The protective roles of α-lipoic acid in the rat model of mitochondrial DNA (mtDNA) 4834bp deletion in inner ear were investigated. Forty female Wistar rats at 4 weeks of age were divided into four groups: group A (D...The protective roles of α-lipoic acid in the rat model of mitochondrial DNA (mtDNA) 4834bp deletion in inner ear were investigated. Forty female Wistar rats at 4 weeks of age were divided into four groups: group A (D-galactose group, n=10), group B (D-galactose+α-lipoic acid group, n=10), group C (α-lipoic acid group, n=10), and group D (control group, n=10). Auditory brainstem response (ABR) was used to detect the hearing threshold. Colorimetry was used to analyze activity of superoxide dismutase (SOD) and concentration of malondialdehyde (MDA). The percentage of mtDNA4834bp deletion in inner ear was identified by real-time PCR. There was no significant difference in ABR threshold shift among all groups. The percentage of mtDNA4834bp deletion in group A was higher than that in other groups, but there was no significant difference in percentage of mtDNA4834bp deletion among groups B, C, and D. The activity of SOD in group A was lower than that in other groups. The concentration of MDA in group A was higher than that in other groups. It was concluded that there was no significant hearing loss when the percentage of mtDNA4834bp deletion was lower than 12.5%. α-Lipoic acid could prevent the reactive oxygen species (ROS)-induced mtDNA4834bp deletion in inner ear of rats.展开更多
Abstract Objective We identify ionizing radiation-induced mitochondrial DNA （mtDNA） deletions in human lymphocytes and their distribution in normal populations. Methods Long-range polymerase chain reactions （PCR） ...Abstract Objective We identify ionizing radiation-induced mitochondrial DNA （mtDNA） deletions in human lymphocytes and their distribution in normal populations. Methods Long-range polymerase chain reactions （PCR） using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy 6~Co y-rays. Limited-condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long-range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy ^60Co y-rays, and real-time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated. Results Two mtDNA deletions, a 7455-bp deletion （nt475-nt7929 in heavy strand） and a 9225-bp deletion （nt7714 -nt369 in heavy strand）, occurring between two 8-bp direct repeats, were identified in lymphoblastoid cells using long-range PCR, limited-condition PCR and sequencing. These results were also observed for ^60Co y-rays irradiated human peripheral blood cells. Conclusion Two novel mtDNA deletions, a 7455-bp deletion and a 9225-bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors＇ age, but was independent of gender.展开更多
Objective: To develop a simple and efficient method for detecting small populations of mitochondrial DNA deletion. Methods: Peripheral blood cell DNA was obtained from a victim who was accidently exposed to a 60Co rad...Objective: To develop a simple and efficient method for detecting small populations of mitochondrial DNA deletion. Methods: Peripheral blood cell DNA was obtained from a victim who was accidently exposed to a 60Co radiation source 11 years ago. Using the DNA as template, PCR was performed to generate multiple products including true deletions and artifacts. The full length product was recovered and used as template of secondary PCR. The suspicious deletion product of mtDNA could be confirmed if it was only yielded by first PCR. Using either original primers or their nested primers, the suspicious deletion product was amplified and authenticated as true deletion product. The template was recovered and determined to be a deletion by sequencing directly. Results: A new mtDNA deletion, spanning 889 bp from nt11688 to nt12576, was detected in the peripheral blood cells of the victim. Conclusion: The new PCR-based method is more efficient in detecting small populations of mtDNA deletion than other routine methods. MtDNA deletion is found in the victim, suggesting there is relationship between the deletion and phenotypes of the disease.展开更多
Objective: To study the 4977-bp deletion of mitochondiral DNA in lung cancer, adjacent normal tissue and health lung and its significance in the development of cancer. Methods:Thirty-seven matched lung cancer/adjacent...Objective: To study the 4977-bp deletion of mitochondiral DNA in lung cancer, adjacent normal tissue and health lung and its significance in the development of cancer. Methods:Thirty-seven matched lung cancer/adjacent histologically normal and 20 “true” normal lung tissue samples from patients without lung cancer were analyzed by long PCR technique. Results: Mitochondrial DNA 4977-bp deletion was detected in 54.1% (20/37) of lung cancers, 59.5% (22/37) of adjacent normal and 30.0% (6/30) of “true” normal lung tissues. The correlation of 4977-bp deletion with age and smoking factors was present in our data. Conclusion: Mitochondrial DNA 4977-bp deletion is not specific to lung cancer and unlikely to play an important role in carcinogenesis, and may only reflect the environmental and genetic influences during tumor progression.展开更多
OBJECTIVES: To study the status of cochlear mitochondrial DNA (mtDNA) and to determine the location of mtDNA deletion in aged mice. METHODS: We detected cochlear mtDNA in 2, 7 - 10 and 17 - 19 month old mice by nested...OBJECTIVES: To study the status of cochlear mitochondrial DNA (mtDNA) and to determine the location of mtDNA deletion in aged mice. METHODS: We detected cochlear mtDNA in 2, 7 - 10 and 17 - 19 month old mice by nested polymerase chain reaction (PCR) and DNA sequencing. RESULTS: mtDNA3867bp deletions were found in the cochleae of aged mice. The deletion occurred within nt9103-nt12970 and were flanked by 15 base pair direct repeats. Comparing the incidence of mtDNA3867bp deletions, 17 - 19 month old mice (7/8) were significantly higher than 7 - 10 month old mice (4/16). The deletion was not observed in 2 month old mice (0/7). The ratio of deleted mtDNA/total mtDNA in 17 - 19 month old mice was higher than in 7 - 10 month old mice (P展开更多
旨在研究中国广东省部分地区汉族人群线粒体DNA Region Ⅴ 9bp序列缺失情况。采用PCR-PAGE和直接测序法对3个群体144份样本mtDNA Region Ⅴ进行序列分析。结果只检测到标准型和短型(即9bp缺失)两种多态。广东汉族人群的平均缺失频率为21...旨在研究中国广东省部分地区汉族人群线粒体DNA Region Ⅴ 9bp序列缺失情况。采用PCR-PAGE和直接测序法对3个群体144份样本mtDNA Region Ⅴ进行序列分析。结果只检测到标准型和短型(即9bp缺失)两种多态。广东汉族人群的平均缺失频率为21.5%,广州、东莞和湛江汉族人群的缺失频率依次为20.8%、19.2%和25.0%。由此得出,广东汉族人群mtDNA9bp缺失频率较高,与其它地区汉族群体存在一定的差异。展开更多
应用 PCR 技术对13例神经肌肉疾病患者的线粒体 DNA 缺失进行了研究。结果表明,其中二例肢带型肌营养不良症患者的骨骼肌组织和一例帕金森氏病患者的血细胞线粒体 DNA 中存在至少526bp的缺失.提示线粒体突变在一些神经肌肉性疾病的发生...应用 PCR 技术对13例神经肌肉疾病患者的线粒体 DNA 缺失进行了研究。结果表明,其中二例肢带型肌营养不良症患者的骨骼肌组织和一例帕金森氏病患者的血细胞线粒体 DNA 中存在至少526bp的缺失.提示线粒体突变在一些神经肌肉性疾病的发生中起一定的作片用.展开更多
基金supported by grants from the State Key Program of National Natural Science of China (No. 30730094)the National Science & Technology Pillar Program during the Eleventh Five-year Plan Period (No. 2007BAI18B13)
文摘The protective roles of α-lipoic acid in the rat model of mitochondrial DNA (mtDNA) 4834bp deletion in inner ear were investigated. Forty female Wistar rats at 4 weeks of age were divided into four groups: group A (D-galactose group, n=10), group B (D-galactose+α-lipoic acid group, n=10), group C (α-lipoic acid group, n=10), and group D (control group, n=10). Auditory brainstem response (ABR) was used to detect the hearing threshold. Colorimetry was used to analyze activity of superoxide dismutase (SOD) and concentration of malondialdehyde (MDA). The percentage of mtDNA4834bp deletion in inner ear was identified by real-time PCR. There was no significant difference in ABR threshold shift among all groups. The percentage of mtDNA4834bp deletion in group A was higher than that in other groups, but there was no significant difference in percentage of mtDNA4834bp deletion among groups B, C, and D. The activity of SOD in group A was lower than that in other groups. The concentration of MDA in group A was higher than that in other groups. It was concluded that there was no significant hearing loss when the percentage of mtDNA4834bp deletion was lower than 12.5%. α-Lipoic acid could prevent the reactive oxygen species (ROS)-induced mtDNA4834bp deletion in inner ear of rats.
基金supported by the National Natural Science Foundation of China(No.30570551and No.30870749)the Beijing Natural Science Foundation(No.7053073)
文摘Abstract Objective We identify ionizing radiation-induced mitochondrial DNA （mtDNA） deletions in human lymphocytes and their distribution in normal populations. Methods Long-range polymerase chain reactions （PCR） using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy 6~Co y-rays. Limited-condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long-range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy ^60Co y-rays, and real-time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated. Results Two mtDNA deletions, a 7455-bp deletion （nt475-nt7929 in heavy strand） and a 9225-bp deletion （nt7714 -nt369 in heavy strand）, occurring between two 8-bp direct repeats, were identified in lymphoblastoid cells using long-range PCR, limited-condition PCR and sequencing. These results were also observed for ^60Co y-rays irradiated human peripheral blood cells. Conclusion Two novel mtDNA deletions, a 7455-bp deletion and a 9225-bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors＇ age, but was independent of gender.
基金Supported by the National Natural Science Foundation of China(No.30171030)
文摘Objective: To develop a simple and efficient method for detecting small populations of mitochondrial DNA deletion. Methods: Peripheral blood cell DNA was obtained from a victim who was accidently exposed to a 60Co radiation source 11 years ago. Using the DNA as template, PCR was performed to generate multiple products including true deletions and artifacts. The full length product was recovered and used as template of secondary PCR. The suspicious deletion product of mtDNA could be confirmed if it was only yielded by first PCR. Using either original primers or their nested primers, the suspicious deletion product was amplified and authenticated as true deletion product. The template was recovered and determined to be a deletion by sequencing directly. Results: A new mtDNA deletion, spanning 889 bp from nt11688 to nt12576, was detected in the peripheral blood cells of the victim. Conclusion: The new PCR-based method is more efficient in detecting small populations of mtDNA deletion than other routine methods. MtDNA deletion is found in the victim, suggesting there is relationship between the deletion and phenotypes of the disease.
文摘Objective: To study the 4977-bp deletion of mitochondiral DNA in lung cancer, adjacent normal tissue and health lung and its significance in the development of cancer. Methods:Thirty-seven matched lung cancer/adjacent histologically normal and 20 “true” normal lung tissue samples from patients without lung cancer were analyzed by long PCR technique. Results: Mitochondrial DNA 4977-bp deletion was detected in 54.1% (20/37) of lung cancers, 59.5% (22/37) of adjacent normal and 30.0% (6/30) of “true” normal lung tissues. The correlation of 4977-bp deletion with age and smoking factors was present in our data. Conclusion: Mitochondrial DNA 4977-bp deletion is not specific to lung cancer and unlikely to play an important role in carcinogenesis, and may only reflect the environmental and genetic influences during tumor progression.
基金ThisworkwassupportedbygrantsfromtheNationalOutstandingYouthSciencesFoundationofChina (No 39725026)andthePostdoctoralSciencesFoundationofChina (No [2 0 0 0 ]23)
文摘OBJECTIVES: To study the status of cochlear mitochondrial DNA (mtDNA) and to determine the location of mtDNA deletion in aged mice. METHODS: We detected cochlear mtDNA in 2, 7 - 10 and 17 - 19 month old mice by nested polymerase chain reaction (PCR) and DNA sequencing. RESULTS: mtDNA3867bp deletions were found in the cochleae of aged mice. The deletion occurred within nt9103-nt12970 and were flanked by 15 base pair direct repeats. Comparing the incidence of mtDNA3867bp deletions, 17 - 19 month old mice (7/8) were significantly higher than 7 - 10 month old mice (4/16). The deletion was not observed in 2 month old mice (0/7). The ratio of deleted mtDNA/total mtDNA in 17 - 19 month old mice was higher than in 7 - 10 month old mice (P
文摘旨在研究中国广东省部分地区汉族人群线粒体DNA Region Ⅴ 9bp序列缺失情况。采用PCR-PAGE和直接测序法对3个群体144份样本mtDNA Region Ⅴ进行序列分析。结果只检测到标准型和短型(即9bp缺失)两种多态。广东汉族人群的平均缺失频率为21.5%,广州、东莞和湛江汉族人群的缺失频率依次为20.8%、19.2%和25.0%。由此得出,广东汉族人群mtDNA9bp缺失频率较高,与其它地区汉族群体存在一定的差异。
