Objective To investigate the preventive and therapeutic effects and the mechanisms of pyrrol idine dithiocarbamate (PDTC) on the atrophy of denervated skeletal muscle. Methods Thirty adult Wistar rats of either gender, weighing (200 ± 10) g were randomly divided into 3 groups: group A (n=6, control group), group B (n=12, denervation group), and group C (n=12, PDTC treatment group). The sciatic nerves of the rats were only exposed without cutting off in group A, and the rats were made denervated gastrocnemius models in groups B and C. PDTC of 100 mg/(kg•d) was injected peritoneally in group C and an intraperitoneal injection of the same amount normal sal ine was given in group B. After 14 and 28 days, the gastrocnemius was harvested to measure the ratio of muscle wet weight; the levels of nuclear factor of κB (NF-κB)p65 protein and the opening of the mitochondrial permeabil ity transition pore (MPTP) in the gastrocnemius were detectedrespectively by Western blot and laser confocal scanning microscope; and the apoptotic cells in atrophic muscle were measured with TUNEL. Results The ratio of muscle wet weight in group A was 1.039 ± 0.115, and it significantly decreased in groups B and C (P lt; 0.05); after 14 and 28 days of operation, the ratio of muscle wet weight in group C significantly increased when compared with those in group B (P lt; 0.05). The expression of NF-κB p65 protein in group A was 0.224 ± 0.041; the expressions of NF-κB p65 in groups B and C significantly increased when compared with that in group A (P lt; 0.05); however, the expression of NF-κB p65 in group C was significantly lower than that in group B (P lt; 0.05). The MPTP fluorescence intensity in group A was 31.582 ± 1.754; the MPTP fluorescence intensity was significantly lower in groups B and C than in group A (P lt; 0.05), and the MPTP fluorescence intensity in group C was significantly higher than that in group B (P lt; 0.05). The rate of apoptosis in group A was 4.542% ± 0.722%; after 14 and 28 days of operation, the rates of apoptosis significantly increased when compared groups B and C with group A, and signiticantly decreased when compared group C with group B (P lt; 0.05). Conclusion PDTC can retard denervated skeletal muscle atrophy, and the effect may have a relationship with its inhibition on NF-κB, the opening of the MPTP, and the ratio of apoptosis.
Purpose To investigate mitochondrial DNA (mt-DNA) mutations in optic neuritis of unknow reason (ONUR) and to assess the pathogenic and differential diagnostic values of screening for mt-DNA mutations in ONUR. Method Thirty patients with ONUR were screened for mt-DNA mutations by using SSCP,mutation-specific primer PCR and sequencing. Results mt-DNA mutations were found in 12 out of the thirty patients.All of the mutations were at 11778 position,but no one at 3460 and 15257. Conclusions Quite a number of patients (12/30,40%) with ONUR were caused actually by mt-DNA mutation.Screening for mt-DNA mutation in these patients has a pathogenic and differential diagnostic significance. (Chin J Ocul Fundus Dis,2000,16:78-79)
目的:应用心肌自发荧光(AF)研究心肌线粒体氧化代谢状态,监测线粒体功能改变的早期信号。方法:烟酰胺腺嘌呤(磷酸)二核苷酸[NAD(P)H]作为荧光探针,用光谱分辨的时间相关单光子计数(TCSPC)记录375nm紫外激光激发的心肌AF光谱和荧光寿命,测试影响线粒体呼吸时AF动态衰减。结果:在420~560nm光谱区域,至少需用3个荧光寿命池0.4~0.7ns,1.2~1.9ns和8.0~13.0ns描述细胞AF。线粒体呼吸阻断剂鱼藤酮可显著增加AF强度,缩短平均荧光寿命。氧化磷酸化解偶联剂二硝基酚可显著降低AF强度,在520nm处增宽荧光光谱,延长平均荧光寿命。这些结果和NADH荧光动力学离体实验(in vitro)有可比性。结论:光谱分辨的荧光寿命技术测定心肌NAD(P)H荧光有很好的重复性,在细胞水平上增加了心肌氧化代谢或线粒体功能障碍的知识,为临床诊断和治疗线粒体功能障碍开拓了新视野。
Objective To observe the retinal manifestations and classification of mitochondrial encephalomyopathy,and explore the relationship between retinopathy and systemic manifestations.Method The clinical data of 88 inpatients with mitochondrial encephalomyopathy were retrospectively analyzed,in whom 12 patients(24 eyes)with retinal manifestations who diagnosed by ophthalmology consultation and complete medical records were collected. There were nine males and three females aged from 14 to 33 years with the mean age of(20.1±7.0)years. The disease duration ranged from 2.5 to 20 years,with the mean of(9.5±6.8)years. All the patients had the eye symptoms of the different degree,such as limbs weakness,hearing decline and central nervous system symptoms. Ophthalmologic examination including best corrected visual acuity,slit lampa microscope,indirect ophthalmoscopy,noncontact Tonometer,ptosis,ocular movement,pupillary reflex and color fundus photography. Among the patients,three,one,two and five patients had undergone fundus fluorescein angiography(FFA),optical coherence tomography(OCT),lectroretinogram(ERG)and visual field examination respectively. Diabetic retinopathy were divided into “salt and pepper”, retinitis pigmentosa(RP),retinal pigment epithelium(RPE),choroidal capillary atrophy and simplex optic atrophy according to the inspection results.Results All the patients′ both eyes were involved,the disease degree of bilateral eyes was accordant. The ptosis and(or)eye movement limitation were found in nine patients(75.0%),and decreased visual acuity was in six patients(50.0%).“Salt and pepper” was found in six patients(12 eyes),presenting retinal granular pigmentation and depigmentation;the visual acuity was 0.4-1.2;no central nervous system symptoms were found in patients,such as hearing decline,twitch,ataxia and hypophrenia. RP was found in one patient(two eyes),presenting retinal cells sample pigmentation,retinal vessel shrink,optic atrophy;the vision were light perception in both eyes;hypophrenia,hearing decline,bilateral lower limbs pain and onset twitch were also found in them. RPE and choroidal capillary atrophy were found in three patients(six eyes),the choroidal great vessels and flake pigment accumulation surrounding the retina were observed;the visual acuity was hand movement0.7;limbs weakness was found in two patients;hearing decline was found in three patients;barylalia and hypophrenia were found in two patients;somnolence was found in one patient. Simplex optic atrophy was found in two patients(four eyes);the vision was 0.1-0.7;central nervous system symptoms were found in patients,such as limbs weakness,twitch,hypophrenia and headache.Conclusion Retinopathy types is concerned with visual prognosis and central nervous system symptoms.
Objective To find the new mutations of Leber's hereditary optic neuropathy (LHON). Methods Two LHON families were enrolled in this study. The probands and all maternal members in this two families were underwent ophthalmologic examinations. The ages of probands were seven and 14 years old respectively. A total of 358 healthy adults were enrolled in this study as control group. The genomic DNA from whole blood of participants were extracted. The entire mitochondrial genome of probands were PCR amplified and sequenced in 24 overlapping fragments using primers as designed. At the same time, the mtDNA of maternal relatives and 358 controls were also detected. Fourteen primate species were selected from GenBank to analyzed the phylogenetics of mitochondrial sequence. Results There was no ND4 G11778A, ND1 G3460A, ND6 T14484C mutational site in all maternal members. Molecular analysis of mtDNA in this two families identified the homoplasmic tRNAGluA14683G mutation and distinct set of variants belonging to the Asian haplogroup F1a1 and G2. The site was at theTpsi;C stem oftRNAGlu and extremely conserved among 14 primate species. It was anticipated that the A14683G increased the highly conserved C-G basepairing. Furthermore, the A14683G was absence in control group. Conclusion The tRNAGluA14683G mutation is likely a new mutation associated with LHON.
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)