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Kitada K, Kidoguchi S, Nakano D, Nishiyama A. Sodium/glucose cotransporter 2 and renoprotection: From the perspective of energy regulation and water conservation. J Pharmacol Sci 2021; 147:245-250. [PMID: 34507633 DOI: 10.1016/j.jphs.2021.07.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/19/2021] [Accepted: 07/26/2021] [Indexed: 01/14/2023] Open
Abstract
Sodium/glucose cotransporter 2 (SGLT2) is a renal low-affinity high-capacity sodium/glucose cotransporter expressed in the apical membrane of the early segment of proximal tubules. SGLT2 reabsorbs filtered glucose in the kidney, and its inhibitors represent a new class of oral medications used for type 2 diabetes mellitus, which act by increasing glucose and sodium excretion in urine, thereby reducing blood glucose levels. However, clinical trials showed marked improvement of renal outcomes, even in nondiabetic kidney diseases, although the underlying mechanism of this renoprotective effect is unclear. We showed that long-term excretion of salt by the kidneys, which predisposes to osmotic diuresis and water loss, induces a systemic body response for water conservation. The energy-intensive nature of water conservation leads to a reprioritization of systemic body energy metabolism. According to current data, use of SGLT2 inhibitors may result in similar reprioritization of energy metabolism to prevent dehydration. In this review article, we discuss the beneficial effects of SGLT2 inhibition from the perspective of energy metabolism and water conservation.
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Affiliation(s)
- Kento Kitada
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
| | - Satoshi Kidoguchi
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa, Japan; Division of Nephrology and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Daisuke Nakano
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Akira Nishiyama
- Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa, Japan
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2
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Circadian rhythm of the intrarenal renin-angiotensin system is caused by glomerular filtration of liver-derived angiotensinogen depending on glomerular capillary pressure in adriamycin nephropathy rats. Hypertens Res 2021; 44:618-627. [PMID: 33558668 DOI: 10.1038/s41440-021-00620-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/04/2020] [Accepted: 12/18/2020] [Indexed: 01/31/2023]
Abstract
Circadian fluctuation disorder of the intrarenal renin-angiotensin system (RAS) causes that of blood pressure (BP) and renal damage. In renal damage with an impaired glomerular filtration barrier, liver-derived angiotensinogen (AGT) filtered through damaged glomeruli regulates intrarenal RAS activity. Furthermore, glomerular permeability is more strongly affected by glomerular hypertension than by systemic hypertension. Thus, we aimed to clarify whether the circadian rhythm of intrarenal RAS activity is influenced by AGT filtered through damaged glomeruli due to glomerular capillary pressure. Rats with adriamycin nephropathy and an impaired glomerular filtration barrier were compared with control rats. In adriamycin nephropathy rats, olmesartan medoxomil (an angiotensin II type 1 receptor blocker) or hydralazine (a vasodilator) was administered, and the levels of intrarenal RAS components in the active and rest phases were evaluated. Moreover, the diameter ratio of afferent to efferent arterioles (A/E ratio), an indicator of glomerular capillary pressure, and the glomerular sieving coefficient (GSC) based on multiphoton microscopy in vivo imaging, which reflects glomerular permeability, were determined. Mild renal dysfunction was induced, and the systemic BP increased, resulting in increased A/E ratios in the adriamycin nephropathy rats compared with the control rats. Fluctuations in intrarenal RAS activity occurred in parallel with circadian fluctuations in glomerular capillary pressure, which disappeared with olmesartan treatment and were maintained with hydralazine treatment. Furthermore, the GSCs for AGT also showed similar changes. In conclusion, intrarenal RAS activity is influenced by the filtration of liver-derived AGT from damaged glomeruli due to circadian fluctuation disorder of the glomerular capillary pressure.
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Guan Y, Nakano D, Li L, Zheng H, Nishiyama A, Tian Y, Zhang L. Protease-Activated Receptor 1 Contributes to Microcirculation Failure and Tubular Damage in Renal Ischemia-Reperfusion Injury in Mice. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6665714. [PMID: 33681367 PMCID: PMC7925038 DOI: 10.1155/2021/6665714] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 01/25/2021] [Accepted: 02/08/2021] [Indexed: 12/11/2022]
Abstract
Ischemia-reperfusion- (IR-) induced kidney injury is difficult to avoid during renal transplantation and robot-assisted partial nephrectomy. Renal IR injury is characterized by tubular damage, microcirculation failure, and inflammation, which coordinately augment renal injury; however, no specific treatment is available for these conditions. Protease-activated receptor-1 (PAR-1) and its ligand, thrombin, are involved in coagulation and were shown to be associated with epithelial cell injury. Here, we hypothesized that PAR-1 exaggerated renal IR-induced tubular cell damage and microcirculation failure and that pharmacological inhibition of PAR-1 by Q94 could prevent these injuries. Renal warm IR increased the expression of PAR-1 in the renal tubules. Q94 attenuated renal IR-induced changes and histopathological damage. Microcirculation failure analyzed by congestion in the histopathology and blood cell flow examined by intravital multiphoton microscopy were suppressed by Q94 treatment. Q94 also dramatically increased tubular cell proliferation despite the lower renal damage. Thrombin suppressed cell proliferation and induced apoptosis in the tubules; these effects were prevented by Q94 treatment. Taken together, PAR-1 was associated with renal IR injury. Inhibition of PAR-1 ameliorated injury possibly by improving renal microcirculation and tubular cell survival/proliferation.
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Affiliation(s)
- Yu Guan
- Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Daisuke Nakano
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Lei Li
- Division of Kidney Transplantation, Department of Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Haofeng Zheng
- Division of Kidney Transplantation, Department of Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Akira Nishiyama
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Ye Tian
- Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Lei Zhang
- Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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Ranjit S, Lanzanò L, Libby AE, Gratton E, Levi M. Advances in fluorescence microscopy techniques to study kidney function. Nat Rev Nephrol 2020; 17:128-144. [PMID: 32948857 DOI: 10.1038/s41581-020-00337-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/30/2020] [Indexed: 02/07/2023]
Abstract
Fluorescence microscopy, in particular immunofluorescence microscopy, has been used extensively for the assessment of kidney function and pathology for both research and diagnostic purposes. The development of confocal microscopy in the 1950s enabled imaging of live cells and intravital imaging of the kidney; however, confocal microscopy is limited by its maximal spatial resolution and depth. More recent advances in fluorescence microscopy techniques have enabled increasingly detailed assessment of kidney structure and provided extraordinary insights into kidney function. For example, nanoscale precise imaging by rapid beam oscillation (nSPIRO) is a super-resolution microscopy technique that was originally developed for functional imaging of kidney microvilli and enables detection of dynamic physiological events in the kidney. A variety of techniques such as fluorescence recovery after photobleaching (FRAP), fluorescence correlation spectroscopy (FCS) and Förster resonance energy transfer (FRET) enable assessment of interaction between proteins. The emergence of other super-resolution techniques, including super-resolution stimulated emission depletion (STED), photoactivated localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM) and structured illumination microscopy (SIM), has enabled functional imaging of cellular and subcellular organelles at ≤50 nm resolution. The deep imaging via emission recovery (DIVER) detector allows deep, label-free and high-sensitivity imaging of second harmonics, enabling assessment of processes such as fibrosis, whereas fluorescence lifetime imaging microscopy (FLIM) enables assessment of metabolic processes.
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Affiliation(s)
- Suman Ranjit
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA. .,Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, CA, USA.
| | - Luca Lanzanò
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy.,Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy
| | - Andrew E Libby
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, CA, USA.
| | - Moshe Levi
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA.
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Abstract
Sepsis is a major cause of acute kidney injury (AKI) among patients in the intensive care unit. However, the numbers of basic science papers for septic AKI account for only 1% of all publications on AKI. This may be partially attributable to the specific pathophysiology of septic AKI as compared to that of the other types of AKI because it shows only modest histological changes despite functional decline and often requires real-time functional analysis. To increase the scope of research in this field, this article reviews the basic research information that has been reported thus far on the subject of septic AKI, mainly from the viewpoint of functional dysregulation, including some knowledge acquired with multiphoton intravital imaging. Moreover, the efficacy and limitation of the potential novel therapies are discussed. Finally, the author proposes several points that should be considered when designing the study, such as monitoring the long-term effects of the intervention and reflecting the clinical settings for identifying the molecular mechanisms and for challenging the intervention effects.
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Affiliation(s)
- Daisuke Nakano
- Department of Pharmacology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa, 761-0793, Japan.
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Lipopolysaccharide induces filtrate leakage from renal tubular lumina into the interstitial space via a proximal tubular Toll-like receptor 4-dependent pathway and limits sensitivity to fluid therapy in mice. Kidney Int 2019; 97:904-912. [PMID: 32107020 DOI: 10.1016/j.kint.2019.11.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 11/20/2019] [Accepted: 11/21/2019] [Indexed: 01/22/2023]
Abstract
Sustained oliguria during fluid resuscitation represents a perplexing problem in patients undergoing therapy for septic acute kidney injury. Here, we tested whether lipopolysaccharide induces filtrate leakage from the proximal tubular lumen into the interstitium, thus disturbing the recovery of urine output during therapy, such as fluid resuscitation, aiming to restore the glomerular filtration rate. Intravital imaging of the tubular flow rate in the proximal tubules in mice showed that lipopolysaccharide did not change the inflow rate of proximal tubule filtrate, reflecting an unchanged glomerular filtration rate, but significantly reduced the outflow rate, resulting in oliguria. Lipopolysaccharide disrupted tight junctions in proximal tubules and induced both paracellular leakage of filtered molecules and interstitial accumulation of extracellular fluid. These changes were diminished by conditional knockout of Toll-like receptor 4 in the proximal tubules. Importantly, these conditional knockout mice showed increased sensitivity to fluid resuscitation and attenuated acute kidney injury. Thus, lipopolysaccharide induced paracellular leakage of filtrate into the interstitium via a Toll-like receptor 4-dependent mechanism in the proximal tubules of endotoxemic mice. Hence, this leakage might diminish the efficacy of fluid resuscitation aiming to maintain renal hemodynamics and glomerular filtration rate.
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Guan Y, Nakano D, Zhang Y, Li L, Tian Y, Nishiyama A. A mouse model of renal fibrosis to overcome the technical variability in ischaemia/reperfusion injury among operators. Sci Rep 2019; 9:10435. [PMID: 31320707 PMCID: PMC6639321 DOI: 10.1038/s41598-019-46994-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 07/08/2019] [Indexed: 12/16/2022] Open
Abstract
The ischaemia-reperfusion (I/R) model is a widely used model of acute kidney injury (AKI) and renal fibrosis. However, the ischaemia duration that is long enough to cause broad fibrosis shows that a high mortality rate and a short ischaemia duration does not cause fibrosis, resulting in a large variation in fibrosis progression in this experimental model. Inter-operator variation occurs for I/R injury severity because the I/R procedure is complex, which results in poor reproducibility of subsequent fibrosis in the model. In the present study, we developed a renal fibrosis model in which the fibrosis progression for 8 weeks is predictable within 8 days. Three operators independently performed I/R followed by uninephrectomy at day 7 in mice. The aim was to create a model that would show a blood urea nitrogen (BUN) level >100 mg/dL at day 8 after I/R (day 1 after uninephrectomy). Although the ischaemia duration to satisfy this BUN criterion differed among operators, the mice developed anaemia, polyuria, and fibrosis in a similar manner under the same BUN criterion with a low mortality rate. Interstitial fibrosis had developed at week 8, which was strongly correlated with the BUN at day 8. This protocol allows operators to adjust the ischaemia duration based on the BUN criterion and to separate mice into the desired number of groups based on the BUN to study interventions against renal fibrosis.
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Affiliation(s)
- Yu Guan
- Department of Pharmacology, Kagawa University Medical School, Kagawa, Japan.,Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Daisuke Nakano
- Department of Pharmacology, Kagawa University Medical School, Kagawa, Japan.
| | - Yifan Zhang
- Department of Pharmacology, Kagawa University Medical School, Kagawa, Japan.,Department of No.2 Orthopedics, Shijiazhuang City No.1 Hospital, Shijiazhuang, Hebei, China
| | - Lei Li
- Department of Pharmacology, Kagawa University Medical School, Kagawa, Japan
| | - Ye Tian
- Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Akira Nishiyama
- Department of Pharmacology, Kagawa University Medical School, Kagawa, Japan
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Shroff UN, Schiessl IM, Gyarmati G, Riquier-Brison A, Peti-Peterdi J. Novel fluorescence techniques to quantitate renal cell biology. Methods Cell Biol 2019; 154:85-107. [PMID: 31493823 PMCID: PMC6748388 DOI: 10.1016/bs.mcb.2019.04.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Fluorescence microscopy techniques are powerful tools to study tissue dynamics, cellular function and biology both in vivo and in vitro. These tools allow for functional assessment and quantification along with qualitative analysis, thus providing a comprehensive understanding of various cellular processes under normal physiological and disease conditions. The main focus of this chapter is the recently developed method of serial intravital multiphoton microscopy that has helped shed light on the dynamic alterations of the spatial distribution and fate of single renal cells or cell populations and their migration patterns in the same tissue region over several days in response to various stimuli within the living kidney. This technique is very useful for studying in vivo the molecular and cellular mechanisms of tissue remodeling and repair after injury. In addition, complementary in vitro imaging tools are also described and discussed, like tissue clearing techniques and protein synthesis measurement in tissues in situ that provide an in depth assessment of changes at the cellular level. Thus, these novel fluorescence techniques can be effectively leveraged for different tissue types, experimental conditions as well as disease models to improve our understanding of renal cell biology.
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Affiliation(s)
- Urvi Nikhil Shroff
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Ina Maria Schiessl
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Georgina Gyarmati
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Anne Riquier-Brison
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Janos Peti-Peterdi
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States.
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Gyarmati G, Kadoya H, Moon JY, Burford JL, Ahmadi N, Gill IS, Hong YK, Dér B, Peti-Peterdi J. Advances in Renal Cell Imaging. Semin Nephrol 2019; 38:52-62. [PMID: 29291762 DOI: 10.1016/j.semnephrol.2017.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A great variety of cell imaging technologies are used routinely every day for the investigation of kidney cell types in applications ranging from basic science research to drug development and pharmacology, clinical nephrology, and pathology. Quantitative visualization of the identity, density, and fate of both resident and nonresident cells in the kidney, and imaging-based analysis of their altered function, (patho)biology, metabolism, and signaling in disease conditions, can help to better define pathomechanism-based disease subgroups, identify critical cells and structures that play a role in the pathogenesis, critically needed biomarkers of disease progression, and cell and molecular pathways as targets for novel therapies. Overall, renal cell imaging has great potential for improving the precision of diagnostic and treatment paradigms for individual acute kidney injury or chronic kidney disease patients or patient populations. This review highlights and provides examples for some of the recently developed renal cell optical imaging approaches, mainly intravital multiphoton fluorescence microscopy, and the new knowledge they provide for our better understanding of renal pathologies.
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Affiliation(s)
- Georgina Gyarmati
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Hiroyuki Kadoya
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA; Department of Nephrology and Hypertension, Kawasaki Medical School, Kurashiki, Japan
| | - Ju-Young Moon
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA; Division of Nephrology, Department of Internal Medicine, Kyung Hee University, College of Medicine, Seoul, Korea
| | - James L Burford
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Nariman Ahmadi
- Institute of Urology, Catherine & Joseph Aresty Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Inderbir S Gill
- Institute of Urology, Catherine & Joseph Aresty Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Young-Kwon Hong
- Department of Surgery and Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Bálint Dér
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - János Peti-Peterdi
- Department of Physiology and Neuroscience, Department of Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA.
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Zhang Y, Nakano D, Guan Y, Hitomi H, Uemura A, Masaki T, Kobara H, Sugaya T, Nishiyama A. A sodium-glucose cotransporter 2 inhibitor attenuates renal capillary injury and fibrosis by a vascular endothelial growth factor–dependent pathway after renal injury in mice. Kidney Int 2018; 94:524-535. [DOI: 10.1016/j.kint.2018.05.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 04/25/2018] [Accepted: 05/03/2018] [Indexed: 01/10/2023]
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11
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Liu J, Han Z, Chen G, Li Y, Zhang J, Xu J, van Zijl PCM, Zhang S, Liu G. CEST MRI of sepsis-induced acute kidney injury. NMR IN BIOMEDICINE 2018; 31:e3942. [PMID: 29897643 DOI: 10.1002/nbm.3942] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/15/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Sepsis-induced acute kidney injury (SAKI) is a major complication of kidney disease associated with increased mortality and faster progression. Therefore, the development of imaging biomarkers to detect septic AKI is of great clinical interest. In this study, we aimed to characterize the endogenous chemical exchange saturation transfer (CEST) MRI contrast in the lipopolysaccharide (LPS)-induced SAKI mouse model and to investigate the use of CEST MRI for detecting such injury. We used a SAKI mouse model that was generated by i.p. injection of 10 mg/kg LPS. The resulting kidney injury was confirmed by the elevation of serum creatinine and histology. MRI assessments were performed 24 h after LPS injection, including CEST MRI at different B1 strengths (1, 1.8 and 3 μT), T1 mapping, T2 mapping and conventional magnetization transfer contrast (MTC) MRI. The CEST MRI results were analyzed using Z-spectra, in which the normalized water signal saturation (Ssat /S0 ) is measured as a function of saturation frequency. Substantial decreases in CEST contrast were observed at both 3.5 and - 3.5 ppm frequency offset from water at all B1 powers, with the most significant difference obtained at a B1 of 1.8 μT. The average Ssat /S0 differences between injured and normal kidneys were 0.07 (0.55 ± 0.04 versus 0.62 ± 0.04, P = 0.0028) and 0.07 (0.50 ± 0.04 versus 0.57 ± 0.03, P = 0.0008) for 3.5 and - 3.5 ppm, respectively. In contrast, the T1 and T2 relaxation times and MTC contrast in the injured kidneys did not show a significant change compared with the normal control. Our results showed that CEST MRI is more sensitive to the pathological changes in injured kidneys than the changes in T1 , T2 and MTC effect, indicating its potential clinical utility for molecular imaging of renal diseases.
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Affiliation(s)
- Jing Liu
- Graduate College, Southern Medical University, Guangzhou, Guangdong, China
- Department of Radiology, Guangdong Provincial People's Hospital/Guangdong General Hospital, Guangzhou, Guangdong, China
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zheng Han
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Guoli Chen
- Department of Pathology and Laboratory Medicine, Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Yuguo Li
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jia Zhang
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jiadi Xu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Peter C M van Zijl
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Shuixing Zhang
- Graduate College, Southern Medical University, Guangzhou, Guangdong, China
- Department of Radiology, Guangdong Provincial People's Hospital/Guangdong General Hospital, Guangzhou, Guangdong, China
- Department of Radiology, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Guanshu Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
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12
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Guan Y, Nakano D, Zhang Y, Li L, Liu W, Nishida M, Kuwabara T, Morishita A, Hitomi H, Mori K, Mukoyama M, Masaki T, Hirano K, Nishiyama A. A protease-activated receptor-1 antagonist protects against podocyte injury in a mouse model of nephropathy. J Pharmacol Sci 2017; 135:S1347-8613(17)30128-7. [PMID: 29110957 DOI: 10.1016/j.jphs.2017.09.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/13/2017] [Accepted: 08/15/2017] [Indexed: 12/19/2022] Open
Abstract
The kidney expresses protease-activated receptor-1 (PAR-1). PAR-1 is known as a thrombin receptor, but its role in kidney injury is not well understood. In this study, we examined the contribution of PAR-1 to kidney glomerular injury and the effects of its inhibition on development of nephropathy. Mice were divided into 3 groups: control, doxorubicin + vehicle (15 mg/kg doxorubicin and saline) and doxorubicin + Q94 (doxorubicin at 15 mg/kg and the PAR-1 antagonist Q94 at 5 mg/kg/d) groups. Where indicated, doxorubicin was administered intravenously and PAR-1 antagonist or saline vehicle by subcutaneous osmotic mini-pump. PAR-1 expression was increased in glomeruli of mice treated with doxorubicin. Q94 treatment significantly suppressed the increased albuminuria in these nephropathic mice. Pathological analysis showed that Q94 treatment significantly attenuated periodic acid-Schiff and desmin staining, indicators of podocyte injury, and also decreased glomerular levels of podocin and nephrin. Furthermore, thrombin increased intracellular calcium levels in podocytes. This increase was suppressed by Q94 and Rox4560, a transient receptor potential cation channel (TRPC)3/6 antagonist. In addition, both Q94 and Rox4560 suppressed the doxorubicin-induced increase in activities of caspase-9 and caspase-3 in podocytes. These data suggested that PAR-1 contributes to development of podocyte and glomerular injury and that PAR-1 antagonists have therapeutic potential.
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Affiliation(s)
- Yu Guan
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Daisuke Nakano
- Department of Pharmacology, Kagawa University, Kagawa, Japan.
| | - Yifan Zhang
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Lei Li
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Wenhua Liu
- Department of Cardiovascular Physiology, Kagawa University, Kagawa, Japan
| | - Motohiro Nishida
- Division of Cardiocirculatory Signaling, Okazaki Institute for Integrative Bioscience (National Institute for Physiological Sciences), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Takashige Kuwabara
- Department of Nephrology, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
| | - Asahiro Morishita
- Department of Gastroenterology & Neurology, Kagawa University, Kagawa, Japan
| | - Hirofumi Hitomi
- Department of Pharmacology, Kagawa University, Kagawa, Japan
| | - Kiyoshi Mori
- Department of Nephrology and Kidney Research, Shizuoka General Hospital, Shizuoka, Japan
| | - Masashi Mukoyama
- Department of Nephrology, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
| | - Tsutomu Masaki
- Department of Gastroenterology & Neurology, Kagawa University, Kagawa, Japan
| | - Katsuya Hirano
- Department of Cardiovascular Physiology, Kagawa University, Kagawa, Japan
| | - Akira Nishiyama
- Department of Pharmacology, Kagawa University, Kagawa, Japan
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