Chrysophanol‐induced cell death (necrosis) in human lung cancer A549 cells is mediated through increasing reactive oxygen species and decreasing the level of mitochondrial membrane potential

Chrysophanol (1,8‐dihydroxy‐3‐methylanthraquinone) is one of the anthraquinone compounds, and it has been shown to induce cell death in different types of cancer cells. The effects of chrysophanol on human lung cancer cell death have not been well studied. The purpose of this study is to examine chrysophanol‐induced cytotoxic effects and also to investigate such influences that involved apoptosis or necrosis in A549 human lung cancer cells in vitro. Our results indicated that chrysophanol decreased the viable A549 cells in a dose‐ and time‐dependent manner. Chrysophanol also promoted the release of reactive oxygen species (ROS) and Ca²⁺ and decreased the levels of mitochondria membrane potential (ΔΨ_m) and adenosine triphosphate in A549 cells. Furthermore, chrysophanol triggered DNA damage by using Comet assay and DAPI staining. Importantly, chrysophanol only stimulated the cytocheome c release, but it did not activate other apoptosis‐associated protein levels including caspase‐3, caspase‐8, Apaf‐1, and AIF. In conclusion, human lung cancer A549 cells treated with chrysophanol exhibited a cellular pattern associated with necrotic cell death and not apoptosis in vitro. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 740–749, 2014.     

Aflatoxin G1-induced oxidative stress causes DNA damage and triggers apoptosis through MAPK signaling pathway in A549 cells

Our previous studies showed that Aflatoxin G₁ (AFG₁) could induce lung adenocarcinoma, and that the cancer cells originated from alveolar type II cells (AT-II cells). Recently, we found AFG₁ induced structural impairment in rat AT-II cells, which may account for an early event in lung tumorigenesis. However, the mechanism of AFG₁-induced AT-II cell damage remains unclear. DNA damage and apoptosis induced by oxidative stress are well accepted causes of cell damage. Thus, we explore whether AFG₁ activates the reactive oxygen species (ROS)/MAPK/apoptosis pathway to cause cell damage in human AT-II cells like the cell line (A549). We found AFG₁ induced oxidative stress by increasing ROS generation and caused DNA double-strand breaks (DSBs) by up-regulating γH2AX expression. AFG₁ also triggered apoptosis in A549 cells by regulating Fas/FasL, caspase-8, Bax, Bcl-2, and activating caspase-3. Pre-treatment with antioxidant n-acetyl-l-cysteine (NAC) reduced ROS generation and DNA DSBs, inhibited apoptosis, and increased cell viability in AFG₁-treated cells. Furthermore, we found AFG₁ activated ROS-mediated JNK and p38 pathways to induce cell apoptosis in A549 cells. In conclusion, our results indicate that AFG₁ induces oxidative DNA damage and triggers apoptosis through ROS-mediated JNK and p38 signaling pathways in A549 cells, which may contribute to AFG₁-induced AT-II cell damage.     

Enhanced cell death effects of MAP kinase inhibitors in propyl gallate-treated lung cancer cells are related to increased ROS levels and GSH depletion

Propyl gallate (PG) has an anti-growth effect in lung cancer cells. The present study investigated the effects of mitogen-activated protein kinase (MAPK; MEK, JNK, and p38) inhibitors on PG-treated Calu-6 and A549 lung cancer cells in relation to cell death as well as reactive oxygen species (ROS) and glutathione (GSH) levels. PG induced cell death in both Calu-6 and A549 lung cancer cells at 24 h, which was accompanied by loss of mitochondrial membrane potential (MMP; ΔΨ_m). All of the tested MAPK inhibitors increased cell death in both PG-treated lung cancer cell lines. In particular, MEK inhibitor strongly enhanced cell death and MMP (ΔΨ_m) loss in PG-treated Calu-6 cells and p38 inhibitor had the same effects in A549 cells as well. PG increased ROS levels and caused GSH depletion in both cell lines at 24 h. MAPK inhibitors increased O₂^•- levels and GSH depletion in PG-treated Calu-6 cells, and JNK and p38 inhibitors increased ROS levels and GSH depletion in PG-treated A549 cells. In conclusion, MAPK inhibitors increased cell death in PG-treated Calu-6 and A549 lung cancer cells. Enhanced cell death and GSH depletion in Calu-6 cells caused by the MEK inhibitor were related to increased O₂^•- levels, and the effects of the p38 inhibitor in A549 cells were correlated with increased general ROS levels.     

Ouabain induces apoptotic cell death in human prostate DU 145 cancer cells through DNA damage and TRAIL pathways

Ouabain, a cardiotonic steroid and specific Na⁺/K⁺‐ATPase inhibitor, has a potential to induce cancer cell apoptosis but the mechanisms of apoptosis induced by ouabain are not fully understand. The aim of this study was to investigate the cytotoxic effects of ouabain on human prostate cancer DU 145 cells in vitro. Cell morphological changes were examined by phase contrast microscopy. Cell viability, cell cycle distribution, cell apoptosis, DNA damage, the production of ROS and Ca²⁺, and mitochondrial membrane potential (ΔΨ_m) were measured by flow cytometry assay. Results indicated that ouabain induced cell morphological changes, decreased total cell viability, induced G0/G1 phase arrest, DNA damage, and cell apoptosis, increased ROS and Ca²⁺ production, but decreased the levels of ΔΨ_m in DU 145 cells. Ouabain also increased the activities of caspase‐3, ‐8, and ‐9. Western blotting was used for measuring the alterations of apoptosis‐associated protein expressions in DU 145 cells and results indicated that ouabain increased the expression of DNA damage associated proteins (pATM^Ser1981, p‐H2A.X^Ser139, and p‐p53^Ser15) and ER‐stress‐associated proteins (Grp78, ATF6β, p‐PERK^Thr981, PERK, eIF2A, GADD153, CaMKIIβ, and caspase‐4) in time‐dependently. Furthermore, ouabain increased apoptosis‐associated proteins (DR4, DR5, Fas, Fas Ligand, and FADD), TRAIL pathway, which related to extrinsic pathway, promoted the pro‐apoptotic protein Bax, increased apoptotic‐associated proteins, such as cytochrome c, AIF, Endo G, caspase‐3, ‐8, and ‐9, but reduced anti‐apoptotic protein Bcl‐2 and Bcl‐x in DU 145 cells. In conclusion, we may suggest that ouabain decreased cell viability and induced apoptotic cell death may via caspase‐dependent and mitochondria‐dependent pathways in human prostate cancer DU 145 cells.     

The crude extract of Corni Fructus induces apoptotic cell death through reactive oxygen species‐modulated pathways in U‐2 OS human osteosarcoma cells

Crude extract of Corni Fructus (CECF) has been used in Traditional Chinese medicine for the treatment of different diseases for hundreds of years. The purpose of this study was to investigate the cytotoxic effects of CECF on U‐2 OS human osteosarcoma cells. Flow cytometry was used for measuring the percentage of viable cells, cell‐cycle distribution, apoptotic cells in sub‐G1 phase, reactive oxygen species (ROS), Ca²⁺ levels, and mitochondrial membrane potential (ΔΨ_m). Comet assay and 4′‐6‐diamidino‐2‐phenylindole staining were used for examining DNA damage and condensation. Western blotting was used to examine apoptosis‐associated protein levels in U‐2 OS cells after exposed to CECF. Immunostaining and confocal laser system microscope were used to examine protein translocation after CECF incubation. CECF decreased the percentage of viability, induced DNA damage and DNA condensation, G₀/G₁ arrest, and apoptosis in U‐2 OS cells. CECF‐stimulated activities of caspase‐8, caspase‐9, and caspase‐3, ROS, and Ca²⁺ production, decreased ΔΨ_m levels of in U‐2 OS cells. CECF increased protein levels of caspase‐3, caspase‐9, Bax, cytochrome c, GRP78, AIF, ATF‐6α, Fas, TRAIL, p21, p27, and p16 which were associated with cell‐cycle arrest and apoptosis. These findings suggest that CECF triggers apoptosis in U‐2 OS cells via ROS‐modulated caspase‐dependent and ‐independent pathways. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 1020–1031, 2014.     

活性氧介导5, 7- 二甲氧基黄酮增敏TRAIL 诱导肺癌细胞凋亡

目的研究5,7-二甲氧基黄酮(5,7-DMF)是否能增强肿瘤坏死因子相关凋亡诱导配体(TRAIL)诱导的人肺癌细胞凋亡及其作用机制。方法体外培养人肺癌A549细胞。MTT法测定细胞增殖活性;碘化丙啶(PI)染色流式细胞术(FCM)和ELISA试剂盒检测细胞凋亡;DCFH-DA荧光标记FCM检测细胞内活性氧(ROS)水平。结果 5,7-DMF能增强TRAIL诱导的A549细胞凋亡和ROS生成。N-乙酰半胱氨酸能有效阻断5,7-DMF与TRAIL所诱导的A549细胞凋亡及ROS生成。结论 5,7-DMF通过促进A549细胞内活性氧生成从而增强TRAIL诱导的凋亡。     

Bufalin induces apoptosis in vitro and has Antitumor activity against human lung cancer xenografts in vivo

Bufalin has been shown to be effective against a variety of cancer cells, but its role in lung cancer has never been studied in an animal model. In this study, we evaluated bufalin effects in a human lung cancer cell line NCI‐H460 both in vitro and in vivo . Bufalin caused significant cytotoxicity in NCI‐H460 cells at a concentration as low as 1 μM. DNA condensation was observed in bufalin‐treated cells in a dose‐dependent manner. Mitochondrial membrane potential (ΔΨ_m) was reduced and reactive oxygen species (ROS) were increased in bufalin‐treated NCI‐H460 cells. Levels of several proapoptotic proteins such as Fas, Fas‐ligand, cytochrome c , apoptosis protease activating factor‐1, endonuclease G, caspase‐3 and caspase‐9 were increased after bufalin treatment. At the same time, anti‐apoptotic B‐cell lymphoma 2 protein levels were reduced. Bufalin decreased glucose regulated protein‐78 gene expression but increased growth arrest‐ and DNA damage‐inducible 153 gene expression. Bufalin injected intraperitoneally in a dose‐dependent manner reduced tumor size in BALB/C nu/nu mice implanted with NCI‐H460 cells. Bufalin injection did not produce significant drug‐related toxicity in experimental animals except at a high dose (0.4 mg kg^?1). In conclusion, low concentrations of bufalin can induce apoptosis in the human lung cancer cell line NCI‐H460 in vitro . Bufalin also reduced tumor size in mice injected with NCI‐H460 cells without significant drug‐related toxicity. These results indicate that bufalin may have potential to be developed as an agent for treating human non‐small cell lung cancer. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1305–1317, 2017.     

Casticin induced apoptotic cell death and altered associated gene expression in human colon cancer colo 205 cells

Casticin, a polymethoxyflavone, derived from natural plant Fructus Viticis exhibits biological activities including anti‐cancer characteristics. The anti‐cancer and alter gene expression of casticin on human colon cancer cells and the underlying mechanisms were investigated. Flow cytometric assay was used to measure viable cell, cell cycle and sub‐G1 phase, reactive oxygen species (ROS) and Ca²⁺ productions, level of mitochondria membrane potential (ΔΨ_m) and caspase activity. Western blotting assay was used to detect expression of protein level associated with cell death. Casticin induced cell morphological changes, decreased cell viability and induced G2/M phase arrest in colo 205 cells. Casticin increased ROS production but decreased the levels of ΔΨ_m, and Ca²⁺, increased caspase‐3, ‐8, and ‐9 activities. The cDNA microarray indicated that some of the cell cycle associated genes were down‐regulated such as cyclin‐dependent kinase inhibitor 1A (CDKN1A) (p21, Cip1) and p21 protein (Cdc42/Rac)‐activated kinase 3 (PAK3). TNF receptor‐associated protein 1 (TRAP1), CREB1 (cAMP responsive element binding protein 1) and cyclin‐dependent kinase inhibitor 1B (CDKN1B) (p27, Kip1) genes were increased but matrix metallopeptidase 2 (MMP‐2), toll‐like receptor 4 (TLR4), PRKAR2B (protein kinase, cAMP‐dependent, regulatory, type II, bet), and CaMK4 (calcium/calmodulin‐dependent protein kinase IV) genes were inhibited. Results suggest that casticin induced cell apoptosis via the activation of the caspase‐ and/or mitochondria‐dependent signaling cascade, the accumulation of ROS and altered associated gene expressions in colo 205 human colon cancer cells.     

D-氨基葡萄糖衍生物诱导Eca-109细胞凋亡的机制

目的探讨2-(3-羧基-1-丙酰氨基)-2-脱氧-D-葡萄糖{2-[(3-carboxy-1-oxoprogy1)amino]-2-deoxy-D-Glucose,CO-PADG}诱导Eca-109细胞凋亡的机制。方法不同浓度COPADG作用于人食管癌Eca-109细胞24h,检测Eca-109细胞的抑制率、凋亡率、细胞内活性氧(reactive oxygen spe-cies,ROS)、线粒体跨膜电位。结果Eca-109细胞凋亡率与COPADG浓度呈正相关,r=1.0,P<0.01;Eca-109细胞线粒体膜电位水平与Eca-109细胞凋亡率相关,r=1.0,P<0.01;ROS水平与Eca-109细胞凋亡率呈正相关,r=1.0,P<0.01;ROS水平与Eca-109细胞线粒体膜电位水平呈负相关,r=1.0,P<0.01。结论COPADG可促进Eca-109细胞凋亡,提高Eca-109细胞内ROS水平,并降低线粒体膜电位。实验结果提示COPADG提高ROS,降低Eca-109细胞线粒体膜电位启动细胞凋亡通路促使Eca-109细胞凋亡,并且线粒体膜电位的下降是通过提高ROS实现的。     

Corosolic acid induces apoptotic cell death in human lung adenocarcinoma A549 cells in vitro

Corosolic acid (CRA), a triterpenoid from medicinal herbs, has been shown to induce apoptosis in several cell lines, with the exception of A549 cells. In this report, we investigated the apoptotic effect and mechanism of CRA in A549 cells. The present study shows that CRA significantly inhibits cell viability in a concentration- and time-dependent manner. Exposure to CRA induces sub-G1 cell cycle arrest and causes apoptotic death in A549 cells. CRA also triggers the activation of caspases and poly(ADP-ribose) polymerase, an effect antagonized by z-vad-fmk. In addition, exposure to CRA leads to a significant increase in the levels of reactive oxygen species (ROS) inA549 cells. Furthermore, exposure to the ROS scavenger N acetylcysteine (NAC)prevents CRA-induced apoptosis, suggesting a role for ROS in CRA-induced apoptosis. ROS are critical regulators of caspase-mediated apoptosis in A549 cells. These results indicate that CRA induces mitochondria-mediated and caspase-dependent apoptosis inA549 cells by altering anti-apoptotic proteins in a ROS-dependent manner.     

Nonylphenol‐induced apoptotic cell death in mouse TM4 Sertoli cells via the generation of reactive oxygen species and activation of the ERK signaling pathway

Nonylphenol (NP), a representative endocrine disruptor, interferes with reproductive function in aquatic organisms and animals. Although many previous studies have focused on apoptotic cell death by NP, the fundamental mechanism of NP on apoptosis remains poorly understood. Here, we investigated the molecular mechanism on NP‐induced apoptotic cell death in mouse TM4 Sertoli cells. To evaluate NP treatment on cell viability, formazan and lactate dehydrogenase (LDH) assays were performed. Results indicate that NP reduced cell viability and increased the release of LDH in dose‐ and time‐dependent manners. The reduction of cell viability by NP treatment appeared to involve necrosis as well as apoptosis based on nuclear fragmentation, an increase in the sub G1 population, and the detection of poly(ADP ribose) polymerase and caspase‐3 cleavage. Additionally, the anti‐apoptotic protein Bcl‐2 diminished, whereas the pro‐apoptotic protein Bax increased in a time‐dependent manner. Note that NP‐induced apoptotic cell death was enhanced by the generation of reactive oxygen species (ROS) and activation of extracellular signal‐regulated kinase (ERK) signaling. Pretreatment with N‐acetylcysteine, an antioxidant, attenuated NP‐induced apoptotic cell death. Moreover, NP caused a transient activation of the MAPK pathway. In particular, NP‐induced cell death was significantly suppressed by U0126, a specific inhibitor of ERK. Taken together, our results suggest that NP induces apoptosis in mouse TM4 Sertoli cells via ROS generation and ERK activation. Copyright © 2013 John Wiley & Sons, Ltd.     

Multi-walled carbon nanotubes induce oxidative stress and apoptosis in human lung cancer cell line-A549

Abstract

Multi-walled carbon-nanotubes (MWCNTs)-induced apoptotic changes were studied in human lung epithelium cell line-A549. Non-cytotoxic doses of MWCNTs were identified using tetrazolium bromide salt (MTT) and lactate dehydrogenase (LDH) release assays. Cells were exposed to MWCNTs (0.5–100 μg/ml) for 6–72 h. Internalization and characterization of CNTs was performed by electron microscopy. Apoptotic changes were estimated by nuclear condensation, DNA laddering, and confirmed by expression of associated markers: p⁵³, p^21WAF1/CIP1, Bax, Bcl₂ and activated caspase-3. MWCNTs induced the production of reactive oxygen species and malondialdehyde along with significant decrease in the activity of catalase and glutathione. MWCNTs-induced ROS generation was found not to be associated with the mitochondrial activity. In general, the changes were significant at 10 and 50 μg/ml only. Results indicate the involvement of oxidative stress and apoptosis in A549 cells exposed to MWCNTs. Our studies provide insights of the mechanisms involved in MWCNTs-induced apoptosis at cellular level.     

The role of reactive oxygen species in the genotoxicity of surface-modified magnetite nanoparticles

The generation of reactive oxygen species (ROS) has been proposed as the underlying mechanism involved in the genotoxicity of iron oxide nanoparticles. The data published to date are, however, inconsistent, and the mechanism underlying ROS formation has not been completely elucidated. Here, we investigated the capacity of several surface-modified magnetite nanoparticles (MNPs) to generate ROS in A549 human lung adenocarcinoma epithelial cells and HEL 12469 human embryonic lung fibroblasts. All MNPs, regardless of the coating, induced significant levels of DNA breakage in A549 cells but not in HEL 12469 cells. Under the same treatment conditions, variable low levels of intracellular ROS were detected in both A549 and HEL 12469 cells, but compared with control treatment, none of the coated MNPs produced any significant increase in oxidative damage to DNA in either of these cell lines. Indeed, no significant changes in the total antioxidant capacity and intracellular glutathione levels were observed in MNPs-treated human lung cell lines regardless of surface coating. In line with these results, none of the surface-modified MNPs increased significantly the GPx activity in A549 cells and the SOD activity in HEL 12469 cells. The GPx activity was significantly increased only in SO-Fe₃O₄-treated HEL 12469 cells. The SOD activity was significantly increased in SO-PEG-PLGA-Fe₃O₄-treated A549 cells but significantly decreased in SO-Fe₃O₄-treated A549 cells. Our data indicate that oxidative stress plays, at most, only a marginal role in the genotoxicity of surface-modified MNPs considered in this study in human lung cells.     

New 6(17)-epoxylathyrane diterpene: aellinane from Euphorbia aellenii induces apoptosis via mitochondrial pathway in ovarian cancer cell line

Euphorbia species have been used in traditional medicine in many countries for the treatment of cancer. This article aims to evaluate the capability of a new lathyrane diterpene isolated from Euphorbia aellenii to induce apoptosis in the Caov-4 cell line to determine the underlying mechanism of its anticancer effects. A new 6(17)-epoxylathyrane diterpenes: aellinane from Euphorbia aellenii was evaluated for viability of Caov-4 cells by MTT method. Apoptosis induction by lathyrane diterpene was confirmed by annexin V-FITC/PI staining, and caspase-6 activation. The Bcl2 and Bax protein content were detected by Western blot analysis. Finally, we employed the fluorescent ROS detection kit and fluorochrome JC-1 to determine ROS levels and loss of mitochondria membrane potential (ΔΨm) in Caov-4 cells, respectively. The results show that lathyrane diterpene has significant cytotoxic effect against Caov-4 cells. The IC50 value was 45?μM. Annexin V/propidium iodide (PI) staining and caspase-6 activity assay confirmed that lathyrane diterpene is able to induce apoptosis in Caov-4 cells. The results also demonstrate that lathyrane diterpene up-regulated Bax and down-regulated Bcl-2 proteins. Moreover, apoptotic effect of lathyrane diterpene was also related to ROS production and loss of mitochondrial membrane potential (ΔΨm). This study demonstrated that lathyrane diterpene has profound activity against Caov-4 cells. Analysis of apoptosis-related proteins revealed that lathyrane diterpene triggered the mitochondrion-mediated apoptosis pathway, which led to the loss of mitochondrial membrane potential (ΔΨm) and activation of caspase-6. Therefore, we believe that lathyrane diterpene might be a promising natural compound in ovarian cancer therapy.     

Lipopolysaccharide induces apoptotic insults to human alveolar epithelial A549 cells through reactive oxygen species-mediated activation of an intrinsic mitochondrion-dependent pathway

Alveolar type II epithelial cells can regulate immune responses to sepsis-induced acute lung injury. Lipopolysaccharide (LPS), an outer membrane component of Gram-negative bacteria, can cause septic shock. This study was designed to evaluate the cytotoxic effects of LPS on human alveolar epithelial A549 cells and its possible molecular mechanisms. Exposure of A549 cells to LPS decreased cell viability in concentration- and time-dependent manners. In parallel, LPS concentration- and time-dependently induced apoptosis of A549 cells. Meanwhile, LPS only at a high concentration of 10 μg/ml caused mildly necrotic insults to A549 cells. In terms of the mechanism, exposure of A549 cells to LPS increased the levels of cellular nitric oxide and reactive oxygen species (ROS). Pretreatment with N-acetylcysteine (NAC), an antioxidant, significantly lowered LPS-caused enhancement of intracellular ROS in A549 cells and simultaneously attenuated the apoptotic insults. Sequentially, treatment of A549 cells with LPS caused significant decreases in the mitochondrial membrane potential and biosynthesis of adenosine triphosphate. In succession, LPS triggered the release of cytochrome c from the mitochondria to the cytoplasm. Activities of caspase-9 and caspase-6 were subsequently augmented following LPS administration. Consequently, exposure of A549 cells induced DNA fragmentation in a time-dependent manner. Pretreatment of A549 cells with NAC significantly ameliorated LPS-caused alterations in caspase-9 activation and DNA damage. Therefore, this study shows that LPS specifically induces apoptotic insults to human alveolar epithelial cells through ROS-mediated activation of the intrinsic mitochondrion–cytochrome c-caspase protease mechanism.     

Cytotoxic effects of incense particles in relation to oxidative stress,the cell cycle and F-actin assembly

Epidemiological studies have suggested that combustion-derived smoke, such as that produced during incense burning, is a deleterious air pollutant. It is capable of initiating oxidative stress and mutation; however, the related apoptotic processes remain unclear. In order to elucidate the biological mechanisms of reactive oxygen species (ROS)-induced respiratory toxicology, alveolar epithelial A549 cells were exposed to incense particulate matter (PM), with and without antioxidant N-acetyl-l-cysteine (NAC). The cross-linking associations between oxidative capacity, cell cycle events, actin cytoskeletal dynamics and intracellular calcium signals were investigated. An incense PM suspension caused significant oxidative stress in A549 cells, as shown by inhibition of the cell cycle at G1 and G2/M check-points, and the induction of apoptosis at Sub-G1. At the same time, alterations in the F-actin filamentous assemblies were observed. The levels of intracellular Ca²⁺ were increased after incense PM exposure. Antioxidant NAC treatment revealed that oxidative stress and F-actin remodelling was significantly mitigated. This suggests that ROS accumulation could alter cell cycle regulation and anomalous remodelling of the cortical cytoskeleton that allowed impaired cells to enter into apoptosis. This study has elucidated the integral patho-physiological interactions of incense PM and the potential mechanisms for the development of ROS-driven respiratory impairment.     

Protective effects of β‐sheet breaker α/β‐hybrid peptide against amyloid β‐induced neuronal apoptosis in vitro

Alzheimer's disease is most common neurodegenerative disorder and is characterized by increased production of soluble amyloid‐β oligomers, the main toxic species predominantly formed from aggregation of monomeric amyloid‐β (Aβ). Increased production of Aβ invokes a cascade of oxidative damages to neurons and eventually leads to neuronal death. This study was aimed to investigate the neuroprotective effects of a β‐sheet breaker α/β‐hybrid peptide (BSBHp) and the underlying mechanisms against Aβ₄₀‐induced neurotoxicity in human neuroblastoma SH‐SY5Y cells. Cells were pretreated with the peptide Aβ₄₀ to induce neurotoxicity. Assays for cell viability, cell membrane damage, cellular apoptosis, generation of reactive oxygen species (ROS), intracellular free Ca²⁺, and key apoptotic protein levels were performed in vitro. Our results showed that pretreatment with BSBHp significantly attenuates Aβ₄₀‐induced toxicity by retaining cell viability, suppressing generation of ROS, Ca²⁺ levels, and effectively protects neuronal apoptosis by suppressing pro‐apoptotic protein Bax and up‐regulating antiapoptotic protein Bcl‐2. These results suggest that α/β‐hybrid peptide has neuroprotective effects against Aβ₄₀‐induced oxidative stress, which might be a potential therapeutic agent for treating or preventing neurodegenerative diseases.