Young Chul Kim, Hadi Fattah, Yiling Fu, Josselin Nespoux, Volker Vallon
{"title":"瘦素受体在肾小管中的表达是稀疏的,但与瘦素依赖性肾基因的表达和功能有关。","authors":"Young Chul Kim, Hadi Fattah, Yiling Fu, Josselin Nespoux, Volker Vallon","doi":"10.1152/ajprenal.00279.2022","DOIUrl":null,"url":null,"abstract":"<p><p>Leptin regulates energy balance via leptin receptors expressed in central and peripheral tissues, but little is known about leptin-sensitive kidney genes and the role of the tubular leptin receptor (Lepr) in response to a high-fat diet (HFD). Quantitative RT-PCR analysis of Lepr splice variants A, B, and C revealed a ratio of ∼100:10:1 in the mouse kidney cortex and medulla, with medullary levels being ∼10 times higher. Leptin replacement in <i>ob</i>/<i>ob</i> mice for 6 days reduced hyperphagia, hyperglycemia, and albuminuria, associated with normalization of kidney mRNA expression of molecular markers of glycolysis, gluconeogenesis, amino acid synthesis, and megalin. Normalization of leptin for 7 h in <i>ob</i>/<i>ob</i> mice did not normalize hyperglycemia or albuminuria. Tubular knockdown of Lepr [Pax8-Lepr knockout (KO)] and in situ hybridization revealed a minor fraction of Lepr mRNA in tubular cells compared with endothelial cells. Nevertheless, Pax8-Lepr KO mice had lower kidney weight. Moreover, while HFD-induced hyperleptinemia, increases in kidney weight and glomerular filtration rate, and a modest blood pressure lowering effect were similar compared with controls, they showed a blunted rise in albuminuria. Use of Pax8-Lepr KO and leptin replacement in <i>ob</i>/<i>ob</i> mice identified acetoacetyl-CoA synthetase and gremlin 1 as tubular Lepr-sensitive genes that are increased and reduced by leptin, respectively. In conclusion, leptin deficiency may increase albuminuria via systemic metabolic effects that impinge on kidney megalin expression, whereas hyperleptinemia may induce albuminuria by direct tubular Lepr effects. Implications of Lepr variants and the novel tubular Lepr/acetoacetyl-CoA synthetase/gremlin 1 axis remain to be determined.<b>NEW & NOTEWORTHY</b> This study provides new insights into kidney gene expression of leptin receptor splice variants, leptin-sensitive kidney gene expression, and the role of the leptin receptor in renal tubular cells for the response to diet-induced hyperleptinemia and obesity including albuminuria.</p>","PeriodicalId":7588,"journal":{"name":"American Journal of Physiology-renal Physiology","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10228677/pdf/","citationCount":"0","resultStr":"{\"title\":\"Expression of leptin receptor in renal tubules is sparse but implicated in leptin-dependent kidney gene expression and function.\",\"authors\":\"Young Chul Kim, Hadi Fattah, Yiling Fu, Josselin Nespoux, Volker Vallon\",\"doi\":\"10.1152/ajprenal.00279.2022\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Leptin regulates energy balance via leptin receptors expressed in central and peripheral tissues, but little is known about leptin-sensitive kidney genes and the role of the tubular leptin receptor (Lepr) in response to a high-fat diet (HFD). Quantitative RT-PCR analysis of Lepr splice variants A, B, and C revealed a ratio of ∼100:10:1 in the mouse kidney cortex and medulla, with medullary levels being ∼10 times higher. Leptin replacement in <i>ob</i>/<i>ob</i> mice for 6 days reduced hyperphagia, hyperglycemia, and albuminuria, associated with normalization of kidney mRNA expression of molecular markers of glycolysis, gluconeogenesis, amino acid synthesis, and megalin. Normalization of leptin for 7 h in <i>ob</i>/<i>ob</i> mice did not normalize hyperglycemia or albuminuria. Tubular knockdown of Lepr [Pax8-Lepr knockout (KO)] and in situ hybridization revealed a minor fraction of Lepr mRNA in tubular cells compared with endothelial cells. Nevertheless, Pax8-Lepr KO mice had lower kidney weight. Moreover, while HFD-induced hyperleptinemia, increases in kidney weight and glomerular filtration rate, and a modest blood pressure lowering effect were similar compared with controls, they showed a blunted rise in albuminuria. Use of Pax8-Lepr KO and leptin replacement in <i>ob</i>/<i>ob</i> mice identified acetoacetyl-CoA synthetase and gremlin 1 as tubular Lepr-sensitive genes that are increased and reduced by leptin, respectively. In conclusion, leptin deficiency may increase albuminuria via systemic metabolic effects that impinge on kidney megalin expression, whereas hyperleptinemia may induce albuminuria by direct tubular Lepr effects. Implications of Lepr variants and the novel tubular Lepr/acetoacetyl-CoA synthetase/gremlin 1 axis remain to be determined.<b>NEW & NOTEWORTHY</b> This study provides new insights into kidney gene expression of leptin receptor splice variants, leptin-sensitive kidney gene expression, and the role of the leptin receptor in renal tubular cells for the response to diet-induced hyperleptinemia and obesity including albuminuria.</p>\",\"PeriodicalId\":7588,\"journal\":{\"name\":\"American Journal of Physiology-renal Physiology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.7000,\"publicationDate\":\"2023-06-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10228677/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"American Journal of Physiology-renal Physiology\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1152/ajprenal.00279.2022\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2023/4/27 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q1\",\"JCRName\":\"PHYSIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"American Journal of Physiology-renal Physiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1152/ajprenal.00279.2022","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/4/27 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"PHYSIOLOGY","Score":null,"Total":0}
Expression of leptin receptor in renal tubules is sparse but implicated in leptin-dependent kidney gene expression and function.
Leptin regulates energy balance via leptin receptors expressed in central and peripheral tissues, but little is known about leptin-sensitive kidney genes and the role of the tubular leptin receptor (Lepr) in response to a high-fat diet (HFD). Quantitative RT-PCR analysis of Lepr splice variants A, B, and C revealed a ratio of ∼100:10:1 in the mouse kidney cortex and medulla, with medullary levels being ∼10 times higher. Leptin replacement in ob/ob mice for 6 days reduced hyperphagia, hyperglycemia, and albuminuria, associated with normalization of kidney mRNA expression of molecular markers of glycolysis, gluconeogenesis, amino acid synthesis, and megalin. Normalization of leptin for 7 h in ob/ob mice did not normalize hyperglycemia or albuminuria. Tubular knockdown of Lepr [Pax8-Lepr knockout (KO)] and in situ hybridization revealed a minor fraction of Lepr mRNA in tubular cells compared with endothelial cells. Nevertheless, Pax8-Lepr KO mice had lower kidney weight. Moreover, while HFD-induced hyperleptinemia, increases in kidney weight and glomerular filtration rate, and a modest blood pressure lowering effect were similar compared with controls, they showed a blunted rise in albuminuria. Use of Pax8-Lepr KO and leptin replacement in ob/ob mice identified acetoacetyl-CoA synthetase and gremlin 1 as tubular Lepr-sensitive genes that are increased and reduced by leptin, respectively. In conclusion, leptin deficiency may increase albuminuria via systemic metabolic effects that impinge on kidney megalin expression, whereas hyperleptinemia may induce albuminuria by direct tubular Lepr effects. Implications of Lepr variants and the novel tubular Lepr/acetoacetyl-CoA synthetase/gremlin 1 axis remain to be determined.NEW & NOTEWORTHY This study provides new insights into kidney gene expression of leptin receptor splice variants, leptin-sensitive kidney gene expression, and the role of the leptin receptor in renal tubular cells for the response to diet-induced hyperleptinemia and obesity including albuminuria.
期刊介绍:
The American Journal of Physiology - Renal Physiology publishes original manuscripts on timely topics in both basic science and clinical research. Published articles address a broad range of subjects relating to the kidney and urinary tract, and may involve human or animal models, individual cell types, and isolated membrane systems. Also covered are the pathophysiological basis of renal disease processes, regulation of body fluids, and clinical research that provides mechanistic insights. Studies of renal function may be conducted using a wide range of approaches, such as biochemistry, immunology, genetics, mathematical modeling, molecular biology, as well as physiological and clinical methodologies.