Steroidal saponin SSPH I induces ferroptosis in HepG2 cells via regulating iron metabolism.

Hepatocellular carcinoma (HCC) is a common type of solid liver carcinoma. Regulating ferroptosis is important for the treatment of HCC. SSPH I is an anti-HCC steroidal saponin isolated from Schizocapsa plantaginea Hance. In this study, we found that SSPH I exerted significant anti-proliferation and anti-migration effects on HepG2 cell, ferroptosis inhibitor ferrostatin-1 or iron chelator ciclopirox partly attenuated the effect of SSPH I. SSPH I also induced apoptosis and G2/M phase cell cycle arrest. ROS accumulation, glutathione depletion and malondialdehyde accumulation were detected after SSPH I treatment, which leads to lipid peroxidation. Ferrostatin-1 or ciclopirox showed a significant antagonist effect towards SSPH I induced lipid peroxidation. Furthermore, typical morphologic changes of ferroptosis, such as increasing density of mitochondrial membrane and reduction of mitochondrial cristae were observed in HepG2 cells after SSPH I treatment. SSPH I does not regulate the xCT protein. Interestingly, SSPH I elevated the expression levels of SLC7A5, which is the negative regulator of ferroptosis. In contrast, SSPH I upregulated the expression of TFR and Fpn proteins, leading to the accumulation of Fe2+. Ferrostatin-1 and ciclopirox presented a similar antagonist effect on SSPH I. In conclusion, our research first reveals that SSPH I induced ferroptosis in HepG2 cells. In addition, our results suggest that SSPH I induces ferroptosis by causing iron overload in HepG2 cells.

Prognostic value of PD-L1 and Siglec-15 expression in patients with nasopharyngeal carcinoma.

Sialic acid-binding immunoglobulin-like lectin 15 (Siglec-15) might be involved in the activation of important pathways related to tumor immune escape, along with programmed death-ligand 1 (PD-L1). Here, we aimed to investigate the correlation between the expression of Siglec-15 and PD-L1 in nasopharyngeal carcinoma (NPC) patients. We determined the expression of PD-L1 via immunohistochemical staining and that of Siglec-15 via immunofluorescence staining in 182 NPC tissue samples. A significant correlation was identified between the PD-L1 and Siglec-15 expression (P = 0.000). Moreover, Kaplan-Meier survival curves showed that PD-L1 expression was associated with improved overall survival (OS) (P = 0.025) and Siglec-15 expression was associated with improved distant failure-free survival (D-FFS) (P = 0.048). Moreover, multivariate Cox analysis showed that PD-L1 and Siglec-15 were independent predictors of OS (P = 0.020) and D-FFS (P = 0.047), respectively. The results of the log-rank test and Cox regression analyses showed that patients exhibiting no PD-L1/Siglec-15 expression had significant advantages regarding OS, compared to other groups (P = 0.037). PD-L1 and Siglec-15 may represent novel biomarkers for predicting the prognosis of NPC patients. Siglec-15 may be considered as a potential target for the development of therapeutics for NPC treatment in the future.

LRP11-AS1 promotes the proliferation and migration of triple negative breast cancer cells via the miR-149-3p/NRP2 axis.

BACKGROUND: Breast cancer is the most commonly diagnosed cancer in women. Triple negative breast cancer (TNBC) is the most difficult subtype of breast cancer to treat due to the deficiency in drug-targetable receptors. LRP11-AS1, a newly identified oncogenic long noncoding RNA (lncRNA) was found to be significantly overexpressed in TNBC cells. The aim of this study is to investigate the malignant roles and the oncogenic mechanisms of LRP11-AS1 in TNBC. METHODS: CCK-8, colony formation, transwell migration and transwell invasion assays were performed to study the functions of LRP11-AS1. Quantitative PCR and western blot were used to determine the gene expression. Bioinformatics analysis and dual-luciferase reporter assay were conducted to study lncRNA and miRNA interactions. RESULTS: LRP11-AS1 was found to be significantly overexpressed in TNBC cells compared to the non-TNBC cells and normal mammary epithelial cells. Knockdown of LRP11-AS1 could inhibit the growth and metastasis of TNBC cells and regulate cell cycle. Mechanistically, LRP11-AS1 was found to act as a competing endogenous RNA (ceRNA) to sponge miR-149-3p. Silencing of LRP11-AS1 increased the expression of miR-149-3p and overexpression of miR-149-3p suppressed the expression of LRP11-AS1. Inhibition of miR-149-3p could reverse the anticancer effect of LRP11-AS1 deficiency in TNBC cells. Moreover, Neuropilin-2 (NRP2) was found to be the target of miR-149-3p. Rescue experiments revealed that NRP2 overexpression could rescue the anticancer effect of LRP11-AS1 deficiency in TNBC cells. CONCLUSION: LRP11-AS1 overexpressed in TNBC showed the oncogenic effects possibly by sponging miR-149-3p and regulating the miR-149-3p/NRP2 axis, which indicated LRP11-AS1 as a potential diagnostic biomarker and therapeutic target in TNBC.

FBXL19-AS1 aggravates the progression of hepatocellular cancer by downregulating KLF2.

PURPOSE: To uncover the role of FBXL19-AS1 in aggravating the progression of hepatocellular cancer (HCC) by downregulating kruppel-likefactor2 (KLF2). METHODS: FBXL19-AS1 level in HCC tissues and adjacent normal tissues were firstly determined. Its level in HCC with different tumor sizes (≤ 5 cm or > 5 cm) and different tumor stages (stage I-II or III-IV) was examined as well. Subcellular distribution of FBXL19-AS1 was detected. The regulatory effect of FBXL19-AS1 on viability, apoptosis and cell cycle progression of HCC cells was assessed. RNA immunoprecipitation (RIP) assay was conducted to explore the interaction between FBXL19-AS1 with EZH2 and SUZ12. Moreover, chromatin immunoprecipitation (ChIP) assay was carried out to identify the recruitment ability of FBXL19-AS1 on EZH2 and H3K27me3. Finally, the potential role of KLF2 in FBXL19-AS1-mediated HCC proliferation was investigated. RESULTS: FBXL19-AS1 was highly expressed in HCC tissues, especially in those larger than 5 cm in tumor size and worse tumor stage. FBXL19-AS1 was mainly distributed in nucleus and interacted with EZH2 and SUZ12. Knockdown of FBXL19-AS1 suppressed proliferation, cell cycle progression and induced apoptosis of HCC cells. Moreover, silence of FBXL19-AS1 attenuated the recruitment ability of EZH2 on KLF2. Knockdown of KLF2 reversed the regulatory effect of FBXL19-AS1 on proliferative ability of HCC cells. CONCLUSIONS: Long non-coding RNA (lncRNA) FBXL19-AS1 is upregulated in HCC. It accelerates proliferative ability, cell cycle progression and suppresses apoptosis of tumor cells through interacting with KLF2, thus aggravating the progression of HCC.

Effects of dexmedetomidine on glioma cells in the presence or absence of cisplatin.

With the extensive use of dexmedetomidine (Dex) in the surgical resection of tumours for its potent sedative and analgesic properties, its effects on various properties of tumours have received increased attention. The study described herein aimed to investigate the effects of Dex on glioma cells in the presence or absence of cisplatin (DDP). Glioma U251 and U87MG cells were treated with different doses (1-50 nM) of Dex for 12 hours, then recultured in a Dex-free medium. In addition, Dex was added to U251 and U87MG cells 12 hours before or simultaneously with a 12-hour DDP treatment. Treatment with Dex increased the viability of both cell lines; this effect continued for at least 24 hours after Dex was removed. A cell invasion assay indicated that Dex inhibited cell invasion at 50 nM, but not at 10 nM. Western blot analysis showed that Dex increased the expression of phosphorylated extracellular-signal-regulated kinase 1/2, phosphoitide 3-kinase and p-AKT, but decreased ROCK protein levels at a dose of 50 nM. Intracellular Ca 2+ concentration was decreased by Dex in a dose-dependent manner. DDP toxicity was attenuated by 10 nM Dex added either before or with DDP treatment. However, pretreatment with 50 nM Dex instead enhanced the toxicity of DDP. Single-dose treatment with Dex did not significantly change glioma volume in nude mice, but changed the expression of Ki67 and matrix metalloproteinase-3 in the tumour. In conclusion, this study provides evidence of the regulatory effects of Dex on proliferation, invasion and chemosensitivity of glioma cells, and outlines potential mechanisms for these effects.

Effects of ß2/aß2 on oxLDL-induced CD36 activation in THP-1 macrophages.

AIMS: ß2-glycoprotein I/anti-ß2-glycoprotein I antibody complex (ß2/aß2) could promote oxLDL-induced endothelial inflammation through Toll-like receptor 4 (TLR4), therefore accelerates atherosclerosis in patients with anti-phospholipid syndrome (APS). However, effects of ß2/aß2 and TLR4 on oxLDL-induced CD36 activation in macrophages remain to be elucidated and are currently under investigation. MATERIALS AND METHODS: THP-1 macrophages with or without the pre-treatment of TAK-242, a TLR4 inhibitor, were treated with RPMI 1640, oxLDL, oxLDL+ß2/aß2 or oxLDL + LPS.CD36 expression and subsequent intracellular lipid accumulation, cholesterol-transportation-related proteins (ACAT1, ABCG1 and ABCA1) expression, inflammatory cytokines (IL-1ß, TNF-α and IL-6) secretion, focal adhesion kinases (FAK) activation and matrix metalloproteinases (MMP-2 and MMP-9) expression by these THP-1 macrophages were evaluated. Moreover, effects of TLR4 on oxLDL+ß2/aß2-induced peroxisome proliferators-activated receptor-γ (PPAR-γ) expression and CD36 translocation have also been observed. KEY FINDINGS: Compared with oxLDL-treated ones, CD36 expression, intracellular lipid accumulation and FAK activation were inhibited, whereas the levels of inflammatory cytokines and MMPs were upregulated in THP-1 macrophages treated with oxLDL+ß2/aß2 (p < 0.05). Moreover, observed differences between oxLDL-treated and oxLDL+ß2/aß2-treated THP-1 macrophages could be reversed by TAK-242 pre-treatment (p < 0.05). Furthermore, oxLDL+ß2/aß2 promoted PPAR-γ expression and CD36 cytoplasmic translocation in THP-1 macrophages, these effects could also be attenuated by TAK-242 (p < 0.05). SIGNIFICANCE: Through a TLR4 dependent manner, ß2/aß2 inhibited oxLDL-induced CD36 expression, lipid accumulation and FAK activation, while promoted inflammatory cytokines and MMPs expression in THP-1 macrophages, indicating the novel dual roles played by ß2/aß2 in APS-related atherosclerosis.

Identification of hsa_circ_0005654 as a new early biomarker of gastric cancer.

Gastric cancer is one of the most common cancers in the world. However, current medical technologies have not identified a reliable method to cure advanced gastric cancer, and early gastric cancer is difficult to diagnose. Therefore, we focused on circular RNAs (circRNAs) that have been proven to be involved in the carcinogenesis of gastric cancer. We first used quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to evaluate the expression levels of hsa_circ_0005654 in 301 tissues, including 122 healthy gastric mucosa samples, 68 paired tissues from early gastric cancer and adjacent nontumor mucosae obtained by submucosal dissection, and 43 chronic gastritis tissues. Then, we analyzed the relationship between the expression levels of hsa_circ_0005654 and the clinicopathological characteristics of patients with early gastric cancer. We ultimately confirmed the clinical diagnostic value of hsa_circ_0005654 through generating receiver operating characteristic (ROC) curves and comparing the areas under the ROC curves (AUCs).Our data revealed that hsa_circ_0005654 was significantly downregulated in early gastric cancer tissues compared with matched normal mucosae (P< 0.001). Meanwhile, the expression levels of hsa_circ_0005654 in early gastric cancer tissues were also obviously lower than those in chronic gastritis tissues (P< 0.001). The AUCs of early gastric cancer tissues vs. paired normal adjacent mucosae, and that of early gastric cancer vs. healthy controls, were 0.927 and 0.924, respectively. These results clearly demonstrated that hsa_circ_0005654 may serve as a new and promising diagnostic biomarker for screening early gastric cancer. The AUC, sensitivity and specificity of hsa_circ_0005654 are significantly higher than those of present gastric cancer associated-biomarkers.

[oxLDL/ß2GPI/anti-ß2GPI antibody complex inhibits autophagy in RAW264.7 cells through the activation of AKT pathway].

Objective To investigate the effect of oxidative low-density lipoprotein/ß2 glycoprotein I/anti-ß2 glycoprotein I antibody (oxLDL/ß2GPI/anti-ß2GPI antibody) complex on autophagy in mouse macrophages (RAW264.7 cells) and its mechanism. Methods RAW264.7 cells were stimulated with medium, oxLDL, oxLDL/ß2GPI complex, oxLDL/ß2GPI/anti-ß2GPI antibody complex, oxLDL/anti-ß2GPI antibody complex and ß2GPI/anti-ß2GPI antibody complex separately. The protein levels of autophagy-associated proteins including LC3 and P62 were detected by Western blot analysis. The tandem mRFP-GFP-LC3 adernovirus was used to detect the patency of autophagosomes and autophagy flow. The AKT pathway inhibitor LY294002 (50 µmol/L) was used for investigating the role of AKT pathway in the autophagy in RAW264.7 cells treated by oxLDL/ß2GPI/anti-ß2GPI antibody complex. Results oxLDL/ß2GPI/anti-ß2GPI antibody complex reduced the level of LC3-II protein and the number of autophagosomes, increased the level of P62 protein and blocked the autophagy flow. In addition, the autophagy in RAW264.7 cells was partially restored by the pre-treatment of LY294002. Conclusion The oxLDL/ß2GPI/anti-ß2GPI antibody complex can inhibit the autophagy in RAW264.7 cells through activating the AKT pathway.

[OxLDL/ß2GPI/anti-ß2GPI complex promotes calcification and inflammatory cytokine expression in A7r5 cells].

Objective To evaluate the effect of oxidized low-density lipoprotein/ß2-glycoprotein I/anti-ß2 glycoprotein I antibody (oxLDL/ß2GPI/anti-ß2GPI) complex on the calcification and inflammatory cytokine expression in A7r5 rat vascular smooth muscle cells, and to find out the role of Toll-like receptor 4 (TLR4) signal in this process. Methods The A7r5 cells were intervened with oxLDL, oxLDL/ß2GPI complex, oxLDL/anti-ß2GPI complex, ß2GPI/anti-ß2GPI complex, and oxLDL/ß2GPI/anti-ß2GPI complex for different time, with or without TLR4 inhibitor (TAK-242). Alizarin red staining was used to observe the calcification. Real-time quantitative PCR was applied to detect the total mRNA levels of actin-associated protein SM22α (trangelin) and Runt-related transcription factor 2 (RUNX2). The protein levels of SM22α and RUNX2 were measured by Western blotting. Tumor necrosis factor α (TNF-α) was detected by ELISA. Different concentrations of TNF-α were adopted to stimulate A7r5 cells, and the above methods were operated to examine the changes of SM22 and RUNX2. Results When A7r5 cells were incubated by oxLDL/ß2GPI/anti-ß2GPI complex, more calcified nodules were observed, the expression of SM22α was reduced and RUNX2 expression was enhanced at both mRNA and protein levels. And the complex increased the expression of inflammation cytokine TNF-α. TLR4 inhibitor TAK-242 reversed the phenomenon. Different concentrations of TNF-α could reduce mRNA and protein expression of SM22α while raise RUNX2 expression. Conclusion oxLDL/ß2GPI/anti-ß2GPI complex can increase the expression of cytokine TNF-α, and thus quicken calcification procedure in A7r5 cells, along with the change of the traditional contraction phenotype into the osteogenic phenotype. TLR4 receptor participates in this process.

[The ß2GPI/aß2GPI inhibits phagocytosis of oxidized low-density lipoprotein in THP-1 macrophages via activating TLR4].

Objective To investigate the effects of ß2 glycoprotein I/anti-ß2 glycoprotein I antibody complex (ß2GPI/aß2GPI) on lipid phagocytosis and class B scavenger receptor CD36 expression of macrophages, and the role of Toll-like receptor 4 (TLR4) during the process. Methods THP-1 macrophages were induced from THP-1 cells treated by 100 ng/mL phorbol ester (PMA), and then identified by morphological observation and DiI-oxLDL uptake assay. THP-1 macrophages were treated with RPMI1640 medium, ß2GPI, aß2GPI or ß2GPI/aß2GPI. The protein and mRNA expression of TLR4 were detected by Western blot analysis and real-time fluorescent quantitative PCR (qRT-PCR), respectively. After that, THP-1 macrophages were treated with RPMI1640 medium, oxidized low-density lipoprotein (oxLDL), oxLDL combined with ß2GPI/aß2GPI or oxLDL combined with LPS. Intracellular lipid deposition was observed by oil red O staining; the mRNA and protein expression of CD36 were detected by qRT-PCR, immunofluorescence and Western blot analysis. To unveil the role of TLR4 in this process, THP-1 macrophages were pre-treated with or without TLR4 inhibitor TAK-242 (1 µg/mL). Results After PMA treatment, THP-1 cells showed macrophage-like morphology and were able to engulf DiI-oxLDL. Compared with RPMI1640 medium, ß2GPI/aß2GPI treatment significantly increased TLR4 expression in THP-1 macrophages. Compared with oxLDL alone, oxLDL combined with ß2GPI/aß2GPI inhibited lipid deposition and CD36 expression in THP-1 macrophages, which could be partly reversed by TLR4 blockage. Conclusion The ß2GPI/aß2GPI can inhibit the phagocytosis of oxLDL and CD36 expression in macrophages, which is linked to the function of TLR4.

Hydrogen sulfide attenuates doxorubicin-induced cardiotoxicity by inhibiting the expression of peroxiredoxin III in H9c2 cells.

Doxorubicin (DOX) is a widely used chemotherapeutic agent, which can give rise to severe cardiotoxicity, limiting its clinical use. Preliminary evidence suggests that hydrogen sulfide (H2S) may exert protective effects on DOX­induced cardiotoxicity. Therefore, the aim of the present study was to investigate whether peroxiredoxin III is involved in the cardioprotection of H2S against DOX­induced cardiotoxicity. The results demonstrated that DOX not only markedly induced injuries, including cytotoxicity and apoptosis, it also increased the expression levels of peroxiredoxin III. Notably, pretreatment with sodium hydrosulfide significantly attenuated the DOX­induced decrease in cell viability and increase in apoptosis, and also reversed the increased expression levels of peroxiredoxin III in H9c2 cardiomyocytes. In addition, pretreatment of the H9c2 cells with N­acetyl­L­cysteine, a scavenger of reactive oxygen species, prior to exposure to DOX markedly decreased the expression levels of peroxiredoxin III. In conclusion, the results of the present study suggested that exogenous H2S attenuates DOX­induced cardiotoxicity by inhibiting the expression of peroxiredoxin III in H9c2 cells. In the present study, the apoptosis of H9c2 cardiomyocytes was assessed using an methyl thiazolyl tetrazolium assay and Hoechst staining. The levels of Prx III and cystathionine-γ-lyase were examined by western blotting.

Resveratrol induces apoptosis through modulation of the Akt/FoxO3a/Bim pathway in HepG2 cells.

Resveratrol is a polyphenolic compound found in wine, which is mainly produced by the grapevine and exerts chemopreventive effects against hepatocellular carcinoma. However, the underlying molecular mechanisms have remained to be fully elucidated. The present study assessed whether resveratrol-induced apoptosis was mediated via the activation of the forkhead box O3a (FoxO3a) transcription factor. It was demonstrated that resveratrol treatment induced apoptosis in HepG2 cells, and that this pro-apoptotic effect was accompanied with increases in the expression of apoptotic protein Bim. Following resveratrol treatment, Akt-mediated phosphorylation of FoxO3a was observed to be diminished in HepG2 cells. Furthermore, resveratrol enhanced the nuclear levels of FoxO3a and mediated neuronal death via Bim. The present study demonstrated that resveratrol induced apoptosis in HepG2 cells through activation of the transcription factor FoxO3a and increasing the expression of Bim protein.

Resveratrol protects cardiomyocytes from doxorubicin-induced apoptosis through the AMPK/P53 pathway.

Doxorubicin (DOX) is an efficient drug used in cancer therapy; however, it has severe cardiotoxic side effects. The aim of the present study was to investigate the effects of resveratrol on the adenosine monophosphate-activated protein kinase (AMPK)/P53 pathway in mediating DOX-induced cytotoxicity. H9c2 cells were exposed to 5 µM DOX for 24 h to establish a model of DOX-induced cardiotoxicity. DOX administration amplified P53 and B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) expression and decreased Bcl-2 expression in H9c2 cells. Resveratrol increased the cell viability and decreased the apoptotic rate. In addition, resveratrol markedly increased the phosphorylation of AMPK. Of note, resveratrol protected against DOX-induced increases of P53 and Bax and also prevented the downregulation of Bcl-2 in H9c2 cells. Furthermore, AMPK inhibitor Compound C abolished the protective effects of resveratrol. The results of the present study therefore indicated that resveratrol protected H9c2 cells from DOX-induced apoptosis via the AMPK/P53 pathway.

Upregulation of peroxiredoxin III in doxorubicin-induced cytotoxicity and the FoxO3a-dependent expression in H9c2 cardiac cells.

Doxorubicin (DOX) is an efficient drug used in cancer therapy; however, it produces reactive oxygen species (ROS) that induce severe cytotoxicity, limiting its clinical application. The aim of the present study was to investigate the role of peroxiredoxin III (Prx III) in DOX-induced H9c2 cell injuries. Following DOX treatment, the expression of phosphorylated-FoxO3a (p-FoxO3a) was decreased and Prx III expression was increased in H9c2 cells. In order to detect whether oxidative stress was involved in the induction of Prx III expression by FoxO3a, exogenous H2O2 was used to induce oxidative stress in the H9c2 cells. Apoptosis of H9c2 cardiomyocytes was assessed using methyl thiazolyl tetrazolium assay and Hoechst staining. The levels of Prx III and p-FoxO3a were evaluated using western blot analysis. As expected, H2O2 was found to mimic the effect of DOX, decreasing the expression of p-FoxO3a and increasing the expression of Prx III. In addition, the study evaluated whether the transcription factor FoxO3a was essential for the expression of Prx III. Pretreatment of H9c2 cells with N-acetyl-L-cysteine (NAC), a scavenger of ROS, prior to exposure to DOX dramatically increased the phosphorylation of FoxO3a and led to a marked reduction in Prx III expression in the H9c2 cells. In conclusion, the results of the current study suggest that FoxO3a mediates the expression of Prx III in DOX-induced injuries.

Induction of microRNA-146a is involved in curcumin-mediated enhancement of temozolomide cytotoxicity against human glioblastoma.

MicroRNA (miR)-146a is a negative regulator of nuclear factor-κB (NF-κB) signaling that affects tumor growth and survival. The present study was undertaken to determine whether the cytotoxicity of curcumin (diferuloylmethane), a natural polyphenolic compound isolated from turmeric (Curcuma longa Linn), in glioblastoma cells is mediated through upregulation of miR­146a. Human U­87 MG glioblastoma cells were treated with curcumin and temozolomide (TMZ) alone or in combination, and cell proliferation and apoptosis were assessed. The involvement of miR­146a and NF­κB signaling in curcumin­mediated chemosensitization was explored. Curcumin exposure led to upregulation of miR­146a in U­87 MG cells. Combined curcumin and TMZ treatment significantly (P<0.05) inhibited U­87 MG cell proliferation and induced apoptotic death, compared with each alone. Notably, curcumin­mediated enhancement of TMZ­induced apoptosis was blocked by depletion of miR­146a. By contrast, miR­146a overexpression enhanced apoptosis and suppressed NF­κB activation in TMZ­treated cells. Additionally, pharmacological inhibition of NF­κB signaling significantly increased TMZ­induced apoptosis. To the best of our knowledge, the present study provides the first evidence that upregulation of miR­146a and inactivation of NF­κB signaling mediates the sensitization of human glioblastoma cells to TMZ-induced apoptosis by curcumin.

Hydrogen sulfide attenuates doxorubicin­induced cardiotoxicity by inhibiting calreticulin expression in H9c2 cells.

Doxorubicin (DOX) is a potent and currently available antitumor therapeutic agent; however, its clinical application is limited by the occurrence of cardiotoxicity. Preliminary evidence indicates that hydrogen sulfide (H2S) may exert protective effects against DOX cardiotoxicity. Therefore, the aim of the present study was to investigate whether calreticulin (CRT) is involved in the cardioprotection of H2S against DOX­induced cardiotoxicity. DOX was observed to markedly induce injuries, including cytotoxicity and apoptosis, and also enhance the expression level of CRT. Notably, pretreatment of H9c2 cells with sodium hydrosulfide (a donor of H2S) significantly attenuated the decreased cell viability, the increased apoptosis rate and the increased expression level of CRT in H9c2 cells. In addition, pretreatment of H9c2 cells with N­acetyl­L­cysteine, a scavenger of reactive oxygen species (ROS) prior to exposure to DOX, markedly decreased the expression of CRT. These results indicate that exogenous H2S attenuates DOX­induced cardiotoxicity by inhibiting CRT expression in H9c2 cardiac cells.

[Relationship between serum level of uric acid and benign paroxysmal positional vertigo].

OBJECTIVE: To confirm the possible relationships between serum level of uric acid (UA) and benign paroxysmal positional vertigo (BPPV). METHODS: A total of 87 patients with BPPV and 36 age- and gender-matched control subjects were recruited from our hospital between July 1, 2013 and July 1, 2014. All patients underwent a complete audio-vestibular test battery, such as Dix-Hallpike maneuver for posterior semicircular canal and supine roll test for horizontal semicircular canal. All risk factors such as the histories of heart and cerebral vascular diseases, and routine hematological and biochemical analyses were analyzed between two groups. RESULTS: No significant inter-group differences existed in age, gender, histories of hypertension, diabetes mellitus, hyperlipidemia, coronary heart disease, smoking or drinking (P > 0.05). No significant differences existed between systolic blood pressure, diastolic blood pressure, ejection fraction, whole blood count, lipid profile, homocysteine, prealbumin and blood urea nitrogen in patients with BPPV compared with controls (P >0. 05). However, the values of UA (267 ± 86 vs 325 ± 75) µmol/L, hemoglobin ale (5.6 ± 1. 4 vs 6.5 ± 1. 0)%, albumin (36 ± 4 vs 40 ± 4) g/L and creatinine (72 ± 20 vs 81 ± 22) µmol/L were much lower in patients with BPPV versus controls (P < 0. 05). According to multiple Logistic regression model, the lower levels of hemoglobin ale and albumin were independently associated with BPPV (P <0. 05) with the odds ratio of 1. 473 (95% CI 1. 066 - 2. 037) and 1. 162 (95% CI 1. 025 - 1. 318), respectively. However, the level of UA was not independently correlated with the occurrence of BPPV [OR = 1. 005 (95% CI 1. 000 - 1. 011), P =0. 063]. CONCLUSION: The lower levels of hemoglobin alc and albumin are independently associated with BPPV. Although the value of UA is lower in patients with BPPV versus controls, it is not an independent risk factor for BPPV. Due to limited patient data, further studies are needed to clarify the association in a larger sample size of different ethnic groups or longer follow ups.

Resveratrol protects PC12 cells from high glucose-induced neurotoxicity via PI3K/Akt/FoxO3a pathway.

Diabetes is known to be associated with neurodegenerative diseases. Resveratrol, a plant-derived polyphenolic compound found in red wine, possesses antioxidant properties. In this study, we aimed to investigate the effects of resveratrol on the phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt)/FoxO3a pathway in mediating high glucose (HG)-induced injuries in neuronal PC12 cells. PC12 cells were exposed to HG to establish a model of HG neurotoxicity. Results showed that pre-treating PC12 cells with resveratrol before exposure to HG led to increased cell viability, decreased apoptotic cells, and reactive oxygen species generation. Western blot analysis showed that HG decreased the phosphorylation of Akt and FoxO3a and led to the nuclear localization of FoxO3a. These effects were significantly alleviated by resveratrol co-treatment. Furthermore, the protective effects of resveratrol were abolished by PI3K/Akt inhibitor LY294002. All these results demonstrate that resveratrol protected the PC12 cells from HG-induced oxidative stress and apoptosis via the activation of PI3K/Akt/FoxO3a signaling pathway.

MiR-136 modulates glioma cell sensitivity to temozolomide by targeting astrocyte elevated gene-1.

BACKGROUND: Recent studies have linked chemotherapy resistance to the altered expression of microRNAs (miRNAs). Thus, miRNA-based approaches to modulating sensitivity to temozolomide (TMZ) may overcome chemoresistance. The aim of the present study was to investigate whether miR-136 could modulates glioma cell sensitivity to TMZ. METHODS: The proliferation of glioma U251 cell line was evaluated by MTT assay. The expression of astrocyte elevated gene-1 (AEG-1)was detected by real­time polymerase chain reaction (RT-PCR)and Western blot. The luciferase reporter gene was used to test whether AEG-1 was the target of the miR-136. RESULTS: The MTT assay showed that U251 cells with miR-136 overexpression were significantly more sensitive to the therapy of TMZ than control cells. Luciferase assays revealed that miR-136 directly targeted the 3'UTR of AEG-1. qRT-PCR and western blotting analysis found that AEG-1 expression at the mRNA and protein levels decreased in the miR-136 mimic-treatment group relative to control group. Downregulation of AEG-1 expression by siRNAs, U251 cells became more sensitive to the therapy of TMZ. In addition, the enhanced growth-inhibitory effect by the miR-136 mimics transfection was enhanced after the addition of AEG-1 siRNA. CONCLUSIONS: The present study provides the first evidence that miR-136 plays a key role in TMZ resistance by targeting the AEG-1 protein in glioma cell line, suggesting that miR-136 can be used to predict a patient's response to TMZ therapy as well as serve as a novel potential maker for glioma therapy. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_173.