Cyanidin-3-glucoside(C3G)is the most common anthocyanin in dark grains and berries and is a food functional factor to improve visual health.However,the mechanisms of C3G on blue light-induced retinal pigment epithelia...Cyanidin-3-glucoside(C3G)is the most common anthocyanin in dark grains and berries and is a food functional factor to improve visual health.However,the mechanisms of C3G on blue light-induced retinal pigment epithelial(RPE)cell photooxidative damage needs further exploration.We investigated the effects of C3G on blue light-irradiated A2E-containing RPE cells and explored whether sphingolipid,mitogen-activated protein kinase(MAPK),and mitochondria-mediated pathways are involved in this mechanism.Blue light irradiation led to mitochondria and lysosome damage in RPE cells,whereas C3G preserved mitochondrial morphology and function and maintained the lysosomal integrity.C3G suppressed the phosphorylation of JNK and p38 MAPK and mitochondria-mediated pathways to inhibit RPE cell apoptosis.Lipidomics data showed that C3G protected RPE cells against blue light-induced lipid peroxidation and apoptosis by maintaining sphingolipids balance.C3G significantly inhibited ceramide(Cer d18:0/15:0,Cer d18:0/16:0 and Cer d18:0/18:0)accumulation and elevated galactosylceramide(GalCer d18:1/15:0 and GalCer d18:1/16:0)levels in the irradiated A2E-containing RPE cells.Furthermore,C3G attenuated cell membrane damage by increasing phosphatidylcholine and phosphatidylserine levels.C3G inhibited apoptosis and preserved the structure of mitochondria and lysosome by regulating sphingolipid signaling and suppression of MAPK activation in RPE cells.Thus,dietary supplementation of C3G prevents retinal photooxidative damage.展开更多
Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Antho...Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Anthocyanic Vacuolar Inclusions (AVIs). Using Arabidopsis seedlings grown under anthocyanin-inductive conditions as a model to un- derstand how AVIs are formed, we show here that the accumulation of AVIs strongly correlates with the formation of cyanidin 3-glucoside (C3G) and derivatives. Arabidopsis mutants that fail to glycosylate anthocyanidins at the 5-0 position (Sgt mutant) accumulate AVIs in almost every epidermal cell of the cotyledons, as compared to wild-type seedlings, where only a small fraction of the cells show AVIs. A similar phenomenon is observed when seedlings are treated with vanadate. Highlighting a role for autophagy in the formation of the AVIs, we show that various mutants that interfere with the autophagic process (atg mutants) display lower numbers of AVIs, in addition to a reduced accumulation of anthocyanins. Interestingly, vanadate increases the numbers of AVIs in the atg mutants, suggesting that several pathways might participate in AVl formation. Taken together, our results suggest novel mechanisms for the formation of sub-vacuolar compartments capable of accumulating anthocyanin pigments.展开更多
基金funded by the National Natural Science Foundation of China(31901698)Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(2019QNRC001)。
文摘Cyanidin-3-glucoside(C3G)is the most common anthocyanin in dark grains and berries and is a food functional factor to improve visual health.However,the mechanisms of C3G on blue light-induced retinal pigment epithelial(RPE)cell photooxidative damage needs further exploration.We investigated the effects of C3G on blue light-irradiated A2E-containing RPE cells and explored whether sphingolipid,mitogen-activated protein kinase(MAPK),and mitochondria-mediated pathways are involved in this mechanism.Blue light irradiation led to mitochondria and lysosome damage in RPE cells,whereas C3G preserved mitochondrial morphology and function and maintained the lysosomal integrity.C3G suppressed the phosphorylation of JNK and p38 MAPK and mitochondria-mediated pathways to inhibit RPE cell apoptosis.Lipidomics data showed that C3G protected RPE cells against blue light-induced lipid peroxidation and apoptosis by maintaining sphingolipids balance.C3G significantly inhibited ceramide(Cer d18:0/15:0,Cer d18:0/16:0 and Cer d18:0/18:0)accumulation and elevated galactosylceramide(GalCer d18:1/15:0 and GalCer d18:1/16:0)levels in the irradiated A2E-containing RPE cells.Furthermore,C3G attenuated cell membrane damage by increasing phosphatidylcholine and phosphatidylserine levels.C3G inhibited apoptosis and preserved the structure of mitochondria and lysosome by regulating sphingolipid signaling and suppression of MAPK activation in RPE cells.Thus,dietary supplementation of C3G prevents retinal photooxidative damage.
文摘Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Anthocyanic Vacuolar Inclusions (AVIs). Using Arabidopsis seedlings grown under anthocyanin-inductive conditions as a model to un- derstand how AVIs are formed, we show here that the accumulation of AVIs strongly correlates with the formation of cyanidin 3-glucoside (C3G) and derivatives. Arabidopsis mutants that fail to glycosylate anthocyanidins at the 5-0 position (Sgt mutant) accumulate AVIs in almost every epidermal cell of the cotyledons, as compared to wild-type seedlings, where only a small fraction of the cells show AVIs. A similar phenomenon is observed when seedlings are treated with vanadate. Highlighting a role for autophagy in the formation of the AVIs, we show that various mutants that interfere with the autophagic process (atg mutants) display lower numbers of AVIs, in addition to a reduced accumulation of anthocyanins. Interestingly, vanadate increases the numbers of AVIs in the atg mutants, suggesting that several pathways might participate in AVl formation. Taken together, our results suggest novel mechanisms for the formation of sub-vacuolar compartments capable of accumulating anthocyanin pigments.