Department of Veterinary Medical Sciences, University of Bologna, 40064 Ozzano Emilia, Italy.
Department of Health Sciences, Institute of Research for Food Safety & Health (IRC-FSH), University Magna Graecia of Catanzaro, 88100 Catanzaro, Italy.
Cells. 2022 Apr 20;11(9):1401. doi: 10.3390/cells11091401.
The bergamot polyphenolic fraction (BPF) was evaluated in the FF-ATPase activity of swine heart mitochondria. In the presence of a concentration higher than 50 µg/mL BPF, the ATPase activity of FF-ATPase, dependent on the natural cofactor Mg, increased by 15%, whereas the enzyme activity in the presence of Ca was inhibited by 10%. By considering this opposite BPF effect, the FF-ATPase activity involved in providing ATP synthesis in oxidative phosphorylation and triggering mitochondrial permeability transition pore (mPTP) formation has been evaluated. The BPF improved the catalytic coupling of oxidative phosphorylation in the presence of a substrate at the first phosphorylation site, boosting the respiratory control ratios (state 3/state 4) by 25% and 85% with 50 µg/mL and 100 µg/mL BPF, respectively. Conversely, the substrate at the second phosphorylation site led to the improvement of the state 3/state 4 ratios by 15% only with 100 µg/mL BPF. Moreover, the BPF carried out its beneficial effect on the mPTP phenomenon by desensitizing the pore opening. The acute effect of the BPF on the metabolism of porcine aortica endothelial cells (pAECs) showed an ATP rate index greater than one, which points out a prevailing mitochondrial oxidative metabolism with respect to the glycolytic pathway, and this ratio rose by about three times with 100 µg/mL BPF. Consistently, the mitochondrial ATP turnover, in addition to the basal and maximal respiration, were higher in the presence of the BPF than in the controls, and the MTT test revealed an increase in cell viability with a BPF concentration above 200 µg/mL. Therefore, the molecule mixture of the BPF aims to ensure good performance of the mitochondrial bioenergetic parameters.
香柠檬多酚部分（BPF）在猪心肌线粒体 FF-ATP 酶活性中进行了评估。在 BPF 浓度高于 50μg/mL 的情况下，依赖于天然辅因子 Mg 的 FF-ATP 酶的 ATP 酶活性增加了 15%，而在存在 Ca 的情况下，酶活性则被抑制了 10%。考虑到 BPF 的这种相反作用，评估了参与提供氧化磷酸化中 ATP 合成并触发线粒体通透性转换孔（mPTP）形成的 FF-ATP 酶活性。BPF 改善了在第一磷酸化部位存在底物的情况下氧化磷酸化的催化偶联，分别使呼吸控制比（状态 3/状态 4）提高了 25%和 85%，BPF 的浓度为 50μg/mL 和 100μg/mL。相反，仅用 100μg/mL BPF 可使第二磷酸化部位的底物使状态 3/状态 4 比值提高 15%。此外，BPF 通过使孔开放脱敏来发挥其对 mPTP 现象的有益作用。BPF 对猪主动脉内皮细胞（pAECs）代谢的急性作用显示 ATP 速率指数大于 1，这表明与糖酵解途径相比，存在占主导地位的线粒体氧化代谢，并且该比值在 100μg/mL BPF 存在下上升约三倍。一致地，与对照相比，BPF 存在时线粒体 ATP 周转率、基础呼吸和最大呼吸均较高，MTT 试验显示随着 BPF 浓度高于 200μg/mL，细胞活力增加。因此，BPF 的分子混合物旨在确保线粒体生物能量学参数的良好性能。
