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Gasdermin E (GSDME), a member of the gasdermin protein family, is associated with post-lingual hearing loss. All GSDME pathogenic mutations lead to skipping exon 8; however, the molecular mechanisms underlying hearing loss caused by GSDME mutants remain unclear. GSDME was recently identified as one of the mediators of programmed cell death, including apoptosis and pyroptosis. Therefore, in this study, we injected mice with GSDME mutant (MT) and examined the expression levels to assess its effect on hearing impairment. We observed loss of hair cells in the organ of Corti and spiral ganglion neurons. Further, the N-terminal release from the GSDME mutant in HEI-OC1 cells caused pyroptosis, characterized by cell swelling and rupture of the plasma membrane, releasing lactate dehydrogenase and cytokines such as interleukin-1β. We also observed that the N-terminal release from GSDME mutants could permeabilize the mitochondrial membrane, releasing cytochromes and activating the mitochondrial apoptotic pathway, thereby generating possible positive feedback on the cleavage of GSDME. Furthermore, we found that treatment with disulfiram or dimethyl fumarate might inhibit pyroptosis and apoptosis by inhibiting the release of GSDME-N from GSDME mutants. In conclusion, this study elucidated the molecular mechanism associated with hearing loss caused by GSDME gene mutations, offering novel insights for potential treatment strategies., (© 2024. The Author(s).)

Aim: To explore the effect of the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (Aza) on early renal injury. Materials & methods: Cell damage and inflammation are features of early renal injury. The apoptosis and inflammation in hypoxia/reoxygenation (H/R)-induced human proximal tubular epithelial cells (HK-2) and ischemia-reperfusion kidney were studied, and expression of the protein klotho was investigated. Results: Aza induced HK-2 apoptosis in a dose-dependent manner, but low-dose Aza attenuated the apoptosis and inflammation in H/R-induced HK-2 cells and ischemia-reperfusion kidney. Low-dose Aza ameliorated renal function in mice with renal ischemia-reperfusion injury. Meanwhile, low-dose Aza upregulated klotho expression in H/R-induced HK-2 cells and ischemia-reperfusion kidney. Klotho knockdown abrogated the effects of low-dose Aza on apoptosis and inflammation. Conclusion: Low-dose Aza protects against renal early injury by increasing klotho expression.

In this study, 10 metabolites were obtained by collecting and extracting fecal samples after oral administration of panaxadiol (PD). Of these 10 metabolites, M7 (3β,21β,22α-hydroxy-24-norolean-12-ene), M8 (21β,22α-hydroxy-24-norolean-12-ene-3-one), M9 (3β,30α-hydroxy-24-norolean-22,30-epoxy-12-ene), and M10 (3β,21β-hydroxy-24-norolean-12-ene) were new compounds. MTT screening of the isolated compounds revealed that the inhibitions of cancer cells by M2, M4, M7, M8, and M10 were significantly stronger than that by the mother drug M0, with the activity of M2 being the most significant. Further, we investigated the anticancer mechanism of M2. The results showed that M2 significantly increased the level of ROS in cells; regulated the expressions of Bax, Bcl-2, and Cyt-C through the mitochondrial pathway; triggered the caspase cascade; and induced apoptosis. M2 could also induce G1 phase arrest and significantly regulate cell cycle-related proteins. In conclusion, the experimental results provide data for further study on the metabolic mechanism of PD in vivo and the potential of developing new anti-cancer drugs.

Spag6 encodes an axoneme central apparatus protein that is required for normal flagellar and cilia motility. Recent findings suggest that Spag6 plays a role in hearing and planar cell polarity (PCP) in the cochlea of the inner ear. However, a role for Spag6 in the vestibule has not yet been explored. In the present study, the function of Spag6 in the vestibule of the inner ear was examined using Spag6-deficient mice. Our results demonstrate a vestibular disorder in the Spag6 mutants, associated with abnormal ultrastructures of vestibular hair cells and Scarpa's ganglion cells, including swollen stereocilia, decreased crista in mitochondria and swollen Scarpa's ganglion cells. Immunostaining data suggests existence of caspase-dependent apoptosis in vestibular sensory epithelium and Scarpa's ganglion cells. Our observations reveal new functions for Spag6 in vestibular function and apoptosis in the mouse vestibule., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Copyright © 2021 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Pneumonia is one of the common respiratory diseases in pediatrics. Ubiquitin-specific protease 14 (USP14) contributes the progress of inflammation-associated diseases. Poly (ADP-ribose) polymerase-1 (PARP-1) involves in the signal transduction of inflammatory pulmonary disease. This study aims to identify the precise function and elaborate the regulatory mechanism of USP14/PARP-1 in the injury of lung epithelial cells. Human lung epithelial BEAS-2B cells received lipopolysaccharide (LPS) (0, 1, 5, and 10 mg/L) treatment for 16 h, establishing in vitro pneumonia model. USP14 protein and mRNA levels in LPS-injured lung epithelial cells were separately assessed using western blot and RT-qPCR analysis. Lung epithelial cells were transfected with siRNA-USP14 or OV-USP14 to perform gain- or loss-of-function experiments. CCK-8 assay was applied to assess cell viability. TUNEL staining and western blot analysis were adopted to determine cell apoptosis. In addition, release of inflammatory cytokines and nitric oxide (NO) was detected using the commercial kits. Meanwhile, PARP-1 protein levels in LPS-injured lung epithelial cells were detected by performing western blot assay. Moreover, Co-IP assay was utilized for detection of the interaction between USP14 and PARP-1. The regulatory effects of PARP-1 on USP14 function in LPS-injured lung epithelial cells were also investigated. LPS dose-dependently reduced viability of lung epithelial cells and elevated USP14 protein. USP14 combined with PARP-1 and increased PARP-1 expression. USP14 elevation exacerbated inflammatory injury and boosted the apoptosis of LPS-injured lung epithelial cells, which was reversed upon downregulation of PARP-1. To sum up, USP14 promotion exacerbated inflammatory injury and boosted the apoptosis of LPS-injured lung epithelial cells by upregulating PARP-1 expression. These findings may represent a therapeutic target for clinical intervention in pneumonia., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In this study, piperazine groups were introduced into ginsenoside to enhance its ability to induce Reactive Oxygen Species (ROS) production and apoptosis in cancer cells. In total, 27 ginsenoside piperazine derivatives were synthesized and tested for their anti-proliferative activity in cancer cell lines by MTT assay. The results showed that compounds 4a, 4g, 4f, 4i, 5g, 5i, 6a, 6g, 6f and 6i had significant inhibitory effects on cancer cell growth. Compound 6g showed the strongest anti-proliferative effect on PC-3 cells with an IC 50 of 1.98 ± 0.34 μM. Compound 6g could also induce G1-phase arrest and apoptosis in PC-3 cells, with apoptosis rates of 8.1%, 41% and 56.1% observed at 5, 10 and 20 μM, respectively. Compound 6g also significantly enhanced the intracellular fluorescence of ROS sensitive substrates, with a fluorescence intensity ratio of 23.1% observed in treated cells, indicative of ROS production. Following N-acetylcysteine treatment, apoptotic rates of the cancer cell lines decreased from 38.9% to 7.3%, and the expression of Cl-PARP, Cl-Caspase-3 and Cl-Caspase-9 also decreased, confirming that compound 6g induced apoptosis through ROS induction. Compound 6g also stimulated the translocation of Bax from the cytoplasm to the mitochondria, which enhanced Cytochrome C (Cyt C) release, and increased the expression of the apoptotic markers Cl-PARP, Cl-Caspase-3, and Cl-Caspase-9 in PC-3 cells. Taken together, these data reveal the anti-cancer effects of compound 6g that enhance ROS production, and then induce apoptosis through mitochondrial pathway., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Synaptic dysfunction and neuronal loss are related to cognitive impairment of Alzheimer's disease. Recent evidence indicates that regulating the phosphatidylinositol 3-Kinase (PI3K)/AKT/GSK-3β pathway is a therapeutic strategy for improving synaptic plasticity in Alzheimer's disease. Here, we investigated "olfactory three-needle" effects on synaptic function and the PI3K/AKT/GSK-3β signaling pathway in β-amyloid 1-42 (Aβ 1-42 )-induced Alzheimer's disease rats. A three-needle olfactory bulb insertion for 28 days alleviated Aβ 1-42 -induced Alzheimer's disease rats' cognitive impairment as assessed by performance in the Morris water maze test. Furthermore, the three-needle electrode inhibited neuro-apoptosis and neuro-inflammation. It significantly upregulated the protein expression of postsynaptic density protein 95, synaptophysin, and GAP43, indicating a protective effect on hippocampal synaptic plasticity. Additionally, the activation level of PI3K/AKT signaling and the phosphorylation inactivation of GSK-3β were significantly enhanced by the "olfactory three-needle". Our findings suggested that the three-needle acupuncture is a potential alternative to improve synaptic plasticity and neuronal survival of Alzheimer's disease brain in rodents., Competing Interests: The authors declare no competing interests., (© 2021 The Authors. Published by IMR Press.)

Background: Leaves of the natural plant lotus are used in traditional Chinese medicine and tea production. They are rich in flavonoids., Methods: In this study, lotus leaf flavonoids (LLF) were applied to human lung cancer A549 cells and human small cell lung cancer cells H446 in vitro to verify the effect of LLF on apoptosis in these cells through the ROS/p38 MAPK pathway., Results: LLF had no toxic effect on normal cells at concentrations up to 500 µg/mL, but could significantly inhibit the proliferation of A549 cells and H446 cells. Flow cytometry showed that LLF could induce growth in A549 cells. We also found that LLF could increase ROS and MDA levels, and decrease SOD activity in A549 cells. Furthermore, qRT-PCR and western blot analyses showed that LLF could upregulate the expression of p38 MAPK (p-p38 MAPK), caspase-3, caspase-9, cleaved caspase-3, cleaved caspase-9 and Bax and downregulate the expression of Cu/Zn SOD, CAT, Nrf2, NQO1, HO-1, and Bcl-2 in A549 cells. Results of HPLC showed that LLF mainly contain five active substances: kaempferitrin, hyperoside, astragalin, phloridzin, and quercetin. The apoptosis-inducing effect of LLF on A549 cells came from these naturally active compounds., Conclusions: We have shown in this study that LLF is a bioactive substance that can induce apoptosis in A549 cells in vitro, and merits further research and development.

The present study aimed to investigate the effect of the long non-coding RNA antisense non-coding RNA in the INK4 locus (lnc-ANRIL) knockdown on apoptosis, neurite outgrowth and inflammation based on a PC12 cellular Alzheimer's disease (AD) model. A cellular AD model was constructed by treating nerve growth factor stimulated PC12 cells with amyloid β (Aβ) 1-42 and then control knockdown plasmid and lnc-ANRIL knockdown plasmid were transfected in the PC12 cellular AD model as the KD- negative control (NC) group or the AD-ANRIL group respectively. Apoptosis, neurite outgrowth, pro-inflammatory cytokines and microRNA (miR)-125a were assessed. Rescue experiments were conducted by transfecting lnc-ANRIL knockdown plasmid and lnc-ANRIL knockdown plasmid and miR-125a inhibitor in the PC12 cellular AD model as the KD-ANRIL group or KD-ANRIL + KD-miR-125a group respectively. Following transfection, cell apoptosis deccreased while neurite outgrowth increased in the KD-ANRIL group compared with the KD-NC group (all P<0.01). Concerning inflammation, tumor necrosis factor-α (TNF-α) and interleukin (IL)-1β, IL-6 and IL-17 were decreased in the KD-ANRIL group compared with the KD-NC group (all P<0.01). miR-125a was negatively regulated by lnc-ANRIL and therefore rescue experiments were subsequently conducted. In the rescue experiments, cell apoptosis was increased while total neurite outgrowth was inhibited in the KD-ANRIL + KD-miR-125a group compared with the KD-ANRIL group (all P<0.01), and TNF-α, IL-1β, IL-6 and IL-17 were increased in the KD-ANRIL + KD-miR-125a group compared with the KD-ANRIL group (all P<0.01). A luciferase reporter assay demonstrated that lnc-ANRIL directly bound miR-125a. lnc-ANRIL knockdown suppressed cell apoptosis and inflammation while promoting neurite outgrowth via binding of miR-125a in AD.

Atherosclerosis (AS) is a common vascular disease, which can cause apoptosis of vascular endothelial cells. Notoginsenoside R1 (NGR1) is considered an anti-AS drug. MicroRNAs (miRNAs) are believed to play a vital role in cell apoptosis and angiogenesis. This study aimed to explore the mechanism of NGR1 for treating AS through miRNAs. Flow cytometry was used to detect the apoptosis rate. The levels of inflammatory cytokines interleukin (IL)-6 and IL-1β were detected using ELISA. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were measured using corresponding assay kits. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was performed to detect miR-221-3p expression. Dual-luciferase reporter and RNA immunoprecipitation assays were carried out to examine the relationship between miR-221-3p and toll-like receptors 4 (TLR4). Also, western blot analysis was performed to determine the levels of TLR4 and nuclear factor kappa B (NF-κB) signaling pathway-related proteins. Oxidized low-density lipoprotein (ox-LDL) induced human umbilical vein endothelial cells (HUVECs) apoptosis, inflammation, and oxidative stress. NGR1 alleviated the negative effect of ox-LDL through promoting the expression of miR-221-3p in HUVECs. TLR4 was a target of miR-221-3p, and its overexpression could reverse the inhibition effects of miR-221-3p on apoptosis, inflammation, and oxidative stress. NGR1 improved miR-221-3p expression to inhibit the activation of the TLR4/NF-κB pathway in ox-LDL-treated HUVECs. NGR1 decreased ox-LDL-induced HUVECs apoptosis, inflammation, and oxidative stress through increasing miR-221-3p expression, thereby inhibiting the activation of the TLR4/NF-κB pathway. This study of the mechanism of NGR1 provided a more theoretical basis for the treatment of AS.

Hepatocyte nuclear factor-1β (Hnf1β) is associated with early embryogenesis failure, renal cysts, and/or diabetes. However, factors regulating Hnf1β expression in metanephric mesenchyme cells remain poorly understood. Here, we analyzed the modulation relationship of Hnf1β and miR-194 in mouse metanephric mesenchyme (MM) cells. Bioinformatics analysis, luciferase assay and semi-quantitative real-time (qPCR), western blotting, 5-ethynyl-2'-deoxyuridine cell proliferation assay, wound healing assay, and flow cytometry were employed to detect the function of miR-194 by targeting on Hnf1β in mouse MM cells. Bioinformatic prediction revealed one conserved binding site (CAGTATT) of miR-194 on Hnf1β 3'-UTR and luciferase reporter assay suggested that this is an effective target site of miR-194, and mutating CAGTATT with CGTACTT had no effects on luciferase activity compared with control. Overexpression of miR-194 decreased Hnf1β mRNA and protein level in mouse MM cells. In addition, miR-194-decreased cell proliferation and miR-194-promoted cell apoptosis and migration were reversed by overexpression of Hnf1β coding region. In addition, Hnf1β-upregulated genes were decreased in miR-194 overexpression cells and rescued in miR-194 and Hnf1β CDS region co-overexpression cells. Our findings explored one new regulator of Hnf1β and revealed the function of their regulation in cell proliferation, migration, and apoptosis in mouse metanephric mesenchyme cells. For strict regulation of Hnf1β in kidney development, these findings provide theoretical guidance for kidney development study and kidney disease therapy.

Background: Cancer cells avidly consume glucose and convert it to lactate, resulting in a low pyruvate level. This phenomenon is known as the Warburg effect, and is important for cell proliferation. Although cMyc has often been described as an oncoprotein that preferentially contributes to the Warburg effect and tumor proliferation, mechanisms of action remain unclear. Histone deacetylase 3 (HDAC3) regulates gene expression by removing acetyl groups from lysine residues, as well as has an oncogenic role in apoptosis and contributes to the proliferation of many cancer cells including cholangiocarcinoma (CCA). HDAC inhibitors display antitumor activity in many cancer cell lines. Cancer cells maintain low levels of pyruvate to prevent inhibition of HDAC but the mechanisms remain elusive. The purpose of our study was to explore the role of cMyc in regulating pyruvate metabolism, as well as to investigate whether the inhibitory effect of pyruvate on HDAC3 could hold promise in the treatment of cancer cells., Methods: We studied pyruvate levels in CCA cell lines using metabolite analysis, and analyzed the relationship of pyruvate levels and cell proliferation with cell viability analysis. We cultivated CCA cell lines with high or low levels of pyruvate, and then analyzed the protein levels of HDAC3 and apoptotic markers via Western Blotting. We then explored the reasons of low levels of pyruvate by using seahorse analysis and 13 C 6 metabolites tracing analysis, and then confirmed the results using patient tissue protein samples through Western Blotting. Bioinformatics analysis and transfection assay were used to confirm the upstream target of the low levels of pyruvate status in CCA. The regulation of cMyc by HDAC3 was studied through immunoprecipitation and Western Blotting., Results: We confirmed downregulated pyruvate levels in CCA, and defined that high pyruvate levels correlated with reduced cell proliferation levels. Downregulated pyruvate levels decreased the inhibition to HDAC3 and consequently protected CCA cells from apoptosis. Synergistically upregulated LDHA, PKM2 levels resulted in low levels of pyruvate, as well as poor patient survival. We also found that low levels of pyruvate contributed to proliferation of CCA cells and confirmed that the upstream target is cMyc. Conversely, high activity of HDAC3 stabilized cMyc protein by preferential deacetylating cMyc at K323 site, which further contributed to the low pyruvate levels. Finally, this creates a positive feedback loop that maintained the low levels of pyruvate and promoted CCA proliferation., Conclusions: Collectively, our findings identify a role for promoting the low pyruvate levels regulated by c-Myc, and its dynamic acetylation in cancer cell proliferation. These targets, as markers for predicting tumor proliferation in patients undergoing clinical treatments, could pave the way towards personalized therapies.

Cisplatin is an anti-cancer drug that causes oxotoxic side effects such as impairment of inner ear function and hearing loss. We aimed to investigate the effects of allicin against cisplatin-induced stria vascularis damage in mice, and to clarify the mechanism underlying the protective effects of allicin against ototoxicity. Stria vascularis injury was induced in mice by intraperitoneal injection of cisplatin, which was significantly prevented by pretreatment with allicin. Allicin not only reduced cisplatin-activated expression of cleaved caspase-3 in marginal cells, PVM/Ms (perivascular resident macrophage-like melanocytes), and basal cells of the stria vascularis, but also decreased the expression of poly(ADP-ribose) polymerase-1 (PARP-1) and apoptosis-inducing factor (AIF) nuclear translocation in the stria vascularis cells. Our results demonstrate that allicin plays an effective role in protecting stria vascularis injury induced by cisplatin by inhibiting caspase-dependent, as well as caspase-independent PARP-1-AIF-mediated apoptotic pathways. Therefore, allicin may be useful in preventing cisplatin-induced ototoxicity., (© 2019 S. Karger AG, Basel.)

Objective: In order to investigate the effect of secretagogin (SCGN) on colorectal cancer (CRC) cells apoptosis, invasion and migration in vitro., Methods: Expression of SCGN in CRC tissues and the paired adjacent non-tumorous tissues (n = 36) and four human CRC cell lines (HT29, HCT116, SW480 and SW620) were detected. SW480 cells were transfected with the SCGN overexpression plasmid (eGFP-SCGN), si-SCGN-773, and the corresponding negative controls (NCs). Then, cell-cycle distribution, cell apoptosis, migration, invasion and expression of apoptosis- and metastasis-related proteins were detected., Results: SCGN was significantly downregulated in CRC tissues as compared with the adjacent non-tumorous tissues. The expression of SCGN in HT29 and SW480 cells were lower than those in HT116 and SW620 cells. We transfected SW480 cells with SCGN overexpression plasmid eGFP-SCGN and found the increased cell apoptosis, with cell arresting at G0/G1 phase. SW480 cells with SCGN overexpression showed wider wound width and fewer invaded cells than control and blank cells, with upregulated Bax, cleaved Caspase 3 and E-cadherin, and downregulated Bcl-2 and Vimentin. We also transfected SW480 cells with si-SCGN-773 and found si-SCGN increased cell migration and invasion, but did not affect cell apoptosis and expression of related proteins., Conclusion: We concluded that the overexpression of SCGN in SW480 cells promoted cell apoptosis and inhibited cell migration and invasion., (Copyright © 2018. Published by Elsevier Masson SAS.)

Mammalian Sperm Associated Antigen 6 (SPAG6) is the orthologue of Chlamydomonas PF16, a protein localized in the axoneme central apparatus. Recent studies showed that Spag6 has a role in brain neuronal proliferation and differentiation. The mammalian spiral ganglion neurons (SGNs) are specialzed bipolar neurons in the inner ear. However, the role of SPAG6 in SGN has not been elucidated. Therefore, We hypothesized that a Spag6 knockout would affect the development and function of SGNs. We utilized Spag6-deficient mice and SGN explants to define the role of SPAG6. On postnatal day 30 (P30) mutant mice had lower SGN density compared to their wild-type littermates, and more apoptosis was evident in the mutants. Increased Bax expression, a disturbed distribution of cytochrome c, and cleaved caspase-3 positive staining indicated that increased apoptosis involved a mitochondrial pathway. Transmission electron microscopy revealed abnormalities in the ultrastructure of mutant SGNs as early as P7. In vitro, lack of SPAG6 affected the growth of neurites and growth cones. Additionally, SPAG6 deficiency decreased synapse density in SGN explants. Finally, Spag6 mutant SGNs were more sensitive to the microtubule stabilizing agent, paclitaxel. These findings suggest that Spag6 plays a crucial role in SGN development and function.

Previous studies have suggested that estradiol can reduce the ischemia/reperfusion (I/R) injury in skin flaps. However, the mechanism, particularly the signal pathways involved in this protective effect are not well established. In the current study, an I/R injury model was established in rats to explore the connection between estradiol protection during I/R injury and extracellular signal‑regulated kinase (ERK) signaling. Healthy male Wistar rats were divided into five groups (n=10): Control group (group I), I/R group (group II), saline group (group III), estradiol group (group IV) and inhibitor (PD‑98059) group (group V). The survival rate of the flap was compared between groups, morphological changes were observed by hematoxylin and eosin staining of sections, and terminal deoxynucleotidyl transferase dUTP nick end labeling was performed to identify apoptotic cells and determine the apoptotic index. To further investigate the mechanism, western blot analysis was performed to assess the protein level of ERK1/2, phospho‑ERK1/2, and mitogen‑activated protein kinase phosphatase 1 (MKP‑1). The results of the present study demonstrated that estradiol therapy can reduce I/R injury and decrease the apoptosis index in an axial skin flap model. The inhibitor of the ERK pathway (PD‑98059) partially abolished the effects of estradiol, which involve the phosphatase enzyme MKP‑1. Taken together, the findings of the present study indicate that estradiol may act by reducing the expression of MKP‑1, mediating the expression/activation changes of the ERK pathway and subsequently reduce the level of apoptosis and the I/R injury the axial flap. Estrogen may be used to mitigate the adverse reaction caused by ischemia‑reperfusion injury and effectively improve the survival rate and survival quality of free skin flap and improve patient prognosis.

Cisplatin is an anticancer drug that causes the impairment of inner ear function as side effects, including hearing loss and balance dysfunction. The purpose of this study was to investigate the effects of allicin against cisplatin-induced vestibular dysfunction in mice and to make clear the mechanism underlying the protective effects of allicin on oto-vestibulotoxicity. Mice intraperitoneally injected with cisplatin exhibited vestibular dysfunction in swimming test, which agreed with impairment in vestibule. However, these impairments were significantly prevented by pre-treatment with allicin. Allicin markedly reduced cisplatin-activated expression of cleaved-caspase-3 in hair cells and vascular layer cells of utricule, saccule and ampulla, but also decreased AIF nuclear translocation of hair cells in utricule, saccule and ampulla. These results showed that allicin played an effective role in protecting vestibular dysfunction induced by cisplatin via inhibiting caspase-dependent and caspase-independent apoptotic pathways. Therefore, allicin may be useful in preventing oto-vestibulotoxicity mediated by cisplatin., (Copyright © 2017. Published by Elsevier B.V.)

Death-associated protein kinase-related apoptosis-inducing kinase-2 (DRAK2) is a serine/threonine kinase that plays a key role in a wide variety of cell death signaling pathways. Inhibition of DRAK2 was found to efficiently protect islet β-cells from apoptosis and hence DRAK2 inhibitors represent a promising therapeutic strategy for the treatment of diabetes. Only very few chemical entities targeting DRAK2 are currently known. We carried out a high throughput screening and identified compound 4 as a moderate DRAK2 inhibitor with an IC 50 value of 3.15 μM. Subsequent SAR studies of hit compound 4 led to the development of novel benzofuran-3(2H)-one series of DRAK2 inhibitors with improved potency and favorable selectivity profiles against 26 selected kinases. Importantly, most potent compounds 40 (IC 50  = 0.33 μM) and 41 (IC 50  = 0.25 μM) were found to protect islet β-cells from apoptosis in dose-dependent manners. These data support the notion that small molecule inhibitors of DRAK2 represents a promising strategy for the treatment of diabetes., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Decidualization of endometrial stromal cells is an important feature of implantation and pregnancy. The molecular mechanism underlying decidualization remains unclear, particularly regarding the microRNA (miRNA/miR) regulation of this process. The present study revealed the temporal and spatial distribution of mmu‑miR‑96 in the mouse uterus during early pregnancy by reverse transcription‑quantitative polymerase chain reaction and in situ hybridization. In addition, primary stromal cells were isolated from the mouse uterus and used to explore the role of mmu‑miR‑96 in decidualization. The results demonstrated that mmu‑miR‑96 was highly expressed in stromal cells during pregnancy, and was upregulated at implantation sites. In addition, mmu‑miR‑96 was strongly expressed during decidualization, which indicates that it may serve a role in the decidualization of stromal cells. Based on existing reports, mmu‑miR‑96 participates in apoptosis; therefore the present study investigated its effects on the apoptosis of primary endometrial stromal cells. The results indicated that overexpression of mmu‑miR‑96 may induce apoptosis of stromal cells. In further studies regarding the underlying mechanism, the target genes of mmu‑miR‑96 were screened by bioinformatics analysis, and it was confirmed that B‑cell lymphoma 2, an anti‑apoptotic gene, was the target of mmu‑miR‑96, as determined using a reporter gene assay. In conclusion, the present study suggested that mmu‑miR‑96 participates in the decidualization of endometrial stromal cells in mice, thereby serving a key role in pregnancy.

Timosaponin AIII (AIII), a steroidal saponin isolated from Anemarrhena asphodeloides Bge. Our study showed that AIII induced both apoptosis and autophagy, and autophagy inhibited apoptosis in A375S2 cells. Furtherly, this study was carried out to investigate what kind of cytokines plays an important role in this process. The results revealed that AIII induced apoptosis through activating c-Jun N-terminal protein kinase (JNK) or extracellular signal related kinase (ERK) signaling pathway and generating NO. However, JNK or ERK inhibited autophagy, while NO had no effect on autophagy. Therefore, JNK, ERK or NO regulates two programmed death processes in different ways. AIII did not show obvious cytotoxic effect on human peripheral blood mononuclear cells, which indicated that AIII has less side effects on normal cells, and could be considered as a leading compound for developing novel anticancer drug.

Infection by most viruses triggers apoptosis in host cells, and viruses manipulate this cell response to promote viral replication, virus spread, and cell killing. Porcine reproductive and respiratory syndrome virus (PRRSV) has been shown to induce apoptosis both in vitro and in vivo, while the regulatory roles of PRRSV-encoded products in apoptosis are not fully understood. In the present study, we first showed a biphasic apoptosis regulation by a highly pathogenic PRRSV strain JXwn06. It was indicated that PRRSV infection delays apoptosis at early infection but activates apoptosis at late infection in MARC-145 cells. In PRRSV-infected MARC-145 cells, procaspase-8, -9 and -12 were activated at late infection, demonstrating the involvements of death receptor pathway, mitochondrial pathway and endoplasmic reticulum (ER) stress pathway in inducing apoptosis. PRRSV was also shown to induce a similar apoptosis process in pulmonary alveolar macrophages (PAMs) with an early initiation. Next, the PRRSV-encoded apoptosis inducers were screened, indicating that the nonstructural protein (Nsp) 4 and Nsp10 of PRRSV are pro-apoptotic. In the presence of Nsp4, it was confirmed that procaspase-8, -9 and -12 were cleaved, and Nsp4 facilitates the cleavage of procaspase-9 by activating B-cell lymphoma 2 interacting mediator of cell death (Bim), a pro-apoptotic protein. In addition, Nsp4 was shown to induce the degradation of an anti-apoptotic protein, B-cell lymphoma-extra large (Bcl-xL). Nsp10 was shown to activate procaspase-8 and -9 but procaspase-12 and to upregulate the expression of BH3-only pro-apoptotic protein BH3 interacting-domain death agonist (Bid) and its active form, truncated Bid (tBid). Clearly, the participation of both activated caspase-8 and Bid is required for Nsp10-induced apoptosis, indicating a crosstalk between extrinsic- and mitochondria-dependent pathways. Together, our findings suggest that PRRSV infection regulates apoptosis in a two-phase manner and activates all three apoptotic pathways; the Nsp4 and Nsp10 of PRRSV function as apoptosis inducers with different molecular basis.

The potential interference of endocrine disrupting chemicals (EDCs) on aquatic animals and humans has drawn wide attention in recent years. Reports have shown that some organophosphorus pesticides were a kind of EDCs, but their effects on fish species are still under research. In present study, flow cytometry data of HEC-1B cell line showed that chlorpyrifos (CPF) could increase cell proliferation index like 17β-estradiol (E2), but the effect of CPF was weaker than of E2 in the same concentration. Moreover, CPF altered the expression pattern of estrogen-responsive gene VTG and ERα in zebrafish embryos. When exposed to CPF at various concentrations (0, 0.10, 0.25, 0.50, 0.75 and 1.00mg/L) for 48h during the embryo stage, compared with controls, the hatching rate of treated groups significantly increased at the same time and the hatching rate of embryos was proportional to CPF concentration. The mRNA expression levels of c-myc, cyclin D1, Bax and Bcl-2, which are closely related to cell proliferation and cell apoptosis, were disturbed by CPF in zebrafish embryos after exposure treated for 48h. In addition, acridine orange (AO) staining of zebrafish embryos showed that cell apoptosis was appeared in the 0.75, 1.00mg/L CPF treated groups. Taken together, the results obtained in the present study indicated that chlorpyrifos is estrogenic and alters embryonic hatching, cell proliferation and apoptosis in zebrafish., (Copyright © 2015. Published by Elsevier Ireland Ltd.)

Endoplasmic reticulum (ER) stress induced apoptosis plays a pivotal role in myocardial ischemia/reperfusion (I/R)-injury. Inhibiting ER stress is a major therapeutic target/strategy in treating cardiovascular diseases. Our previous studies revealed that lycopene exhibits great pharmacological potential in protecting against the I/R-injury in vitro and vivo, but whether attenuation of ER stress (and) or ER stress-induced apoptosis contributes to the effects remains unclear. In the present study, using neonatal mouse cardiomyocytes to establish an in vitro model of hypoxia/reoxygenation (H/R) to mimic myocardium I/R in vivo, we aimed to explore the hypothesis that lycopene could alleviate the ER stress and ER stress-induced apoptosis in H/R-injury. We observed that lycopene alleviated the H/R injury as revealed by improving cell viability and reducing apoptosis, suppressed reactive oxygen species (ROS) generation and improved the phosphorylated AMPK expression, attenuated ER stress as evidenced by decreasing the expression of GRP78, ATF6 mRNA, sXbp-1 mRNA, eIF2α mRNA and eIF2α phosphorylation, alleviated ER stress-induced apoptosis as manifested by reducing CHOP/GADD153 expression, the ratio of Bax/Bcl-2, caspase-12 and caspase-3 activity in H/R-treated cardiomyocytes. Thapsigargin (TG) is a potent ER stress inducer and used to elicit ER stress of cardiomyocytes. Our results showed that lycopene was able to prevent TG-induced ER stress as reflected by attenuating the protein expression of GRP78 and CHOP/GADD153 compared to TG group, significantly improve TG-caused a loss of cell viability and decrease apoptosis in TG-treated cardiomyocytes. These results suggest that the protective effects of lycopene on H/R-injury are, at least in part, through alleviating ER stress and ER stress-induced apoptosis in neonatal mouse cardiomyocytes.

Nonalcoholic fatty liver disease (NAFLD) has emerged as one of the most common chronic liver disease over the past decades. Endoplasmic reticulum stress (ERS) plays a pivotal role during the development of NAFLD. This study aims to analyze the potential role of protein disulfide isomerase A3 precursor (PDIA3), one of the ER chaperones, in free fatty acid-induced cell model of NAFLD. Human liver L02 cell line was treated with sodium palmitate for 24 hours, which developed severe intracellular lipid accumulation. The increased protein level of PDIA3 was detected via immunoblotting analysis in the fat loaded cell models of NAFLD. siRNA-mediated knockdown of PDIA3 in L02 cells not only increased the cellular lipid accumulation, but also exacerbated hepatocytes apoptosis induced by sodium palmitate. Further investigation revealed that knockdown of PDIA3 up-regulated protein expression of fatty acid synthase (FAS), a key enzyme involved in fatty acid synthesis. PDIA3 knockdown also up-regulated key molecules of ERS pathway, including glucose-regulated protein 78 (GRP78), phospho-PKR-like ER kinase (p-PERK), and C/EBP homologous protein (CHOP). Our results suggested that ER chaperone PDIA3 plays a pivotal role in FFA-induced hepatocyte steatosis and apoptosis.

Pigment epithelium-derived factor (PEDF) is a pleiotropic gene with anti-inflammatory, antioxidant and anti-angiogenic properties. However, recent reports about the effects of PEDF on cardiomyocytes are controversial, and it is not known whether and how PEDF acts to inhibit hypoxic or ischemic endothelial injury in the heart. In the present study, adult Sprague-Dawley rat models of acute myocardial infarction (AMI) were surgically established. PEDF-small interfering RNA (siRNA)-lentivirus (PEDF-RNAi-LV) or PEDF-LV was delivered into the myocardium along the infarct border to knockdown or overexpress PEDF, respectively. Vascular permeability, cardiomyocyte apoptosis, myocardial infarct size and animal cardiac function were analyzed. We also evaluated PEDF's effect on the suppression of the endothelial permeability and cardiomyocyte apoptosis under hypoxia in vitro. The results indicated that PEDF significantly suppressed the vascular permeability and inhibited hypoxia-induced endothelial permeability through PPARγ-dependent tight junction (TJ) production. PEDF protected cardiomyocytes against ischemia or hypoxia-induced cell apoptosis both in vivo and in vitro via preventing the activation of caspase-3. We also found that PEDF significantly reduced myocardial infarct size and enhanced cardiac function in rats with AMI. These data suggest that PEDF could protect cardiac function from ischemic injury, at least by means of reducing vascular permeability, cardiomyocyte apoptosis and myocardial infarct size.

The present study investigated the recovery and intrathecal administration of human umbilical cord‑derived mesenchymal stem cells (HUC‑MSCs) by lumbar puncture and analyzed the technical difficulties and short and long‑term effects of UC‑MSC transplantation in various neurological conditions. In total, 100 patients who underwent subarachnoid placement of UC‑MSCs between December 2006 and May 2010 were included in the present study. The present study evaluated the number of attempts, localization of subarachnoid space and postprocedural complications. The Hauser Ambulation Index was employed for functional assessment. Clinical symptoms, the associated biochemical index and photographic examinations were observed regularly. HUC‑MSCs were transplanted into mice as well as patients in order to determine the underlying therapeutic mechanisms. Technical difficulties were encountered in 31 patients (31%) in the form of general anesthesia supplementation and difficulty localizing lumbar space. Side effects were observed in 22 (22%) patients, which resolved with symptomatic treatment within 48 h. On follow‑up one year later, functional indices improved in 47 (47%) patients. Transplantation of HUC‑MSCs inhibited apoptosis and the protein expression of c-Jun N-terminal kinase and p38 as well as triggered the phosphorylation of P‑42/44 extracellular-signal-regulated kinase. In conclusion, intrathecal administration of UC‑MSCs is safe and effective with no long‑term adverse effects in neurological disorders. HUC‑MSCs may achieve these effects via the mitogen‑activated protein kinase pathway. The results suggest that there is a promise of restoration of lost tissue and improvement of function in patients with profound neurological defects. These data support expanded double blind, placebo‑controlled studies for this treatment modality.

Arsenic trioxide has been successfully used for the treatment of patients with acute promyelocytic leukemia (APL) worldwide. Recently, it has also been further developed to treat solid tumors in clinical trials. However, the therapeutic effects on malignant tumors appeared to be unsatisfactory, as these cells exhibited resistance towards arsenic. In this study, we explored new therapeutic strategies for treatment of human breast cancer MCF-7 cells based on arsenic metabolites. The MCF-7 cells were exposed to three arsenic species, namely, inorganic arsenite (iAs(III)) and its intermediate metabolites monomethylarsonous acid (MMA(III)) and dimethylarsinous acid (DMA(III)) either alone or in combination with cryptotanshinone (CPT) to establish their anticancer effects against MCF-7 cells. Surprisingly, MCF-7 cells were shown to be resistant to both iAs(III) and CPT when used alone; however, they were shown to be relatively sensitive to treatment when exposed to MMA(III) and DMA(III) alone. Conversely, the combination of MMA(III) with CPT showed significantly enhanced anticancer effects on MCF-7 cells at low doses, but no appreciable effect was observed upon exposure to the other two arsenic species with CPT. In addition, remarkable redistribution of pro-apoptosis related proteins Bax and Bak was observed in the mitochondria, together with activation of poly(ADP-ribose) polymerase (PARP) and caspase-9 after exposure to the combination of MMA(III) with CPT. Furthermore, we clearly found that induction of apoptosis in MCF-7 cells was predominantly triggered by endoplasmic reticulum (ER) stress after exposure to the combination of MMA(III) with CPT.

Although tumor cell lysate (TCL) is a type of immunocyte stimulator, its immunosuppressive function must not be ignored. The present study reported that TCL prepared from a Lewis lung cancer cell was able to induce the development of immunosuppressive macrophages (MΦ) and tolerogenic dendritic cells. In addition, TCL upregulated the expression of CD69 in mouse splenocytes, and cell apoptosis and the percentage of regulatory T cells in mouse splenocytes simultaneously increased. Furthermore, the present study found that the immunosuppressive factor, hyaluronan, and the apoptosis inducers, Fas ligand and transforming growth factor-β, are present in TCL. These components may be associated with the emergence of immunosuppressive cells or splenocyte apoptosis. Thus, the present study has enriched our understanding of the composition of TCL and its negative regulatory effect on immunocytes.

Pseudolaric acid B (PAB) is a diterpene acid, isolated from the root and trunk bark of Pseudolarix kaempferi Gordon (Pinaceae). Previous studies demonstrated that PAB induced G2/M arrest and apoptosis in several cancer cell lines, but the relationship between G2/M arrest and apoptosis is still unclear. We examined the relevant signaling pathways for human cervical carcinoma HeLa cells treated with 1 μM PAB. Intriguingly, we found that activation of ATM-p53 signaling pathway by the treatment with 1 μM PAB played a protective role for the subsequent apoptosis. Although the treatment with 1 μM PAB up-regulated the expression of cyclin B1 and p-Histone 3 (mitotic markers) at 12 h, the expression decreased at 24 and 36 h along with the up-down expression of mitotic markers. The expressions of p-ATM and p-p53 that were involved in G2/M arrest increased at 12h after treatment with PAB. However, a prolonged treatment with PAB (longer than 24 h) caused cell apoptosis. When the cells were arrested in G1 or S phase by the treatment with serum starvation, cytosine β-D-arabinofuranoside (Ara-C) or hydroxyurea (Hu), the apoptotic ratio induced by PAB decreased., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Studies have shown that ruthenium complexes have relatively strong anticancer activity, cell uptake of drugs have a crucial impact on the pharmacological activity, using autofluorescence of ruthenium complexes could effectively track cancer cells and drug distribution, transport accurately in real time. In this work, we present the synthesis and detailed characterization of two novel Ru(II) complexes with hydrophobic ancillary ligands, namely [Ru(bpy)2(5-idip)](2+) (RBD) and [Ru(phen)2(5-idip)](2+) (RPD) (5-idip = 2-indole-[4,5-f][1,10]phenanthroline). We have shown that RPD can enter the HeLa cells efficiently through non-endocytotic, but energy-dependent mechanism and first accumulated in lysosomes, and then escape from the lysosomes and localize within the nuclei, efficiently lead to the inhibition of DNA transcription and translation and induced cell apoptosis. Further studies on the mechanism of apoptosis in HeLa cells demonstrate that RPD is able to induce mitochondria-mediated apoptosis in HeLa cells through activation of initiator caspase-9 and down-stream effector caspase-3 and -7 and cleavage of PARP. We have also demonstrated that RPD bind to telomeric G-quadruplex DNA effectively and selectively, together with increased p21 and p16 expression. Our findings suggest that RPD induces HeLa cell apoptosis through mitochondria-mediated pathway and inhibition of telomerase activity. RPD may be a candidate for further evaluation as a chemotherapeutic agent for human cancers., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Tumor necrosis factor-α (TNF-α) is a critical proinflammatory cytokine regulating neuroinflammation. Elevated levels of TNF-α have been associated with various neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. However, the signaling events that lead to TNF-α-initiated neurotoxicity are still unclear. Here, we report that RIP3-mediated necroptosis, a form of regulated necrosis, is activated in the mouse hippocampus after intracerebroventricular injection of TNF-α. RIP3 deficiency attenuates TNF-α-initiated loss of hippocampal neurons. Furthermore, we characterized the molecular mechanism of TNF-α-induced neurotoxicity in HT-22 hippocampal neuronal cells. HT-22 cells are sensitive to TNF-α only upon caspase blockage and subsequently undergo necrosis. The cell death is suppressed by knockdown of CYLD or RIP1 or RIP3 or MLKL, suggesting that this necrosis is necroptosis and mediated by CYLD-RIP1-RIP3-MLKL signaling pathway. TNF-α-induced necroptosis of HT-22 cells is largely independent of both ROS accumulation and calcium influx although these events have been shown to be critical for necroptosis in certain cell lines. Taken together, these data not only provide the first in vivo evidence for a role of RIP3 in TNF-α-induced toxicity of hippocampal neurons, but also demonstrate that TNF-α promotes CYLD-RIP1-RIP3-MLKL-mediated necroptosis of hippocampal neurons largely bypassing ROS accumulation and calcium influx.

Doxorubicin (DOX) is a potent available antitumor drug; however, its clinical use is limited by the cardiotoxicity. Salidroside (SLD), with strong antioxidative and cytoprotective actions, is of particular interest in the development of antioxidative therapies for oxidative injury in cardiac diseases. Now, the protection and underlying mechanisms of SLD against DOX-induced cardiotoxicity are still unknown. In the present study, we revealed both antioxidative mechanism and Bcl2-dependent survival signaling involved in SLD's protection. We observed that DOX exposure induced mortality elevation, body weight loss, and cardiac dysfunction in mice, increased lactate dehydrogenase leakage and cardiomyocyte apoptosis, but decreased cell viability and size in cardiac tissues and cultured H9c2 cells, respectively, which were effectively antagonized by SLD supplement. We further observed that SLD significantly reduced the intercellular oxidative stress level, partly by inhibiting NOX1 expression and augmenting the expression and activities of the endogenous antioxidative enzymes, catalase, and manganese superoxide dismutase. In addition, SLD treatment upregulated the antiapoptotic Bcl2 and downregulated the proapoptotic Bax and inhibited a downstream pathway of Bcl2/Bax and caspase-3 activity. Our results indicated that SLD effectively protected the cardiomyocytes against DOX-induced cardiotoxicity by suppressing the excessive oxidative stress and activating a Bcl2-mediated survival signaling pathway.

Cis-diamminedichloroplatinum (II) (cisplatin) is one of the most active antitumor agents used in human chemotherapy of non-small cell lung cancer. Cisplatin forms crosslinked DNA adducts and its cytotoxicity has been shown to be mediated by propagation of DNA damage recognition signals to downstream pathways prompting apoptosis. The steps involved in the process include changes in Ca(2+) signaling with dysregulated tumor cell turn-over. Stromal interaction molecules 1 (STIM1), as one of the most potent tumor suppressor genes, are identified as the endoplasmic-reticulum (ER) Ca(2+) sensor controlling store-operated Ca(2+) entry (SOCE) in non-excitable cells, which is main pathway to extracellular Ca(2+) influx. Its role in STIM1 cisplatin-induced apoptosis of non-small cell lung cancer was the focus of study with focus on SOCE inhibitors 2-APB- and SKF96365-cisplatin-induced apoptosis in the non-small cell lung cancer (NSCLC) cell lines A549 and H460. In this experimental model, cisplatin-induced apoptosis and decreased concentration of intracellular Ca(2+) was demonstrated. The expression of STIM1 was significantly higher in carcinoma tissue than in the adjacent non-neoplastic lung tissue. These findings support the conclusion that STIM1 may play an important role in the development of NSCLC which makes drugs that repress the expression of STIM1 to be a potential target for lung cancer therapy., (Copyright © 2013 Elsevier GmbH. All rights reserved.)

Objective: To investigate the role of calcium dyshomeostasis in 1-methyl-4-phenylpyridinium ion (MPP⁺)-induced apoptosis of human neuroblastoma SH-SY5Y cells., Methods: The viability of SH-SY5Y cells exposed to varying concentrations of MPP⁺ was assessed using MTT colorimetric assay, and MPP⁺-induced cell apoptosis was detected with hoechst 33342 staining and Annexin V+PI assay. Western blotting and rhodamine 123 staining were employed to examine the changes in cellular poly(ADP-ribose) polymerase (PARP) protein expression and mitochondrial membrane potential in response to MPP⁺ exposure. The effects of ruthenium red and/or MPP⁺ on calcium concentration in the cytoplasm, mitochondria and endoplasmic reticulum were evaluated using confocal microscopy., Results: MPP⁺ induced apoptosis and caused reduced cell viability and mitochondrial membrane potential in SH-SY5Y cells. The cells exposed to MPP⁺ showed a lowered calcium concentration in the cytoplasm and endoplasmic reticulum and an increased mitochondrial Ca²⁺ uptake. Ruthenium red rescued MPP⁺-induced apoptosis and mitochondrial membrane potential reduction, reduced PARP cleavage, and inhibited the increase of mitochondrial matrix free Ca²⁺ in the cells exposed to MPP⁺., Conclusion: Mitochondrial calcium overload plays an important role in MPP⁺-induced apoptosis of SH-SY5Y cells, which is closely associated with dysregulation of intracellular Ca²⁺ homeostasis.

Ghrelin is a multifunctional peptide that actively protects against cardiovascular ischemic diseases, but the underlying mechanisms are unclear. We used CoCl(2) to mimic hypoxic conditions in cardiac H9c2 cells in order to study the mechanism by which ghrelin protects cardiac myocytes against hypoxic injury by regulating the content of intracellular ROS and autophagy levels. Cell apoptosis and necrosis were evaluated by the flow cytometry assay, Hoechst staining, and LDH activity. Cell viability was detected by the WST-1 assay; ROS levels were assessed using DCFH2-DA; and Nox1, catalase and Mn-SOD were assayed by real-time PCR and activity assays. LC3II was measured by Western blot analysis. We observed that CoCl(2) induced apoptosis and death of H9c2 cells in a dose- and time-dependent manner. This was characterized by an increase in cell apoptosis, LDH activity, ROS content, Nox1 expression, and autophagy levels and a decrease in cell viability, catalase, and Mn-SOD activities. Ghrelin treatment significantly attenuated CoCl(2)-induced hypoxic injury by decreasing cell apoptosis, LDH activity, ROS content, and Nox1 expression and increasing cell viability, autophagy levels, catalase, and Mn-SOD mRNA levels and activities. Further experiments revealed that inhibiting autophagy using 3-MA or AMPK pathway with compound C almost abrogated the induction of ghrelin in autophagy. This was associated with a decrease in cell viability and an increase in LDH activity. Our results indicate that ghrelin protected cardiac myocytes against CoCl(2)-induced hypoxic injury by decreasing Nox1 expression, increasing the expression and activity of endogenous antioxidant enzymes, and inducing protective autophagy in an AMPK-dependent manner., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Aim: Vestibular hair cell loss in response to different stimuli may be attributable to the occurrence of apoptosis, in which apoptosis-inducing factor (AIF) is an important regulator mediating apoptotic process independent of caspases. This study was designed to investigate the possible involvement of AIF in gentamicin (GM)-induced vestibular hair cell death., Methods: Vestibular organs from postnatal day 3 or 4 rats were maintained in tissue culture and were exposed to 2 mg/ml GM for up to 72 h. Vestibular hair cell viability was quantified by MTT assay. Apoptosis was determined by flow cytometry. AIF activation was examined by RT-PCR. The expressions of the mitochondrial protein and cytoplasm protein of AIF were detected by Western blot., Results: GM could significantly inhibit the cell viability of vestibular hair cells in a dose- and time-dependent manner. The number of apoptotic cells treated with GM was higher than that of cells not treated with GM. RT-PCR showed upregulation of AIF mRNA under GM. Western blot showed that AIF from mitochondria was decreased, whereas AIF from cytoplasm was increased after GM exposure., Conclusions: AIF participates in GM-induced apoptosis of vestibular hair cells., (Copyright © 2011 S. Karger AG, Basel.)

Background: Hypoxia/reoxygenation(H/R)-induced apoptosis of cardiomyocytes plays an important role in myocardial injury. Lycopene is a potent antioxidant carotenoid that has been shown to have protective properties on cardiovascular system. The aim of the present study is to investigate the potential for lycopene to protect the cardiomyocytes exposed to H/R. Moreover, the effect on mitochondrial function upon lycopene exposure was assessed., Methods and Findings: Primary cardiomyocytes were isolated from neonatal mouse and established an in vitro model of H/R which resembles ischemia/reperfusion in vivo. The pretreatment of cardiomyocytes with 5 µM lycopene significantly reduced the extent of apoptosis detected by TUNEL assays. To further study the mechanism underlying the benefits of lycopene, interactions between lycopene and the process of mitochondria-mediated apoptosis were examined. Lycopene pretreatment of cardiomyocytes suppressed the activation of the mitochondrial permeability transition pore (mPTP) by reducing the intracellular reactive oxygen species (ROS) levels and inhibiting the increase of malondialdehyde (MDA) levels caused by H/R. Moreover, the loss of mitochondrial membrane potential, a decline in cellular ATP levels, a reduction in the amount of cytochrome c translocated to the cytoplasm and caspase-3 activation were observed in lycopene-treated cultures., Conclusion: The present results suggested that lycopene possesses great pharmacological potential in protecting against H/R-induced apoptosis. Importantly, the protective effects of lycopene may be attributed to its roles in improving mitochondrial function in H/R-treated cardiomyocytes.

Hepatocellular carcinoma (HCC) is inherently resistant to the majority of clinical anticancer drugs. To obtain drugs that can circumvent or evade such inherent drug resistance of HCC, we investigated the effect of the marinely derived steroid methyl spongoate (MESP) on HCC cells. MESP displayed potent cell killing against a panel of six HCC cell lines, independent of their expression of drug transporters. MESP did not change the function of the drug transporters, and its cell killing was not impaired in multidrug-resistant cancer cells overexpressing the transporters. The cell killing of MESP was irrelevant to estrogen or androgen signaling and was not associated with cell cycle progression, inhibition of microtubules, and topoisomerases. In contrast, MESP potently induced apoptosis via activation of a proapoptotic caspase cascade and relief of the suppression of antiapoptotic signal transducers and activators of transcription 3 (STAT3) signaling. MESP inhibited the phosphorylation of STAT3, a critical survival signaling factor that reduced the expression of the antiapoptotic protein x-linked inhibitor of apoptosis protein but enhanced the expression of the proapoptotic protein Bax, thus promoting caspase-dependent apoptosis. These data reveal that MESP may well serve as an important candidate drug lead for HCC therapy.

Vitamin K(2) (VK(2)) can exert cell growth inhibitory effects in various human cancer cells. In this study, we investigated the cell growth inhibitory effects of VK(2) in hepatocellular carcinoma Smmc-7721 cells and the mechanisms involved. We found that VK(2)-inhibited cell proliferation in Smmc-7721 cells in a dose-dependent manner, and the IC50 of VK(2) in Smmc-7721 cells was 9.73 microM at 24 h. The data from flow cytometric analyses, DNA fragmentation assays, and caspase 3 activity assays revealed that apoptosis was the determining factor in VK(2) activity. Furthermore, a significant increase in p53 phosphorylation and protein level was exhibited in apoptotic cells treated with VK(2), although there were no changes in p53 mRNA expression. Bax expression was unaffected by VK(2) in Smmc-7721 cells. In addition, our study showed that caspase 3 was activated by caspase 8, not caspase 9, in Smmc-7721 cells treated with VK(2). In summary, these data suggested that VK(2) can inhibit the growth of Smmc-7721 cells by induction of apoptosis involving caspase 8 activation and p53. This apoptotic process was not mediated by the intrinsic apoptotic pathway.

Objective: To investigate the mechanism related to the inhibition of leukemia K562 cells by berbamine., Methods: After K562 cells were treated with 8 microg/ml berbamine, the expression levels of NF-kappaB, IkappaBalpha, pIkappaBalpha, IKKalpha, A20 were determined by Western blot., Results: With the exposure time extending, the total NF-kappaB showed no significant changes,but NF-kappaB expression in nucleus was decreased dramatically after treated with berbamine for 24 h. The ratio of nucleus NF-kappaB/histone H1 was decreased from 59.2%,gradually to 31.4%,19.7%,4.1%,and 0%. At the same time,the expression of A20 was increased,while the expression of pIkappaBalpha, IKKalpha was down-regulated., Conclusion: Berbamine may induce K562 cell apoptosis through NF-kappaB pathway. Down-regulation of NF-kappaB and bcr-abl gene expression might be involved in cell apoptosis.

Aim of the study: Cardiovascular disease (CVD) seriously endangers human health and is characterized by high mortality and disability. The effectiveness of Dracocephalum moldavica L. in the treatment of CVD has been proven by clinical practice. However, the mechanism by which DML can treat CVD has not been systematically determined. Materials and methods: The active compounds in DML were screened by literature mining and pharmacokinetic analysis. Cytoscape software was used to construct the target-disease interaction network of DML in the treatment of CVD. Gene ontology and signalling pathway enrichment analyses were performed. The key target pathway network of DML compounds was constructed and verified by pharmacological experiments in vitro. A hydrogen glucose deprivation/reoxygenation model was established in H9c2 cells using hypoxia and glucose deprivation for 9 h combined with reoxygenation for 2 h. The model simulated myocardial ischaemic reperfusion injury to investigate the effects of total flavonoids of Cymbidium on cell viability, myocardial injury markers, oxidative stress levels, and reactive oxygen radical levels. Western blot analysis was used to examine NOX-4, Bcl-2/Bax, and PGC-1α protein expression. Results: Twenty-seven active components were screened, and 59 potential drug targets for the treatment of CVD were obtained. Through the compound-target interaction network and the target-disease interaction network, the key targets and key signalling pathways, such as NOX-4, Bcl-2/Bax and PGC-1α, were obtained. TFDM significantly decreased LDH and MDA levels and the production of ROS and increased SOD activity levels in the context of OGD/R injury. Further studies indicated that NOX-4 and Bax protein levels and the p-P38 MAPK/P38 MAPK andp-Erk1/2/Erk1/2 ratios were suppressed by TFDM. The protein expression of Bcl-2 and PGC-1α was increased by TFDM. Conclusions: Our results showed that DML had multicomponent, multitarget and multichannel characteristics in the treatment of CVD. The mechanism may be associated with the following signalling pathways: 1) the NOX-4/ROS/p38 MAPK signalling pathway, which inhibits inflammation and reactive oxygen species (ROS) production, and 2) the Bcl-2/Bax and AMPK/SIRT1/PGC-1α signalling pathways, which inhibit apoptosis. [ABSTRACT FROM AUTHOR]

Background: Drug resistance is a prominent problem in the treatment of tuberculosis, so it is urgent to develop new anti- tuberculosis drugs. Here, we investigated the effects and mechanisms of cisplatin (DDP) on intracellular Mycobacterium smegmatis to tap the therapeutic potential of DDP in mycobacterial infection. Results: Macrophages infected with Mycobacterium smegmatis were treated with DDP alone or combined with isoniazid or rifampicin. The results showed that the bacterial count in macrophages decreased significantly after DDP (≤ 6 μg/mL) treatment. When isoniazid or rifampicin was combined with DDP, the number of intracellular mycobacteria was also significantly lower than that of isoniazid or rifampicin alone. Apoptosis of infected cells increased after 24 h of DDP treatment, as shown by flow cytometry and transmission electron microscopy detection. Transcriptome sequencing showed that there were 1161 upregulated and 645 downregulated differentially expressed genes (DEGs) between the control group and DDP treatment group. A Trp53-centered protein interaction network was found based on the top 100 significant DEGs through STRING and Cytoscape software. The expression of phosphorylated p53, Bax, JAK, p38 MAPK and PI3K increased after DDP treatment, as shown by Western blot analysis. Inhibitors of JAK, PI3K or p38 MAPK inhibited the increase in cell apoptosis and the reduction in the intracellular bacterial count induced by DDP. The p53 promoter Kevetrin hydrochloride scavenges intracellular mycobacteria. If combined with DDP, Kevetrin hydrochloride could increase the effect of DDP on the elimination of intracellular mycobacteria. In conclusion, DDP at low concentrations could activate the JAK, p38 MAPK and PI3K pathways in infected macrophages, promote the phosphorylation of p53 protein, and increase the ratio of Bax to Bcl-2, leading to cell apoptosis, thus eliminating intracellular bacteria and reducing the spread of mycobacteria. Conclusion: DDP may be a new host-directed therapy for tuberculosis treatment, as well as the p53 promoter Kevetrin hydrochloride. [ABSTRACT FROM AUTHOR]

Background: L‐arginine (L‐arg) can reduce apoptosis in a variety of cells. Cementoblast apoptosis is related to root resorption during orthodontic treatment. In the present study, we aimed to study the regulatory effect and potential mechanism of L‐arg on cementoblast apoptosis and root resorption. Methods: The apoptosis‐related mRNA and protein expression of murine cementoblast (OCCM‐30) was assessed after L‐arg treatment. To investigate the role of Sirtuin 1 (Sirt1) and autophagy in L‐arg resistance to cementoblast apoptosis and root absorption, resveratrol, and EX527 were used to activate or inhibit Sirt1, and chloroquine (CQ) was used to inhibit autophagy. Results: In vitro, L‐arg inhibited hypoxia‐induced apoptosis in OCCM‐30. Further, L‐arg increased Sirt1 expression whereas Sirt1 suppression by EX527 reversed the inhibitory effect of L‐arg on cell apoptosis. Sirt1 activator resveratrol increased the ratio of microtubule‑associated protein light chain 3 (LC3) II/I and decreased the expression of SQSTM1/p62 (p62), suggesting autophagy activation. Autophagy enhancement could reduce apoptosis. Caspase‐3 and Bax expression was decreased, and Bcl‐2 expression was increased. When autophagy was inhibited by CQ, the positive effects of Sirt1 were attenuated. In vivo, L‐arg application reduced root resorption in rats, as demonstrated by decreased root absorption volume. Similarly, L‐arg upregulated Sirt1, which activated autophagy in the root resorption model, and less root resorption was observed in the Sirt1 activation group. Conclusion: L‐arg reduced cementoblast apoptosis in hypoxia and reduced root resorption induced by loading force in rats, which may be partly mediated by Sirt1‐enhanced autophagy. [ABSTRACT FROM AUTHOR]

The restoration of the Wnt/β-catenin pathway to alleviate alcoholic fatty liver disease (AFLD) progression is under study as a new strategy for alcoholic liver disease (ALD) treatment. Recent studies have indicated that interferon-stimulated gene 15 (ISG15) can covalently bind to β-catenin by HECT E3 ubiquitin ligase 5 (HERC5), leading to ISG degradation and downregulation of β-catenin levels. However, the relationship between β-catenin and the ISG15 system in AFLD remains unclear. Here, we explored the roles of the ISG15 system in β-catenin activation and in the pathogenesis of alcohol-induced liver injury and steatosis. In this study, HERC5 silencing upregulated β-catenin protein expression and inhibited lipid metabolism disorders and cell apoptosis. Reduced β-catenin protein expression, increased lipid metabolism disorders, and cell apoptosis were detected in cells induced with HERC5 overexpression, which was reversible with the reactive oxygen species (ROS) inhibitor. All the above results were statistically analyzed. Thus, these observations demonstrate that β-catenin ISGylation is a prominent regulator of ALD pathology, which works by regulating ROS to induce lipid metabolism disorders and cell apoptosis. Our findings provided the mechanism involved in the β-catenin ISGylation, allowing for future studies on the prevention or amelioration of liver injury in ALD. [ABSTRACT FROM AUTHOR]