Protective Effect Of Sima Gene Involved In Hypoxic Combined Regular Exercise On Cardiac Dysfunction And Sleep-wake Rhythm Disorder Caused By Acute Hypoxia

1 Objective In this study,Drosophila was used as a model organism,and the Sima gene was knocked down by the Hand-Gal4 system.Hypoxia and exercise intervention were performed on the Drosophila by a hypoxic device or an exercise device.To explore the protective effect of this intervention on acute hypoxia-induced cardiac dysfunction and whether Sima gene is involved in the protection of cardiac dysfunction.For the three-week hypoxic exercise intervention in Drosophila,the indicators were detected after the intervention: cardiac function,circadian rhythm,SIMA m RNA expression,data were obtained and statistical analysis was performed.Through the discussion on the protective effect of Sima gene involved in hypoxic combined regular exercise on cardiac dysfunction caused by acute hypoxia,it provides a theoretical basis for studying the protective effect of hypoxic exercise intervention on cardiac dysfunction caused by acute hypoxia.The prognosis of patients with vascular disease provides a practical basis,and also provides a theoretical basis for studying the protective mechanism of Sima gene involved in cardiac dysfunction.2 Methods Virgo fly V106187 was crossed with male fly W1118 male fly to obtain F1 generation of virgin flies as a gene normal expression of Drosophila(Sima-RNAi/+ Drosophila)was divided into: normoxia control group(NC),normal group(N),hypoxia group(H),exercise group(E)Hypoxic exercise group(HE);virgin fly v106187 and male fly 48396 were crossed to obtain F1 generation virgin fly generation as Sima gene knockdown Drosophila(Hand>Sima RNAi Drosophila)was divided into: knockdown normoxia control group(NCKd),knockdown group(Kd),Hypoxic knockdown group(HKd),exercise knockdown group(EKd),hypoxic exercise knockdown group(HEKd).The F1 generations of the two groups were used as experimental fruit flies of 800/group,20/tube,and all the fruit flies were placed in the HWS intelligent constant temperature and humidity(Ningbo Jiangnan Instrument Factory)Drosophila incubator,maintaining the temperature at 25 degrees Celsius.50% humidity,12 hours day and night cycle feeding.In the exercise group,the third generation of Drosophila exercise device was used for exercise,from 14:00 to 16:00 p.m.every day.The hypoxic group was treated with hypoxic device from 9:00 to 13:00 a.m.every day.Both exercise group and hypoxia group started from the second day to the end of the 22 nd day.Index detection: 60 Drosophila melanogaster were randomly selected from each group to detect the m RNA expression of SIMA by RT-PCR to construct Hand>Sima RNAi strain.Each group randomly selected 30 Drosophila for M-mood cardiac function test.Cardiac pumping function(fractional shortening),rhythm function(fibrillations,arrhythmia index,diastolic interval arrhythmia index,systolic interval arrhythmia index),32 Drosophila were taken for circadian rhythm monitoring(nighttime sleep time,nighttime deep sleep time),the number of daytime activities,the number of activities per minute during the daytime awakening state).3 Results 3.1 Detection results of RT-pcr Sima-RNAi/+ and Hand>Sima RNAi Drosophila were treated with hypoxia under the same conditions to detect the expression of RT-PCR SIMA m RNA.Compared with Sima-RNAi/+(normal gene expression group),Hand>Sima RNAi(gene knockout group)showed a 35% decrease in the expression of Sima gene in cardiac tube,which proved that the Sima gene knockdown strain of Drosophila F1 was successfully constructed.3.2 Detection of Sima Gene Expression in Drosophila Heart Induced by Hypoxia and Exercise The expression of Sima gene in H,E and HE groups was less than that in HKd,EKd and HEKd groups.Secondly,in Sima-RNAi/+ Drosophila melanogaster,the expression of Sima gene in group H and E was lower than that in group N(P < 0.05),and that in group HE was higher than that in group N(P < 0.05).Hand > Sima RNAi Drosophila,HKd group,EKd group and HEKd group were significantly higher than Kd group(P < 0.01).3.3 Detection results of acute hypoxia on cardiac function Compared with NC group,the fractional shortening of N group was lower than that of NC group(P < 0.01),while the fibrillation,arrhythmia index,diastolic and systolic interval arrhythmia index were higher than that of NC group(P < 0.01).Compared with NCKd group,the fractional shortening of Kd group was lower(P < 0.01),while the fibrillation,arrhythmia index,diastolic and systolic interval arrhythmia indexin were higher(P < 0.01).3.4 Detection results of protective effect of Sima gene on cardiac function Compared with group N,the fractional shortening of Kd group was significantly lower than that of group N(P < 0.01),fibrillation,arrhythmia index,diastolic and systolic interval arrhythmia indexin were higher than that of group N(P<0.01),and Sima gene expression in group N was significantly higher than that in group Kd(P < 0.01).3.5 Detection results of the effect of Sima gene induced by hypoxic exercise on cardiac pumping function In Hand > Sima RNAi Drosophila,the expression of SIMA m RNA in HKd group was higher than that in Kd group(P < 0.05),and the expression of SIMA m RNA in HKd group was higher than that in Kd group(P < 0.01).In Sima-RNAi/+ Drosophila,the fractional shortening in group E was higher than that in group N(P < 0.01),while the expression of SIMA m RNA in group E was lower than that in group N(P < 0.05);in group Hand > Sima RNAi,the expression of SIMA m RNA in group EKd was higher than that in group Kd(P < 0.01),and the expression of SIMA m RNA in group EKd was higher than that in group Kd.The expression of SIMA m RNA in HE group and HEKd group was significantly higher than that in N group and Kd group(P < 0.01).The expression of SIMA m RNA in HE group and HEKd group was higher than that in N group and Kd group(P < 0.01).3.6 Hypoxia and Exercise Induced Sima Gene on Drosophila Heart Rhythm In Sima-RNAi/+Drosophila melanogaster,the fibrillation and diastolic interval arrhythmia indexin group H were significantly lower than those in group N(P < 0.01),while the expression of SIMA m RNA in group N was lower than that in group H(P < 0.05);in Hand > Sima RNAi Drosophila,the fibrillation,heart rate irregularity index,diastolic interval arrhythmia index and systolic interval arrhythmia index.in group HKd were significantly lower than those in group Kd.The expression of SIMA m RNA in Kd group was lower than that in HKd group(P < 0.01).In Sima-RNAi/+Drosophila melanogaster,the fibrillation and diastolic interval arrhythmia indexin group E were significantly lower than those in group N(P<0.01,P<0.05),while the expression of SIMA m RNA in group N was significantly lower than that in group E(P<0.05);in Hand>Sima RNAi Drosophila melanogaster,the fibrillation,heart rate irregularity index and diastolic interval arrhythmia indexin group EKd were significantly lower than those in group Kd(P<0.01),and SIMA m RNA expression in Kd group was lower than that in EKd group(P < 0.01).Fibrillation,heart rate irregularity index,diastolic interval arrhythmia indexand systolic interval arrhythmia index.in HE group were significantly lower than those in N group(P < 0.01).The expression of SIMA m RNA in group N was lower than that in group HE(P < 0.01);the expression of SIMA m RNA in group HEKd was lower than that in group Kd(P < 0.01);the expression of SIMA m RNA in group HEKd was lower than that in group HEKd(P < 0.01).3.7 Effect of Acute Hypoxia on Sleep-Awakening Rhythm in Fruit fly Compared with NC group,the number of deep sleep at night and the number of activities per minute in daytime waking state were significantly lower than NC group(P < 0.05,P < 0.01).Compared with NCKd group,the number of sleep at night,the number of deep sleep at night,the number of activities during daytime and the number of activities per minute in daytime waking state in Kd group were significantly lower than that in NCKd group(P < 0.01).The daytime sleep time and deep sleep in Kd group were significantly higher than those in night sleep time and deep sleep(P < 0.01).3.8 Test results of effects of hypoxia and exercise intervention on night sleep quality of Drosophila melanogaster In Sima-RNAi/+ Drosophila,the nighttime sleep time of D group was significantly higher than that of N group(P<0.01);Hand>Sima RNAi Drosophila,HKd group Drosophila nighttime sleep time,nighttime deep sleep times were significantly higher than Kd group(P<0.01).In Sima-RNAi/+ Drosophila,the number of nighttime sleep and nighttime deep sleep in group E was significantly higher than that in group N(P<0.01).In Hand>Sima RNAi,the number of nighttime deep sleep in EKd group was significantly higher than that in group Kd(P<0.01).In Sima-RNAi/+ Drosophila,the number of nighttime sleep and nighttime deep sleep in HE group was significantly higher than that in N group(P<0.01,P<0.05);Hand>Sima RNAi Drosophila,the number of nighttime sleep and nighttime deep sleep in HEKd group was significantly higher than that in Kd group(P<0.01).3.9 Test results of Drosophila daytime activity under hypoxia and exercise In Sima-RNAi/+Drosophila melanogaster,the number of daily activities and thenumber of activities per minute during daytime awakening in group E were higher than those in group N(P < 0.01,P < 0.05);in group Hand > Sima RNAi,the number of daily activities in group EKd was higher than that in group Kd(P < 0.01).In Sima-RNAi/+Drosophila melanogaster,the number of activities per minute during daytime in HE group was significantly higher than that in N group(P < 0.01,P< 0.05);Hand > Sima RNAi Drosophila melanogaster,the number of activities per minute in HEKd group was significantly higher than that in Kd group(P < 0.01,P < 0.05).4 Conclusion 4.1 Hand>Sima RNAi fruit fly strain was successfully constructed by UAS-Gal4 system.It was found that heart Sima-RNAi/+ and Hand>Sima RNAi Drosophila acute hypoxia led to decreased blood pump function,fibrillation and heart rate in Drosophila heart.The occurrence of irregularities and sleep-wake rhythm disorders.4.2 Hypoxia and regular exercise intervention induced the expression of Sima gene in the heart and participated in the protective effect of Sima-RNAi/+ and Hand>Sima RNAi heart pumping and rhythm function,and improved the acute hypoxia Cardiac dysfunction improves sleep-wake rhythm disorders,improves nighttime sleep quality,and increases daytime activity.4.3 Hypoxic combined exercise intervention is superior to single hypoxic or exercise intervention in improving the heart function and sleep-wake rhythm of SimaRNAi/+ and Hand>Sima RNAi Drosophila,hypoxic exercise can not only improve cardiac function under normal Sima expression,but also improve cardiac Sima gene expression down-regulation of heart function damage in Drosophila.