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Objective. Gastric cancer, one of the most common malignant tumors worldwide, arises from the gastric mucosal epithelium and severely affects patient health and quality of life. Luteolin (LUT) is a flavonoid found in vegetables and fruits with diverse functions. A large number of studies have confirmed that LUT has an antitumor effect. Therefore, this study is aimed at verifying whether LUT can exert antitumor effects in synergy with oxaliplatin (OXA). As such, we examined the effects of LUT, OXA, and their coadministration in a gastric adenocarcinoma cell line (SGC-7901). We used the MTT assay to quantify the proliferation of SGC-7901 cells, flow cytometry to detect the cell cycle and apoptosis, ELISA to detect the expression of cell-cycle-related proteins, and western blot to detect the expression of related apoptotic factors. The results of this study show that the combination of LUT and OXA inhibited SGC-7901 cell proliferation and induced apoptosis by altering cell-cycle proportions. In addition, the combination also activated Cyt c/caspase signaling in SGC-7901 cells. In summary, LUT synergy with OXA inhibited the proliferation of gastric cancer cells in vitro. The present study also elucidated the mechanism by which LUT potentiated the sensitivity of SGC-7901 cells to OXA through the Cyt c/caspase pathway. [ABSTRACT FROM AUTHOR]

Chrysophanol is an anthraquinone compound, which exhibits anticancer effects on certain types of cancer cells. However, the effects of chrysophanol on human breast cancer remain to be elucidated. The aim of the present study was to clarify the role of chrysophanol on breast cancer cell lines MCF‑7 and MDA‑MB‑231, and to identify the signal transduction pathways regulated by chrysophanol. MTT assay and flow cytometric analysis demonstrated that chrysophanol inhibited cell proliferation, and cell cycle progression in a dose‑dependent manner. The expression of cell cycle‑associated cyclin D1 and cyclin E were downregulated while p27 expression was upregulated following chrysophanol treatment at the mRNA, and protein levels. The Annexin V/propidium iodide staining assay results revealed that apoptosis levels increased following chrysophanol treatment. Chrysophanol upregulated caspase 3 and poly (ADP‑ribose) polymerase cleavage in both cell lines. Furthermore, chrysophanol enhanced the effect of paclitaxel on breast cancer cell apoptosis. In addition, chrysophanol downregulated apoptosis regulator Bcl‑2 protein, and transcription factor p65 and IκB phosphorylation. Inhbition of nuclear factor (NF)‑κB by ammonium pyrrolidine dithiocarbamate diminished the effect of chrysophanol on apoptosis and associated proteins. In conclusion, the results of the current study demonstrated that chrysophanol effectively suppresses breast cancer cell proliferation and facilitates chemosentivity through modulation of the NF‑κB signaling pathway. [ABSTRACT FROM AUTHOR]

Key message: Oxidative stress and apoptosis-like programmed cell death, induced in part by H O , are two key factors that damage cells during plant cryopreservation. Their inhibition can improve cell viability. Abstract: We hypothesized that oxidative stress and apoptosis-like event induced by ROS seriously impact plant cell viability during cryopreservation. This study documented changes in cell morphology and ultrastructure, and detected dynamic changes in ROS components (O, HO and OH·), antioxidant systems, and programmed cell death (PCD) events during embryonic callus cryopreservation of Agapanthus praecox. Plasmolysis, organelle ultrastructure changes, and increases in malondialdehyde (a membrane lipid peroxidation product) suggested that oxidative damage and PCD events occurred at several early cryopreservation steps. PCD events including autophagy, apoptosis-like, and necrosis also occurred at later stages of cryopreservation, and most were apoptosis. HO is the most important ROS molecule mediating oxidative damage and affecting cell viability, and catalase and AsA-GSH cycle are involved in scavenging the intracellular HO and protecting the cells against stress damage in the whole process. Gene expression studies verified changes of antioxidant system and PCD-related genes at the main steps of the cryopreservation process that correlated with improved cell viability. Reducing oxidative stress or inhibition of apoptosis-like event by deactivating proteases improved cryopreserved cell viability from 49.14 to 86.85 % and 89.91 %, respectively. These results verify our model of ROS-induced oxidative stress and apoptosis-like event in plant cryopreservation. This study provided a novel insight into cell stress response mechanisms in cryopreservation. [ABSTRACT FROM AUTHOR]

Tyroserleutide (YSL) is an active, low-molecular-weight polypeptide with in vitro and in vivo anticancer effects on human hepatocellular carcinoma BEL-7402 cells. In this study, we studied the effects of YSL on PI3K/AKT in the BEL-7402 cells to explore its anti-tumor mechanism. Results showed that YSL could up-regulate the mRNA and protein expression of tumor suppressor PTEN and increase their activities, meanwhile inhibited the mRNA and protein expression of oncogene AKT and decreased the kinase activities of AKT and PDK1. The resuming balance effect of YSL between PTEN and AKT could prevent the transmission of tumor cell proliferation signals in the PI3K/AKT pathway. Inhibition of AKT would change the status of downstream effectors in the PI3K/AKT pathway: (1) inhibition of AKT up-regulated expression of cell cycle regulatory factors of downstream - P21 and P27 which repressed cell cycle and inhibited proliferation of tumor cells. (2) Inhibition of AKT decreased the phosphorylation level of MDM2, and then increased the protein level of P53 which would accelerate death proceeding of tumor cells. (3) Inactivation of AKT removed its inhibition effect on phosphorylation of Bad, which might decrease protein level of apoptosis inhibitor Bcl-2 and Bcl-XL, damaging mitochondria of tumor cells and inducing apoptosis. [ABSTRACT FROM AUTHOR]

Abstract: Endocrine glands-derived vascular endothelial growth factor (EG-VEGF, also termed as Prok1)—a novel cytokine that selectively acts on the endothelial cells of endocrine glands—was recently reported to be involved in the regulation of tumor cell growth and survival. However, its roles in the regulation of pancreatic cancer progression remain unclear. In this report, we investigated the suppressive effects of EG-VEGF on pancreatic cancer cell apoptosis and the relevant mechanisms. By using reverse-transcriptase polymerase chain reaction (RT-PCR) we found that the Mia PaCa II cells of the pancreatic cancer cell line express the mRNAs of both EG-VEGF (Prok1) and its receptors. EG-VEGF protects pancreatic cancer cells from apoptosis through upregulation of myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic protein of the bcl-2 family. Treatment of pancreatic cancer cells with EG-VEGF results in the rapid phosphorylation of mitogen-activated protein kinase (MAPK), STAT3, and AKT, which are involved in the upregulation of Mcl-1 expression. EG-VEGF (Prok1) protects Mia PaCa II cells from apoptosis through G protein-coupled receptor (GPR)-induced activation of multiple signal pathways, and hence can be a novel target for pancreatic cancer therapy. [Copyright &y& Elsevier]

Aim: Sphingomyelin phosphodiesterase 1 (SMPD1) plays an essential role in initiating the female germ cell death signal. To evaluate whether RNA interference has potential as a new approach in germ cell protection, we tested the effect of SMPD1 knockdown on human granulosa cells in vitro. Methods: We designed and synthesized three small interference RNA (siRNA) sequences targeted on SMPD1 and transfected them into human luteinizing granulosa cells (hGC) in vitro. Forty-eight hours after transfecting with siRNAs, hGC were treated with mitomycin C (MMC) to induce apoptosis. mRNA was detected with quantitative RT-PCR and protein was detected with Western blot. Methyl thiazolyl tetrazolium (MTT) assay was used to measure cell survival rate and detection of apoptotic rate of cells with Annexin V-PI staining by flow cytometer (FCM). Study groups were compared with liposome (lipofectamine 2000), MMC control and negative control siRNA. Results: After treatment with siRNA targeted to SMPD1, significant SMPD1 suppression occurred. After knockdown expression of SMPD1, the survival rate of hGC increased from 32.3% to 40.3%, and the apoptosis rate decreased from 68.3% to 44%. Conclusion: siRNA targeted on SMPD1 can protect hGC cells from apoptosis. These results reveal SMPD1 as a significant and effective target site for RNAi in the protection of human germ cells, which may have a direct bearing on future therapeutic research. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS) is mainly characterized by the activation of inflammatory cells and chronic inflammatory responses after cell injury. Pyroptosis is a form of programmed cell death (PCD) accompanied by the release of inflammatory factors. Many studies have shown that pyroptosis plays an important role in AS. Increasing evidence also indicates that long non-coding RNA H19 (lncRNA H19) involved in AS. However, whether the role of lncRNA H19 in AS is related to pyroptosis and the underlying mechanisms are largely unknown. In this study, we found that oxidized low-density lipoprotein (ox-LDL) induced pyroptosis and decreased the expression of lncRNA H19 in Raw 264.7 cells. Besides, silencing endogenous lncRNA H19 increased inflammatory responses and pyroptosis while exogenous overexpression of lncRNA H19 reversed this effect. Notably, we identified that the inhibitor of caspase-1 (XV-765) completely abrogated the silencing endogenous lncRNA H19 mediated pyroptosis. In addition, we found that lncRNA H19 inhibited ox-LDL-induced activation of nuclear factor-kappa B (NF-κB), mitochondrial dysfunction, and reduced the production of reactive oxygen species (ROS). Moreover, VX-765 impaired the silencing endogenous lncRNA H19 mediated pyroptosis. Overall, these findings indicated that lncRNA H19 may play an important role in pyroptosis and may serve as a potential therapeutic target for AS. [ABSTRACT FROM AUTHOR]

• Cucurbitacin IIb (CuIIb) exhibited the proliferation inhibitory activity in A549 cells. • CuIIb induced apoptosis via STAT3 pathway. • CuIIb suppressed the cell cycle and resulted G2/M phase cell cycle arrest. • Leu694 and Met769 are key amino acids for EGFR-CuIIb binding. • CuIIb inhibited the kinase activity of EGFR and may serve as a potential EGFR TKI. Epidermal growth factor receptor (EGFR) is considered as a valid target in the clinical trials of anticancer therapy and tyrosine kinase inhibitors (TKIs) of EGFR are approved for cancer treatments. In present work, cucurbitacin IIb (CuIIb) was confirmed to exhibit the proliferation inhibitory activity in A549 cells. CuIIb induced apoptosis via STAT3 pathway, which was mitochondria-mediated and caspase-dependent. CuIIb also suppressed the cell cycle and induced G2/M phase cell cycle arrest. CuIIb was capable of suppressing the signal transmitting of the EGFR/mitogen-activated protein kinase (MAPK) pathway which was responsible for the apoptosis and cell cycle arrest. Homogeneous time-resolved fluorescence (HTRF) analysis demonstrated that the kinase activity of EGFR was inhibited by CuIIb. Molecular docking suggested that the CuIIb-EGFR binding fundamentally depends on the contribution of both hydrophobic and hydrogen-bonding interactions. Hence CuIIb may serve as a potential EGFR TKI. [ABSTRACT FROM AUTHOR]

As a polyphenolic compound, resveratrol (Res) is widely present in a variety of plants. Previous studies have shown that Res can inhibit various tumors. However, its role in c remains largely unexplored. In the present study, we first demonstrated that Res inhibited cell viability and induced apoptosis of glioblastoma A172 cell. Further experiments showed that Res induced mitochondrial dysfunction and activated the activity of caspase‐9. Functional studies have found that Res treatment is associated with an increase in the expression of Pak2. Interestingly, inhibition of Pak2 could further augment the proapoptotic effect of Res. Mechanistically, Pak2 inhibition induced reactive oxygen species overproduction, mitochondria‐JNK pathway activation, and AMPK‐YAP axis suppression. However, overexpression of YAP could abolish the anticancer effects of Res and Pak2 inhibition, suggesting a necessary role played by the AMPK‐YAP pathway in regulating cancer‐suppressive actions of Res and Pak2 inhibition. Altogether, our results indicated that Res in combination with Pak2 inhibition could further enhance the anticancer property of Res and this effect is mediated via the AMPK‐YAP pathway. [ABSTRACT FROM AUTHOR]

• An anti-leukemia polysaccharide (APS-2I) was isolated from Chinese Angelica root. • The APS-2I digested fraction (G-4) exhibits higher anti-leukemia effect than APS-2I in vitro and vivo. • APS-2I and G-4 bind to Gal-3 with Kd of 9.35 ± 0.3 μM and 1.97 ± 0.7 μM respectively. • Backbone of APS-2I contains 1,4-Gal p A, 1,4-Gal p 6Me,1,3-Rha p , 1,2,6-Man p, 1,6-Gal p and 1,2-Man p. • Branches of APS-2I contains T-Ara f, 1,4-Gal p , 1,3-Ara f , 1,5-Ara f and 1,3,5-Ara f , 1,6-Gal p. Galectin-3 (Gal-3) is a potential target for acute myeloid leukemia therapeutics which contains a carbohydrate-recognition domain. However, the development of polysaccharide inhibitors against Gal-3 is insufficient. In this research, we found a polysaccharide from Angelica sinensis (Oliv.) Diels, named APS-2I, that can bind to Gal-3 with dissociation constant (Kd) of 9.35 ± 0.3 μM and activate the intrinsic apoptosis pathways to induce leukemia cells apoptosis. APS-2I is a homogeneous polysaccharide with a molecular weight of 7.2 × 105 Da, that composes of mannose, rhamnose, galacturonic acid, glucose, galactose and arabinose with a ratio of 4:5:1:10:23:39. In addition, a galactosidase digested fraction of APS-2I named G-4 showed higher affinity to Gal-3 with the Kd of 1.97 ± 0.7 μM and higher apoptosis inducing effect on leukemia cells, which demonstrated that G-4 contains the bio-active structural region of APS-2I. This study provides effective basis for structural analysis and the anti-leukemia mechanism of Angelica polysaccharide APS-2I. [ABSTRACT FROM AUTHOR]

Background: Chronic alcohol intake increases circulating endotoxin levels causing excessive inflammation that aggravates the liver injury. (E)‐2,3‐dimethoxy‐4′‐methoxychalcone (L6H21), a derivative of chalcone, has been found to inhibit inflammation in cardiac diseases and nonalcoholic fatty liver disease. However, the use of L6H21 in alcoholic liver disease to inhibit exotoxin‐associated inflammation has not been explored. In this study, we examined the effects of L6H21 on EtOH + LPS‐induced hepatic inflammation, steatosis, and liver injury and investigated the underlying mechanisms. Methods: C57BL6 mice were treated with 5% EtOH for 10 days, and LPS was given to the mice 6 hours before sacrificing. One group of mice was supplemented with L6H21 with EtOH and LPS. RAW264.7 cells were used to analyze the effects of L6H21 on macrophage activation. Results: EtOH + LPS treatment significantly increased hepatic steatosis and serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), which were reduced by L6H21 treatment. EtOH + LPS treatment increased hepatic inflammation, as shown by the increased hepatic protein levels of Toll‐like receptor‐4, p65, and p‐IκB, and increased oxidative stress, as shown by protein carbonyl levels and reactive oxygen species formation, which were reduced by L6H21 treatment. In addition, L6H21 treatment markedly inhibited EtOH + LPS‐elevated hepatic protein levels of NLRP3, cleaved caspase‐1, cleaved IL‐1β, and caspase‐1‐associated apoptosis. Conclusions: Our results demonstrate that L6H21 treatment inhibits EtOH + LPS‐induced liver steatosis and injury through suppression of NLRP3 inflammasome activation. L6H21 may be used as an alternative strategy for ALD prevention/treatment. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is characterized by reproductive, endocrine, and metabolic disorders. Icariin has been shown to regulate endocrine and metabolic imbalances. This study aimed to determine the therapeutic effect and pharmacological mechanism of icariin in PCOS rats. Rats were fed a high-fat diet and gavaged with letrozole to induce PCOS. Thirty-six female rats were randomly divided into four groups: control, model, low-dose, and high-dose icariin. After 30 days of treatment, we evaluated the therapeutic effects on weight and diet, sex hormone levels, ovarian morphology, estrous cycle, inflammatory factors, and indicators of glucolipid metabolism. Combined with the ovarian transcriptome, we verified the key markers of apoptosis and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway by RT-qPCR for mRNA level, western blot, and immunohistochemistry for protein expression. Icariin significantly improved ovarian function and reproductive endocrine disorders by regulating sex hormones, restoring the estrous cycle, and reducing ovarian morphological damage in PCOS rats. Icariin-treated rats had lower weight gain and reduced triglycerides, fasting insulin, HOMA-IR, TNF-α, and interleukin-6 with higher high-density lipoprotein cholesterol levels than PCOS rats. TUNEL staining showed icariin improved apoptosis in the ovaries. This was supported by an increase in Bcl2 and a decrease in Bad and Bax. Icariin decreased the ratios of p-JAK2/JAK2, p-STAT1/STAT1, p-STAT3/STAT3, and p-STAT5a/STAT5a, decreased IL-6, gp130 expression, and increased cytokine-inducible SH2-containing protein (CISH) and suppressor of cytokine signaling 1 (SOCS1) expression. The pharmacological mechanism may be related to the reduction in ovarian apoptosis and inhibition of the IL-6/gp130/JAK2/STATs pathway. [ABSTRACT FROM AUTHOR]

Glutamate and γ‑aminobutyric acid (GABA) transporters serve central roles in normal neuronal activity and are associated with numerous pathological brain conditions, including ischemia and epilepsy. However, the interplay between these transporters in ischemia remains unclear. In the present study, the expression levels of the excitatory amino acid carrier 1 (EAAC1) and GABA transporter 1 (GAT1) were analyzed in vivo and in vitro within ischemic models by immunofluorescence, western blot and RT‑qPCR. Cell survival rates were analyzed following altered expression of these transporters within neuronal cells by flow cytometry. Expression levels of EAAC1 were reduced within the cerebrum of focal cerebral ischemic middle cerebral artery occlusion rat models as well as in primary neurons cultured under hypoxia. However, GAT1 expression levels were slightly elevated under ischemic conditions. The altered expression levels of EAAC1 and GAT1 were combined within neuron cells and the effects were investigated. Apoptotic analysis revealed that EAAC1 suppression and overexpression of GAT1 increased neuronal cell apoptosis under hypoxic conditions; however, EAAC1 overexpression combined with GAT1 knockdown reduced neuronal cell apoptosis under hypoxic conditions. The present study detected the expression levels of the glutamate and GABA transporters under hypoxia, in association with ischemia. The results indicated that, increased expression of EAAC1 combined with GAT1 suppression may provide protective effects in the treatment of epilepsy and ischemia. [ABSTRACT FROM AUTHOR]

We established both an acute and chronic cardiac toxicity rat model, which showed pretreatment with rutin attenuated pirarubicin-induced myocardial histopathological injury, electrocardiogram abnormalities, and cardiac dysfunction. Rutin also significantly reduced serum levels of MDA, BNP, CK-MB, CTnT, and LDH and increased serum SOD levels. Treatment with rutin and dexrazoxane resulted in an increase in Bcl-2/Bax ratio (p < 0.05) and reduction in JNK and Caspase-3 protein levels, compared to the pirarubicin group (all p < 0.05). Furthermore, rutin at a dose of 50 mg/kg significantly attenuated the above-mentioned alterations. Our study suggests the antioxidant and anti-apoptotic properties of rutin may be responsible for the cardioprotective effects observed. [ABSTRACT FROM AUTHOR]

Cerebral ischemic stroke has long been recognized as a prevalent and serious neurological disease that was associated with high mortality and morbidity. However, the current therapeutic protocols remain suboptimal with major mechanisms underlying stroke urgently warranted. Inhibitor of DNA binding/differentiation 2 (Id2) is found to be up-regulated in neuronal cells following hypoxia/ischemia (H/I). This study was aimed to investigate whether knockdown of Id2 in neuronal cells could protect them from hypoxic and ischemic injury both in vitro and in vivo . Flow cytometric analysis was employed to assess neuronal apoptosis in CoCl 2 -treated neuroblastoma B35 cells engineered to overexpress or knockdown Id2 expression. In vivo knockdown of Id2 was performed in Sprague-Dawley rats by a single intracerebroventricular injection of Cy3-labeled and cholesterol-modified Id2-siRNA. We found that knockdown of Id2 attenuated H/I-induced neuronal apoptosis in vitro while overexpression of Id2 produced an opposite effect. In a rat model of middle cerebral artery occlusion (MCAO), in vivo knockdown of Id2 significantly improved neurological deficits, reduced the volume of ischemic infarction and diminished the neuronal apoptosis in the penumbra area. Double immunofluorescence staining showed less co-localization of retinoblastoma tumor suppressor protein (Rb)-Id2 but greater co-localization of Rb-E2F1 in the penumbra area. Cell cycle assay further demonstrated that Id2 knockdown induced G0/G1 cell cycle arrest in CoCl 2 -treated B35 cells. The present data support the implication of Id2 in the modulation of H/I-induced neuronal apoptosis and may provide a potential therapeutic option to protect brain tissues from ischemic injury by inhibition of its expression. [ABSTRACT FROM AUTHOR]

Highlights: [•] Id2 mRNA and protein are up-regulated in neuronal cells in vivo and in vitro. [•] The increased expression of Id2 might be associated with neuronal apoptosis. [•] The up-regulation of Id2 is consistent with the enhanced expression of Bax. [•] Co-localization of Id2, TUNEL and NeuN was observed in ischemic neurons. [ABSTRACT FROM AUTHOR]

Abstract: Inhibition of the forkhead transcription factor, FOXO3a, can promote the transition from primordial to primary follicle and subsequent follicle development in mammalian ovaries. Stem cell factor (SCF) initiates anti-apoptotic signaling from its membrane receptor, c-kit, to Bcl-2 family members through PI3K/AKT in oocytes of primordial follicles. However, whether FOXO3a mediates the apoptosis of naked oocytes and oocytes of primordial follicles remains unknown. In the present study, oocytes from nests and primordial follicles from neonatal rat ovaries were cultured, and oocyte apoptosis was examined using the TUNEL technique. The pro-apoptotic action of FOXO3a and the potential signal transduction pathways were investigated using RT-PCR, Western blot, and immunocytochemistry. Culturing oocytes in the presence of SCF did not affect the level of total FOXO3a protein, but rapidly elevated the level of phosphorylated FOXO3a (indicating functional suppression). As phosphorylated FOXO3a increased, oocyte apoptosis was inhibited. The specific PI3K/Akt inhibitor, LY 294002, abolished the phosphorylation of FOXO3a and the anti-apoptotic action of SCF. SCF down-regulated the expression of p27KIP1 and pro-apoptotic factors such as Bim, Bad, and Bax, and this activity was reversed by LY 294002. SCF up-regulated the expression of MnSOD, which was also inhibited by LY 294002. However, SCF had no effect on Bcl-2 protein. These results suggest that FOXO3a is involved in oocyte apoptosis in the neonatal rat ovary, and the SCF-PI3K/Akt-FOXO3a signaling pathway mediates oocyte apoptosis and primordial follicle formation. [Copyright &y& Elsevier]

Esophageal squamous cell carcinoma (ESCC) is one of the most debilitating and invasive tumors. Although previous reports have demonstrated the critical role microRNA-181a (miR-181a) serves in the progression of ESCC, how miR-181a induces epithelial-mesenchymal transition (EMT) remains to be elucidated. In the present study, the expression profiles of TGF-β1 and Smad4 proteins in 88 patients with ESCC and 21 adjacent non-cancerous tissues were analyzed using immunohistochemistry. The expression of miR-181a in ESCC cells (ECA109 and TE-1) and HEEC was analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The role of miR-181a in ESCC was analyzed using miR-181a mimics and inhibitor in the same system. Migration, proliferation and apoptosis of cells were assessed using wound-healing assays and cell proliferation assays and flow cytometry, respectively. The expression levels of TGF-β1 and Smad4 in ESCC cell lines transfected with miR-181a mimics and inhibitor were measured using RT-qPCR and western blotting. The expression of E-cadherin and vimentin was also assessed following transfection. The findings demonstrated that expression of TGF-β1 was upregulated, in contrast to Smad4 expression which was downregulated. Expression levels of Smad4 affected the prognosis of patients with ESCC. Higher expression of miR-181a promoted migration and proliferation but inhibited apoptosis of ESCC cells. miR-181a promoted EMT by modulating Smad4 expression in ESCC cells. Overall, these findings revealed that miR-181a induced EMT in ESCC via the TGF-β/Smad pathway in ESCC. Consequently, miR-181a is a potential novel target against ESCC. [ABSTRACT FROM AUTHOR]