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The present study was to investigate the role of TRPC6 in pulmonary artery smooth muscle cells (PASMCs) proliferation and apoptosis under hypoxia and hypercapnia. PASMCs were isolated from chloral hydrate-anesthetized male Sprague-Dawley (SD) rats. Cellular purity was assessed by immunofluorescence staining for smooth muscle α-actin under fluorescence microscopy. Passage 4-6 PASMCs were starved for 24 h in serum-free DMEM and divided into 5 groups randomly: normoxia, hypoxia and hypercapnia, DMSO, TRPC6 inhibitor SKF-96365 and TRPC6 activator OAG groups. The normoxic group was incubated under normoxia (5% CO 2 , 21% O 2 , 37 °C) for 24 h, and the others were incubated with corresponding drugs under hypoxic and hypercapnic (6% CO 2 , 5% O 2 , 37 °C) atmosphere for 24 h. TRPC6 mRNA was detected by reverse transcription-PCR. TRPC6 protein was detected by Western blotting. The proliferation of PASMCs was performed by CCK-8 kit. Apoptosis of the PASMCs was detected using TUNEL assay. The [Ca 2+ ] i in the PASMCs was measured using Fura 2-AM fluorescence. The results showed that the expressions of TRPC6 mRNA and protein, and [Ca 2+ ] i were upregulated under hypoxic and hypercapnic conditions. Hypoxia and hypercapnia promoted cellular proliferation and inhibited apoptosis in the PASMCs. OAG enhanced the above-mentioned effects of hypoxia and hypercapnia, whereas SKF-96365 reversed these effects. These results suggest that TRPC6 may play a role in PASMCs proliferation and apoptosis under hypoxia and hypercapnia by regulating [Ca 2+ ] i .

Objective: To investigate the effects of arsenic trioxide (As 2 O 3 ) on K562 cell proliferation by regulating cell cycle protein D1 and cyclin-dependent kinase inhibitor p27kip1., Methods: MTT was used to detect the effect of As 2 O 3 on K562 cell proliferation, so as to screen out the appropriate drug concentration. Furthermore, the K562 cell apoptosis was observed by microscopy. The expression of CyclinD1 and p27kip1 in K562 cells treated with As 2 O 3 was analyzed by reverse transcription-polymerase chain reaction(RT-PCR), immunohistochemistry and Western blot., Results: As 2 O 3 could inhibit the proliferation of K562 cells in a dose- and time- dependent manner (r= 0.967). And the apoptosis cell number in As 2 O 3 group was significantly higher than that in the control group(P<0.05). As 2 O 3 could markedly inhibit the expression of CyclinD1 in K562 cells(P<0.05), but the expression of P27kip1 was not significantly changed after As 2 O 3 treatment., Conclusions: As 2 O 3 can induce K562 cell apoptosis and inhibit K562 cell proliferation by regulating the expression of CyclinD1.

The transcriptional regulator Yin Yang-1 (YY1) is a tumor suppressor known to be overexpressed in pancreatic cancer. We found that overexpression of YY1 promoted apoptosis and increased the expression and mitochondrial localization of the pro-apoptotic Bax protein in pancreatic cancer cell lines. Luciferase reporter, electrophoretic mobility shift (EMSA), and chromatin immunoprecipitation (ChIP) assays revealed binding of YY1 to the BAX promoter. Moreover, YY1 promoted pancreatic cancer cell apoptosis through Bax transcriptional activation and subsequent translocation of Bax to the mitochondrial membrane, leading to cytochrome c release, and caspase activation.YY1 and BAX are co-expressed in pancreatic cancer tissues and higher BAX expression predicts better outcomes for patients. The ability of YY1 to promote apoptosis in pancreatic cancer cells suggests it may represent a valuable diagnostic and therapeutic target., Competing Interests: The authors disclose no potential conflicts of interest.

Tumor-associated MUC4 mucin has considerable potential as an immunotherapy target for pancreatic cancer. In previous studies, we developed dendritic cell (DC) vaccines which elicited MUC4 antigen-specific cytotoxic T lymphocyte (MS-CTL) response against tumor cells in vitro. Due to the observation that MS-CTL apoptotic rate increased significantly when co-cultured with MUC4+ tumor cells compared with T2 cells, we investigated whether high expression levels of MUC4 in pancreatic cancer cells would have an effect on the significant increase of apoptosis rate of MS-CTLs. First, the adverse influence of regulatory T cells (Tregs) was eliminated by CD8+ T lymphocyte sorting before the induction of MS-CTLs. Then, we constructed clonal MUC4-knockdown HPAC pancreatic cancer sublines with different MUC4 expression for co-incubation system. By utilizing appropriate control to rule out the possible apoptosis-induced pathway of intrinsic activated cell-autonomous death (ACAD) and analogous antigen-dependent apoptosis of CTL (ADAC) in our study system, further analysis of the effect of MUC4 membrane-expression, supernatants and blockade of CTL surface Fas receptor on MS-CTL apoptosis was carried out. The results demonstrated that the level of MUC4 membrane expression strongly positively correlated with MS-CTL apoptosis and the influence of supernatants and Fas-blockade did not significantly correlate with MS-CTL apoptosis. This evidence suggested that there may be a novel counterattack pathway of pancreatic cancer cells, which is a MUC4-mediated, cell contact-dependent and Fas-independent process, to induce CTL apoptosis. Therefore, further exploration and understanding of the potential counterattack mechanisms is beneficial to enhance the efficacy of MUC4 specific tumor vaccines.

The ability for early evaluation of therapeutic effects is a significant challenge in leukemia research. To address this challenge, we developed a novel electrochemical platform for ultrasensitive and selective detection of apoptotic cells in response to therapy. In order to construct the platform, a novel three-dimensional (3-D) architecture was initially fabricated after combining nitrogen-doped carbon nanotubes and gold nanoparticles via a layer-by-layer method. The formed architecture provided an effective matrix for annexin V with high stability and bioactivity to enhance sensitivity. On the basis of the specific recognition between annexin V and phosphatidylserine on the apoptotic cell membrane, the annexin V/3-D architecture interface showed a predominant capability for apoptotic cell capture. Moreover, a lectin-based nanoprobe was designed by noncovalent assembly of concanavalin A on CdTe quantum dots (QDs)-labeled silica nanospheres with poly(allylamine hydrochloride) as a linker. This nanoprobe incorporated both the specific carbohydrate recognition and the multilabeled QDs-based signal amplification. By coupling with the QDs-based nanoprobe and electrochemical stripping analysis, the proposed sandwich-type cytosensor showed an excellent analytical performance for the ultrasensitive detection of apoptotic cells (as low as 48 cells), revealing great potential toward the early evaluation of therapeutic effects., (© 2011 American Chemical Society)

The activation of nuclear factor-κB (NF-κB) has been implicated in the development and progression of endometriosis. The aim of this study is to investigate the potential application of pyrrolidine dithiocarbamate (PDTC), a potent NF-κB inhibitor, in the treatment of endometriosis. NF-κB-DNA-binding activity, IκB phosphorylation and expression of nuclear p65 protein in endometriotic ectopic stromal cells (EcSCs), endometriotic eutopic stromal cells (EuSCs) and normal endometrial stromal cells (NESCs) were detected by electrophoretic mobility shift assay and western blot analysis. Adhesion, migration, invasion and apoptosis of EcSCs were observed by means of adhesion, migration, invasion and terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling assay, respectively. Gene and protein expressions of CD44s, matrix metalloproteinase (MMP)-2, MMP-9 and survivin in EcSCs were measured by RT-PCR and western blot analysis. The results showed that PDTC in the absence or presence of interleukin (IL)-1β showed stronger inhibitory effects on NF-κB-DNA-binding activity, IκB phosphorylation and expression of nuclear p65 protein in EcSCs than those in EuSCs or NESCs. PDTC enhanced apoptosis, and suppressed IL-1β-induced cellular adhesion, migration and invasion of EcSCs. Pretreatment of EcSCs with PDTC attenuated IL-1β-induced expressions of CD44s, MMP-2, MMP-9 and survivin at gene and protein levels. All these findings suggest that PDTC induces apoptosis and down-regulates adhesion, migration and invasion of EcSCs through the suppression of various molecules. Therefore, PDTC could be used as a therapeutic agent for the treatment of endometriosis.

Nasopharyngeal carcinoma is a malignant tumor with high incidence in Asia. This study investigated the anti-tumor capacities of lupeol in nasopharyngeal carcinoma. CCK-8 assay was employed to select the suitable concentration and intervention time of lupeol in 5–8 F and CNE1 cells. The anti-cancer impacts of lupeol were evaluated by flow cytometry, ROS generation, western blotting, ELISA, iron assay, lipid peroxidation, mitochondrial membrane potential (MMP), TUNEL, and immunohistochemistry assays. Additionally, levels of AMPK/NF-κB pathway-related proteins were tested by western blotting. Cell viability was notably decreased after administration of lupeol ≧ 20 μM. 20 μM and 40 μM lupeol induced cell apoptosis, enhanced oxidative stress and restrained immune response in nasopharyngeal carcinoma cells to some extent, as evidenced by the elevation of apoptotic rate, Bax and cleaved caspase-3 expression, ROS production and malondialdehyde level, and reduction of levels of Bcl-2, MMP, superoxide dismutase, TNF-α, IL-6 and IL-1β. Also, lupeol promoted the iron secretion and lipid peroxidation, the effects of which were reversed by ferroptosis inhibitor (Fer-1). The inhibitory impacts of lupeol at the doses of 20 μM and 40 μM on glutathione and GPX4 levels were observed. Importantly, lupeol significantly elevated AMPKα phosphorylation, and reduced the levels of p-IκBα and nuclear NF-κB p65. Rescue assay stated that siAMPK could neutralize the above impacts of lupeol. Moreover, lupeol suppressed tumorigenesis of xenografts in nude mice. Lupeol exerted the anti-cancer impacts by inducing oxidative stress, ferroptosis and apoptosis, and suppressing inflammation via the AMPK/NF-κB pathway in nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the role of Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway in protection by peritoneal resuscitation (PR) using pyruvate-peritoneal dialysis solution (PY-PDS) against intestinal injury from hemorrhagic shock (HS) in rats. Sixty-four rats were assigned to eight groups: group SHAM; group intravenous resuscitation (VR); groups NS, LA, and PY in which the rats were subjected to HS and PR with normal saline (NS), lactate-peritoneal dialysis solution (LA-PDS), and PY-PDS, respectively, combined with VR; and groups DMSO, RPM, and AG490 in which the rats were subjected to HS and VR with pretreatment of dimethyl sulfoxide (DMSO), rapamycin (RPM), and tyrphostin B42 (AG490). At 2 h after HS and resuscitation, the levels of diamine oxidase, 15-F 2t -isoprostane, thromboxane B 2 , and endothelin-1, in the blood and the intestinal mucosal apoptotic index and caspase-3 were lower in groups PY, RPM, and AG490 than in groups VR, NS, LA, and DMSO. Group PY showed lower levels of malondialdehyde and myeloperoxidase and a higher level of superoxide dismutase than groups VR, NS, and LA. Phosphorylated JAK2 and phosphorylated STAT3 levels were lower in groups PY, RPM, AG490, and LA than in groups VR, NS, and DMSO. The protection mechanism of PR with PY-PDS combined with VR was related to the inhibition of the JAK/STAT signaling pathway during HS and resuscitation. The process might include suppression of oxidative stress, reduction of neutrophil infiltration, regulation of microcirculation, and inhibition of apoptosis. [ABSTRACT FROM AUTHOR]

The transcription regulator Yin Yang-1 (YY1) serves as a tumor suppressor in pancreatic ductal adenocarcinoma (PDAC). However, the function of YY1 in proliferation of PDAC cells remains to be clarified. In this study, we found that overexpression of YY1 suppressed proliferation and decreased the expression of long non-coding RNA (lncRNA) SOX2OT and its potential target gene SOX2 in PDAC cells. Luciferase reporter, electrophoretic mobility shift (EMSA), and chromatin immunoprecipitation (ChIP) assays revealed binding of YY1 to the SOX2OT promoter. Moreover, YY1 suppressed PDAC cell proliferation through SOX2OT transcriptional inhibition and subsequent decreased SOX2 expression. In addition, YY1 expression was statistically negatively correlated with SOX2OT and SOX2 expression in PDAC tissues and lower level expression of SOX2OT predicted better outcome in PDAC patients. These results confirmed the anti-proliferation effect of YY1 on PDAC cells, which was associated with SOX2 down-regulation in a SOX2OT-dependent mechanism. Although other undiscovered mechanisms may be involved in the YY1-mediated tumor suppression role, the present study suggests that SOX2OT may act as a tumor promotor in PDAC and may represent a valuable diagnostic and therapeutic target. [ABSTRACT FROM AUTHOR]

Aims To evaluate the therapeutic effects of n-butylidenephthalide ( BP) in SOD1G93A mouse model of amyotrophic lateral sclerosis and explore the possible mechanisms. Methods The SOD1G93A mice were treated by oral administration of BP (q.d., 400 mg/kg d) starting from 60 days of age and continuing until death. The rotarod test was performed to assess the disease onset. The expression levels of apoptosis-related proteins, inflammatory molecules, and autophagy-associated proteins were determined. The number of apoptotic motor neurons and the extent of microglial and astroglial activation were also assessed in the lumbar spinal cords of BP-treated mice. Grip strength test, hematoxylin-eosin staining, nicotinamide adenine dinucleotide hydrogen staining, and malondialdehyde assay were conducted to evaluate the muscle function and pathology. Results Although BP treatment did not delay the disease onset, it prolonged the life span and thereafter extended the disease duration in SOD1G93A mouse model of ALS. BP treatment also reduced the motor neuron loss through inhibiting apoptosis. We further demonstrated that the neuroprotective effects of BP might be resulted from the inhibition of inflammatory, oxidative stress, and autophagy. Conclusion Our study suggests that BP may be a promising candidate for the treatment of ALS. [ABSTRACT FROM AUTHOR]

The α7 nicotinic acetylcholine receptor (α7nAChR) belongs to the superfamily of cys loop cationic ligand-gated channels, which consists of homogeneous α7 subunits. Although our lab found that activation of α7nAChR could alleviate ischemic stroke, the mechanism is still unknown. Herein, we explored whether autophagy is involved in the neuroprotective effect mediated by α7nAChR in ischemic stroke. Transient middle cerebral artery occlusion (tMCAO) and oxygen and glucose deprivation (OGD/R) exposure were applied to in vivo and in vitro models of ischemic stroke, respectively. Neurological deficit score and infarct volume were used to evaluate outcomes of tMCAO in the in vivo study. Autophagy-related proteins were detected by Western blot, and autophagy flux was detected by using tandem fluorescent mRFP-GFP-LC3 lentivirus. At 24 h after tMCAO, α7nAChR knockout mice showed worse neurological function and larger infarct volume than wild-type mice. PNU282987, an α7nAChR agonist, protected against OGD/R-induced neuronal injury, enhanced autophagy, and promoted autophagy flux. However, the beneficial effects of PNU282987 were eliminated by 3-methyladenine (3-MA), an autophagy inhibitor. Moreover, we found that PNU282987 treatment could activate the AMPK-mTOR-p70S6K signaling pathway in the in vitro study, while the effect was attenuated by compound C, an AMPK inhibitor. Our results demonstrated that the beneficial effect on neuronal survival via activation of α7nAChR was associated with enhanced autophagy, and the AMPK-mTOR-p70S6K signaling pathway was involved in α7nAChR activation–mediated neuroprotection. [ABSTRACT FROM AUTHOR]

Ischemic stroke is one of the leading causes of mortality, but therapies are limited. Dengzhan Shengmai capsule (DZSM) was included by the Chinese Pharmacopoeia 2020 and has been broadly used for the treatment of ischemic stroke. However, the mechanism of DZSM against ischemic stroke is unclear. This study used RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) to investigate the mechanism of action of DZSM against ischemic stroke. The rats were randomly divided into six groups: the Sham, I/R (water), I/R + DZSM-L (0.1134g/kg), I/R + DZSM-H (0.4536g/kg), I/R + NMDP (20mg/kg), and I/R + Ginaton (20mg/kg). The rats were administrated drugs for 5 days then followed by the ischemic brain injury caused by middle cerebral artery occlusion (MCAO). The neuroprotective effect was assessed by infraction rate, neurological deficit scores, regional cerebral blood flow (rCBF), hematoxylin and eosin (H&E) staining, and Nissl staining. Based on RNA-seq and scRNA-seq, the vital biological processes and core targets of DZSM against cerebral ischemia were revealed. Enzyme-linked immunosorbent assay (ELISA) and immunofluorescence (IF) staining were used to investigate the vital biological processes and core targets of DZSM against ischemic stroke. Administration of DZSM significantly reduced the infarction rate and Zea Longa score, Garcia JH score, and ameliorated the reduction in rCBF. And alleviated the neuronal damage, such as increased neuronal density level and Nissl bodies density level. RNA-seq analysis revealed that DZSM played important roles in inflammation and apoptosis. ELISA and IF straining validation confirmed that DZSM significantly decreased the expression of IL-6, IL-1β, TNF-α, ICAM-1, IBA-1, MMP9, and Cleaved caspase-3 in MCAO rats. ScRNA-seq analysis identified 8 core targets in neurons including HSPB1, SPP1, MT2A, GFAP, IFITM3, VIM, CRIP1, and GPD1, and VIM and IFITM3 was verified to be decreased by DZSM in neurons. Our study illustrates the neuroprotective effect of DZSM against ischemia stroke, and VIM and IFITM3 were identified as vital targets in neurons of DZSM in protecting against MCAO-induced I/R injury. [Display omitted] [ABSTRACT FROM AUTHOR]