Mitochondria-dependent Apoptosis Pathway Research Articles

Antitumor effects of polydopamine coated hydroxyapatite nanoparticles and its mechanism: Mitochondria-targeted ROS and calcium channels

Nano hydroxyapatite (nHA) has been acknowledged for its inhibition efficiency on tumor cells and its excellent biocompatibility for normal tissue and cells. However, the low inhibitory efficiency of tumor cells and the ambiguous inhibitory mechanism limited its further application. In this work, four kinds of nHA with different sizes was prepared, and the one with the highest inhibition efficiency on 4T1 cells was screened as a substrate for developing the nanoparticles coated with polydopamine (PDA) coating, which was named nHA-PDA. Both in vivo and in vitro experiments were employed, and the results showed significantly higher inhibitory activity against 4T1 cells and 4T1-bared tumors by nHA-PDA. Further investigation revealed that the oxidative stress induced by PDA results in a large Reactive Oxygen Species (ROS) accumulation, thus triggering the mitochondria-dependent apoptosis pathway ROS-JNK/MAPK and inducing the cascade reaction of inhibiting the anti-apoptosis protein-Bcl-2 expression and activating the expression of the critical genes in apoptosis signaling pathway (caspase 3 and caspase 9). Besides, the significant increase of intracellular [Ca2+] may also be an essential reason for the damage of mitochondria, eventually leading to apoptosis.

The Protective Effects of Syringic Acid on Bisphenol A-Induced Neurotoxicity Possibly Through AMPK/PGC-1α/Fndc5 and CREB/BDNF Signaling Pathways.

Bisphenol A (BPA), an endocrine disruptor, is commonly used to produce epoxy resins and polycarbonate plastics. Continuous exposure to BPA may contribute to the development of diseases in humans and seriously affect their health. Previous research suggests a significant relationship between the increased incidence of neurological diseases and the level of BPA in the living environment. Syringic acid (SA), a natural derivative of gallic acid, has recently considered much attention due to neuromodulator activity and its anti-oxidant, anti-apoptotic, and anti-inflammatory effects. Therefore, in this study, we aimed to investigate the effects of SA on oxidative stress, apoptosis, memory and locomotor disorders, and mitochondrial function, and to identify the mechanisms related to Alzheimer's disease (AD) in the brain of rats receiving high doses of BPA. For this purpose, male Wistar rats received BPA (50, 100, and 200mg/kg) and SA (50mg/kg) for 21days. The results showed that BPA exposure significantly altered the rats' neurobehavioral responses. Additionally, BPA, by increasing the level of ROS, and MDA level, increased the level of oxidative stress while reducing the level of antioxidant enzymes, such as SOD, CAT, GPx, and mitochondrial GSH. The administration of BPA at 200mg/kg significantly decreased the expression of ERRα, TFAM, irisin, PGC-1α, Bcl-2, and FNDC5, while it increased the expression of TrkB, cytochrome C, caspase 3, and Bax. Moreover, the Western blotting results showed that BPA increased the levels of P-AMPK, GSK3b, p-tau, and Aβ, while it decreased the levels of PKA, P-PKA, Akt, BDNF, CREB, P-CREB, and PI3K. Meanwhile, SA at 50mg/kg reversed the behavioral, biochemical, and molecular changes induced by high doses of BPA. Overall, BPA could lead to the development of AD by affecting the mitochondria-dependent apoptosis pathway, as well as AMPK/PGC-1α/FNDC5 and CREB/BDNF/TrkB signaling pathways, and finally, by increasing the expression of tau and Aβ proteins. In conclusion, SA, as an antioxidant, significantly reduced the toxicity of BPA.

Investigation of mitochondria-dependent apoptosis pathway and lipid peroxidation level induced by biosynthesized silver nanoparticles: caspase-3 activation, BAK1/BCLx regulation and malondialdehyde production

Nowadays, silver nanoparticles (AgNPs) have attracted the attention of many researchers due to their special physical, chemical, and biological properties. There is strong evidence that biogenic AgNPs can act as potent anticancer agents through the production of reactive oxygen species (ROS) and initiate the mitochondrial pathway of apoptosis. That is why we decided to use Nepeta bracteata Benth flower extract for the first time to bio-synthesize AgNPs and study their cytotoxic and apoptotic effects on SK-BR-3 cells. AgNPs were biosynthesized at 70 °C after mixing silver nitrate and flower extract with a specific ratio and concentration, then were characterized using various analytical techniques, such as FESEM, FTIR, EDS, and zeta potential. Studies have shown that AgNPs have an irregular and circular shape, with about 99% by weight of silver, carbon, and oxygen. On the other hand, the appropriate size (below 57 nm) and surface charge (− 11.52 mV) make them stable in biological fluids. The better cytotoxic effect of AgNPs compared to flower extract on SK-BR-3 cells was investigated using the MTT method. The positive effect of AgNPs on inhibiting the growth of SK-BR-3 breast cancer cells was again confirmed by the sulforhodamine B staining method, so that AgNPs were able to decrease the density of cancer cells in a concentration-dependent manner. In addition, the flow cytometry test proved that biosynthesized AgNPs using Nepeta bracteata Benth flower extract can induce apoptosis in SK-BR-3 cancer cells. Real-time PCR then proved that the ratio of Bak1/Bclx, as well as caspase-3 expression, was increased due to active ROS-producing biomolecules present in the plant extract, and therefore, AgNPs can activate the mitochondria-dependent apoptosis pathway in breast cancer cells. Finally, their negligible oxidative stress on erythrocytes was confirmed by the lipid peroxidation method and showed that biosynthesized AgNPs can be used for breast cancer treatment without showing adverse effects on erythrocytes.

Aureusidin ameliorates 6-OHDA-induced neurotoxicity via activating Nrf2/HO-1 signaling pathway and preventing mitochondria-dependent apoptosis pathway in SH-SY5Y cells and Caenorhabditis elegans

Movement disorder Parkinson's disease (PD) is the second most common neurodegenerative disease in the world after Alzheimer's disease, which severely affects the quality of patients' lives and imposes an increasingly heavy socioeconomic burden. Aureusidin is a kind of natural flavonoid compound with anti-inflammatory and anti-oxidant activities, while its pharmacological action and mechanism are rarely reported in PD. This study aimed to explore the neuroprotective effects and potential mechanisms of Aureusidin in PD. The present study demonstrated that Aureusidin protected SH-SY5Y cells from cell damage induced by 6-hydroxydopamine (6-OHDA) via inhibiting the mitochondria-dependent apoptosis and activating the Nrf2/HO-1 antioxidant signaling pathway. Additionally, Aureusidin diminished dopaminergic (DA) neuron degeneration induced by 6-OHDA and reduced the aggregation toxicity of α-synuclein (α-Syn) in Caenorhabditis elegans (C. elegans.) In conclusion, Aureusidin showed a neuroprotective effect in the 6-OHDA-induced PD model via activating Nrf2/HO-1 signaling pathway and prevented mitochondria-dependent apoptosis pathway, and these findings suggested that Aureusidin may be an effective drug for the treatment of PD.

Green tea catechin prevents oxidative stress-regulated autophagy and apoptosis signaling, and inhibits tenderness in postmortem bovine longissimus thoracis et lumborum muscle.

Although green tea catechin has been reported to be an antioxidant and preservative in meat, the extent to which it affects the tenderization of bovine muscle remains largely unknown. This study seeks to evaluate the effect of catechin on the interplay between apoptosis and autophagy, and subsequently, the development of bovine muscle tenderness. The results indicate that catechin significantly alleviated oxidative stress. A concomitant reduction of autophagic markers LC3-II/LC3-I ratio, Beclin-1, and Atg7 levels were caused by catechin. Besides, aforementioned autophagy inhibition was further augmented by PI3K/Akt/mTOR activation. Additionally, catechin protected against mitochondrial dysfunction and inhibited mitochondria-dependent caspase apoptosis pathway. Furthermore, there was a reciprocal inhibition between autophagy and apoptosis. Ultimately, tenderness at 24 and 120h, an increase in the gap between muscle fiber bundles, and disintegration of myofibrillar architectures were all inhibited by catechin. Therefore, despite alleviating oxidative stress, catechin may hamper tenderization pattern of postmortem bovine muscle.

Ligustrazine-Derived Chalcones-Modified Platinum(IV) Complexes Intervene in Cisplatin Resistance in Pancreatic Cancer through Ferroptosis and Apoptosis.

Developing multitarget platinum(IV) prodrugs is an important strategy to attenuate cisplatin (CDDP) resistance in tandem with reduced toxicity. Herein, six novel ligustrazine-derived chalcones-modified platinum(IV) complexes were synthesized and evaluated for their anti-proliferative activities. Among them, 16a displayed higher cytotoxicity toward the tested cancer cell lines and lower cytotoxicity toward the human normal cells than CDDP or the combined group. Mechanistic studies revealed that 16a efficiently induced DNA damage and initiated a mitochondria-dependent apoptosis pathway. Besides, 16a significantly triggered ferroptosis by down-regulating expression levels of nuclear factor erythroid 2-related factor 2, glutathione peroxidase 4, and solute carrier family 7 member 11. Further, 16a obtained superior in vivo anti-tumor efficiency than CDDP in CDDP-resistant pancreatic cancer xenograft models but showed no significant side effects. In summary, our study suggested that 16a acts via a different anti-cancer mechanistic pathway than CDDP and may therefore encompass a novel practical strategy for cancer treatment.

PGAM5 exacerbates acute renal injury by initiating mitochondria-dependent apoptosis by facilitating mitochondrial cytochrome c release.

Acute kidney injury (AKI) is a worldwide public health problem characterized by the massive loss of tubular cells. However, the precise mechanism for initiating tubular cell death has not been fully elucidated. Here, we reported that phosphoglycerate mutase 5 (PGAM5) was upregulated in renal tubular epithelial cells during ischaemia/reperfusion or cisplatin-induced AKI in mice. PGAM5 knockout significantly alleviated the activation of the mitochondria-dependent apoptosis pathway and tubular apoptosis. Apoptosis inhibitors alleviated the activation of the mitochondria-dependent apoptosis pathway. Mechanistically, as a protein phosphatase, PGAM5 could dephosphorylate Bax and facilitate Bax translocation to the mitochondrial membrane. The translocation of Bax to mitochondria increased membrane permeability, decreased mitochondrial membrane potential and facilitated the release of mitochondrial cytochrome c (Cyt c) into the cytoplasm. Knockdown of Bax attenuated PGAM5 overexpression-induced Cyt c release and tubular cell apoptosis. Our results demonstrated that the increase in PGAM5-mediated Bax dephosphorylation and mitochondrial translocation was implicated in the development of AKI by initiating mitochondrial Cyt c release and activating the mitochondria-dependent apoptosis pathway. Targeting this axis might be beneficial for alleviating AKI.

Iodine-Biofortified Lettuce Can Promote Mitochondrial Dependent Pathway of Apoptosis in Human Gastrointestinal Cancer Cells.

Previously, our research provided evidence that exposure of gastric and colon cancer cells to extracts from iodine-biofortified lettuce leads to a reduction of cell viability and proliferation through cell cycle arrest and upregulation of pro-apoptotic genes. The aim of the present study was to determine the potential cellular mechanisms of induction of cell death in human gastrointestinal cancer cell lines after treatment with iodine-biofortified lettuce. We demonstrated that extracts from lettuce enriched with iodine induce apoptosis in gastric AGS and colon HT-29 cancer cells and the mechanism of programmed cell death may be triggered and executed through different signaling pathways, depending on the type of cells. Western blot analysis revealed that iodine-fortified lettuce leads to cell death through the release of cytochrome c to the cytosolic fraction and activation of the primary drivers of apoptosis: caspase-3, caspase-7, and caspase-9. Furthermore, we have reported that apoptotic effects of lettuce extracts may be mediated by poly (ADP-ribose) polymerase (PARP) and activation of pro-apoptotic Bcl-2 family proteins such as Bad, Bax, and BID. We also observed mitochondrial dysfunction with the dissipation of the mitochondrial membrane potential in cells exposed to lettuce extracts. Taken together, these results indicate that the organic form of iodine such as 5-ISA and 3,5-diISA is an important factor in the activation of intrinsic mitochondrial apoptotic pathway in AGS and HT-29 cancer cells in a p53-independent manner.

Effect of Curcumin on the Head and Neck Squamous Cell Carcinoma Cell Line HN5.

Curcumin has been isolated from the rhizomes of Curcuma longa. Over the years, it has shown outstanding therapeutic potential in various human disorders, including cancers. The aim is to study curcumin's effects on the apoptosis signaling pathway in the head and neck squamous cell carcinoma (HNSCC) cell line HN5. The cytotoxicity of curcumin on HN5 cells were assessed. In addition, HN5 cells were also treated with curcumin to evaluate its effect on the caspase-8, -9, Bcl-2, Bax, and Stat3 gene expressions. The results exhibited that cell viability reduced following curcumin treatment in a concentration- dependent manner. Curcumin treatment caused decreased expression of Bcl2, with simultaneous upregulation of the Bax/Bcl2 ratio. Curcumin increased caspase-9 expression, did not affect caspase-8, and decreased Stat3 expression. The induction of the mitochondria-dependent apoptosis pathway of curcumin happened by modulating the expression of Bcl2 and Bax genes, resulting in the caspase-9 activation. Furthermore, curcumin decreased the expression of the Stat3 in HN-5 cells. In conclusion, curcumin showed marked anticancer effects in the HN-5 cell line by modulating Stat-3; Bax/Bcl-2 expression in vitro.

Targeting the p53 signaling pathway in cancers: Molecular mechanisms and clinical studies.

Tumor suppressor p53 can transcriptionally activate downstream genes in response to stress, and then regulate the cell cycle, DNA repair, metabolism, angiogenesis, apoptosis, and other biological responses. p53 has seven functional domains and 12 splice isoforms, and different domains and subtypes play different roles. The activation and inactivation of p53 are finely regulated and are associated with phosphorylation/acetylation modification and ubiquitination modification, respectively. Abnormal activation of p53 is closely related to the occurrence and development of cancer. While targeted therapy of the p53 signaling pathway is still in its early stages and only a few drugs or treatments have entered clinical trials, the development of new drugs and ongoing clinical trials are expected to lead to the widespread use of p53 signaling-targeted therapy in cancer treatment in the future. TRIAP1 is a novel p53 downstream inhibitor of apoptosis. TRIAP1 is the homolog of yeast mitochondrial intermembrane protein MDM35, which can play a tumor-promoting role by blocking the mitochondria-dependent apoptosis pathway. This work provides a systematic overview of recent basic research and clinical progress in the p53 signaling pathway and proposes that TRIAP1 is an important therapeutic target downstream of p53 signaling.

Synthesis, characterization, and cytotoxicity analysis of selenium nanoparticles stabilized by Morchella sextelata polysaccharide

Natural bioactive molecules have been widely used as stabilizers in the functional improvement of selenium nanoparticles (SeNPs) in recent years. In this study, Morchella sextelata polysaccharide (MSP) was introduced as a novel stabilizer for the synthesis of SeNPs based on the redox system of sodium selenite and ascorbic acid. The size, morphology, stability, and anti-cancer cell activities were respectively analyzed by various methods. The results showed that the synthesized SeNPs with MSP were 72.07 ± 0.53 nm in size, red in color, spherical in shape, and amorphous in nature. MSP-SeNPs showed high scavenging activity against DPPH and ABTS radicals. And, these MSP-SeNPs exhibited a significant anti-proliferation effect on human liver (HepG2) and cervical cancer (Hela) cells in vitro, while no significant cytotoxicity against normal human kidney cells (HK−2) was observed. Moreover, the mitochondria-dependent apoptosis pathway triggered by MSP-SeNPs in HepG2 cell was identified. The expression levels of p53, Bax, cytochrome c, caspase-3 and caspase-9 were all up-regulated in HepG2 cells after MSP-SeNPs treatment, while Bcl-2 expression was down-regulated. These results suggest that MSP-SeNPs have strong potential as the food supplement for application in cancer chemoprevention.

Japanese encephalitis virus induces apoptosis by activating the RIG-1 signaling pathway.

Japanese encephalitis virus (JEV) infection can cause brain tissue lesions characterized by neuronal death, and apoptosis is involved in JEV-induced neuronopathy. In the present study, mouse microglia were infected with JEV, and pyknosis with dark-staining nuclei of infected cells was detected using Hoechst 33342 staining. TUNEL staining showed that JEV infection promoted the apoptosis of BV2 cells, and the apoptosis rate was significantly increased at 24-60 hours postinfection (hpi) (P < 0.01) and was the highest at 36 h (P < 0.0001). Western blot results showed that the expression of the Bcl-2 protein in JEV-infected cells was downregulated significantly at 60 hpi (P < 0.001), whereas that of the Bax protein was observably upregulated at 60 hpi (P < 0.001). At the same time, the level of cytochrome c (Cyt c) was significantly increased (P < 0.001), and the expression levels of two apoptosis-related proteins, namely, cleaved caspase-3 (P < 0.01) and caspase-9 (P < 0.001), were elevated significantly. Immunofluorescence staining showed that the amount of Cyt c increased with time after infection. After BV2 cells were infected with JEV, the expression of RIG-1 increased significantly from 24 hpi to 60 h (P < 0.001). The expression of MAVS increased significantly at 24 h (P < 0.001) and decreased gradually from 24 h to 60 hpi. The expression of TBK1 and NF-κB (p65) was not significantly changed. The expression of p-TBK1 and p-NF-κB (p-p65) increased significantly within 24 h (P < 0.001) and decreased from 24 to 60 hpi. The expression levels of IRF3 and p-IRF3 peaked at 24 hpi (P < 0.001) and decreased gradually from 24 to 60 hpi. However, the expression levels of JEV proteins showed no significant change at 24 and 36 hpi but were markedly elevated at 48 and 60 hpi. Interference with the expression of the RIG-1 protein in BV2 cells resulted in a dramatic increase in the expression of the anti-apoptotic protein Bcl-2 (P < 0.05), whereas the pro-apoptotic protein Bax, cleaved caspase-9, and especially cleaved caspase-3 were downregulated (P < 0.05), and viral protein expression was notably reduced (P < 0.05). These results indicate that JEV induces apoptosis through mitochondrial-dependent apoptosis pathways, interfering with the expression of RIG-1 in BV2 cells can inhibit viral replication and inhibit apoptosis.

Ginsenoside 24-OH-PD from red ginseng inhibits acute T-lymphocytic leukaemia by activating the mitochondrial pathway.

Ginsenoside 24-hydroxy-ginsengdiol (24-OH-PD), extracted from red ginseng, is a novel diol-type ginsenoside, strongly inhibits the growth of human T-cell acute lymphoblastic leukaemia (T-ALL) CCRF-CEM cells. Our research aimed at investigating the mechanism underlying this inhibition. Cell viability was determined using the cell counting kit-8 (CCK-8) assay, and NOD/SCID mice bearing CCRF-CEM cells were used to verify the therapeutic effect of 24-OH-PD on T-ALL in vivo. We equally analysed pathways related to 24-OH-PD in CCRF-CEM cells using RNA-Seq analysis. Cell apoptosis, reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), and mitochondrial permeability transition pore (mPTP) levels were detected by flow cytometry. The activity of caspase3 and caspase9 was detected by enzyme activity detection kits. The expression levels of apoptosis-related proteins and mRNA were determined through western blotting and quantitative reverse-transcription PCR assays (qRT-PCR). CCK-8 assay and animal xenograft experiments confirmed that 24-OH-PD significantly inhibited T-ALL in a dose-dependent manner, both in vivo and in vitro. RNA-Seq results suggest that mitochondria-mediated apoptosis pathway plays an important role in this process. Furthermore, intracellular ROS levels increased, mPTP opened, and ΔΨm decreased following 24-OH-PD treatment. Pretreatment with the antioxidant, NAC, reversed the effects of 24-OH-PD on apoptosis and ROS generation. Moreover, 24-OH-PD treatment increased the expression of Bax and caspase family members, thereby releasing cytochrome c (Cytc) and inducing apoptosis. Our findings showed that, 24-OH-PD induces apoptosis in CCRF-CEM cells by activating the mitochondrial-dependent apoptosis pathway through ROS accumulation. This inhibitory effect implies that 24-OH-PD could be further developed as treatment of T-ALL.

Novel 4-Amino-Quinazoline moieties ligated Platinum(IV) prodrugs overcome cisplatin resistance in EGFRWT human lung cancer

Developing bioactive axial ligands ligated platinum(IV) complexes with advantages over monotherapy and drug combinations is an efficient strategy to ameliorate the clinical defects of platinum(II) drugs. In this article, a series of 4-amino-quinazoline moieties (privileged pharmacophores of well-studied EGFR inhhibitors) ligated platinum(IV) were synthesized and evaluated for their anticancer activities. Among the complex, 17b demonstrated higher cytotoxicity against the tested lung cancer cells (including CDDP-resistant A549/CDDP cells) while lower cytotoxicity toward human normal cells than Oxaliplatin (Oxa) or cisplatin (CDDP). Mechanistic investigation demonstrated that the enhanced intracellular uptake of 17b efficiently elevated the of reactive oxygen species levels by 6.1 times more than Oxa. Detailed mechanisms of overcoming CDDP resistance revealed that 17b significantly induced apoptosis via inducing severe DNA damage, disturbing mitochondrial transmembrane potentials, efficiently disturbing EGFR-PI3K-Akt signaling transduction and activating a mitochondria-dependent apoptosis pathway. Besides, 17b significantly inhibited migration and invasion in A549/CDDP cells. In vivo tests exhibited that 17b obtained superior antitumor effect and attenuated systemic toxicity in A549/CDDP xenografts. All these results emphasized that the antitumor action of 17b differed from that of.classical platinum(II) drugs and provided a novel practical method to overcome CDDP resistance in lung cancer.

PINK1/Parkin-mediated mitophagy inhibits osteoblast apoptosis induced by advanced oxidation protein products

Osteoblast apoptosis plays an important role in age-related bone loss and osteoporosis. Our previous study revealed that advanced oxidation protein products (AOPPs) could induce nicotinamide adenine dinucleotide phosphate oxidase (NOX)-derived reactive oxygen species (ROS) production, cause mitochondrial membrane potential (ΔΨm) depolarization, trigger the mitochondria-dependent intrinsic apoptosis pathway, and lead to osteoblast apoptosis and ultimately osteopenia and bone microstructural destruction. In this study, we found that AOPPs also induced mitochondrial ROS (mtROS) generation in osteoblastic MC3T3-E1 cells, which was closely related to NOX-derived ROS, and aggravated the oxidative stress condition, thereby further promoting apoptosis. Removing excessive ROS and damaged mitochondria is the key factor in reversing AOPP-induced apoptosis. Here, by in vitro studies, we showed that rapamycin further activated PINK1/Parkin-mediated mitophagy in AOPP-stimulated MC3T3-E1 cells and significantly alleviated AOPP-induced cell apoptosis by eliminating ROS and damaged mitochondria. Our in vivo studies revealed that PINK1/Parkin-mediated mitophagy could decrease the plasma AOPP concentration and inhibit AOPP-induced osteoblast apoptosis, thus ameliorating AOPP accumulation-related bone loss, bone microstructural destruction and bone mineral density (BMD) loss. Together, our study indicated that therapeutic strategies aimed at upregulating osteoblast mitophagy and preserving mitochondrial function might have potential for treating age-related osteoporosis.

Eucalyptol antagonized the apoptosis and immune dysfunction of grass carp hepatocytes induced by tetrabromobisphenol A by regulating ROS/ASK1/JNK pathway.

Tetrabromobisphenol A (TBBPA) is a common environmental pollutant which has multi-organ toxicity to mammals. Eucalyptol (EUC) has super antioxidant biological activity. However, in this experimental study, we probed into the mechanism of toxic of TBBPA exposure on Grass carp hepatocytes (L8824 cells) and the antagonistic impact of EUC on TBBPA. We treated L8824 cells with 8μg/ml TBBPA and/or 20 μM EUC for 24 h in this test research. The experiment results suggested that TBBPA exposure induced elevated levels of reactive oxygen species (ROS), led to oxidative stress, decreased SOD and CAT activities, decreased GSH and T-AOC contents, exacerbated MDA accumulation, activated ASK1/JNK signaling pathway, and further increased the contents of mitochondrial dependent apoptosis pathway related indicators (Cyt-C, Bax, Caspase 9, Caspase 3), while Bcl-2 expression decreased. In addition, TBBPA exposure induced increased expression of TNF-α, IL-6, IL-1β, and decreased expression of IL-2, IFN-γ, Hepcidin, β-defensin, LEAP2. The oxidative stress level, ASK1/JNK signal pathway expression level, apoptosis ratio and cellular immune function of cells exposed to EUC alone did not change significantly. Combined exposure of TBBPA and EUC significantly reduced the proportion of apoptosis and restored cellular immune function. Therefore, these results suggest that EUC can effectively antagonize TBBPA-induced apoptosis and immune dysfunction of L8824 cells by regulating ROS/ASK1/JNK signaling pathway.

The cytoprotection of milk-derived MFG-E8 on mitochondria-injured L6 cell via mediation of Akt/bcl-2/bax-caspase-3 signaling pathway

Mitochondria-dependent myoblast apoptosis induced by oxidative stress and decrease in successful protein synthesis play a crucial role in loss of muscle mass and functionality further to result in sarcopenia. Here, we investigated the relationship between milk fat globule-EGF factor Ⅷ (MFG-E8) and mitochondrial-dependent apoptosis pathway. MFG-E8 exert cytoprotection through increasing L6 cells survival/apoptotic ratio, increasing mitochondrial membrane potential and regulating S and G2/M phases. By observing cell ultrastructure, MFG-E8 improved mitochondrial homeostasis mainly through decreasing cytochrome-c release, expression of caspase-9 and caspase-3, mitochondrial vacuolation and mitophagy thereby inhibiting cell apoptosis. From molecular perspective, MFG-E8 repaired mitochondria fragmentation by increasing mitochondrial DNA replication and regulated expression of key mitochondrial-apoptotic factors (upregulation: B-cell lymphoma-2 like 1 (bcl2l1), bcl2l2, cyclooxygenase-1 and mitochondrial uncoupling protein-2; Downregulation: p21 and p53) further to improve mitochondrial function and inhibit apoptosis. Moreover, MFG-E8 inhibited mitochondrial-dependent apoptosis via Akt/bcl-2/bax/caspase-3 signaling cascades. Taken together, our research provided a promising approach for deep exploration of MFG-E8 on cytoprotection against mitochondrial injury and mitochondrial-mediated apoptosis and application of anti-apoptosis in alleviating sarcopenia.

Arctigenin induces caspase-dependent apoptosis in FaDu human pharyngeal carcinoma cells.

The present study was carried out to investigate the effect of Arctigenin on cell growth and the mechanism of cell death elicited by Arctigenin were examined in FaDu human pharyngeal carcinoma cells. To determine the apoptotic activity of Arctigenin in FaDu human pharyngeal carcinoma cells, cell viability assay, DAPI staining, caspase activation analysis, and immunoblotting were performed. Arctigenin inhibited the growth of cells in a dose-dependent manner and induced nuclear condensation and fragmentation. Arctigenin-treated cells showed caspase-3/7 activation and increased apoptosis versus control cells. FasL, a death ligand associated with extrinsic apoptotic signaling pathways, was up-regulated by Arctigenin treatment. Moreover, caspase-8, a part of the extrinsic apoptotic pathway, was activated by Arctigenin treatments. Expressions of anti-apoptotic factors such as Bcl-2 and Bcl-xL, components of the mitochondria-dependent intrinsic apoptosis pathway, significantly decreased following Arctigenin treatment. The expressions of pro-apoptotic factors such as BAX, BAD and caspase-9, and tumor suppressor -53 increased by Arctigenin treatments. In addition, Arctigenin activated caspase-3 and poly (ADP-ribose) polymerase (PARP) induced cell death. Arctigenin also inhibited the proliferation of FaDu cells by the suppression of p38, NF-κB, and Akt signaling pathways. These results suggest that Arctigenin may inhibit cell proliferation and induce apoptotic cell death in FaDu human pharyngeal carcinoma cells through both the mitochondria-mediated intrinsic pathway and the death receptor-mediated extrinsic pathway.

Novel combretastatin A-4 derivative containing aminophosphonates as dual inhibitors of tubulin and matrix metalloproteinases for lung cancer treatment

Here, sixteen novel conjugates containing tubulin inhibitor and matrix metalloproteinase inhibitor was synthesized together with their activity evaluated. Among them, 9e exhibited the most potent activity against various human cancer cells (IC50 values was 0.19–0.42 μM) as well as multidrug-resistant tumor cells (A549/CDDP and MCF-7/DOX) and also showed significantly lower cytotoxic activity toward human normal liver cells LO2 in comparison with that of CA-4. Interestingly, 9e not only strongly inhibited tubulin polymerization, and induced cell apoptosis and cell cycle arrest in G2/M stage, but also remarkably displayed inhibition of cell migration against A549 cells in vitro, and exhibited a moderate activity toward MMP-2, MMP-3 and MMP-9, respectively. Moreover, the significant down-regulation in the levels of Bcl-2 protein and up-regulated levels of proteins, such as Bax, p53 and caspase-3, indicated that 9e can induce apoptosis via mitochondria-dependent apoptosis pathway. Additionally, 9e can also cause ER stress demonstrating as up-regulation express of proteins (CHOP, p-eIF2a, and p-PERK). Importantly, 9e displayed significant in vivo antitumor efficacy in A549 xenograft models without inducing apparent systemic toxicity. Collectively, this work indicated that compound 9e, a dual MMPs and tubulin inhibitor, is a novel and promising agent for cancer therapy.

The propofol-induced mitochondrial damage in fetal rat hippocampal neurons via the AMPK/P53 signaling pathway.

Propofol is a commonly used general anesthetic that may cause neuronal damage, especially in infants and young children. Mitochondria play an essential role in cellular metabolism and signal transduction. Propofol may cause neurotoxicity by inhibiting mitochondrial function, but the mechanism by this which occurs remains unclear. First, the primary rat hippocampal neurons were cultured for 7 days in vitro. The neurons were incubated with propofol at different times or different concentrations, and then the adenosine triphosphate (ATP), reactive oxygen species (ROS), mitochondrial membrane potential, and apoptosis-related proteins were analyzed. Based on the results of the 1st phase, the neurons were then incubated with propofol (100 µM) or corresponding reagents, including 5-aminoimidazole-4-carboxamide ribonucleotide, tenovin-1, and pifithrin-α. Subsequently, the ATP, ROS, mitochondrial membrane potential, phospho-adenosine 5'-monophosphate-activated protein kinase (p-AMPK), protein 53 (p53), and related apoptosis proteins were analyzed. Higher propofol concentrations or longer incubation times were associated with more pronounced decreases in ATP, B-cell lymphoma 2 (Bcl-2), and mitochondrial membrane potential, and more pronounced increases in ROS, BCL2-associated X (Bax), Cytochrome C (CytC), and cleaved caspase-9. Additionally, after incubation with propofol (100 µM), neuronal Bcl-2, p-AMPK, ATP, and mitochondrial membrane potential were downregulated, and ROS, p53, CytC, Bax, cleaved caspase-3, and cleaved caspase-9 were upregulated. AMPK activators or p53 inhibitors reversed the above-mentioned changes. Propofol (100 µM)-induced mitochondrial damage in fetal rat hippocampal neurons may be mediated by the AMPK/p53 signaling pathway. Propofol (100 µM) was shown to inhibit the activity of AMPK in neurons, upregulate the expression of p53, and then activate the mitochondrial-dependent apoptosis pathway, which may lead to neuronal apoptosis.