Oxidative stress due to hyperglycemia damages the functions of retinal pigment epithelial (RPE) cells and is a major risk factor for diabetic retinopathy (DR). Paeoniflorin is a monoterpenoid glycoside found in the roots of Paeonia lactiflora Pall and has been reported to have a variety of health benefits. However, the mechanisms underlying its therapeutic effects on high glucose (HG)-induced oxidative damage in RPE cells are not fully understood. In this study, we investigated the protective effect of paeoniflorin against HG-induced oxidative damage in cultured human RPE ARPE-19 cells, an in vitro model of hyperglycemia. Pretreatment with paeoniflorin markedly reduced HG-induced cytotoxicity and DNA damage. Paeoniflorin inhibited HG-induced apoptosis by suppressing activation of the caspase cascade, and this suppression was associated with the blockade of cytochrome c release to cytoplasm by maintaining mitochondrial membrane stability. In addition, paeoniflorin suppressed the HG-induced production of reactive oxygen species (ROS), increased the phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), a key redox regulator, and the expression of its downstream factor heme oxygenase-1 (HO-1). On the other hand, zinc protoporphyrin (ZnPP), an inhibitor of HO-1, abolished the protective effect of paeoniflorin against ROS production in HG-treated cells. Furthermore, ZnPP reversed the protective effects of paeoniflorin against HG-induced cellular damage and induced mitochondrial damage, DNA injury, and apoptosis in paeoniflorin-treated cells. These results suggest that paeoniflorin protects RPE cells from HG-mediated oxidative stress-induced cytotoxicity by activating Nrf2/HO-1 signaling and highlight the potential therapeutic use of paeoniflorin to improve the symptoms of DR.

Cynaropicrin, a sesquiterpene lactone found in artichoke leaves exerts diverse pharmacological effects. This study investigated whether cynaropicrin has a paraptosis-like cell death effect in human hepatocellular carcinoma Hep3B cells in addition to the apoptotic effects reported in several cancer cell lines. Cynaropicrin-induced cytotoxicity and cytoplasmic vacuolation, a key characteristic of paraptosis, were not ameliorated by inhibitors of necroptosis, autophagy, or pan caspase inhibitors in Hep3B cells. Our study showed that cynaropicrin-induced cytotoxicity was accompanied by mitochondrial dysfunction and endoplasmic reticulum stress along with increased cellular calcium ion levels. These effects were significantly mitigated by endoplasmic reticulum stress inhibitor or protein synthesis inhibitor. Moreover, cynaropicrin treatment in Hep3B cells increased reactive oxygen species generation and downregulated apoptosis-linked gene 2-interacting protein X (Alix), a protein that inhibits paraptosis. The addition of the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) neutralized cynaropicrin-induced changes in Alix expression and endoplasmic reticulum stress marker proteins counteracting endoplasmic reticulum stress and mitochondrial impairment. This demonstrates a close relationship between endoplasmic reticulum stress and reactive oxygen species generation. Additionally, cynaropicrin activated p38 mitogen activated protein kinase and a selective p38 mitogen activated protein kinase blocker alleviated the biological phenomena induced by cynaropicrin. NAC pretreatment showed the best reversal of cynaropicrin induced vacuolation and cellular inactivity. Our findings suggest that cynaropicrin induced oxidative stress in Hep3B cells contributes to paraptotic events including endoplasmic reticulum stress and mitochondrial damage.

Oxidative stress due to hyperglycemia damages the functions of retinal pigment epithelial (RPE) cells and is a major risk factor for diabetic retinopathy (DR). Paeoniflorin is a monoterpenoid glycoside found in the roots of Paeonia lactiflora Pall and has been reported to have a variety of health benefits. However, the mechanisms underlying its therapeutic effects on high glucose (HG)-induced oxidative damage in RPE cells are not fully understood. In this study, we investigated the protective effect of paeoniflorin against HG-induced oxidative damage in cultured human RPE ARPE-19 cells, an in vitro model of hyperglycemia. Pretreatment with paeoniflorin markedly reduced HG-induced cytotoxicity and DNA damage. Paeoniflorin inhibited HG-induced apoptosis by suppressing activation of the caspase cascade, and this suppression was associated with the blockade of cytochrome c release to cytoplasm by maintaining mitochondrial membrane stability. In addition, paeoniflorin suppressed the HG-induced production of reactive oxygen species (ROS), increased the phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), a key redox regulator, and the expression of its downstream factor heme oxygenase-1 (HO-1). On the other hand, zinc protoporphyrin (ZnPP), an inhibitor of HO-1, abolished the protective effect of paeoniflorin against ROS production in HG-treated cells. Furthermore, ZnPP reversed the protective effects of paeoniflorin against HG-induced cellular damage and induced mitochondrial damage, DNA injury, and apoptosis in paeoniflorin-treated cells. These results suggest that paeoniflorin protects RPE cells from HG-mediated oxidative stress-induced cytotoxicity by activating Nrf2/HO-1 signaling and highlight the potential therapeutic use of paeoniflorin to improve the symptoms of DR.

Cynaropicrin, a sesquiterpene lactone found in artichoke leaves exerts diverse pharmacological effects. This study investigated whether cynaropicrin has a paraptosis-like cell death effect in human hepatocellular carcinoma Hep3B cells in addition to the apoptotic effects reported in several cancer cell lines. Cynaropicrin-induced cytotoxicity and cytoplasmic vacuolation, a key characteristic of paraptosis, were not ameliorated by inhibitors of necroptosis, autophagy, or pan caspase inhibitors in Hep3B cells. Our study showed that cynaropicrin-induced cytotoxicity was accompanied by mitochondrial dysfunction and endoplasmic reticulum stress along with increased cellular calcium ion levels. These effects were significantly mitigated by endoplasmic reticulum stress inhibitor or protein synthesis inhibitor. Moreover, cynaropicrin treatment in Hep3B cells increased reactive oxygen species generation and downregulated apoptosis-linked gene 2-interacting protein X (Alix), a protein that inhibits paraptosis. The addition of the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) neutralized cynaropicrin-induced changes in Alix expression and endoplasmic reticulum stress marker proteins counteracting endoplasmic reticulum stress and mitochondrial impairment. This demonstrates a close relationship between endoplasmic reticulum stress and reactive oxygen species generation. Additionally, cynaropicrin activated p38 mitogen activated protein kinase and a selective p38 mitogen activated protein kinase blocker alleviated the biological phenomena induced by cynaropicrin. NAC pretreatment showed the best reversal of cynaropicrin induced vacuolation and cellular inactivity. Our findings suggest that cynaropicrin induced oxidative stress in Hep3B cells contributes to paraptotic events including endoplasmic reticulum stress and mitochondrial damage.

Oxidative stress due to hyperglycemia damages the functions of retinal pigment epithelial (RPE) cells and is a major risk factor for diabetic retinopathy (DR). Paeoniflorin is a monoterpenoid glycoside found in the roots of Paeonia lactiflora Pall and has been reported to have a variety of health benefits. However, the mechanisms underlying its therapeutic effects on high glucose (HG)-induced oxidative damage in RPE cells are not fully understood. In this study, we investigated the protective effect of paeoniflorin against HG-induced oxidative damage in cultured human RPE ARPE-19 cells, an in vitro model of hyperglycemia. Pretreatment with paeoniflorin markedly reduced HG-induced cytotoxicity and DNA damage. Paeoniflorin inhibited HG-induced apoptosis by suppressing activation of the caspase cascade, and this suppression was associated with the blockade of cytochrome c release to cytoplasm by maintaining mitochondrial membrane stability. In addition, paeoniflorin suppressed the HG-induced production of reactive oxygen species (ROS), increased the phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), a key redox regulator, and the expression of its downstream factor heme oxygenase-1 (HO-1). On the other hand, zinc protoporphyrin (ZnPP), an inhibitor of HO-1, abolished the protective effect of paeoniflorin against ROS production in HG-treated cells. Furthermore, ZnPP reversed the protective effects of paeoniflorin against HG-induced cellular damage and induced mitochondrial damage, DNA injury, and apoptosis in paeoniflorin-treated cells. These results suggest that paeoniflorin protects RPE cells from HG-mediated oxidative stress-induced cytotoxicity by activating Nrf2/HO-1 signaling and highlight the potential therapeutic use of paeoniflorin to improve the symptoms of DR.

Cynaropicrin, a sesquiterpene lactone found in artichoke leaves exerts diverse pharmacological effects. This study investigated whether cynaropicrin has a paraptosis-like cell death effect in human hepatocellular carcinoma Hep3B cells in addition to the apoptotic effects reported in several cancer cell lines. Cynaropicrin-induced cytotoxicity and cytoplasmic vacuolation, a key characteristic of paraptosis, were not ameliorated by inhibitors of necroptosis, autophagy, or pan caspase inhibitors in Hep3B cells. Our study showed that cynaropicrin-induced cytotoxicity was accompanied by mitochondrial dysfunction and endoplasmic reticulum stress along with increased cellular calcium ion levels. These effects were significantly mitigated by endoplasmic reticulum stress inhibitor or protein synthesis inhibitor. Moreover, cynaropicrin treatment in Hep3B cells increased reactive oxygen species generation and downregulated apoptosis-linked gene 2-interacting protein X (Alix), a protein that inhibits paraptosis. The addition of the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) neutralized cynaropicrin-induced changes in Alix expression and endoplasmic reticulum stress marker proteins counteracting endoplasmic reticulum stress and mitochondrial impairment. This demonstrates a close relationship between endoplasmic reticulum stress and reactive oxygen species generation. Additionally, cynaropicrin activated p38 mitogen activated protein kinase and a selective p38 mitogen activated protein kinase blocker alleviated the biological phenomena induced by cynaropicrin. NAC pretreatment showed the best reversal of cynaropicrin induced vacuolation and cellular inactivity. Our findings suggest that cynaropicrin induced oxidative stress in Hep3B cells contributes to paraptotic events including endoplasmic reticulum stress and mitochondrial damage.

Purpose: Research comparing and evaluating the properties of various dental materials is an important topic in the field of dentistry. This study aims to evaluate the fluoride release and microhardness properties of various fluoride-containing restorative materials used in dental treatments. Materials and Methods: Thirty specimens of four restorative materials were pre-pared (5 mm × 2 mm, cylindrical): alkasite-based material (Cention N, CN), Self-cure glass Ionomer (Riva self cure, RS), Resin-modified glass ionomer cement (Fuji LC II, FL) and composite resin (Filtek Z350XT, FZ). Fluoride release measurements were conducted on 25 specimens at intervals of 1, 2, 6, 13, 20, and 27 days with a fluoride electrode connected to the pH/ISE Meter (Orion Star A214, Thermo Scientific, USA) and cumulative fluoride release was calculated. Vickers microhardness measurements were performed on five specimens from each material with microhardness tester (DM2D, AFFRI, Italy). Results: As a result of measuring the amount of fluoride release over 27 days, the amount of fluoride release in CN showed a gradual increase, while the amount of fluoride release in RS, FL, and FZ gradually decreased. The cumulative fluoride release amount for 28 days was significantly higher in CN and FL than in RS (P < 0.05). FZ and RS demonstrated significantly higher microhardness compared to CN and FL (P < 0.05). FZ and RS showed similar microhardness, and FL showed the lowest microhardness. Conclusion Cention N (CN) exhibited superior fluoride release compared to Glass Ionomer Cement (RS), making it a promising option for preventing secondary caries. However, it displayed a lower microhardness than the composite resin (FZ), indicating potential limitations in terms of mechanical strength. Therefore, if an anti-caries action is required, Cention N may be considered first; however, it appears to be difficult to use in posterior permanent teeth.