C-jun mRNA Levels Research Articles

Topical metformin accelerates wound healing by promoting collagen synthesis and inhibiting apoptosis in a diabetic wound model.

The wound healing process, which is a pathophysiological process that includes various phases, is interrupted in diabetes due to hyperglycemia, and since deterioration occurs in these phases, a normal healing process is not observed. The aim of the current study is to investigate the proliferative and antiapoptotic effects of metformin on wound healing after topical application on diabetic and non-diabetic wounds. For this purpose, we applied metformin topically on the full-thickness excisional wound model we created in diabetic and nondiabetic groups. We investigated the effects of metformin on the apoptotic index by the Terminal deoxynucleotidyl transferase mediated dUTP Nick-End Labeling method and on collagen-I, collagen-III, p53, and c-jun expression levels by quantitative reverse transcription polymerase chain reaction technique in wound biopsy tissues. Our results showed that c-jun and p53 mRNA levels and apoptotic index increased with the effect of diabetes, while collagen synthesis was disrupted. As a result of the study, we showed that metformin increases cellular proliferation and has anti-apoptotic effects by increasing collagen-I/III expression and decreasing p53/c-jun level, especially in diabetic wounds and also in normal wounds. In conclusion, the topical effect of metformin on diabetic wounds reversed the adverse effects caused by diabetes, increasing the wound healing rate and improving the wound repair process.

The sodium borate relieves the hypertrophic damage induced during pregnancy, it improves contractibility, reduces oxidative stress and stimulates cell proliferation

IntroductionFetal and postnatal hypertrophy develop in response to such different exposures or illnesses the mother suffers during gestation as anti-infectious and physical agents, obesity, hypertension, diabetes, and even advanced maternal age. This gives rise to high comorbidities in the newborn; therefore, looking for alternatives that contribute to cardiac homeostasis is quite necessary to inhibit the overgrowth of myocytes. Boron-derivative compounds could play a key role in exerting a repairing effect on chronic cardiac damage induced during gestation. MethodologyThe cardiotoxic effect of 6.4, 12 and 100 mg/kg of sodium tetraborate administered by oral delivery route to healthy pregnant mice was assessed. After that, the use of the chemical compound was tested in the treatment of pregnant mice previously subjected to isoproterenol (fetal hypertrophy model) on the fifth day post coitus. Prior to the sacrifice of the pups of mice an electrocardiography (ECG) was done. Morphological and histological changes of heart were assessed in newborn pups. As a damage marker, the concentration of p38 nitrogen-activated protein kinases were evaluated by using Western Blot and the levels of malondialdehyde (MDA) as well as glutathione antioxidants (GSH) and glutathione peroxidase (GPx) were tested by spectrometry. Moreover, the mRNA expression for early response genes (c-jun, c-fos y c-myc), late response (GATA-4, Mef2c, NFAT) and heart damage (ANP and BNP) was measured by qPCR real time. ResultsThe supply of 6,4 and 12 mg/kg-sodium tetraborate favored ventricular remodeling with histological alterations. By comparison, 100 mg/kg of sodium tetraborate administered during the fetal stage did not alter neither the cardiac morphology of six-week old pups nor the p38/P-p38MAPK ratio remained the same and no oxidative stress was observed.When pregnant females treated with isoproterenol were treated with 100 mg/kg sodium tetraborate during the fetal stage, an improvement in contractility was detected in the pups with an actual reduction in myocardial fibrosis and oxidative stress, but cardiac mass increased. In addition, the expression levels of c-jun, c-myc, GATA-4, MEF2c and ANP mRNA declined in comparison with CTR. However, the hypertrophic damage mechanism was sustained by c-fos, NFAT and BNP expressions. ConclusionsThe set of results achieved suggests that high concentrations of sodium tetraborate have no cardiotoxic effects. Furthermore, sodium tetraborate mitigates hypertrophy induced during pregnancy, thereby improving contractibility, reducing oxidative stress and stimulating cell proliferation. Therefore, sodium tetraborate could be an excellent prophylactic treatment administered by delivery oral route during pregnancy when there is a risk of developing fetal left ventricular hypertrophy (LVH).

Effect of Doxycycline on Intrinsic Apoptosis of Myeloma Cell Line H929 and Its Mechanism

To investigate the mechanism of the in vitro toxicity of doxycycline to myeloma cell line H929 and also the possible pathway involved its toxicity. Myeloma cell line H929 was treated with DOX, MEK inhibitor U0126 or RAS agonist ML-098, either alone or in combination. Then, the expression of p-MEK, caspase-3, caspase-9 and c-Jun in H929 were used to detected by Western blot; the cells proliferation and apoptosis were detected by CCK-8 assay and flow cytometry, respectively. DOX significantly increased the levels of cleaved caspase-3 and caspase-9, and down-regulated the level of p-MEK in H929 (P<0.05). MEK antagonist U0126 significantly increased the levels of cleaved caspase-3 and caspase-9, and down-regulated the level of p-MEK (P<0.05). After Dox combined with ML-098 treatment of H929 cells, the apoptosis rate of H929 cells was lower than that of DOX alone treatment group(P<0.05). Compared with DOX alone treatment group, the expressions of p-MEK and p-ERK1/2 in DOX+ML-098 combined treatment group were increased, and the levels of cleaved caspase-3,9 in H929 cells were decreased (P<0.05). The levels of c-Jun mRNA and protein increased in H929 when treated by DOX alone (P<0.05). DOX can induce apoptosis of H929 via intrinsic apoptosis pathway, and MEK/ERK pathway and c-Jun possibly play a role in this process.

Stem cells from human exfoliated deciduous teeth relieve pain via downregulation of c-Jun in a rat model of trigeminal neuralgia.

Stem cells from human exfoliated deciduous teeth (SHED) have excellent immunomodulatory and neuroprotective abilities. It is possible that systemic SHED transplantation could ameliorate trigeminal neuralgia. The phosphorylation of c-Jun contributes to the development of hyperalgesia and allodynia. The present study aimed to evaluate whether systemic SHED transplantation could lead to analgesic effects by regulating peripheral c-Jun in the trigeminal ganglia (TG) in a rat model of trigeminal neuralgia. Chronic constriction injury of the infraorbital nerve (CCI-ION) was performed to establish a rat pain model. SHED were obtained from discarded exfoliated deciduous teeth from children and transplanted by a single infusion through the tail vein. SHED were labelled with the PKH26 red fluorescent cell linker mini kit for tract distribution. The mechanical threshold was determined using von Frey filaments. The mRNA levels of c-Jun in the ipsilateral TG were quantified. The phosphorylation of c-Jun in the ipsilateral TG was assessed by immunohistochemistry and Western blotting. PKH26-labelled SHED were distributed to both sides of TG, lung, liver and spleen. Systemic SHED transplantation significantly elevated the mechanical thresholds in CCI-ION rats and blocked the upregulation of c-Jun mRNA levels in the TG caused by nerve ligation. The activation of c-Jun in the TG was blocked by SHED transplantation. These findings demonstrate that systemic SHED administration reverts trigeminal neuralgia via downregulation of c-Jun in the TG.

The Dual Effects of Silibinin on Human Pancreatic Cells

Objective: Silibinin is a flavonoid with antihepatotoxic properties, and exhibits pleiotropic anticancer effects. However, the molecular mechanisms responsible for its anticancer actions in pancreatic cancer cells, and the effects on such cells and normal pancreatic cells, remain unclear. The objective of this study was to determine the effect of silibinin on human pancreatic cancer cells and normal ductal cells. Methods: Human pancreatic cancer cells (MIA PaCa-2 and PANC-1) and normal ductal cells (hTERT-HPNE) were cultured with 0-400 μM silibinin for 48 h. Thereafter, the proliferation, invasion, apoptosis, and signaling pathways of the pancreatic cells were evaluated. Results: Silibinin significantly inhibited the proliferation, invasion, and spheroid formation of human pancreatic cancer cells in vitro in a dosedependent manner (p&lt;0.05). It also induced apoptosis in a dose-dependent manner. Western blot analysis showed that silibinin downregulated extracellular signaling-regulated kinase (ERK) and serine/threonine protein kinase (AKT) in human pancreatic cancer cells. It also upregulated microtubule associated protein 1 light chain 3 β (LC3B) and cleaved caspase-3 via c-Jun N-terminal kinases (JNK) signaling. On the other hand, silibinin increased the mRNA and protein levels of c-Jun, Twist-related protein 1, and Snail. It also decreased exogenous p53 levels, but increased endogenous c-Jun protein levels in human pancreatic cancer cells. However, silibinin did not affect cell viability and endogenous c-Jun levels in pancreatic normal ductal cells. It increased exogenous p53 levels, but decreased stemness-related gene expression in pancreatic normal ductal cells. Silibinin increased Ki-67 levels in pancreatic cancer cells, but decreased them in pancreatic normal ductal cells. Conclusion: Silibinin not only exerted anticancer effects by inhibiting AKTERK and JNK signaling, but also upregulated cancer stemness-related genes in human pancreatic cancer cells. These results suggest that silibinin should be used as a therapeutic agent for human pancreatic cancer with caution.

Methionine- and Choline-Deficient Diet–Induced Nonalcoholic Steatohepatitis Is Associated with Increased Intestinal Inflammation

Inflammation drives the pathogenesis of nonalcoholic steatohepatitis (NASH). The current study examined changes in intestinal inflammation during NASH. In male C57BL/6J mice, feeding a methionine- and choline-deficient diet (MCD) resulted in severe hepatic steatosis and inflammation relative to feeding a chow diet (CD). MCD-fed mice exhibited characteristics of mucosal and submucosal inflammatory responses compared with CD-fed mice. Moreover, intestinal phosphorylation states of c-Jun N-terminal protein kinase p46 and mRNA levels of IL-1B, IL-6, tumor necrosis factor alpha, and monocyte chemoattractant protein-1 were significantly higher and intestinal mRNA levels of IL-4 and IL-13 were significantly lower in MCD-fed mice compared with those in CD mice. Surprisingly, upon treatment with MCD-mimicking media, the proinflammatory responses in cultured intestinal epithelial CMT-93 cells did not differ significantly from those in CMT-93 cells treated with control media. In contrast, in RAW264.7 macrophages, MCD-mimicking media significantly increased the phosphorylation states of c-Jun N-terminal protein kinase p46 and mitogen-activated protein kinases p38 and mRNA levels of IL-1B, IL-6, IL-10, and tumor necrosis factor alpha under either basal or lipopolysaccharide-stimulated conditions. Collectively, these results suggest that increased intestinal inflammation is associated with NASH phenotype. Thus, elevated proinflammatory responses in macrophages likely contribute to, in large part, increased intestinal inflammation in NASH.

Speckle-type POZ protein up-regulates c-Jun protein expression and promotes proliferation and invasion of renal carcinoma cells

To investigate the effect of speckle-type POZ protein (SPOP) on proliferation, apoptosis, migration and invasion of renal cell carcinoma (RCC) and explore the potential mechanisms. Renal carcinoma cell lines (786-O, A704, and Caki-2) cultured in vitro were transfected with a SPOP-overexpressing plasmid, and the changes in proliferation of the cells were detected using colony formation and MTT assay; TUNEL assay was used to assess apoptosis of the cells. The changes in migration and invasion abilities of the cells were examined using wound healing assay and Transwell assay. The mRNA and protein levels of SPOP and c-Jun in the transfected cells were measured using real-time PCR and Western blotting. SPOP over-expression obviously promoted the proliferation, migration and invasion of 786-O, A704 and Caki-2 cells (P < 0.05). Compared with the control cells, 786-o and Caki-2 cells over-expressing SPOP exhibited significantly lowered apoptosis rates (P < 0.05). The results of real-time PCR demonstrated that the transfected cells did not show obvious changes in the mRNA level of c-Jun, but the protein expressions of SPOP and c-jun increased significantly as shown by Western blotting (P < 0.05). SPOP can promote proliferation, migration, and invasion and suppress apoptosis of renal carcinoma cells possibly by promoting the expression of c-Jun.

Effect of pemafibrate (K-877), a novel selective peroxisome proliferator-activated receptor α modular (SPPARMα), in atherosclerosis model using low density lipoprotein receptor knock-out swine with balloon injury.

BackgroundPeroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor that has key roles of lipid metabolism and inflammation. The PPARα may affects the initiation and progression of atherosclerosis by reducing inflammatory responses. Pemafibrate (K-877) is a novel selective PPARα modulator (SPPARMα), which was designed to possess higher PPARα potency and selectivity than existing PPARα agonists. The aim of this study is to evaluate the effect of pemafibrate on vascular response in coronary atherosclerosis model using low density lipoprotein receptor knock-out (LDLR-KO) pigs with balloon injury.Methods and resultsTen LDLR-KO pigs were randomly allocated to two groups [pemafibrate (n = 5) and control (n = 5)] and fed with a diet containing 2.0% cholesterol and 20% lard throughout the study. Balloon injury was created in 40 coronary segments two weeks after starting the oral administration of pemafibrate or placebo. Necropsy was conducted 8 weeks later. Coronary artery sections were reviewed to evaluate lesion progression and the mRNA expression levels for C-Jun, NFκ B, CCL2, CCR7, CD163 and MMP9 determined using real-time RT-PCR. LDL cholesterol at baseline was about 700 mg/dL. The mean ratio of macrophages to plaque area was significantly lower in pemafibrate group compared with control one (7.63±1.16 vs 14.04±4.51, P = 0.02) whereas no differences were observed in intimal area between groups. The mRNA levels of C-Jun, NFκB and MMP9 were significantly decreased in pemafibrate group.ConclusionsPemafibrate was associated with inhibition of inflammatory responses in coronary artery atherosclerosis model using LDLR-KO swine with balloon injury.

Increased O-GlcNAcylation induces myocardial hypertrophy.

Myocardial hypertrophy is a common precursor of many diseases, and it can lead to myocardial ischemia and weaken cardiac contractility. High-sugar diets and diabetes are high risk factors for cardiac hypertrophy. O-GlcNAcylation, a dynamic and ubiquitous post-translational glycosylation of proteins on serine/threonine residues, has been usually considered as a nutrient sensor. Hyperglycemia, hyperlipidemia, and hyperinsulinemia lead to an enhancement of protein O-GlcNAcylation; however, whether excessive O-linked β-N-acetylglucosamine (O-GlcNAc) glycosylation of proteins in cardiomyocytes causes cardiac hypertrophy remains unclear. In this study, we treated cultured primary cardiomyocytes or mice with streptozotocin (STZ) or PUGNAc, two inhibitors of O-GlcNAcase (OGA) to elevate cellular O-GlcNAcylation. We found that increased O-GlcNAcylation induced hypertrophy-like changes by detecting cardiomyocyte morphology or measuring the thickness of mice left ventricular wall with HE staining. The mRNA levels of cardiac hypertrophy-related genes, atrial natriuretic peptide (ANP) and β-myosin heavy chain (β-MHC), are increased in drug treatment groups. We further found that the increase of O-GlcNAcylation upregulated the activity of cAMP response element-binding protein (CREB) in cultured primary cells and in vivo by detecting the phosphorylation level of CREB by Western blot and the mRNA levels of CREB downstream targets C-fos and C-jun by RT-qPCR. These results suggest that the increased O-GlcNAcylation in cardiomyocytes is associated with cardiac hypertrophy both in cultured cells and in vivo, which provides possible intervention targets and approaches for the clinical treatment of myocardial hypertrophy triggered by high carbohydrate diets.

KDM5c Promotes Colon Cancer Cell Proliferation Through the FBXW7-c-Jun Regulatory Axis.

KDM5c is a histone demethylase that specifically demethylates trimethylated and dimethylated H3 Lys-4 to play a central role in transcriptional repression. C-Jun is a proto-oncogene and promotes cell proliferation when ectopically accumulated, but can be ubiquitinated by SCF (FBXW7), leading to its degradation. FBXW7 is an E3 ubiquitin ligase of c-Jun, and exhibits carcinostasis in colon cancer. Here, we report that overexpression of KDM5c in human colon cancer cells results in attenuated FBXW7 transcription and accumulated c-Jun protein, leading to increased proliferation of colon cancer cells. We show that overexpression of KDM5c can result in increased c-Jun protein levels and decreased ubiquitin levels, with no significant change in mRNA levels of c-Jun. KDM5c overexpression blocks the ubiquitin-proteasome proteolytic pathway of c-Jun by down-regulating the expression of FBXW7. KDM5c down-regulation of FBXW7 occurs by demethylation of H3K4me3 at TSS and downstream of the FBXW7 gene. And interaction of KDM5c with H3K4me3 downstream of FBXW7 gene may be followed by recruitment of DNMT3b to methylate the spatially close CpG island located near the FBXW7 TSS. This methylation represses FBXW7 gene expression, which can reduce c-Jun degradation via the ubiquitin-proteasome pathway. TCGA database analysis revealed high expression of KDM5c in colon cancer tissues. KDM5c expression in colon cancer was correlated with poor overall survival of patients in the first 7 years. Data from TCGA showed that high expression of KDM5c was correlated with high DNA methylation of the FBXW7 gene, but was not positively correlated with methylation of the Jun gene. These results suggest that KDM5c regulation of colon cell proliferation is mainly mediated by the KDM5c-FBXW7-c-Jun axis.

Concentrated growth factor inhibits UVA-induced photoaging in human dermal fibroblasts via the MAPK/AP-1 pathway.

Ultraviolet (UV) radiation-induced photoaging is one of the contributors to skin aging. UV light triggers oxidative stress, producing a large number of matrix metalloproteinases (MMPs) and degrading the extracellular matrix in skin cells, thereby causing a series of photoaging symptoms. Concentrated growth factor (CGF) is a leukocyte- and platelet-rich fibrin biomaterial that plays a protective role in the occurrence and development of skin photoaging. In the present study, we investigated the underlying mechanism of CGF in the UVA-induced photoaging of human dermal fibroblasts (HDFs). A primary culture of HDFs was isolated from normal human facial skin. The cells were treated with CGF following UVA radiation. Proliferation of cells was detected using MTT assay, followed by measurement of reactive oxygen species (ROS) using immunofluorescence assay and flow cytometry. The mRNA and protein expression levels of P38, c-Jun, and MMP-1 were detected using real-time polymerase chain reaction and Western blot, respectively. CGF was found to improve cell viability by inhibiting the production of ROS and reducing oxidative damage. In addition, there was lower expression of p38 and c-Jun at the mRNA and protein levels following CGF treatment, thus resulting in the inhibition of MMP-1 expression. Our results suggest that CGF could protect HDFs against UVA-induced photoaging by blocking the P38 mitogen-activated protein kinase/activated protein-1 (P38MAPK/AP-1) signaling pathway. These findings provide a new clinical strategy for the prevention of skin photoaging.

Screening of molecular markers of induced chemotherapy in supraglottic laryngeal squamouscell carcinoma.

ObjectiveTo investigate the expressions of MAPK10, c-Jun and Itga6 in laryngeal carcinoma and its influence on the sensitivity to docetaxel, cisplatin and 5-fluorouracil (TPF) chemotherapy.MethodsFifty-seven patients with supraglottic squamous cell carcinoma, who were treated by two cycles of TPF induction chemotherapy in our hospital, were enrolled in this study and divided into groups by chemotherapy resistance or chemotherapy sensitivity. The expressions of mRNA and protein of MAPK10, c-Jun and Itga6 in tumor tissues were evaluated by immunohistochemistry. The consistency of mRNA and protein expressions was tested, and the relation with the clinicopathological features was analyzed.ResultsThe positive rates of MAPK10 andc-Jun in the tumor tissues of the sensitive group were significantly higher than those of there assistant group, which was 90.48% and 100.00%, respectively. The expression rate of Itga6 was significantly higher in the resistant group, which was 83.33% (P < 0.05). The mRNA levels of MAPK10 and c-Jun were significantly lower in the resistant group than in the sensitive group, whilethemRNA levelof Itga6was significantly higher in the resistant group (P < 0.05). The protein expressions of MAPK10, c-Jun and Itga6 were consistent with their mRNA expressions (P < 0.05). The expressions of MAPK10, c-Jun and Itga6 were not correlatedwithage, gender and tumor diameter (P > 0.05). However, the expressions of MAPK10 and c-Jun were negatively correlated withclinical stage and pathological grading (P < 0.05). Negative correlations between MAPK 10 and Itga6, and between c-Jun and Itga6in tumor tissues were found by Spearman'srank correlation coefficient (P < 0.05). The correlation was also negative in the resistant tumor tissues (P < 0.05).ConclusionThe MAPK10 and c-Jun expressions were down-regulated, while the Itga6 expression was up-regulated in the chemo-resistant laryngeal carcinoma, and the expression levels of different factors were correlated witheach other. These factorsmight be important biomarkers for predicting outcomes of TPF chemotherapy in laryngeal carcinoma in the future.

Yiqi Huoxue Recipe Improves Liver Regeneration in Rats after Partial Hepatectomy via JNK Pathway.

The liver is the only visceral organ that exhibits a remarkable capability of regenerating in response to partial hepatectomy (PH) or chemical injury. Improving liver regeneration (LR) ability is the basis for the favourable treatment outcome of patients after PH, which can serve as a potential indicator for postoperative survival. The present study aimed to investigate the protective effects of Yiqi Huoxue recipe (YQHX) on LR after PH in rats and further elucidate its underlying mechanism. A two-thirds PH rat model was used in this study. Wistar rats were randomly divided into four groups: sham-operated, PH, YQHX + PH, and Fuzheng Huayu decoction (FZHY) + PH groups. All rats were sacrificed under anesthesia at 24 and 72 h after surgery. The rates of LR were calculated, and the expression levels of cyclin D1 and c-jun were determined by immunohistochemical staining. The protein levels of p-JNK1/2, JNK1/2, p-c-jun, c-jun, Bax, and Bcl-2 were detected by Western blotting, while the mRNA levels of JNK1, JNK2, c-jun, Bax, and Bcl-2 were examined by real-time polymerase chain reaction (RT-PCR). At the corresponding time points, YQHX and FZHY administration dramatically induced the protein levels of p-JNK1/2 compared to the PH group (p < 0.05), while FZHY + PH group showed prominently increase in p-JNK1/2 protein levels compared to the YQHX + PH group (p < 0.05). A similar trend was observed for the expression levels of p-c-jun. Compared to the PH group, YQHX and FZHY markedly reduced the mRNA and protein expression levels of Bax at 24 h after PH, while those in the FZHY + PH group decreased more obviously (p < 0.05). Besides, in comparison with the PH group, YQHX and FZHY administration predominantly upregulated the mRNA and protein expression levels of Bcl-2 at 24 and 72 h after PH (p < 0.05). In conclusion, YQHX improves LR in rats after PH by inhibiting hepatocyte apoptosis via the JNK signaling pathway.

Resveratrol attenuates diabetes-associated cell centrosome amplification via inhibiting the PKCα-p38 to c-myc/c-jun pathway.

Type 2 diabetes increases the risk for cancer. Centrosome amplification can initiate tumorigenesis. We have described that type 2 diabetes increases the centrosome amplification of peripheral blood mononuclear cells, with high glucose, insulin, and palmitic acid as the triggers, which suggests that centrosome amplification is a candidate biological mechanism linking diabetes to cancer. In this study, we aimed to further investigate the signaling pathways of the diabetes-associated centrosome amplification and to examine whether and how resveratrol inhibits the centrosome amplification. The results showed that treatment with high glucose, insulin, and palmitic acid, alone or in combination, could increase the protein levels of phospho-protein kinase C alpha (p-PKCα), phospho-p38 mitogen-activated protein kinases (p-p38), c-myc, and c-jun, as well as the mRNA levels of c-myc and c-jun. PKCα inhibitor could inhibit the treatment-induced increase in the protein levels of p-p38, c-myc, and c-jun. Inhibitor or siRNA of p38 was also able to inhibit the treatment-induced increase in the levels of p-p38, c-myc, and c-jun. Meanwhile, knockdown of c-myc or c-jun did not alter the treatment-induced increase in the phosphorylation of PKCα or p38. Importantly, inhibition of the phosphorylation of PKCα or p38 and knockdown of c-myc or c-jun could attenuate the centrosome amplification. In diabetic mice, the levels of p-PKCα, p-p38, c-myc, and c-jun were all increased in the colon tissues. Interestingly, resveratrol, but not metformin, was able to attenuate the treatment-induced increase in the levels of p-PKCα, p-p38, c-myc, and c-jun, as well as the centrosome amplification. In conclusion, our results suggest that PKCα-p38 to c-myc/c-jun is the signaling pathway of the diabetes-associated centrosome amplification, and resveratrol attenuates the centrosome amplification by inhibiting this signaling pathway.

Man-made mineral fiber effects on the expression of anti-oncogenes P53 and P16 and oncogenes C-JUN and C-FOS in the lung tissue of Wistar rats

Man-made mineral fibers (MMMFs) are substitutes for asbestos. MMMFs are widely used as insulation, but their molecular mechanisms underlying the tumorigenic effects in vivo have been poorly studied. For this reason, this work aimed to explore the properties and carcinogenic molecular mechanisms of MMMFs. The three MMMFs, rock wool (RW), glass fibers (GFs), and ceramic fibers (CFs), were prepared into respirable dust. Particle size, morphology, and chemical composition were analyzed by laser particle analyzer, scanning electron microscope, and X-ray fluorescence spectrometer, respectively. The Wistar rats were administered multiple intratracheal instillations of three MMMFs once a month. Then, several parameters (e.g. body mass, lung mass, and lung histology) were measured at 1, 3, and 6 months. After that, levels of P53, P16, C-JUN, and C-FOS mRNA and protein were measured by quantitative real-time reverse transcription polymerase chain reaction and Western blotting. This work found that exposure to MMMFs could influence the growth of body mass and increase lung mass. General conditions showed white nodules and irregular atrophy. In addition, MMMFs could lead to inactivation of anti-oncogene P16 and activation of proto-oncogenes (C-JUN and C-FOS) in the mRNA and protein levels, in which GF and CF were more obvious compared with RW. The effect of MMMFs was different, which may be related to the physical and chemical characteristics of different MMMFs. In conclusion, MMMFs (GF and CF) could induce an unbalanced expression of cancer-related genes in the lung tissues of rats. The understanding of the determinants of toxicity and carcinogenicity provides a scientific basis for developing and introducing new safer MMMF products, and the present study provides some useful insights into the carcinogenic mechanism of MMMFs.

Mechanism of isoniazid-induced hepatotoxicity in zebrafish larvae: Activation of ROS-mediated ERS, apoptosis and the Nrf2 pathway

Isoniazid (INH) is a first-line anti-tuberculosis drug. INH has been detected in surface waters which may create a risk to aquatic organisms. In this study, the hepatotoxicity of INH was elucidated using zebrafish. The liver morphology, transaminase level, redox-related enzyme activity, reactive oxygen species (ROS) content and mRNA levels of liver injury-related genes were measured. The results showed that INH (4, 6 mM) significantly caused liver atrophy and increased levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in zebrafish. INH (6 mM) led to decreased catalase (CAT) activity, glutathione peroxidase (GPx) activity and glutathione (GSH) content but increased ROS and malondialdehyde (MDA) levels. Moreover, INH (6 mM) decreased expression levels of miR-122 and pparα but increased mRNA levels of ap-1 and c-jun. Furthermore, mRNA levels of factors related to endoplasmic reticulum stress (ERS) (grp78, atf6, perk, ire1, xbp1s and chop), apoptosis (bax, cyt, caspase-3, caspase-8 and caspase-9) and the Nrf2 signalling pathway (nrf2, ho-1, nqo1, gclm and gclc) were significantly upregulated. INH may act on hepatotoxicity in zebrafish by increasing ROS content, which weakens the antioxidant capacity, leading to ERS, cell apoptosis and liver injury. In addition, the Nrf2 signalling pathway is activated as a stress compensation mechanism during INH-induced liver injury, but it is not sufficient to counteract INH-induced hepatotoxicity.

Evidences for involvement of estrogen receptor induced ERK1/2 activation in ovarian cancer cell proliferation by Cadmium Chloride

Cadmium (Cd) as a human carcinogen and one of the most toxic industrial and environmental pollutant mimics the estrogenic effects in cell proliferation. So, it might have a role in the incidence and etiology of hormone-related cancers such as ovarian cancer as the most lethal gynecologic malignancy. This study aimed to evaluate the estrogenic effect and underlying mechanism of Cd in ovarian cancer cell line proliferation. OVCAR3 and SKOV3 cell lines were treated with different concentrations of CdCl2 (0- 50 μM). Cell proliferation was analyzed using MTT and BrdU assay. To evaluate the estrogenic effect of Cd, the cells were pre-incubated with estrogen receptor (ER) antagonist ICI 182,780. The expression of ER was determined using western blotting method. Real-time RT-PCR method was used to assess c-fos, c-jun and FOXO3a mRNA level. The results showed that Cd has an estrogenic proliferative effect at nM concentration range and ICI 182,780 significantly reversed the CdCl2-induced cell proliferation. Cd also increased the expression of ERs. Cd exposure induced activation of p-ERK1/2 in these cells. Cd also intensified c-jun, c-fos, and FOXO3a mRNA expression. Taken together, the current work suggests that Cd induces ovarian cancer cell proliferation in an ER-dependent mechanism induced ERK1/2 activation pathway. Understanding of downstream targets by which Cd deregulates cell proliferation can be noteworthy to define its underlying carcinogenesis mechanism.

Secalonic acid D induces cell apoptosis in both sensitive and ABCG2-overexpressing multidrug resistant cancer cells through upregulating c-Jun expression

Secalonic acid D (SAD) could inhibit cell growth in not only sensitive cells but also multidrug resistant (MDR) cells. However, the molecular mechanisms need to be elucidated. Here, we identified that SAD possessed potent cytotoxicity in 3 pairs of MDR and their parental sensitive cells including S1-MI-80 and S1, H460/MX20 and H460, MCF-7/ADR and MCF-7 cells. Furthermore, SAD induced cell G2/M phase arrest via the downregulation of cyclin B1 and the increase of CDC2 phosphorylation. Importantly, JNK pathway upregulated the expression of c-Jun in protein level and increased c-Jun phosphorylation induced by SAD, which was linked to cell apoptosis via c-Jun/Src/STAT3 pathway. To investigate the mechanisms of upregulation of c-Jun protein by SAD, the mRNA expression level and degradation of c-Jun were examined. We found that SAD did not alter the mRNA level of c-Jun but inhibited its proteasome-dependent degradation. Taken together, these results implicate that SAD induces cancer cell death through c-Jun/Src/STAT3 signaling axis by inhibiting the proteasome-dependent degradation of c-Jun in both sensitive cells and ATP-binding cassette transporter sub-family G member 2 (ABCG2)-mediated MDR cells.

Chronic exposure to the ionic liquid [C8mim]Br induces inflammation in silver carp spleen: Involvement of oxidative stress-mediated p38MAPK/NF-κB signalling and microRNAs

The present study aimed to determine the chronic toxicity of 1-methyl-3-octylimidazolium bromide ([C8mim]Br) on the silver carp to further reveal the toxicological mechanisms of ionic liquids. Chronic exposure of silver carp to [C8mim]Br at concentrations of 1.095 and 4.380 mg/L for 60 d was conducted under laboratory conditions. The results revealed that chronic exposure to [C8mim]Br inhibited the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) and reduced glutathione (GSH) levels while markedly increasing malondialdehyde (MDA) and protein carbonyl (PC) levels in fish spleen, indicating that [C8mim]Br treatment induced oxidative stress. Additionally, long-term exposure to [C8mim]Br markedly upregulated the expressions of nuclear factor-κB (NF-κB), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), IL-6, tumour necrosis factor-α (TNF-α), and interferon-γ (IFN-γ); altered the levels of transforming growth factor-β (TGF-β); and increased the mRNA levels of p38MAPK, c-fos, c-jun, and c-myc, suggesting that long-term exposure to [C8mim]Br might promote the inflammatory response in fish spleen and that p38MAPK/NF-κB signalling may potentially be involved in this process. Moreover, [C8mim]Br-exposure altered lysozyme activity and complement 3 (C3) and immunoglobulin M (IgM) content, indicating that chronic [C8mim]Br exposure also has immunotoxic effects on silver carp. Furthermore, we also found that [C8mim]Br exposure reduced miR-125b levels, altered miR-143 levels, and upregulated miR-155 and miR-21 levels, suggesting that these miRNAs may be involved in the [C8mim]Br-induced inflammatory response in fish spleen. In summary, the present study indicates that chronic exposure to [C8mim]Br induces inflammation in fish spleen and that oxidative stress-mediated p38MAPK/NF-κB signalling and miRNAs may play a key role in this process.

Effect of 650-nm low-level laser irradiation on c-Jun, c-Fos, ICAM-1, and CCL2 expression in experimental periodontitis

This study was designed to investigate the effect of 650-nm low-level laser irradiation (LLLI) as an adjunctive treatment of experimental periodontitis. To investigate possible LLLI-mediated anti-inflammatory effects, we utilized an experimental periodontitis (EP) rat model and analyzed c-Jun, c-Fos, ICAM-1, and CCL2 gene expressions on PB leukocytes and in the gingival tissue. Total RNA was isolated from the gingivae and peripheral blood (PB) leukocytes of normal, EP, scaling, and root planing (SRP)-treated EP and LLLI + SRP-treated EP rats, and gene expressions were analyzed by real-time PCR. The productions of c-Jun, c-Fos, ICAM-1, and CCL2 in gingivae were analyzed immunohistochemically. Tartrate-resistant acid phosphatase (TRAP) staining was used to determine osteoclast activity in alveolar bone. The c-Jun and ICAM-1 messenger RNA (mRNA) levels were significantly decreased in the EP rat gingival tissue treated by SRP + LLLI than by SRP, the c-Jun, ICAM-1, and c-Fos mRNA levels on PB leukocytes reduced after LLLI treatment but did not show any significant differences in both groups. There was no significant difference in CCL2 mRNA levels on PB leukocytes and in gingivae between the SRP + LLLI and the SRP groups. The c-Fos mRNA levels in gingivae did not show significant difference in both groups. Immunohistochemistry showed that the CCL2, ICAM-1, c-Jun, and c-Fos productions were significantly reduced in rats of the SRP + LLLI group compared with the only SRP group. LLLI significantly decreased the number of osteoclasts as demonstrated by TRAP staining. The 650-nm LLLI might be a useful treatment modality for periodontitis.