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To explore the active substances exerting anti-tumour effect in lemon essential oil and the molecular mechanism inhibiting the proliferation of head and neck cancer cells SCC15 and CAL33, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay(MTT) was utilized to identify the active component inhibiting the proliferation of head and neck cancer cells, namely citral. The IC_(50) of citral inhibiting the proliferation of head and neck cancer cells and normal cells were also determined. In addition, a 5-ethynyl-2'-deoxyuridine(EdU) staining assay was used to detect the effect of citral on the proliferation rate of head and neck cancer cells, and a colony formation assay was used to detect the effect of citral on tumor sphere formation of head and neck cancer cells in vitro. The cell cycle arrest and apoptosis induction of head and neck cancer cells by citral were evaluated by flow cytometry, and Western blot was used to detect the effect of citral on the expression levels of cell cycle-and apoptosis-related proteins in head and neck cancer cells. The findings indicated that citral could effectively inhibit the proliferation and growth of head and neck cancer cells, with anti-tumor activity, and its half inhibitory concentrations for CAL33 and SCC15 were 54.78 and 25.23 μg·mL~(-1), respectively. Furthermore, citral arrested cell cycle at G_2/M phase by down-regulating cell cycle-related proteins such as S-phase kinase associated protein 2(SKP2), C-MYC, cyclin dependent kinase 1(CDK1), and cyclin B. Moreover, citral increased the cysteinyl aspartate-specific proteinase-3(caspase-3), cysteinyl aspartate-specific proteinase-9(caspase-9), and cleaved poly ADP-ribose polymerase(PARP). It up-regulated the level of autophagy-related proteins including microtubule associated protein 1 light chain 3B(LC3B), sequestosome 1(P62/SQSTM1), autophagy effector protein Beclin1(Beclin1), and lysosome-associate membrane protein 1(LAMP1), suggesting that citral could effectively trigger cell apoptosis and cell autophagy in head and neck cancer cells. Furthermore, the dual-tagged plasmid system mCherry-GFP-LC3 was used, and it was found that citral impeded the fusion of autophagosomes and lysosomes, leading to autophagic flux blockage. Collectively, our findings reveal that the main active anti-proliferation component of lemon essential oil is citral, and this component has a significant inhibitory effect on head and neck cancer cells. Its underlying molecular mechanism is that citral induces apoptosis and autophagy by cell cycle arrest and ultimately inhibits cell proliferation.

Spinal cord injury (SCI) leads to severe and long-lasting neurological disability. Presently, the lack of effective therapies for SCI is largely attributable to an incomplete understanding of its pathogenesis. F-box and WD repeat domain-containing protein 7 (FBW7, also known as FBXW7) is a type of E3 ubiquitin ligase complex, and plays essential roles in regulating different pathological and physiological processes. In this study, we attempted to explore the effects of FBW7 on SCI progression by the in vivo and in vitro experiments. SCI mice showed significantly reduced expression of FBW7 in spinal cord tissues. Promoting FBW7 expression via intrathecal injection of AAV9/FBW7 effectively improved locomotor function in SCI mice. Neuronal death in spinal cords of SCI mice was obviously ameliorated by FBW7 over-expression, along with greatly decreased expression of cleaved Caspase-3. In addition, microglial activation in spinal cord specimens was detected in SCI mice through increasing Iba-1 expression levels, which was, however, attenuated in SCI mice injected with AAV9/FBW7. Additionally, FBW7 over-expression dramatically restrained inflammatory response in spinal cord tissues of SCI mice, as evidenced by the down-regulated expression of tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β) through blocking the activation of nuclear factor-κB (NF-κB) signaling. These anti-inflammatory effects of FBW7 were confirmed in LPS-stimulated mouse microglial BV2 cells. Finally, our in vitro studies showed that conditional medium (CM) collected from LPS-incubated BV2 cells markedly induced apoptosis in the isolated primary spinal neurons; However, this effect was overtly ameliorated by CM from LPS-exposed BV2 cells over-expressing FBW7. Thus, FBW7-regulated inflammation in microglial cells was involved in the amelioration of neuronal apoptosis during SCI development. Collectively, these findings illustrated that FBW7 expression was down-regulated in spinal cords of SCI mice, and promoting its expression could effectively mitigate SCI progression by repressing microglial inflammation and neuronal death., (Copyright © 2020. Published by Elsevier Inc.)

Acetaminophen (APAP) is commonly used to relieve pain and fever in a clinical setting, but its excessive use can lead to serious hepatotoxicity. Our previous study demonstrated that polydatin (PD) can effectively attenuate d-galactose- and alcohol-induced hepatotoxicity, however, its effect on APAP-induced hepatotoxicity is still unknown. In this study, we explore the protective effect and potential mechanism of PD against APAP-induced hepatotoxicity in mice. The results indicate that PD effectively improves the survival of mice with APAP-induced hepatotoxicity, significantly alleviating histopathologic alterations in the liver, and decreasing the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). PD significantly and dose-dependently reduces oxidative stress by lowering the content of oxidized glutathione (GSSG), reactive oxygen species (ROS), nitric oxide (NO) and malonaldehyde (MDA), while enhancing the hepatic activities of glutathione (GSH), glutathione peroxidase (GSH-Px) and the GSH/GSSG ratio. Meanwhile, PD also substantially inhibits the levels and mRNA expressions of inducible nitric oxide synthase (iNOS) and NADPH oxidase 2 (NOX2). Additionally, PD markedly arrests apoptosis by assuaging TUNEL-positive hepatocytes and the apoptotic index, decreasing the levels and expression of cytochrome c (CytC), cleaved-caspase-9, apoptotic protease activating factor 1 (Apaf-1), cleaved-caspase-3, and Bax and increasing the level and expression of Bcl-2. Overall, PD pretreatment shows a potent protective effect against APAP-induced hepatotoxicity by relieving oxidative stress and inhibiting apoptosis.

Solasodine, a steroidal alkaloid isolated from solanaceous species, exhibits anticancer activities on several cell lines. This study aimed to explore the antitumor potential of solasodine on ovarian cancer cells. The MTT assay, lactate dehydrogenase release assay, Hoechst 33342 staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine staining assay, and Annexin V/PI assay were conducted to investigate the antiproliferation and apoptosis-inducing effects of solasodine. Monodansylcadaverine staining was performed to label the acidic puncta on ovarian cancer HEY cells. A wound healing assay and Transwell assay were carried out to determine whether solasodine elicits an antimetastatic effect on HEY cells. A gelatin zymography assay was applied to detect the enzymatic activities of matrix metalloproteinases. Western blot was employed to examine relevant protein expression. Results revealed that solasodine inhibited cell viabilities in a time- and dose-dependent manner, triggered apoptotic body formation, reduced cell mitochondrial membrane potential, and interfered with autolysosome degradation in ovarian cancer cells. Solasodine also suppressed the migration and invasion of HEY cells by downregulating matrix metalloproteinase expression and activities. This study could be used as a basis for further studies on the molecular mechanisms of the antiproliferation, apoptosis-inducing, autophagy-modifying, and antimetastatic activities of solasodine., (Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: To investigate the occurrence of apoptosis and autophagy on human gastric cancer cells after treatment by Tanshinone I, as well as the relationship between them., Methods: BGC823 and SGC7901 cells were treated with Tanshinone I; the cell proliferation was measured using CCK-8 and clone formation assay; and the expression of apoptosis- and autophagy-associated proteins was detected by Western blot. Autophagic vacuoles in cells were observed with LC3 dyeing using confocal fluorescent microscopy, and apoptotic cells were detected via flow cytometry. Bcl-2 was overexpressed in gastric cells treated with Tanshinone I or not, and autophagy relative protein was investigated; the interaction between Beclin-1 and Bcl-2 was detected by immunoprecipitation. Cell apoptosis was detected when autophagy was inhibited by ATG7-siRNA. Tumor growth was assessed by subcutaneous inoculation of cells into BALB/c nude mice., Results: Tanshinone I inhibited the proliferation of BGC823 and SGC7901 cells, and induced cell apoptosis by inhibiting anti-apoptosis protein Bcl-2. Tanshinone I also increased the conversion of LC3I to LC3II and triggered autophagosome formation, without changing the expression of Beclin-1. However, the Beclin-1 VPS34 complexes were increased after Tanshinone I treatment via inhibiting Bcl-2 expression. Moreover, disturbing autophagy by knockdown of ATG7 expression contributed to Tanshinone I-induced apoptosis. In vivo assay showed that combination with autophagy inhibitor chloroquine in nude mice bearing BGC823 xenograft significantly augmented the antitumor effect of Tanshinone I., Conclusions: Tanshinone I induced apoptosis and pro-survival autophagy via inhibiting Bcl-2 expression on gastric cancer, and the combination of chloroquine and Tanshinone I could inhibit tumor growth more efficiently than monotherapy, which might be considered as an effective strategy for the treatment for gastric cancer.

Objective: To investigate the effect of magnolol on proliferation and apoptosis of HL-60 cells and its mechanism., Methods: MTT assay was used to measure the proliferation of HL-60 cells after treatment with different concentration of magnolol (5, 10, 20, 40, 80 and 160 µg/ml). The morphological changes of HL-60 cells were examined by light microscopy, and DAPI staining was performed to observe the nuclear morphology of HL-60 cells. The early cell apoptosis was detected by flow cytometry with Annexin V-FITC/PI double-staining. RT-PCR was carried out to examine the mRNA expression of BAX and BCL-2. Western blot was performed to detect the protein expression of caspase family., Results: The magnolol inhibited HL-60 cell proliferation, and the inhibitory rate of cell proliferation increased significantly in a dose- and time- dependent manner (P < 0.05). HL-60 cells became small, even apoptotic bodies appeared after treatment with magnolol. In addition, nuclear condensation or fragmentation could be observed, which is the typical morphological features of apoptosis. When HL-60 cells were treated with 40 µg/ml of magnolol for 24 h, the ratio of early apoptotic cells reached to (11.7 ± 2.4) %, which was significant different from control (1.4 ± 1.1) % (P < 0.05). RT-PCR results showed that treatment of HL-60 cells with magnolol up-regulated the expression of BAX, whereas down-regulated the expression of BCL-2. Western blot results showed that the cleavages of caspase-3, -8 and -9 were significantly enhanced by magnolol., Conclusion: The magnolol can significantly inhibit the proliferation of HL-60 cells and induce the apoptosis of HL-60 cells, which may occur through up-regulation of BAX, down-regulation of BCL-2 and the activation of caspases.

Lycopene (Ly), the most common type of antioxidant in the majority of diet types, provides tolerance to ischemia/reperfusion injury. However, the underlying mechanism of the protective effects observed following Ly administration remains poorly investigated. The aim of the current study was to investigate whether Ly prevents damage to hypoxia/reoxygenation (HR)‑induced H9C2 myocardioblasts in an autophagy‑dependent manner. The levels of autophagic markers were detected using western blotting, the level of apoptosis was detected using western blotting and flow cytometry. The activation of autophagy was impaired via knockdown of the expression of 'microtubule‑associated protein 1‑light chain 3β (MAP1LC3B)' and 'Beclin 1'. After 16 h hypoxia, followed by 2 h reoxygenation, the expression levels of the microtubule‑associated protein 1A/1B‑light chain 3 (LC3) and Βeclin 1 autophagic biomarkers, and cell viability were reduced, whereas the percentage of apoptotic cells, and the expression levels of the Bax/B‑cell lymphoma 2 (Bcl‑2) and active caspase‑3 apoptotic biomarkers were increased. Pre‑incubation of the cells with different Ly concentrations reversed the HR‑induced inhibition of autophagy and cell viability, and the HR‑induced elevation in apoptotic levels. The induction of autophagy was accompanied by reduced apoptosis, and decreased expression levels of Bax/Bcl‑2 and active caspase‑3. In addition, the impairment of autophagy by silencing the expression of MAP1LC3B and Beclin 1 accelerated HR‑induced H9C2 cell apoptosis and the Ly‑mediated protective effects disappeared. Furthermore, Bax/Bcl‑2 and active caspase‑3 expression levels were increased. Moreover, Ly‑induced autophagy was associated with increased adenosine monophosphate kinase (AMPK) phosphorylation. Suppressed AMPK phosphorylation using compound C terminates Ly‑mediated cytoprotective effects. Ly treatment improves cell viability and reduces apoptosis as a result of the activation of the adaptive autophagic response on HR‑induced H9C2 myocardioblasts. AMPK phosphorylation may be involved in the progression.

Paeoniflorin (PF) is one of the main effective components extracted from the root of Paeonia lactiflora, which has been used clinically to treat hepatitis in traditional Chinese medicine, but the details of the underlying mechanism remain unknown. The present study was designed to investigate the mechanism of protective effect of PF on d-galactosamine (GalN) and tumor necrosis factor-α (TNF-α)-induced cell apoptosis using human L02 hepatocytes. Our results confirmed that PF could attenuate GalN/TNF-α-induced apoptotic cell death in a dose-dependent manner. The disruption of mitochondrial membrane potential and the disturbance of intracellular Ca(2+) concentration were also recovered by PF. Western blot analysis revealed that GalN/TNF-α induced the activation of a number of signature endoplasmic reticulum (ER) stress and mitochondrial markers, while PF pre-treatment had a marked dose-dependent suppression on them. Additionally, the anti-apoptotic effect of PF was further evidenced by the inhibition of caspase-3/9 activities in L02 cells. These findings suggest that PF can effectively inhibit hepatocyte apoptosis and the underlying mechanism is related to the regulating mediators in ER stress and mitochondria-dependent pathways.

Backgrounds: Autophagy is an important process in the pathogenesis of diabetes and plays a critical role in maintaining cellular homeostasis. However, the autophagic response and its mechanism in diabetic vascular endothelium remain unclear., Methods and Results: We studied high-glucose-induced renin-angiotensin system (RAS)-mitochondrial damage and its effect on endothelial cells. With regard to therapeutics, we investigated the beneficial effect of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs) against high-glucose-induced endothelial responses. High glucose activated RAS, enhanced mitochondrial damage and increased senescence, apoptosis and autophagic-responses in endothelial cells, and these effects were mimicked by using angiotensin II (Ang). The use of an ACEI or ARB, however, inhibited the negative effects of high glucose. Direct mitochondrial injury caused by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) resulted in similar negative effects of high glucose or Ang and abrogated the protective effects of an ACEI or ARB. Additionally, by impairing autophagy, high-glucose-induced senescence and apoptosis were accelerated and the ACEI- or ARB-mediated beneficial effects were abolished. Furthermore, increases in FragEL™ DNA Fragmentation (TUNEL)-positive cells, β-galactosidase activation and the expression of autophagic biomarkers were revealed in diabetic patients and rats, and the treatment with an ACEI or ARB decreased these responses., Conclusions: These data suggest that autophagy protects against senescence and apoptosis via RAS-mitochondria in high-glucose-induced endothelial cells., (© 2014 S. Karger AG, Basel.)

Furanodiene (FUR) is a natural terpenoid isolated from Rhizoma curcumae, a well-known Chinese medicinal herb that presents anti-proliferative activities in several cancer cell lines. Herein, we systematically investigated the effects of FUR on the significant processes of tumor progression with the relatively low concentrations in 95-D lung cancer cells. FUR concentration-dependently inhibited cell proliferation and blocked the cell cycle progressions in G1 phase by down-regulating the protein levels of cyclin D1 and CDK6, and up-regulating those of p21 and p27 in 95-D cells. FUR also affected the signaling molecules that regulate apoptosis in 95-D cells revealed by the down-regulation of the protein levels of full PARP, pro-caspase-7, survivin, and Bcl-2, and the up-regulation of cleaved PARP. Further studies showed that FUR enhanced the expression of light chain 3-II (LC3-II) in the protein level, indicating that autophagy is involved in this process. Besides, the adhesion ability of 95-D cells to matrigel and fibronectin was slightly inhibited after FUR treatment for 1 h in our experimental condition. FUR also slightly suppressed cell migration and invasion in 95-D cells according to the data from wound healing and Transwell assays, respectively. Taken together, FUR activated the signal molecules regulating G1 cell cycle arrest, apoptosis and autophagy, while slightly affecting the key steps of cell metastasis in 95-D lung cancer cells in the relatively low concentrations.

Isoliquiritigenin (ISL), a member of the flavonoids, has been demonstrated to possess antitumor activity in various cancer cell lines in vitro and in vivo. In this study, we investigated the antitumor effects of ISL on U87 glioma cells in vitro. As determined by MTT assay, ISL inhibited the proliferation of U87 cells in a time-dependent and dose-dependent manner. The results of fluorescence-activated cell sorting (FACS) analysis suggested that ISL induced the apoptosis of the U87 cells and blocked cell cycle progression at the S and G2/M phases. Moreover, it was identified that ISL induced the apoptosis of the U87 cells in a caspase-dependent manner. Although treatment with the pan-caspase inhibitor Z-VAD-FMK efficiently blocked the ISL-induced caspase activation, it did not eliminate the ISL-induced cell death. Further examination using western blot analysis revealed that ISL upregulated p21/WAF1 and p27. These results indicate that cell cycle arrest and the caspase-mediated apoptosis pathway may participate in the antiproliferative activity of ISL in U87 cells by regulating the expression of specific molecules.

Background: Dihydroartemisinin (DHA) exhibits potent anti-malarial and anti-cancer activities. This study aimed to investigate the anti-proliferative effects of a combination of DHA and doxorubicin (DOX) on human breast cancer cells., Methods: MTT assay and the combination index (CI) were used to show the anti-proliferative effects and calculate the synergism potential, respectively. Flow cytometry assay was used to detect apoptosis and the intracellular accumulation of DOX. JC-1 staining was used to determine the mitochondrial membrane potential. Western blot analysis was used to detect the protein expression of some apoptosis-related molecules., Results: Asynergistic anti-proliferative effect was found, and the enhanced anti-cancer activity was observed to be accompanied by the prompt onset of apoptosis in MCF-7 cells. The combinative treatment remarkably decreased the mitochondrial membrane potential and activated caspase cascades more than the mono-treatment. Pretreatment with DHA also did not influence the accumulation of DOX in MCF-7 cells., Conclusion: This study presented a new opportunity to enhance the effectiveness of future treatment regimens of breast cancer using DOX.

Cyclooxygenase-2 (COX-2) plays an important role in the carcinogenesis and progression of gastric cancer. It has been demonstrated that COX-2 overexpression depends on different cellular pathways, involving both transcriptional and post-transcriptional regulation. MicroRNAs (miRNAs) are small, noncoding RNAs that function as post-transcriptional regulators. Here, we characterize miR-101 expression and its role in the regulation of COX-2 expression, which in turn, will provide us with additional insights into the potential therapeutic benefits of exogenous miR-101 for treatment of gastric cancer. Our results showed that miR-101 levels in gastric cancer tissues were significantly lower than those in the matched normal tissue (P < 0.01). Furthermore, lower levels of miR-101 were associated with increased tumor invasion and lymph node metastasis (P < 0.05). We also found an inverse correlation between miR-101 and COX-2 expression in both gastric cancer specimens and cell lines. Significant decreases in COX-2 mRNA and COX-2 levels were observed in the pre-miR-101-infected gastric cancer cells. One possible mechanism of interaction is that miR-101 inhibited COX-2 expression by directly binding to the 3'-UTR of COX-2 mRNA. Overexpression of miR-101 in gastric cancer cell lines also inhibited cell proliferation and induced apoptosis in vitro, as well as inhibiting tumor growth in vivo. These results collectively indicate that miR-101 may function as a tumor suppressor in gastric cancer, with COX-2 as a direct target., (© 2012 The Authors Journal compilation © 2012 FEBS.)

This study was aimed to investigate the effect of baicalin on proliferation and apoptosis of HL-60 cells and its mechanism. Cell proliferation was assayed by using Cell Counting Kit-8. The morphological changes of HL-60 cells were examined by light microscopy and nucleolus morphological changes were observed by fluorescent microscopy after Hoechst 33342 staining. The early cell apoptosis was detected by using flow cytometry with Annexin V-FITC/PI double staining. The expression of caspase-3, caspase-9, Bcl-2 and Bax mRNA was detected by RT-PCR and Western blot assay was carried out to examine Bax, Bcl-2, caspase-8 and cleaved caspase-3 expression. The results showed that Baicalin inhibited the proliferation of HL-60 cells in a time- and concentration-dependent manner. HL-60 cells exhibited typical morphological features (for example, cell shrinkage, membrane blebbing and formation of apoptotic bodies). Cell apoptosis in early stage could be detected, the expression of caspase-3, caspase-9 and Bax mRNA was obviously up-regulated, while the Bcl-2 expression down-regulated, and accordingly Bcl-2/Bax ratio decreased. Such results were consistent with the expression of these proteins. In addition, the expression of cleaved caspase-8 protein was induced significantly after treated with baicalin. It is concluded that baicalin can significantly inhibit the proliferation of HL-60 cells and induce the apoptosis of HL-60 cells, which may occur through decreasing Bcl-2/Bax ratio by intrinsic pathway and through extrinsic pathway. It suggests that baicalin may be a promising drug for the therapy of acute myeloid leukemia.

Ganoderic acid DM (GADM) is a triterpenoid isolated from Ganoderma lucidum, a well-known edible medicinal mushroom. In the present study, we found that GADM effectively inhibited cell proliferation and colony formation in MCF-7 human breast cancer cells, which was much stronger than that of MDA-MB-231 breast cancer cells. GADM both concentration- and time-dependently mediated G1 cell cycle arrest and significantly decreased the protein level of CDK2, CDK6, cycle D1, p-Rb and c-Myc in MCF-7 cells. Moreover, GADM obviously induced DNA fragmentation and cleavage of PARP which are the characteristics of apoptosis and decreased the mitochondrial membrane potential in MCF-7 cells. Besides, we also showed that GADM elicited DNA damage as measured by comet assay which is a sensitive method for DNA damage detection. γ-H2AX, a marker of DNA damage, was also slightly up-regulated after treated with GADM for 6h, suggesting that the G1 cell cycle arrest and apoptosis induced by GADM may be partially resulted from GADM-induced DNA damage. These results have advanced our current understandings of the anti-cancer mechanisms of GADM., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The E2F1 transcription factor is a well known regulator of cell proliferation and apoptosis, but its role in response to DNA damage is less clear. 8-Chloro-adenosine (8-Cl-Ado), a nucleoside analog, can inhibit proliferation in a variety of human tumor cells. However, it is still elusive how the agent acts on tumors. Here we show that A549 and H1299 cells formed DNA double-strand breaks after 8-Cl-Ado exposure, accompanied by E2F1 upregulation at protein level. Overexpressed wild-type (E2F1-wt) colocalized with double-strand break marker γ-H2AX and promoted G2/M arrest in 8-Cl-Ado-exposed A549 and H1299, while expressed S31A mutant of E2F1 (E2F1-mu) significantly reduced ability to accumulate at sites of DNA damage and G2/M arrest, suggesting that E2F1 is required for activating G2/M checkpoint pathway upon DNA damage. Transfection of either E2F1-wt or E2F1-mu plasmid promoted apoptosis in 8-Cl-Ado-exposed cells, indicating that 8-Cl-Ado may induce apoptosis in E2F1-dependent and E2F1-independent ways. These findings demonstrate that E2F1 plays a crucial role in 8-Cl-Ado-induced G2/M arrest but is dispensable for 8-Cl-Ado-induced apoptosis. These data also suggest that the mechanism of 8-Cl-Ado action is complicated.

The expression and function of B7-H4, a recently identified co-inhibitory molecule of the B7 superfamily, in the pathogenesis of primary biliary cirrhosis (PBC) is still unclear. Here the expression of B7-H4 in sections from PBC patients (n = 16) was examined by immunohistochemistry and it was detected in primary bile duct epithelial cells (BECs) which were isolated from PBC patients by flow cytometry (FACs). Moreover, we also analyzed BECs-associated B7-H4 function through knock-down of its expression via RNA interference (RNAi) in vitro. Immunohistochemistry and FACs evidenced that the expression of B7-H4 was restricted in the cytoplasm of BECs from PBC patients, while it was completely absent in normal liver tissues. The cytoplasmic B7-H4 gene was cloned, and sequenced analysis showed it was encoded by the same gene to the membrane B7-H4. Interesting, silencing B7-H4 by specific RNAi resulted in enhanced FasL expression and BEC apoptosis. Conversely, interruption of Fas\FasL interaction with using FasL blocking antibodies (clone 4H9) reversed cell apoptosis. Our results suggested that the intracellular B7-H4 appears to prevent Fas/FasL-mediated BEC apoptosis during the progression of PBC, and indicates B7-H4 is a possible target for therapeutic intervention of this disease.

Endothelial injury usually underlies the initial pathologic step of cardiovascular diseases. Primary endothelial cell (EC) apoptosis and secondary hyperproliferation both contribute to the development of atherosclerosis and luminal occlusion. In order to investigate the effects of resveratrol (RSV) on EC apoptosis, we applied high shear stress (HSS) with proinflammatory factors [tumor necrosis factor alpha (TNF-α) plus cycloheximide] to human pulmonary microvascular ECs (PMVECs) through an artificial capillary system. Intracellular reactive oxygen species (ROS) was measured by spectrofluorometry using dihydrorhodamine 123 fluorescent probe. Apoptosis and proliferation was determined by flow cytometric analysis. Protein expression was examined by Western blot. HSS plus inflammation significantly raised the ROS and the apoptosis level of PMVECs, which could be diminished by RSV pretreatment. In a 7-days incubation assay, RSV effectively inhibited the initial increase in apoptosis and thereby prevented subsequent PMVEC hyperproliferation induced by HSS plus inflammation. Mercaptosuccinate, a glutathione peroxidase (GPx-1) inhibitor or nicotinamide, a silent information regulator 2/sirtuin 1 (SIRT1) inhibitor could attenuate the antiapoptotic action of RSV on PMVECs; and RSV treatment upregulated GPx-1 and SIRT1 expression in PMVECs. In conclusion, RSV, probably by activating SIRT1 signaling pathway, inhibits the oxidative-stress-dependent phenotypical shift of ECs induced by HSS and proinflammatory factors in vitro.

Background: Deregulated thermal factors have been frequently implicated in the pathogenesis of male infertility, but the molecular basis through which certain responses are directed remain largely unknown. We previously reported that overexpression of exogenous Metastasis-associated protein 1 (MTA1) protects spermatogenic tumor cells GC-2spd (ts) against heat-induced apoptosis. To further dissect the underlying mechanism, we addressed here the fine coordination between MTA1 and p53 in pachytene spermatocytes upon hyperthermal stimulation., Methodology/principal Findings: High level of MTA1 expression sustained for 1.5 h in primary spermatocytes after heat stress before a notable decrease was detected conversely correlated to the gradual increase of acetylation status of p53 and of p21 level. Knockdown of the endogenous MTA1 in GC-2spd (ts) elevated the acetylation of p53 by diminishing the recruitment of HDAC2 and thereafter led to a dramatic increase of apoptosis after heat treatment. Consistent with this, in vivo interference of MTA1 expression in the testes of C57BL/6 mice also urged an impairment of the differentiation of spermatocytes and a disruption of Sertoli cell function due to the elevated apoptotic rate after heat stress. Finally, attenuated expression of MTA1 of pachytene spermatocytes was observed in arrested testes (at the round spermatid level) of human varicocele patients., Conclusions: These data underscore a transient protective effect of this histone modifier in primary spermatocytes against heat-stress, which may operate as a negative coregulator of p53 in maintenance of apoptotic balance during early phase after hyperthermal stress.

Integrins are a family of receptors for extracellular matrix proteins that have critical roles in human tissue development. Previous studies identified down-regulation and/or mutations of integrin alpha7 (ITGA7) in prostate cancer, liver cancer, soft tissue leiomyosarcoma, and glioblastoma multiforme. Here we report that expression of ITGA7 induced apoptosis in the human prostate cancer cell lines PC3 and DU145. Yeast two-hybrid analysis revealed that the C-terminus of ITGA7 interacts with high temperature requirement A2 (HtrA2), a serine protease with a critical role in apoptosis. Expression of ITGA7 increases the protease activity of HtrA2 both in vitro and in vivo. Deletion of the HtrA2 interaction domain abrogates the cell death activity of ITGA7, whereas down-regulation of HtrA2 dramatically reduced cell death mediated by ITGA7. In addition, site-directed protease-null mutant HtrA2S306A expression blocked apoptosis induced by ITGA7. Interestingly, interaction between ITGA7 and its ligand laminin 2 appears to protect against cell death, since depleting laminin beta2 with a small-interfering RNA significantly exacerbated apoptosis induced by ITGA7 expression. This report provides a novel insight into the mechanism by which ITGA7 acts as a tumor suppressor.

Increased lymphocyte apoptosis has been suggested to contribute to the development of systemic lupus erythematosus (SLE), but the critical factors involved in the apoptotic pathways are still unknown. By long serial analysis of gene expression (LongSAGE) profiles and microarray analyses, a novel apoptosis-related gene BclG(L) expression was found significantly increased in peripheral blood CD4+ T cells of SLE patients, which was correlated with the enhanced CD4+ T cells apoptosis, anti-nuclear antibody (ANA) titer and proteinuria. In vitro, BclG(L) expression could be specially upregulated by SLE serum stimulation and positively correlated with induced CD4+ T cell apoptosis. Enforcing BclG(L) overexpression by lentivirus could directly enhance CD4+ T cell apoptosis, but these apoptosis-inducing effects could be partially inhibited by knockdown of BclG(L) expression. Collectively, these results indicate that increased BclG(L) expression may contribute to the aberrant CD4+ T cell apoptosis which causes an inappropriate immune response and impaired homeostasis in SLE.

This study aimed at evaluating whether apoptosis of interstitial cells of Cajal (ICC), smooth muscle cells (SMC), and enteric neurons was involved in a guinea pig model of intestinal ischemia and reperfusion injury. The small intestinal segments were resected at either 6 (I60/R6h) and 12 h (I60/R12h) or 7 (I60/R7d) to 14 (I60/R14d) days after 60 min intestinal ischemia in the adult guinea pigs and studied by immunohistochemistry with anti-Kit, 5-bromo-2'-deoxyuridine (BrdU), alpha-smooth muscle actin, vimentin, and beta-tublin III antibodies. Also, apoptosis was tested by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. In the I60/R12h injury, there was a approximately 50% decrease of Kit+ cells in cell numbers at the level of myenteric plexus and a number of Kit-/vimentin-positive cells were labeled by TUNEL. Also, a few SMC and enteric neurons were TUNEL positive. The Kit+ ICC recovered to normal and a number of Kit-/BrdU-double-positive cells were observed in the I60/R14d group. Our results indicated that the intestinal I/R injury could lead to apoptosis of ICC, SMC, and enteric neurons which may contribute to the gastrointestinal motility disorders, and proliferation was involved in the recovery of ICC.

Although inhibition of cyclooxygenase-2 (COX-2) or activation of peroxisome proliferators-activated receptor gamma (PPAR-gamma) leads to growth inhibition in malignancies, the synergistic anti-tumor effects of combination of COX-2 inhibitor (NS-398) and PPAR-gamma agonist (rosiglitazone) on the human pancreatic cancer cells remains unknown. Here, we evaluated the effects of NS-398 and/or rosiglitazone on the cell proliferation and apoptosis in a pancreatic cancer cell line, SW1990. NS-398 and rosiglitazone decreased cell proliferation in a dose- and time-dependent manner. Proliferating cell nuclear antigen (PCNA) labeling index significantly decreased in the cells treated with either NS-398 or rosiglitazone. Both NS-398 and rosiglitazone alone induced apoptotic cell death of SW1990. The combination of NS-398 and rosiglitazone exerted synergistic effects on proliferation inhibition, and apoptosis induction in SW1990 cells, with down-regulation of Bcl-2 and up-regulation of Bax expression. Our results indicate that simultaneous targeting of COX-2 and PPAR-gamma inhibits pancreatic cancer development more effectively than targeting each molecule alone.

Background Aims: Endothelial apoptosis underlies the pathophysiology of pulmonary arterial hypertension (PAH). Some factors/cytokines released by endothelial progenitor cells (EPC) have been revealed as potent inhibitors of apoptosis. The aim of this study was to investigate the effects of EPC on pulmonary microvascular endothelial cell (PMVEC) survival with the PAH condition., Methods: PMVEC apoptosis was induced by high shear stress (HSS) with serum starvation or pro-inflammatory factors in an artificial capillary system. EPC were delivered into monocrotaline-induced PAH nude rats., Results: PMVEC apoptosis under HSS and serum starvation conditions was significantly inhibited by EPC conditioned medium (CM). It was attenuated by vascular endothelial growth factor (VEGF)-A or -B blocking. EPC CM promoted PMVEC proliferation, which was weakened by VEGF-A or interleukin (IL)-8 blocking. The EPC CM caused less apoptosis of PMVEC induced by HSS plus pro-inflammatory factors. The anti-apoptotic effect of EPC CM was attenuated by blockade of either vascular endothelial growth factor receptor (VEGFR)-1 or -2. However, the pro-proliferating effect appeared to be weakened only by VEGFR-2 blocking. Both Erk1/2 and Akt phosphorylation were enhanced by EPC CM. VEGFR-2 blockage led to significant inhibition of Erk1/2 and Akt activation; VEGFR-1 blockage only of Erk1/2 activation. Human-origin VEGF co-localized with incorporated EPC in small pulmonary arterioles, and EPC transplantation resulted in down-regulation of caspase-3 expression., Conclusions: The VEGF-A/B-VEGFR-1/2-Erk1/2 signal pathway took major responsibility for the anti-apoptotic effects of EPC on PMVEC, and VEGF-A-VEGFR-2-Akt for pro-proliferating effects. Growth factors, secreted in a paracrine manner by transplanted EPC, inhibited cell apoptosis in PAH lung.

Aim: The recruitment of endothelial progenitor cells (EPC) to ischemia has recently been suggested as an important mechanism of tissue repair. Although tissue ischemia can facilitate EPC mobilization, recruitment, and retention at the hypoxic site, the effects of hypoxia on EPC survival are not well known. In the present study, we examined whether hypoxia (2% O2) would suppress apoptosis induced by serum withdrawal and whether survival signals, such as the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated protein kinase (ERK) pathways, were involved in this process., Methods: After being serum-starved for 24 h, EPC were cultured under normoxic or hypoxic conditions (2% O2) for 24 h. Cell survival was assessed by 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, annexin V-propidium iodide dual-color flow cytometry, and terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling assay. The expressions of signaling proteins were evaluated by Western blot analysis., Results: Under hypoxic conditions, EPC were resistant to apoptosis induced by serum starvation. The inhibition of the PI3K/Akt pathway using the LY294002 inhibitor prevented hypoxia-inhibited apoptosis in EPC and altered the phosphorylation state of glycogen synthase kinase-3beta, an effector protein involved in regulation of EPC apoptosis. However, ERK inhibitor PD98059 had no significant effect on cell survival., Conclusion: Our data demonstrated that hypoxia inhibited serum withdrawal-induced apoptosis in EPC, which might be associated with the activation of the PI3K/Akt pathway.

AIM: To investigate the inhibitory effect of the combined use of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and oridonin on choroidal melanoma cell lines, and to explore its underlying mechanism. METHODS: MUM-2B and C918 cells were treated with different concentrations of TRAIL and oridonin, and MTT assay used to evaluate the inhibition rate of the two compounds on cells. Then, the cell cycle distribution and apoptosis were detected by flow cytometry, and changes in apoptosis-related proteins such as death receptor 5 (DR5), a-caspase-3, and x-linked inhibitor of apoptosis protein (XIAP) were detected by Western blot. MUM-2B cells were transfected with si-DR5, which interfered with the expression of the DR5 gene. MTT and Western blot assay were used to detect cell activity and apoptosis-related proteins. RESULTS: When TRAIL and oridonin were simultaneously administered to the MUM-2B cells, the apoptosis rate was significantly higher than that by the two drugs individually. However, the effect of combined use of TRAIL and oridonin on C918 cells was not significantly different from that used alone. Cell cycle analysis showed that TRAIL and oridonin could induce G2/M arrest in MUM-2B cells. The Western blot results showed that the protein expression levels of the DR5, a-caspase-3, and BAX increased, while the expression levels of the anti-apoptosis-related proteins XIAP and BCL-2 were suppressed when TRAIL and oridonin simultaneously administered to MUM-2B cells. Interfering the expression of DR5 gene in MUM-2B cells could reverse the inhibitory effect of oridonin and TRAIL on the proliferation and apoptosis induction of MUM-2B cells. CONCLUSION: The inhibitory effects of oridonin and TRAIL on MUM-2B cells are significantly enhanced when they were administered as a combined treatment, which may ascribe to up-regulation of DR5.

Abstract Background The mechanism of podocyte apoptosis is not fully understood. In addition, the role of the inositol 1,4,5-triphosphate receptor (IP3R)/glucose-regulated protein 75 (Grp75)/voltage-dependent anion channel 1 (VDAC1)/mitochondrial calcium uniporter (MCU) calcium regulation axis, which is located at sites of endoplasmic reticulum (ER) mitochondria coupling, in the mechanism of podocyte apoptosis is unclear. This study aimed to understand the roles of this axis in podocyte apoptosis and explore potential targets for podocyte protection. Methods The expression of IP3R, Grp75, VDAC1, and MCU and mitochondrial Ca2+ were analyzed during Adriamycin- or angiotensin II-induced apoptosis in cultured mouse podocytes. The interaction between IP3R, Grp75, and VDAC1 was investigated using co-immunoprecipitation experiments. The effects of IP3R, Grp75, and MCU agonists and antagonists on mitochondrial Ca2+ and apoptosis were investigated in cultured podocytes. The podocyte-protective effects of an MCU inhibitor were further investigated in rats with Adriamycin-induced nephropathy. Results Increased expression of IP3R, Grp75, VDAC1 and MCU, enhanced interaction among the IP3R-Grp75-VDAC1 complex, mitochondrial Ca2+ overload, and increased active caspase-3 levels were confirmed during Adriamycin- or angiotensin II-induced mouse podocyte apoptosis. Agonists of this axis facilitated mitochondrial Ca2+ overload and podocyte apoptosis, whereas specific antagonists against IP3R, Grp75, or MCU prevented mitochondrial Ca2+ overload and podocyte apoptosis. A specific MCU inhibitor prevented Adriamycin-induced proteinuria and podocyte foot process effacement in rats. Conclusions This study identified a novel pathway in which the IP3R-Grp75-VDAC1-MCU calcium regulation axis mediated podocyte apoptosis by facilitating mitochondrial Ca2+ overload. Antagonists that inhibit Ca2+ transfer from ER to mitochondria protected mouse podocytes from apoptosis. An MCU inhibitor protected podocytes and decreased proteinuria in rats with Adriamycin-induced nephropathy. Therefore, antagonists to this pathway have promise as novel podocyte-protective drugs.

A colon tumor, one of the digestive tract malignant tumors, is harmful to human health. A potential new treatment still deserves attention. The development of a new drug needs more resources, including time and expense. Therefore, the old drug with new targets has become a current research hotspot. Fluvoxamine, as an antidepressant, could play an effect on inhibiting 5‐hydroxytryptamine reuptake. In the present research, the antitumor effects and possible mechanisms of fluvoxamine are validated. The results showed that fluvoxamine significantly suppressed the migration and proliferation of tumor cells, and increased the apoptosis in vitro. Additionally, fluvoxamine significantly delays tumor development, and prompts the apoptosis in tumor tissues of mice‐burdened colon tumors in vivo. The tumor suppression might be related with that fluvoxamine inhibits the expression of phosphorylated signal transducer and activator of transcription 3, matrix metalloproteinase 2, and cleaved‐caspase 3. Importantly, fluvoxamine significantly reduces the expression level of programmed cell death ligand 1. This could be a possible reason that treatment with fluvoxamine drives the infiltration of T lymphocytes and M1‐type macrophages in tumor tissues. Taken together, this research suggests that fluvoxamine might be a promising drug to treat colon cancer by inhibiting the proliferation and migration, inducing apoptosis, and even increasing the immune response of antitumor. [ABSTRACT FROM AUTHOR]

Backgrounds: Autophagy is an important process in the pathogenesis of diabetes and plays a critical role in maintaining cellular homeostasis. However, the autophagic response and its mechanism in diabetic vascular endothelium remain unclear. Methods and Results: We studied high-glucose-induced renin-angiotensin system (RAS)-mitochondrial damage and its effect on endothelial cells. With regard to therapeutics, we investigated the beneficial effect of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs) against high-glucose-induced endothelial responses. High glucose activated RAS, enhanced mitochondrial damage and increased senescence, apoptosis and autophagic-responses in endothelial cells, and these effects were mimicked by using angiotensin II (Ang). The use of an ACEI or ARB, however, inhibited the negative effects of high glucose. Direct mitochondrial injury caused by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) resulted in similar negative effects of high glucose or Ang and abrogated the protective effects of an ACEI or ARB. Additionally, by impairing autophagy, high-glucose-induced senescence and apoptosis were accelerated and the ACEI- or ARB-mediated beneficial effects were abolished. Furthermore, increases in FragEL™ DNA Fragmentation (TUNEL)-positive cells, β-galactosidase activation and the expression of autophagic biomarkers were revealed in diabetic patients and rats, and the treatment with an ACEI or ARB decreased these responses. Conclusions: These data suggest that autophagy protects against senescence and apoptosis via RAS-mitochondria in high-glucose-induced endothelial cells.

Intervertebral disc degeneration (IDD) disease has been considered as the main cause of low back pain (LBP), which is a very common symptom and the leading cause of disability worldwide today. The pathological mechanism of IDD remains quite complicated, and genetic, developmental, biochemical, and biomechanical factors all contribute to the development of the disease. There exists no effective, non‐surgical treatment for IDD nowadays, which is largely related to the lack of knowledge of the specific mechanisms of IDD, and the lack of effective specific targets. Recently, non‐coding RNA, including miRNA, has been recognized as an important regulator of gene expression. Current studies on the effects of miRNA in IDD have confirmed that a variety of miRNAs play a crucial role in the process of IDD via nucleus pulposus cells (NPC) apoptosis, abnormal proliferation, inflammatory factors, the extracellular matrix (ECM) degradation, and annulus fibrosus (AF) degeneration. In the past 10 years, research on miRNA has been quite active in IDD. This review summarizes the current research progression of miRNA in the IDD and puts forward some prospects and challenges on non‐surgical treatment for IDD. [ABSTRACT FROM AUTHOR]