P38 MAPK Gene Expression Research Articles

Investigation of genetic stress parameters in brain tissues of rats exposed to 1.8 GHz cell phone radiofrequency electromagnetic field

Heat Shock Proteins (HSPs) may induce various cellular processes, including replication, apoptosis, cell-cycle progression. Mitogen-activated protein kinase (MAPK) cascades are the primary mechanism that mediates the cellular stress response to extracellular stimuli and regulates transcriptional activity. It has been shown that mobile phone exposure can stimulate the Hsp27/p38MAPK stress pathway. In this study, twenty-seven mature female Wistar albino rats were exposed to 1.8 GHz radiofrequency electromagnetic field (RF-EMF) 2h/day for 8 weeks (SAR: 0.06 W/kg). Hsp27 and p38MAPK gene expressions were investigated in rat brains. Rats were divided into groups sham-exposed, cage control, and 1.8 GHz RF-EMF exposed. Hsp27 and p38MAPK gene expression levels were investigated from the brain. p38MAPK expression was found to be upregulated in RF-EMF exposed group (p=0.018) Hsp27 expressions were not altered (p=0.897). In conclusion, long-term exposure to 1.8 GHz cell phone radiation can activate the Hsp27/p38MAPK stress pathway. It may cause several cellular disorders and can affect brain function.

Senescence ofbone marrow mesenchymal stem cells in Wistar malerats receiving normal chow/high-calorie diets with/without vitamin D.

Bone marrow mesenchymal stem cells (BM-MSCs) have a momentous function in the composition of the bone marrow microenvironment because of their many valuable properties and abilities, such as immunomodulation and hematopoiesis. The features and actions of MSCs are influenced by senescence, which may be affected by various factors such as nutritional/micronutrients status, e.g., vitamin D. This study aimed to examine the effects of a high-calorie diet (HCD) with/without vitamin D on BM-MSCs senescence. In the first phase, 48 middle-aged rats were fed a normal chow diet (NCD, n = 24) and an HCD (n = 24) for 26 weeks. Afterward, the rats in each group were randomly divided into three equal subgroups. Immediately, eight-rat from each diet group were sacrificed to assess the HCD effects on the first phase measurements. In the second phase, the remaining 4 groups of rats were fed either NCD or HCD with (6 IU/g) or without vitamin D (standard intake: 1 IU/g); in other words, in this phase, the animals were fed (a) NCD, (b) NCD plus vitamin D, (c) HCD, and (d) HCD plus vitamin D for 4 months. BM-MSCs were isolated and evaluated for P16INK4a, P38 MAPK, and Bmi-1 gene expression, reactive oxygen species (ROS) levels, SA-β-gal activity, and cell cycle profile at the end of both phases. After 26 weeks (first phase), the ROS level, SA-β-gal-positive cells, and cells in the G1 phase were significantly higher in HCD-fed rats than in NCD-fed ones (P < 0.05). HCD prescription did not significantly affect cells in the S and G2 phases (p > 0.05). Compared with the NCD-fed animals, P16INK4a and P38 MAPK gene expression were up-regulated in the HCD-fed animals; also, Bmi-1 gene expression was down-regulated (P < 0.05).BM-MSCs from vitamin D-treated rats (second phase) exhibited reduced mRNA levels of P16INK4a and P38 MAPK genes and increased Bmi-1 mRNA levels (all P<0.05). Vitamin D prescription also declined the percentage of SA-β-gal-positive cells, ROS levels, and the cells in the G1 phase and increased the cells in the S phase in both NCD and HCD-fed animals (P <0.05). The reduction of the cells in the G2 phase in rats fed with an NCD plus vitamin D was statistically non-significant (P=0.128) and significant in HCD plus vitamin D rats (P=0.002).HCD accelerates BM-MSCs senescence, and vitamin D reduces BM-MSCs senescence biomarkers.

Downregulation of TLR4-NF-?B-p38 MAPK Signalling in Cholestatic Rats Treated with Cranberry Extract.

&lt;b&gt;Background and Objective:&lt;/b&gt; Cholestasis is a liver disease that occurs when bile flow is restricted or blocked. Estrogen-induced cholestasis is marked by a reduction in bile flow and the accumulation of bile acids in the liver as well as liver damage. The aim was to evaluate the hepatoprotective effect on EE-induced cholestasis in rats of Cranberry Water Extract (CWE). &lt;b&gt;Materials and Methods:&lt;/b&gt; Adult albino rats weighing approximately 150±10 g were divided into six groups of six animals each. As control groups, three groups (I, II and IV) and three experimental groups were used (III, V, VI). &lt;b&gt;Results:&lt;/b&gt; Oral administration for 15 days of CWE (150 mg kg&lt;sup&gt;1&lt;/sup&gt; b.wt.) in EE-treated rats (100 μg kg&lt;sup&gt;1&lt;/sup&gt; 5 days b.wt.) improved serum cholesterol, bile acid and TBIL as well as hepatic SOD and GPx significantly. Also, CWE inhibited ALP, ALT, γ-GT activity as well as levels of TNF-α, NO, MMP-2 and MMP-9 and MDA in comparison with the EE treatment rats. On the other hand, the liver TLR4, NF-κB and p38MAPK gene expression was down regulated group of rats administrated with cranberry extract when compared with the EE-treated rats. CWE's prophylactic action II is more pronounced than prophylactic one. The hepatoprotective effects of cranberry in restoring normal liver functional ability were also supported by histopathological examination of liver tissues. &lt;b&gt;Conclusion:&lt;/b&gt; The results show clearly that cranberry extract has a strong prophylactic effect in EE-induced cholestasis by normalizing the levels of TLR4, NF-κB and p38MAPK gene expression.

The efficacy of Origanum majorana nanocubosomal systems in ameliorating submandibular salivary gland alterations in streptozotocin-induced diabetic rats

Diabetes mellitus is a challenging health problem. Salivary gland dysfunction is one of its complications. Current treatments possess numerous adverse effects. Therefore, herbal extracts have emerged as a promising approach for safe and effective treatment. However, they are required in large doses to achieve the desired effect. Accordingly, Origanum majorana extract (OE) was incorporated into nano-sized systems to enhance its biological effects at lower dosages. OE was standardized against rosmarinic acid (RA) and then loaded into nano-cubosomal (NC) systems via a 23 full-factorial design. Two optimum nano-systems at different drug loads (2.08 or 1.04 mg-RA/mL) were selected and assessed in vivo to compare their effects in streptozotocin-induced diabetic rats against conventional OE (2.08 mg-RA/mL). Blood glucose was evaluated weekly. Submandibular salivary glands were processed for histopathological examination and nuclear factor-erythroid 2-related factor 2 (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), and p38-MAPK gene expression analysis. NC systems were successfully prepared and optimized where the optimum systems showed nano-sized vesicles (210.4–368.3 nm) and high zeta potential values. In vivo results showed a significant lower blood glucose in all treated groups, with an exceptional reduction with NC formulations. Marked histopathological improvement was observed in all OE-treated groups, with OE-NC4 (2.08 mg-RA/mL) demonstrating the best features. This was supported by RT-PCR; where the OE-NC4 group recorded the highest mean value of Nrf2 and the least mean values of Keap1 and p38-MAPK, followed by OE-NC3 and OE groups. In conclusion, OE-loaded NC enhanced the anti-hyperglycemic effect of OE and ameliorated diabetic gland alterations compared to conventional OE. Thus, cubosomal nano-systems could be anticipated as potential carriers for the best outcome with OE.

Effect of Nano-eugenol and Aerobic Exercise Against the Streptozotocin Toxicity and Inflammatory Mediators P38-MAPK, NPY, and A-Rα2A in the Dorsal Root Ganglia of Diabetic Rats

Background: The aim of this study was to investigate the effects of nano-eugenol combined with aerobic exercise against the streptozotocin toxicity and inflammatory mediators P38-MAPK, NPY and A-Rα2A in the dorsal root ganglia of diabetic rats. Methods: Twenty-five, 8-week-old Wistar male rats were divided into 5 groups: 1) normal control group (normal model); 2) diabetic control group (diabetic model); 3), diabetic + exercise group (diabetic+exercise model); 4) diabetic group + nano-eugenol (diabetic+nano model); and 5) diabetic + exercise + nano-eugenol (diabetic+exercise+nano model). Diabetes was induced in the experimental groups 2 through 5 by the intraperitoneal injection of streptozotocin at 4mg/100 grams of the rats’ body weight. The nano-eugenol supplement was also gavaged into the supplement groups 4 and 5 only. Groups 3 and 5 exercised progressively at a speed of 8 to 20 meter/min for 5 to 30 min, five days a week over the 8-week study duration. Results: The diabetic rats that exercised and were treated with the nano-eugenol, showed a significant decrease in P38-MAPK gene expression compared to the normal model group (P=0.001). The study of the therapeutic modalities also showed that only the diabetic + exercise + nano-eugenol group showed a significant increase in NPY and A-Rα2A genes compared to the normal model (P=0.001). Conclusion: Based on the results, the use of nano-eugenol supplementation combined with aerobic exercise is likely to be effective in controlling the neurological damages due to diabetes by negatively regulating the P38-MAPK gene while positively regulating the NPY and A-Rα2A genes in the DRG region.

Beneficial effects of genistein in suppression of proliferation, inhibition of metastasis, and induction of apoptosis in PC3 prostate cancer cells

Objectives Beneficial effects of genistein have been studied in various cancer types but the underlying molecular mechanisms of its actions have not been well established. This study investigated the effects of genistein on caspase-3 and p38 mitogen-activated protein kinase (p38MAPK) as main cellular signalling targets in PC3 prostate cancer cells. Methods Caspase-3 and p38MAPK gene expression and intracellular protein levels were determined. Matrix metalloproteinase-2 (MMP2) gelatinase activity and caspase-3 enzyme activity were measured and PC3 cell migration and proliferation potencies were assessed. Results Genistein induced apoptosis by enhancing the gene expression, intracellular protein level, and enzyme activity of caspase-3. Genistein also inhibited cell proliferation by reducing p38MAPK gene expression and protein level and strongly suppressed metastatic potency of PC3 cells by reducing MMP2 activity. Conclusion Genistein exhibits its beneficial anticancer properties on PC3 cells by reducing metastatic potency and regulating caspase-3 and p38MAPK pathways at different transcriptional and protein levels.

The effect of exposure to 1800 MHz radiofrequency radiation on epidermal growth factor, caspase-3, Hsp27 and p38MAPK gene expressions in the rat eye.

Radiofrequency electromagnetic fields (RF-EMF) may induce DNA damage and oxidative stress in human lens epithelial cells (LECs). We aimed to investigate the expression levels of heat shock protein 27 (Hsp27), p38 mitogen-activated protein kinase (p38MAPK), epidermal growth factor receptor (EGFR) and caspase-3 gene expression levels in rat eye that was exposed to 1800 MHz RF-EMF. Thirty-seven female Wistar albino rats were divided into three groups. The rats in the study group (n = 9) were exposed to 1800 MHz RF-EMF at an electric field 6.8 ± 0.1 V/m and 0.06 W/kg specific absorption rate (SAR) for 2 hours per day for eight weeks. Sham group (n = 9) was kept under similar conditions as the exposed group without exposure to RF-EMF. The rats in all three groups were sacrificed and their eyes were removed. Hsp27, p38MAPK, EGFR, caspase-3 gene expression levels were investigated in detail with real-time polymerase chain reactions (Real-Time PCR). caspase-3 and p38MAPK gene expression were significantly upregulated in the ocular tissues following exposure to RF-EMF (p < 0.05). According to our findings, eye cells recognize EMF as a stress factor, and in response, activate caspase-3 and p38MAPK gene expressions. These results confirm that RF-EMF can cause cellular damage in rat ocular cells (Tab. 2, Fig. 3, Ref. 37).

Genistein Induces Apoptosis and Inhibits Proliferation of HT29 Colon Cancer Cells.

Soybean isoflavone genistein has multiple anticancer properties and its pro-apoptotic and anti-proliferative effects have been studied in different cancer cells. However, the mechanisms of action of genistein and its molecular targets on human colon cells have not been fully elucidated. Therefore, caspase-3 and p38mitogen-activated protein kinase (p38 MAPK) as the main therapeutic targets were investigated in this study at both gene expression and protein levels in HT29 colon cancer cells. The caspase-3 and p38 MAPK gene expression levels were examined by real time PCR whereas flow cytometry technique was performed to determine their intracellular protein levels. The caspase-3 enzyme activity was obtained by colorimetric method while the gelatinase activity of matrix metalloproteinase-2 (MMP2) was determined by zymography. In addition, MTT test, wound healing assay and clonogenic assay were carried out to determine the effect of genistein on HT29 cell viability, migration, and proliferation, respectively. Genistein induced apoptotic death in HT29 cells through activation of caspase-3 pathway at the transcriptional, protein, and enzymatic levels. Moreover, genistein inhibited the proliferation of HT29 cells by reducing of both p38 MAPK gene expression and its active phosphorylated protein level. Also, we showed that genistein strongly suppressed the metastatic potency of HT29 colon cancer cells via the reduction of MMP2 activity. Based on the results of this study, we conclude that genistein may exhibit its anticancer properties on HT29 colon cancer cells by modulating caspase-3 and p38 MAPK pathway at different transcriptional and protein levels.

Immunity decreases, antioxidant system damages and tight junction changes in the intestine of grass carp (Ctenopharyngodon idella) during folic acid deficiency: Regulation of NF-κB, Nrf2 and MLCK mRNA levels.

This investigation used the same growth trial as the previous study, which showed that folic acid deficiency retarded growth in young grass carp (the percent weight gain of Groups 1-6 were 102.32±3.41%, 137.25±10.48%, 179.78±3.95%, 164.33±3.21%, 143.35±8.12% and 115.28±2.66%) [1]. In the present study, we investigated the effects of dietary folic acid on the immune response, antioxidant status and tight junctions in the intestine of young grass carp (Ctenopharyngodon idella). A total of 540 young grass carp were fed diets containing graded levels of folic acid at 0.10, 0.47, 1.03, 1.48, 1.88 and 3.12mgkg(-1) diet for 8 weeks. The results indicated that acid phosphatase and lysozyme activities, and the complement component 3 content in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) were decreased with folic acid deficiency (0.1mgkg(-1))(P<0.05). Folic acid deficiency (0.1mgkg(-1)) up-regulated interleukin 1β, interleukin 8, tumor necrosis factor α, nuclear factor κB p65 (NF-κB p65), IκB kinase α (IKK-α), IKK-β and IKK-γ gene expression, meanwhile down-regulated interleukin 10, transforming growth factor β, IκB and target of rapamycin gene expression in the PI, MI and DI (P<0.05). These data suggested that folic acid deficiency decreased fish intestinal innate immune function may be partly contributed to the regulation of NF-κB p65 pathway. Moreover, the activities and corresponding gene expression of glutathione content, Cu/Zn superoxide dismutase, catalase, glutathione peroxidase, glutathione s-transferases and glutathione reductase in fish intestine were depressed by deficient folic acid diet (0.1mgkg(-1))(P<0.05). Furthermore, folic acid deficiency (0.1mgkg(-1)) down-regulated NF-E2-related factor 2 (Nrf2) gene expression, up-regulated Kelch-like-ECH-associated protein 1a (Keap1a) and Keap1b gene expression in fish intestine (P<0.05). These data indicated that deficient folic acid diet damaged fish intestinal antioxidant capacity partly by regulating Nrf2/Keap1 pathway. Additionally, folic acid deficiency (0.1mgkg(-1)) down-regulated claudin-b, claudin-c, claudin-3, occludin and zonula occludens 1 gene expression; whereas folic acid deficiency (0.1mgkg(-1)) up-regulated claudin-12, claudin-15, myosin light chain kinase (MLCK) and p38 mitogen activated protein kinase (p38 MAPK) gene expression in the PI, MI and DI (P<0.05), suggesting that folic acid deficiency may damage fish intestinal tight junctions associated with the mediation of MLCK and p38 MAPK gene expression. In conclusion, folic acid deficiency (0.1mgkg(-1)) impaired fish intestinal immunity, antioxidant capacity and tight junctions.

Acute alcohol modulates cardiac function as PI3K/Akt regulates oxidative stress.

Clinical manifestations of alcohol abuse on the cardiac muscle include defective contractility with the development of heart failure. Interestingly, low alcohol consumption has been associated with reduced risk of cardiovascular disease. Although several hypotheses have been postulated for alcoholic cardiomyopathy and for the low-dose beneficial cardiovascular effects, the precise mechanisms and mediators remain largely undefined. We hypothesize that modulation of oxidative stress by PI3K/Akt plays a key role in the cardiac functional outcome to acute alcohol exposure. Thus, acutely exposed rat cardiac tissue and cardiocytes to low (LA: 5 mM), moderate (MA: 25 mM), and high (HA: 100 mM) alcohol were assessed for markers of oxidative stress in the presence and absence of PI3K/Akt activators (IGF-1 0.1 μM or constitutively active PI3K: Ad.BD110 transfection) or inhibitor (LY294002 1 μM or Akt-negative construct Ad.Akt(K179M) transfection). Acute LA reduced Akt, superoxide dismutase (SOD-3) and NFκB, ERK1, and p38 MAPK gene expression. Acute HA only increased that of SOD-3 and NFκB. These effects were generally inhibited by Ad.Akt(K179M) and enhanced with Ad.BD110 transfection. In parallel, LA reduced but HA enhanced Akt activity, which was reversed by IGF-1 and inhibited by Ad.Akt(K179M), respectively. Also, LA reduced caspase 3/7 activity and oxidative stress, while HA increased both. The former was blocked, while the latter effect was enhanced by Ad.Akt(K179M). The reverse was true with PI3K/Akt activation. This translated into reduced viability with HA, with no effect with LA. On the functional level, acute LA improved cardiac output and ejection fraction, mainly through increased stroke volume. This was accompanied with enhanced end-systolic pressure-volume relationship and preload recruitable stroke work. Opposite effect was recorded for HA. LA and HA in vivo functional effects were alleviated by LY and enhanced by IGF-1 treatment. Acute LA and HA seem to oppositely affect cardiac function through modulation of oxidative stress where PI3K/Akt plays a pivotal role.

Transforming Growth Factor-β Suppressed Id-1 Expression in a smad3-Dependent Manner in LoVo Cells

TGF-beta plays an important role in regulating cell differentiation and proliferation in human cancers such as colorectal cancer. Id-1 has been identified as a marker in colorectal cancer progression. The aim of this study was to investigate the role of TGF-beta in regulating Id-1 in LoVo cells. siRNA was used to silence smad2, smad3, and p38 MAPK gene expression in Lovo cells. Interference efficiency and the role of TGF-beta on Id-1 expression were analyzed using a luciferase reporter assay, RT-PCR, and Western blotting. Cell viability was determined using the MTT assay. In this study, we demonstrated that TGF-beta1 downregulated Id-1 protein expression in LoVo cells. Smad2 and smad3 siRNA inhibited TGF-beta1-induced 4xSBE luciferase reporter activity. p38 MAPK siRNA inhibited TGF-beta1-induced 3xAP-1 luciferase reporter activity. However, the suppression of Id-1 by TGF-beta1 was recovered by smad3 siRNA but not smad2 or p38 MAPK siRNA. Moreover, TGF-beta1 stimulated cellular proliferation and p21(Waf1) protein expression, which might be mediated by suppressing Id-1 expression. In conclusion, this study demonstrated that TGF-beta1 suppressed Id-1 expression in a smad3-dependent manner in LoVo cells using RNAi technology. These results provide new insight into the mechanisms of TGF-beta function in colorectal cancer cells.

MKK3/6—p38 MAPK negatively regulates murine MMP-13 gene expression induced by IL-1β and TNF-α in immortalized periodontal ligament fibroblasts

Matrix metalloprotease-13 (MMP-13) or collagenase-3 is involved in a number of pathologic processes such as tumor metastasis and angiogenesis, osteoarthritis, rheumatoid arthritis and periodontal diseases. These conditions are associated with extensive degradation of both connective tissue and bone. This report examines gene regulation mechanisms and signal transduction pathways involved in Mmp-13 expression induced by proinflammatory cytokines in periodontal ligament (PDL) fibroblasts. Mmp-13 mRNA expression was increased 10.7 and 9.5 fold after stimulation with IL-1beta (5 ng/mL) and TNF-alpha (10 ng/mL), respectively. However, inhibition of p38 MAPKinase with SB203580 resulted in significant (p<0.001) induction (23.2 and 18.1 fold, respectively) of Mmp-13 mRNA as assessed by real time PCR. Negative regulation of IL-1beta induced Mmp-13 expression was confirmed by inhibiting p38 MAPK gene expression with siRNA. Transient transfection of dominant negative forms of MKK3 and MKK6 also resulted in increased levels of Mmp-13 mRNA after IL-1beta stimulation. Mmp-13 mRNA expression induced by TNF-alpha was decreased by JNK and ERK inhibition. Western blot and zymogram analysis indicated that Mmp-13 protein expression induced by the proinflammatory cytokines were also upregulated by inhibition of p38 MAPK. Reporter gene experiments using stable cell lines harboring 660-bp sequence of the murine Mmp-13 proximal promoter indicated that transcriptional mechanisms were at least partially involved in this negative regulation of Mmp-13 expression by p38 MAPK and upstream MKK3/6. These results suggest a negative transcriptional regulatory mechanism mediated by p38 MAPK and upstream MKK3/6 on Mmp-13 expression induced by proinflammatory cytokines in PDL fibroblasts.