Objective: To investigate the protective effect of dulaglutide on lipopolysaccharide (LPS)-induced inju- ry in MLE-12 cells. Methods: An in vitro model of acute lung injury was established by inducing MLE-12 cells with LPS ( 1 μg/mL) , followed by treatment with dulaglutide for 24 hours. The cells were divided into four groups : CON group , LPS group , LPS + 100 nmol/L dulaglutide group , and LPS + 200 nmol/L dulaglutide group. Protein and RNA were extracted from each group. The mRNA levels of inflammatory factors , including interleukin (IL)-6 , tumor necrosis factor-α (TNF-α ) , IL-1β , monocyte chemotactic protein 1 (CCL2) , C-X-C motif chemokine lig- and (CXCL) 1 and CXCL2 , were detected by qRT-PCR. Cell apoptosis was assessed by TUNEL assay , and the expression levels of phosphorylated protein kinase B (P-Akt) and phosphorylated extracellular signal-regulated ki- nase (P-Erk) were measured by Western blot. Results: Compared with the CON group , the LPS group showed in- creased mRNA levels of inflammatory mediators (TNF-α , IL-6 , IL-1β , CCL2 , CXCL1 , and CXCL2) , increased TUNEL-positive cells , and elevated expression of P-Akt and P-Erk proteins. Compared with the LPS group , the LPS + 100 nmol/L dulaglutide treatment group exhibited reduced mRNA levels of TNF-α , IL-6 , IL-1β , CCL2 , CXCL1 , and CXCL2 , decreased TUNEL-positive cells , and downregulated expression of P-Akt and P-Erk pro- teins. However, the LPS + 200 nmol/L dulaglutide treatment group showed less pronounced improvement in inflam- matory factors compared to the LPS + 100 nmol/L dulaglutide group. Conclusion Dulaglutide has a protective effect on LPS-induced injury in MLE-12 cells , potentially through inhibiting Akt and Erk phosphorylation , thereby reducing the expression of inflammatory mediators and alleviating inflammatory damage , ultimately protecting the lungs.

Objective:To investigate the associations between MRI texture features and genetic mutations in clear cell renal cell carcinoma (ccRCC) and non-ccRCC (n-ccRCC).Methods:This was a cross-section study. A retrospective review was performed on 31 patients (ccRCC group 19 cases and n-ccRCC group 12 cases) diagnosed with renal cell carcinomas and underwent targeted sequencing between April 2011 and December 2021 in the Third Affiliated Hospital of Soochow University. All the patients underwent MRI examinations within two weeks before partial or radical nephrectomy. Texture features were extracted from T 1WI, T 2WI, Dixon-MRI, cortical-medulla phase (CMP), nephrographic phase (NGP), and delayed phase (DEP) images. MRI texture features with the highest value for distinguishing ccRCC from n-ccRCC were selected for subsequent analysis. The next-generation high-throughput sequencing technology was employed to analyze gene mutations in renal tumors. The correlation between mutation genes and texture features in ccRCC and n-ccRCC was analyzed using Spearman correlation coefficient. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation analysis was performed. Results:A total of 8 MRI texture features were selected. In the ccRCC group, PTEN mutation was correlated with DEP_InverseDifferenceMoment_angle0_offset7 ( r=-0.58, P=0.009). In the non-ccRCC group, SETD2 mutation was correlated with CM_Phase_InverseDifferenceMoment_AllDirection_offset1 and Dixon_W_InverseDifferenceMoment_AllDirection_offset7 ( r=0.58, 0.63, P=0.048, 0.027), PBRM1 mutation was correlated with DE_Phase_InverseDifferenceMoment_angle0_offset7 and DE_Phase_HaraVariance ( r=0.61, -0.60, P=0.034, 0.039), and FAT1 mutation was correlated with DE_Phase_HaraVariance and NG_Phase_Inertia_angle135_offset4 ( r=0.58, 0.58, P=0.047, 0.047). The KEGG pathway annotation analysis showed that the mechanisms of the mutation genes that correlated with MRI texture features in the ccRCC group were related to the p53 signaling pathway, inositol phosphate metabolism, central carbon metabolism in cancer, EGFR tyrosine kinase inhibitor resistance, PD-L1 expression and PD-1 checkpoint pathway in cancer, and phosphatidylinositol signaling system. The mutation genes correlated with MRI texture features in the non-ccRCC group were mainly associated with lysine degradation. Conclusion:The associations are found between MRI texture features and underlying genetic mutations of ccRCC and n-ccRCC. These mutation genes have completely different enrichment pathways.

Objective:To explore the value of four-dimensional flow (4D Flow) MRI in evaluating hemodynamic changes of transplant renal artery stenosis (TRAS).Methods:The study was a cross-sectional study. A retrospective analysis of 67 patients after renal transplantation was performed in Third Affiliated Hospital of Soochow University from January 2021 to October 2022. All patients were examined with non-contrast enhanced magnetic resonance angiography (NCE-MRA) and 4D Flow MRI. After NCE-MRA assessment, the patients were divided into a non stenosis group (39 cases), non-obvious stenosis group (stenosis degree<50%, 13 cases) and obvious stenosis group (stenosis degree≥50%, 15 cases). The 4D Flow MRI data were analyzed using the post-processing software CVI42 (Canada) to measure hemodynamic parameters of the transplanted renal artery in the non-stenosis group, as well as the proximal, central, and distal regions of the stenosis in the non-obvious stenosis group and obvious stenosis group. The parameters included net flow rate, maximum flow rate, average velocity, peak velocity, average wall shear stress, and maximum wall shear stress. One way analysis of variance and least significant difference (LSD) were used to test the differences of hemodynamic parameters among the three groups and between the proximal, central and distal regions of the stenosis. Pearson correlation coefficient was used to evaluate the correlation between hemodynamic parameters of transplant renal artery and estimated glomerular filtration rate (eGFR).Results:The net flow, maximum flow and average velocity at the proximal region of stenosis in the group with obvious stenosis of transplanted renal artery were significantly lower than those in the non-stenosis group and the non-obvious stenosis group (all P<0.05). The net flow and maximum flow at the distal region of stenosis in both obvious stenosis group and non-obvious stenosis group were lower than those in non-stenosis group, and the differences were statistically significant (both P<0.001). The mean velocity and peak velocity at the distal region of stenosis in the obvious stenosis group were higher than those in the non-stenosis group, and the differences were statistically significant (both P<0.05). The maximum and average wall shear stress at the distal region of stenosis in the obvious stenosis group were lower than those in the non-stenosis group and the non-obvious stenosis group, and the differences were statistically significant (both P<0.05). The net flow and maximum flow in the center region of stenosis were lower than those in the proximal region of stenosis, and the differences were statistically significant (both P<0.05). The peak velocity in the center region and distal region of stenosis was higher than those in the proximal region of stenosis, and the difference was statistically significant (both P<0.05). There was a positive correlation between the net flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.270, 0.260, 0.320, respectively, P=0.044, 0.041, 0.036, respectively). There was a positive correlation between the maximum flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.306, 0.276, 0.269, respectively, P=0.037, 0.041, 0.043, respectively). Conclusion:After TRAS, there is a significant change in blood flow status. The 4D Flow MRI can provide quantitative hemodynamic parameters to reflect the hemodynamic changes of TRAS.

Objective:To explore the correlation between renal function and abdominal aortic hemodynamic parameters based on four-dimensional flow(4D Flow) MRI in patients with chronic kidney disease (CKD).Methods:A cross-section prospective study was conducted on 73 patients diagnosed with CKD at First People′s Hospital of Changzhou between March 2021 and May 2023, as well as 13 volunteers without kidney injury. According to the estimated glomerular filtration rate (eGFR), the subjects were divided into CKD 1-3 stage group ( n=34), CKD 4-5 stage group ( n=39), and control group ( n=13). All subjects underwent 4D Flow MRI examination of the abdominal aorta, measuring pulse wave velocity (PWV), peak velocity, and maximum wall shear stress (WSS) at the proximal plane (Plane_1) and the higher renal artery opening plane (Plane_2) of the abdominal aorta. The differences in 4D Flow MRI hemodynamic parameters among the three groups were compared using a one-way analysis of variance or the Kruskal-Wallis test. The correlation between 4D Flow MRI hemodynamic parameters and eGFR was analyzed by using the Spearman correlation coefficient. The independent influencing factors that affect eGFR were analyzed by using multivariate linear regression analysis. Results:There were significant differences in abdominal aortic PWV and maximal WSS of Plane_1 and Plane_2 among the three groups ( H=10.38, P=0.006; F=11.16, P<0.001; F=4.75, P=0.011). There were no significant differences in the peak velocity of Plane_1 and Plane_2 among the three groups (both P>0.05). Abdominal aortic PWV was negatively correlated with eGFR ( r s=-0.30, P=0.005). There was a positive correlation between the maximal WSS of Plane_1 and Plane_2 with eGFR ( r s=0.39, P<0.001; r s=0.29, P=0.006). Abdominal aortic PWV and maximal WSS of Plane_1 were independent influencing factors of eGFR (b=-4.32, P=0.018; b=132.23, P=0.004). Conclusions:There is an independent correlation between renal function and abdominal aortic hemodynamic parameters based on 4D Flow MRI in patients with CKD, and abdominal aortic PWV and maximal WSS of Plane_1 were independent influencing factors of eGFR.

Objective:To investigate the disease burden, clinical characteristics and independent risk factors affecting in-hospital outcomes of children with congenital heart disease (CHD) combined with heart failure (HF) in China.Methods:(1) Descriptive study: based on the global burden of disease study 2021, available data on children under 15 years of age with CHD and HF in China from 1990 to 2021 were collected. The prevalence and trends in different age subgroups (<1 year, 1-<2 years, 2-<5 years, 5-<10 years, 10-<15 years) were analyzed, and the annual percentage change (EAPC) was estimated using linear regression. (2) Retrospective cohort study: a total of 1 062 children with CHD and HF from a multicenter study on pediatric HF in China were included. The children were divided into two groups:<2 years group and 2-<18 years group. Data on demographics, clinical features, diagnosis, treatments, and in-hospital outcomes were analyzed. Mann-Whitney U test and chi-square test were used for group comparisons.Multivariable Logistic regression was applied to identify factors influencing outcomes (in-hospital mortality and adverse cardiovascular events). Results:(1) From 1990 to 2021, the number of children with CHD and HF in China increased from 333 000 (95% uncertainty interval ( UI) 271 000-405 000) to 368 000 (95% UI 296 000-459 000), a growth of 10.8% (95% UI 5.0%-16.6%). Concurrently the prevalence rate increased from 104.5 (95% UI 85.1-127.3) per 100 000 to 142.0 (95% UI 114.0-176.8) per 100 000, a growth of 35.9% (95% UI 28.7%-43.0%), with an EAPC of 1.5% (95% CI 1.2%-1.8%). Although the number of cases in the<1 year and 1-<2 years groups decreased by 41.0% and 25.6%, respectively, the prevalence in all age groups showed an upward trend:<1 year EAPC 0.6% (95% CI 0.5%-0.7%); 1-<2 years EAPC 0.9% (95% CI 0.8%-1.0%); 2-<5 years EAPC 1.2% (95% CI 1.0%-1.4%); 5-<10 years EAPC 1.5% (95% CI 1.2%-1.8%); 10-<15 years EAPC 2.1% (95% CI 1.9%-2.3%). (2) The multicenter study revealed that among 1 062 hospitalized children, 528 (49.7%) were male and 534 (50.3%) were female, with the age at admission of 5.4 (2.2,18.2) months. The majority of the children (77.9%, 827/1 062) were under 2 years of age, whereas 22.1% (235/1 062) were aged between 2-<18 years. Children with complex congenital heart defects accounted for the highest proportion (48.6%, 516/1 062), while those with isolated CHD made up 31.5% (335/1 062). Statistically significant differences were observed in several variables in demographics, clinical features, diagnosis, treatments, and outcomes between the two age groups (all P<0.05). The use of renin-angiotensin-aldosterone system inhibitors (41.1%, 436/1 062) and beta-blockers (8.7%, 92/1 062) was lower in hospitalized children with CHD and HF. Logistic regression identified complex CHD ( OR=7.73, 95% CI 2.24-26.63; OR=3.17, 95% CI 1.92-5.23), pulmonary hyperperfusion ( OR=2.15, 95% CI 1.01-4.18; OR=2.00, 95% CI 1.35-2.97), left ventricular ejection fraction<55% ( OR=2.13, 95% CI 1.08-4.21; OR=2.80, 95% CI 1.45-5.56), arterial oxygen partial pressure ( OR=0.99, 95% CI 0.98-0.99; OR=0.99, 95% CI 0.98-0.99), and serum calcium levels ( OR=0.31, 95% CI 0.17-0.58; OR=0.42, 95% CI 0.28-0.62) as independent risk factors for in-hospital mortality and cardiovascular events. Conclusions:The disease burden of CHD combined with HF in China has shown a continuous upward trend from 1990 to 2021, with higher growth rates in older age groups. Complex CHD, pulmonary hyperperfusion, left ventricular ejection fraction <55%, arterial oxygen partial pressure, and serum calcium concentration are independent risk factors for in-hospital mortality and cardiovascular events.

Objective:To investigate the disease burden, clinical characteristics and independent risk factors affecting in-hospital outcomes of children with congenital heart disease (CHD) combined with heart failure (HF) in China.Methods:(1) Descriptive study: based on the global burden of disease study 2021, available data on children under 15 years of age with CHD and HF in China from 1990 to 2021 were collected. The prevalence and trends in different age subgroups (<1 year, 1-<2 years, 2-<5 years, 5-<10 years, 10-<15 years) were analyzed, and the annual percentage change (EAPC) was estimated using linear regression. (2) Retrospective cohort study: a total of 1 062 children with CHD and HF from a multicenter study on pediatric HF in China were included. The children were divided into two groups:<2 years group and 2-<18 years group. Data on demographics, clinical features, diagnosis, treatments, and in-hospital outcomes were analyzed. Mann-Whitney U test and chi-square test were used for group comparisons.Multivariable Logistic regression was applied to identify factors influencing outcomes (in-hospital mortality and adverse cardiovascular events). Results:(1) From 1990 to 2021, the number of children with CHD and HF in China increased from 333 000 (95% uncertainty interval ( UI) 271 000-405 000) to 368 000 (95% UI 296 000-459 000), a growth of 10.8% (95% UI 5.0%-16.6%). Concurrently the prevalence rate increased from 104.5 (95% UI 85.1-127.3) per 100 000 to 142.0 (95% UI 114.0-176.8) per 100 000, a growth of 35.9% (95% UI 28.7%-43.0%), with an EAPC of 1.5% (95% CI 1.2%-1.8%). Although the number of cases in the<1 year and 1-<2 years groups decreased by 41.0% and 25.6%, respectively, the prevalence in all age groups showed an upward trend:<1 year EAPC 0.6% (95% CI 0.5%-0.7%); 1-<2 years EAPC 0.9% (95% CI 0.8%-1.0%); 2-<5 years EAPC 1.2% (95% CI 1.0%-1.4%); 5-<10 years EAPC 1.5% (95% CI 1.2%-1.8%); 10-<15 years EAPC 2.1% (95% CI 1.9%-2.3%). (2) The multicenter study revealed that among 1 062 hospitalized children, 528 (49.7%) were male and 534 (50.3%) were female, with the age at admission of 5.4 (2.2,18.2) months. The majority of the children (77.9%, 827/1 062) were under 2 years of age, whereas 22.1% (235/1 062) were aged between 2-<18 years. Children with complex congenital heart defects accounted for the highest proportion (48.6%, 516/1 062), while those with isolated CHD made up 31.5% (335/1 062). Statistically significant differences were observed in several variables in demographics, clinical features, diagnosis, treatments, and outcomes between the two age groups (all P<0.05). The use of renin-angiotensin-aldosterone system inhibitors (41.1%, 436/1 062) and beta-blockers (8.7%, 92/1 062) was lower in hospitalized children with CHD and HF. Logistic regression identified complex CHD ( OR=7.73, 95% CI 2.24-26.63; OR=3.17, 95% CI 1.92-5.23), pulmonary hyperperfusion ( OR=2.15, 95% CI 1.01-4.18; OR=2.00, 95% CI 1.35-2.97), left ventricular ejection fraction<55% ( OR=2.13, 95% CI 1.08-4.21; OR=2.80, 95% CI 1.45-5.56), arterial oxygen partial pressure ( OR=0.99, 95% CI 0.98-0.99; OR=0.99, 95% CI 0.98-0.99), and serum calcium levels ( OR=0.31, 95% CI 0.17-0.58; OR=0.42, 95% CI 0.28-0.62) as independent risk factors for in-hospital mortality and cardiovascular events. Conclusions:The disease burden of CHD combined with HF in China has shown a continuous upward trend from 1990 to 2021, with higher growth rates in older age groups. Complex CHD, pulmonary hyperperfusion, left ventricular ejection fraction <55%, arterial oxygen partial pressure, and serum calcium concentration are independent risk factors for in-hospital mortality and cardiovascular events.

Objective:To investigate the associations between MRI texture features and genetic mutations in clear cell renal cell carcinoma (ccRCC) and non-ccRCC (n-ccRCC).Methods:This was a cross-section study. A retrospective review was performed on 31 patients (ccRCC group 19 cases and n-ccRCC group 12 cases) diagnosed with renal cell carcinomas and underwent targeted sequencing between April 2011 and December 2021 in the Third Affiliated Hospital of Soochow University. All the patients underwent MRI examinations within two weeks before partial or radical nephrectomy. Texture features were extracted from T 1WI, T 2WI, Dixon-MRI, cortical-medulla phase (CMP), nephrographic phase (NGP), and delayed phase (DEP) images. MRI texture features with the highest value for distinguishing ccRCC from n-ccRCC were selected for subsequent analysis. The next-generation high-throughput sequencing technology was employed to analyze gene mutations in renal tumors. The correlation between mutation genes and texture features in ccRCC and n-ccRCC was analyzed using Spearman correlation coefficient. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation analysis was performed. Results:A total of 8 MRI texture features were selected. In the ccRCC group, PTEN mutation was correlated with DEP_InverseDifferenceMoment_angle0_offset7 ( r=-0.58, P=0.009). In the non-ccRCC group, SETD2 mutation was correlated with CM_Phase_InverseDifferenceMoment_AllDirection_offset1 and Dixon_W_InverseDifferenceMoment_AllDirection_offset7 ( r=0.58, 0.63, P=0.048, 0.027), PBRM1 mutation was correlated with DE_Phase_InverseDifferenceMoment_angle0_offset7 and DE_Phase_HaraVariance ( r=0.61, -0.60, P=0.034, 0.039), and FAT1 mutation was correlated with DE_Phase_HaraVariance and NG_Phase_Inertia_angle135_offset4 ( r=0.58, 0.58, P=0.047, 0.047). The KEGG pathway annotation analysis showed that the mechanisms of the mutation genes that correlated with MRI texture features in the ccRCC group were related to the p53 signaling pathway, inositol phosphate metabolism, central carbon metabolism in cancer, EGFR tyrosine kinase inhibitor resistance, PD-L1 expression and PD-1 checkpoint pathway in cancer, and phosphatidylinositol signaling system. The mutation genes correlated with MRI texture features in the non-ccRCC group were mainly associated with lysine degradation. Conclusion:The associations are found between MRI texture features and underlying genetic mutations of ccRCC and n-ccRCC. These mutation genes have completely different enrichment pathways.

Objective:To explore the value of four-dimensional flow (4D Flow) MRI in evaluating hemodynamic changes of transplant renal artery stenosis (TRAS).Methods:The study was a cross-sectional study. A retrospective analysis of 67 patients after renal transplantation was performed in Third Affiliated Hospital of Soochow University from January 2021 to October 2022. All patients were examined with non-contrast enhanced magnetic resonance angiography (NCE-MRA) and 4D Flow MRI. After NCE-MRA assessment, the patients were divided into a non stenosis group (39 cases), non-obvious stenosis group (stenosis degree<50%, 13 cases) and obvious stenosis group (stenosis degree≥50%, 15 cases). The 4D Flow MRI data were analyzed using the post-processing software CVI42 (Canada) to measure hemodynamic parameters of the transplanted renal artery in the non-stenosis group, as well as the proximal, central, and distal regions of the stenosis in the non-obvious stenosis group and obvious stenosis group. The parameters included net flow rate, maximum flow rate, average velocity, peak velocity, average wall shear stress, and maximum wall shear stress. One way analysis of variance and least significant difference (LSD) were used to test the differences of hemodynamic parameters among the three groups and between the proximal, central and distal regions of the stenosis. Pearson correlation coefficient was used to evaluate the correlation between hemodynamic parameters of transplant renal artery and estimated glomerular filtration rate (eGFR).Results:The net flow, maximum flow and average velocity at the proximal region of stenosis in the group with obvious stenosis of transplanted renal artery were significantly lower than those in the non-stenosis group and the non-obvious stenosis group (all P<0.05). The net flow and maximum flow at the distal region of stenosis in both obvious stenosis group and non-obvious stenosis group were lower than those in non-stenosis group, and the differences were statistically significant (both P<0.001). The mean velocity and peak velocity at the distal region of stenosis in the obvious stenosis group were higher than those in the non-stenosis group, and the differences were statistically significant (both P<0.05). The maximum and average wall shear stress at the distal region of stenosis in the obvious stenosis group were lower than those in the non-stenosis group and the non-obvious stenosis group, and the differences were statistically significant (both P<0.05). The net flow and maximum flow in the center region of stenosis were lower than those in the proximal region of stenosis, and the differences were statistically significant (both P<0.05). The peak velocity in the center region and distal region of stenosis was higher than those in the proximal region of stenosis, and the difference was statistically significant (both P<0.05). There was a positive correlation between the net flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.270, 0.260, 0.320, respectively, P=0.044, 0.041, 0.036, respectively). There was a positive correlation between the maximum flow and eGFR at the TRAS patients proximal, center, and distal stenosis ( r=0.306, 0.276, 0.269, respectively, P=0.037, 0.041, 0.043, respectively). Conclusion:After TRAS, there is a significant change in blood flow status. The 4D Flow MRI can provide quantitative hemodynamic parameters to reflect the hemodynamic changes of TRAS.

Objective:To explore the correlation between renal function and abdominal aortic hemodynamic parameters based on four-dimensional flow(4D Flow) MRI in patients with chronic kidney disease (CKD).Methods:A cross-section prospective study was conducted on 73 patients diagnosed with CKD at First People′s Hospital of Changzhou between March 2021 and May 2023, as well as 13 volunteers without kidney injury. According to the estimated glomerular filtration rate (eGFR), the subjects were divided into CKD 1-3 stage group ( n=34), CKD 4-5 stage group ( n=39), and control group ( n=13). All subjects underwent 4D Flow MRI examination of the abdominal aorta, measuring pulse wave velocity (PWV), peak velocity, and maximum wall shear stress (WSS) at the proximal plane (Plane_1) and the higher renal artery opening plane (Plane_2) of the abdominal aorta. The differences in 4D Flow MRI hemodynamic parameters among the three groups were compared using a one-way analysis of variance or the Kruskal-Wallis test. The correlation between 4D Flow MRI hemodynamic parameters and eGFR was analyzed by using the Spearman correlation coefficient. The independent influencing factors that affect eGFR were analyzed by using multivariate linear regression analysis. Results:There were significant differences in abdominal aortic PWV and maximal WSS of Plane_1 and Plane_2 among the three groups ( H=10.38, P=0.006; F=11.16, P<0.001; F=4.75, P=0.011). There were no significant differences in the peak velocity of Plane_1 and Plane_2 among the three groups (both P>0.05). Abdominal aortic PWV was negatively correlated with eGFR ( r s=-0.30, P=0.005). There was a positive correlation between the maximal WSS of Plane_1 and Plane_2 with eGFR ( r s=0.39, P<0.001; r s=0.29, P=0.006). Abdominal aortic PWV and maximal WSS of Plane_1 were independent influencing factors of eGFR (b=-4.32, P=0.018; b=132.23, P=0.004). Conclusions:There is an independent correlation between renal function and abdominal aortic hemodynamic parameters based on 4D Flow MRI in patients with CKD, and abdominal aortic PWV and maximal WSS of Plane_1 were independent influencing factors of eGFR.

Objective:To explore the feasibility of chemical exchange saturation transfer (CEST) imaging at 3.0 T MRI in quantifying renal redox metabolism in vitro models and experimental animals.Methods:Redox metabolites in vitro models with physiological concentrations were prepared, including reduced metabolites (glutamate, alanine, glutathione) and oxidized metabolites (2-ketoglutarate, pyruvate, glutathione disulfide, ammonium hydroxide). CEST examinations were performed at 3.0 T MRI. The imaging parameters were as follows: CEST images with different saturation pulse intensity (B 1) (1, 2, 3, 4 μT) and a fixed radio frequency (RF) duration of 2 000 ms; CEST images with different RF durations (1 500 and 2 000 ms) were acquired with a fixed B 1 value of 2 μT to obtain the optimal scanning parameters. CEST examinations with optimized parameters were performed on the left kidneys of seven healthy rabbits, and the differences in magnetic resonance ratio asymmetry (MTR asym) between rabbit renal cortex and outer medulla were measured. A paired t-test was used to compare the differences. Results:The optimal B 1 for CEST examination of redox metabolites was 2 μT, and the optimal RF duration was 2 000 ms. The MTR asym peaks of glutathione disulfide, glutathione, glutamic acid, and alanine were at 3.75, 3.5, 3, and 1.5 ppm, respectively. The MTR asym peaks of pyruvate, 2-ketoglutarate, and ammonium hydroxide were at 1 ppm. The MTR asym peak values of reduced metabolites were higher than those of oxidized metabolites. When the B 1 value was 2 μT and the RF duration was 2 000 ms, the MTR asym signal of the renal cortex was (2.60±1.10) %, (2.86±1.32) %, (3.04±1.06) %, and (2.98±0.91) % at 1, 3, 3.5, and 3.75 ppm, respectively. The MTR asym signal of the outer medulla was (1.00±0.56) %, (2.43±0.94) %, (2.29±0.88) % and (1.98±0.58) %, respectively. The MTR asym signal of the renal cortex was higher than that of the outer medulla, and the differences were statistically significant ( t=3.04, P=0.023; t=2.56, P=0.043; t=3.50, P=0.013; t=3.45, P=0.014). Conclusion:CEST imaging at 3.0 T MRI can be used to quantitatively evaluate redox metabolism of healthy rabbit kidneys in vitro model and normal experimental rabbits.