本研究目的為探討長期補充不同劑量之達瑪烷次苷 (dammarane oligo-sapogenins, DS)對單次耗竭性運動後大鼠骨骼肌自噬作用之影響。將32隻Sprague-Dawley (SD)大鼠依體重配對方式分為4組:控制組、DS20、DS60與DS120組,並以餵管方式分別餵食不同劑量之達瑪烷次苷10週,在第10週給予單次的耗竭性運動後立即犧牲,採集之骨骼肌樣本作為評估自噬作用相關指標蛋白表現量。研究結果顯示經過10週不同劑量之達瑪烷次苷介入,並給予單次耗竭性運動挑戰後,DS20、DS60與DS120三組之股四頭白肌BCL-2蛋白表現量及磷酸化程度明顯高於控制組,但三組補充組間則無明顯差異。四組股四頭紅白肌之caspase-3、beclin-1及p62蛋白表現在單次耗竭性運動後皆無明顯差異。本研究結論:10週不同劑量(DS20、DS60與DS120)之達瑪烷次苷補充,在單次耗竭性運動後明顯提高大鼠股四頭白肌之BCL-2蛋白表現及磷酸化程度,但此提升之效果無劑量依存效應。另外,四組自噬作用相關調節蛋白caspase-3、beclin-1及p62表現量則無明顯差異。根據以上結果顯示長期補充達瑪烷次苷在單次耗竭運動後似乎無法有效提高骨骼肌細胞自噬作用。
The purpose of this study was to investigate the effect of dammarane oligo-sapogenins (DS) supplementation on muscle autophagy following a single bout of exhaustive exercise in rats. Thirty-two Sprague-Dawley rats were weight-matched and divided into four groups, including control (vehicle), DS20 (20 mg/kg), DS60 (60 mg/kg) and DS120 (120 mg/kg). All rats were orally gavaged with respective doses of DS for 10 weeks. Immediately after acute exhaustive swimming exercise, the rats were sacrificed, and the quadriceps muscle samples were collected for determining the autophagy related biomarkers. The results indicated that the BCL-2 protein expression and BCL-2 phosphorylation were significantly increased with three different doses of DS following a single bout of exhaustive swimming exercise in white quadriceps muscle. However, there was no difference among all groups with DS treatment. The relative protein expressions of caspase-3, beclin-1 and p62 were not significantly different between the groups after intervention. We conclude that ten-week DS supplementation markedly increased the BCL-2 protein and phosphorylation levels in white quadriceps muscle, whereas no dose response pattern was observed. In addition, there were no significant differences in protein expressions of caspase-3, beclin-1 and p62 among all groups. These results suggest that long-term DS supplementation might not effectively elevate the muscle cell autophagy after a single bout of exercise.