , Mehri Ghahremani1
1- Islamic Azad University, Islamic Azad University
2- Islamic Azad University, Islamic Azad University ,farzad.zehsaz@iau.ac.ir
2- Islamic Azad University, Islamic Azad University ,
Abstract: (832 Views)
Introduction
It is quite clear that menopause can lead to mitochondrial genome mutations and cell death as a result of increased oxidative stress [8]. Estrogen deficiency, following natural menopause or surgical menopause (oophorectomy), is associated with increased production of lipid peroxides and a deficiency of antioxidant defense, leading to a pathogenesis that commonly affects postmenopausal women.
In light of the above, researchers are continuously seeking to discover a method or methods to reduce the negative effects of menopause on individual and social life, one of which is exercise and physical activity. The importance of exercise and physical activity is such that regular exercise and physical activity have been shown to be associated with significant health benefits and a significant reduction in CVD risk [14].
However, a review of studies suggests that the adaptive response to exercise training is a complex process that depends on the mode, intensity, and duration of exercise. Aerobic exercise training is the most common type of exercise performed in studies. High-intensity interval training (HIIT) has also recently gained attention as a time-efficient training mode that provides multiple benefits. Recent studies suggest that HIIT may exhibit cardioprotective effects as it is associated with reduced cardiac apoptosis [15].
Meanwhile, red clover, known for its high phytoestrogen content, is beginning to gain traction as a novel therapeutic intervention for postmenopausal women because it is rich in the isoflavones biochanin A and formonentin. Previous research, although limited, has shown that supplementation with red clover extract can have positive effects on vascular function in postmenopausal women [18, 19]. Some evidence suggests improved antioxidant and vasodilator properties [20] as well as atherogenic adhesion molecules, while others show no effect of red clover extract on inflammatory markers [21] or coagulation factors [22].
Therefore, this study seeks to answer the question of whether aerobic exercise and red clover supplementation affect cardiac tissue oxidative markers in ovariectomized rats.
Method
To conduct the present basic-applied and experimental research, 48 ovariectomized rats were obtained from the Laboratory Animal Breeding and Maintenance Center of Tabriz University of Veterinary Sciences. After one week of being kept in the Tabriz Veterinary University animal house under controlled conditions, they were randomly divided into groups: 1. Healthy control 2. Sham surgery 3. Ovariectomy 4. Ovariectomy + red clover supplement 5. Ovariectomy + aerobic exercise 6. Ovariectomy + red clover supplement + aerobic exercise.
The interval aerobic exercise training protocol was implemented for eight weeks, five sessions per week, with progressive intensity and duration, and with the principle of overload. The speed of the training program was 15 meters per minute in the first week. It increased to 16 meters per minute from the second week, 17 meters per minute from the third week, and 18 meters per minute from the fourth to the eighth week. The duration of training was increased daily from the first to the eighth week, from 30 minutes in the first week to 34 minutes in the second week and 38 minutes in the third week, and from the fourth to the eighth week to 40 minutes. To warm up, they ran for 3 minutes at a speed of 6 meters per minute at the beginning of each session. To cool down, the rats ran on a treadmill for 3 minutes at a speed of 6 meters per minute. The entire training program was performed without incline [23].
Two weeks after ovariectomy, administration of red clover extract was started. 1 gram of clover extract and 1 gram of red clover seed extract were mixed with 5.8 cc of distilled water and heated gently on a magnetic heater for 30 minutes. Then, each mouse was fed 0.5 ml/kg of the extract daily for 8 weeks by gavage. The red clover extract and aerobic exercise treatment group also received the extract at the same dose and exercised on a treadmill for eight weeks, just like the exercise group.
At the end of the experiment, the mice were anesthetized with ketamine hydrochloride (90 mg/kg) and xylazine (10 mn/kg) to examine the research variables. Finally, descriptive statistics (mean and standard deviation), Shapiro-Wilk, one-way analysis of variance and Tukey's post hoc test were used to statistically analyze the data using SPSS version 26 software at a significance level of p < 0.05.
Results
The intervention significantly decreased SOD, GPx, and significantly increased MDA in rats compared to the control group. Aerobic exercise training + red clover supplementation interventions had the greatest effect on increasing SOD, GPx, TAC, and decreasing MDA compared to aerobic exercise training and red clover supplementation. The evaluation of cardiac tissue apoptosis indices showed that the expression of pro-Caspase3 protein in cardiac tissue of ovariectomized rats was significantly decreased compared to the Sham group and the expression of Cleaved Caspase3 protein was increased. There was no statistically significant difference between pro-Caspase3 and Cleaved Caspase3 among the OVX+E, OVX+M, and OVX+E+M groups.
Discussion
The prevalence of chronic diseases such as high blood pressure, diabetes and cardiovascular diseases increases from the age of 40 onwards. The role of exercise in a healthy lifestyle is important for reducing the incidence of cancer and cardiovascular diseases. Studies have shown that regular walking and running for 10 months is significantly effective in improving obesity indicators including weight, body mass index and waist circumference. It has been reported that excessive body fat accumulation contributes to the induction of an inflammatory response, as it causes symptoms of decreased insulin sensitivity and the expression of insulin-resistant cytokines (26). Aerobic exercise and meditation are also effective in reducing anxiety and depression. Depression and anxiety are much more pronounced in CVD patients than in healthy individuals (26).
On the other hand, the use of herbal medicines has been increasing in recent years in Asian and Western countries. Their integration into the medical care system has been encouraged by the World Health Organization. Despite the widespread use of a number of herbal medicines for a wide range of diseases in humans, evidence supporting their claimed medicinal benefits is scarce. To date, only a very small number of herbal medicines from over 11,000 plant species have undergone double-blind, randomized, controlled, multicenter clinical trials [27].
Overall, this study provides preliminary evidence that red clover and aerobic exercise training exert cardioprotective effects by inhibiting oxidative stress-induced cardiac damage. However, it should be noted that almost all potent antioxidants that demonstrate strong efficacy in animal studies have very limited therapeutic effects in humans. This could be due to species differences in the pathogenesis pathways of oxidative damage, leading to different responses to antioxidants in distinct species. Differences in dosage and treatment regimens may also contribute to this species-dependent response. Therefore, caution should be exercised when applying the findings from the current study to the clinical situation.
It is quite clear that menopause can lead to mitochondrial genome mutations and cell death as a result of increased oxidative stress [8]. Estrogen deficiency, following natural menopause or surgical menopause (oophorectomy), is associated with increased production of lipid peroxides and a deficiency of antioxidant defense, leading to a pathogenesis that commonly affects postmenopausal women.
In light of the above, researchers are continuously seeking to discover a method or methods to reduce the negative effects of menopause on individual and social life, one of which is exercise and physical activity. The importance of exercise and physical activity is such that regular exercise and physical activity have been shown to be associated with significant health benefits and a significant reduction in CVD risk [14].
However, a review of studies suggests that the adaptive response to exercise training is a complex process that depends on the mode, intensity, and duration of exercise. Aerobic exercise training is the most common type of exercise performed in studies. High-intensity interval training (HIIT) has also recently gained attention as a time-efficient training mode that provides multiple benefits. Recent studies suggest that HIIT may exhibit cardioprotective effects as it is associated with reduced cardiac apoptosis [15].
Meanwhile, red clover, known for its high phytoestrogen content, is beginning to gain traction as a novel therapeutic intervention for postmenopausal women because it is rich in the isoflavones biochanin A and formonentin. Previous research, although limited, has shown that supplementation with red clover extract can have positive effects on vascular function in postmenopausal women [18, 19]. Some evidence suggests improved antioxidant and vasodilator properties [20] as well as atherogenic adhesion molecules, while others show no effect of red clover extract on inflammatory markers [21] or coagulation factors [22].
Therefore, this study seeks to answer the question of whether aerobic exercise and red clover supplementation affect cardiac tissue oxidative markers in ovariectomized rats.
Method
To conduct the present basic-applied and experimental research, 48 ovariectomized rats were obtained from the Laboratory Animal Breeding and Maintenance Center of Tabriz University of Veterinary Sciences. After one week of being kept in the Tabriz Veterinary University animal house under controlled conditions, they were randomly divided into groups: 1. Healthy control 2. Sham surgery 3. Ovariectomy 4. Ovariectomy + red clover supplement 5. Ovariectomy + aerobic exercise 6. Ovariectomy + red clover supplement + aerobic exercise.
The interval aerobic exercise training protocol was implemented for eight weeks, five sessions per week, with progressive intensity and duration, and with the principle of overload. The speed of the training program was 15 meters per minute in the first week. It increased to 16 meters per minute from the second week, 17 meters per minute from the third week, and 18 meters per minute from the fourth to the eighth week. The duration of training was increased daily from the first to the eighth week, from 30 minutes in the first week to 34 minutes in the second week and 38 minutes in the third week, and from the fourth to the eighth week to 40 minutes. To warm up, they ran for 3 minutes at a speed of 6 meters per minute at the beginning of each session. To cool down, the rats ran on a treadmill for 3 minutes at a speed of 6 meters per minute. The entire training program was performed without incline [23].
Two weeks after ovariectomy, administration of red clover extract was started. 1 gram of clover extract and 1 gram of red clover seed extract were mixed with 5.8 cc of distilled water and heated gently on a magnetic heater for 30 minutes. Then, each mouse was fed 0.5 ml/kg of the extract daily for 8 weeks by gavage. The red clover extract and aerobic exercise treatment group also received the extract at the same dose and exercised on a treadmill for eight weeks, just like the exercise group.
At the end of the experiment, the mice were anesthetized with ketamine hydrochloride (90 mg/kg) and xylazine (10 mn/kg) to examine the research variables. Finally, descriptive statistics (mean and standard deviation), Shapiro-Wilk, one-way analysis of variance and Tukey's post hoc test were used to statistically analyze the data using SPSS version 26 software at a significance level of p < 0.05.
Results
The intervention significantly decreased SOD, GPx, and significantly increased MDA in rats compared to the control group. Aerobic exercise training + red clover supplementation interventions had the greatest effect on increasing SOD, GPx, TAC, and decreasing MDA compared to aerobic exercise training and red clover supplementation. The evaluation of cardiac tissue apoptosis indices showed that the expression of pro-Caspase3 protein in cardiac tissue of ovariectomized rats was significantly decreased compared to the Sham group and the expression of Cleaved Caspase3 protein was increased. There was no statistically significant difference between pro-Caspase3 and Cleaved Caspase3 among the OVX+E, OVX+M, and OVX+E+M groups.
Discussion
The prevalence of chronic diseases such as high blood pressure, diabetes and cardiovascular diseases increases from the age of 40 onwards. The role of exercise in a healthy lifestyle is important for reducing the incidence of cancer and cardiovascular diseases. Studies have shown that regular walking and running for 10 months is significantly effective in improving obesity indicators including weight, body mass index and waist circumference. It has been reported that excessive body fat accumulation contributes to the induction of an inflammatory response, as it causes symptoms of decreased insulin sensitivity and the expression of insulin-resistant cytokines (26). Aerobic exercise and meditation are also effective in reducing anxiety and depression. Depression and anxiety are much more pronounced in CVD patients than in healthy individuals (26).
On the other hand, the use of herbal medicines has been increasing in recent years in Asian and Western countries. Their integration into the medical care system has been encouraged by the World Health Organization. Despite the widespread use of a number of herbal medicines for a wide range of diseases in humans, evidence supporting their claimed medicinal benefits is scarce. To date, only a very small number of herbal medicines from over 11,000 plant species have undergone double-blind, randomized, controlled, multicenter clinical trials [27].
Overall, this study provides preliminary evidence that red clover and aerobic exercise training exert cardioprotective effects by inhibiting oxidative stress-induced cardiac damage. However, it should be noted that almost all potent antioxidants that demonstrate strong efficacy in animal studies have very limited therapeutic effects in humans. This could be due to species differences in the pathogenesis pathways of oxidative damage, leading to different responses to antioxidants in distinct species. Differences in dosage and treatment regimens may also contribute to this species-dependent response. Therefore, caution should be exercised when applying the findings from the current study to the clinical situation.
Type of Study: Research |
Subject:
Exercise Physiology
Send email to the article author
