2.4E-BP1 counteracts human mesenchymal stem cell senescence via maintaining mitochondrial homeostasis.
Yifang HE ; Qianzhao JI ; Zeming WU ; Yusheng CAI ; Jian YIN ; Yiyuan ZHANG ; Sheng ZHANG ; Xiaoqian LIU ; Weiqi ZHANG ; Guang-Hui LIU ; Si WANG ; Moshi SONG ; Jing QU
Protein & Cell 2023;14(3):202-216
Although the mTOR-4E-BP1 signaling pathway is implicated in aging and aging-related disorders, the role of 4E-BP1 in regulating human stem cell homeostasis remains largely unknown. Here, we report that the expression of 4E-BP1 decreases along with the senescence of human mesenchymal stem cells (hMSCs). Genetic inactivation of 4E-BP1 in hMSCs compromises mitochondrial respiration, increases mitochondrial reactive oxygen species (ROS) production, and accelerates cellular senescence. Mechanistically, the absence of 4E-BP1 destabilizes proteins in mitochondrial respiration complexes, especially several key subunits of complex III including UQCRC2. Ectopic expression of 4E-BP1 attenuates mitochondrial abnormalities and alleviates cellular senescence in 4E-BP1-deficient hMSCs as well as in physiologically aged hMSCs. These f indings together demonstrate that 4E-BP1 functions as a geroprotector to mitigate human stem cell senescence and maintain mitochondrial homeostasis, particularly for the mitochondrial respiration complex III, thus providing a new potential target to counteract human stem cell senescence.
Mesenchymal Stem Cells/physiology*
;
Cellular Senescence
;
Homeostasis
;
Cell Cycle Proteins/metabolism*
;
Adaptor Proteins, Signal Transducing/metabolism*
;
Mitochondria/metabolism*
;
Electron Transport Complex III/metabolism*
;
Humans
;
Cells, Cultured
3.<i>BCS1i>Neonatal growth retardation and lactic acidosis initiated by novel mutation sites in <i>Li> gene.
Ming WANG ; Dong Juan WANG ; Yi SHU ; Dan ZHU ; Chao Wen YU ; Xiao Yan HE ; Lin ZOU
Chinese Journal of Preventive Medicine 2023;57(6):912-917
This study aims to analyze the clinical characteristics and genetic variations of two cases with developmental delay and lactic acidosis in a family, and to explore the relationship between genetic variations and clinical features. A retrospective analysis was conducted on the clinical characteristics of two siblings with developmental delay and lactic acidosis who were treated at the Neonatal Department of Children's Hospital of Chongqing Medical University in May 2019 and December 2021, respectively. Whole-exome sequencing was used to detect genetic variations in the affected children. Homology modeling of the BCS1L protein was performed to analyze the structural and functional changes of the protein. The correlation between genetic variations and clinical phenotypes was analyzed. The results showed that the main clinical features of the two affected children in this family were manifestations of mitochondrial respiratory chain complex Ⅲ deficiency, including prematurity, developmental delay, respiratory failure, lactic acidosis, cholestasis, liver dysfunction, renal tubular lesions, coagulation dysfunction, anemia, hypoglycemia, hypotonia, and early death. Whole-exome sequencing revealed a novel deletion mutation c.486_488delGGA (p.E163del) and a novel missense mutation c.992C>T (p.T331I) in the BCS1L gene. Structural analysis of the homology modeling showed that the compound heterozygous mutation had a significant impact on protein function. In conclusion, the novel mutation site c.992C>T (p.T331I) in the BCS1L gene is a "likely pathogenic" mutation, and the compound heterozygous mutation is closely related to the phenotype of mitochondrial respiratory chain complex Ⅲ deficiency.
Humans
;
Acidosis, Lactic/genetics*
;
Electron Transport Complex III/genetics*
;
Retrospective Studies
;
Mutation
;
Growth Disorders
;
ATPases Associated with Diverse Cellular Activities/genetics*
4.Reassessing the six months prognosis of patients with severe or very severe aplastic anemia without hematological responses at three months after immunosuppressive therapy.
Xiang Rong HU ; Xin ZHAO ; Li ZHANG ; Li Ping JING ; Wen Rui YANG ; Yuan LI ; Lei YE ; Kang ZHOU ; Jian Ping LI ; Guang Xin PENG ; Hui Hui FAN ; Yang LI ; Yang YANG ; You Zhen XIONG ; Feng Kui ZHANG
Chinese Journal of Hematology 2022;43(5):393-399
Objective: To reassess the predictors for response at 6 months in patients with severe or very severe aplastic anemia (SAA/VSAA) who failed to respond to immunosuppressive therapy (IST) at 3 months. Methods: We retrospectively analyzed the clinical data of 173 patients with SAA/VSAA from 2017 to 2018 who received IST and were classified as nonresponders at 3 months. Univariate and multivariate logistic regression analysis were used to evaluate factors that could predict the response at 6 months. Results: Univariate analysis showed that the 3-month hemoglobin (HGB) level (<i>Pi>=0.017) , platelet (PLT) level (<i>Pi>=0.005) , absolute reticulocyte count (ARC) (<i>Pi><0.001) , trough cyclosporine concentration (CsA-C0) (<i>Pi>=0.042) , soluble transferrin receptor (sTfR) level (<i>Pi>=0.003) , improved value of reticulocyte count (ARC(△)) (<i>Pi><0.001) , and improved value of soluble transferrin receptor (sTfR(△)) level (<i>Pi><0.001) were related to the 6-month response. The results of the multivariate analysis showed that the PLT level (<i>Pi>=0.020) and ARC(△) (<i>Pi><0.001) were independent prognostic factors for response at 6 months. If the ARC(△) was less than 6.9×10(9)/L, the 6-month hematological response rate was low, regardless of the patient's PLT count. Survival analysis showed that both the 3-year overall survival (OS) [ (80.1±3.9) % <i>vsi> (97.6±2.6) %, <i>Pi>=0.002] and 3-year event-free survival (EFS) [ (31.4±4.5) % <i>vsi> (86.5±5.3) %, <i>Pi><0.001] of the nonresponders at 6 months were significantly lower than those of the response group. Conclusion: Residual hematopoietic indicators at 3 months after IST are prognostic parameters. The improved value of the reticulocyte count could reflect whether the bone marrow hematopoiesis is recovering and the degree of recovery. A second treatment could be performed sooner for patients with a very low ARC(△).
Anemia, Aplastic/drug therapy*
;
Antilymphocyte Serum/therapeutic use*
;
Cyclosporine/therapeutic use*
;
Humans
;
Immunosuppression Therapy
;
Immunosuppressive Agents/therapeutic use*
;
Prognosis
;
Receptors, Transferrin/therapeutic use*
;
Retrospective Studies
;
Treatment Outcome
5.Analysis of gene variant in an infant with succinic semialdehyde dehydrogenase deficiency.
Dandan YAN ; Xiaowei XU ; Xuetao WANG ; Xinjie ZHANG ; Xiufang ZHI ; Hong WANG ; Yuqing ZHANG ; Jianbo SHU
Chinese Journal of Medical Genetics 2022;39(2):216-221
OBJECTIVE:
To explore the genetic basis for a child with succinate semialdehyde dehydrogenase deficiency.
METHODS:
Peripheral blood samples of the proband and his parents were collected and subjected to Sanger sequencing. High-throughput sequencing was used to verify the gene variants. Bioinformatic software was used to analyze the pathogenicity of the variant sites.
RESULTS:
Sanger sequencing showed that the proband carried a homozygous c.1529C>T (p.S510F) variant of the ALDH5A1 gene, for which his mother was a carrier. The same variant was not detected in his father. However, high-throughput sequencing revealed that the child and his father both had a deletion of ALDH5A1 gene fragment (chr6: 24 403 265-24 566 986).
CONCLUSION
The c.1529C>T variant of the ALDH5A1 gene and deletion of ALDH5A1 gene fragment probably underlay the disease in the child. High-throughput sequencing can detect site variation as well as deletion of gene fragment, which has enabled genetic diagnosis and counseling for the family.
Amino Acid Metabolism, Inborn Errors/genetics*
;
Child
;
Developmental Disabilities
;
Humans
;
Infant
;
Mutation
;
Succinate-Semialdehyde Dehydrogenase/genetics*
6.Research Progress of Abnormal Iron Metabolism and Tumor of Lymphatic Hematopoiesis System --Review.
Journal of Experimental Hematology 2022;30(4):1277-1280
Iron metabolism is the process of absorption, transport, storage and conversion and excretion of the essential trace element iron in living organisms. Normal iron metabolism tightly regulates iron content at the systemic and cellular levels through a variety of related proteins to prevent excessive free radicals from being generated during the iron cycle that can damage the body. Various abnormalities in iron metabolism are found in a variety of lymphohaematopoietic tumours and an insidious link between iron metabolism and tumour development has been revealed. Serum ferritin levels and abnormalities of iron transport proteins, transferrin and their receptors can be used as prognostic indicators for lymphohematopoietic tumours and have opened up new directions of diagnosis and treatment, with a large number of novel drugs targeting tumours emerging to date. This article briefly describes the normal iron metabolism process and highlights the progress of research on abnormal iron metabolism in lymphohematopoietic tumors at the systemic and cellular levels.
Hematopoiesis
;
Humans
;
Iron/metabolism*
;
Neoplasms
;
Receptors, Transferrin/metabolism*
;
Transferrin/metabolism*
7.Succinate dehydrogenase-deficient renal cell carcinoma:a clinicopathological, ultrastructural and molecular analysis.
Xiao Tong WANG ; Xuan WANG ; Ru Song ZHANG ; Kai CHENG ; Qiu Yuan XIA ; Qiu RAO
Chinese Journal of Pathology 2022;51(1):12-16
Objective: To investigate the clinicopathological features, immunophenotype, ultrastructure, genetic alterations and prognosis of succinate dehydrogenase-deficient renal cell carcinoma (SDH RCC). Methods: A total of 11 SDH RCCs, diagnosed from 2010 to 2019, were selected from the Department of Pathology of Nanjing Jingling Hospital, Nanjing University School of Medicine for clinicopathologic, immunohistochemical (IHC), ultrastructural investigation and follow-up. The molecular features of seven cases were analyzed by the panel-targeted DNA next generation sequencing (NGS). Results: There were seven males and four females, with ages ranging from 24 to 62 years (mean 41.4 years, median 41 years). Microscopically, SDH RCC was mainly composed of solid and tubular structures with local cystic change. Four cases showed nested or trabecular structure distributed in a loose hypocellular connective tissue or around scar, similar to oncocytoma. The neoplastic cells demonstrated flocculent eosinophilic cytoplasm with typical intracytoplasmic vacuoles. Immunohistochemically, eight cases were negative for SDHB; three cases showed focal and weak expression, whereas normal renal tubular and vascular endothelial cells demonstrated strong cytoplasmic staining. NGS of DNA targeted-panel detected pathogenic mutations of SDHB gene in seven cases (including three cases with equivocal IHC expression of SDHB), without any mutations in other SDH related genes. There were four cases of SDHB missense mutation, one case of frameshift mutation, one case of splicing mutation, and one case of acquired stop codon mutation. Conclusions: SDH RCC is a distinct variant of RCCs with genetic tendency or with hereditary cancer syndrome. NGS is recommended to detect the related gene mutations for a definitive diagnosis. The patients should be closely followed up.
Adult
;
Carcinoma, Renal Cell/genetics*
;
Endothelial Cells
;
Female
;
Humans
;
Kidney Neoplasms/genetics*
;
Male
;
Middle Aged
;
Prognosis
;
Succinate Dehydrogenase/genetics*
;
Young Adult
9.Compound heterozygous NDUFS1 variants identified in a Chinese pedigree affected with mitochondrial respiratory chain complex I deficiency.
Chao GAO ; Baiyun CHEN ; Yang GAO ; Huichun ZHANG ; Liye SHI ; Weimeng LI ; Haibei LI ; Jiaojiao HUANG
Chinese Journal of Medical Genetics 2021;38(3):247-250
OBJECTIVE:
To explore the genetic basis for a Chinese pedigree with suspected mitochondrial functional defects through combined next-generation sequencing (NGS), copy number variation sequencing (CNV-seq), and mitochondrial DNA (mtDNA) sequencing.
METHODS:
Clinical data of the proband and his family members were collected. The patient and his parents were subjected to family-trio whole-exome sequencing (WES), CNV-seq and mtDNA variant detection. Candidate variant was verified by Sanger sequencing.
RESULTS:
Trio-WES revealed that the proband has carried compound heterozygous variants of the NDUFS1 gene, including a paternally derived c.64C>T (p.R22X) nonsense variant and a maternally derived c.845A>G (p.N282S) missense variant. Both variants may cause loss of protein function. No variant that may cause the phenotype was identified by CNV-seq and mtDNA variant analysis.
CONCLUSION
Children with suspected mitochondrial disorders may have no specific syndromes or laboratory findings. A comprehensive strategy including mtDNA testing may facilitate the diagnosis and early clinical interventions.
Child
;
China
;
DNA Copy Number Variations
;
Electron Transport
;
Humans
;
Mutation
;
NADH Dehydrogenase/genetics*
;
Pedigree
10.Relationship between Cardiac Geometry and Serum Hepcidin in Chronic Kidney Disease: Analysis from the KNOW-CKD Study
Hyang Ki MIN ; Yun Kyu OH ; Kyu Hun CHOI ; Kyu Beck LEE ; Sue K PARK ; Curie AHN ; Sung Woo LEE
Journal of Korean Medical Science 2020;35(1):2-
1,897 patients in a large-scale multicenter prospective Korean study. Logistic regression analysis was used to identify the relationship between cardiac function and geometry and serum hepcidin levels.RESULTS: The mean relative wall thickness (RWT) and left ventricular mass index (LVMI) were 0.38 and 42.0 g/m2.7, respectively. The mean ejection fraction (EF) and early diastolic mitral inflow to annulus velocity ratio (E/e′) were 64.1% and 9.9, respectively. Although EF and E/e′ were not associated with high serum hepcidin, RWT and LVMI were significantly associated with high serum hepcidin levels in univariate logistic regression analysis. In multivariate logistic regression analysis after adjusting for variables related to anemia, bone mineral metabolism, comorbidities, and inflammation, however, only each 0.1-unit increase in RWT was associated with increased odds of high serum hepcidin (odds ratio, 1.989; 95% confidence interval, 1.358–2.916; P < 0.001). In the subgroup analysis, the independent relationship between RWT and high serum hepcidin level was valid only in women and patients with low transferrin saturation (TSAT).CONCLUSION: Although the relationship was not cause-and-effect, increased RWT was independently associated with high serum hepcidin, particularly in women and patients with low TSAT. The relationship between cardiac geometry and serum hepcidin in CKD patients needs to be confirmed in future studies.]]>
Anemia
;
Comorbidity
;
Female
;
Hepcidins
;
Humans
;
Inflammation
;
Logistic Models
;
Metabolism
;
Miners
;
Prospective Studies
;
Renal Insufficiency, Chronic
;
Transferrin

Result Analysis
Print
Save
E-mail