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1.
Transplant Direct ; 10(5): e1620, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38617463

RESUMO

Background: Pancreas transplant volumes are limited because of poor utilization of "extended criteria grafts." Prolonged cold ischemia is a risk factor associated with poor allograft survival. We aimed to establish the feasibility of transplantation using grafts subjected to prolonged cold ischemia and determine whether these grafts could be optimized using normothermic ex vivo perfusion (NEVP) in a porcine model. Methods: The study population consisted of 35 to 40 kg male Yorkshire pigs in an allotransplantation model with a 3-d survival plan for recipients. Control grafts were subjected to cold storage (CS) in a University of Wisconsin solution for 21 to 24 h (n = 6), whereas the test group received an additional 3 h NEVP after CS of 21 h (n = 5). Results: The 3-d survival was 60% in the NEVP arm versus 0% in the control arm (P = 0.008; log rank). Graft parenchyma was 60% to 70% preserved in the NEVP arm at necropsy on gross appearance. In addition, the islet function was well preserved, and both the pancreas (including the islets) and the duodenal morphology were maintained histologically. The intravenous glucose tolerance test on the day of euthanasia was in the normoglycemic range for 80% of cases in the NEVP arm. Conclusions: Optimization of pancreas grafts exposed to extended CS with NEVP seems promising at rescuing and reanimating these grafts for transplantation, resulting in significantly improved survival in a porcine pancreas transplant model.

2.
Transplantation ; 108(1): 184-191, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505906

RESUMO

BACKGROUND: Ex vivo machine perfusion is a novel preservation technique for storing and assessing marginal kidney grafts. All ex vivo perfusion techniques have advantages and shortcomings. The current study analyzed whether a combination of oxygenated hypothermic machine perfusion (oxHMP) followed by a short period of normothermic ex vivo kidney perfusion (NEVKP) could combine the advantages of both techniques. METHODS: Porcine kidneys were exposed to 30 min of warm ischemia followed by perfusion. Kidneys underwent either 16-h NEVKP or 16-h oxHMP. The third group was exposed to 16-h oxHMP followed by 3-h NEVKP (oxHMP + NEVKP group). After contralateral nephrectomy, grafts were autotransplanted and animals were followed up for 8 d. RESULTS: All animals survived the follow-up period. Grafts preserved by continuous NEVKP showed improved function with lower peak serum creatinine and more rapid recovery compared with the other 2 groups. Urine neutrophil gelatinase-associated lipocalin, a marker of kidney injury, was found to be significantly lowered on postoperative day 3 in the oxHMP + NEVKP group compared with the other 2 groups. CONCLUSIONS: A short period of NEVKP after oxHMP provides comparable short-term outcomes to prolonged NEVKP and is superior to oxHMP alone. A combination of oxHMP with end-ischemic NEVKP could be an attractive, practical strategy to combine the advantages of both preservation techniques.


Assuntos
Transplante de Rim , Suínos , Animais , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , Preservação de Órgãos/métodos , Modelos Animais , Rim/cirurgia , Perfusão/efeitos adversos , Perfusão/métodos
3.
Kidney Int Rep ; 8(6): 1192-1200, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37284685

RESUMO

Introduction: An ideal endogenous molecule for measuring glomerular filtration rate (GFR) is still unknown. However, a rare enantiomer of serine, d-serine, is useful in GFR measurement. This study explored the potential of other d-amino acids for kidney function assessment. Methods: This was a cross-sectional observational study of 207 living kidney transplant donors and recipients, for whom GFR was measured using clearance of inulin (C-in). Associations between levels of d-amino acids and GFR were analyzed using multivariate factor analysis. Fractional excretion (FE), a ratio of the clearance of a substance to C-in as a standard molecule, was calculated to monitor the excretion ratio after glomerular filtration. Dissociation from an ideal FE of 100% was assessed as a bias. Proportional bias against C-in was calculated using Deming regression. Results: Multivariate analysis identified the blood level of d-asparagine to reflect GFR. Means of blood d-asparagine and clearance of d-asparagine (C-d-Asn) were 0.21 µM and 65.0 ml/min per 1.73 m2, respectively. Inulin-based FE (FEin) of d-asparagine was 98.67% (95% confidence interval [CI]: 96.43-100.90%) and less biased than those of known GFR markers, such as FEin of creatinine (147.93 [145.39-150.46]; P < 0.001) and d-serine (84.84 [83.22-86.46]; P < 0.001). A proportional bias of C-d-Asn to C-in was -7.8% (95% CI, -14.5 to -0.6%), which was minor compared to those of clearance of creatinine (-34.5% [-37.9 to -31.0%]) and d-serine (21.2% [13.9-28.9]). Conclusion: D-Asparagine acts similar to inulin in the kidney. Therefore, d-asparagine is an ideal endogenous molecule that can be used for GFR measurement.

4.
Transpl Int ; 36: 10936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252614

RESUMO

Pancreas transplantation is the only curative treatment for patients with complicated diabetes, and organ shortage is a common and increasing problem. Strategies to expand the donor pool are needed, and normothermic ex vivo perfusion of the pancreas has the potential to test and repair grafts before implantation. Between January 2021 and April 2022, six human pancreases, declined for transplantation or islet isolation, were perfused using a previously established method by our group. All 6 cases were successfully perfused for 4 h, with minimal edema. The mean age of the donors was 44.16 ± 13.8 years. Five grafts were obtained from neurological death donors, and one was obtained from a donation after cardiac death. The mean glucose and lactate levels decreased throughout perfusion and insulin levels increased. All 6 grafts were metabolically active during perfusion and histopathology showed minimal tissue injury and no edema. Human normothermic ex vivo perfusion of the pancreas is feasible and safe and has the potential to expand the donor pool. Future studies will focus on tests and biomarkers for the assessment of grafts.


Assuntos
Preservação de Órgãos , Doadores de Tecidos , Humanos , Adulto , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Estudos de Viabilidade , Perfusão/métodos , Pâncreas , Aloenxertos
5.
J Vis Exp ; (192)2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36807320

RESUMO

Translational surgical research models in swine are crucial for developing safe preclinical protocols. However, the success of the experimental surgeries does not solely rely on the research team's surgical skills; perioperative care and management procedures, like intubation, central venous line, and arterial line placement, are necessary and of the utmost importance for favorable experiment results. As it is uncommon for research teams to have anesthesiologists or any other staff other than the surgical team, the surgical team involved in translational research must acquire and/or develop the skills to perform the perioperative care. The purpose of this paper is to show the techniques of intubation, central venous catheter, and arterial line placement used and perfected at the Toronto Organ Preservation Laboratory over the last 10 years, to be used as a reference for future researchers joining either this team or any other lab performing translational research protocols in swine and/or abdominal transplantation.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Suínos , Animais , Pesquisa Translacional Biomédica , Cateterismo , Artérias , Intubação Intratraqueal , Cateterismo Venoso Central/métodos
6.
J Vis Exp ; (185)2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35938839

RESUMO

Despite the promising results of pancreas transplantation in type 1 diabetes mellitus and metabolic syndrome, the biggest concern around this state-of-the-art technique remains the paucity of organs deemed fit for transplantation. High intravascular resistance, delicate intraparenchymal capillary framework, and complex lobular anatomy around the mesenteric vasculature are what make this organ more susceptible to injury and less tolerant to trivial trauma compared to organs such as the liver and kidney. Meticulous surgical dissection and judicious tissue handling form the cornerstone of the entire exercise of pancreas transplantation. Owing to morphological similarity between the anatomy of the porcine pancreas to the surrounding mesenteric vessels and the organs when compared to the human anatomy, demonstration of the technique in the porcine model could help to most accurately extrapolate this to a human setting. The present article aims to outline the essential surgical tips and tricks that need to be followed, in order to ensure a higher success rate of transplantation of this highly susceptible organ in a porcine 3-day survival model.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante de Pâncreas , Animais , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Rim , Fígado , Pâncreas/cirurgia , Transplante de Pâncreas/métodos , Suínos , Transplante Homólogo
7.
J Vis Exp ; (185)2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35969078

RESUMO

Pancreas transplantation (PTx) is a curative treatment for people who live with the burden of a diagnosis of diabetes mellitus (DM). However, due to organ shortages and increasing numbers of patients being listed for PTx, new strategies are needed to increase the number of available grafts for transplantation. Static cold storage (SCS) is considered the gold standard for standard criteria organs. However, standard criteria donors (SCD) are becoming scarce and new strategies that can increase the rate of organ acceptance from extended criteria donors (ECD) are urgently needed. Normothermic ex vivo perfusion (NEVP) is one of the strategies that has become increasingly popular over the past couple of decades. This preservation method has already been used successfully in other organs (liver, kidneys, and lungs) but has been minimally explored in pancreas transplantation. The few papers that describe the method for pancreas show little success, edema being one of the major issues. The following manuscript describes the successful NEVP method and setup developed by our group to perfuse swine pancreas.


Assuntos
Preservação de Órgãos , Doadores de Tecidos , Aloenxertos , Humanos , Preservação de Órgãos/métodos , Pâncreas/cirurgia , Perfusão/métodos
8.
Biomater Sci ; 10(11): 2972-2990, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35521809

RESUMO

When decellularizing kidneys, it is important to maintain the integrity of the acellular extracellular matrix (ECM), including associated adhesion proteins and growth factors that allow recellularized cells to adhere and migrate according to ECM specificity. Kidney decellularization requires the ionic detergent sodium dodecyl sulfate (SDS); however, this results in a loss of ECM proteins important for cell adherence, migration, and growth, particularly glycosaminoglycan (GAG)-associated proteins. Here, we demonstrate that using submicellar concentrations of SDS results in a greater retention of structural proteins, GAGs, growth factors, and cytokines. When porcine kidney ECM scaffolds were recellularized using human adult primary renal epithelial cells (RECs), the ECM promoted cell survival and the uniform distribution of cells throughout the ECM. Cells maintained the expression of mature renal epithelial markers but did not organize on the ECM, indicating that mature cells are unable to migrate to specific locations on ECM scaffolds.


Assuntos
Proteínas da Matriz Extracelular , Alicerces Teciduais , Animais , Células Epiteliais , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Humanos , Rim/química , Suínos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
9.
Am J Transplant ; 22(5): 1339-1349, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35258859

RESUMO

Pancreas transplantation improves and extends the life of patients with insulin-dependent diabetes. Pancreata from extended criteria donors have been increasingly used due to the scarcity of available grafts. Normothermic ex situ pancreas perfusion (NESPP) can keep grafts metabolically active, potentially allowing for assessment and organ repair, and could improve outcomes of marginal grafts. A novel NESPP technique was developed and tested. Porcine pancreata were removed after a short period of warm ischemia and subjected to 6 h of NESPP. Perfusion parameters, potential graft assessment markers and graft injury were measured. Next, pancreata subjected to 3 h of NESPP were transplanted and animals were followed for up to 3 days. Graft function and injury post-transplantation were evaluated. Using this novel system of perfusion, pancreata were perfused for an extended period of time with minimal edema. Histology at the end of perfusion showed intact islet cells with only mild signs of tissue injury. NESPP transplanted grafts showed immediate function after transplantation, with glucose levels in normal range. NESPP maintains a physiologic environment and excellent graft function without causing significant graft injury. Porcine pancreas transplantation is feasible and allows for in vivo graft assessment of pancreas function and injury after NESPP.


Assuntos
Transplante de Pâncreas , Animais , Humanos , Preservação de Órgãos/métodos , Pâncreas/cirurgia , Perfusão/métodos , Suínos , Isquemia Quente
10.
Int J Urol ; 29(3): 206-211, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34897833

RESUMO

OBJECTIVES: Post-transplant lymphoproliferative disorder is a potentially life-threatening complication that has a greater risk of occurrence in the setting of immunosuppression and oncogenic viral infections after transplant surgery. Few studies have reported the cumulative incidence, histological subtypes and clinical outcomes of this disorder in kidney transplant recipients. METHODS: We retrospectively investigated 34 post-transplant lymphoproliferative disorder patients diagnosed out of the 1210 kidney transplant recipients who had undergone the surgery at the two largest centers in Japan between January 1983 and December 2017. RESULTS: A total of 32 patients (94.1%) developed late-onset post-transplant lymphoproliferative disorder (diagnosed 1 year after transplantation). The cumulative incidence rates were 0.76% and 1.59% at 5 and 10 years post-transplantation, respectively. The central nervous system was the most common site (35.3%, 12/34). Overall survival was similar between patients with and without central nervous system lesions (P = 0.676). Of all of the cases, 23.5% (8/34) were detected through cancer screening. Importantly, patients with screening-detected post-transplant lymphoproliferative disorder had better overall survival than those with the disorder who had been symptom detected (P = 0.0215). Overall survival was significantly reduced in patients who developed the disorder compared with those who did not (P = 0.0001). CONCLUSIONS: Post-transplant lymphoproliferative disorder was more likely to occur in the late post-transplantation period, which showed that long-term medical examination for transplant recipients is required. Based on our findings, we propose vigilant, long-term, cancer screening in kidney transplant recipients.


Assuntos
Transplante de Rim , Transtornos Linfoproliferativos , Humanos , Incidência , Japão/epidemiologia , Transplante de Rim/efeitos adversos , Transtornos Linfoproliferativos/diagnóstico , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/etiologia , Estudos Retrospectivos , Fatores de Risco
11.
EClinicalMedicine ; 43: 101223, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34934934

RESUMO

BACKGROUND: Endogenous molecules that provide an unbiased and a precise evaluation of kidney function are still necessary. We explored the potential of clearance of d-serine, a rare enantiomer of serine and a biomarker of kidney function, as a measure of glomerular filtration rate (GFR). METHODS: This was a cross-sectional observational study of 200 living kidney transplant donors and recipients enrolled between July 2019 and December 2020 in a single Japanese center, for whom GFR was measured by clearance of inulin (C-in). Clearance of d-serine (C-dSer) was calculated based on blood and urine levels of d-serine, as measured by two-dimensional high-performance liquid chromatography. Analytical performance was assessed by calculating biases. Utilizing data from 129 participants, we developed equations for C-in based on C-dSer and C-cre using a linear regression model, and the performance was validated in 68 participants. FINDINGS: The means of C-in and C-dSer were 66.7 and 55.7 mL/min/1.73 m2 of body surface area, respectively, in the entire cohort. C-dSer underestimated C-in with a proportional bias of 22.0% (95% confidence interval, 14.2-29.8%) and a constant bias of -1.24 (-5.78-3.31), whereas the proportional bias was minor to that of C-cre (34.6% [31.1-38.2%] and 2.47 (-1.18-6.13) for proportional and constant bias, respectively). Combination of C-dSer and C-cre measured C-in with an equation of 0.391 × C-dSer + 0.418 × C-cre + 3.852, which reduced the proportional bias (6.5% [-0.2-13.1%] and -4.30 [-8.87-0.28] for proportional and constant bias, respectively). In the validation dataset, this equation performed well with median absolute residual of 3.5 [2.3-4.8], and high ratio of agreement (ratios of 30% and 15% different from C-in [P30 and P15] of 98.5 [91.4-100] and 89.7 [80.0-95.2], respectively). INTERPRETATION: The smaller proportional bias compared to that of C-cre is an advantage of C-dSer as a measure of C-in. Combinational measurement of d-serine and creatinine, two endogenous molecules, has the potential to serve as a measure of GFR with precision and minor biases and can support important clinical decisions. FUNDING: Japan Society for the Promotion of Science (JSPS, grant number 17H04188), Japan Agency of Medical Research and Development (AMED, JP20gm5010001), Osaka Kidney Bank (OKF19-0010), Shiseido Co., Ltd and KAGAMI Inc.

12.
Cancer Med ; 10(7): 2205-2215, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33314709

RESUMO

Kidney transplantation is the most promising treatment to improve mortality and life quality in end-stage kidney disease; however, cancer remains a leading cause of death. Several factors including immunosuppressants might be associated with a gradual increase in cumulative cancer incidence after kidney transplantation. Risk factors for cancer and overall and cancer-specific survival were analyzed in 1973 kidney transplant recipients from three study institutions in Japan. The 5-, 10-, 20-, and 30-year overall and cancer-specific survival rates were 93.3%, 88.4%, 78.0%, and 63.6% and 99.4%, 98.0%, 95.3%, and 91.7%, respectively. The overall survival rate was significantly higher and the graft survival rate was significantly lower in recipients without cancer than in those with cancer. Older recipient age, longer dialysis duration before kidney transplantation, and history of transfusion were significant predictors of cancer. Dialysis duration before kidney transplantation was a prognostic factor of overall survival rate. Regarding cancer-specific survival rates, older recipient age and dialysis duration before kidney transplantation were prognostic factors of worse cancer-specific survival rates. The type of immunosuppressant was not associated with an increased cancer rate. Aggressiveness of immunosuppressant regimens or potent immunosuppressants might improve graft survival rate while inducing de novo cancer after kidney transplantation. Older age and longer dialysis duration before kidney transplantation were risk factors of cancer-specific survival rate.


Assuntos
Transplante de Rim/efeitos adversos , Neoplasias/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Transplantados/estatística & dados numéricos , Adulto , Fatores Etários , Transfusão de Sangue/estatística & dados numéricos , Estudos de Coortes , Feminino , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Imunossupressores/efeitos adversos , Incidência , Japão/epidemiologia , Falência Renal Crônica/cirurgia , Transplante de Rim/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/mortalidade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Análise de Regressão , Diálise Renal/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Doadores de Tecidos
13.
Kidney360 ; 2(10): 1611-1624, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-35372967

RESUMO

Background: d-serine, a long-term undetected enantiomer of serine, is a biomarker that reflects kidney function and disease activity. The physiologic functions of d-serine are unclear. Methods: The dynamics of d-serine were assessed by measuring d-serine in human samples of living kidney donors using two-dimensional high-performance liquid chromatography, and by autoradiographic studies in mice. The effects of d-serine on the kidney were examined by gene expression profiling and metabolic studies using unilateral nephrectomy mice, and genetically modified cells. Results: Unilateral nephrectomy in human living kidney donors decreases urinary excretion and thus increases the blood level of d-serine. d-serine is quickly and dominantly distributed to the kidney on injection in mice, suggesting the kidney is a main target organ. Treatment of d-serine at a low dose promotes the enlargement of remnant kidney in mouse model. Mechanistically, d-serine activates the cell cycle for tissue remodeling through an mTOR-related pathway. Conclusions: d-serine is a physiologic molecule that promotes kidney remodeling. Besides its function as a biomarker, d-serine has a physiologic activity that influences kidney function.


Assuntos
Rim , Serina , Animais , Proliferação de Células , Humanos , Rim/metabolismo , Doadores Vivos , Camundongos , Nefrectomia
14.
Kidney360 ; 2(11): 1734-1742, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-35372995

RESUMO

Background: The diagnosis of diabetic nephropathy (DN), the major cause of ESKD, requires kidney biopsy. d-Serine, present only in trace amounts in humans, is a biomarker for kidney diseases and shows potential to distinguish the origin of kidney diseases, whose diagnoses usually require kidney biopsy. We extended this concept and examined the potential of d-serine in the diagnosis of DN. Methods: We enrolled patients with biopsy sample-proven DN and primary GN (minimal change disease and IgA nephropathy) and participants without kidney disease. A total of 388 participants were included in this study, and d-serine levels in blood and urine were measured using two-dimensional high-performance liquid chromatography, and urinary fractional excretion (FE) of d-serine was calculated. Using data from 259 participants, we developed prediction models for detecting DN by logistic regression analyses, and the models were validated in 129 participants. Results: A d-serine blood level of >2.34 µM demonstrated a high specificity of 83% (95% CI, 70% to 93%) for excluding participants without kidney diseases. In participants with a d-serine blood level >2.34 µM, the threshold of 47% in FE of d-serine provided an optimal threshold for the detection of DN (AUC, 0.85 [95% CI, 0.76 to 0.95]; sensitivity, 79% [95% CI, 61% to 91%]; specificity, 83% [95% CI, 67% to 94%]). This plasma-high and FE-high profile of d-serine in combination with clinical factors (age, sex, eGFR, and albuminuria) correctly predicted DN with a sensitivity of 91% (95% CI, 72% to 99%) and a specificity of 79% (95% CI, 63% to 80%), and outperformed the model based on clinical factors alone in the validation dataset (P<0.02). Conclusions: Analysis of d-serine in blood and urinary excretion is useful in identifying DN in patients undergoing kidney biopsy. Profiling of d-serine in patients with kidney diseases supports the suitable treatment through the auxial diagnosis of the origins of kidney diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Biópsia/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/diagnóstico , Humanos , Rim/patologia , Serina
15.
Nephron ; 144 Suppl 1: 43-48, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33227797

RESUMO

A 64-year-old man with nephrotic syndrome was admitted to another hospital where his renal biopsy revealed membranoproliferative glomerulonephritis (MPGN) with monoclonal immunoglobulin (Ig) G, subclass 1, κ light chain (IgG1κ) deposition on immunofluorescence (IF). Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) was suspected due to monoclonal IgG1κ deposits and the absence of hematological abnormalities. However, the typical PGNMID phenotype was not observed by electron microscopy. Instead, an organized and striated muscle-like structure was observed in the subendothelial space. Since a 2-year treatment with immunosuppressants did not improve his proteinuria, a second biopsy was performed at our hospital. It showed an MPGN-like phenotype; however, monoclonal Ig deposits on IF were no longer observed. One year after the second biopsy, he developed ESRD. Thus, he underwent living kidney transplantation from his wife. Allograft biopsy was performed as proteinuria was observed 3 months after transplantation, which again showed an MPGN-like phenotype with monoclonal IgG1κ deposits. The observed electron-dense deposits were similar to those in the native biopsies. Accordingly, the patient was diagnosed with recurrent MPGN. Adding methylprednisolone pulse therapy to conventional immunosuppressants did not improve the patient's renal function or proteinuria. He died of Legionella pneumonia 8 months after transplantation. Considering the patient's histological findings of MPGN with monoclonal IgG1κ deposits and early recurrence of glomerulonephritis after transplantation, he was diagnosed with PGNMID with novel electron-dense deposits.


Assuntos
Glomerulonefrite Membranoproliferativa/patologia , Imunoglobulina G/análise , Rim/ultraestrutura , Biópsia , Glomerulonefrite Membranoproliferativa/imunologia , Humanos , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Recidiva
16.
Biochem Biophys Res Commun ; 533(4): 698-703, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33131768

RESUMO

Chronic renal failure is exacerbated by oxidative stress, and this condition is difficult to treat in advanced stages. Because of the lack of effective treatments, the disease is a global public health concern. We developed a Si-based agent that continuously generates hydrogen for more than 24 h by reacting with water under conditions similar to those in the gastrointestinal tract. Given the efficacy of hydrogen in the treatment of conditions associated with oxidative stress, we examined whether the Si-based agent had beneficial effects on the development of renal failure. The Si-based agent was orally administered to rats that were developing renal failure. Rats underwent 5/6 nephrectomy to establish a remnant kidney model. Specifically, on day -7, rats underwent right 2/3 nephrectomy, followed by light nephrectomy on day 0. Starting on day -3, the rats were administered a control or Si-based agent-containing diet for 8 weeks. Compared with the findings in control rats, the Si-based agent greatly suppressed the increases of both serum creatinine and urinary protein levels. All analyzed parameters of oxidative stress were significantly suppressed in the Si-based agent groups. Histopathological examination illustrated that glomerular hypertrophy was suppressed by the treatment. Quantitative real-time reverse transcription-polymerase chain reaction revealed that sirtuin 1 and heme oxygenase-1 expression was increased in the Si-based agent groups, suggesting improved antioxidant activity and reduced hypoxia. In addition, caspase-3 and interleukin-6 expression was suppressed in the Si-based agent groups, indicating the alleviation of apoptosis and inflammation. In conclusion, oral administration of a Si-based agent resulted in renoprotective effects, presumably by suppressing oxidative stress via hydrogen generation.


Assuntos
Antioxidantes/farmacologia , Creatinina/sangue , Hidrogênio/farmacologia , Falência Renal Crônica/tratamento farmacológico , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Silício/farmacologia , Administração Oral , Animais , Caspase 3/genética , Caspase 3/metabolismo , Hipóxia Celular , Modelos Animais de Doenças , Regulação para Baixo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hidrogênio/uso terapêutico , Interleucina-6/genética , Interleucina-6/metabolismo , Rim/citologia , Rim/metabolismo , Rim/patologia , Falência Renal Crônica/patologia , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley , Silício/química , Silício/uso terapêutico , Sirtuína 1/genética , Sirtuína 1/metabolismo , Regulação para Cima
17.
Ther Clin Risk Manag ; 16: 947-952, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116544

RESUMO

PURPOSE: BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) is one of the most difficult infections to be treated after kidney transplantation. Although patients with BKPyVAN usually received a reduction of immunosuppressive agents, the majority of these patients undergo the loss of the graft kidney without any effective treatment afterward. Therefore, development of more effective therapy for BKPyVAN is eagerly expected. PATIENTS AND METHODS: Among patients who underwent a kidney transplantation between January 2016 and April 2019 at our hospital, there were five cases of BKPyVAN. After the initial diagnosis, all patients discontinued administration of mycophenolate mofetil (MMF), which was not enough to diminish decoy cells in urine cytology test. Therefore, all patients received additional intravenous immunoglobulin (IVIG) (100 mg/kg/day) therapy for five days and were evaluated for the therapeutic effect of IVIG with immunohistochemical examination using re-biopsy samples of the graft kidney. RESULTS: After IVIG therapy, 2 cases showed negative decoy cells in urine and 3 cases showed a drastic decrease of plasma BK virus load. Importantly, simian virus (SV) 40 large T antigens diminished after IVIG administration in all cases, which degraded polyomavirus nephropathy classification. CONCLUSION: Although it is difficult to treat BKPyVAN after kidney transplant, IVIG therapy was considered to a promising treatment to improve severity of BKPyVAN especially in cases that dose reduction of immunosuppressive agents was ineffective.

18.
Front Med (Lausanne) ; 7: 95, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32266279

RESUMO

Organ ischemia-reperfusion injury (IRI), which is unavoidable in kidney transplantation, induces the formation of reactive oxygen species and causes organ damage. Although the efficacy of molecular hydrogen (H2) in IRI has been reported, oral intake of H2-rich water and inhalation of H2 gas are still not widely used in clinical settings because of the lack of efficiency and difficulty in handling. We successfully generated large quantities of H2 molecules by crushing silicon (Si) to nano-sized Si particles (nano-Si) which were allowed to react with water. The nano-Si or relatively large-sized Si particles (large-Si) were orally administered to rats with renal IRI. Animals were divided into four groups: sham, IRI, IRI + nano-Si, and IRI + large-Si. The levels of serum creatinine and urine protein were significantly decreased 72 h following IRI in rats that were administered nano-Si. The levels of oxidative stress marker, urinary 8-hydroxydeoxyguanosine were also significantly decreased with the nano-Si treatment. Transcriptome and gene ontology enrichment analyses showed that the oral nano-Si intake downregulated the biological processes related to oxidative stress, such as immune response, cytokine production, and extrinsic apoptotic signaling pathway. Alterations in the regulation of a subset of genes in the altered pathways were validated by quantitative polymerase chain reaction. Furthermore, immunohistochemical analysis demonstrated that the nano-Si treatment alleviated interstitial macrophage infiltration and tubular apoptosis, implicating the anti-inflammatory and anti-apoptotic effects of nano-Si. In conclusion, renal IRI was attenuated by the oral administration of nano-Si, which should be considered as a novel H2 administration method.

19.
Transplant Proc ; 51(5): 1362-1364, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31076153

RESUMO

BACKGROUND: Dietary restriction of protein, salt, and energy is recommended to prevent lifestyle related diseases, proteinuria, and graft dysfunction in kidney transplant patients. It is useful if the patients can evaluate meal components by themselves for each meal. PATIENTS AND METHODS: A total of 26 maintenance-phase kidney transplant patients were included in the study. The mean age, sex, body mass index, number of years post-transplantation, creatinine clearance, and 24-hour urinary excretion (24 UE) of protein were recorded on a medical chart. Estimated daily protein and salt oral intake were calculated from 24 UE of nitrogen and sodium, respectively. We compared these laboratory results and patients' self-reported dietary intake using a smartphone-based recipe nutrition calculator (SRNC). RESULTS: Estimated daily protein and salt oral intake calculated from 24 UE of nitrogen and sodium were 55.4 ± 12.9 g/d and 8.5 ± 3.1 g/d, respectively. Estimated daily protein and salt oral intake measured by SRNC were 52.4 ± 13.8 g/day and 6.5 ± .9 g/day, respectively. The results of estimated daily protein and salt oral intake measured by SRNC were correlated to those calculated from 24 UE (R2 = .287 and .217, respectively). CONCLUSIONS: The results of estimated daily protein and salt oral intake measured by SRNC were correlated to those calculated from 24 UE in maintenance-phase kidney transplant patients. SRNC was useful as a measurement modality to evaluate the adherence to dietary guidance. Dietary therapy for these patients may have the potential to improve kidney graft function and survival.


Assuntos
Dieta , Transplante de Rim , Cooperação do Paciente , Autorrelato , Smartphone , Adulto , Proteínas Alimentares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Cloreto de Sódio na Dieta
20.
Transplant Proc ; 51(5): 1481-1487, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31084922

RESUMO

BACKGROUND: Glomerular deposition of IgA1 is a common feature of Henoch-Schönlein purpura nephritis (HSPN) and is indistinguishable from that seen in IgA nephropathy (IgAN). Serum IgA1 is abnormally O-glycosylated in IgA nephropathy, which may contribute to the development of glomerular injury. Abnormal O-glycosylated IgA1 was also detected in HSPN using lectin enzyme-linked immunosorbent assay; however, this method cannot provide the exact structural information of O-glycans. Mass spectrometry is an effective means of quantification of O-glycans, and there is no report to evaluate IgA1 O-glycans in HSPN using mass spectrometry. MATERIALS AND METHODS: We investigated O-glycosylation profile in serum IgA1 from 7 HSPN recipients, 26 IgAN recipients, 25 recipients with other kidney diseases (OKDs), and 26 normal healthy donors using mass spectrometry. RESULTS: Of the 14 GalNac-Gal combinations detected using mass spectrometry, the percentage of the only 6GalNAc-2Gal combination was significantly different between HSPN and IgAN. The percentage of GalNAc 3 in HSPN recipients was significantly higher than that in OKDs recipients and healthy donors (P = .0027 and P < .0001, respectively). Inversely, the percentage of GalNAc 5 in HSPN recipients was significantly lower than that in OKDs recipients and healthy donors (P = .0008, P < .0001, respectively). Moreover, the Gal content and the Gal/GalNAc ratio of HSPN recipients were significantly lower than OKDs recipients and healthy donors. CONCLUSIONS: Examination of Henoch-Schönlein purpura recipients revealed that the number of GalNAc fell and the Gal attachment to GalNAc was reduced compared to other kidney diseases and healthy donors. The IgA1 O-glycosylation profile of HSPN was very similar to that of IgAN.


Assuntos
Vasculite por IgA/metabolismo , Imunoglobulina A/química , Imunoglobulina A/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Acetilgalactosamina/análise , Acetilgalactosamina/metabolismo , Feminino , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite por IGA/patologia , Glicosilação , Humanos , Vasculite por IgA/patologia , Masculino
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