Mitochondrial DNA mutations in focal segmental glomerular sclerotic lesions

局灶节段性肾小球硬化病变中的线粒体 DNA 突变

• 批准号: 13671097
• 负责人: YAMAGATA Kunihiro
• 金额: $ 2.24万
• 依托单位: UNIVERSITY OF TSUKUBA
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13671097/
• 关键词: Focal and segmental glomerular sclerosis (FGS); glomerular epithelial cells; Glomerulonephritis; Mitochondrial DNA; glomerular sclerosis; IgA nephropathy; Heteroplasmy; 膜性腎症

Glomerular epithelial cells (GEpC) are primary pathogenic sites in focal segmental glomerular sclerosis (FGS) lesions. GEpCs are regarded as terminally differentiated cells and do not proliferate. This characteristic is the same for neuron cells and muscular cells, which are major sites of mtDNA mutations accumulation. We screened for mitochondrial DNA (mtDNA) mutations in renal biopsy specimens from primary FGS patients and also from IgA nephropathy patients as a secondary FGS subject and as a control. MtDNA extracted from kidney biopsy specimens was amplified with appropriate primer pairs for studying mtDNA point mutations 3243 A to G, 3271 T to C, 8344 A to G, 8993 T to G, C and the common deletion (a 4977-bp deletion spanning mtDNA nucleotide pairs 8469 to 13447). In situ amplification of both total mtDNA and the common deletion were also performed. Two patients with FGS had a 3243 A to G point mutation and 12 patients with FGS, and 7 patients with IgA nephropathy accompanied by glomerular sclerotic lesions, had the common deletion in their kidney tissue. No patient showed mtDNA mutations 3271 T to C, 8344 A to G or 8993 T to G or C. The degree of heteroplasmy for 3243 A to G point mutation was more than 85%, however, the heteroplasmy for the common deletion was less than 1%. Using in situ PCR, normal mtDNA was mainly distributed to the tubular epithelium, and mtDNA with the common deletion was mainly distributed among GEpC. In conclusion, it is suggested that mtDNA mutations are distributed to the GEpC in some patients with primary FGS and secondary FGS with IgA nephropathy. These mutations may be related to GEpC damage.

肾小球上皮细胞（GEpC）是局灶节段性肾小球硬化（FGS）病变的主要致病部位。GepC被认为是终末分化的细胞，并且不增殖。神经细胞和肌肉细胞也具有同样的特征，它们是线粒体DNA突变积累的主要场所。我们在原发性FGS患者和继发性FGS患者伊加肾病患者的肾活检标本中筛选线粒体DNA（mtDNA）突变，并作为对照。用合适的引物对从肾活检标本中提取的mtDNA进行扩增，以研究mtDNA点突变3243 A至G，3271 T至C，8344 A至G，8993 T至G，C和常见缺失（跨越mtDNA核苷酸对8469至13447的4977-bp缺失）。同时进行了线粒体总DNA和常见缺失的原位扩增。2例FGS患者的肾组织中存在3243 A → G点突变，12例FGS患者和7例伴有肾小球硬化的伊加肾病患者的肾组织中存在共同缺失。没有患者显示mtDNA 3271 T至C、8344 A至G或8993 T至G或C突变。3243 A → G点突变的异质性大于85%，而共同缺失的异质性小于1%。原位PCR结果显示，正常mtDNA主要分布于肾小管上皮细胞，缺失mtDNA主要分布于GepC细胞。结论：在原发性FGS和继发性FGS伴伊加肾病患者中，线粒体DNA突变分布于GEpC。这些突变可能与GEpC损伤有关。

项目成果

Yamagata K, Takahashi H, Tomida C, Yamagata Y, Koyama A: "Prognosis of asymptomatic hematuria and/or proteinuria in men. : High prevalence of IgA nephropathy among proteinuric patients found in mass screening"Nephron. 91・1. 34-42 (2002)

Yamagata K、Takahashi H、Tomida C、Yamagata Y、Koyama A：“男性无症状血尿和/或蛋白尿的预后。：大规模筛查中发现 IgA 肾病的高患病率”Nephron 91・1。 (2002)

Hirayama K, Ebihara I, Yamamoto S, Kai H, Muro K, Yamagata K, Kobayashi M, Koyama A: "Predominance of type 2 immune response in idiopathic membranous nephropathy : cytoplasmic cytokine analysis"Nephron. 91・2. 255-261 (2002)

Hirayama K、Ebihara I、Yamamoto S、Kai H、Muro K、Yamagata K、Kobayashi M、Koyama A：“特发性膜性肾病中 2 型免疫反应的优势：细胞质细胞因子分析”Nephron 91・2。 2002）

Yamagata K, Muro K, Usui J, Hagiwara M, Kai H, Arakawa Y, Shimizu Y, Tomida C, Hirayama K, Kobayashi M, Koyama A: "Mitochondrial DNA mutations in focal segmental glomerulosclerosis lesions"J Am Soc Nephrol. 13・7. 1816-1823 (2002)

Yamagata K、Muro K、Usui J、Hagiwara M、Kai H、Arakawa Y、Shimizu Y、Tomida C、Hirayama K、Kobayashi M、Koyama A：“局灶性节段性肾小球硬化病变中的线粒体 DNA 突变”J Am Soc Nephrol 13。 7. 1816-1823 (2002)

Yamagata K, Koyama A 他: "Involvement of mitochondria in glomerular sclerotic lesions"J Am Soc Nephrol. 13・9. A370 (2002)

Yamagata K、Koyama A 等：“肾小球硬化病变中线粒体的参与”J Am Soc Nephrol 13・9。

Yamagata K. et al.: "Accumulation of Mitochondrial DNA Mutations in Renal Epithelium in FSGS patients"J Am Soc Nephrol. 12(9). 130A (2001)

Yamagata K. 等人：“FSGS 患者肾上皮中线粒体 DNA 突变的累积”J Am Soc Nephrol。