炎症反应通过上调CD36表达促进小鼠肾脏损伤
|
摘要
目的:探讨慢性炎症对小鼠肾脏CD36表达的影响及其在小鼠肾脏损伤中的作用。方法:将8周龄雄性C57BL/6J小鼠和CD36基因敲除(CD36KO)小鼠随机分为C57BL/6J生理盐水注射组、C57BL/6J酪蛋白注射组和CD36KO酪蛋白注射组,每组8只。高脂喂养处理14周后,收集小鼠血清、24 h尿液和肾组织样本。ELISA试剂盒检测血清中肿瘤坏死因子α(TNF-α)含量,全自动生化仪测定血、尿肾功能指标,HE染色和Masson染色分析肾脏病理改变,real-time PCR和Western blot检测肾脏组织中CD36及炎症/趋化因子(MCP-1、IL-6和TNF-α)m RNA和蛋白的表达,试剂盒测定组织内过氧化氢含量,免疫组化染色测定肾组织Nrf2和TGF-β1的蛋白表达。结果:与生理盐水注射组相比,酪蛋白注射能增强C57BL/6J小鼠血清TNF-α含量和肾组织中TNF-α的蛋白表达(P <0. 05),提示酪蛋白注射能成功诱导小鼠全身和肾脏局部的慢性炎症。同时酪蛋白注射显著促进了小鼠肾组织的CD36和TGF-β1蛋白表达,引起肾小球硬化、蛋白尿和血清肌酐含量显著增加,组织过氧化氢含量明显增加,Nrf2含量和抗氧化能力明显降低(P <0. 05)。而酪蛋白处理的CD36基因敲除小鼠肾组织病理学改变不明显,血、尿肾功能指标和尿量较酪蛋白处理的C57BL/6J小鼠明显降低,且肾组织过氧化氢含量低于酪蛋白处理的C57BL/6J小鼠(P <0. 05)。结论:炎症应激通过促进小鼠肾组织CD36表达,促进氧化应激,导致小鼠肾损伤。
AIM: To investigate the role of CD36 in casein-induced mouse renal injury. METHODS: Eightweek-old male C57BL/6J mice and CD36 knockout( CD36KO) mice were randomly divided into C57BL/6J saline injection group,C57BL/6J casein injection group and CD36 KO casein injection group( n = 8 in each group). After 14 weeks of treatment with high-fat diet,the mouse serum,24 h urine and kidney tissue samples were collected for analysis. The serum content of tumor necrosis factor-α( TNF-α) was measured by ELISA. The renal function markers in the serum and urine were determined by an automatic biochemical analyzer. The pathological changes of the kidney were observed by HE staining and Masson staining. The expression of CD36 and cytokines/chemokines( TNF-α,IL-6 and MCP-1) at m RNA and protein levels in the renal tissues were determined by real-time PCR and Western blot. The content of tissue hydrogen peroxide( H_2O_2) was measured by a commercial kit. The protein levels of Nrf2 and TGF-β1 in the renal tissues were measured by immunohistochemical staining. RESULTS: Compared with saline injection group,casein injection increased the level of TNF-α in the serum and in the kidney tissues of C57BL/6J mice( P < 0. 05),suggesting that casein injection successfully induced chronic inflammation in C57BL/6J mice. Casein injection also promoted the protein expression of CD36 and TGF-β1 in the renal tissues of the C57BL/6J mice,accompanied with glomerular sclerosis,proteinuria,increased serum creatinine content,increased H_2O_2 content,and decreased Nrf2 protein level and the ability of antioxidant in the kidneys( P < 0. 05). Furthermore,CD36 deficiency protected the mice from casein-induced renal injury,as evidenced by improved kidney pathological changes and decreased proteinuria. The content of H_2O_2 in the kidneys of casein-treated CD36 knockout mice was also lower than that in casein-treated C57BL/6J mice. CONCLUSION: Inflammatory responses promote the oxidative stress and renal injury in a CD36-dependent manner.
AIM: To investigate the role of CD36 in casein-induced mouse renal injury. METHODS: Eightweek-old male C57BL/6J mice and CD36 knockout( CD36KO) mice were randomly divided into C57BL/6J saline injection group,C57BL/6J casein injection group and CD36 KO casein injection group( n = 8 in each group). After 14 weeks of treatment with high-fat diet,the mouse serum,24 h urine and kidney tissue samples were collected for analysis. The serum content of tumor necrosis factor-α( TNF-α) was measured by ELISA. The renal function markers in the serum and urine were determined by an automatic biochemical analyzer. The pathological changes of the kidney were observed by HE staining and Masson staining. The expression of CD36 and cytokines/chemokines( TNF-α,IL-6 and MCP-1) at m RNA and protein levels in the renal tissues were determined by real-time PCR and Western blot. The content of tissue hydrogen peroxide( H_2O_2) was measured by a commercial kit. The protein levels of Nrf2 and TGF-β1 in the renal tissues were measured by immunohistochemical staining. RESULTS: Compared with saline injection group,casein injection increased the level of TNF-α in the serum and in the kidney tissues of C57BL/6J mice( P < 0. 05),suggesting that casein injection successfully induced chronic inflammation in C57BL/6J mice. Casein injection also promoted the protein expression of CD36 and TGF-β1 in the renal tissues of the C57BL/6J mice,accompanied with glomerular sclerosis,proteinuria,increased serum creatinine content,increased H_2O_2 content,and decreased Nrf2 protein level and the ability of antioxidant in the kidneys( P < 0. 05). Furthermore,CD36 deficiency protected the mice from casein-induced renal injury,as evidenced by improved kidney pathological changes and decreased proteinuria. The content of H_2O_2 in the kidneys of casein-treated CD36 knockout mice was also lower than that in casein-treated C57BL/6J mice. CONCLUSION: Inflammatory responses promote the oxidative stress and renal injury in a CD36-dependent manner.
引文
[1]Zhong S,Zhao L,Li Q,et al.Inflammatory stress exacerbated mesangial foam cell formation and renal injury via disrupting cellular cholesterol homeostasis[J].Inflammation,2015,38(3):959-971.
[2]Ioannou K,Stel VS,Dounousi E,et al.Inflammation,endothelial dysfunction and increased left ventricular mass in chronic kidney disease(CKD)patients:a longitudinal study[J].PLo S One,2015,10(9):e0138461.
[3]Javard R,Grimes C,Bau-Gaudreault L,et al.Acutephase proteins and iron status in cats with chronic kidney disease[J].J Vet Intern Med,2017,31(2):457-464.
[4]Sasaki K,Ma Z,Khatlani TS,et al.Evaluation of feline serum amyloid A(SAA)as an inflammatory marker[J].JVet Med Sci,2003,65(4):545-548.
[5]Chen Y,Kennedy DJ,Ramakrishnan DP,et al.Oxidized LDL-bound CD36 recruits an Na+/K+-ATPase-Lyn complex in macrophages that promotes atherosclerosis[J].Sci Signal,2015,8(393):ra91.
[6]Doens D,Valiente PA,Mfuh AM,et al.Identification of inhibitors of CD36-amyloid beta binding as potential agents for Alzheimer’s disease[J].ACS Chem Neurosci,2017,8(6):1232-1241.
[7]Susztak K,Ciccone E,Mccue P,et al.Multiple metabolic hits converge on CD36 as novel mediator of tubular epithelial apoptosis in diabetic nephropathy[J].PLo S Med,2005,2(2):e45.
[8]Yang YL,Lin SH,Chuang LY,et al.CD36 is a novel and potential anti-fibrogenic target in albumin-induced renal proximal tubule fibrosis[J].J Cell Biochem,2007,101(3):735-744.
[9]Liang S,Wang WL,Zhu FL,et al.Chinese observational prospective study of ageing population with chronic kidney disease(C-OPTION):a study protocol[J].BMJ Open,2018,8(2):e019457.
[10]Li PK,Ma TK.Global impact of nephropathies[J].Nephrology(Carlton),2017,22(Suppl 4):9-13.
[11]Zimmermann J,Herrlinger S,Pruy A,et al.Inflammation enhances cardiovascular risk and mortality in hemodialysis patients[J].Kidney Int,1999,55(2):648-658.
[12]Oliveira EA,Mak RH.Progression of chronic kidney disease in children:role of glomerular hemodynamics and interstitial fibrosis[J].Curr Opin Pediatr,2018,30(2):220-227.
[13]Ma KL,Ruan XZ,Powis SH,et al.Inflammatory stress exacerbates lipid accumulation in hepatic cells and fatty livers of apolipoprotein E knockout mice[J].Hepatology,2008,48(3):770-781.
[14]Osman B,Doller A,Akool El-S,et al.Rapamycin induces the TGFβ1/Smad signaling cascade in renal mesangial cells upstream of m TOR[J].Cell Signal,2009,21(12):1806-1817.
[2]Ioannou K,Stel VS,Dounousi E,et al.Inflammation,endothelial dysfunction and increased left ventricular mass in chronic kidney disease(CKD)patients:a longitudinal study[J].PLo S One,2015,10(9):e0138461.
[3]Javard R,Grimes C,Bau-Gaudreault L,et al.Acutephase proteins and iron status in cats with chronic kidney disease[J].J Vet Intern Med,2017,31(2):457-464.
[4]Sasaki K,Ma Z,Khatlani TS,et al.Evaluation of feline serum amyloid A(SAA)as an inflammatory marker[J].JVet Med Sci,2003,65(4):545-548.
[5]Chen Y,Kennedy DJ,Ramakrishnan DP,et al.Oxidized LDL-bound CD36 recruits an Na+/K+-ATPase-Lyn complex in macrophages that promotes atherosclerosis[J].Sci Signal,2015,8(393):ra91.
[6]Doens D,Valiente PA,Mfuh AM,et al.Identification of inhibitors of CD36-amyloid beta binding as potential agents for Alzheimer’s disease[J].ACS Chem Neurosci,2017,8(6):1232-1241.
[7]Susztak K,Ciccone E,Mccue P,et al.Multiple metabolic hits converge on CD36 as novel mediator of tubular epithelial apoptosis in diabetic nephropathy[J].PLo S Med,2005,2(2):e45.
[8]Yang YL,Lin SH,Chuang LY,et al.CD36 is a novel and potential anti-fibrogenic target in albumin-induced renal proximal tubule fibrosis[J].J Cell Biochem,2007,101(3):735-744.
[9]Liang S,Wang WL,Zhu FL,et al.Chinese observational prospective study of ageing population with chronic kidney disease(C-OPTION):a study protocol[J].BMJ Open,2018,8(2):e019457.
[10]Li PK,Ma TK.Global impact of nephropathies[J].Nephrology(Carlton),2017,22(Suppl 4):9-13.
[11]Zimmermann J,Herrlinger S,Pruy A,et al.Inflammation enhances cardiovascular risk and mortality in hemodialysis patients[J].Kidney Int,1999,55(2):648-658.
[12]Oliveira EA,Mak RH.Progression of chronic kidney disease in children:role of glomerular hemodynamics and interstitial fibrosis[J].Curr Opin Pediatr,2018,30(2):220-227.
[13]Ma KL,Ruan XZ,Powis SH,et al.Inflammatory stress exacerbates lipid accumulation in hepatic cells and fatty livers of apolipoprotein E knockout mice[J].Hepatology,2008,48(3):770-781.
[14]Osman B,Doller A,Akool El-S,et al.Rapamycin induces the TGFβ1/Smad signaling cascade in renal mesangial cells upstream of m TOR[J].Cell Signal,2009,21(12):1806-1817.