Bone marrow necrosis: a rare complication of herbal treatment with Hypericum perforatum (St. John's wort)

A 22-year-old man presented with fever and ulceration of the oral mucosa. The patient had pharyngeal and esophageal candidiasis. For the 3 weeks prior to presentation, he had been taking approximately 1000 mg/day of flowering herbs (Hypericum perforatum L, known as St. John's wort) for treatment of depression. A complete blood count on the first day of hospitalization showed agranulocytosis and normocytic anemia. His condition worsened, and he developed progressive dysphagia. A bone marrow biopsy on day 3 revealed bone marrow necrosis. After the diagnosis was established (day 3 of hospitalization), treatment with granulocyte colony-stimulating factor 48 U/day, intravenous immunoglobulin 400 mg/kg, and amphotericin B 100 mg/day was initiated. The patient did not respond, and died within one week of the diagnosis. This cases suggests that Hypericum species may lead to severe hematologic toxicity, with conditions involving bone marrow necrosis.     

Protective effects of quercetin against hydrogen peroxide-induced apoptosis in human neuronal SH-SY5Y cells

Hydrogen peroxide (H₂O₂) is a major reactive oxygen species that has been implicated in various neurodegenerative diseases. Quercetin, one of the plant flavonoids, has been reported to harbor various physiological properties including antioxidant activity. In this study, we investigated the neuroprotective effects of quercetin against H₂O₂-induced apoptosis in human neuronal SH-SY5Y cells. H₂O₂-mediated cytotoxicity and lactate dehydrogenase release were suppressed in a quercetin concentration-dependent manner. In addition, quercetin repressed the expression of the pro-apoptotic Bax gene and enhanced that of the anti-apoptotic Bcl-2 gene in SH-SY5Y cells. Moreover, quercetin effectively inhibited the activation of the caspase cascade that leads to DNA fragmentation, a key feature of apoptosis, and subsequent cell death. These results indicate the importance of quercetin in protecting against H₂O₂-mediated neuronal cell death. Thus, quercetin might potentially serve as an agent for prevention of neurodegenerative diseases caused by oxidative stress and apoptosis.     

St john's wort (Hypericum perforatum) counteracts deleterious effects of the chronic restraint stress on recall in rats

This study aimed at verifying a hypothesis that St. John's wort (Hypericum perforatum) alleviates stress-induced memory impairments. Administration of Hypericum perforatum (350 mg kg(-1) daily for 21 days) significantly enhanced recall of passive avoidance behavior (PAB), but had no effect on the acquisition of conditioned avoidance responses (CARs). Rats stressed chronically (2 h daily for 21 days) displayed diminished recall of the PAB and this effect was abolished by St John's wort. Chronic administration of the "equivalent" to the stress dose of exogenous corticosterone (5 mg kg(-1) daily for 21 days) also impaired recall of PAB, and this effect was also reversed by Hypericum perforatum. None of our treatments produced significant motor coordination impairments as tested in a 'chimney' test. It appears that H. perforatum prevents stress-induced deterioration of memory in rats.     

Black cohosh and St. John's wort (GYNO-Plus) for climacteric symptoms

PURPOSE: This study was conducted to investigate the efficacy of black cohosh (Cimicifuga racemosa) and St. John's wort (Hypericum perforatum) in women with climacteric symptoms, and to assess their effects on vaginal atrophy, hormone levels, and lipid profiles. MATERIALS AND METHODS: In this double-blind randomized, placebo-controlled, multicenter study, 89 peri- or postmenopausal women experiencing climacteric symptoms were treated with St. John's wort and black cohosh extract (Gynoplus), Jin-Yang Pharm., Seoul, Korea) or a matched placebo for 12 weeks. Climacteric complaints were evaluated by the Kupperman Index (KI) initially and at 4 and 12 weeks following treatment. Vaginal maturation indices, serum estradiol, FSH, LH, total cholesterol, HDL- cholesterol, LDL-cholesterol, and triglyceride levels were measured before and after treatment. From the initial 89 participants, 77 completed the trial (42 in the Gynoplus group, 35 in the placebo group). RESULTS: Baseline characteristics were not significantly different between the two groups. Mean KI scores and hot flushes after 4 and 12 weeks were significantly lower in the Gynoplus group. Differences in superficial cell proportion were not statistically significant. HDL levels decreased in the control group from 60.20 +/- 16.37 to 56.63 +/- 12.67, and increased in the Gynoplus group from 58.32 +/- 11.64 to 59.74 +/- 10.54; this was statistically significant (p=0.04). CONCLUSION: Black cohosh and St. John's wort combination was found to be effective in alleviating climacteric symptoms and might provide benefits to lipid metabolism.     

西红花酸对H_2O_2诱导PC12细胞损伤的保护作用

目的通过H2O2诱导PC12细胞损伤,建立氧化应激损伤的体外模型,以探讨西红花酸对细胞损伤的保护作用及其相关机制。方法观察不同浓度(0、50、100、200、300、400μmol/L)H2O2损伤PC12细胞12 h,用CCK-8检测细胞活力;不同浓度(0.1、1、5、10μmol/L)西红花酸预处理PC12细胞24 h,观察西红花酸对H2O2(200μmol/L)损伤细胞后的恢复作用,CCK-8检测细胞活力;罗丹明Rh123染色,流式检测线粒体膜电位(MMP);DCF-DA染色荧光照相术检测活性氧(ROS)水平;Western blot检测磷酸化ERK1/2的表达情况。结果 H2O2(0～400μmol/L)作用PC12细胞12 h后,细胞活力分别为(100±4.1)%、(102±1.9)%、(89±11.2)%、(52±2.6)%、(42±1.6)%、(8±0.4)%,细胞损伤呈明显的浓度依耐性;西红花酸预处理后,细胞活力由(45.12±3.15)%,分别上升为(51.88±4.24)%、(65.14±8.19)%、(57.66±5.58)%、(53.61±4.57)%;西红花酸(1μmol/L、5μmol/L)预处理组减少了线粒体膜电位(MMP)的下降,有效清除活性氧(ROS),激活磷酸化ERK1/2。结论上述实验表明西红花酸能对抗H2O2诱导的氧化应激损伤,表明西红花酸有抗氧化作用。     

Protective effect of trihexyphenidyl on hydrogen peroxide-induced oxidative damage in PC12 cells

The protective effect of trihexyphenidyl (THY) on hydrogen peroxide-induced oxidative damage was investigated in the rat pheochromocytoma line PC12 cells. Following the exposure of PC12 cells to H(2)O(2), there was a reduction in cell survival, activities of superoxide dismutase (SOD) and mitochondria membrane potential (MMP), in contrast, the increased levels in Lactate dehydrogenase (LDH) release, malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS), as well as intracellular [Ca(2+)]i level were observed. However, preincubation of cells with THY prior to H(2)O(2) exposure attenuated all the changes mentioned above, THY exhibited protective effect against H(2)O(2)-induced toxicity in PC12 cells, indicating that the compound may be a potential therapeutic agent for the diseases influenced by oxidative damage.     

Protective effect of quercitrin against hydrogen peroxide-induced dysfunction in osteoblastic MC3T3-E1 cells

The protective effect of quercitrin on the response of osteoblastic MC3T3-E1 cells to oxidative stress was evaluated. Osteoblasts were incubated with H₂O₂ and/or quercitrin, and markers of osteoblast function and oxidative damage were examined. Quercitrin treatment reversed the cytotoxic effect of H₂O₂ significantly (P < 0.05). This effect was blocked by ICI182780 and LY294002, suggesting that quercitrin's effect might be involved in estrogen action and results from PI3K mediated signaling pathway. Pretreatment of quercitrin increased collagen content, alkaline phosphatase (ALP) activity, and calcium deposition of osteoblasts compared with H₂O₂ treated cells and these effects were blocked by ERKs and p38 mitogen-activated protein kinases (MAPKs) inhibitors such as PD98059 and SB203580, respectively. These suggest that quercitrin-induced protective effect against osteoblast dysfunction by oxidative stress is associated with increased activation of ERKs and p38 MAPK. Pretreatment with quercitrin also reduced the increase in bone-resorbing factor, receptor activator of nuclear factor-kB ligand (RANKL) and oxidative damage markers (malondialdehyde, protein carbonyl, and nitrotyrosine) induced by H₂O₂. These results suggest that quercitrin may be protective against H₂O₂-induced dysfunction in osteoblasts.     

The efficiency of Viscum album ssp. album and Hypericum perforatum on human immune cells in vitro

Viscum album L. ssp. album and Hypericum perforatum L. are used for the treatment of different diseases. In this study, the effects of these herbals on immune cells were assessed in vitro. The phagocytosis, candidacidal activity of neutrophils and adhesion function of epithelial cells were investigated. Also, the expression of the surface markers of lymphocytes was analyzed by flow cytometry. It was observed that V. album ssp. album increased phagocytic activity and candidacidal activity of neutrophils and decreased adhesion function of epithelial cells. We also observed that in human peripheral blood mononuclear cells stimulated by Viscum album L. ssp. album the levels of CD4(+)CD25(+) and CD8(+)CD25(+) T cells, CD69 expressions in the activated T lymphocytes and CD3(-)CD16(+)CD56(+) NK cells increased compared to the cells that were not stimulated by this herbal. Whereas CD4(+)CD25(+), CD8(+)CD25(+) T cells, CD 69 expression and CD3(-)CD16(+)CD56(+) Natural killer cells did not show any significant differences with the presence of Hypericum perforatum L. compared to the control group. Hypericum perforatum L. increased candidacidal activity of neutrophils and decreased adhesion function of epithelial cells. In the light of these findings, it is considered that these extracts may be used as an adjuvant treatment option for immune activation in immunosuppressed patients.     

Synthesis of glutathione C60 derivative and its protective effect on hydrogen peroxide-induced apoptosis in rat pheochromocytoma cells

Oxidized glutathione C(60) derivative has been synthesized and characterized in our research. As a novel derivative of C(60), the glutathione C(60) derivative is soluble in dimethylsulfoxide, dimethylformamide and dimethylacetamide. Rat pheochromocytoma (PC12) cells are treated with hydrogen peroxide and underwent cytotoxicity; apoptotic death is determined by MTT assay, flow cytometry analysis, PI/Hoechst 33342 staining and glutathione assay. The results suggest that glutathione C(60) derivative has the potential to prevent oxidative stress-induced cell death without evident toxicity.     

The protective effect of hepatocyte growth-promoting factor (pHGF) against hydrogen peroxide-induced acute lung injury in rats

To examine the protective effect of hepatocyte growth-promoting factor (pHGF) in hydrogen peroxide (H(2)O(2))-induced acute lung injury in rats, we observed the pathological changes in lung tissue by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and by light and electron microscopy. We also measured the serum levels of lipid peroxide (LPO). At 6 to 24 h after H(2)O(2) injection, the level of LPO was significantly higher in the H(2)O(2) group than in the H(2)O(2) + pHGF-treated group. This finding indicated that pHGF protected against cell membrane damage in H2O2-induced acute lung injury. Positive TUNEL signals were found in capillary endothelial cells, alveolar epithelial cells, and inflammatory cells. In the H(2)O(2) + pHGF-treated group, TUNEL-positive signals were reduced compared with those in the H(2)O(2) group. This finding indicated that pHGF acts to suppress apoptosis. In the H(2)O(2) group, severe pulmonary edema was seen 3 h after H(2)O(2) injection, and at 24 h, severe atelectasis was seen. In the H(2)O(2) + pHGF-treated group, pulmonary edema was scarcely seen and severe atelectasis was not found. This finding indicated that pHGF acts to suppress both severe pulmonary edema and atelectasis. In the H(2)O(2) group, the formation of subendothelial blebs and disruption of endothelial cells was observed. Edema and disruption were seen in type I epithelial cells. In type II lung epithelial cells, mitochondria were swollen and microvilli had disappeared. In the H(2)O(2) + pHGF-treated group, the formation of subendothelial blebs was seen, but no severe subendothelial blebs were observed. Disruption of capillary endothelial cells and type I epithelial cells was not evident, nor was there damage to type II lung epithelial cells. These findings indicated that pHGF protects the progression of H(2)O(2)-induced acute lung injury, and showed that pHGF acts to stabilize the cell membrane in capillary endothelial cells and lung epithelial cells.     

Protective effect of edaravone against Alzheimer's disease-relevant insults in neuroblastoma N2a cells

Oxidative stress has been demonstrated to be involved in the pathogenesis of Alzheimer's disease (AD). Thus, antioxidant therapy may represent a promising avenue for the treatment of AD. Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a potent free radical scavenger and has been shown to provide neuroprotection in both animal models of cerebral ischemia and stroke patients. In the present study, we investigated the protective effect of edaravone against AD-relevant insults in neuroblastoma N2a cells and explored the potential mechanisms involved. N2a/Swe.Δ9 cells were used as the AD model cells, which exhibited reduced cell viability, increased apoptosis and oxidative stress as well as decreased mitochondrial membrane potential compared with N2a/Wt cells. All of these phenotypes were significantly reversed by edaravone treatment. Edaravone treatment significantly elevated cell viability, reduced apoptotic rate, attenuated oxidative stress and improved mitochondrial membrane potential in N2a/Swe.Δ9 cells. Furthermore, edaravone treatment inhibited mitochondria-dependent apoptosis pathways in N2a/Swe.Δ9 cells through decreasing the Bax/Bcl-2 ratio, attenuating cytochrome c release and suppressing the activation of caspase-3. These results demonstrate that edaravone provides neuroprotection in an AD-related in vitro model and therefore, may be a potential complement for AD therapy.     

Prevention of hydrogen peroxide-induced apoptosis of human peripheral T cells by a lysosomotropic iron chelator, ammonium chloride

Human peripheral T cells are considered to be easily susceptible to oxidative stress because these cells lack peroxidase activity. Therefore, in a previous study, we investigated the site of ROS formation by utilizing Mito-Capture, H(2)DCFDA (succinimidyl ester of dichlorodihydrofluorescein diacetate), DAPI (4',6-diamidino-2-phenylindole), and LysoSensor. Our results showed that ROS formation was apparently diffusely distributed in T cells oxidatively stressed with 0.1 mM hydrogen peroxide. Moreover, lysosomal swelling and deformity, possibly revealing lysosomal membrane destabilization, were observed in these cells. Based on the above-mentioned results, we concluded that an apoptotic cascade involving early lysosomal membrane destabilization exists in the hydrogen peroxide-induced apoptosis of human peripheral T cells. Therefore, the possible involvement of lysosomal protease leakage caused by hydroxyl radical formation in lysosomes (possibly resulting in mitochondrial membrane dysfunction) is considered to play an important role in hydrogen peroxide-induced T cell apoptosis. Hydrogen peroxide-mediated destabilization of lysosomal membranes with release of hydrolytic enzymes such as many kinds of cathepsins into the cell cytoplasm can lead to a cascade eventuating in cell death. To assess the importance of the intralysosomal pool of redox-active iron, we examined the effect of blockade of lysosomal digestion by exposing T cells to the lysosomotropic alkalinizing agent ammonium chloride (NH(4)Cl). Preincubation of human peripheral T cells with 10 mM NH(4)Cl for 4 h dramatically decreased apoptotic death caused by subsequent exposure to hydrogen peroxide (H(2)O(2)), and lysosomes and mitochondria showed almost normally preserved appearance. Therefore, we concluded here that lysosomal protease leakage caused by hydrogen peroxide in T cells was prevented by preincubation with ammonium chloride (NH(4)Cl).     

Sodium pyruvate protects against H(2)O(2) mediated apoptosis in human neuroblastoma cell line-SK-N-MC

Free radicals are involved in neuronal damage. The present study was aimed to investigate the protective effect of sodium pyruvate-a free radical scavenger against hydrogen peroxide (H(2)O(2)) induced apoptosis in human neuroblastoma cell line-SK-N-MC. On exposure to H(2)O(2) (0.025 mM) cells exhibited apoptosis within 24 h, demonstrating a high caspase 3 activity by 3 h followed by cleavage of PARP that was maximum at 24 h. A break down in the mitochondrial membrane potential was observed 3 h onwards. Sodium pyruvate protected cells significantly (P<0.05) against apoptosis in a dose dependent manner as assessed for cell viability by dye exclusion method and apoptosis by TUNEL. Sodium pyruvate significantly inhibited caspase 3 activity, cleavage of PARP and breakdown of mitochondrial membrane potential. These data suggest that sodium pyruvate protects neuronal damage caused by H(2)O(2).     

人参皂苷Re对人神经母细胞瘤SH-SY5Y细胞缺氧复氧损伤的保护作用

目的：探讨人参皂苷Re 对人神经母细胞瘤SH-SY5Y 细胞缺氧复氧损伤的保护作用。 方法：采用缺氧复 氧法制备SH-SY5Y 细胞损伤模型,分为对照组、模型组、Re 6.25 μg/mL 组和Re 12.50 μg/mL 组。采用MTT 法测定细胞存活率,四甲基罗丹明甲酯（TMRM）染色评估细胞线粒体膜电位变化,DAPI 染色观察细胞凋亡 率,并进一步采用免疫印迹检测各组细胞核因子NF-E2 相关因子2（Nrf-2）、Bax 和p53 的蛋白表达。 结果：人 参皂苷Re 对SH-SY5Y 细胞活力无显著影响;缺氧复氧条件下,细胞存活率显著降低,而人参皂苷Re 在6.25、 12.50 μg/mL 浓度下预保护可显著提高细胞存活率。缺氧复氧损伤后,人参皂苷Re 6.25、12.50 μg/mL 能显著提 高SH-SY5Y 细胞的线粒体膜电位水平和抑制SH-SY5Y 细胞的凋亡率。人参皂苷Re 能够提高Nrf-2 的蛋白表达, 抑制Bax 和p53 蛋白的表达。结论：人参皂苷Re 可以抑制缺氧复氧损伤细胞的凋亡和氧化损伤,对缺氧复氧诱导 的神经细胞具有显著的保护作用。     

Reactive oxygen species-producing site in hydrogen peroxide-induced apoptosis of human peripheral T cells: involvement of lysosomal membrane destabilization

In our previous study, we examined the effect of exogenous hydrogen peroxide, which causes a potent oxidative stress and has been demonstrated to be a potent apoptosis-inducer in many kinds of cells. We found that the addition of 1 or 10 mM hydrogen peroxide induced reactive oxygen species (ROS) formation, oxidative DNA damage, dysfunction of the mitochondrial membrane potential, and early apoptotic changes in the human osteosarcoma cell line HS-Os-1. We therefore concluded that intracellular ROS formation was involved in the hydrogen peroxide-induced apoptosis of HS-Os-1 cells. In contrast to the osteosarcoma cell line HS-Os-1, human peripheral T cells are considered to be easily susceptible to oxidative stress, because these cells lack peroxidase activity. Therefore, in this study, we investigated the site of ROS formation by utilizing MitoCapture, H2DCFDA (succinimidyl ester of dichloro-dihydrofluorescein diacetate), DAPI (4',6-diamidino-2-phenylindole), and LysoSensor. Our results showed that ROS formation was apparently diffusely distributed in T cells oxidatively stressed with 0.1 mM hydrogen peroxide. Moreover, lysosomal swelling and deformity, possibly revealing lysosomal membrane destabilization, were observed in these cells. Based on the above results, there exists an apoptotic cascade involving early lysosomal membrane destabilization in the hydrogen peroxide-induced apoptosis of human peripheral T cells. Therefore, the possible involvement of lysosomal protease leakage caused by hydroxyl radical formation in lysosomes (possibly resulting in mitochondrial membrane dysfunction) is considered to play an important role in hydrogen peroxide-induced T cell apoptosis.     

PTEN抑制剂对软脂酸引起脐静脉内皮细胞凋亡的保护作用

目的 探讨抑癌基因PTEN（phosphatase and tensin homology deleted on chromosome ten）的抑制剂双过氧钒（bpV）对软脂酸（PA）引起人脐静脉内皮细胞（HUVEC）凋亡的保护作用。方法 四甲基偶氮唑盐(MTT)测定细胞生存率;Hoechst-PI染色荧光显微镜观测细胞凋亡形态;Annexin-Ⅴ-PI流式细胞术测定细胞凋亡,Western blotting检测总PTEN和磷酸化PTEN蛋白水平,实时定量PCR测定细胞PTEN mRNA的表达。 结果 MTT显示,PA（0.2~0.6mmol/L）作用24h后可明显抑制HUVEC细胞的生长;Hoechst-PI染色荧光显微镜及Annexin-Ⅴ-PI双染流式细胞检测证实不同浓度的PA处理24h后,随着PA浓度(0.2~0.6mmol/L)的增高,其诱导HUVEC细胞的凋亡作用增强,实时定量PCR 及Western blotting显示,PA浓度(0.2~0.6mmol/L)作用细胞后PTEN的转录及活性随浓度增高而增加,并呈现一定的剂量依赖性。bpV作用细胞可以增加细胞的生存率,抑制细胞的凋亡,PTEN的转录及蛋白表达降低。结论 一定浓度范围内PA剂量依赖性诱导HUVEC细胞发生凋亡性损伤,在此过程中伴随细胞内PTEN表达上调和活性增强,PTEN抑制剂双过氧钒使细胞的凋亡作用减轻,在此过程中PTEN转录及蛋白表达降低,PTEN信号通路可能是PA诱导脐静脉内皮细胞凋亡的重要通路之一, PTEN抑制剂可抑制此通路起到对细胞的保护作用。     

Protective effects of vacuolar H+ -ATPase c on hydrogen peroxide-induced cell death in C6 glioma cells

We have isolated a gene, the c subunit (ATP6L) of vacuolar H(+)-ATPase, involved in oxidative stress response. In this study, we examined the role of ATP6L and its molecular mechanisms in glial cell death induced by H(2)O(2). Expression of the ATP6L gene was increased by H(2)O(2) treatment in C6 glial cells. ATP6L siRNA-transfected C6 cells treated with H(2)O(2) showed a significant decrease in viability. ATP6L siRNA-transfected cells that were pretreated with MEK1/2 inhibitor completely recovered cell viability. Pretreatment of the transfected cells with zVAD-fmk, a pan-specific caspase inhibitor, did not result in the recovery of cell viability, as determined by a H(2)O(2)-induced cytotoxicity assay. The ultrastructural morphology of the transfected cells as seen by the use of transmission electron microscopy showed numerous cytoplasmic autophagic vacuoles with double membrane. These results suggest that ATP6L has a protective role against H(2)O(2)-induced cytotoxicity via an inhibition of the Erk1/2 signaling pathway, leading to inhibition of autophagic cell death.     

Protection of human umbilical vein endothelial cells by glycine and structurally similar amino acids against calcium and hydrogen peroxide-induced lethal cell injury.

Cultured human umbilical vein endothelial cells treated with either the calcium ionophore, ionomycin, or ionomycin plus cyanide-m-chlorophenylhydrazone had immediate severe depletion of adenosine triphosphate, (ATP) and increases of cytosolic free calcium (Caf) and then sustained lethal cell injury as manifested by release of lactate dehydrogenase and failure to exclude vital dyes within 15 minutes. Inclusion of glycine in the experimental medium prevented the enzyme leakage for at least 60 minutes without altering the ATP depletion or increases of Caf. The physiologic glycine concentration of 0.25 mmol/l gave 50% protection, and protection was complete at 1 mmol/l. Several other small neutral amino acids, L- and D-alanine, beta-alanine, 1-aminocyclopropane-1-carboxylate, alpha-aminoisobutyrate, and L-serine, had effects similar to glycine, but other amino acids and metabolic substrates did not. The endothelial cells were relatively resistant to damage from hydrogen peroxide, but sensitivity could be increased by preloading with Fe2+. In both non-loaded and Fe(2+)-loaded cells, hydrogen-peroxide-induced lactate dehydrogenase (LDH) release developing over 180 minutes was prevented by glycine in a fashion analogous to that seen with ionomycin damage. Mn2+ also partially protected against hydrogen peroxide injury but was not required for glycine's effects. These data demonstrate that striking modulatory effects of glycine and structurally similar amino acids that have previously been characterized in most detail using kidney tubule cells are strongly expressed in human umbilical vein endothelial cells and are involved in their response to Ca2+ and oxidant-mediated damage. These amino acid effects must be considered in the design of in vitro studies of endothelial cell injury and may contribute to endothelial cell pathophysiology in vivo.