Augmenter of liver regeneration (ALR) is a newly discovered cytokine that can promote liver regeneration and proliferation of damaged liver cells. In the renal tissue, ALR is mainly expressed in the cytoplasm of the medullary loops, collecting ducts and distal convoluted tubules in the renal medulla, and is low in the glomerular and cortical tubules. Various stimulation, such as ischemiacal, hypoxia, poisoning and inflammatory stimulation, can induce the expression of ALR in the epithelial cells of proximal tubule regeneration and the damaged areas of cortex, and participate in the repair process. Current studies have found that in acute kidney injury (AKI), exogenous ALR can protect renal tubular epithelial cells by inhibiting apoptosis of renal tubular epithelial cells, promoting proliferation of renal tubular epithelial cells, inhibiting the activities of inflammatory cells, and promoting the reduction of renal injury. This paper intends to review the basic characteristics of ALR and the pathogenesis of AKI, summarize the characteristics of the mechanism of ALR in AKI by combing the relevant literature on ALR and AKI in recent years, and provide knowledge reserve and direction reference for the in-depth study of ALR in kidney in the future.
Mitochondrial quality control includes mechanisms such as mitochondria-derived vesicles, fusion / fission and autophagy. These processes rely on the collaboration of a variety of key proteins in the inner and outer membranes of mitochondria to jointly regulate the morphological structure and functional integrity of mitochondria, repair mitochondrial damage, and maintain the homeostasis of their internal environment. The imbalance of mitochondrial quality control is associated with leukemia. Therefore, by exploring the mechanisms related to mitochondrial quality control of various leukemia cells and their interactions with immune cells and immune microenvironment, this article sought possible targets in the treatment of leukemia, providing new ideas for the immunotherapy of leukemia.
Objective\ To study the mechanism of myocardial protection of exogenous creatine phosphate (CP) against ischemia reperfused injury in modified isolated perfused working rat heart model.\ Methods\ Seventy two rats were divided into five groups.The rat hearts of five groups undergone Langendorff perfused were arrested and made totally ischemic for 40 minutes at 37℃ and reperfused for 20 minutes. St.Thomas cardioplegic solution wasn’t used in group A;It was used immediately after ischemia in group B and grou...
ObjectiveTo investigate the expression of mitochondrial transcription factor A (TFAM) in colon cancer and the effect of its expression on proliferation of colon cancer cell. MethodsThirty cases of colon cancer in the First Affiliated Hospital of Sun Yat-sen University from March 2013 to April 2013 were studied. TFAM mRNA was detected both in colon cancer tissue and para-cancer tissue by real-time PCR. TFAM mRNA and protein were detected in normal colon cell strain and colon cancer strains SW480, HT-29, and HCT116 by real-time PCR and Western blot, respectively. The proliferation of SW480 cells was evaluated after up-regulating TFAM. ResultsThe expression of TFAM mRNA in the colon cancer tissue was significantly higher than that in the para-cancer tissue (P < 0.000 1). The expressions of TFAM mRNA were obviously increased in the SW480, HT-29, and HCT116 cells as compared with the normal colon cell strain (P value was 0.000 8, 0.002 3, and 0.000 6, respectively), among which the most notable increase was detected in the SW480 cells. The expressions of TFAM protein were obviously increased in the SW480, HT-29, and HCT116 cells as compared with the normal colon cell strain (P value was 0.000 2, 0.003 8, and 0.001 6, respectively), among which the most notable increase was detected in the SW480 cells. After up-regulating TFAM by plasmid transfection, the proliferation of the pcDNA3.1-TFAM-SW480 cell was increased significantly as compared with the pcDNA3.1-SW480 cell at 96 h and 120 h after transfection by the MTT test (P < 0.000 1). The proliferation of the pcDNA3.1-TFAM-SW480 cell was increased significantly as compared with the pcDNA3.1-SW480 cell at 48 h after transfection by the BrdU test (P < 0.001 0). ConclusionTFAM expression is high in colon cancer. Up-regulated TFAM could promote the proliferation of colon cancer cells.
Leber hereditary optic neuropathy (LHON) is a blinding disease caused by mutations in mitochondrial DNA. It is a classic disease model for studying mitochondrial abnormalities. Its main mutation sites are m11778G.A, m.3460G.A and m.14484T.C. LHON cell models are mainly produced by lymphoblasts, fibroblasts, cell hybrids and induced pluripotent stem cells, while LHON animal models are mainly mice, which are produced by rotenone and ND4 mutants. Although the research on the LHON model has achieved good results, there are still many difficulties in constructing an ideal experimental model, which severely limit the exploring to the pathogenesis and therapeutic drugs of LHON. A detailed understanding of the application and characteristics of existing models in LHON will help improve experimental design and construct new models.
ObjectiveMitochondrial encephalomyopathy is a series of diseases that drag in central nervous system and generalized muscles. The pathogenesis of the disease is lack of ATP for the dysfunction of mitochondria. The misdiagnosis rate of the disease is high and the purpose of this study is to improve the recognition and diagnosis of mitochondrial encephalomyopathy and thus, clinicians could take rational treatment in time and improve patients' prognosis. MethodsThe clinical data of 11 patients with mitochondrial encephalomyopathy were analyzed including the physical data, clinical presentations, laboratory data, neuroimaging findings, muscle biopsy, genetic testing, treatment and prognosis. Reviewing literature and summarizing the clinical characteristics of mitochondrial encephalomyopathy. ResultsAmong the 11 patients with mitochondrial encephalomyopathy, the mean age was 17 years old. 1 case had family history. 7 cases were misdiagnosed in the first clinic visit. The onset of the 11 cases, 9 were paroxysmal and 2 were hidden. In the course, 10 cases had an epileptic seizure. Among the 9 cases who took the determination of serum lactate, 8 was in high level.9 cases had MRI examination and all found abnormality, 10 patients had EEG examination, and 9 cases found abnormality, 6 cases had muscle biopsy and all found the ragged red fiber(RRF). 6 cases had molecular genetic testing, and all found mutations in mitochondrial DNA. Among the 10 cases who had epileptic seizure, 3 cases can be controlled with single kind of antiepileptic drug. The other 7 cases had a recurrence of epilepsy with single kind of antiepileptic drugs, but can be cotrolled after drug adjusting or drug combination. ConclusionMitochondrial encephalomyopathy is often accompanied by seizure, which is usually found in children, and also often accompanied by systemic muscle symptoms. The clinical manifestations of the disease is not typical, but is complex and varied symptoms, so the clinical misdiagnosis rate is high. Mitochondrial encephalomyopathy mainly involves the main intracranial artery distribution area (parietal lobe, temporal lobe, occipital lobe, etc.) in central nervous system, and can involve more than one part. Patients with mitochondrial myopathy brain are usually detected the elevation of serum lactate levels, but if the lactic acid level is normal, it does not rule out the possibility of the disease, the confirmation of the disease is mainly by muscle biopsy or genetic tests. There is no specific treatment for mitochondrial encephalomyopathy till now, and it still give priority to symptomatic treatment. And the prognosis is poorer.
Objective To investigate the effect of S-adenosylmethionine (SAM) on mitochondrial injury that was induced by ischemia-reperfusion in rat liver. Methods Fifty-four rats were randomly divided equally into 3 groups: control group, ischemia-reperfusion group (I/R group), and SAM-treated group (SAM group). Hepatic ischemia had been only lasted for 30 min by obstructing the blood stream of hepatic portal vena (the portal vena was only separated but not obstructed in control group). The rats of SAM group received SAM intraperitoneally 2 h prior to ischemia. Blood samples of each group were collected from the inferior cava vena at 0, 1 and 6 h after reperfusion and the serum levels of AST and ALT were detected. Mitochondrial super oxidedismutase (SOD), malondialdehyde (MDA), adenosine triphosphate (ATP) and energy charge (EC) in samples of liver tissue were detected, and the mitochondrial ultrastructure was observed with electronmicroscope. Results The serum levels of AST, ALT and mitochondrial MDA at 0, 1 and 6 h after reperfusion in the I/R group were significantly higher than those in the control group, whereas the levels of mitochondrial SOD, ATP and EC were significantly lower than those in the control group (P＜0.01). Except the value of 0 h, when it comes to SAM group, the levels of AST, ALT and mitochondrial MDA were significantly lower (P＜0.05) and the levels of mitochondrial SOD, ATP and EC were significantly higher (P＜0.05, P＜0.01) than those in the I/R group, respectively. The mitochondrial ultrastructure was injured obviously in I/R group when compared with that in control group. The number of mitochondria decreased and the mitochondria swelled, making the crista became obscure and the density of matrix became lower. The above changes in SAM group were less obvious when compared with those in I/R group. Conclusion SAM may protect mitochondrion against hepatic ischemia injury, since it may prevent mitochondrial lipid peroxidation, increase ATP, and eventually improve energy metabolism after ischemia-reperfusion.
Leber’s hereditary optic neuropathy (LHON) is a paradigm maternal hereditary eye disease, mainly involving the retinal and macular fibers of the optic disc in the anterior ethmoid plate of the sclera. LHON has the characteristics of sex bias among males and incomplete penetrance. Primary mitochondrial DNA mutations m.11778G>A, m. 14484T>C, m.3460G>A are the molecular basis of LHON. However, other risk factors, such as secondary mitochondrial DNA mutations, mitochondrial haplotypes, nuclear modification genes, estrogen, vitamin B12 and environmental factors, work together to affect its phenotypic expression. The clinical diagnosis of LHON mainly limited to the detection of the primary mutation site of mitochondrial DNA. Therefore, comprehensive analysis of multiple risk factors of LHON will facilitate to construct multi-dimensional model of prevention, diagnosis and treatment system, which provide accurate and individualized medical services for patients. These may alleviate the incidence in LHON families. It also provides new ideas and different angles for the in-depth study of the pathogenesis of LHON.
RCBTB1 gene associated hereditary retinopathy is an extremely rare inherited retinal disease (IRD) discovered recently. The mutation of RCBTB1 gene can lead to a variety of IRD clinical phenotypes, such as early retinitis pigmentosa and delayed chorioretinal atrophy. The hereditary mode of RCBTB1 gene associated retinopathy is autosomal recessive. RCBTB1 gene plays an important role in maintaining mitochondrial function and anti-oxidative stress defense mechanism of retinal pigment epithelium cells. In the future, it is necessary to further determine whether there is a genotypic and phenotypic correlation in the age of onset of RCBTB1 gene associated retinopathy or multi-organ involvement, and evaluate the safety and efficacy of adeno-associated virus-mediated RCBTB1 gene replacement therapy in animal models, to explore the feasibility of gene replacement therapy and stem cell therapy.
Objective To investigate the role of mitochondrial adenosine triphosphatesensitive potassium channel(mitoKATP) in immature myocardial ischemic preconditioning, and to provide evidence for immature myocardial protection. Methods Langendorff isolated heart infused model was used in the experiment. Twentyfour rabbits (aged from 14 to 21 days) were randomly divided into 4 groups：ischemiareperfusion group（I/R group）, myocardial ischemic preconditioning group(E1 group), 5hydroxydecanoate(5-HD) group (E2 group) and Diazoxide (Diaz) group(E3 group). Hemodynamics recovery rate, myocardial water content(MWC), the leakage rates of serum creatine kinase and lactate dehydrogenase, adenosine triphosphate content, superoxide dismutase activity, malondialdehyde content, myocardial cell Ca2+ content and myocardial mitochondrial Ca2+ content, myocardial mitochondrial Ca2+-ATPase activity, the adenosine triphosphate(ATP) synthesizing ability of myocardial mitochondria were tested, and myocardial ultrastructure was observed via electron microscopy. Results The hemodynamics recovery rate, myocardial water content(P＜0.05), adenosine triphosphate content, superoxide dismutase activity, myocardial mitochondrial Ca2+-adenosine triphosphyatase(ATPase) activity and the ATP synthesizing ability of myocardial mitochondria of the rabbits in E1 and E3 group were significantly better than that in I/R group and E2 group(P＜0.05). Malondialdehyde content, the leakage rates of serum creatine kinase and lactate dehydrogenase, myocardial cell Ca2+ content and myocardial mitochondrial Ca2+ content of the rabbits in E1 group and E3 group were significantly lower than that in I/R group and E2 group (P＜0.05). The myocardial ultrastructure injury in E1 and E3 group were significantly reduced compared with that in I/R and E2 group. Conclusion Myocardial ischemic preconditioning has significant protective effects on immature myocardium. Its mechanism may be related to the activation of mitoKATP.