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...
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.
Objective To observe the molecular genetic characteristics of seven Chinese families with Leberprime;s hereditary optic neuropathy (LHON). Methods Ophthalmologic examinations were performed on seven probands, maternal members from seven Chinese families and 134 healthy controls. There were two LHON patients in seven Chinese families except probands. The entire mitochondrial genome was amplified using 24 pairs of oligonucleotide primers with overlapping fragments.The mutational site was analyzed through comparison of the Results and Cambridge reference sequence. The penetrance of mutation site was calculated and the haplotype was analyzed. Results Molecular analysis of mitochondrial DNA (mtDNA) in these pedigrees revealed the absence of three common LHON associated with ND4 G11778A, ND1 G3460A and ND6 T14484C mutations. The ND1 T3394C mutation in probands and other matrilineal relatives was present in four out of 134 Chinese healthy controls. Strikingly, these families exhibited very low penetrance of visual impairment. The penetrance was 12.50%, 22.22%, 16.76%, 6.25%, 9.09%, 11.11% and 28.57%. The Results of phylogenetic tree analysis of submitochondrial haplotype showed that these mtDNA polymorphism sites belong to the Asian haplogroups M9, M9, M, D4, M, M9 and M9. Conclusions T3394C mutation exists in seven Chinese LHON pedigrees, and the penetrance was ranged from 6.25% to 28.57%. The patients have different clinical manifestations.
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.
Objective To investigate the spectrum of mitochondrial DNA (mtDNA) mutations in Chinese patients with Leber′s hereditary optic neuropathy (LHON). Methods The primary mtDNA mutations (G3460A、G11778A and T14484 C) of 140 patients with LHON were detected by mutation-specific priming polymerase chain reaction (MSP-PCR), heteroduplex-single strand conformation polymorphism polymerase chain reaction (HA-SSCP), restriction fragment length polymorphisms (RFLP) and measurement of DNA sequence. The transmissibility of the patients′ stirps was analyzed.Results In the 140 patients with LHON, G11778A mtDNA primary mutation was found in 130 (92.9%), including 113 males and 17 females; G3460A mutation was found in 2 (1.4%) including 1 male and 1 female; G14484A mutation was found in 8 (5.7% ) including 6 males and 2 females.Conclusion In Chinese patients with LHON, the incidence of G11778A mtDNA mutation is higher than that of G3460A and T14484C. (Chin J Ocul Fundus Dis，2003，19：269-332)
Objective To analyze the new primary mutation in Chinese people with Leberprime;s hereditary optic neuropathy (LHON). Methods Genomic DNA was collected from 260 suspected LHON patients and 100 normal healthy persons. The mitochondria DNA mutation at nucleotide position (NP) 15257 and the hot spot (14452-14601 bp) of ND6 gene which include the mutations at NP (14482, 14498, 14568, 14596, 14495, and 14459) were screened by using polymerase chain reaction (PCR), heteroduplex-single strand conformation polymorphism (HA-SSCP) and restriction fragment length polymorphism (RFLP) analysis and sequencing. Primary mutation spectrum of Chinese race was analyzed. Results Eight kinds of polymorphism of mitochondria DNA were found in 260 suspected LHON patients and 100 normal healthy persons, including NP 14488C, 14518G, and 14617G which hadnrsquo;t been reported (http://www.mitomap.org/). No mutation at NP 15257, 14482, 14498, 14568, 14596, 14495, and 14459 was found. Conclusion The NP 15257A may not be the primary mutation in Chinese. Because of the race difference, 14452-14601 bp in ND6 gene may not be the hot spot in Chinese patients with LHON, and other hot spots may exist. (Chin J Ocul Fundus Dis, 2006, 22: 82-85)