Resistance to apoptosis is a mechanism of adaptation of rat stomach to aspirin

2000 ◽  
Vol 278 (6) ◽  
pp. G839-G846 ◽  
Author(s):  
Barbara M. Alderman ◽  
Gregory A. Cook ◽  
Mary Familari ◽  
Neville D. Yeomans ◽  
Andrew S. Giraud

Adaptation of the gastric mucosa to nonsteroidal anti-inflammatory drug-induced injury is a well-documented phenomenon, but the mechanisms are not known. We investigated whether changes in stress protein expression and apoptosis play roles in adaptation of rat stomach to aspirin. RT-PCR and Western blotting techniques were used to analyze mRNA and protein expression of HSP72 and HSP90 and cleavage of caspase 3 protein. Apoptosis was detected by the TUNEL method and quantified. HSP72 mRNA and protein expression was unchanged in adapted mucosa, whereas HSP90 mRNA and protein levels decreased. Caspase 3 protein was activated, and the number of apoptotic cells increased in mucosa after one aspirin dose. However, in adapted mucosa after aspirin, activated caspase 3 and the number of apoptotic cells had returned to basal levels. Induction of the stress response was found not to be a mechanism of mucosal adaptation against multiple doses of aspirin. Our results lead us to propose instead that resistance to aspirin-induced apoptosis plays a role in the protective phenomenon of adaptation.

2001 ◽  
Vol 280 (5) ◽  
pp. G958-G967 ◽  
Author(s):  
Takayoshi Kiba ◽  
Satoru Saito ◽  
Kazushi Numata ◽  
Yasuhiro Kon ◽  
Tetsuya Mizutani ◽  
...  

We examined whether the Fas (APO-1/CD95)/Fas ligand system mediates apoptosis in rats with ventromedial hypothalamus (VMH) lesions. Northern and Western blotting indicated that VMH lesions lead to a significant increase in Fas mRNA and protein expression from day 1 to day 7 and in Fas ligand mRNA and protein expression from day 2 to day 7. Immunohistochemistry indicated that the region of strongest Fas expression shifted from acinar zone 1 to zones 2 and 3 by day 7 after VMH lesioning and that at days 2–7Fas-ligand-positive hepatocyte cell membranes and cytoplasm were randomly distributed in acinar zones 1–3. We also analyzed activation of caspase 3-like proteases in hepatocytes, Kupffer cells, and sinusoidal endothelial cells. Spectrofluorometric assay demonstrated that caspase 3-like activity significantly increased only in hepatocytes after VMH lesioning. Moreover, electron microscopy and TUNEL assay showed that VMH lesions induced apoptosis. All of these effects were completely inhibited by hepatic vagotomy and administration of atropine. Vagal firing after VMH lesioning may stimulate Fas/Fas ligand system-mediated apoptosis through the cholinergic system in the rat liver.


2019 ◽  
Author(s):  
Zhixiong Chen ◽  
Jing Wang ◽  
Anquan Yang ◽  
Lihua Zhang ◽  
Yaojia Lu ◽  
...  

Abstract Background: Previous studies demonstrated that pearl extract (PE) promotes wound healing and skin whitening. However, whether PE can inhibit ultraviolet (UV) photodamage in HaCaT cells remains unclear. In this study, an in vitro photoaging cell model was established to observe the effect of PE on UV-induced damage and apoptosis of HaCaT cells. The aim was to provide a reference for future development of natural sunscreen agents. Results: PE concentrations of 0.1 and 1 μg/mL were considered as the most effective and safe concentrations. Compared to the control group, superoxide dismutase and glutathione peroxidase activities in the photoaging group were significantly reduced, while malondialdehyde and reactive oxygen species content, along with tumor necrosis factor-alpha (TNF-a) and interleukin (IL)-10 mRNA and protein levels were markedly increased. In contrast, Bcl-2 protein expression was significantly decreased, while caspase-3, caspase-9, and Bax protein expression levels were significantly increased. Compared to the photoaging group, HaCaT cell proliferation was significantly increased in the PE group. Both PE concentrations significantly increased superoxide dismutase and glutathione peroxidase activities in cells, reduced malondialdehyde and reactive oxygen species content, decreased TNF-a and IL-10 mRNA expression in cells, and reduced TNF-a and IL-10 protein levels in the supernatant. Additionally, Bcl-2 protein expression levels were significantly increased, while caspase-3, caspase-9, and Bax protein expression levels were significantly reduced by PE treatment. Conclusions: PE can inhibit UV-induced apoptosis by inhibiting mitochondria-mediated apoptosis and regulating TNF-a and IL-10 expression.


2012 ◽  
Vol 90 (12) ◽  
pp. 1569-1575 ◽  
Author(s):  
Jian-Zhe Li ◽  
Shu-Yi Yu ◽  
Jian-Hua Wu ◽  
Qing-Rui Shao ◽  
Xiao-Min Dong

Increased intracellular reactive oxygen species (ROS) are involved in doxorubicin (DOX)-induced myocardial cell apoptosis, and paeoniflorin (PEF) has been shown to exert an antioxidant effect. The aim of the present study was to explore the protective effect of PEF on DOX-induced myocardial cell apoptosis and the underlying mechanisms. In cultured H9c2 cells, different concentrations (1, 10, or 100 μmol/L) of PEF was added for 2 h prior to exposure to DOX (5 μmol/L) for 24 h. Cell apoptosis was evaluated by hoechst 33342 staining, and caspase-3 expression and activity. The mRNA and protein expression of NADPH oxidase (NOX) 2 and NOX4 was determined by real-time polymerase chain reaction and Western blot, respectively. Intracellular ROS and NOX activity were measured by assay kit. The results showed that DOX significantly increased myocardial cell apoptosis, increased caspase-3 expression and activity concomitantly with enhanced ROS production, and increased NOX2, NOX4 mRNA and protein expression, and NOX activity. These effects were remarkably inhibited by pretreatment of PEF. Our results suggested that PEF has a protective effect against DOX-induced myocardial cell apoptosis through a mechanism involving a decrease in ROS production by inhibition of NOX2, NOX4 expression, and NOX activity.


2020 ◽  
Author(s):  
Zhixiong Chen ◽  
jing wang ◽  
Anquan Yang ◽  
Lihua Zhang ◽  
Yaojia Lu ◽  
...  

Abstract Background: Previous studies have demonstrated that pearl extract (PE) promotes wound healing and skin whitening. However, it remains unclear whether PE can inhibit ultraviolet (UV)-photodamage in HaCaT cells. In this study, an in vitro photoaging cell model was established to observe the effect of PE on UV-induced damage and the apoptosis of HaCaT cells. The aim of this study was to provide a reference for the future development of natural sunscreens.Results: PE concentrations of 0.1 and 1 μg/mL were considered the most effective and safe concentrations. Compared to that in the control group, superoxide dismutase and glutathione peroxidase activity in the photoaging group was significantly reduced, whereas malondialdehyde and reactive oxygen species content, along with tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-10 mRNA and protein levels, were markedly increased. In contrast, Bcl-2 protein expression was significantly decreased, whereas caspase-3, caspase-9, and Bax protein expression levels were significantly increased. Compared to that in the photoaging group, HaCaT cell proliferation was significantly increased in the PE group. Both PE concentrations significantly increased superoxide dismutase and glutathione peroxidase activity in cells, reduced malondialdehyde and reactive oxygen species content, decreased TNF-α and IL-10 mRNA expression in cells, and reduced TNF-α and IL-10 protein levels in the supernatant. Additionally, Bcl-2 protein expression levels were significantly increased, whereas caspase-3, caspase-9, and Bax protein expression levels were significantly reduced by PE treatment.Conclusions: PE can inhibit UV-induced apoptosis by inhibiting mitochondria-mediated apoptosis and regulating TNF-α and IL-10 expression.


Author(s):  
Priyanka Singh ◽  
Sanjay Kumar Bhadada ◽  
Divya Dahiya ◽  
Uma Nahar Saikia ◽  
Ashutosh Kumar Arya ◽  
...  

Abstract Purpose Glial cells missing 2 (GCM2), a zinc finger-transcription factor, is essentially required for the development of parathyroid glands. We sought to identify if the epigenetic alterations in the GCM2 transcription are involved in the pathogenesis of sporadic parathyroid adenoma. In addition, we examined the association between promoter methylation and histone modifications with disease indices. Experimental design mRNA and protein expression of GCM2 were analyzed by RT-qPCR and immunohistochemistry in 33 adenomatous and 10 control parathyroid tissues. DNA methylation and histone methylation/acetylation of GCM2 promoter were measured by bisulfite sequencing and ChIP-qPCR. Additionally, we investigated the role of epigenetic modifications on GCM2 and DNA methyltransferase 1 (DNMT1) expression in PTH-C1 cells by treating with 5-aza 2’deoxycytidine (DAC) and BRD4770 and assessed for GCM2 mRNA and DNMT1 protein levels. Results mRNA and protein expression of GCM2 were lower in sporadic adenomatous than in control parathyroid tissues. This reduction correlated with hypermethylation (P<0.001) and higher H3K9me3 levels in GCM2 promoter (P<0.04) in adenomas. In PTH-C1 cells, DAC treatment resulted in increased GCM2 transcription and decreased DNMT1 protein expression, while cells treated with the BRD4770 showed reduced H3K9me3 levels but a non-significant change in GCM2 transcription. Conclusion These findings suggest the concurrent association of promoter hypermethylation and higher H3K9me3 with the repression of GCM2 expression in parathyroid adenomas. Treatment with DAC restored GCM2 expression in PTH-C1 cells. Our results showed a possible epigenetic landscape in the tumorigenesis of parathyroid adenoma and also that DAC may be promising avenues of research for parathyroid adenoma therapeutics.


2000 ◽  
Vol 278 (2) ◽  
pp. F238-F245 ◽  
Author(s):  
Ian V. Silva ◽  
Carol J. Blaisdell ◽  
Sandra E. Guggino ◽  
William B. Guggino

Mutations in the chloride channel, ClC-5, have been described in several inherited diseases that result in the formation of kidney stones. To determine whether ClC-5 is also involved in calcium homeostasis, we investigated whether ClC-5 mRNA and protein expression are modulated in rats deficient in 1α,25(OH)2 vitamin D3 with and without thyroparathyroidectomy. Parathyroid hormone (PTH) was replaced in some animals. Vitamin D-deficient, thyroparathyrodectomized rats had lower serum and higher urinary calcium concentrations compared with control animals as well as lower serum PTH and calcitonin concentrations. ClC-5 mRNA and protein levels in the cortex decrease in vitamin D-deficient, thyroparathyroidectomized rats compared with both control and vitamin D-deficient animals. ClC-5 mRNA and protein expression increase near to control levels in vitamin D-deficient, thyroparathyroidectomized rats injected with PTH. No significant changes in ClC-5 mRNA and protein expression in the medulla were detected in any experimental group. Our results suggest that PTH modulates the expression of ClC-5 in the kidney cortex and that neither 1α,25(OH)2 vitamin D3 nor PTH regulates ClC-5 expression in the medulla. The pattern of expression of ClC-5 varies with urinary calcium. Animals with higher urinary calcium concentrations have lower levels of ClC-5 mRNA and protein expression, suggesting that the ClC-5 chloride channel plays a role in calcium reabsorption.


2000 ◽  
Vol 7 (6) ◽  
pp. 574-586 ◽  
Author(s):  
G Tudor ◽  
A Aguilera ◽  
D O Halverson ◽  
N D Laing ◽  
E A Sausville

2020 ◽  
Vol 103 (3) ◽  
pp. 608-619
Author(s):  
Ping Zhong ◽  
Jin Liu ◽  
Hong Li ◽  
Senbin Lin ◽  
Lingfeng Zeng ◽  
...  

Abstract This study aimed to investigate whether cadmium (Cd) cytotoxicity in rat ovarian granulosa cells (OGCs) is mediated through apoptosis or autophagy and to determine the role of microRNAs (miRNAs) in Cd cytotoxicity. To test this hypothesis, rat OGCs were exposed to 0, 10, and 20 μM CdCl2 in vitro. As the Cd concentration increased, OGC apoptosis increased. In addition, Cd promoted apoptosis by decreasing the mRNA and protein expression levels of inhibition of B-cell lymphoma 2 (Bcl2). However, under our experimental conditions, no autophagic changes in rat OGCs were observed, and the mRNA and protein expression levels of the autophagic markers microtubule-associated protein 1 light chain 3 alpha (Map1lc3b) and Beclin1 (Becn1) were not changed. Microarray chip analysis, miRNA screening, and bioinformatics approaches were used to further explore the roles of apoptosis regulation-related miRNAs. In total, 19 miRNAs putatively related to Cd-induced apoptosis in rat OGCs were identified. Notably, miR-204-5p, which may target Bcl2, was identified. Then, rat OGCs were cultured in vitro and used to construct the miR-204-5p-knockdown cell line LV2-short hairpin RNA (shRNA). LV2-shRNA cells were exposed to 20 μM Cd for 12 h, and the mRNA and protein expression levels of Bcl2 were increased. Our findings suggest that Cd is cytotoxic to rat OGCs, and mitochondrial apoptosis rather than autophagy mediates Cd-induced damage to OGCs. Cd also affects apoptosis-related miRNAs, and the underlying apoptotic mechanism may involve the Bcl2 gene.


J ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 181-194 ◽  
Author(s):  
René Huber ◽  
Bruno Stuhlmüller ◽  
Elke Kunisch ◽  
Raimund W. Kinne

Rheumatoid arthritis (RA) is a chronic inflammatory and destructive joint disease characterized by overexpression of pro-inflammatory/pro-destructive mediators, whose regulation has been the focus of our previous studies. Since the expression of these proteins commonly depends on AP-1, the expression of the AP-1-forming subunits cJun, JunB, JunD, and cFos was assessed in synovial membrane (SM) samples of RA, osteoarthritis (OA), joint trauma (JT), and normal controls (NC) using ELISA and qRT-PCR. With respect to an observed discrepancy between mRNA and protein levels, the expression of the mRNA stability-modifying factors AU-rich element RNA-binding protein (AUF)-1, tristetraprolin (TTP), and human antigen R (HuR) was measured. JunB and JunD protein expression was significantly higher in RA-SM compared to OA and/or NC. By contrast, jun/fos mRNA expression was significantly (cjun) or numerically decreased (junB, junD, cfos) in RA and OA compared to JT and/or NC. Remarkably, TTP and HuR were also affected by discrepancies between their mRNA and protein levels, since they were significantly decreased at the mRNA level in RA versus NC, but significantly or numerically increased at the protein level when compared to JT and NC. Discrepancies between the mRNA and protein expression for Jun/Fos and TTP/HuR suggest broad alterations of post-transcriptional processes in the RA-SM. In this context, increased levels of mRNA-destabilizing TTP may contribute to the low levels of jun/fos and ttp/hur mRNA, whereas abundant mRNA-stabilizing HuR may augment translation of the remaining mRNA into protein with potential consequences for the composition of the resulting AP-1 complexes and the expression of AP-1-dependent genes in RA.


Sign in / Sign up

Export Citation Format

Share Document