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Mitophagy is the selective degradation of damaged mitochondria, and it is of great significance to maintain the normal quantity and quality of mitochondria to ensure cell homeostasis and survival. Necroptosis is a type of programmed cell necrosis that can be induced by excessive mitophagy. Reactive oxygen species (ROS) are produced mainly by mitochondria and can damage mitochondria. Hyperoxic acute lung injury (HALI) is a serious complication of clinical oxygen therapy, and its pathogenesis is not clear. Existing studies have shown that mitophagy and necroptosis are involved in the occurrence of HALI. There are many mechanisms regulating mitophagy and necroptosis, including tumor necrosis factor-α (TNF-α), E3 ubiquitin protein ligase (PINK1/Parkin) protein pathway encoded by PTEN-induced kinase 1/PARK2 gene, phosphoglycerate mutase 5 (PGAM5), etc. PGAM5 has been proved to be a key factor linking mitophagy and necroptosis. Previous studies of our team found that the mechanism of microRNA-21-5p (miR-21-5p) alleviating HALI was related to its pGAM5-mediated inhibition of mitophagy, but the mechanism of PGAM5-mediated mitophagy and necroptosis remains unclear. Therefore, this paper reviews the targets of PGAM5-mediated mitophagy and necroptosis, in order to find clues of lung protection of pGAM5-mediated mitophagy and necroptosis in HALI, and provide theoretical basis for subsequent basic research.
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Objective:To evaluate the role of phosphoglycerate mutase 5 (phosphoglycerate mutase family member 5, PGAM5) in myocardial ischemia-reperfusion (I/R) injury in diabetic rats and the relationship with mitochondrial quality.Methods:SPF healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 200-220 g, were used in this study.Type 1 diabetes mellitus was induced by 1% streptozotocin diluted in citrate buffer solution 60 mg/kg.The rats were continuously fed for 8 weeks after successful establishment of the model.Seventy-two rats with type 1 diabetes mellitus were divided into 4 groups ( n=18 each) by a random number table method: diabetic sham operation group (DS group), diabetic myocardial I/R group (DIR group), diabetic myocardial I/R plus AAV9-PGAM5 shRNA group (DIR+ PGAM5 shRNA group), and diabetic myocardial I/R plus AAV9-GFP group (DIR+ GFP group). The myocardial I/R model was established by ligation of the left anterior descending coronary artery for 30 min followed by reperfusion for 2 h starting from 8 weeks after establishment of type 1 diabetes mellitus model.AAV9-PGAM5 shRNA and AAV9-GFP 2×10 12 μg/kg were slowly injected via tail vein 3 weeks before ischemia.In group AAV9-PGAM5 shRNA, left ventricular systolic pressure (LVSP) and the maximum rate of increase or decrease in left ventricular systolic pressure (±dp/dt max) were monitored and recorded at the end of reperfusion, and then blood samples from the the right carotid artery were collected for determination of serum troponin Ⅰ(cTnI), creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) levels (by enzyme-linked immunosorbent assay). The animals were sacrificed and hearts were obtained for determination of myocardial infarct size (by Evans Blue plus TTC double staining method) and expression of PGAM5, autophagy-related proteins (LC3B, p62), dynamin-related protein 1 (Drp1), and mitochondrial autophagy receptor protein (FUNDC1) (by Western blot) and for microscopic examination of pathological changes of myocardial tissues (by HE staining). Results:Compared with group DS, the LVSP and ±dp/dt max were significantly decreased, the serum levels of cTnI, CK-MB and LDH were increased, myocardial infarct size was increased, the expression of PGAM5, LC3B, Drp1 and FUNDC1 was up-regulated, and the expression of p62 was down-regulated in group DIR and group DIR+ GFP ( P<0.05). Compared with group DIR, LVSP and ±dp/dt max were significantly increased, the serum levels of cTnI, CK-MB and LDH were decreased, myocardial infarct size was decreased, the expression of PGAM5, LC3B, Drp1 and FUNDC1 was down-regulated, and the expression of p62 was up-regulated in group DIR+ PGAM5 shRNA ( P<0.05), and no significant change was found in the parameters mentioned above in group DIR+ GFP ( P>0.05). Conclusion:PGAM5 is involved in the myocardial I/R injury in diabetic rats, which is related to the reduction of mitochondrial quality.
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Objective To investigate the effect and its molecular mechanism of phosphoglycerate mutase 5 (PGAM5) mediated pyroptosis on liver ischemia-reperfusion injury (IRI). Methods C57 mouse models of liver IRI were established and randomly divided into the 6 h reperfusion (6 h group) and 12 h reperfusion (12 h group), and sham operation group (sham group) was established too, 10 rats in each group. The effect of IRI on the parameters in the liver tissues and serum samples was evaluated. The expression levels of PGAM5 and cysteinyl aspartate specific proteinase (Caspase)-1 in the liver tissues during IRI were quantitatively detected. The IRI models of liver cells were established (IRI group). The IRI models of liver cells were established after pretreatment with Caspase-1 inhibitor Z-YVAD-FMK (inhibitor group). The untreated AML12 cells were allocated into the control group. The effect of inhibiting Caspase-1 activity on pyroptosis was analyzed. AML12 cells were transfected with PGAM5 small interfering ribonucleic acid (siRNA) (siRNA group) and siRNA-negative control (siRNA-NC) (siRNA-NC group) by liposome 3000, and then IRI models of liver cells were established. The untreated AML12 cells were assigned into the control group. The effect of PGAM5 mediated pyroptosis on IRI of liver cells was assessed. Results In the 6 h and 12 h groups, partial liver cell edema, hepatic sinusoid narrowing, central vein congestion and occasional spot necrosis were observed in the mouse liver tissues, and these changes in the 12 h group were more aggravated than those in the 6 h group. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the 6 h and 12 h groups were higher than those in the sham group, and the values in the 12 h group were higher than those in the 6 h group. The levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β were increased in the 6 h and 12 h groups, and the values in the 12 h group were lower than those in the 6 h group. The relative expression levels of IL-1β messenger ribonucleic acid (mRNA) in the mouse liver tissues in the 6 h and 12 h groups were up-regulated, and the value in the 12 h group was lower than that in the 6 h group. The cell apoptosis rates in the liver tissues were significantly increased in the 6 h and 12 h groups, and the value in the 12 h group was remarkably lower than that in the 6 h group (P < 0.01-0.05). Compared with the sham group, the relative expression levels of PGAM5 mRNA and protein in the mouse liver tissues in the 6 h and 12 h groups were significantly up-regulated, and the values in the 12 h group were significantly higher than those in the 6 h group (P < 0.01-0.05). The protein expression levels of PGAM5 and Caspase-1 in the liver tissues were up-regulated in the 6 h and 12 h groups. Compared with the control group, the relative expression levels of NOD-like receptor protein 3 (NLRP3), cleaved Caspase-1 and Gasdermin D (GSDMD) proteins were up-regulated and the fluorescence intensity of GSDMD was increased in the IRI group. Compared with the IRI group, the relative expression levels of NLRP3, cleaved Caspase-1 and GSDMD proteins were significantly down-regulated and the fluorescence intensity of GSDMD was considerably decreased in the inhibitor group (P < 0.01-0.05). Compared with the control group, the cell survival rate was significantly decreased, and the relative expression levels of PGAM5, NLRP3, cleaved Caspase-1 and GSDMD proteins were significantly up-regulated in the siRNA-NC group (P < 0.01-0.05). Compared with the siRNA-NC group, the cell survival rate was remarkably increased, whereas the relative expression levels of PGAM5, NLRP3, cleaved Caspase-1 and GSDMD proteins were significantly down-regulated in the siRNA group (P < 0.01-0.05). Conclusions PGAM5 may aggravate the liver IRI in mouse models probably by mediating pyroptosis via PGAM5/Caspase-1/GSDMD signaling pathway and aggravating liver cell injury.
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Objective@#To investigate the expression of phosphoglycerate mutase 1 (PGAM1) in the mouse testis after exposure to single heat stress (SHS).@*METHODS@#We randomly assigned 32 C57 male mice to an SHS (n = 16) and a control group (n = 16), the former bathed in water at 43 ℃ and the latter at 25 ℃ for 15 minutes. At 1 and 7 days after exposure, we harvested the testicular tissue for observation of the morphological changes of testicular cells by HE staining and determination of the location and expression of the PGAM1 protein by immunohistochemistry and Western blot.@*RESULTS@#The testis volume of the mice were reduced significantly, the spermatogenic tubules were disorganized, and the cells were reduced in number after heat stress and basically disappeared after 7 days. Immunohistochemistry showed extensive expression of the PGAM1 protein in the testicular spermatogenic tubules of the SHS-exposed mice, significantly higher than in the control group at 1 day after exposure, which was down-regulated in the testis tissue at 7 days, but still markedly higher than that in the control. Western blot exhibited significantly up-regulated expression of the PGAM1 protein after heat stress compared with that in the control group.@*CONCLUSIONS@#The expression of the PGAM1 protein undergoes dynamic changes in the mouse testis after exposed to single heat stress, which is related to heat stress-induced proliferation and division of testicular spermatogenic cells.
Subject(s)
Animals , Male , Mice , Heat-Shock Response , Phosphoglycerate Mutase , TestisABSTRACT
Phosphoglycerate mutase 1 (PGAM1) is upregulated in many cancer types and involved in cell proliferation, migration, invasion, and apoptosis. However, the relationship between PGAM1 and prostate cancer is poorly understood. The present study investigated the changes in PGAM1 expression in prostate cancer tissues compared with normal prostate tissues and examined the cellular function of PGAM1 and its relationship with clinicopathological variables. Immunohistochemistry and Western blotting revealed that PGAM1 expression was upregulated in prostate cancer tissues and cell lines. PGAM1 expression was associated with Gleason score (P = 0.01) and T-stage (P = 0.009). Knockdown of PGAM1 by siRNA in PC-3 and 22Rv1 prostate cancer cell lines inhibited cell proliferation, migration, and invasion and enhanced cancer cell apoptosis. In a nude mouse xenograft model, PGAM1 knockdown markedly suppressed tumor growth. Deletion of PGAM1 resulted in decreased expression of Bcl-2, enhanced expression of Bax, caspases-3 and inhibition of MMP-2 and MMP-9 expression. Our results indicate that PGAM1 may play an important role in prostate cancer progression and aggressiveness, and that it might be a valuable marker of poor prognosis and a potential therapeutic target for prostate cancer.
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Phosphoglycerate mutase 1 (PGAM1) as one of the most important enzymes for glycolysis pathway,is highly expressed in multiple tumor tissues and negatively correlated with the prognosis of cancer patients.PGAM1 catalyzes the conversion of 3-phosphoglycerate (3-PG) to 2-phosphoglycerate (2-PG) in glycolysis pathway,then promoting anabolic pathways,energy generation,and maintaining redox balance during cancer cell proliferation and metastasis.The small molecule PGAM1 inhibitors have emerged as a promising strategy for anti-tumor therapy.In this review,the significance of PGAM1 in tumor was reviewed and the research progress of PGAM1 inhibitors was also introduced.
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Phosphoglycerate mutase 1 (PGAM1) as one of the most important enzymes for glycolysis pathway, is highly expressed in multiple tumor tissues and negatively correlated with the prognosis of cancer patients. PGAM1 catalyzes the conversion of 3-phosphoglycerate (3-PG) to 2-phosphoglycerate (2-PG) in glycolysis pathway, then promoting anabolic pathways, energy generation, and maintaining redox balance during cancer cell proliferation and metastasis. The small molecule PGAM1 inhibitors have emerged as a promising strategy for anti-tumor therapy. In this review, the significance of PGAM1 in tumor was reviewed and the research progress of PGAM1 inhibitors was also introduced.
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Necroptosis, or programmed cell death, is a type of cell death with a controllable death signaling pathway and the morphological features similar to necrosis.It is mainly mediated by death receptors or pathogen pattern re-cognition receptors.Among them, tumor necrosis factor receptor 1 (TNFR1)-mediated necroptosis is the most well-studied one.Receptor-interacting protein kinase 1 (RIPK1) and receptor-interacting protein kinase 3 (RIPK3) are the 2 key kina-ses involved in the formation of complex I & II and necrosome in the process of necroptosis.Phosphoglycerate mutase 5 ( PGAM5) , a member of phosphoglycerate mutase gene family, lacks PGAM activity and possesses the phosphatase activi-ty.PGAM5 is anchored in the mitochondrial membrane and is also called mitochondrial phosphoglycerate mutase 5.It has been shown that PGAM5 involves in the formation of necrosome during necroptosis and it is able to accelerate the fission of mitochondria by dephosphorylation of dynamin-related protein 1 (DRP1), thus promoting cell necroptosis.
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PURPOSE: To evaluate whether factors related to lipid and glucose metabolism have a potential role in the progression of prostate cancer, we measured the mRNA levels of the peroxisome proliferator-activated receptor (PPAR), fatty acid elongase (ELOVL), and two glycolytic enzymes in prostate cancer (CaP) tissues. MATERIALS AND METHODS: Prostate tissues, obtained from radical prostatectomy (n=10) and transurethral resection of prostate (n=18), were quickly frozen in liquid nitrogen for RNA measurements. Transcript signals of PPAR alpha, PPAR gamma, ELOVL2, ELOVL5, phosphoglycerate kinase 1 (PgK1) and phosphoglycerate mutase 2 (PgM2) were measured using a reverse-transcription polymerase chain reaction. RESULTS: The transcript signals of PPAR alpha and PPAR gamma were down-regulated in CaP tissues. In addition, the mRNA level of PgM2 in CaP tissues was lower than that in benign prostatic hyperplasia (BPH) tissues. However, the messages for ELOVL2, ELOVL5, and PgK1 were not significantly changed. CONCLUSIONS: These results suggest that lowering of the PPARalpha, PPARgamma and PgM2 messages may be involved in aberrant and uncontrolled prostate cell growth and differentiation.
Subject(s)
Down-Regulation , Glucose , Metabolism , Nitrogen , Peroxisome Proliferator-Activated Receptors , Peroxisomes , Phosphoglycerate Kinase , Phosphoglycerate Mutase , Polymerase Chain Reaction , PPAR alpha , PPAR gamma , Prostate , Prostatectomy , Prostatic Hyperplasia , Prostatic Neoplasms , RNA , RNA, Messenger , Transurethral Resection of ProstateABSTRACT
Bacillus megaterium accumulated 3-phosphoglycerate during sporulation which was utilized during spore germination. During sporulation a protein was synthesized before or at the start of 3-phosphoglycerate accumulation inside the developing spores about 1.5 h before dipicolinic acid accumulation. This protein has an affinity for Mn2+ and other divalent metal ions and inhibits phosphoglycerate mutase activity which has been shown to require Mn2+ However, the levels of the inhibitor decreased considerably (75-85%) during spore germination. No appreciable amount of the inhibitor was detected in the vegetable cell and mother cell compartment; however, the forespore compartment possesses an activity comparable to that of dormant spores. The partially purified inhibitor has a molecular weight of 11,000 and possesses both high and low affinity binding sites for Mn2+ and Ca2+ as determined by Scatchard plot analysis.