IFN-γ affects pancreatic cancer properties by MACC1-AS1/MACC1 axis via AKT/mTOR signaling pathway.

BACKGROUND: Metastasis-related in colon cancer 1 (MACC1) is highly expressed in a variety of solid tumours, but its role in pancreatic cancer (PC) remains unknown. Interferon gamma (IFN-γ) affecting MACC1 expression was explored as the potential mechanism following its intervention. METHODS: Expressions of MACC1 treated with IFN-γ gradient were confirmed by quantitative real-time PCR (qRT-PCR) and western blot (WB). Proliferation, migration, and invasion abilities of PC cells treated with IFN-γ were analysed by CCK8, EDU, colony formation, Transwell (with or without matrix gel) and wound-healing assays. Expression of antisense long non-coding RNA of MACC1, MACC1-AS1, and proteins of AKT/mTOR pathway, (pho-)AKT, and (pho-)mTOR was also assessed by qRT-PCR and WB. SiRNA kit and lentiviral fluid were conducted for transient expression of MACC1 and stable expression of MACC1-AS1, respectively. Rescue assays of cells overexpressing MACC1-AS1 and of cells silencing MACC1 were performed and cellular properties and proteins were assessed by the above-mentioned assays as well. RESULTS: IFN-γ inhibited MACC1 expression in a time- and dose-dependent manner; 100 ng/mL IFN-γ generally caused downregulation of most significant (p ≤ 0.05). In vitro experiments revealed that IFN-γ decreased cellular proliferation, migration, and invasion abilities and downregulated the expression of pho-AKT and pho-mTOR (p ≤ 0.05). Conversely, overexpression of MACC1-AS1 upregulated pho-AKT and pho-mTOR proteins, and reversed cellular properties (p ≤ 0.05). Rescue assays alleviated the above changes of pho-AKT/ mTOR and cellular properties. CONCLUSION: IFN-γ affected PC properties by MACC1-AS1/MACC1 axis via AKT/mTOR signaling pathway, which provides novel insight for candidate targets for treating PC.

P2X7 receptor in the hippocampus is involved in gp120-induced cognitive dysfunction.

To investigate the role of the P2X7 receptor in learning and memory dysfunction induced by HIV-1 envelope glycoprotein gp120 (gp120), we established HIV-1-associated dementia (HAD) animal models by intracerebroventricular (ICV) infusion of gp120 in rats. We observed gp120-induced cognitive dysfunction in the radial arm water maze test. Results showed that rats in the gp120 groups had longer escape latencies and more errors compared to those in the control group. For example, the average trial time in the 50-ng/day-gp120 group on day eight (16.57 ± 1.71 s, N = 90) was significantly longer than that of control rats (9.93 ± 0.68 s, N = 90). The relative expression of P2X7 mRNA in the control, 50-, 70-, and 100-ng/day-gp120 groups were 0.43 ± 0.06, 0.48 ± 0.07, 0.83 ± 0.05, and 0.84 ± 0.10, respectively; relative P2X7 protein expression in those groups was 0.63 ± 0.07, 1.08 ± 0.06, 0.90 ± 0.07, and 1.03 ± 0.11, respectively. According to immunohistochemistry analysis, the staining intensity values for P2X7 protein expression in the control, 50-, 70-, and 100-ng/d-gp120 groups were 0.88 ± 0.07, 1.41 ± 0.12, 1.28 ± 0.13, and 1.31 ± 0.10, respectively. The above results showed that the expression of P2X7 increased significantly in the hippocampus of gp120 rats compared to that of the control group. These results suggest that ICV infusion of gp120 can successfully mimic HAD in rats, and P2X7 may be involved in gp120-induced cognitive dysfunction. This could provide a theoretical foundation and potential drug target for research and treatment of ADC.

Protective effects of naringin against gp120-induced injury mediated by P2X7 receptors in BV2 microglial cells.

This study was aimed at exploring the effects of P2X7 receptors on gp120-induced injury and naringin's protective effects against gp120-induced injury in BV2 microglia. BV2 microglia injury model was established by gp120 treatment and MTS assay was used to verify whether naringin has a cell-protective effect against gp120-induced injury. Changes in P2X7 receptor expression were assayed using RT-PCR, qPCR, and western blot. Results showed that the ODs of the Ctrl, gp120, gp120+naringin, and gp120+BBG groups were 0.91 ± 0.10, 0.71 ± 0.09, 0.83 ± 0.10, and 0.83 ± 0.10, respectively. Compared to the control group, the gp120 group showed a significantly decreased cell survival rate. Cell survival rates of the gp120+naringin group increased significantly compared to those of the gp120 group, while no difference was observed when compared to the gp120+BBG group. The relative P2X7 mRNA expression levels in the Ctrl, gp120, gp120+naringin, and gp120+BBG groups were 0.73 ± 0.06, 1.05 ± 0.06, 0.78 ± 0.05, and 0.81 ± 0.04, respectively. The corresponding P2X7 protein expression levels were 0.46 ± 0.04, 0.79 ± 0.04, 0.38 ± 0.07, and 0.42 ± 0.06. P2X7 mRNA and protein expression in the gp120 group increased significantly compared to those in the control group, and declined in the gp120+naringin group compared to those in the gp120 group. Therefore, P2X7 receptors might be involved in gp120-induced injury in BV2 microglia, and naringin might play a protective role by inhibiting the up-regulated expression of P2X7 receptors.

Effect of weaning age on cortisol release in piglets.

The effect of weaning age on the adrenal cortex, which plays a vital role in the stress response, is currently unknown. Therefore, plasma adrenocorticotropic hormone (ACTH) and cortisol levels, weights and relative weights of adrenal glands, and steroidogenesis-related protein and enzyme expression levels in piglets weaned on different days were determined. Piglets weaned at 35 days had significantly lower ACTH levels than those weaned at 14 or 21 days, and cortisol levels of piglets weaned at 21, 28, and 35 days were significantly lower than those of piglets weaned on day 14. Adrenal gland weights of piglets weaned at 28 and 35 days and relative adrenal gland weights of piglets weaned at 35 days were significantly lower than those of piglets weaned at 14 days. However, no significant difference was detected in the expression of melanocortin-type 2 receptor mRNA, which is associated with weaning age. Steroidogenic acute-regulatory (StAR) mRNA and cholesterol side-chain cleavage cytochrome P450 mRNA expression levels in piglets weaned at 28 and 35 days were significantly lower than in those weaned at 14 or 21 days, and P450 11ß mRNA expression levels in piglets weaned at 28 and 35 days were significantly lower than in those weaned at 14 days. Therefore, early-weaned piglets exhibited increased adrenal gland weights and StAR and steroidogenic enzyme expression, all of which contributed to high cortisol levels. The high plasma ACTH and cortisol levels in early-weaned piglets indicate that these animals would be greatly affected by stress.

Sequence variation in the Toxoplasma gondii ROP20 gene among strains from different hosts and geographical locations.

Toxoplasma gondii, an opportunistic protozoan parasite, infects almost all warm-blooded animals. In this study, we examined the sequence variation in rhoptry protein 20 (ROP20) genes among 18 T. gondii isolates collected from different hosts and geographical regions. Full length ROP20 genes were amplified and sequenced. The results showed that the genes were 1659 bp in length and contained only a single exon, and that the A+T content varied from 46.68 to 47.20% among the 18 strains. The results of sequence alignment indicated that there were 30 variable nucleotide positions (0-1.40%) in the 18 T. gondii strains containing 18 transitions and 11 transversions, representing 1.81% overall sequence variation. Phylogenetic analysis of the ROP20 sequences showed that ROP20 variation could differentiate between the clonal lineage genotypes I and ToxoDB #9, indicating that ROP20 exhibits a relatively marked degree of sequence diversity and might represent a novel genetic marker for intraspecies phylogenetic analyses of T. gondii.

Ox-LDL increases OX40L in endothelial cells through a LOX-1-dependent mechanism.

Oxidative low-density lipoprotein (Ox-LDL) is a key risk factor for the development of atherosclerosis, and it can stimulate the expression of a variety of inflammatory signals. As a new and highly sensitive inflammation index, OX40L may be a key to understanding the mechanisms that regulate interactions between cells within the vessel wall and inflammatory mediators during the development of atherosclerosis. To investigate whether Ox-LDL regulates OX40L expression through an oxidized LDL-1 receptor (LOX-1)-mediated mechanism, we investigated the effect of different concentrations of Ox-LDL (50, 100, 150 µg/mL) on endothelial cell proliferation and apoptosis. Stimulation with Ox-LDL increased OX40L protein 1.44-fold and mRNA 4.0-fold in endothelial cells, and these effects were inhibited by blocking LOX-1. These results indicate that LOX-1 plays an important role in the chronic inflammatory process in blood vessel walls. Inhibiting LOX-1 may reduce blood vessel inflammation and provide a therapeutic option to limit atherosclerosis progression.

Ox-LDL increases OX40L in endothelial cells through a LOX-1-dependent mechanism

Oxidative low-density lipoprotein (Ox-LDL) is a key risk factor for the development of atherosclerosis, and it can stimulate the expression of a variety of inflammatory signals. As a new and highly sensitive inflammation index, OX40L may be a key to understanding the mechanisms that regulate interactions between cells within the vessel wall and inflammatory mediators during the development of atherosclerosis. To investigate whether Ox-LDL regulates OX40L expression through an oxidized LDL-1 receptor (LOX-1)-mediated mechanism, we investigated the effect of different concentrations of Ox-LDL (50, 100, 150 µg/mL) on endothelial cell proliferation and apoptosis. Stimulation with Ox-LDL increased OX40L protein 1.44-fold and mRNA 4.0-fold in endothelial cells, and these effects were inhibited by blocking LOX-1. These results indicate that LOX-1 plays an important role in the chronic inflammatory process in blood vessel walls. Inhibiting LOX-1 may reduce blood vessel inflammation and provide a therapeutic option to limit atherosclerosis progression.

Plasma nitric oxide levels in newborn infants with sepsis.

Nitric oxide is thought to play an important role in the mediation of the cardiovascular features of septic shock. We determined plasma levels of nitrite and nitrate (not differentiated in measurement) in neonates with sepsis and found these levels to be elevated at the time of entry compared with those of control subjects (p < 0.05); the levels were significantly higher in the patients with sepsis and shock than in those without shock (p < 0.05). Elevations of nitrite plus nitrate were correlated with tumor necrosis factor and severity of illness judged by pediatric risk of mortality (PRISM) scores at onset (p < 0.05). Of 8 newborn infants with a nitrite-plus-nitrate value > 200 mumol/L, 6 had septic shock; none of 12 not reaching that cutoff value had septic shock (p < 0.05). Levels of nitrite plus nitrate were elevated as much in gram-positive as in gram-negative sepsis. We conclude that the determination of circulating plasma levels of nitrite plus nitrate may be useful in forecasting the severity of illness and the occurrence of septic shock; therapeutic approaches associated with inhibition of nitric oxide synthesis may be worth trying in infants with septic shock.