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Nervous necrosis virus (NNV), the causative agent of viral nervous necrosis (VNN) disease, has caused mass mortality of cultured marine and freshwater fish worldwide, resulting in enormous economic losses in the aquaculture industry. However, the molecular mechanisms underlying the pathogenicity of NNV are still poorly understood. In this study, the transcriptomic profiles of striped snakehead fish (Channa striatus) cells (SSN-1) infected with red-spotted grouper NNV (RGNNV) were investigated using deep RNA sequencing technique. From 254,955,234 raw reads, a total of 253,338,544 clean reads were obtained and they were assembled into 93,372 unigenes. Differentially expressed genes (DEGs) were identified from RGNNV-infected or mock-infected SSN-1 cells, including 1184 up-regulated and 1456 down-regulated genes at 3 h (h) post of infection (poi), and 1138 up-regulated and 2073 down-regulated genes at 24 h poi, respectively. These DEGs were involved in many pathways related to viral pathogenesis, including retinoic acid-inducible gene I (RIG-I) like receptors pathway, apoptosis pathway, oxidative phosphorylation, PI3K-Akt signaling pathway, and MAPK signaling pathway. Subsequent analysis focusing on the apoptosis pathway showed that the expression of Endonuclease G (EndoG) was up-regulated upon RGNNV infection at both 3 and 24 h poi. Therefore, EndoG gene was cloned and its function was further characterized. The results showed that over-expression of EndoG could also induce cellular apoptosis in SSN-1 cells, indicating that RGNNV infection might induce apoptosis of SSN-1 cells via EndoG-associated mitochondrial pathway. These results will shed a new light on the pathogenesis of NNV., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: To investigate the apoptosis inducing effects of ponicidin (PON) on leukemic K562 cells and its mechanisms of action., Method: K562 cells in culture medium in vitro were given different concentrations of PON (10-50 micromol x L(-1)) for 24, 48 and 72 h. The inhibitory rate of the cells was measured by MTT assay, cell apoptotic rates were detected by flow cytometry (FCM) using Annexin V staining after K562 cells were treated with different concentrations of PON for 72 hours, and cell morphology was observed by Wright-Giemsa staining. Western blot was used to detect caspase-3 and poly(ADP-ribose) polymerase (PARP) expression, and the protein levels in mitogen-activated protein kinase signaling pathways (MAPKs, p-P38, p-ERK and p-JNK) as well as p-AKT and p-P85 in PI3K/AKT signaling pathways were also detected., Result: PON (over 30 micromol x L(-1)) could inhibit the growth of K562 cells in both time- and dose-dependent manner. FCM analysis revealed that apoptotic cells were gradually increased in a dose-dependent manner after treatment for 72 hours, and that marked morphological changes of cell apoptosis such as condensation of chromatin was clearly observed by Wright-Giemsa staining after treatment by 50 micromol x L(-1) PON. Western blot showed cleavage of the caspase-3 zymogen protein (32 kD), with the appearance of its 17 kD subunit, and a cleaved 89 kD fragment of 116 kD PARP was also found. Furthermore, Western blotting also showed that expression of p-AKT and p-P85 in PI3K/AKT signaling pathways was downregulated dramatically whereas the expression of p-P38 as well as p-ERK and p-JNK remained unchanged after the cells were treated by PON for 48 h., Conclusion: The results demonstrate that PON exhibits in vitro anti-leukemia effect by induction of apoptosis in K562 cells, and that PON induced apoptosis in K562 cells mainly related to activation of caspase-3 as well as inactivation of PI3K/AKT signaling pathway via down regulation of the expression of p-AKT and p-P85 protein levels. These results provide strong laboratory evidence for further anti-leukemia trials of PON.

• miR-200b-5p is up-regulated and c-myc and SIRT1 are down-regulated in MCAO mice. • c-myc or SIRT1 protects mice from MCAO-induced brain damage. • c-myc binds to the miR-200b-5p promoter to inhibit miR-200b-5p expression. • miR-200b-5p targets and regulates SIRT1 expression. • Down-regulating miR-200b-5p reduces brain damage in MCAO mice. c-myc has been reported to attenuate ischemia stroke (IS). We initiated the research to uncover the molecular mechanism of c-myc with regard to microRNA (miR)-200b-5p/Sirtuin1 (SIRT1) axis. An IS mouse model was prepared by middle cerebral artery occlusion (MCAO). Measurements of c-myc, miR-200b-5p and SIRT1 levels in MCAO mice were conducted. c-myc, miR-200b-5p and SIRT1 expression levels in MCAO mice were detected. The neurological function, production of inflammatory cytokines, neuronal apoptosis, brain tissue pathology and neuronal survival of MCAO mice were observed. c-myc and SIRT1 levels went downward while miR-200b-5p expression went upward in MCAO mice. Elevation of c-myc or suppression of miR-200b-5p improved neurological function, reduced inflammation and neuronal apoptosis, and attenuated brain tissue pathology and neuronal survival of MCAO mice. Enhancement of miR-200b-5p or knockdown of SIRT1 weakened c-myc-induced protection against MCAO-induced brain injury in mice. Overall, c-myc protects mice from IS through elevating miR-200b-5p-targeted SIRT1 expression. [ABSTRACT FROM AUTHOR]

A number of metabolic disorders, including hyperlipidemia, potentially cause chronic kidney disease (CKD), one of their major chronic complications and comorbidities. Rosuvastatin is one of the widely used antiatherogenic drugs among hyperlipidemic patients. Meanwhile, sarpogrelate is not only a 5-hydroxytryptamine receptor antagonist but also an antiplatelet agent, inhibiting platelet-stimulated blood coagulation and improving peripheral circulation. In this study, a combination of sarpogrelate and/or rosuvastatin was used on CKD mice induced by a high-fat diet for 8 weeks. The mice were tested for pathological changes using histological evaluation. Tremendous alterations were found, including a remarked increase in total cholesterol and low-density lipoprotein cholesterol levels, glomerular endothelial proliferation, and mesangial expansion. Also, tubular damage and extracellular matrix accumulation occurred, namely, a marked increase in the macula densa, scattered and apoptotic loss of the apical brush border with vacuolated basophilic cytoplasm and heavily stained nuclei, and expanded Bowman's space, which were at least partially ameliorated by sarpogrelate and/or rosuvastatin treatment. The analysis of expression profiles at both the RNA and protein levels, using real-time quantitative polymerase chain reaction and Western blot analysis, indicated that LDL-R/CD68/LOX-1-positive monocyte/macrophage-mediated enhanced proinflammatory activation, including the significant upregulation of tumor necrosis factor-α and interleukin-6, was actually attenuated by sarpogrelate and/or rosuvastatin treatment. The findings indicated that sarpogrelate and/or rosuvastatin treatment potentially ameliorates CKD progression in patients with the aforementioned comorbid metabolic disorders. [ABSTRACT FROM AUTHOR]

Abstract Giant freshwater prawn Macrobrachium rosenbergii is an economically important species. However, its growth retardant have brought serious economic losses in recent years. Antibiotics abuse is suggested as a reason for M. rosenbergii 's growth retardant, while few studies focused on the toxic effect of antibiotics on M. rosenbergii. To investigate the effect of enrofloxacin, a widely used antibiotic, on juvenile M. rosenbergii , a 14 days exposure study was carried out within 0.2, 1 and 5 mg/L enrofloxacin and followed by 7 days decontamination. Results showed that during the test period, enrofloxacin had the largest accumulation in juvenile shrimp at day 3, and gradually decreased at day 7 and 14, and almost all the drugs are cleared after 3 days decontamination. Short-term exposure to low dose enrofloxacin can promote the growth of juveniles. High dose enrofloxacin inhibited the growth of juvenile shrimp, to gill and liver damage, and induced apoptosis of the hepatopancreatic cells. These adverse effects was possibly caused by enrofloxacin-induced oxidative stress. Moreover, we also found the damage caused by high concentrations of enrofloxacin was irreversible in the short term. Collectively, these data indicated that enrofloxacin did affect the juvenile shrimp growth and development, and high level enrofloxacin abuse may contributed to M. rosenbergii 's growth retardant. Highlights • Low dose enrofloxacin can promote the growth of M. rosenbergii. • High dose enrofloxacin inhibited the growth of M. rosenbergii. • The damaging effects of enrofloxacin is related to oxidative stress. • Damage caused by high dose enrofloxacin was irreversible in the short term. • Enrofloxacin abuse may contributed to M. rosenbergii 's growth retardant. [ABSTRACT FROM AUTHOR]

PIG3 (p53-inducible gene 3), originally identified as one of a set of genes induced by p53 before the onset of apoptosis, was assumed to contribute to early cellular response to DNA damage. Here, we studied the relation between p53 status and the increased expression of PIG3 by ionizing radiation (IR), and the related clues regarding the involvement of PIG3 in the cellular response to IR-induced DNA damage signaling. We demonstrated that the pentanucleotide microsatellite sequence was responsible for the p53-dependent induction of PIG3 transcription after irradiation, while sequence upstream of PIG3 promoter could maintain the basal level of expression which was not inducible by irradiation. The interaction of PIG3 and the KRAB-ZFP-associated protein 1 (KAP1), a DNA damage response protein, was revealed. PIG3 nucleus foci were formed 15 min after γ-ray irradiation, and which were found to partially colocalize with the phospho-KAP-1 foci as well as γ-H2AX foci. Although the lac operator tagged EGFP based reporter system revealed that PIG3 does not remodel chromatin in large scale in the cells under normal growing condition, it indeed prompted the chromatin relaxation in the cellular response to DNA damage signaling. All these data suggest that PIG3 is involved in IR-induced DNA damage response, and which maybe partially attribute to its interaction with KAP1. [ABSTRACT FROM AUTHOR]