Mechanism on Banxia Xiexintang Inducing Ferroptosis in Gastric Cancer Cells Based on Nrf2/GPX4 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of Banxia Xiexintang （BXT） on the proliferation of human gastric cancer HGC-27， MKN-45， and AGS cells and its mechanism. MethodCell counting kit-8 （CCK-8） was used to detect the effects of different concentrations of BXT-containing serum （5%， 10%， and 20%） on the proliferation of HGC-27， MKN-45， and AGS cells. A mitochondrial membrane potential probe （TMRE） was used to detect the expression of mitochondrial membrane potential in cells. A kit was used to detect iron ion （Fe2+） content， lipid peroxide （LPO）， and superoxide dismutase （SOD） activity. Western blot was used to detect the protein expression levels of glycogen synthase3β （GSK3β）， phosphorylated GSK3β （p-GSK3β）， nuclear factor E2 related factor 2 （Nrf2）， and glutathione peroxidase 4 （GPX4）. The real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of member 11 of the cystine/glutamic acid reverse transporter solute vector family 7 （SLC7A11）， member 2 of the heavy chain solute vector family 3 （SLC3A2）， transferrin receptor 3 （TFRC）， and tumor protein （TP）53. ResultCCK-8 results showed that BXT and capecitabine could significantly reduce the survival rate of three kinds of gastric cancer cells after treatment with drug-containing serum for 24 h （P<0.01）. After 48 h of intervention with drug-containing serum， the survival rate of three kinds of gastric cancer cells was significantly decreased in both the capecitabine group and the BXT group compared with the blank group. The BXT group was dose-dependent， with 20% BXT having the most significant effect （P<0.01）. In terms of biochemical indicators of ferroptosis， compared with the blank group， BXT and capecitabine significantly decreased the expression of mitochondrial membrane potential （P<0.01） and SOD activity （P<0.01） and significantly increased the contents of LPO and Fe2+ （P<0.01）， so as to improve the sensitivity of gastric cancer cells to ferroptosis. In terms of the Nrf2/GPX4 pathway， compared with the blank group， the BXT group could reduce the protein expressions of p-GSK3β， Nrf2， and GPX4 （P<0.01） in gastric cancer cells and increase mRNA expressions of SLC7A11 and SLC3A2 （P<0.05）. It could also increase the protein expression of GSK3β （P<0.01） and mRNA expression of TP53 and TFRC （P<0.05， P<0.01） in gastric cancer cells. Inhibition of the Nrf2/GPX4 pathway induces ferroptosis in gastric cancer cells. Compared with the capecitabine group， the 20% BXT group showed a more obvious effect. ConclusionBanxia Xiexintang can induce ferroptosis in gastric cancer cells HGC-27， MKN-45， and AGS by inhibiting the Nrf2/GPX4 pathway.

Role and mechanism of action of Yinchenhao Decoction in inhibiting ferroptosis of hepatocytes in mice with autoimmune hepatitis / 临床肝胆病杂志

ObjectiveTo investigate the role and mechanism of action of Yinchenhao Decoction in inhibiting ferroptosis of hepatocytes in mice with autoimmune hepatitis. MethodsA total of 18 specific pathogen-free female C57BL/6 mice were selected and divided into normal group， model group， and treatment group using a random number table， with 6 mice in each group. The mice in the model group and the treatment group were injected with concanavalin A （Con A） via the caudal vein to establish a mouse model of autoimmune hepatitis， and those in the normal group were injected with normal saline. The mice in the treatment group were given prophylactic treatment with Yinchenhao Decoction （4.68 g crude drug/kg） by gavage at 14 days before modeling， and Con A was injected after the last gavage. The levels of alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， interferon gamma （IFN-γ）， tumor necrosis factor-α （TNF-α）， iron ion， glutathione （GSH）， reactive oxygen species （ROS）， adenosine triphosphate （ATP）， and malondialdehyde （MDA） were measured； liver index and spleen index were calculated； the expression levels of GPX4 and SLC7A11 were measured； liver histopathological changes were compared between groups. A one-way analysis of variance was used for comparison of normally distributed continuous data between three groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the normal group， the model group had significant increases in liver index， spleen index， ALT， AST， IFN-γ， TNF-α， iron ion， ROS and MDA （all P<0.05） and significant reductions in the content of GSH and ATP and the protein expression levels of GPX4 and SLC7A11 （all P<0.05）. Compared with the model group， the treatment group had significant reductions in liver index， spleen index， ALT， AST， IFN-γ， TNF-α， iron ion， ROS and MDA （all P<0.05） and significant increases in the content of GSH and ATP and the protein expression levels of GPX4 and SLC7A11 （all P<0.05）. HE staining showed that compared with the normal group， the model group showed massive hepatocyte degeneration and necrosis and inflammatory cell aggregation at the portal area， and compared with the model group， the treatment group had alleviation of liver necrosis and inflammatory infiltration. ConclusionLiver injury induced by Con A may be associated with ferroptosis. Yinchenhao Decoction can increase the protein expression levels of SLC7A11 and GPX4 protein and thus inhibit ferroptosis of hepatocytes induced by Con A.

Impact of antioxidant therapy on antioxidant capacity in hypertensive patients

Background: Hypertension is consistently related to the development of ischemic heart disease, heart failure, stroke, and chronic kidney disease. Oxidative stress has been associated with mechanisms of hypertension which could be nullified by antioxidants such as Vitamin C and Vitamin E. Aim and Objectives: The objectives of the study are as follows: (i) To estimate the impact of antioxidant therapy on antioxidant capacity in hypertensive patients; (ii) to measure serum levels of glutathione, glutathione peroxidase (GPx), glutathione reductase (GR), and superoxide dismutase (SOD) in hypertensive patients before and after giving them antioxidant therapy for 45 days. Materials and Methods: Thirty randomly selected hypertensive patients were given Supradyn tablet once a day for 45 days. Ferric reducing ability of plasma (FRAP), SOD, GR, GPx, and reduced Glutathione assays were measured before and after the intervention therapy. Results: Total antioxidant capacity as measured by serum FRAP in hypertensive patients before and after the therapy was increased significantly from 578.8 ± 60.85 to 592.1 ± 59.66 (?mol/L), respectively. The levels of SOD, GPx, GR, and Glutathione in hypertensive patients before giving antioxidant therapy were 1.6 ± 0.49 U/ml, 184.6 ± 17.1 ?mol/L/min, 8.96 ± 1.15 ?mol/L/min, and 8.03 ± 0.96 ?mol/g of Hb, respectively. The same after giving them antioxidant therapy were 1.7 ± 0.46 U/ml, 182.4 ± 15.98 ?mol/L/min, 8.83 ± 1.11 ?mol/L/min, and 7.83 ± 0.94 ?mol/g of Hb, respectively. The levels of GPx, GR, and Glutathione were significantly decreased after giving antioxidant therapy for 45 days while SOD level did not change significantly. Conclusion: Antioxidant therapies for 45 days led to a significant increase in total antioxidant capacity as shown by plasma FRAP levels and a significant decrease in serum levels of enzymatic antioxidants such as GPx, GR and Glutathione in hypertensive patients. However, serum levels of SOD did not show a significant change.

Influence of glutathione-related genetic variants on the oxidative stress profile of Mexican patients with psychotic disorders

Objective: The clinical trajectories of patients with psychotic disorders have divergent outcomes, which may result in part from glutathione (GSH)-related high-risk genotypes. We aimed to determine pharmacokinetics of clozapine, GSH levels, GSH peroxidase (GPx) activity, gene variants involved in the synthesis and metabolism of GSH, and their association with psychotic disorders in Mexican patients on clozapine monotherapy and controls. Methods: The sample included 75 patients with psychotic disorders on clozapine therapy and 40 paired healthy controls. Plasma clozapine/N-desmethylclozapine, GSH concentrations, and GPx activity were determined, along with genotyping of GCLC and GSTP1 variants and copy number variations of GSTP1, GSTT1, and GSTM1. Clinical, molecular and biochemical data were analyzed with a logistic regression model. Results: GSH levels were significantly reduced and, conversely, GPx activity was higher among patients than controls. GCLC_GAG-7/9 genotype (OR = 4.3, 95%CI = 1.40-14.31, p = 0.019) and hetero-/homozygous genotypes of GCLC_rs761142 (OR = 6.09, 95%CI = 1.93-22.59, p = 0.003) were found to be risk factors for psychosis. The genetic variants were not related to clozapine/N-desmethylclozapine levels or metabolic ratio. Conclusions: GCLC variants were associated with the oxidative stress profile of patients with psychotic disorders, raising opportunities for intervention to improve their antioxidant defenses. Further studies with larger samples should explore this proposal.

Research progress on the role and mechanism of ferroptosis in renal fibrosis / 中华肾脏病杂志

Ferroptosis is a recently identified type of non-apoptotic cell death, mainly caused by disruption of cellular metabolic pathways such as iron metabolism and reactive oxygen species metabolism, characterized by intracellular iron overload and reactive oxygen species accumulation leading to lipid peroxidation. Ferroptosis is closely related to renal diseases. The role of ferroptosis in diseases such as acute kidney injury and renal cell carcinoma has been extensively studied, and new discoveries and advances have been made in its relationship with renal fibrosis. The paper systematically reviews the relationship between ferroptosis and renal fibrosis in terms of the latest regulatory mechanisms of ferroptosis and its role in renal fibrosis, and explores the potential clinical application of targeted inhibition of ferroptosis to prevent renal fibrosis.

Role of Nrf2/GPX4 signaling pathway-mediated ferroptosis in midazolam-induced reduction of HIBD in neonatal rats / 中华麻醉学杂志

Objective:To evaluate the role of nuclear factor-erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase-4 (GPX4) signaling pathway-mediated ferroptosis in midazolam-induced reduction of hypoxic-ischemic brain damage (HIBD) in neonatal rats.Methods:Ninety healthy 7-day-old neonatal rats, weighing 16-20 g, were divided into 6 groups ( n=15 each) using the random number table method: sham operation group (Sham group), HIBD group, low-dose midazolam (10 mg/kg) group (group L), medium-dose midazolam (20 mg/kg) group (group M), high-dose midazolam (40 mg/kg) group (group H), and Nrf2 inhibitor ML385 group (group I). The HIBD model was developed by ligating the left carotid artery and exposing to a hypoxic condition for 2 h in anesthetized animals. Starting from 2nd day after developing the model, the corresponding doses of midazolam were intraperitoneally injected in midazolam groups, the equal volume of normal saline was intraperitoneally injected in Sham and HIBD groups, midazolam 40 mg/kg and Nrf2 inhibitor ML385 30 mg/kg were intraperitoneally injected once a day for 8 consecutive days in group I. The rats were weighed and subjected to the Morris water maze test after the end of administration. Blood samples were taken from the abdominal aorta after the end of the Morris water maze test, and then the animals were sacrificed to remove the brain for determination of the concentrations of serum iron, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay), contents of iron and GSH in hippocampal tissues (by ultraviolet spectrophotometry and micro method), the number of Nrf2/neuronal nuclear antigen (NeuN) and GPX4/NeuN positive cells (by immunofluorescent staining), and expression of Nrf2, GPX4, and 4-hydroxynonaenoic acid (4-HNE) in hippocampal tissues and for microscopic examination of the pathological changes of hippocampal neurons in brain tissues (after HE staining and Nissl staining). Results:Compared with Sham group, the first time to arrival at platform was significantly prolonged, the number of crossing the origional platform was reduced, and the time of staying at the target quadrant was shortened, the iron content in the hippocampal tissues was increased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were decreased, the expression of Nrf2 and GPX4 was down-regulated, the expression of 4-HNE was up-regulated, the concentrations of serum iron, IL-6 and TNF-α were increased, and the injury to hippocampal neurons was marked in HIBD group ( P<0.05). Compared with HIBD group, the first time to arrival at platform was significantly shortened, the number of crossing the origional platform was increased, and the time of staying at the target quadrant was prolonged, the iron content in the hippocampus tissues was decreased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were increased, the expression of Nrf2 and GPX4 was up-regulated, the expression of 4-HNE was down-regulated, the concentrations of serum iron, IL-6 and TNF-α were decreased ( P<0.05), and the injury to hippocampal neurons was significantly reduced in H, M and L groups. Compared with group H, the first time to arrival at platform was significantly prolonged, the number of crossing the origional platform was reduced, and the time of staying at the target quadrant was shortened, the iron content in the hippocampus tissue was increased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were decreased, the expression of Nrf2 and GPX4 was down-regulated, the expression of 4-HNE was up-regulated, the concentrations of serum iron, IL-6 and TNF-α were increased ( P<0.05), and the injury to hippocampal neurons was aggravated in group I. Conclusions:The mechanism by which midazolam reduces HIBD may be related to activation of the Nrf2/GPX4 signaling pathway and inhibition of hippocampal neuronal ferroptosis in neonatal rats.

Effect of diosmetin on ferroptosis of hippocampal cells in rats with bacterial meningitis and the mechanism of SIRT1-Nrf2 signaling pathway / 中华行为医学与脑科学杂志

Objective:To explore the effect and mechanism of diosmetin (Dio) on neuronal ferroptosis in rats with bacterial meningitis (BM).Methods:Male SD rats aged 6-7 weeks of SPF grade were selected for the experiment. The BM model was established by injecting group B hemolytic streptococcus into the cisterna magna of cerebellum. Sixty BM model rats were successfully modeled and divided into model group, low-dose Dio group, medium-dose Dio group, high-dose Dio group and inhibitor group according to the random number table method, with 12 rats in each group. Another 12 weight-matched rats were taken as the control group.The rats in the low-dose Dio group, medium-dose Dio group, high-dose Dio group and the inhibitor group were intragastrically administered with Dio at 50 mg/kg, 100 mg/kg, 200 mg/kg and 200 mg/kg, respectively. The rats in the control group were intragastrically administered with an equal volume of 0.9 % sodium chloride solution. On the day of intragastric administration, the rats in the inhibitor group were intraperitoneally injected with SIRT1 pathway inhibitor EX527 (10 mg/kg), and the rats in the other groups were injected with an equal volume of 0.9% sodium chloride solution. The above interventions were performed once a day for 28 consecutive days. Loeffler neurological score was used to evaluate the neurological impairment in rats. Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in cerebrospinal fluid of rats were detected by ELISA. The number of white blood cells in cerebrospinal fluid was detected by a blood cell analyzer. Glutathione (GSH) was detected by micro-enzyme labeling method, malondialdehyde (MDA) was detected by thiobarbituric acid colorimetric method, reactive oxygen species(ROS) was detected by colorimetry, and Fe 2+ level was detected by ferrozine method. Hematoxylin-eosin staining, Prussian blue staining and TUNEL staining were used to observe the pathological damage, iron accumulation and apoptosis in the hippocampus, respectively.Western blot was applied to measure the expression of transferrin (Tf), proliferating cell nuclear antigen (PCNA), Bcl-2-associated X protein (Bax), caspase-3 and SIRT1/Nrf2/HO-1/Gpx4 signaling pathway proteins. Graphpad Prism 9.0 was used for data analysis. One-way ANOVA was used for statistical analysis, and SNK- q test was used for further pairwise comparisons. Results:(1) There was a statistically significant difference in neurological function scores among the 6 groups of rats ( F=125.451, P<0.001). The neurological function score of the model group was lower than that of control group, while the neurological function scores of the low-dose Dio group, medium-dose Dio group, and high-dose Dio group were higher than those of the model group (all P<0.05). The neurological function score of the inhibitor group ((2.57±0.26)) was lower than that of high-dose Dio group ((4.34±0.48)) ( P<0.05). (2) There were statistically significant differences in the levels of IL-6, TNF-α and the number of white blood cells in the cerebrospinal fluid of rats among the 6 groups ( F=127.817, 102.413, 180.967, all P<0.001). The levels of IL-6, TNF-α and the number of white blood cells in model group were higher than those of control group(all P<0.05). The levels of IL-6, TNF-α and the number of white blood cells in low-dose Dio group, medium-dose Dio group and high-dose Dio group were lower than those of model group (all P<0.001), and those in inhibitor group were all higher than those in high-dose Dio group(all P<0.001). (3) There were statistically significant differences in iron deposition rate and neuronal apoptosis rate among the 6 groups of rats ( F=90.857, 88.835, both P<0.001). The iron deposition rate ((18.37±3.14)%) and neuronal apoptosis rate ((27.58±2.63)%) in the inhibitor group were higher than those in the high-dose Dio group ((6.35±1.08)%, (14.02±1.87)%) (both P<0.05). (4) The levels of GSH, ROS, MDA, and Fe 2+ in the hippocampus of the 6 groups of rats showed statistically significant differences ( F=54.465, 106.453, 55.969, 105.457, all P<0.001). The GSH content in the inhibitor group ((103.48±8.76) mmol/g) was lower than that in the high-dose Dio group ((133.97±10.54) mmol/g), while the contents of ROS, MDA, Fe 2+ ((225.17±16.32) μmol/mg, (10.73±1.58) μmol/mg, (62.71±5.43) μg/g) were higher than those of the high-dose Dio group ((131.87±11.67) μmol/mg, (4.35±0.87) μmol/mg, (34.86±2.95) μg/g) (all P<0.05). (5)There were statistically significant differences in the protein levels of Tf, PCNA, Bax, caspase-3, SIRT1, Nrf2, HO-1 and Gpx4 in the hippocampus of the 6 groups of rats ( F=120.179, 107.568, 157.265, 98.031, 90.932, 52.283, 59.424, 114.539, all P<0.001). The protein levels of Tf, Bax and caspase-3 in the hippocampus of inhibitor group were higher than those of the high-dose Dio group, while the protein levels of PCNA, SIRT1, Nrf2, HO-1, Gpx4 were lower than those of the high-dose Dio group (all P<0.05). Conclusion:Diosmetin can activate SIRT1/Nrf2/HO-1/Gpx4 signaling pathway, thereby inhibiting neuronal ferroptosis in BM rats.

Effects of neuroendoscopic hematoma removal versus soft channel drainage in the treatment of chronic subdural hematoma / 中国基层医药

Objective:To investigate the clinical efficacy of neuroendoscopic hematoma removal versus soft channel drainage in the treatment of chronic subdural hematoma. Methods:The clinical data of 102 patients with chronic subdural hematoma who received treatment in Jincheng People's Hospital from May 2018 to May 2020 were retrospectively analyzed. They were divided into the neuroendoscopy group ( n = 50) and the soft channel group ( n = 52) according to different surgical methods. Perioperative indexes, hematoma clearance rate, China Stroke Scale score, the activity of daily living score, and oxidative stress indexes were compared between the two groups. All patients were followed up for 3 months. The incidence of complications during the follow-up period was calculated. Results:The retention time of the drainage tube in the neuroendoscopy group was shorter than that in the soft channel group [(2.45 ± 0.63) days vs. (3.30 ± 0.78) days, t = 6.06, P < 0.001]. The length of hospital stay in the neuroendoscopy group was shorter than that in the soft channel group [(7.14 ± 1.65) days vs. (9.07 ± 2.11) days, t = 5.15, P < 0.001]. The hematoma clearance rate at postoperative 7 days in the neuroendoscopy group was higher than that in the soft channel group [(93.45 ± 5.50)% vs. (81.86 ± 7.24)%, χ2 = 9.12, P < 0.001]. There were no significant differences in operation time and intraoperative blood loss between the two groups (both P > 0.05). At postoperative 30 days, the China Stroke Scale score in the neuroendoscopy group was lower than that in the soft channel group [(12.74 ± 2.23) points vs. (18.67 ± 2.45) points, t = 12.79, P < 0.001]. The activity of daily life score in the neuroendoscopy group was significantly higher than that in the soft channel group [(77.69 ± 7.11) points vs. (91.35 ± 7.25) points, t = 9.60, P < 0.001]. At postoperative 7 days, glutathione peroxidase level in the neuroendoscopy group was significantly lower than that in the soft channel group [(130.75 ± 13.66) U/L vs. (148.60 ± 14.64) U/L, t = 6.37, P < 0.001]. Malondialdehyde level in the neuroendoscopy group was significantly lower than that in the soft channel group [(5.11 ± 0.65) nmol/L vs. (6.19 ± 0.74) nmol/L, t = 7.83, P < 0.001]. Superoxide dismutase level in the neuroendoscopy group was significantly higher than that in the soft channel group [(275.60 ± 22.33) U/L vs. (254.60 ± 18.55) U/L, t = 5.15, P < 0.001]. There was no significant difference in the incidence of complications between the two groups ( P > 0.05). Conclusion:Compared with soft channel drainage, neuroendoscopic hematoma removal can obtain better short-term curative effects and less oxidative stress response in the treatment of chronic subdural hematoma. Neuroendoscopic hematoma removal does not increase the incidence of postoperative complications and is highly safe.

Retinal photoreceptor cell damage caused by diabetes through down-regulation of glutathione peroxidase 4 and its mechanism / 中华实验眼科杂志

Objective:To investigate the changes of glutathione peroxidase 4 (GPX4) in retinal photoreceptor cells, and the related mechanism correlated with retinal photoreceptor cell damage.Methods:The posterior segment tissues of 8 age-matched male donors were collected from the Body (Organ) Donation Register and Corneal Receiving Station of Tongji Hospital of Wuhan Red Cross from 2018 to 2021, including 4 non-diabetic donors and 4 diabetic donors.The tissues were divided into diabetes group and control group according to their donors.A total of 14 healthy SPF 8-week-old male C57BL/6 mice were selected and randomly divided into diabetes group and control group by the random number method, with 7 mice in each group.The mice in diabetes group were intraperitoneally injected with streptozotocin at a dose of 50 mg/kg for 5 days, and no intervention was given to mice in control group.Mouse photoreceptor cells 661W were divided into advanced glycation end products (AGEs) group and control group.AGEs group was treated with 100 μg/ml AGEs for 24 hours to simulate diabetic injury, and no intervention was given to control group.The outer segment morphology of retinal photoreceptors in human and mouse retinas was observed by hematoxylin-eosin staining.The expressions of glial fibrillary acidic protein (GFAP), rhodopsin and GPX4 in human and mouse retinas were detected by immunofluorescence staining.The expressions of GFAP, rhodopsin and GPX4 in mouse retina and the expression of GPX4 in 661W cells were determined by Western blot.The activity of 661W cells was detected by cell counting kit-8 (CCK8) method.The concentration of malondialdehyde (MDA) in mouse retina and cells was detected by TBA method.The activity of superoxide dismutase (SOD) in mouse retina and cells was detected by hydroxylamine assay.The use of human tissues was approved by the Ethics Committee of Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology (No.TJ-C20230301). The animal experiments were conducted with reference to the Standards Guide for the Care and Use of Laboratory Animals of the National Institutes of Health, and the study protocol was approved by the Experimental Animal Ethics Committee of Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology (No.TJH-2016001).Results:Hematoxylin-eosin staining showed that retinal photoreceptor outer segments were deformed or broken in diabetic donors and diabetic mice compared with control groups.GFAP fluorescent signal mainly appeared in the inner retina of human and mice, and the stained cells were spindle or polygonal, which was consistent with the shape of glial cells.The retinal GFAP fluorescent signal of diabetic tissue and mouse groups was stronger than that of respective control groups.Rhodopsin was only expressed in the outer segment layer of photoreceptors with clear boundaries, and GPX4 was expressed in the whole retina with strong signal in the outer segment layer of photoreceptors.The fluorescent signals of rhodopsin and GPX4 in diabetic tissue and mouse groups were weaker than those in respective control groups.The relative expressions of GFAP were significantly higher and the relative expressions of rhodopsin and GPX4 were significantly lower in diabetic tissue and mouse groups than in respective control groups (all at P<0.05). The cell viability of AGEs group was significantly lower than that of control group ( t=13.490, P<0.001). The relative expression of GPX4 protein in AGEs group was 0.42±0.12, which was significantly lower than 1.00±0.04 in control group ( t=9.041, P<0.001). MDA concentration was higher and SOD activity was lower in retinal tissue of diabetic mice and AGEs group than those in respective control groups, and the differences were statistically significant (all at P<0.05). Conclusions:Diabetes can reduce the GPX4 level in retinal photoreceptor cells and cause the imbalance of oxidation-antioxidant system, which may be the mechanism of the damage to retinal photoreceptor cells caused by diabetes.

The effect of nuclear factor erythroid 2 related factor 2-induced inhibition of ferroptosis on hyperoxia lung injury / 中华实用儿科临床杂志

Objective:To observe the expression changes of nuclear factor erythroid 2 related factor 2 (Nrf2) and glutathione peroxidase (GPX4) in human pulmonary microvascular endothelial cells (HPMEC) under different experimental conditions, and to explore the role of Nrf2 in inhibiting ferroptosis in the process of alleviating hyperoxic lung injury(HLI).Methods:Hyperoxic model was established by hyperoxia exposure.HPMEC were treated with blank control (control group), oxygen exposure at the concentration of 950 mL/L (hyperoxia group), oxygen exposure at the concentration of 950 mL/L+ 10 μmol/L Ferrostatin (ferroptosis inhibitor group) and oxygen exposure at the concentration of 950 mL/L + 10 μmol/L ML385 (Nrf2 inhibitor group). Cell viability at 24 h and 48 h was tested by the Cell Counting Kit-8 assay, and reactive oxygen species (ROS) levels were detected by a commercial ROS kit.The mRNA and protein levels of Nrf2 and GPX4 were detected by real-time quantitative polymerase chain reaction and Western blot, respectively.Differences were analyzed using the Student′s t-test for a two-group comparison or one-way ANOVA test among groups. Results:(1)Compared with the control group, significantly decreased viability and increased ROS levels were detected in hyperoxia group.Meanwhile, the mRNA (24 h: 0.750±0.010 vs.1.010±0.160, 48 h: 0.690±0.050 vs.1.000±0.070) and protein levels of GPX4 (24 h: 0.160±0.010 vs.0.290±0.010, 48 h: 0.190±0.010 vs.0.250±0.010) at 24 h and 48 h were significantly downregulated, while the mRNA (24 h: 1.740±0.050 vs.1.000±0.050, 48 h: 2.130±0.020 vs.1.000±0.030) and protein levels of Nrf2 (24 h: 0.840±0.010 vs.0.480±0.010, 48 h: 0.840±0.010 vs.0.550±0.030) at 24 h and 48 h were significantly upregulated in hyperoxia group than those of control group (all P<0.05). (2)Compared with the hyperoxia group, significantly increased viability and decreased ROS levels were detected in ferroptosis inhibitor group.Meanwhile, the mRNA (24 h: 1.520±0.110, 48 h: 1.880±0.050) and protein levels of GPX4 (24 h: 0.290±0.010, 48 h: 0.250±0.004) at 24 h and 48 h were significantly upregulated, while the mRNA (24 h: 0.780±0.040, 48 h: 0.760±0.030) and protein levels of Nrf2 (24 h: 0.480±0.010, 48 h: 0.540±0.020) at 24 h and 48 h were significantly downregulated in ferroptosis inhibitor group than those of hyperoxia group (all P<0.05). (3)Compared with the hyperoxia group, significantly decreased viability and increased ROS levels were detected in Nrf2 inhibitor group.Meanwhile, the mRNA (24 h: 0.600±0.030, 48 h: 0.590±0.003) and protein levels of GPX4 (24 h: 0.150±0.001, 48 h: 0.180±0.001) at 24 h and 48 h were significantly downregulated, while the mRNA level of Nrf2 was significantly upregulated at 24 h (3.360±0.130), but downregulated at 48 h (1.430±0.130) (all P<0.05). No significant difference was detected in the protein level of Nrf2 at 24 h and 48 h between hyperoxia group and Nrf2 inhibitor group ( P>0.05). Conclusions:Ferroptosis is involved in the development of HLI, and Nrf2 is able to alleviate hyperoxic lung injury by inhibiting ferroptosis.Therefore, inhibition of ferroptosis by Nrf2 may provide a new therapeutic target for HLI.

Role and prospect of ferroptosis in ischemia-reperfusion injury during organ transplantation / 器官移植

Ferroptosis is a newly-emerged pattern of programmed cell death discovered in recent years, which is defined as iron-dependent programmed necrosis mediated by lipid peroxidation damage. As a conservative procedure, ferroptosis plays a vital role in the development and diseases of multiple organisms including plants and animals. Since ferroptosis was first reported in 2012, growing interests have been diverted to the process of ferroptosis and its role in disease treatment. Ischemia-reperfusion injury is a common pathological process during organ transplantation, and ferroptosis is considered as one of the main patterns inducing ischemia-reperfusion injury. Consequently, the definition, regulatory mechanism and the mechanisms of ferroptosis in ischemia-reperfusion injury after kidney, liver, heart and lung transplantations were reviewed, aiming to provide theoretical basis for the prevention and treatment of ischemia-reperfusion injury in organ transplantation.

Mechanism of blue light-induced ferroptosis in retinal pigment epithelium cells / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the occurrence and possible mechanism of blue light-induced ferroptosis in retinal pigment epithelial cells.METHODS: ARPE-19 cells cultured in vitro were irradiated by 405 nm blue light at 50 mW/cm2 irradiance with different duration and were divided into control, 16.3J/cm2, 32.6J/cm2, and 65.2J/cm2 groups; the 65.2J/cm2 group was defined as the high-level blue light irradiation group and cells were further divided into control, high-level blue light irradiation group and high-level blue light irradiation + ferroptosis inhibitor group. CCK-8 assay was used to detect cell viability, commercial kits were used to detect intracellular glutathione(GSH), ferrous iron and malondialdehyde(MDA)concentration, and Western blot was used to detect the relative expression of glutathione peroxidase 4(GPX4)and xCT proteins in cells.RESULTS: The decrease of ARPE-19 cell viability caused by blue light irradiation was dose-dependent, and the reduction of intracellular GSH concentration, the increase of ferrous iron concentration and MDA concentration were all caused by high-level blue light irradiation(all P&#x0026;#x003C;0.05); the ferroptosis inhibitor partially restored cell viability and recovered intracellular GSH, reduced concentrations of MDA and ferrous iron in the blue light irradiation group(all P&#x0026;#x003C;0.05). The relative expressions of GPX4 and xCT proteins were significantly decreased in the blue light irradiation group, and such change was alleviated by the ferroptosis inhibitor(P&#x0026;#x003C;0.05).CONCLUSION: Blue light irradiation may induce ferroptosis in RPE cells by targeting the xCT and GPX4-associated antioxidant pathways.

Novel perspective in transplantation therapy of mesenchymal stem cells: targeting the ferroptosis pathway / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Ex vivo culture-amplified mesenchymal stem cells (MSCs) have been studied because of their capacity for healing tissue injury. MSC transplantation is a valid approach for promoting the repair of damaged tissues and replacement of lost cells or to safeguard surviving cells, but currently the efficiency of MSC transplantation is constrained by the extensive loss of MSCs during the short post-transplantation period. Hence, strategies to increase the efficacy of MSC treatment are urgently needed. Iron overload, reactive oxygen species deposition, and decreased antioxidant capacity suppress the proliferation and regeneration of MSCs, thereby hastening cell death. Notably, oxidative stress (OS) and deficient antioxidant defense induced by iron overload can result in ferroptosis. Ferroptosis may inhibit cell survival after MSC transplantation, thereby reducing clinical efficacy. In this review, we explore the role of ferroptosis in MSC performance. Given that little research has focused on ferroptosis in transplanted MSCs, further study is urgently needed to enhance the in vivo implantation, function, and duration of MSCs.

In vivo antioxidant activity of rabbiteye blueberry (Vaccinium ashei cv. 'Brightwell') anthocyanin extracts / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Blueberries are rich in phenolic compounds including anthocyanins which are closely related to biological health functions. The purpose of this study was to investigate the antioxidant activity of blueberry anthocyanins extracted from 'Brightwell' rabbiteye blueberries in mice. After one week of adaptation, C57BL/6J healthy male mice were divided into different groups that were administered with 100, 400, or 800 mg/kg blueberry anthocyanin extract (BAE), and sacrificed at different time points (0.1, 0.5, 1, 2, 4, 8, or 12 h). The plasma, eyeball, intestine, liver, and adipose tissues were collected to compare their antioxidant activity, including total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity and glutathione-peroxidase (GSH-PX/GPX) content, and the oxidative stress marker malondialdehyde (MDA) level. The results showed that blueberry anthocyanins had positive concentration-dependent antioxidant activity in vivo. The greater the concentration of BAE, the higher the T-AOC value, but the lower the MDA level. The enzyme activity of SOD, the content of GSH-PX, and messenger RNA (mRNA) levels of Cu,Zn-SOD, Mn-SOD, and GPX all confirmed that BAE played an antioxidant role after digestion in mice by improving their antioxidant defense. The in vivo antioxidant activity of BAE indicated that blueberry anthocyanins could be developed into functional foods or nutraceuticals with the aim of preventing or treating oxidative stress-related diseases.

Resveratrol Attenuates Degeneration and Apoptosis of Cardiomyocytes Induced by Aortic Clamping

ABSTRACT Introduction: Objective: To investigate the potential beneficial effects of resveratrol (RVT) against ischemia-reperfusion injury of myocardial tissue during surgical treatment of ruptured abdominal aortic aneurysm. Methods: Four groups were established — control, ischemia/reperfusion (I/R), sham (I/R+solvent/dimethyl sulfoxide [DMSO]), and I/R+RVT. Ruptured abdominal aortic aneurysm model was used as the experimental protocol. Results: In the I/R and I/R+DMSO groups, malondialdehyde (MDA) levels in myocardial tissue were found to be significantly increased compared to the control group. The MDA level in myocardial tissue was significantly decreased in the I/ R+RVT group compared to the I/R group. In I/R and I/R+DMSO groups, glutathione peroxidase (GSH) levels in myocardial tissue were found to be significantly decreased compared to the control group. The GSH level in the myocardial tissue was significantly increased in the I/R+RVT group compared to the I/R group. In the light microscope, isotropic and anisotropic band disorganized atypical cardiomyocytes in the I/R group and degenerative cardiomyocytes and edematous areas in the I/R+DMSO group were observed. Degenerative cardiomyocytes and edematous areas were decreased in the I/R+RVT group. When heart tissue sections incubated with cleaved caspase-3 primary antibodies were examined under the light microscope, apoptotic cardiomyocytes were present in I/R and I/R+DMSO groups. A decrease in the number of apoptotic cardiomyocytes was observed in the I/R+RVT group. Conclusion: The findings of the present study indicate that RVT exhibits protective effects against ischemia-reperfusion injury occurring in the myocardium as a distant organ as a result of abdominal aorta clamping.

Polyalanine polymorphism in the signal peptide of Glutathione peroxidase 1 (GPX1) gene & its association with osteoporosis

Background & objectives: Osteoporosis is a systemic skeletal disease, characterized by a low bone mass leading to increased bone fragility and hence, a greater susceptibility to the risk of fracture. Since age-related oxidative stress is one of the factors that has been implicated in developing low bone mineral density (BMD), leading to osteoporosis, this study wanted to explore the expression of antioxidant enzymes in individuals with osteoporosis. The present study focused on mapping polymorphism in an important antioxidant enzyme glutathione peroxidase 1 (GPx1) among osteoporosis and healthy Asian Indians. Methods: Dual-energy X-ray absorptiometry was used to assess BMD of individuals and was classified into normal (n=96) and osteoporotic (n=88) groups. Biochemical parameters such as vitamin D, total oxidant status (TOS), and GPx1 enzyme activity were estimated from plasma samples of recruited individuals. Quantitative real-time qRT-PCR was carried out using GAPDH as an endogenous control. Genomic DNA was isolated from whole blood, and polymorphisms were evaluated by sequencing. Results: The BMD was lower in osteoporotic individuals, and further analysis of biochemical parameters indicated significantly low 25-hydroxy vitamin D and GPx1 with higher TOS levels in osteoporotic as compared to healthy individuals. Furthermore, qRT-PCR revealed low expression of GPX1 in osteoporotic individuals. GPX1 sequence analysis of the promoter and two exons revealed the lower frequency of five alanine repeats in the osteoporotic individuals. Interpretation & conclusions: In this study, the in silico analysis revealed the lower frequency of five alanine repeats in exon 1 of GPX1 and high TOS to be associated with osteoporosis. However, no polymorphism was found in exon 2 of GPX1 among the two study groups.

Vitamin D analogues activate vitamin D receptor/glutathione peroxidase 4 pathway to improve ventilator-induced lung injury in mice / 中华危重病急救医学

Objective:To investigate the role of vitamin D analogue paricalcitol in activating vitamin D receptor/glutathione peroxidase 4 (VDR/GPX4) pathway in ventilator-induced lung injury (VILI).Methods:Twenty-four male C57BL/6J mice were randomly divided into control group, high tidal volume (HVT) induced VILI model group (HVT group), paricalcitol control group (P group), and paricalcitol pretreatment group (P+HVT group), with 6 mice in each group. The mice were endotracheal intubated and ventilated at 40 mL/kg tidal volume to prepare VILI model, while those in the control group were intubated without ventilation. The mice in the P+HVT group were intraperitoneally injected with paricalcitol 0.2 μg/kg once a day 1 week before modeling, while those in the P group were intraperitoneally injected paricalcitol 0.2 μg/kg once a day for 1 week before the experiment. After ventilation for 4 hours, the mice were sacrificed for lung tissue collection. Lung injury was evaluated by wet/dry (W/D) ratio, hematoxylin-eosin (HE) staining and Masson staining. The expressions of VDR and GPX4 were determined by Western blotting and immunohistochemistry. Malondialdehyde (MDA) and glutathione (GSH) contents were determined by micro method.Results:After HVT for 4 hours, compared with the control group, lung injury score and W/D ratio were significantly higher (lung injury score: 0.430±0.035 vs. 0.097±0.025, lung W/D ratio: 4.860±0.337 vs. 3.653±0.332, both P < 0.05), collagen fiber deposition was significantly increased, the content of MDA in lung tissue was significantly increased (nmol/g: 212.420±8.757 vs. 97.073±5.308, P < 0.05), GSH content and the protein expressions and immunoreactive score (IRS) of VDR and GPX4 were significantly decreased [GSH (μg/g): 44.229±1.690 vs. 70.840±0.781; VDR protein (VDR/GAPDH): 0.518±0.029 vs. 0.762±0.081, GPX4 protein (GPX4/GAPDH): 0.452±0.032 vs. 0.649±0.034; IRS score: VDR was 4.168±0.408 vs. 10.167±0.408, GPX4 was 4.333±1.033 vs. 10.333±0.516; all P < 0.05], which meant that the mice in HVT group showed obvious lung injury. After VDR was activated by paricalcitol, compared with the HVT group, lung injury score and W/D ratio were significantly decreased (lung injury score: 0.220±0.036 vs. 0.430±0.035, lung W/D ratio: 4.015±0.074 vs. 4.860±0.337, both P < 0.05), collagen fiber deposition was reduced, MDA content in lung tissue was decreased (nmol/g: 123.840±8.082 vs. 212.420±8.757, P < 0.05), GSH content and the protein expressions and IRS score of VDR and GPX4 were significantly up-regulated [GSH (μg/g): 63.094±0.992 vs. 44.229±1.690; VDR protein (VDR/GAPDH): 0.713±0.056 vs. 0.518±0.029, GPX4 protein (GPX4/GAPDH): 0.605±0.008 vs. 0.452±0.032; IRS score: VDR was 9.000±0.632 vs. 4.168±0.408, GPX4 was 8.833±0.408 vs. 4.333±1.033; all P < 0.05], which meant that lung injury in P+HVT group was significantly improved. Conclusion:Vitamin D analogue paricalcitol ameliorates pulmonary oxidation-reduction imbalance by activating the VDR/GPX4 pathway, thereby alleviating VILI.

Ferroptosis: a new target for the treatment of ischemic stroke / 国际脑血管病杂志

Ferroptosis is a new type of programmed cell death that is closely associated with the pathophysiological process of ischemic stroke. Ferroptosis inhibitors can improve neurological function and provide neuroprotection after cerebral ischemia. Therefore, the role of ferroptosis in ischemic stroke and the regulation of ferroptosis to intervene in the occurrence and development of ischemic stroke have become a research hotspot. This article reviews the molecular mechanism and potential therapeutic targets of ferroptosis during ischemic stroke, hoping to provide new perspectives for the treatment of ischemic stroke.

Investigation on myopia of junior high school students in Enshi, Hubei Province with different selenium content / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the myopia of junior high school students in Enshi, Hubei province with different selenium content, and analyze the correlation between the level of serum selenium, hair selenium and myopia.METHODS:A cross-sectional study. A total of 600 students from grades 1-3 of junior high schools(100 students in each grade)in selenium-rich(selenium in soil ≥1.28mg/kg)and selenium-deficient(selenium in soil &#x003C;1.28mg/kg)areas were randomly selected from September 2020 to September 2021, respectively. The level of serum selenium, hair selenium, glutathione peroxidase(GSH-Px)and myopia condition were determined.RESULTS:The serum and hair selenium of myopic group(n=244, 40.7%)were 75.14±11.16μg/L and 0.51±0.01μg/g, respectively. Those in the non-myopic group(n=356, 59.3%)were 110.24±12.14μg/L and 0.68±0.02 μg/g, respectively. The serum selenium and hair selenium in the two groups were different(all P&#x003C;0.01). The serum selenium of 300 students in the selenium-deficient area was 76.74±11.25μg/L, the hair selenium was 0.45±0.01 μg/g, and the number of myopia cases was 154(51.3%); The serum selenium of 300 students in selenium-rich areas was 102.31±10.26 μg/L, the hair selenium was 0.71±0.02 μg/g, and the number of myopia cases was 90(30.0%), the serum and hair selenium in the selenium-rich areas were significantly higher than those compared with the students in selenium-deficient areas, and the myopic incidence was significantly reduced(all P&#x003C;0.01). The level of GSH-Px of the two areas was 114.65±12.12U/L vs 75.34±13.20U/L(Z=37.994, P&#x003C;0.01). There is a negative correlation between serum and hair selenium and the myopic incidence(r=-0.542, -0.621, P&#x003C;0.05).CONCLUSION:Serum and hair selenium is significantly associated with myopia of junior high school students in Enshi, which may provide new ideas for the clinical prevention and treatment of myopia.

Mechanism of ferroptosis and its research progress in lymphoma / 中国临床药理学与治疗学

Lymphoma is a common hematological malignant tumor which poses a great threat to human health. Chemotherapy, molecular targeted therapy, and hematopoietic stem cell transplantation constitute the main treatment methods for lymphoma, however, there are still some patients with lymphoma suffer from drug resistance, relapse and refractory. Ferroptosis is a newly discovered mode of programmed cell death, which is related to iron-dependent lipid peroxidation damage. Targeting ferroptosis provides a novel landscape for inhibiting the growth of lymphoma. We reviewed the mechanism of ferroptosis from the initial signals, intermediate events, effect stages, defense mechanisms and summarized the research progress of ferroptosis in lymphoma, providing novel therapeutic targets in the treatment of lymphoma.