OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)...OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)mice(WT)were fed with normal diet(0.4%NaCl)or high salt diet(4%NaCl),separately for 6 weeks.In the rescue study,one week of hydrochlorothiazide or saline injection were treated with the CKO mice fed high salt diet.The blood pressure,biochemical indexes,and the expression of small intestinal sodium transporters(NHE3,NKCC1,eNaC)was detected.The organ injury markers(MMP2/MMP9)and the histopathological changes of kidneys were observed,whereas the changes of duodenal sodium absorption were detected by small intestinal perfusion in vivo.RESULTS The CCKBR^(fl/fl)villin-Cre mice with high salt intake exhibited high blood pressure,increased duodenal sodium absorption and urinary sodium excretion,and with renal injury.The protein expression of NHE3,NKCC1 and eNaC were also significant increase in the intestine of CKO-HS mice.Treatment with hydrochlorothiazide remarkably attenuated the elevated blood pressure by high salt absorption in the CCKBR^(fl/fl)villin-Cre mice,but no significant histopathological changes were observed.CONCLUSIONS These results support a crucial role of intestinal Cckbr deficiency on SSH development and the diuretic antihypertension effect in CCKBR^(fl/fl)villin-Cre mice.The CCKBR^(fl/fl)villin-Cre mice with the high salt intake may serve as a stable model of salt-sensitive hypertensive induced by sodium overloading.展开更多
BACKGROUND Left ventricular noncompaction(LVNC) is an increasingly recognised cardiomyopathy of which a significant percentage are genetic in origin. The purpose of the present study was to identify potential pathogen...BACKGROUND Left ventricular noncompaction(LVNC) is an increasingly recognised cardiomyopathy of which a significant percentage are genetic in origin. The purpose of the present study was to identify potential pathogenic mutation leading to disease in a Chinese LVNC family.METHODS A 3-generation family affected by LVNC was recruited. Clinical assessments were performed on available family members, with clinical examination, ECG, echocardiography and cardiac MRI. The proband(Ⅰ-2), the proband’s daughter(Ⅱ-1, affected) and mother(Ⅲ-1, unaffected) were selected for WGS. Sanger sequencing were performed in all of the 4 surviving family members.RESULTS Combined whole genome sequencing with linkage analysis identified a novel missense mutation in the giant protein obscurin(OBSCN NM_001098623, c.C19063T), as the only plausible disease-causing variant that segregates with disease among the four surviving individuals, with interrogation of the entire genome excluding other potential causes. This c.C19063T missense mutation resulted in p.R6355W in the encoded OBSCN protein. It affected a highly conserved residue in the C terminus of the obscurin-B-like isoform between the PH and STKc domains, which was predicted to affect the function of the protein by different bioinformatics tools.CONCLUSIONS Here we present clinical and genetic evidence implicating the novel R6355W missense mutation in obscurin as the cause of familial LVNC. This expands the spectrum of obscurin’s roles in cardiomyopathies. It furthermore highlights that rare obscurin missense variants, currently often ignored or left uninterpreted, should be considered to be relevant for cardiomyopathies and can be identified by the approach presented here. This study also provided new insights into the molecular basis of OBSCN mutation positive LVNC.展开更多
基金This study is funded by the CAMS Innovation Fund for Medical Sciences(CIFMS,2022-I2M-C&T-A-010)the National Natural Science Foundation(China)(81970358).
文摘OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)mice(WT)were fed with normal diet(0.4%NaCl)or high salt diet(4%NaCl),separately for 6 weeks.In the rescue study,one week of hydrochlorothiazide or saline injection were treated with the CKO mice fed high salt diet.The blood pressure,biochemical indexes,and the expression of small intestinal sodium transporters(NHE3,NKCC1,eNaC)was detected.The organ injury markers(MMP2/MMP9)and the histopathological changes of kidneys were observed,whereas the changes of duodenal sodium absorption were detected by small intestinal perfusion in vivo.RESULTS The CCKBR^(fl/fl)villin-Cre mice with high salt intake exhibited high blood pressure,increased duodenal sodium absorption and urinary sodium excretion,and with renal injury.The protein expression of NHE3,NKCC1 and eNaC were also significant increase in the intestine of CKO-HS mice.Treatment with hydrochlorothiazide remarkably attenuated the elevated blood pressure by high salt absorption in the CCKBR^(fl/fl)villin-Cre mice,but no significant histopathological changes were observed.CONCLUSIONS These results support a crucial role of intestinal Cckbr deficiency on SSH development and the diuretic antihypertension effect in CCKBR^(fl/fl)villin-Cre mice.The CCKBR^(fl/fl)villin-Cre mice with the high salt intake may serve as a stable model of salt-sensitive hypertensive induced by sodium overloading.
基金supported by the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences (2019XK320057)the National Key Research and Development Program of China (2016YFC1300100)+1 种基金the Clinical Transformation and Transformation Fund of the Chinese Academy of Medical Sciences (2019XK320058)the National Natural Science Foundation of China (81974042)
文摘BACKGROUND Left ventricular noncompaction(LVNC) is an increasingly recognised cardiomyopathy of which a significant percentage are genetic in origin. The purpose of the present study was to identify potential pathogenic mutation leading to disease in a Chinese LVNC family.METHODS A 3-generation family affected by LVNC was recruited. Clinical assessments were performed on available family members, with clinical examination, ECG, echocardiography and cardiac MRI. The proband(Ⅰ-2), the proband’s daughter(Ⅱ-1, affected) and mother(Ⅲ-1, unaffected) were selected for WGS. Sanger sequencing were performed in all of the 4 surviving family members.RESULTS Combined whole genome sequencing with linkage analysis identified a novel missense mutation in the giant protein obscurin(OBSCN NM_001098623, c.C19063T), as the only plausible disease-causing variant that segregates with disease among the four surviving individuals, with interrogation of the entire genome excluding other potential causes. This c.C19063T missense mutation resulted in p.R6355W in the encoded OBSCN protein. It affected a highly conserved residue in the C terminus of the obscurin-B-like isoform between the PH and STKc domains, which was predicted to affect the function of the protein by different bioinformatics tools.CONCLUSIONS Here we present clinical and genetic evidence implicating the novel R6355W missense mutation in obscurin as the cause of familial LVNC. This expands the spectrum of obscurin’s roles in cardiomyopathies. It furthermore highlights that rare obscurin missense variants, currently often ignored or left uninterpreted, should be considered to be relevant for cardiomyopathies and can be identified by the approach presented here. This study also provided new insights into the molecular basis of OBSCN mutation positive LVNC.
