JNK mRNA Expression Research Articles

Vitamin D alleviation of oxidative stress in human retinal pigment epithelial cells.

Oxidative stress-induced retinal pigment epithelium (RPE) cell damage is a major factor in age-related macular degeneration (AMD). Vitamin D3 (VD3) is a powerful antioxidant and it has been suggested to have anti-aging properties and potential for treating AMD. This study aimed to investigate the effect of VD3 on RPE cell oxidative apoptosis of RPE cells in order to provide experimental evidence for the treatment of AMD. Human retinal pigment epithelial cell 19 (ARPE-19) cells were divided into four groups: blank group (untreated), model group (incubated in medium with 400μmol/L H2O2 for 1h), VD3 group (incubated in medium with 100μmol/L VD3 for 24h), and treatment group (incubated in medium with 400μmol/L H2O2 for 1h and 100μmol/L VD3 for 24h). Cell viability, cell senescence, ROS content, expression levels of vitamin D specific receptors, Akt, Sirt1, NAMPT, and JNK mRNA expression levels, SOD activity, and MDA, GSH, and GPX levels were measured. We first established an ARPE-19 cell stress model with H2O2. Our control experiment showed that VD3 treatment had no significant effect on ARPE-19 cell viability within 6-48h. Treating the stressed ARPE-19 cells with VD3 showed mixed results; caspase-3 expression was decreased, Bcl-2 expression was increased, MDA level of ARPE-19 cells was decreased, GSH-PX, GPX and SOD levels were increased, the relative mRNA expression levels of Akt, Sirt1, NAMPT were increased (P < 0.05), and the relative mRNA expression level of JNK was decreased (P < 0.05). VD3 can potentially slow the development of AMD.

Acteoside promotes autophagy and apoptosis of hepatoma cells by regulating JNK signaling pathway

This study explored the molecular mechanism of acteoside against hepatoma 22(H22) tumor in mice through c-Jun N-terminal kinase(JNK) signaling pathway. H22 cells were subcutaneously inoculated in 50 male BALB/c mice, and then the model mice were classified into model group, low-dose, medium-dose, and high-dose acteoside groups, and cisplatin group. The administration lasted 2 weeks for each group(5 consecutive days/week). The general conditions of mice in each group, such as mental status, diet intake, water intake, activity, and fur were observed. The body weight, tumor volume, tumor weight, and tumor-inhibiting rate were compared before and after administration. Morphological changes of liver cancer tissues were observed based on hematoxylin and eosin(HE) staining, and the expression of phosphorylated(p)-JNK, JNK, B-cell lymphoma-2(Bcl-2), Beclin-1, and light chain 3(LC3) in each tissue was detected by immunohistochemistry and Western blot. qRT-PCR was performed to detect the mRNA expression of JNK, Bcl-2, Beclin-1, and LC3. The general conditions of mice in model and low-dose acteoside groups were poor, while the general conditions of mice in the remaining three groups were improved. The body weight of mice in medium-dose acteoside group, high-dose acteoside group, and cisplatin group was smaller than that in model group(P&lt;0.01). The tumor volume in model group was insignificantly different from that in low-dose acteoside group, and the volume in cisplatin group showed no significant difference from that in high-dose acteoside group. Tumor volume and weight in medium-dose and high-dose acteoside groups and cisplatin group were lower than those in the model group(P&lt;0.001). The tumor-inhibiting rates were 10.72%, 40.32%, 53.79%, and 56.44% in the low-dose, medium-dose, and high-dose acteoside groups and cisplatin group, respectively. HE staining showed gradual decrease in the count of hepatoma cells and increasing sign of cell necrosis in the acteoside and cisplatin groups, and the necrosis was particularly obvious in the high-dose acteoside group and cisplatin group. Immunohistochemical results suggested that the expression of Beclin-1, LC3, p-JNK, and JNK was up-regulated in acteoside and cisplatin groups(P&lt;0.05). The results of immunohistochemistry, Western blot, and qRT-PCR indicated that the expression of Bcl-2 was down-regulated in the medium-dose and high-dose acteoside groups and cisplatin group(P&lt;0.01). Western blot showed that the expression of Beclin-1, LC3, and p-JNK was up-regulated in acteoside and cisplatin groups(P&lt;0.01), and there was no difference in the expression of JNK among groups. qRT-PCR results showed that the levels of Beclin-1 and LC3 mRNA were up-regulated in the acteoside and cisplatin groups(P&lt;0.05), and the level of JNK mRNA was up-regulated in medium-dose and high-dose acteoside groups and cisplatin group(P&lt;0.001). Acteoside promotes apoptosis and autophagy of H22 cells in mice hepatoma cells by up-regulating the JNK signaling pathway, thus inhibiting tumor growth.

Effect of acupuncture at "Zhibian" (BL 54) through "Shuidao" (ST 28) on the expression of apoptosis-related factors in rats with premature ovarian insufficiency based on oxidative stress

To explore the possible mechanism of acupuncture at "Zhibian" (BL 54) through "Shuidao" (ST 28) on premature ovarian insufficiency (POI) from the perspective of oxidative stress. Sixty female SD rats were randomly divided into a blank group, a model group, a sham acupuncture group, a medication group, and an acupuncture group, 12 rats in each group. Except the blank group, the rats in the remaining groups were intraperitoneally injected with cyclophosphamide to establish the POI model. After the model was successfully established, the rats in the acupuncture group were treated with acupuncture at "Zhibian" (BL 54) through "Shuidao" (ST 28), with a depth of about 12 mm, and the needle was retained for 30 min; the acupuncture was given once a day, for a total of 4 weeks. The rats in the sham acupuncture group were treated with blunt-head needle to tap the skin surface of "Zhibian" (BL 54), without penetrating the skin, once a day for 4 weeks. The rats in the medication group were treated with estradiol valerate by gastric gavage for 4 weeks. After the intervention, the level of reactive oxygen species (ROS) in the ovarian tissue was detected by fluorescence probe; the expression of c-Jun N-terminal kinase (JNK), forkhead box O1 (FoxO1), tumor suppressor gene protein 53 (p53) and p53 up-regulated modulator of apoptosis (Puma) mRNA and protein in ovarian tissue were detected by real-time fluorescence quantitative PCR and Western blot. Compared with the blank group, the level of ROS and the expression of JNK mRNA, p-JNK protein, FoxO1, p53, Puma mRNA and protein in the ovarian tissue in the model group were increased (P<0.01). Compared with the model group, the level of ROS and the expression of p-JNK protein, FoxO1, p53, Puma mRNA and protein in the ovarian tissue in the sham acupuncture group were slightly reduced, but the difference was not statistically significant (P>0.05). The level of ROS and the expression of JNK mRNA, p-JNK protein, FoxO1, p53, Puma mRNA and protein in the ovarian tissue in the acupuncture group and the medication group were reduced (P<0.01). Acupuncture at "Zhibian" (BL 54) through "Shuidao" (ST 28) could improve the level of oxidative stress, down-regulate the expression of apoptosis-related factors JNK, FoxO1, p53 and Puma induced by oxidative stress, and inhibit the premature failure of ovarian reserve function caused by apoptosis of ovarian granulosa cells in POI rats.

Modified Erchen decoction ameliorates cognitive dysfunction in vascular dementia rats via inhibiting JAK2/STAT3 and JNK/BAX signaling pathways

BackgroundVascular dementia (VaD) is one of the most common clinical syndromes of progressive neurocognitive dysfunction with uncertain mechanisms. Modified Erchen decoction (MECD), developed from “Erchen decoction (ECD)” recorded in “Taiping Huimin Heji Jufang”, showed a good effect in the treatment of VaD. However, its therapeutic mechanism is still unclear. PurposeThis study aimed to elucidate the multi-target mechanisms of MECD against VaD in vivo and in vitro. MethodsVaD model was established by two-vessel obstruction (2-VO) in Sprague-Dawley rats. Six groups, including the control, 2-VO operation, MECD treatment (2.5, 5.0 and 10.0 g kg−1 d−1), donepezil hydrochloride (positive control, 0.45 g kg−1 d−1) were designed in the whole experiment. After oral administration for 4 weeks, the effects of MECD were verified by behavioral experiments, histological observation, and biochemical index analysis. The chemical profiling of MECD was performed by UHPLC-Orbitrap Fusion-HRMS, and a "compound-target-pathway" multivariate network was constructed to validate and elucidate its pharmacological mechanisms. ResultsCompared with 2-VO group, MECD treatment significantly alleviated anxiety and improved spatial memory in VaD rats according to the open field test (OFT) and Y-maze test. A significant increase in neuron number was observed from hematoxylin and eosin (H&E) stained images in cornu ammonis 1 (CA1) of the hippocampal region after MECD treatment. On the one hand, MECD reduced the plasma levels of triglyceride (TG), low-density lipoprotein (LDL), malondialdehyde (MDA), and amyloid-beta 42 (Aβ42), and inhibited mRNA expression of interleukin-1 beta (Il-1β) and Il-6 in the hippocampus. On the other hand, superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were significantly increased after treatment with MECD. Moreover, MECD reduced the mRNA expression and protein expression of janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3), c-Jun N-terminal kinase (JNK), and BCL2-associated X (BAX) in the brain of 2-VO rats. Furthermore, 71 compounds were identified from the extract of MECD. Among them, liquiritin and isochlorogenic acid C gave inhibiting effects on the mRNA expression of Jnk. In addition, liquiritin and hesperetin were conformed with the inhibition of Jak2 transcription level in vitro experiments. ConclusionMECD has demonstrated a significant amelioration effect on cognitive dysfunction in VaD rats via JAK2/STAT3 and JNK/BAX signaling pathways, which represents an innovative insight into the “activate blood and eliminate phlegm” theory.

Butyrate Glycerides Protect against Intestinal Inflammation and Barrier Dysfunction in Mice.

This study investigates the attenuating effects of butyrate glycerides (BG) on intestinal inflammatory responses and barrier dysfunction induced by LPS stimulation. An initial dose-response test was carried out to identify the optimal dose of BG for further testing. The mice were given intragastric administration of BG at different doses followed by lipopolysaccharide (LPS) intraperitoneal injection. The small intestinal morphology and cytokine mRNA expression were measured. With 1.5 g/kg BW BG administration, it was possible to alleviate the injury of duodenal morphology, attenuate ileum villus height reduction and promote IL-10 mRNA expression. Therefore, the optimal dosage of 1.5 g/kg BW BG was selected for the main experiment. The ultrastructure image of jejunum and ileum epithelial cells, mRNA expression, the level of cytokine and immunofluorescence in the ileum were analyzed. The results showed that BG maintain the ileac brush border, tight junction structures and protein expression. BG attenuated the increased inflammatory cytokines, TLR4 and JNK mRNA expression. Taken together, 1.5 g/kg BW BG administration maintained intestinal barrier function and reduced intestinal and body inflammation responses induced by LPS in mice. The mechanism by which BG alleviated intestinal inflammatory response and maintained intestinal barrier function may be related to the JNK signaling pathway.

Anthocyanin from purple sweet potato attenuates lead-induced reproductive toxicity mediated by JNK signaling pathway in male mice

The present work aimed to explore the protective effect of APSP on Pb-induced reproductive toxicity and possible mechanism. APSP (100 mg/kg) was administered to Pb-intoxicated (0.2% lead acetate) male Kunming mice once daily by oral gavage for 6 weeks. Our results showed that APSP exerted male reproductive protection effects as showed by attenuated Pb-induced testicular injury, improved sperm count and motility, and reduced sperm abnormality rate. APSP also restored Pb-induced decrease in both enzymatic and non-enzymatic antioxidants, and GSH/GSSG ratio, but inhibited lipid peroxidation in serum and testes. Moreover, APSP downregulated Pb-induced Bax mRNA and protein expressions, suppressed activation of caspase-3, upregulated Bcl-2 protein expression, and prevented Pb-induced DNA damage. APSP treatment also interfered with Pb-induced testicular JNK signaling through inhibition of JNK mRNA expression and phosphorylation, resulting in inhibition of c-Jun expression. These effects of APSP were abolished by Pb. In conclusion, APSP represents a potential therapeutic agent for preventing Pb-caused reproductive toxicity, which is attributed to its antioxidant and anti-apoptotic properties, as well as, modulation of JNK signaling pathway.

Ginkgolide K potentiates the protective effect of ketamine against intestinal ischemia/reperfusion injury by modulating NF-κB/ERK/JNK signaling pathway

Purpose: To investigate the effect of ginkgolide K and ketamine treatments, alone and in combination, on intestinal ischemia/reperfusion injury (I/R)-induced injury in rats, as well as the mechanism involved.&#x0D; Methods: Rats were treated with ginkgolide K (GK, 15 mg/kg i.v) and ketamine (KTM, 100 mg/kg i.p.), either alone or in combination 30 min before the induction of intestinal I/R. The effects of GK and KTM were determined by assessing the levels of cytokines in serum, and parameters of oxidative stress and ROS production in the intestinal tissues of I/R rats. Moreover, intestinal mRNA expressions of JNK, ERK, p38 and NF-kB were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR).&#x0D; Results: GK and KTM treatments, alone and in combination, reduced cytokine levels in serum and oxidative stress parameters in intestinal tissues, when compared to I/R group of rats. Treatments with GK and KTM, alone and in combination, mitigated the altered mRNA expressions of JNK, ERK, p38 and NF-kB in intestinal tissues of I/R-injured rats.&#x0D; Conclusion: These results reveal that GK potentiates the protective effect of KTM100 on I/R-induced intestinal injury in rats by regulating the NF-kB/ERK/JNK signaling pathway. Therefore, GK and KTM may find use in the management of I/R&#x0D; Keywords: Ginkgolide K, Ketamine, Intestinal injury, Ischemia/Reperfusion, Inflammation

C-Jun NH2-terminal kinase suppression significantly inhibits the growth of transplanted breast tumors in mice

ObjectiveThe current study investigated the effect of c-Jun NH2-terminal kinase (JNK) expression on the growth of transplanted breast cancer tumors in mice.MethodsA breast cancer transplantation model was established in BALB/c mice, which were then treated with SP600125 (30 mg/kg) for 24 days. After sacrificing the mice, the inhibitory effects of SP600125 on breast cancer growth were calculated by weighing tumors. Moreover, vascular endothelial growth factor (VEGF) expression and the tumor microvascular density (MVD) were evaluated via immunohistochemistry. Cell apoptosis was also examined using a TUNEL kit.ResultsCompared with the findings in the control group, SP600125 treatment (30 mg/kg) obviously suppressed tumor growth during the 15-day observation period. SP600125 treatment markedly inhibited JNK mRNA expression. Furthermore, VEGF protein expression (50% vs. 100%) and MVD (18.27 ± 1.70 vs. 23.17 ± 4.02) were also significantly decreased by SP600125 treatment, whereas the apoptosis index was significantly higher in the treatment group (10.23 ± 1.97% vs. 4.53 ± 1.40%).ConclusionInhibition of JNK signaling can significantly suppress the growth of transplanted breast tumors in mice.

Chlorpyrifos induces apoptosis and autophagy in common carp lymphocytes by influencing the TCR γ-dependent PI3K/AKT/JNK pathway

Chlorpyrifos is an insecticide that is widely used in agricultural production. However, little is known about how chlorpyrifos disrupts lymphocyte homeostasis in common carp. Herein, we identified TCRγ through the results of transcriptome analysis. Subsequently, we established TCR γ knockdown and overexpression models in carp head kidney lymphocyte respectively using RNA interference and the pcDNA3.1 plasmid, respectively. Real-time PCR, fluorescent staining, ultrastructure observation and flow cytometry were used to detect the levels of the PI3K/AKT pathway, autophagy and apoptosis. Our results demonstrated that chlorpyrifos significantly decreased the expression of TCR γ, TCR γ suppression thereby induced increased mRNA expression of TNF-α, Bax, caspase-3, caspase-8, caspase-9 and significantly inhibited the expression of Bcl-2, which indicated that apoptosis was triggered. This conclusion was supported by our flow cytometry and ultrastructure observation results. In addition, the control and TCR γ overexpression groups had normal cell morphology. Moreover, TCR γ suppression activated the expression of Becline-1, ATG5, ATG10, ATG12, ATG16 and reduced the expression of mTOR, with the opposite results observed in the TCR γ overexpression group. Together, these results suggested that TCR γ imbalance triggers apoptosis and autophagy in lymphocyte. Moreover, we found that TCR γ knockdown significantly increased the mRNA expression of JNK and decreased the expression of PI3K and AKT, which indicated that the PI3K/AKT/JNK pathway was activated. Our results reported here indicated that chlorpyrifos induces apoptosis and autophagy in head kidney lymphocyte through the inhibition of TCR γ.

Transcriptomic analysis of genes involved in reproduction at different ages in Daphnia pulex (Branchiopoda, Cladocera)

Abstract Daphnia pulex is a freshwater microcrustacean that is known for its cyclical parthenogenesis. In D. pulex, parthenogenetic reproduction switches to sexual reproduction when the living conditions worsen. However, this transformation also occurs over age under favourable living conditions. Thus, there might be a relationship between aging and reproductive conversion. We performed Illumina RNA sequencing, generating 51 712 680 and 59 854 588 raw reads from 1 day-old D. pulex and 25 day-old D. pulex, respectively. From these reads, 60 776 transcripts were assembled and 36 569 (60.15%) unigenes were annotated. A number of significantly differentially expressed genes associated with growth, aging, and reproduction were identified and Quantitative real-time PCR for six genes confirmed the transcriptome data. RNA interference (RNAi) of the caspase-3 gene (casp3) that is a key gene for growth, development, aging, and reproduction, was conducted, which achieved an 80% reduction in casp3 mRNA expression. Meanwhile, the mRNA expression of upstream genes jnk and akt, and sir2 (encoding a substrate of casp3) were also detected. The change of jnk mRNA expression before and after RNAi was not significant () and the mRNA levels of sir2 decreased, while akt increased after casp3 RNAi (). The results indicated the interrelationships of some genes in the senescence pathway and helped to identify the molecular mechanism of the aging progress in D. pulex. Overall, the difference in mRNA expression profile during aging of D. pulex forms a basis for further studies aimed at understanding the role of the transcriptional level in regulating aging and reproductive transformation.

JNK and Akt genes in pancreatic tissue of diabetic rats and the effects of protein expression and phosphorylation modification

Objective To observe the effects of Yutang pill on pancreatic tissue, JNK, Akt gene, protein expression and phosphorylation of diabetic rats. Methods A total of 150 male SD rats were divided into blank group, model group, western medicine control group, Chinese medicine control group, Yutang Pill low dose group and Yutang pill high dose group according to random number table, 20 rats in each group. In addition to the blank group, the other groups of rats were prepared for the diabetes model. The western medicine control group was intragastrically administered with metformin hydrochloride suspension 0.09 g/kg, the Chinese medicine control group was administered with the suspension of glycoside tablets 2.43 g/kg, and the low-dose and high-dose groups of Yutang pills were respectively administered with Yutang pills 1.35 and 2.70 g/kg. The blank group and the model group were intragastrically administered with equal volume of saline. 1 time/d, 8 weeks. After continuous administration, the material was taken. The expression levels of JNK and Akt in pancreatic tissue were detected by Real-time PCR. The expression of JNK and Akt protein and phosphorylation in pancreatic tissue were detected by Western blot. Results Compared with the model group, the expression of JNK mRNA (0.57 ± 0.07, 0.95 ± 0.13 vs. 1.14 ± 0.19) and P-JNK/JNK (0.222 ± 0.038, 0.817 ± 0.104 vs. 1.140 ± 0.136) in the low- and high dose group significantly decreased (P<0.01). The expression of Akt mRNA (2.09 ± 0.13 vs. 1.63 ± 0.12) and P-Akt(Ser473)/ Akt (0.385 ± 0.072 vs. 0.130 ± 0.027) significantly increased (P<0.01). Conclusions The Yutang pill can reduce the expression of JNKmRNA in pancreatic tissue of T2DM rats and inhibit the phosphorylation of JNK protein. The expression of AktmRNA increased and the phosphorylation level of Akt protein increased. Key words: Diabetes mellitus; Yutang pill; C-Jun n-terminal kinase; Protein kinase B; Rats

The regulatory effect of flavonoids extracted from Abutilon theophrasti leaves on gene expression in LPS-induced ALI mice via the NF-κB and MAPK signaling pathways

Context: ALI is a common disease characterized by acute pulmonary inflammatory disorder. Abutilon theophrasti Medik. (Malvaceae), as a Chinese traditional medicine, is used for the treatment of inflammation. Its main constituents are flavonoid compounds.Objective: This study investigates the regulatory effect of a TFE from Abutilon theophrasti leaves on gene expression in LPS-induced ALI mice via the NF-κB and MAPK signaling pathways.Materials and methods: Kunming mice were intragastrically administered TFE (0.25, 0.5, 1.0 g/kg) for 5 days, and then ALI was induced via intranasal administration 40 μg of LPS in 10 μL PBS after intragastric administration on the 5th day, and PBS and DEX (2 mg/kg) were negative and positive control groups, respectively.Results: The relative expression of iNOS gene was 0.707, 0.507 and 0.483 for 0.25, 0.5 and 1.0 g/kg TFE, and COX-2 gene expression was also reduced after treatment by three concentrations of TFE with 0.768, 0.545, and 0.478. The mRNA expression levels of p65 were 0.61, 0.43 and 0.27 for 0.25, 0.5 and 1.0 g/kg TFE and IκB levels were increased in a dose-dependent manner with 3.99, 13.69 and 34.36. 0.5 and 1.0 g/kg TFE inhibited the expression of ERK1/2 with 0.59 and 0.38, p38MAPK with 0.62 and 0.54, and JNK with 0.37 and 0.29, and JNK mRNA expression was 0.60 for 0.25 g/kg TFE.Discussion and conclusion: These results indicate that the regulatory mechanisms of TFE on gene expression in LPS-induced ALI mice include inhibition of the NF-κB and MAPK signaling pathways.

Aβ1-42 regulates astrocytes through JNK/AP-1 pathway.

In Alzheimer's disease (AD), astrocytes are generally found in the surrounding of senile plaques participating in the production of phagocytosis and the removal of toxic compounds such as Aβ. This study aimed at investigating the effect of Aβ1-42 on astrocytes. Cellular viability of primary cultured astrocytes was analyzed using CCK-8 assay. Quantitative Real-time PCR was used to assess the mRNA expression of JNK and AP-1. The proteins of JNK/AP-1 pathway were investigated using Western blot. Our findings showed that Aβ1-42 inhibited cell viability and promoted apoptosis in astrocytes in primary culture. Additionally, Aβ1-42 increased the mRNA expression level of AP-1, but had no effect on the expression of JNK. Furthermore, Aβ1-42 increased the protein expression of p-JNK, p-c-jun and Fra-1 and the ratio of p-c-jun/c-jun and p-JNK/JNK. We showed that Aβ1-42 promoted cell apoptosis in astrocytes in primary culture. Furthermore, Aβ1-42 activated JNK/AP-1 pathway through promoting the phosphorylation of JNK, c-jun and Fra-1 expression, then inducing cell apoptosis.

The protective effect of lycopene on hypoxia/reoxygenation-induced endoplasmic reticulum stress in H9C2 cardiomyocytes

Nowadays, drugs protecting ischemia/reperfusion (I/R) myocardium become more suitable for clinic. It has been confirmed lycopene has various protections, but lacking the observation of its effect on endoplasmic reticulum stress (ERS)-mediated apoptosis caused by hypoxia/reoxygenation (H/R). This study aims to clarify the protective effect of lycopene on ERS induced by H/R in H9C2 cardiomyocytes. Detect the survival rate, lactic dehydrogenase (LDH) activity, apoptosis ratio, glucose-regulated proteins 78 (GRP78), C/EBP homologous protein (CHOP), c-Jun-N-terminal protein Kinase (JNK) and Caspase-12 mRNA and protein expression and phosphorylation of JNK (p-JNK) protein expression. LDH activity, apoptosis ratio and GRP78 protein expression increase in the H/R group, reduced by lycopene. The survival rate reduces in the H/R and thapsigargin (TG) groups; lycopene and 4-phenyl butyric acid (4-PBA) can improve it caused by H/R, lycopene also can improve it caused by TG. The apoptosis ratio, the expression of GRP78, CHOP and Caspase-12 mRNA and protein and p-JNK protein increase in the H/R and TG groups, weaken in the lycopene+H/R, 4-PBA+H/R and lycopene+TG groups. There is no obvious change in the expression of JNK mRNA or protein. Hence, our results provide the evidence that 10μM lycopene plays an obviously protective effect on H/R H9C2 cardiomyocytes, realized through reducing ERS and apoptosis. The possible mechanism may be related to CHOP, p-JNK and Caspase-12 pathways.

Identification and characterization of membrane androgen receptors in the ZIP9 zinc transporter subfamily: II. Role of human ZIP9 in testosterone-induced prostate and breast cancer cell apoptosis.

Recently, we discovered a cDNA in teleost ovarian follicle cells belonging to the zinc transporter ZIP9 subfamily (SLC39A9) encoding a protein with characteristics of a membrane androgen receptor (mAR). Here, we demonstrate that human ZIP9 expressed in MDA-MB-468 breast cancer cells and stably overexpressed in human prostate cancer PC-3 cells (PC-3-ZIP9) also displays the ligand binding and signaling characteristics of a specific, high-affinity mAR. Testosterone treatment of MDA-MB-468 and PC-3-ZIP9 cells caused activation of G proteins and second messenger pathways as well as increases in intracellular free zinc concentrations that were accompanied by induction of apoptosis. [1,2,6,7-(3)H]-testosterone binding and these responses were abrogated in MDA-MB-468 cells after ZIP9 small interfering RNA (siRNA) treatment and absent in PC-3 cells transfected with empty vector, confirming that ZIP9 functions as an mAR. Testosterone treatment caused up-regulation of proapoptotic genes Bax (Bcl-2-associated X protein), p53 (tumor protein p53), and JNK (c-Jun N-terminal kinases) in both cell lines and increased expression of Bax, Caspase 3, and cytochrome C proteins. Treatment with a zinc chelator or a MAPK inhibitor blocked testosterone-induced increases in Bax, p53, and JNK mRNA expression. The results suggest that both androgen signaling and zinc transporter functions of ZIP9 mediate testosterone promotion of apoptosis. ZIP9 is widely expressed in human tissues and up-regulated in malignant breast and prostate tissues, suggesting that it is a potential therapeutic target for treating breast and prostate cancers. These results provide the first evidence for a mechanism mediated by a single protein through which steroid and zinc signaling pathways interact to regulate physiological functions in mammalian cells.

Total flavonoids from Astragalus complanatus attenuates lung injury following paraquat poisoning in rats through inhibiting excessive endoplasmic reticulum stress and c-Jun N-terminal kinase pathway

To investigate the effect of total flavonoids from astragalus complanatus (FAC) on attenuating lung injury resulted from paraquat (PQ) poisoning by inhibiting excessive endoplasmic reticulum stress (ERS) and c-Jun N-terminal kinase (JNK) pathway in rat. Forty-eight Sprague-Dawley (SD) rats were randomly divided into six groups (n=8 in each group), including control group, model group, dimethyl sulfoxide (DMSO) vehicle control group, and FAC in low, medium, and high dosage groups. The model was reproduced by giving PQ 80 mg/kg orally to induce lung injury. The rats in control group were treated with saline by gavage. The rats in DMSO group were given 10% DMSO 20 mL/kg by gavage 2 hours before intraperitoneal injection of PQ, and those in FAC low, medium and high dosage groups received 40, 80, 160 mg×kg(-1)×d(-1) of FAC solution intraperitoneally after the PQ administration. The rats were sacrificed 72 hours after giving PQ, and the left lung tissue was harvested 72 hours after the reproduction of experimental model. The ratio of wet/dry weight (W/D) and total lung water content (TLW) were determined. The pathohistological changes of the left lung was observed under light microscope, and scored with alveolar damage index of quantitative assessment (IQA). The mRNA expressions of JNK and glucose regulated protein 78 (GRP78) were determined by reverse transcription-polymerase chain reaction (RT-PCR), and the protein expression of JNK, phosphorylation-JNK (p-JNK), and GRP78 were determined by Western Blot. Compared with control group, the W/D ratio, TLW and IQA were increased significantly in model group and DMSO group, and the mRNA expressions of JNK and GRP78 and the protein expressions of JNK, p-JNK and GRP78 were markedly increased. Compared with the model group, the W/D ratio, TLW and IQA, and the expressions of JNK mRNA and p-JNK protein were significantly decreased in the FAC groups, especially in FAC high dosage group [W/D ratio: 3.0±0.3 vs. 5.5±0.5, TLW: 2.2±0.3 vs. 4.7±0.4, IQA: (15.4±3.0)% vs. (40.0±5.7)%, JNK mRNA: 0.21±0.08 vs. 0.82±0.27, p-JNK protein: 0.31±0.09 vs. 0.78±0.25, all P<0.01]. The mRNA expression of GRP78 and the protein expressions of JNK and GRP78 were highly expressed in FAC low, medium and high dosage groups, and there was no significant difference compared with those in model group (GRP78 mRNA: 0.54±0.18 vs. 0.74±0.20, JNK protein: 0.76±0.27 vs. 0.80±0.28, GRP78 protein: 0.51±0.18 vs. 0.69±0.21, all P>0.05). PQ induces excessive ERS in the lung tissue resulting in lung injury. FAC has a protective effect on lung against PQ injury, and it may be related with inhibition JNK pathway in ERS.

Proteins controlling catabolic and stress pathways are upregulated during total knee arthroplasty

BACKGROUNDSkeletal muscle atrophy is common following total knee arthroscopy (TKA). A tourniquet is routinely used during TKA to create a bloodless field. Subsequent ischemia‐reperfusion (I/R) within muscle cells and tissue beds may activate cellular catabolic and stress pathways. We hypothesized that I/R increases gene expression and signaling proteins involved in muscle protein catabolism.PURPOSETo measure changes in transcripts and proteins involved in catabolic and stress pathways in older subjects undergoing TKA.METHODSSubjects between the ages 60–80 were studied in the operating room during surgery. Muscle biopsies were obtained at baseline (after anesthesia, immediately prior to tourniquet inflation), during maximal ischemia (just prior to tourniquet deflation), and during reperfusion.RESULTSTotal protein for FOXO3a, MAFbx, MuRF1, p‐38 MAPKs, and JNK were elevated relative to baseline during ischemia and reperfusion (p≤0.05). MAFbx, MuRF1, p‐38alpha, and JNK mRNA expression were increased during ischemia and reperfusion relative to baseline (p≤0.05).CONCLUSIONThese preliminary results suggest that I/R injury in muscle cells activates catabolic and stress pathways at the transcriptional and translational level during TKA in older adults.Support: NIH/NICHD K01HD057332.

Pan-neuronal knockdown of the c-Jun N-terminal Kinase (JNK) results in a reduction in sleep and longevity in Drosophila

Sleep is a unique behavioral state that is conserved between species, and sleep regulation is closely associated to metabolism and aging. The fruit fly, Drosophila melanogaster has been used to study the molecular mechanism underlying these physiological processes. Here we show that the c-Jun N-terminal Kinase (JNK) gene, known as basket (bsk) in Drosophila, functions in neurons to regulate both sleep and longevity in Drosophila. Pan-neuronal knockdown of JNK mRNA expression by RNA interference resulted in a decrease in both sleep and longevity. A heterozygous knockout of JNK showed similar effects, indicating the molecular specificity. The JNK knockdown showed a normal arousal threshold and sleep rebound, suggesting that the basic sleep mechanism was not affected. JNK is known to be involved in the insulin pathway, which regulates metabolism and longevity. A JNK knockdown in insulin-producing neurons in the pars intercerebralis had slight effects on sleep. However, knocking down JNK in the mushroom body had a significant effect on sleep. These data suggest a unique sleep regulating pathway for JNK.

The role of RhoA/Rho kinase signalling pathway in myocardial fibrosis in rats with type 2 diabetes

The role of RhoA/Rho kinase signalling pathway in myocardial fibrosis in rats with type 2 diabetes

Involvement of RhoA/ROCK in myocardial fibrosis in a rat model of type 2 diabetes

To investigate whether activation of RhoA/Rho kinase (ROCK) is involved in myocardial fibrosis in diabetic hearts. A rat model of type 2 diabetes was established using high fat diet combined with streptozotocin (30 mg/kg, ip). Animals were randomly divided into 3 groups: control rats, untreated diabetic rats that received vehicle and treated diabetic rats that received Rho-kinase inhibitor fasudil hydrochloride hydrate (10 mg·kg(-1)·d(-1), ip, for 14 weeks). Cardiac contractile function was evaluated in vivo. The morphological features of cardiac fibrosis were observed using immunohistochemistry and TEM. The mRNA expression of JNK, TGFβ1, type-I, and type-III procollagen was assessed with RT-PCR. The phosphorylation of MYPT1, JNK and Smad2/3, as well as the protein levels of TGFβ1 and c-Jun, were evaluated using Western blotting. In untreated diabetic rats, myocardial fibrosis was developed and the heart contractility was significantly reduced as compared to the control rats. In the hearts of untreated diabetic rats, the mRNA expression level and activity of JNK were upregulated; the expression of TGFβ1 and phosphorylation of Smad2/3 were increased. In the hearts of treated diabetic rat, activation of JNK and TGFβ/Smad was significantly decreased, myocardial fibrosis was reduced, and cardiac contractile function improved. The data suggest that fasudil hydrochloride hydrate ameliorates myocardial fibrosis in rats with type 2 diabetes at least in part through inhibiting the JNK and TGFβ/Smad pathways. Inhibition of RhoA/ROCK may be a novel therapeutic target for prevention of diabetic cardiomyopathy.