ML-7 amplifies the quinocetone-induced cell death through akt and MAPK-mediated apoptosis on HepG2 cell line.

The study aims at evaluating the combination of the quinocetone and the ML-7 in preclinical hepatocellular carcinoma models. To this end, the effect of quinocetone and ML-7 on apoptosis induction and signaling pathways was analyzed on HepG2 cell lines. Here, we report that ML-7, in a nontoxic concentration, sensitized the HepG2 cells to quinocetone-induced cytotoxicity. Also, ML-7 profoundly enhances quinocetone-induced apoptosis in HepG2 cell line. Mechanistic investigations revealed that ML-7 and quinocetone act in concert to trigger the cleavage of caspase-8 as well as Bax/Bcl-2 ratio up-regulation and subsequent cleavage of Bid, capsases-9 and -3. Importantly, ML-7 weakened the quinocetone-induced Akt pathway activation, but strengthened the phosphorylation of p-38, ERK and JNK. Further treatment of Akt activator and p-38 inhibitor almost completely abolished the ML-7/quinocetone-induced apoptosis. In contrast, the ERK and JNK inhibitor aggravated the ML-7/quinocetone-induced apoptosis, indicating that the synergism critically depended on p-38 phosphorylation and HepG2 cells provoke Akt, ERK and JNK signaling pathways to against apoptosis. In conclusion, the rational combination of quinocetone and ML-7 presents a promising approach to trigger apoptosis in hepatocellular carcinoma, which warrants further investigation.

AKT/TSC2/p70S6K signaling pathway is involved in quinocetone-induced death-promoting autophagy in HepG2 cells.

Quinocetone (QCT, 3-methyl-2-quinoxalin benzenevinylketo-1, 4-dioxide) is widely used as a veterinary drug and animal feed additive in China. Although it promotes growth and improves feed efficiency, QCT's in vitro and in vivo toxicities remain uncertain. This study was conducted to explore the mechanism of QCT-induced autophagy in HepG2 cells. By the results obtained from monodansylcadaverine (MDC) staining, ultrastructural observation by transmission electron microscopy (TEM), as well as Western blotting analysis for LC3, p62, and Beclin-1, it was demonstrated that QCT induced autophagy in HepG2 cells. Furthermore, PI3K/AKT inhibitor significantly enhanced QCT-induced autophagy, while TSC2 knockdown attenuated this process. In addition, inhibition of autophagy by pharmacological approach remarkably increased the viability of QCT-treated cells detected by MTT assay, suggesting that QCT-triggered autophagy may play as a promotion mechanism for cell death. Meanwhile, apoptosis was markedly downregulated after autophagy blockage, and evaluated by flow cytometry and Western blotting analysis for caspase-3 cleavage. Consequently, these results suggested that QCT-induced autophagy was mediated by AKT/TSC2/p70S6K signaling pathway, and inhibition of autophagy promoted QCT-treated cell survival by attenuating apoptosis.

Lycopene attenuates colistin-induced nephrotoxicity in mice via activation of the Nrf2/HO-1 pathway.

Nephrotoxicity is the major dose-limiting factor for the clinical use of colistin against multidrug-resistant (MDR) Gram-negative bacteria. This study aimed to investigate the protective effect of lycopene on colistin-induced nephrotoxicity in a mouse model. Fifty mice were randomly divided into 5 groups: the control group (saline solution), the lycopene group (20 mg/kg of body weight/day administered orally), the colistin group (15 mg/kg/day administered intravenously), the colistin (15 mg/kg/day) plus lycopene (5 mg/kg/day) group, and the colistin (15 mg/kg/day) plus lycopene (20 mg/kg/day) group; all mice were treated for 7 days. At 12 h after the last dose, blood was collected for measurements of blood urea nitrogen (BUN) and serum creatinine levels. The kidney tissue samples were obtained for examination of biomarkers of oxidative stress and apoptosis, histopathological assessment, and quantitative reverse transcription-PCR (qRT-PCR) analysis. Colistin treatment significantly increased concentrations of BUN and serum creatinine, tubular apoptosis/necrosis, lipid peroxidation, and heme oxygenase 1 (HO-1) activity, while the treatment decreased the levels of endogenous antioxidant biomarkers glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Notably, the changes in the levels of all biomarkers were attenuated in the kidneys of mice treated with colistin by lycopene (5 or 20 mg/kg). Lycopene treatment, especially in the colistin plus lycopene (20 mg/kg) group, significantly downregulated the expression of NF-κB mRNA (P < 0.01) but upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1 mRNA (both P < 0.01) in the kidney compared with the results seen with the colistin group. Our data demonstrated that coadministration of 20 mg/kg/day lycopene can protect against colistin-induced nephrotoxicity in mice. This effect may be attributed to the antioxidative property of lycopene and its ability to activate the Nrf2/HO-1 pathway.

Arsanilic acid causes apoptosis and oxidative stress in rat kidney epithelial cells (NRK-52e cells) by the activation of the caspase-9 and -3 signaling pathway.

Arsenic exists widely in rock, water and air, and arsanilic acid (also known as aminophenyl arsenic acid) is an organoarsenic compound and has been used as feed additives. Organoarsenic compounds in foodstuff cause adverse effects, including acute and chronic toxicity, in animals and humans. However, little is known about the cellular toxicity and mechanisms of organic arsenic on the kidney. In this study, we explored the toxicity and molecular mechanisms of arsanilic acid on rat kidney epithelial cells (NRK-52e cells). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that arsanilic acid inhibited the proliferation of rat NRK-52e cells in a dose-dependent manner, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and flow cytometry revealed that arsanilic acid induced cellular apoptosis in NRK-52e cells. Fluorescence spectrophotometer displayed that arsanilic acid caused a loss of mitochondrial transmembrane potential (MMP) of NRK-52e cells, but enhanced reactive oxygen species level of these cells. Notably, trolox, a water-soluble derivative of vitamin E, protected NRK-52e cells against MMP loss and apoptosis caused by arsanilic acid. Western blots with caspase inhibitors further indicated that arsanilic acid increased expression of active caspase-3 and -9 in NRK-52e cells. Collectively, these results suggest that arsanilic acid causes apoptosis and oxidative stress in rat kidney epithelial cells through activation of the caspase-9 and -3 signaling pathway. This study thus provides a novel insight into molecular mechanisms by which arsanilic acid has adverse cytotoxicity on renal tubular epithelial cells.

Inhibition of autophagy promotes caspase-mediated apoptosis by tunicamycin in HepG2 cells.

Tunicamycin (TM) causes accumulation of unfolded protein in endoplasmic reticulum (ER) lumen and introduces from elsewhere ER stress. This study was to assess the apoptosis and autophagy effect induced by TM on HepG2 cells and the role of autophagy in the system. The viability of HepG2 cells was significantly inhibited by TM in a dose-dependent manner detected by MTT assay. Then, the apoptotic morphology change, increasing apoptotic cell rate suggested that apoptosis was induced by TM in a time- and dose-dependent manner. To further determine the involvement of caspase-dependent pathway in TM-induced apoptosis, we discover that the activity of caspase-3/7, 8, 9 and cleavage of PARP markedly increased after TM treatment and the apoptosis was effectively attenuated by using caspase-9 and pan caspase inhibitor. Moreover, provided the rising stained acidic vacuoles and an increased level of LC3II and activation of Beclin1, we concluded that autophagy could be triggered by TM in a time- and dose-dependent manner. In addition, the inhibition of autophagy efficiently promoted TM-induced cell death identified by MTT assay. Meanwhile, the apoptotic cell rate and caspase-3 activation increased significantly after autophagy blockage. In conclusion, we found that TM initiated apoptosis and autophagy both in a time- and dose-dependent manner in HepG2 cells; and inhibition of autophagy may promote TM-induced cell death through enhancing apoptosis.

Novel insights into the roles of migrasome in cancer.

Cell migration, a hallmark of cancer malignancy, plays a critical role in cancers. Improperly initiated or misdirected cell migration can lead to invasive metastatic cancer. Migrasomes are newly discovered vesicular cellular organelles produced by migrating cells and depending on cell migration. Four marker proteins [NDST1 (bifunctionalheparan sulfate N-deacetylase/N-sulfotransferase 1), EOGT (Epidermal growth factor domains pecific O-linked N-acetylglucosaminetransferase), CPQ (carboxypeptidase Q), and PIGK (phosphatidylinositol glycan anchor biosynthesis, class K)] of migrasomes were successfully identified. There are three marker proteins (NDST1, PIGK, and EOGT) of migrasome expressed in cancer. In this review, we will discuss the process of migrasome discovery, the formation of migrasome, the possible functions of migrasome, and the differences between migrasomes and exosomes, especially, the biological functions of migrasome marker proteins in cancer, and discuss some possible roles of migrasomes in cancer. We speculate that migrasomes and migracytosis can play key roles in regulating the development of cancer.

The Impact of miR-122 on Cancer.

MiRNAs are confirmed to be a kind of short and eminently conserved noncoding RNAs, which regulate gene expression at the post-transcriptional level via binding to the 3'- untranslated region (3'-UTR) of targeting multiple target messenger RNAs. Recently, growing evidence stresses the point that they play a crucial role in a variety of pathological processes, including human cancers. Dysregulated miRNAs act as oncogenes or tumor suppressor genes in many cancer types. Among them, we noticed that miR-122 has been widely reported to significantly influence carcinogenicity in a variety of tumors by regulating target genes and signaling pathways. Here, we focused on the expression of miR-122 in regulatory mechanisms and tumor biological processes. We also discussed the effects of miR-122 dysregulation in various types of human malignancies and the potential to develop new molecular miR-122-targeted therapies. The present review suggests that miR-122 may be a potentially useful cancer diagnosis and treatment biomarker. More clinical diagnoses need to be further launched in the future. A promising direction to improve the outcomes for cancer patients will likely combine miR-122 with other traditional tumor biomarkers.

Microrna-96 In Human Cancers.

MicroRNAs (miRNAs) are small non-coding RNAs 19-25 nucleotides in size involved in gene regulation and diverse processes in tumor cells. Abnormal expression of miRNAs is closely related to carcinogenesis. MiR-96 is a salient cancer-related miRNA in a variety of tumors. Recent evidence indicates that miR-96 has been observed to be wrapped in exosome and associated with drug resistance or radio-chemosensitivity in cancers. miR-96 is also inextricably linked with the competing endogenous RNAs (ceRNAs) in cancers. Notably, miR-96 plays both a tumor suppressor role and plays a carcinogenic role in the same cancers. This review summarizes the critical role of cancer-related miR-96 in drug resistance or radio-chemosensitivity and ceRNA mechanisms of miR-96 in cancer. And we innovatively propose that miR-96 has a yin-yang effect in cancers. Based on these several major roles of miR-96 in cancer as described above, we speculate that the abnormal expression of miR-96 is likely to be novel potential therapeutic targets in cancers. It is expected to solve the treatment problems such as low chemoradiotherapy sensitivity, poor prognosis quality of life and easy recurrence in cancer patients.

Emerging roles of noncoding RNAs in human cancers.

Studies have found that RNA encoding proteins only account for a small part of the total number, most RNA is non-coding RNA, and non-coding RNA may affect the occurrence and development of human cancers by affecting gene expression, therefore play an important role in human pathology. At present, ncRNAs studied include miRNA, circRNA, lncRNA, piRNA, and snoRNA, etc. After decades of research, the basic role of these ncRNAs in many cancers has been clear. As far as we know, the role of miRNAs in cancer is one of the hottest research directions, however, it is also found that the imbalance of ncRNAs will affect the occurrence of gastric cancer, breast cancer, lung cancer, meanwhile, it may also affect the prognosis of these cancers. Therefore, the study of ncRNAs in cancers may help to find new cancer diagnostic and treatment methods. Here, we reviewed the biosynthesis and characteristics of miRNA, cricRNA, and lncRNA etc., their roles in human cancers, as well as the mechanism through which these ncRNAs affect human cancers.

Effect of the Application of Exosome on Gastric Cancer.

Gastric cancer is one of the most common and highest mortality rate cancers in the world. Exosomes are vesicles secreted by cells carrying different types of molecules, such as protein and RNA. Numerous studies have confirmed that exosomes are involved in various stages of the occurrence and development of gastric cancer and play an important role. With the gradual development, exosomes have been widely employed in the diagnosis and treatment of gastric cancer. In this review, we have provided a basic overview of exosome, and discussed the role of exosome in the occurrence, proliferation, invasion, metastasis, and drug resistance in gastric cancer. In addition, we have emphasized the bright development prospect of exosome in the diagnosis and treatment of gastric cancer. The data on the discovery, diagnosis, treatment, and prognosis of gastric cancer are not particularly optimistic, but the discovery of exosome, applied in diagnosis and treatment, provides a new and effective way to improve the survival rate of patients with gastric cancer.

Zearalenone induces apoptosis and necrosis in porcine granulosa cells via a caspase-3- and caspase-9-dependent mitochondrial signaling pathway.

Zearalenone is a mycotoxin produced mainly by Fusarium. There are numerous incidences of mycotoxicosis in laboratory and domestic animals, especially in pigs. However, little is known about molecular mechanisms of zearalenone toxicity. Granulosa cells are the maximal cell population in follicles, and they play an essential role in the development and maturation of follicles. The objective of this study was to explore the effect of zearalenone at high concentrations on proliferation and apoptosis of porcine granulosa cells and uncover signaling pathway underlying the cytotoxicity of zearalenone. We found that zearalenone reduced the proliferation of porcine granulosa cells in a dose-dependent manner as shown by the MTT assay and zearalenone resulted in an obvious apoptosis and necrosis in porcine granulosa cells as determined by the TUNEL analysis and flow cytometry. In addition, TUNEL assay with caspase inhibitors showed that zearalenone triggered a caspase-3- and caspase-9-dependent apoptotic process in porcine granulosa cells. Fluorescence spectrophotometer displayed that zearalenone led to a loss of mitochondrial transmembrane potential of porcine granulosa cells but enhanced reactive oxygen species (ROS) levels of the cells. Notably, Western blots revealed that caspase-3 and caspase-9 were activated by zearalenone in porcine granulosa cells. Collectively, our results suggest that zearalenone induces apoptosis and necrosis of porcine granulosa cells in a dose-dependent manner via a caspase-3- and caspase-9-dependent mitochondrial pathway. This study thus offers a novel insight into molecular mechanisms by which zearalenone has adverse cytotoxicity on reproduction.

Cytoprotective effect of trolox against oxidative damage and apoptosis in the NRK-52e cells induced by melamine.

An outbreak of urinary stones associated with consumption of melamine-tainted milk products occurred in 2008 in China, leading to serious illness of many infants and even death. However, the toxicity of melamine in kidney epithelial cells remains unclear. We have explored the effects of melamine and trolox on renal NRK-52e (normal rat kidney 52e) cells. The IC(50) of melamine was measured by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. Total SOD (superoxide dismutase) was determined by NBT (Nitro Blue Tetrazolium) staining method. GSH-Px (glutathione peroxidase) activity was detected by UV colorimetric assay, and MDA (malondialdehyde) content was determined by thiobarbituric acid assay. Apoptosis induced by melamine was determined by flow cytometry. The IC(50) increased when NRK-52e cells were treated with both melamine and trolox compared with melamine only. SOD and GSH-Px activities were decreased, but MDA content was increased by melamine in a dose-dependent manner. Trolox significantly enhanced SOD and GSH-Px activity in melamine-treated NRK-52e cells, but it decreased their MDA content. LDH (lactate dehydrogenase) activity and the level of ROS (reactive oxygen species) of the NRK-52e cells were enhanced by melamine compared with the control. Furthermore, the apoptosis rate increased in NRK-52e cells treated with melamine, whereas trolox was protective. These results show that melamine has an obvious adverse effect on proliferation of NRK-52e cells, causing oxidative damage and apoptosis, thus providing a novel insight into renal cytotoxicology of melamine. Trolox ameliorates the effect on melamine toxicity.

The Role of NcRNAs to Regulate Immune Checkpoints in Cancer.

At present, the incidence of cancer is becoming more and more common, but its treatment has always been a problem. Although a small number of cancers can be treated, the recurrence rates are generally high and cannot be completely cured. At present, conventional cancer therapies mainly include chemotherapy and radiotherapy, which are the first-line therapies for most cancer patients, but there are palliatives. Approaches to cancer treatment are not as fast as cancer development. The current cancer treatments have not been effective in stopping the development of cancer, and cancer treatment needs to be imported into new strategies. Non-coding RNAs (ncRNAs) is a hot research topic at present. NcRNAs, which include microRNAs (miRNAs), circular RNAs (circRNAs), and long non-coding RNAs (lncRNAs), participate in all aspects of cancer biology. They are involved in the progression of tumors into a new form, including B-cell lymphoma, glioma, or the parenchymal tumors such as gastric cancer and colon cancer, among others. NcRNAs target various immune checkpoints to affect tumor proliferation, differentiation, and development. This might represent a new strategy for cancer treatment.

Tumor-derived or non-tumor-derived exosomal noncodingRNAs and signaling pathways in tumor microenvironment.

The tumor microenvironment (TME) involved in multiple pathological processes of tumors is highly complex. Exosomes, as organelles, can be produced by some cells in the TME and have been verified as a special carriers and a key factor for communication between tumor and TME-associated cells. Noncoding RNAs (ncRNAs) involved in tumorigenesis and development have been demonstrated to be released into the TME by exosomes. However, the detailed regulatory functions of exosomal ncRNAs through signaling pathways in the TME are still unclear. In this review, we systematically summarized the detailed molecular mechanisms by which exosomal ncRNAs mediate the modulation of both tumor cells and nontumor cells. Exosomal ncRNAs in the TME exhibited the potential ability to influence cancer development through signaling pathways, including PTEN signaling, NF-κB signaling, Wnt/ß-catenin signaling, PI3K/AKT signaling, etc. Expressly, considering that research on circRNAs has gained much momentum in recent years, we more thoroughly described the implication of exosomal circRNAs in the regulation of signaling. Our review might hopefully inspire a deeper understanding of exosomal ncRNA function in terms of signaling pathways. We speculated that exosomal ncRNAs, as useful biomarkers and therapeutic targets, play an important role in the diagnosis and prognosis of cancer.

DNA damage and decrease of cellular oxidase activity in piglet Sertoli cells exposed to arsanilic acid.

The study was designed to explore the toxic effects of arsanilic acid on piglet Sertoli cells. Sertoli cells were isolated from piglet testes using a two-step enzyme digestion followed by differential plating. Piglet Sertoli cells were cultured and classified into the following five groups: group A, the control without arsanilic acid treatment; group B, cultured with 5 µM arsanilic acid; group C, cultured with 50 µM arsanilic acid; group D, cultured with 0.5 mM arsanilic acid; and group E, cultured with 5 mM arsanilic acid. We found that Sertoli cell growth was inhibited by arsanilic acid at 0.5 mM compared with the control, group A. The oxidase activity of Sertoli cells was decreased by arsanilic acid at 0.5 mM as evidenced by the observations that arsanilic acid increased MDA content but decreased the SOD and GSH-Px activities of Sertoli cells. Moreover, 50 µM of arsanilic acid was observed to cause DNA damage in Sertoli cells. The results of our study suggest that exposure of Sertoli cells to arsanilic acid leads to induction of oxidative stress and inhibition of cell growth at a high concentration, while arsanilic acid causes DNA damage in Sertoli cells at a low concentration.

Cadmium suppresses the proliferation of piglet Sertoli cells and causes their DNA damage, cell apoptosis and aberrant ultrastructure.

OBJECTIVE: Very little information is known about the toxic effects of cadmium on somatic cells in mammalian testis. The objective of this study is to explore the toxicity of cadmium on piglet Sertoli cells. METHODS: Sertoli cells were isolated from piglet testes using a two-step enzyme digestion and followed by differential plating. Piglet Sertoli cells were identified by oil red O staining and Fas ligand (FasL) expression as assayed by immunocytochemistry and expression of transferrin and androgen binding protein by RT-PCR. Sertoli cells were cultured in DMEM/F12 supplemented with 10% fetal calf serum in the absence or presence of various concentrations of cadmium chloride, or treatment with p38 MAPK inhibitor SB202190 and with cadmium chloride exposure. Apoptotic cells in seminiferous tubules of piglets were also performed using TUNEL assay in vivo. RESULTS: Cadmium chloride inhibited the proliferation of Piglet Sertoli cells as shown by MTT assay, and it increased malondialdehyde (MDA) but reduced superoxide dismutase (SOD) and Glutathione peroxidase (GSH-Px) activity. Inhibitor SB202190 alleviated the proliferation inhibition of cadmium on piglet Sertoli cells. Comet assay revealed that cadmium chloride caused DNA damage of Piglet Sertoli cells and resulted in cell apoptosis as assayed by flow cytometry. The in vivo study confirmed that cadmium induced cell apoptosis in seminiferous tubules of piglets. Transmission electronic microscopy showed abnormal and apoptotic ultrastructure in Piglet Sertoli cells treated with cadmium chloride compared to the control. CONCLUSION: cadmium has obvious adverse effects on the proliferation of piglet Sertoli cells and causes their DNA damage, cell apoptosis, and aberrant morphology. This study thus offers novel insights into the toxicology of cadmium on male reproduction.

Surface plasmon resonance biosensor for the determination of 3-methyl-quinoxaline-2-carboxylic acid, the marker residue of olaquindox, in swine tissues.

To monitor the illegal use of olaquindox in animals, a monoclonal antibody-based surface plasmon resonance (SPR) biosensor method has been developed to detect 3-methyl-quinoxaline-2-carboxylic acid, the marker residues of olaquindox, in swine tissues. The limit of detection was 1.4 µg kg-1 in swine muscle and 2.7 µg kg-1 in swine liver, which are lower than the EU recommended concentration (10 µg kg-1). The recoveries were from 82% to 104.6%, with coefficients of variation of less than 12.2%. Good correlations between SPR and HPLC results (r = 0.9806, muscle; r = 0.9698, liver) and between SPR and ic-ELISA results (r = 0.9918, muscle; r = 0.9873, liver) were observed in the affected tissues, which demonstrated the reliability of the SPR method. This method would be a rapid and reliable tool for the screening of the residues of olaquindox in the edible tissues of animals.

Transforming Growth Factor-ß-Neutralizing Antibodies Improve Alveolarization in the Oxygen-Exposed Newborn Mouse Lung.

Abnormal alveolar formation and excessive disordered elastin accumulation are key pathological features in bronchopulmonary dysplasia. Transforming growth factor (TGF)-ß is an important regulator of the extracellular matrix in the developing lung. To determine if increased TGF-ß would injure alveolar development by activating TGF-ß signaling and by influencing the expression of elastogenesis-related protein, we performed intraperitoneal injection of newborn mice with the TGF-ß-neutralizing antibody 1D11 and observed whether 1D11 had a protective role in the oxygen (O2)-exposed newborn mouse lung. The newborn mice were exposed to 85% O2 for 14 and 21 days. 1D11 was administered by intraperitoneal injection every day from postnatal days 3 to 20. Alveolar morphology was assessed by hematoxylin and eosin staining. The expression and distribution of elastin were evaluated by immunohistochemistry. The level of TGF-ß signaling-related proteins were measured by immunohistochemistry, enzyme-linked immunosorbent assay, and Western blot. The expression levels of elastogenesis-related proteins, including tropoelastin, fibulin-5, and neutrophil elastase (NE), which participate in the synthesis, assembly, and degradation of elastin, were detected by real-time PCR and Western blot. In this research, impaired alveolar development and elastin deposition as well as the excessive activation of TGF-ß signaling were observed in the newborn mouse lung exposed to hyperoxia. 1D11 improved alveolarization as well as the distribution of elastin in the newborn lung with hyperoxia exposure. The expression levels of tropoelastin, fibulin-5, and NE, which are important components of elastogenesis, were decreased by treatment with 1D11 in the injured newborn lung. These data demonstrate that 1D11 improved alveolarization by blocking the TGF-ß signaling pathway and by reducing the abnormal expression of elastogenesis-related proteins in the O2-exposed newborn mouse lung. 1D11 may become a new therapeutic method to prevent the development of bronchopulmonary dysplasia.

Effect of Intranasal Instillation of Lipopolysaccharide on Lung Development and Its Related Mechanism in Newborn Mice.

Premature infants are prone to repeated lung infections after birth, which can disrupt the development of lung structure and function. However, the effects of postnatal pulmonary inflammation on lung development in newborn mice have not been reported and may play an important role in the development of bronchopulmonary dysplasia (BPD). This study aimed to establish a BPD model of postnatal pulmonary inflammation in premature infants and to explore its role and possible mechanisms in the pathogenesis of BPD. We exposed postnatal day 1 mice to lipopolysaccharide (LPS) and normal saline for 14 days. Pulmonary inflammation and alveolar microvascular development were assessed by histology. In addition, we also examined the expression of vascular endothelial growth factor (VEGF), VEGFR2, nuclear factor-kappa-B (NF-κB) and related inflammatory mediators [interleukin-1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein-1α (MIP-1α), monocyte chemoattractant protein-1 (MCP-1)] in the lungs. Lung histology revealed inflammatory cell infiltration, alveolar simplification, and decreased microvascular density in LPS-exposed lungs. VEGF and VEGFR2 expression was decreased in the lungs of LPS-exposed neonatal mice. Furthermore, we detected elevated levels of the inflammatory mediators IL-1ß, TNF-α, MIP-1α, and MCP-1 in the lungs, which are associated with the activation of NF-κB. Intranasal instillation of LPS inhibits lung development in newborn mice, and postnatal pulmonary inflammation may participate in the pathogenesis of BPD. The mechanism is related to the inhibition of VEGF and VEGFR2 and the upregulation of inflammatory mediators through activation of NF-κB.

Quinocetone induces mitochondrial apoptosis in HepG2 cells through ROS-dependent promotion of VDAC1 oligomerization and suppression of Wnt1/ß-catenin signaling pathway.

Quinocetone (QCT) has been used as an animal feed additive in China since 2003. However, investigations indicate that QCT has potential toxicity due to the fact that it shows cytotoxicity, genotoxicity, hepatotoxicity, nephrotoxicity and immunotoxicity in vitro and animal models. Although QCT-induced mitochondrial apoptosis has been established, the molecular mechanism remains unclear. This study was aimed to investigate the role of voltage-dependent anion channel 1 (VDAC1) oligomerization and Wnt/ß-catenin pathway in QCT-induced mitochondrial apoptosis. The results showed VDAC inhibitor 4, 4-diisothiocyano stilbene-2, 2-disulfonic acid (DIDS) partly compromised QCT-induced cell viability decrease (from 34.1% to 68.5%) and mitochondrial apoptosis accompanied by abating VDAC1 oligomerization, cytochrome c (Cyt c) release and the expression levels of cleaved caspase-9, -3 and poly (ADP-ribose) polymerase (PARP). Meanwhile, overexpression VDAC1 exacerbated QCT-induced VDAC1 oligomerization and Cyt c release. In addition, lithium chloride (LiCl), an activator of Wnt/ß-catenin pathway, markedly attenuated QCT-induced mitochondrial apoptosis by partly restoring the expression levels of Wnt1 and ß-catenin. Finally, reactive oxygen species (ROS) scavenger N-acetyl-l-cysteine (NAC) obviously blocked QCT-induced VDAC1 oligomerization and the inhibition of Wnt1/ß-catenin pathway. Taken together, our results reveal that QCT induces mitochondrial apoptosis by ROS-dependent promotion of VDAC1 oligomerization and suppression of Wnt1/ß-catenin pathway.