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.

Objective: In this study, changes in treatment methods and patient prognosis were analyzed using a Korean nationwide medical insurance information database. Methods: Patients with subarachnoid hemorrhage who received surgical treatment for cerebral aneurysm from 2005 to 2020 were included. The specific surgery type was classified using the surgical code and according to whether stents were used. Yearly trends in mortality rates and poor prognosis, using tracheostomy as proxy, were analyzed by a simple regression analysis. A multistep logistic regression analysis was performed to evaluate the risk factors of mortality and poor prognosis. Results: Overall, 83,587 patients were included. Females were predominant (64.5%). Microsurgical clip usage rate decreased by approximately two-thirds from 78.8% in 2005 to 24.4% in 2020. Contrarily, endovascular treatment proportion gradually increased, and stent-assisted coil embolization rate surpassed microsurgical clip usage rate in 2020 (24.6% vs. 24.4%). In the multivariate analysis, endovascular treatment correlated positively with 3-month mortality (hazard ratio [HR]: 1.13, 95% confidence interval [CI]: 1.07–1.19, P<0.0001), although correlated negatively with poor prognosis (tracheostomy) (HR: 0.93, 95% CI: 0.89–0.98, P=0.0050). Conclusions According to the treatment trend analysis, during the 16 years studied, for patients with subarachnoid hemorrhage due to ruptured cerebral aneurysm, the endovascular treatment rate increased rapidly and stent-assisted coil embolization rate surpassed that of microsurgical clip ligation. Diversification of treatment methods has led to a decrease in mortality and improved prognosis.

Purpose: Claudin 18.2 (CLDN18.2) has emerged as a promising therapeutic target for CLDN18.2-expressing gastric cancer (GC). We sought to examine the heterogeneity of CLDN18.2 expression between primary GC (PGC) and metastatic GC (MGC) using various scoring methods. Materials and Methods: We retrospectively analyzed data from 102 patients with pathologically confirmed paired primary and metastatic gastric or gastroesophageal junction adenocarcinomas. CLDN18.2 expression was evaluated through immunohistochemistry on formalin-fixed paraffin-embedded tissue samples. We assessed CLDN18.2 positivity using multiple scoring approaches, including the immunoreactivity score, H-score, and the percentage of tumor cells showing moderate-to-strong staining intensity. We analyzed the concordance rates between PGC and MGC and the association of CLDN18.2 positivity with clinicopathological features. Results: CLDN18.2 positivity varied from 25% to 65% depending on the scoring method, with PGC consistently showing higher expression levels than MGC. Intratumoral heterogeneity was noted in 25.5% of PGCs and 19.6% of MGCs. Intertumoral heterogeneity, manifesting as discordance in CLDN18.2 positivity between PGC and MGC, was observed in about 20% of cases, with moderate agreement across scoring methods (κ=0.47 to 0.60).In PGC, higher CLDN18.2 positivity correlated with synchronous metastasis, presence of peritoneal metastasis, poorly differentiated grade, and biopsy specimens. In MGC, positivity was associated with synchronous metastasis, presence of peritoneal metastasis, and metastatic peritoneal tissues. Conclusions CLDN18.2 expression demonstrates significant heterogeneity between PGC and MGC, with a 20% discordance rate. Comprehensive tissue sampling and reassessment of CLDN18.2 status are crucial, especially before initiating CLDN18.2-targeted therapies.

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.