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Background: Colorectal cancer (CRC) is one of the most prevalent cancer types worldwide. Despite the advancements in current diagnosis and treatment strategies of CRC, the incidence and mortality rates of CRC have been rising. To explore novel mechanism of CRC, this study focused on the expression pattern and functional mechanism of murine retrovirus integration site 1 (MRVI1) in CRC. Methods: Tumor tissues and adjacent normal tissues were collected from CRC patients, and the expression levels of MRVI1 were determined by RT-PCR and Western blot. MRVI1 knockdown was achieved by shRNA in HCT116 and HT29 cells, followed by CCK-8 assay to detect the cell proliferation, and caspase-3 activity assay combined with nucleosome ELISA assay to detect cell apoptosis. Transwell assay was used to detect cell invasion and luciferase reporter assay was used to validate the activation of the MRVI1 promoter by p53. Results: MRVI1 was downregulated in CRC tissues and several CRC cell lines. Knockdown of MRVI1 enhanced the proliferation and apoptosis, while promoted invasion and stemness of CRC cells. Mechanism study revealed that MRVI1 was transcriptionally activated by p53 at its upstream. In addition, p53-induced inhibition of CRC prognosis depended on MRVI1. Conclusion: MRVI1 inhibited the prognosis of CRC via a mechanism involving p53 activation. MRVI1 could serve as a potential target for clinical diagnosis and treatment of CRC. [ABSTRACT FROM AUTHOR]

Background Hypoxia-ischemia is an important cause of brain injury and neurological morbidity in the newborn infants. The activity of glycogen synthase kinase-3β (GSK-3β) is up-regulated following neonatal stroke. Tideglusib is a GSK-3β inhibitor which has neuroprotective effects against neurodegenerative diseases in clinical trials. However, the effect of tideglusib on hypoxic-ischemic (HI) brain injury in neonates is still unknown. Methods Postnatal day 7 (P7) mouse pups subjected to unilateral common carotid artery ligation followed by 1 h of hypoxia or sham surgery was performed. HI animals were administered tideglusib (5 mg/kg) or vehicle intraperitoneally 20 min prior to the onset of ischemia. The brain infarct volume and whole brain images, were used in conjunction with Nissl staining to evaluate the protective effects of tideglusib. Protein levels of glial fibrillary acidic protein (GFAP), Notch1, cleaved caspase-3/9, phosphorylated signal transducer and activator of transcription 3 (STAT3), GSK-3β and protein kinase B (Akt) were detected to identify potentially involved molecules. Results Tideglusib significantly reduced cerebral infarct volume at both 24 h and 7 days after HI injury. Tideglusib also increased phosphorylated GSK-3β(Ser9) and Akt(Ser473), and reduced the expression of GFAP and p-STAT3(Tyr705). In addition, pretreatment with tideglusib also enhanced the protein level of Notch1. Moreover, tideglusib reduced the cleavage of pro-apoptotic signal caspase proteins, including caspase 3 and caspase 9 following HI. Conclusion These results indicate that tideglusib shows neuroprotection against hypoxic-ischemic brain injury in neonatal mice. General significance Tideglusib is a potential compound for the prevention or treatment of hypoxic-ischemic brain injury in neonates. [ABSTRACT FROM AUTHOR]

Rationale: Lithium is currently used in the treatment of mental illness. We have previously reported that lithium stimulated the protein kinase B/Forkhead box O1 (Akt/FoxO1) pathway in rats. However, little information is available regarding its neuroprotective role of this pathway and underlying mechanisms. Objectives: PC12 cells treated with serum deprivation were used as a toxicity model to study the protective effect of lithium and its underlying mechanisms. Methods: Cell viability was determined by methyl thiazolyl tetrazolium assay and Hoechst staining. FoxO1 subcellular location and its overexpression were used to study the underlying mechanisms. Various pathway inhibitors were used to investigate the possible pathways, while the phosphorylation of Akt and FoxO1 was analyzed by Western blot. Results: Lithium pretreatment dose-dependently reduced PC12 cell apoptosis induced by serum starvation. The protective effect of lithium was abolished by LY294002, a PI3K-specific inhibitor, and Akt inhibitor Akt inhibitor VIII, whereas mitogen-activated protein kinase kinase (MEK kinase) inhibitor U0126 had no effect. Lithium induced the phosphorylation of Akt and FoxO1 in a time- and concentration-dependent manner. Lithium-induced phosphorylation of Akt and FoxO1 is mediated by the PI3K/Akt pathway. Serum deprivation caused nuclear translocation of FoxO1 while application of lithium reversed the effect of serum deprivation. Moreover, overexpression of FoxO1 enhanced cell apoptosis induced by serum withdrawal. Finally, lithium was found to reduce the exogenous and endogenous FoxO1 protein levels in PC12 cells in a concentration-dependent fashion. Conclusions: The protective effect of lithium against serum starvation cell death is mediated by the PI3K/Akt/FoxO1 pathway. [ABSTRACT FROM AUTHOR]

The accumulation and deposition of β-amyloid peptide (Aβ) in senile plaques and cerebral vasculature is believed to facilitate the progressive neurodegeneration that occurs in the Alzheimer's disease (AD). The present study sought to elucidate possible effects of baicalin, a natural phytochemical, on Aβ toxicity in a rat model of AD. By morris water maze test, Aβ injection was found to cause learning and memory deficit in rat, which was effectively improved by baicalin treatment. Besides, histological examination showed that baicalin could attenuate the hippocampus injury caused by Aβ. The neurotoxicity mechanism of Aβ is associated with oxidative stress and apoptosis, as revealed by increased malonaldehyde generation and TUNEL-positive cells. Baicalin treatment was able to increase antioxidant capabilities by recovering activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and up-regulating their gene expression. Moreover, baicalin effectively prevented Aβ-induced mitochondrial membrane potential decrease, Bax/Bcl-2 ratio increase, cytochrome c release, and caspase-9/-3 activation. In addition, we found that the anti-oxidative effect of baicalin was associated with Nrf2 activation. In conclusion, baicalin effectively improved Aβ-induced learning and memory deficit, hippocampus injury, and neuron apoptosis, making it a promising drug to preventive interventions for AD. [ABSTRACT FROM AUTHOR]

Highlights: [•] High levels of COX-2 and caspase-3 and cognitive deficits were detected in injury. [•] Progesterone reduces the expressions of COX-2 and caspase-3 after brain injury. [•] Progesterone improves cognitive functional outcomes after brain injury. [•] The progesterone mechanism is associated with inhibiting inflammation and apoptosis. [ABSTRACT FROM AUTHOR]

Recent studies have shown that reactive oxygen species (ROS) play a crucial role in Se-induced cell apoptosis. A number of studies have demonstrated that perturbed cellular calcium homeostasis has been implicated in apoptosis. The main objective of this study was to evaluate the role of Ca2+ in Na2SeO3-induced apoptosis and the relationship between Ca2+ and ROS in human colonic carcinoma cells SW480. When SW480 cells were exposed to 25–100 μM Na2SeO3, both cell apoptosis and growth inhibition were observed by flow cytometric analysis and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Na2SeO3 was able to induce increase of [Ca2+]i and ROS production and disrupt mitochondrial membrane potential (ΔΨm) in SW480 cells monitored by using a confocal laser scanning microscope. Ca2+ channel inhibitor CoCl2 and an intracellular Ca2+ chelator o-phtalaldehyde, 1,2-bis(2-aminophenoxy)-ethane-N,N,N′,N′-tetra-acetic acid acetoxymethyl ester (BAPTA) completely inhibited [Ca2+]i increase, but catalase had no effect on Na2SeO3-induced increase of [Ca2+]i. BAPTA-AM, CoCl2, and mitochondrial Ca2+ uptake inhibitor ruthenium red blocked ΔΨm dissipation. The increase of ROS was also suppressed by CoCl2, BAPTA, ruthenium red, N-acetylcysteine and catalase, respectively. The mitochondrial uncoupler carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP) completely inhibited Na2SeO3-induced ROS increase. This showed that ROS increase is due to mitochondrial Ca2+ overload. The Na2SeO3-induced apoptosis of SW480 cells was also inhibited by CoCl2, BAPTA, ruthenium red, N-acetylcysteine, and catalase, respectively. The results mentioned above imply that both calcium and Ca2+-dependent ROS as a signal molecule mediate apoptosis induced by Na2SeO3 in SW480 cells. [Copyright &y& Elsevier]

The insulin like growth factor 1 (IGF-1) and its receptor (IGF-1R) facilitate tumor proliferation and progression. Tanshinone IIA (TSN) is an active diterpene quinone isolated from the roots of the herbal plant Salvia miltiorrhiza. TSN inhibits the proliferation of various types of cancer cells but its role in the IGF-1R-induced proliferation of pheochromocytoma (PC12) cells and the potential mechanisms are largely unknown. This study aims to investigate the anti-proliferative effect of TSN in PC12 cells and its role on IGF-1R signaling transduction. PC12 cells were treated with IGF-1 with or without TSN, methyl thiazolytetrazolium (MTT) assay, and cell counting kit-8 and flow cytometry were used to evaluate the proliferation of PC12 cells. The role of TSN on the apoptosis of PC12 cells were detected by flow cytometry as well. The effects of TSN and IGF-1 on the phosphorylation of IGF-1R, protein kinase B (Akt), extracellular-signal related kinase 1/2 (ERK1/2) and other downstream targets were analyzed by Western blotting analysis. Our results showed that IGF-1 promoted the growth of PC12 cells in a dose-dependent manner and increased the phosphorylation of IGF-1R, whereas TSN attenuated the effect of IGF-1. Interestingly, TSN did not induce cell apoptosis in PC12 cells. Moreover, TSN attenuated the phosphorylation of Akt and ERK1/2 induced by IGF-1, and the phosphorylation of glycogen synthase kinase-3β, forkhead box O3a (FOXO3a) and c-Raf were also inhibited by TSN. Furthermore, TSN inhibited cell growth induced by IGF-1 and blocked the activation of IGF-1R in SH-SY5Y cells. Taken together, TSN has an inhibitory effect on the proliferation of PC12 cells via down-regulation of the phosphorylated IGF-1R and its downstream signaling. [ABSTRACT FROM AUTHOR]

Purpose: Mitogen-activated protein kinases (MAPK), specifically the c-Jun N-terminal kinase (JNK)–MAPK subfamily, play a crucial role in the development of various cancers, including hepatocellular carcinoma (HCC). However, the specific roles of JNK1/2 and their upstream regulators, MKK4/7, in HCC carcinogenesis remain unclear. Methods: In this study, we performed differential expression analysis of JNK–MAPK components at both the transcriptome and protein levels using TCGA and HPA databases. We utilized Kaplan–Meier survival plots and receiver operating characteristic (ROC) curve analysis to evaluate the prognostic performance of a risk scoring model based on these components in the TCGA-HCC cohort. Additionally, we conducted immunoblotting, apoptosis analysis with FACS and soft agar assays to investigate the response of JNK–MAPK pathway components to various death stimuli (TRAIL, TNF-α, anisomycin, and etoposide) in HCC cell lines. Results: JNK1/2 and MKK7 levels were significantly upregulated in HCC samples compared to paracarcinoma tissues, whereas MKK4 was downregulated. ROC analyses suggested that JNK2 and MKK7 may serve as suitable diagnostic genes for HCC, and high JNK2 expression correlated with significantly poorer overall survival. Knockdown of JNK1 enhanced TRAIL-induced apoptosis in hepatoma cells, while JNK2 knockdown reduced TNF-α/cycloheximide (CHX)—and anisomycin-induced apoptosis. Neither JNK1 nor JNK2 knockdown affected etoposide-induced apoptosis. Furthermore, MKK7 knockdown augmented TNF-α/CHX- and TRAIL-induced apoptosis and inhibited colony formation in hepatoma cells. Conclusion: Targeting MKK7, rather than JNK1/2 or MKK4, may be a promising therapeutic strategy to inhibit the JNK–MAPK pathway in HCC therapy. [ABSTRACT FROM AUTHOR]

The function of microRNA‐27a (miR‐27a) on synovial angiogenesis and chondrocyte apoptosis in rats with knee osteoarthritis (KOA) by targeting PLK2 is explored in this present study. The rat model of KOA was conducted by anterior cruciate ligament transection. Rats were injected with miR‐27a mimics, mimics NC, pcDNA3.1‐PLK2 pcDNA3.1, or RLK2 RNAi plasmid via tail vein. A series of assays were used to figure out the functions of miR‐27a and PLK2 in synovial angiogenesis and chondrocyte apoptosis in rats with KOA. Furthermore, the putative binding site between miR‐27a and PLK2 was determined. Downregulated miR‐27a was found in synovial tissues and cartilage tissues of KOA rats. Upregulated miR‐27a and downregulated PLK2 inhibited synovial injury and promoted apoptosis of synovial cells, inhibited synovial angiogenesis, inhibited cartilage injury and chondrocyte apoptosis, inhibited cartilage collagen destruction, and alleviates inflammatory injury of synovial tissue and cartilage tissue in KOA rats. Overexpression of PLK2 reverses the effect of upregulation of miR‐27a on synovial angiogenesis and chondrocyte injury in KOA rats. Our study suggests that upregulation of miR‐27a inhibits synovial angiogenesis and chondrocyte apoptosis in KOA rats through the inhibition of PLK2. [ABSTRACT FROM AUTHOR]

Various research studies have been conducted in deducing the role of microRNAs (miRNAs) in the pathogenesis and physiological processes of various systematic diseases. This study aims at demonstration of the important role played by miR‐29a‐3p, through association with phosphatase and tensin homolog (PTEN), in the regulation of abdominal aortic aneurysm development and progression. Quantitative real‐time polymerase chain reaction (RT‐qPCR) examined miRNA‐19a‐3p and PMEPA1 expression in multiplied vascular smooth muscle cells (VSMCs). Cell transfection upregulated or downregulated the genes and cell counting kit‐8 assay determined cellular viability. RT‐qPCR detected cellular proliferation and cell death using the cell proliferation and apoptosis biomarkers Ki87 and proliferating cell nuclear antigen, caspase‐8 and caspase‐3, respectively. Furthermore, luciferase assay analyzed the luciferase activity and western blot analysis determined miRNA‐19a‐3p and PMEPA1 protein expression in proliferation and apoptosis biomarkers. TargetScan 4.2 online software (www.targetscan.org) was used to perform the bioinformatics analysis so as to forecast the putative targets of miR‐29a‐3p and PTEN. The results inferred that there was an increased expression of miRNA‐29a‐3p found in AAA‐mimic cells with increased cellular viability and significant pathological apoptosis. Further, when the expression of miRNA‐29a‐3p was downregulated, it reduced the cell viability of AAA cells. On the basis of the gene interplays, it can be understood that the PTEN was directly targeted by miRNA‐29a‐3p so as to regulate the AAA progression. Thus, PTEN was found to strengthen the proliferation effect of miRNA‐29a‐3p in AAA cells. The current study thus shed more insights about the molecular mechanistic roles of miRNA‐29a‐3p and PTEN, opening doors for novel therapeutic approach to AAA. [ABSTRACT FROM AUTHOR]

Numerous plant viruses that cause significant agricultural problems are persistently transmitted by insect vectors. We wanted to see if apoptosis was involved in viral infection process in the vector. We found that a plant reovirus (rice gall dwarf virus, RGDV) induced typical apoptotic response during viral replication in the leafhopper vector and cultured vector cells, as demonstrated by mitochondrial degeneration and membrane potential decrease. Fibrillar structures formed by nonstructural protein Pns11 of RGDV targeted the outer membrane of mitochondria, likely by interaction with an apoptosis-related mitochondrial protein in virus-infected leafhopper cells or nonvector insect cells. Such association of virus-induced fibrillar structures with mitochondria clearly led to mitochondrial degeneration and membrane potential decrease, suggesting that RGDV Pns11 was the inducer of apoptotic response in insect vectors. A caspase inhibitor treatment and knockdown of caspase gene expression using RNA interference each reduced apoptosis and viral accumulation, while the knockdown of gene expression for the inhibitor of apoptosis protein improved apoptosis and viral accumulation. Thus, RGDV exploited caspase-dependent apoptotic response to promote viral infection in insect vectors. For the first time, we directly confirmed that a nonstructural protein encoded by a persistent plant virus can induce the typical apoptotic response to benefit viral transmission by insect vectors. [ABSTRACT FROM AUTHOR]

Current phosphodiesterase-4 (PDE4) inhibitors exert beneficial effects in central nervous system diseases via anti-inflammatory and anti-apoptotic properties, but many of them are plagued by side effects like nausea and emesis. FCPR16, a novel PDE4 inhibitor synthesized in our lab, has potential anti-inflammatory property. In the present study, we aimed to investigate the effects of FCPR16 in a rat model of ischemic stroke and evaluate its emetogenic potential. Our results showed that FCPR16 treatment improved neurological function, reduced cerebral infarct volume, and attenuated brain histological changes in rats subjected to middle cerebral artery occlusion and reperfusion (MCAO/R). Furthermore, levels of proinflammatory cytokines tumor necrosis factor α, interleukin-6 and interleukin-1β were decreased after FCPR16 treatment, as well as the ionized calcium-binding adapter molecule 1 and glial fibrillary acidic protein in MCAO/R rats. TUNEL staining and Western blot results showed that FCPR16 reduced apoptosis and regulated apoptotic-related proteins, with increased level of phosphorylated protein kinase B. Moreover, FCPR16 treatment increased cyclic adenosine monophosphate (cAMP) levels and cAMP-response element binding protein (CREB) phosphorylation in ischemic tissue. In addition, oral administration of 3 mg/kg FCPR16 did not cause vomiting in beagle dogs. This study indicates that FCPR16 has protective effects against cerebral ischemia-reperfusion injury through inhibiting inflammation and apoptosis via the cAMP/CREB pathway, while it has low emetogenic potential. [ABSTRACT FROM AUTHOR]

Neddylation inhibitor Pevonedistat (MLN4924) is a novel anticancer drug and has demonstrated broad-spectrum anticancer activity. Nevertheless, we found that Pevonedistat had only a modest apoptotic effect in osteosarcoma (OS) cells. Moreover, we noted that inhibition of neddylation by Pevonedistat led to accumulation of Mcl-1 protein in OS cells. Because Mcl-1 is an important anti-apoptotic protein and also because apoptosis has been shown to be a major cell death pathway, we hypothesized that Mcl-1 accumulation negatively impacted Pevonedistat-mediated anticancer activity in OS cells. In this regard, we employed genetic or pharmacological approaches to inhibit Mcl-1 expression and to examine the effect on Pevonedistat-induced apoptosis in OS cells. We found that inhibition of Mcl-1 expression by siRNA considerably enhanced Pevonedistat-triggered the activation of caspase-3, PARP cleavage and apoptosis, and also dramatically promoted the ability of Pevonedistat to inhibit colony formation of OS cells. Moreover, we observed that flavopiridol, a FDA approved drug, inhibited Mcl-1 expression and substantially enhanced Pevonedistat-mediated activation of apoptosis signaling and significantly augmented cell killing effect in OS cells. Altogether, our study shows that Mcl-1 is a critical resistance factor to Pevonedistat monotherapy, and suggests that Pevonedistat in combinations with flavopiridol may achieve better anticancer therapy. [ABSTRACT FROM AUTHOR]

Quercetin, a natural flavonoid, has been reported to prevent pancreatic β-cell apoptosis in animal models of diabetes. However, the underlying mechanism remains unclear. We investigated the mechanisms through which quercetin protects β cells from palmitate-induced apoptosis and determined whether autophagy is involved in this process. We found that quercetin treatment partially reduced palmitate-induced β-cell apoptosis. This protective effect was abolished by pharmacologic inhibition of autophagy and by silencing a key autophagy gene. Further analysis revealed that palmitate treatment promoted the expression of LC3 II, a marker of autophagosomes, but resulted in the blockade of autophagic flux due to lysosome dysfunction. Defective lysosome accumulation can cause lysosomal membrane permeabilization and the release of cathepsins from lysosome into the cytosol that triggers apoptosis. Treatment with quercetin reversed lysosomal dysfunction and promoted autophagosome-lysosome fusion, which restored defective autophagic flux and provoked autophagy. Overall, our results indicate that lysosomal dysfunction is a major factor that contributes to β-cell apoptosis and demonstrates that quercetin improves cell survival by restoring lysosomal function and autophagic flux. This study provides new evidence regarding the anti-apoptotic mechanism of quercetin in the treatment of type 2 diabetes. [ABSTRACT FROM AUTHOR]

The article presents a study on human cytomegalovirus, a pathogen that can cause life-threatening diseases. It notes that this ubiquitous beta-herpes virus carries regulatory proteins such as IE72 and IE82 during infections that affects the majority of population. It states that with this, a Tet-On system was used to measure the effect of IE86 on apoptosis. The result shows inhibition of tumor necrosis factor of IE86 and IE86 does not affect micro RNA level.

Background: Bone marrow-derived mesenchymal stem cell (BMSC) transplantation is one of the new therapeutic strategies for treating ischemic brain and heart tissues. However, the poor survival rate of transplanted BMSCs in ischemic tissue, due to high levels of reactive oxygen species (ROS), limits the therapeutic efficacy of this approach. Considering that BMSC survival may greatly enhance the effectiveness of transplantation therapy, development of effective therapeutics capable of mitigating oxidative stress-induced BMSC apoptosis is an important unmet clinical need. Methods: BMSCs were isolated from the 4-week-old male Sprague Dawley rats by whole bone marrow adherent culturing, and the characteristics were verified by morphology, immunophenotype, adipogenic, and osteogenic differentiation potential. BMSCs were pretreated with artemisinin, and H2O2 was used to induce apoptosis. Cell viability was detected by MTT, FACS, LDH, and Hoechst 33342 staining assays. Mitochondrial membrane potential (ΔΨm) was measured by JC-1 assay. The apoptosis was analyzed by Annexin V-FITC/PI and Caspase 3 Activity Assay kits. ROS level was evaluated by using CellROX® Deep Red Reagent. SOD, CAT, and GPx enzymatic activities were assessed separately using Cu/Zn-SOD and Mn-SOD Assay Kit with WST-8, Catalase Assay Kit, and Total Glutathione Peroxidase Assay Kit. The effects of artemisinin on protein expression of BMSCs including p-Erk1/2, t-Erk1/2, p-c-Raf, p-p90rsk, p-CREB, BCL-2, Bax, p-Akt, t-Akt, β-actin, and GAPDH were measured by western blotting. Results: We characterized for the first time the protective effect of artemisinin, an anti-malaria drug, using oxidative stress-induced apoptosis in vitro, in rat BMSC cultures. We found that artemisinin, at clinically relevant concentrations, improved BMSC survival by reduction of ROS production, increase of antioxidant enzyme activities including SOD, CAT, and GPx, in correlation with decreased Caspase 3 activation, lactate dehydrogenase (LDH) release and apoptosis, all induced by H2O2. Artemisinin significantly increased extracellular-signal-regulated kinase 1/2 (Erk1/2) phosphorylation, in a concentration- and time-dependent manner. PD98059, the specific inhibitor of the Erk1/2 pathway, blocked Erk1/2 phosphorylation and artemisinin protection. Similarly, decreased expression of Erk1/2 by siRNA attenuated the protective effect of artemisinin. Additionally, when the upstream activator KRAS was knocked down by siRNA, the protective effect of artemisinin was also blocked. These data strongly indicated the involvement of the Erk1/2 pathway. Consistent with this hypothesis, artemisinin increased the phosphorylation of Erk1/2 upstream kinases proto-oncogene c-RAF serine/threonine-protein kinase (c-Raf) and of Erk1/2 downstream targets p90 ribosomal s6 kinase (p90rsk) and cAMP response element binding protein (CREB). In addition, we found that the expression of anti-apoptotic protein B cell lymphoma 2 protein (BcL-2) was also upregulated by artemisinin. Conclusion: These studies demonstrate the proof of concept of artemisinin therapeutic potential to improve survival in vitro of BMSCs exposed to ROS-induced apoptosis and suggest that artemisinin-mediated protection occurs via the activation of c-Raf-Erk1/2-p90rsk-CREB signaling pathway. [ABSTRACT FROM AUTHOR]