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1.
Discov Med ; 36(183): 799-815, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38665028

RESUMO

BACKGROUND: Calcium oxalate monohydrate (COM) forms the most common type of kidney stones observed in clinics, elevated levels of urinary oxalate being the principal risk factor for such an etiology. The objective of the present study was to evaluate the anti-nephrolithiatic effect of herbo-mineral formulation, Lithom. METHODS: The in vitro biochemical synthesis of COM crystals in the presence of Lithom was performed and observations were made by microscopy and Scanning Electron Microscope (SEM) based analysis for the detection of crystal size and morphology. The phytochemical composition of Lithom was evaluated by Ultra-High-Performance Liquid Chromatography (UHPLC). The in vivo model of Ethylene glycol-induced hyperoxaluria in Sprague-Dawley rats was used for the evaluation of Lithom. The animals were randomly allocated to 5 different groups namely Normal control, Disease control (ethylene glycol (EG), 0.75%, 28 days), Allopurinol (50 mg/kg, q.d.), Lithom (43 mg/kg, b.i.d.), and Lithom (129 mg/kg, b.i.d.). Analysis of crystalluria, oxalate, and citrate levels, oxidative stress parameters (malondialdehyde (MDA), catalase, myeloperoxidase (MPO)), and histopathology by hematoxylin and eosin (H&E) and Von Kossa staining was performed for evaluation of Lithom. RESULTS: The presence of Lithom during COM crystals synthesis significantly reduced the average crystal area, feret's diameter, and area-perimeter ratio, in a dose-dependent manner. SEM analysis revealed that COM crystals synthesized in the presence of 100 and 300 µg/mL of Lithom exhibited a veritable morphological transition from irregular polygons with sharp edges to smoothened smaller cuboid polygons. UHPLC analysis of Lithom revealed the presence of Trigonelline, Bergenin, Xanthosine, Adenosine, Bohoervinone B, Vanillic acid, and Ellagic acid as key phytoconstituents. In EG-induced SD rats, the Lithom-treated group showed a decrease in elevated urinary oxalate levels, oxidative stress, and renal inflammation. Von Kossa staining of kidney tissue also exhibited a marked reduction in crystal depositions in Lithom-treated groups. CONCLUSION: Taken together, Lithom could be a potential clinical-therapeutic alternative for management of nephrolithiasis.


Assuntos
Oxalato de Cálcio , Modelos Animais de Doenças , Hiperoxalúria , Nefrolitíase , Estresse Oxidativo , Ratos Sprague-Dawley , Animais , Oxalato de Cálcio/metabolismo , Oxalato de Cálcio/química , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Nefrolitíase/induzido quimicamente , Nefrolitíase/metabolismo , Nefrolitíase/patologia , Masculino , Cristalização , Etilenoglicol/toxicidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
2.
J Bras Nefrol ; 46(1): 99-106, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38427579

RESUMO

We present a case of a 69-year-old man who presented for routine check-up and was incidentally found to have kidney failure with an initially unrevealing history and bland urinary sediment. He was diagnosed with oxalate nephropathy in the setting of chronic turmeric supplementation and chronic antibiotic therapy with associated diarrhea. Our case provides several key insights into oxalate nephropathy. First, the diagnosis requires a high index of clinical suspicion. It is uncommonly suspected clinically unless there is an obvious clue in the history such as Roux-en-Y gastric bypass or ethylene glycol poisoning. Diagnosis can be confirmed by histopathologic findings and corroborated by serum levels of oxalate and 24-hour urinary excretion. Second, the diagnosis can often be missed by the pathologist because of the characteristics of the crystals unless the renal pathologist has made it a rule to examine routinely all H&E sections under polarized light. This must be done on H&E, as the other stains dissolve the crystals. Third, one oxalate crystal in a routine needle biopsy is considered pathologic and potentially contributing to the AKI or to the CKD in an important way. Fourth, secondary oxalosis can be largely mitigated or prevented in many cases, especially iatrogenic cases. This can come through the surgeon or the gastroenterologist providing proper instructions to patients on an oxalate-restricted diet or other specific dietary measures. Lastly, this case highlights the success that results from cooperation and communication between the pathologist and the treating physician.


Assuntos
Hiperoxalúria , Insuficiência Renal , Masculino , Humanos , Idoso , Curcuma , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/complicações , Insuficiência Renal/complicações , Oxalatos , Suplementos Nutricionais/efeitos adversos
5.
Urolithiasis ; 49(2): 95-122, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33484322

RESUMO

Urolithiasis is one of the oldest diseases affecting humans, while plants are one of our oldest companions providing food, shelter, and medicine. In spite of substantial progress in understanding the pathophysiological mechanisms, treatment options are still limited, often expensive for common people in most parts of the world. As a result, there is a great interest in herbal remedies for the treatment of urinary stone disease as an alternative or adjunct therapy. Numerous in vivo and in vitro studies have been carried out to understand the efficacy of herbs in reducing stone formation. We adopted PRISMA guidelines and systematically reviewed PubMed/Medline for the literature, reporting results of various herbal products on in vivo models of nephrolithiasis/urolithiasis. The Medical Subject Heading Terms (Mesh term) "Urolithiasis" was used with Boolean operator "AND" and other related Mesh Unique terms to search all the available records (July 2019). A total of 163 original articles on in vivo experiments were retrieved from PubMed indexed with the (MeshTerm) "Urolithiasis" AND "Complementary Therapies/Alternative Medicine, "Urolithiasis" AND "Plant Extracts" and "Urolithiasis" AND "Traditional Medicine". Most of the studies used ethylene glycol (EG) to induce hyperoxaluria and nephrolithiasis in rats. A variety of extraction methods including aqueous, alcoholic, hydro-alcoholic of various plant parts ranging from root bark to fruits and seeds, or a combination thereof, were utilized. All the investigations did not study all aspects of nephrolithiasis making it difficult to compare the efficacy of various treatments. Changes in the lithogenic factors and a reduction in calcium oxalate (CaOx) crystal deposition in the kidneys were, however, considered favorable outcomes of the various treatments. Less than 10% of the studies examined antioxidant and diuretic activities of the herbal treatments and concluded that their antiurolithic activities were a result of antioxidant, anti-inflammatory, and/or diuretic effects of the treatments.


Assuntos
Hiperoxalúria/tratamento farmacológico , Rim/efeitos dos fármacos , Nefrolitíase/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Oxalato de Cálcio/química , Oxalato de Cálcio/urina , Cristalização , Modelos Animais de Doenças , Diuréticos/farmacologia , Diuréticos/uso terapêutico , Etilenoglicol/administração & dosagem , Etilenoglicol/toxicidade , Humanos , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/complicações , Hiperoxalúria/diagnóstico , Rim/química , Rim/patologia , Medicina Tradicional/métodos , Nefrolitíase/induzido quimicamente , Nefrolitíase/patologia , Nefrolitíase/urina , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar
6.
J Investig Med High Impact Case Rep ; 8: 2324709620963635, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33019829

RESUMO

As COVID-19 (coronavirus disease 2019) spreads across the world multiple therapeutic interventions have been tried to reduce morbidity and mortality. We describe a case of collapsing focal sclerosing glomerulosclerosis (FSGS) and acute oxalate nephropathy in a patient treated with high-dose intravenous vitamin C for severe COVID-19 infection. Collapsing FSGS has been described in patients with COVID-19 infection associated with APOL-1; however, this case had collapsing FSGS developing in low-risk heterozygous APOL-1 variant, and we postulate that the intensity of the COVID-19 cytokine storm overwhelmed the protective state of APOL-1 heterozygosity. This case illustrates the importance of assessing the risk and benefit of planned therapeutic interventions on a case-by-case basis especially when there are still so many unknowns in the management of COVID-19 infection. Strong consideration should be given for performing a renal biopsy in patients who develop multifactorial acute kidney injury.


Assuntos
Ácido Ascórbico/efeitos adversos , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/induzido quimicamente , Hiperoxalúria/induzido quimicamente , Glomérulos Renais/patologia , Oxalatos/metabolismo , Pneumonia Viral/tratamento farmacológico , Doença Aguda , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Ácido Ascórbico/administração & dosagem , Biópsia , COVID-19 , Infecções por Coronavirus/epidemiologia , Progressão da Doença , Glomerulosclerose Segmentar e Focal/diagnóstico , Humanos , Hiperoxalúria/diagnóstico , Hiperoxalúria/metabolismo , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos
7.
BMJ Case Rep ; 12(11)2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31748360

RESUMO

Oxalate kidney injury can manifest as oxalate nephropathy or nephrolithiasis and present as acute kidney injury or even as end-stage renal disease. There are several known causes for acute oxalate nephropathy; however, the combination of exocrine pancreatic insufficiency with overconsumption of vitamin C has not been described before. In this case, a man in his early 80s presented with anorexia and extreme fatigue for 1 week. He had a history of myalgic encephalomyelitis, also known as chronic fatigue syndrome, for which he took several supplements, including high doses of vitamin C. Furthermore, several years ago, he was diagnosed elsewhere with exocrine pancreatic insufficiency. On admission, acute kidney injury was diagnosed. The kidney biopsy showed oxalate nephropathy as the cause. We diagnosed acute oxalate nephropathy due to high vitamin C doses and exocrine pancreatic insufficiency. Within 14 days, his kidney function got worse and he required renal replacement therapy.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Ácido Ascórbico/efeitos adversos , Insuficiência Pancreática Exócrina/complicações , Hiperoxalúria/induzido quimicamente , Rim/patologia , Doença Aguda , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/fisiopatologia , Idoso de 80 Anos ou mais , Humanos , Hiperoxalúria/complicações , Rim/metabolismo , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Oxalatos/efeitos adversos , Terapia de Substituição Renal/métodos
8.
Am J Kidney Dis ; 74(3): 417-420, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30910370

RESUMO

We report a case of systemic oxalosis involving the eyes and joints due to long-term use of high-dose vitamin C in a patient receiving maintenance peritoneal dialysis (PD). This 76-year-old woman with autosomal dominant polycystic kidney disease underwent living unrelated kidney transplantation 10 years earlier. The transplant failed 6 months before presentation, and she initiated hemodialysis therapy before transitioning to PD therapy 4 months later. During the month before presentation, the patient noted worsening arthralgias and decreased vision. Ophthalmologic examination revealed proliferative retinopathy and calcium oxalate crystals. Plasma oxalate level was markedly elevated at 187 (reference range, <1.7) µmol/L, and urine oxalate-creatinine ratio was high (0.18mg/mg). The patient reported taking up to 4g of vitamin C per day for several years. Workup for causes of primary and secondary hyperoxaluria was otherwise negative. Vitamin C use was discontinued, and the patient transitioned to daily hemodialysis for 2 weeks. Plasma oxalate level before the dialysis session decreased but remained higher (30-53µmol/L) than typical for dialysis patients. Upon discharge, the patient remained on thrice-weekly hemodialysis therapy with stabilized vision and improved joint symptoms. This case highlights the risk of high-dose vitamin C use in patients with advanced chronic kidney disease, especially when maintained on PD therapy.


Assuntos
Ácido Ascórbico , Oxalato de Cálcio , Hiperoxalúria , Falência Renal Crônica/terapia , Diálise Peritoneal/métodos , Doenças Retinianas , Idoso , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/efeitos adversos , Oxalato de Cálcio/análise , Oxalato de Cálcio/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Hiperoxalúria/sangue , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/terapia , Falência Renal Crônica/etiologia , Falência Renal Crônica/cirurgia , Rim Policístico Autossômico Dominante/complicações , Doenças Retinianas/diagnóstico por imagem , Doenças Retinianas/etiologia , Doenças Retinianas/terapia , Resultado do Tratamento , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos , Suspensão de Tratamento
9.
Urolithiasis ; 47(2): 171-179, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29947992

RESUMO

Hyperoxaluria is characterized by an increased excretion of urinary oxalate which is caused by inherited disorders or high oxalate intake leading to renal stone ailment. Until date, reactive oxygen species and inflammation has been convicted for the progression of kidney stones for which antioxidant therapy has been employed. However, recent studies have linked the association of endoplasmic reticulum stress and oxidative imbalance in the progression of renal diseases. Considering oxidative stress being at forefront in causing hyperoxaluric consequences, current study was designed to correlate the impact of hyperoxaluria and regulation of oxidative imbalance via inhibition of endoplasmic reticulum stress by 4-phenylbutyric acid (4-PBA). Male wistar rats were subdivided into three groups, i.e., normal control (C), hyperoxaluric rats given ethylene glycol (EG), and hyperoxaluric rats treated with 4-PBA (EG + PBA). After 28 days of treatment, assessment of antioxidant defence system, inflammation, ER stress, and subsequent unfolded protein response was studied in renal tissue. It was found that the hyperoxaluric insult led to a marked damage to the renal tissue resulting in compromised antioxidant levels, upregulation of ER stress markers along with a steep surge in the extent of inflammation. However, 4-PBA treatment significantly curtailed the deleterious effects of hyperoxaluria by lowering down the level of stress markers as well as normalizing the antioxidant defence enzymes. Therefore, chemical chaperones can be deemed as a new class of drugs for the treatment of hyperoxaluric induced renal damage.


Assuntos
Hiperoxalúria/complicações , Cálculos Renais/prevenção & controle , Rim/efeitos dos fármacos , Fenilbutiratos/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Animais , Biomarcadores/análise , Oxalato de Cálcio/urina , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Etilenoglicol/toxicidade , Humanos , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/urina , Rim/patologia , Rim/fisiopatologia , Cálculos Renais/etiologia , Cálculos Renais/fisiopatologia , Cálculos Renais/urina , Masculino , Fenilbutiratos/uso terapêutico , Ratos , Ratos Wistar
10.
Chem Biol Interact ; 252: 36-46, 2016 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-27018375

RESUMO

The study explores calcium oxalate crystal inhibiting characteristic of polyacrylic acid (pAA), an anionic polymer in in vitro and in vivo. Animals were divided into 5 groups where group 1 served as control, group 2 were made hyperoxaluric by supplementing with Ethylene glycol (EG) 0.75% (v/v) for 30 days. Group 3, 4 & 5 were also given with EG and treated simultaneously with 2.5, 5 & 10 mg of pAA/kg of body weight, respectively. Urine, serum and tissue analyses along with histological studies were performed at the end of the 30 days study. In vitro crystallization was significantly inhibited by pAA and further it was supported by particle size analyses, XRD and FT-IR studies. Toxicological analyses showed that pAA was safe to use in animals at concentrations below 100 mg/kg BW. In vivo anti-urolithic study showed significant improvement in urinary lithogenic factors (calcium, oxalate, phosphate, citrate & magnesium) and renal function parameters (creatinine, urea and protein). Tissue analyses on anti-oxidant enzyme activity and lipid peroxides showed maintenance of tissue antioxidant status in the pAA supplemented rats and histological studies demonstrated the nephroprotection offered by pAA and were concurrent to the biochemical analyses. Supplementation of pAA not only reduces the crystal aggregation but also regulates the expression and localization of crystal inhibiting proteins and gene expression of inflammatory cytokines in experimental animals. In summary, pAA is a potent anti-urolithic agent in rats and we can propose that 10 mg/kg body weight is the effective dosage of pAA and this concentration can be used for further studies.


Assuntos
Resinas Acrílicas/uso terapêutico , Oxalato de Cálcio/metabolismo , Hiperoxalúria/tratamento farmacológico , Urolitíase/tratamento farmacológico , Resinas Acrílicas/toxicidade , Animais , Oxalato de Cálcio/urina , Etilenoglicol , Feminino , Hiperoxalúria/sangue , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/urina , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos Wistar , Urolitíase/sangue , Urolitíase/induzido quimicamente , Urolitíase/urina
11.
Saudi J Kidney Dis Transpl ; 25(1): 113-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24434393

RESUMO

Renal oxalate deposition can be seen with primary hyperoxaluria, malabsorptive states, ethylene glycol toxicity and, rarely, with excessive vitamin C ingestion. We report a case of secondary hyperoxaluria in which the diagnosis was not considered initially because there was no past history of urinary calculi and no evidence of nephrocalcinosis on plain X-ray of the abdomen and ultrasonography. The disease was detected and diagnosed only after kidney transplantation. Secondary oxalosis can cause graft loss or delayed graft function. Biopsy of the allograft should be carefully examined for oxalate deposits even in the absence of a family history. When oxalosis is diagnosed, intensifying hemodialysis (HD) to eliminate calcium oxalate can help in the recovery of renal function in some cases. Systematic vitamin C supplementation in HD patients should be avoided as it can be a cause of secondary oxalosis.


Assuntos
Ácido Ascórbico/efeitos adversos , Hiperoxalúria/induzido quimicamente , Falência Renal Crônica/terapia , Transplante de Rim , Rim/efeitos dos fármacos , Diálise Renal , Adulto , Biópsia , Feminino , Humanos , Hiperoxalúria/diagnóstico , Hiperoxalúria/fisiopatologia , Hiperoxalúria/terapia , Rim/patologia , Rim/fisiopatologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/cirurgia , Diálise Renal/efeitos adversos , Resultado do Tratamento
12.
Am J Kidney Dis ; 61(6): 1032-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23548555

RESUMO

Oxalate nephropathy is a rare condition characterized by extensive calcium oxalate deposition in the renal tubules, resulting in kidney injury. There are primary forms of the disease that arise from genetic mutation causing overproduction of oxalate. More commonly, this condition is seen as a secondary phenomenon. The clinical presentation is nonspecific, with acute kidney injury and normal serologic study results. The characteristic finding on kidney biopsy is the presence of acute tubular injury associated with polarizable crystals in the tubular lumen and epithelial cytoplasm. We present a case of acute oxalate nephropathy in a patient with underlying systemic lupus erythematosus who recently received intravenous vitamin C.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Ácido Ascórbico/efeitos adversos , Hiperoxalúria/induzido quimicamente , Vitaminas/efeitos adversos , Administração Intravenosa , Terapias Complementares/efeitos adversos , Feminino , Humanos , Lúpus Eritematoso Sistêmico , Pessoa de Meia-Idade
13.
Pharm Biol ; 49(12): 1224-33, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21846174

RESUMO

INTRODUCTION: Boerhaavia diffusa Linn. (Nyctaginaceae) is widely used in traditional Indian medicines against renal afflictions including calcium oxalate (CaOx) urolithiasis and is known for antioxidant activity. OBJECTIVE: The present study was designed to investigate the ameliorating effect of aqueous extract of B. diffusa roots (BDE) in hyperoxaluric oxidative stress and renal cell injury. MATERIAL AND METHODS: In vitro antioxidant activity of BDE was estimated in terms of total phenolic content and 1,1-diphenyl-2-picryl hydrazyl free radical scavenging activity. Wistar albino rats were given 0.75% v/v ethylene glycol in drinking water to induce chronic hyperoxaluria and simultaneously BDE was given to nephrolithiasic treated rats at the dose of 100 and 200 mg/kg b.w. orally for 28 days. Urinary volume, oxalate, serum creatinine, blood urea nitrogen (BUN), malondialdehyde (MDA) and antioxidant enzyme (SOD, CAT, GST, GPx) were evaluated. RESULTS AND DISCUSSION: BDE extract was found to posses a high total phenolic content and exhibited significant free radicals scavenging activity. Oxalate excretion significantly increased in hyperoxaluric animals as compared to control which was protected in BDE-treated animals. BDE treatment significantly reduced level of MDA and improved the activity of antioxidant enzymes followed by reduction in BUN and serum creatinine. In addition, BDE reduced the number of CaOx monohydrate crystals in the urine. Histological analysis depicted that BDE treatment inhibited deposition of CaOx crystal and renal cell damage. CONCLUSION: The present study reveals that antioxidant activity of BDE significantly protects against hyperoxaluric oxidative stress and renal cell injury in urolithiasis.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Hiperoxalúria/tratamento farmacológico , Nyctaginaceae/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/patologia , Animais , Antioxidantes/metabolismo , Compostos de Bifenilo , Catalase/metabolismo , Cromatografia em Camada Fina , Etilenoglicol , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Hiperoxalúria/induzido quimicamente , Rim/patologia , Testes de Função Renal , Masculino , Malondialdeído/metabolismo , Ácido Oxálico/metabolismo , Picratos , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Água
14.
Urol Res ; 39(5): 373-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21373921

RESUMO

The use of hydroxyproline (HP) to generate hyperoxaluria in the rat is a problem because it is impossible to separate the effect of oxalate on renal injury from the effects of HP and the large array of metabolic intermediates formed when HP is converted to oxalate. Previously, the Dahl salt-sensitive (SS) and Brown Norway (BN) rat strains were studied to determine genetic control of resistance or susceptibility to HP-induced renal injury and crystal deposition. To develop a better model to induce hyperoxaluria without causing injury from HP metabolites, animals were fed a diet containing various levels of added oxalate (0, 1, 2, 3, or 5%). After 5 weeks rats were killed and the kidneys were removed for microscopic evaluation of tubule changes and crystal deposition. The 3 and 5% oxalate-fed groups had a substantial increase in urine oxalate, about 50 and 140 µmol/g body weight over controls, respectively. Both the SS and BN 3% oxalate-fed animals showed only slightly elevated tubule area and no crystal deposition. However, BN animals fed 5% oxalate had a dramatic increase in their percent tubule areas compared to control BN rats and treated SS rats. Crystal deposition in the kidneys was only observed in the 5% oxalate-fed groups. The BN kidneys demonstrated a threefold higher crystal deposition compared to oxalate-fed SS rats. We conclude that oxalate-supplemented food is a better method of producing hyperoxaluria in the rat than using HP which may introduce metabolic intermediates injurious to the kidney.


Assuntos
Hiperoxalúria/induzido quimicamente , Animais , Cristalização , Modelos Animais de Doenças , Hidroxiprolina/administração & dosagem , Hidroxiprolina/toxicidade , Hiperoxalúria/metabolismo , Hiperoxalúria/patologia , Hiperoxalúria/urina , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Ácido Oxálico/administração & dosagem , Ácido Oxálico/toxicidade , Ácido Oxálico/urina , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Dahl
15.
Food Chem Toxicol ; 48(4): 1013-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20079795

RESUMO

UNLABELLED: This study investigated the protective effect of the hydro-alcoholic extract of roots of Rubia cordifolia Linn. (HARC) against ethylene glycol induced urolithiasis and its possible underlying mechanisms using male Wistar albino rats. Ethylene glycol feeding resulted in hyperoxaluria, hypocalciuria as well as increased renal excretion of phosphate. Supplementation with HARC significantly prevented change in urinary calcium, oxalate and phosphate excretion dose-dependently. The increased calcium and oxalate levels and number of calcium oxalate crystals deposits in the kidney tissue of calculogenic rats were significantly reverted by HARC treatment. The HARC supplementation also prevents the impairment of renal functions. RESULTS: Indicate that the HARC can protect against ethylene glycol induced urolithiasis as it reduced and prevented the growth of urinary stones. Therefore, HARC is helpful to prevent the recurrence of the disease as it showed its effect on early stages of stone development. The mechanism underlying this effect is mediated possibly through an antioxidant, nephroprotection and its effect on the urinary concentration of stone-forming constituents and risk factors.


Assuntos
Antioxidantes/farmacologia , Etilenoglicol/toxicidade , Extratos Vegetais/farmacologia , Rubia/química , Urolitíase/prevenção & controle , Animais , Cálcio/urina , Modelos Animais de Doenças , Etanol/química , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/prevenção & controle , Rim/efeitos dos fármacos , Rim/patologia , Rim/fisiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxalatos/metabolismo , Raízes de Plantas/química , Ratos , Ratos Wistar , Urinálise , Micção/efeitos dos fármacos , Urolitíase/induzido quimicamente , Urolitíase/patologia , Água/química
16.
Am J Physiol Renal Physiol ; 296(1): F34-45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18799548

RESUMO

Vitamin E was previously reported to reduce calcium oxalate (CaOx) crystal formation. This study explored whether vitamin E deficiency affects intrarenal oxidative stress and accelerates crystal deposition in hyperoxaluria. The control (C) group of rats received a standard diet and drinking water, while the experimental groups received 0.75% ethylene glycol (EG) in drinking water for 42 days. Of the latter, one group received a standard diet (EG group), one received a low-vitamin E (LE) diet (EG+LE group), and the last received an LE diet with vitamin E supplement (4 mg) (EG+LE+E group). The C+LE and C+LE+E groups were the specific controls for the last two experimental groups, respectively. In a separate experiment, EG and EG+LE rats were studied on days 3-42 to examine the temporal relationship between oxidative change and crystal formation. Urinary biochemistry and activity/levels of antioxidative and oxidative enzymes in glomeruli and tubulointerstitial specimens (TIS) were examined. In EG rats, CaOx crystal accumulation was associated with low antioxidative enzyme activity in TIS and with increased oxidative enzyme expression in glomeruli. In the EG+LE group, marked changes in antioxidative and oxidative enzyme levels were seen and correlated with massive CaOx deposition and tubular damage. The increased oxidative stress seen with EG+LE treatment was largely reversed by vitamin E supplementation. A temporal study showed that decrease in antioxidative defense and increased free radical formation in the EG+LE group occurred before crystal deposition. This study shows that low vitamin E disrupts the redox balance and causes cell death, thereby favoring crystal formation.


Assuntos
Oxalato de Cálcio/metabolismo , Hiperoxalúria/metabolismo , Rim/metabolismo , Estresse Oxidativo/fisiologia , Deficiência de Vitamina E/metabolismo , Animais , Cristalização , Suplementos Nutricionais , Modelos Animais de Doenças , Etilenoglicol , Radicais Livres/metabolismo , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/fisiopatologia , Rim/fisiopatologia , Masculino , Glicoproteínas de Membrana/metabolismo , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxidos/metabolismo , Vitamina E/metabolismo , Vitamina E/farmacologia , Xantina Oxidase/metabolismo
17.
Am J Physiol Renal Physiol ; 295(2): F388-96, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18448592

RESUMO

Hyperoxaluric kidneys show an impaired diuretic response to acute infusion of L-arginine. In this study, we examined the chronic effect of l-arginine supplementation on CaOx crystal formation in hyperoxaluric rat kidneys. Eight groups were tested: control (received drinking water), L group (received L-arginine, 0.6%), LN group [received NG-nitro-L-arginine methyl ester (L-NAME, 10 mg/kg)], L + LN group (received L-arginine + l-NAME), HP group [received hydroxyl-L-proline (HP, 5%) mixed with chow to induce hyperoxaluria], L + HP group (received HP + L-arginine), HP + LN group, and L + HP + LN group. The duration was 42 days, and each group had eight animals. Urinary biochemistry and renal CaOx amounts were measured, as well as renal expressions of nitric oxide synthase (NOS) isoforms and NAD(P)H oxidase. The distribution of inducible NOS (iNOS), NAD(P)H oxidase, ED1-positive cells, and nitrotyrosine was examined by immunohistochemical and immunofluorescence studies, whereas superoxide production from the kidneys was examined by fluorescence spectrometric assay. Compared with the HP group, the L + HP group had excessive CaOx crystal accumulation and enhanced endothelial NOS (eNOS), iNOS, and NAD(P)H oxidase protein expression in the kidney. Urinary excretion of nitrotyrosine was markedly increased. Increased superoxide formation in the L + HP kidney was derived from NAD(P)H oxidase and uncoupled eNOS, and increased nitrotyrosine formation might derive from iNOS and ED1-positive cells that gathered around the CaOx crystals. L-NAME cotreatment (L + HP + LN group) reduced renal oxidative nitrosative stress and tubular damage, which were induced by L + HP. The results showed that chronic l-arginine treatment to the hyperoxaluric kidney with massive CaOx crystal deposition may have a toxic effect by enhancing intrarenal oxidative and nitrosative stress.


Assuntos
Arginina/farmacologia , Oxalato de Cálcio/metabolismo , Hiperoxalúria/metabolismo , Rim/metabolismo , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Arginina/administração & dosagem , Cristalização , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Hidroxiprolina , Hiperoxalúria/induzido quimicamente , Rim/efeitos dos fármacos , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
18.
J Urol ; 178(5): 2191-6, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17870111

RESUMO

PURPOSE: Patients with calcium oxalate kidney stones are advised to decrease the consumption of foods that contain oxalate. We hypothesized that a cutback in dietary oxalate would lead to a decrease in the urinary excretion of oxalate and decreased stone recurrence. We tested the hypothesis in an animal model of calcium oxalate nephrolithiasis. MATERIALS AND METHODS: Hydroxy-L-proline (5%), a precursor of oxalate found in collagenous foods, was given with rat chow to male Sprague-Dawley rats. After 42 days rats in group 1 continued on hydroxy-L-proline, while those in group 2 were given chow without added hydroxy-L-proline for the next 21 days. Food and water consumption as well as weight were monitored regularly. Once weekly urine was collected and analyzed for creatinine, calcium, oxalate, lactate dehydrogenase, 8-isoprostane and H(2)O(2). Urinary pH and crystalluria were monitored. Rats were sacrificed at 28, 42 and 63 days, respectively. Renal tissue was examined for crystal deposition by light microscopy. RESULTS: Rats receiving hydroxy-L-proline showed hyperoxaluria, calcium oxalate crystalluria and nephrolithiasis, and by day 42 all contained renal calcium oxalate crystal deposits. Urinary excretion of lactate dehydrogenase, 8-isoprostane and H(2)O(2) increased significantly. After hydroxy-L-proline was discontinued in group 2 there was a significant decrease in urinary oxalate, 8-isoprostane and H(2)O(2). Half of the group 2 rats appeared to be crystal-free. CONCLUSIONS: Dietary sources of oxalate can induce hyperoxaluria and crystal deposition in the kidneys with associated degradation in renal biology. Eliminating oxalate from the diet decreases not only urinary oxalate, but also calcium oxalate crystal deposits in the kidneys and improves their function.


Assuntos
Oxalato de Cálcio/toxicidade , Suplementos Nutricionais/toxicidade , Hidroxiprolina/toxicidade , Nefrolitíase/urina , Animais , Oxalato de Cálcio/farmacocinética , Creatinina/urina , Modelos Animais de Doenças , Seguimentos , Concentração de Íons de Hidrogênio , Hidroxiprolina/farmacocinética , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/urina , Rim/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Nefrolitíase/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Urina/química
19.
Hum Exp Toxicol ; 26(12): 923-32, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18375635

RESUMO

Kidney stones are known to haunt humanity for centuries and increase in oxalate is a predominant risk factor for stone formation. The present study was initiated with a notion to study the oxidative and nitrosative stress on erythrocytes under oxalate stress and the putative role of sulphated polysaccharides. Hyperoxaluria was induced in two groups by the administration of 0.75% ethylene glycol in drinking water for 28 days and one of them was treated with sulphated polysaccharides from Fucus vesiculosus from the 8th day to the end of the experimental period of 28 days at a dose of 5 mg/kg body weight subcutaneously. Control and drug control (sulphated polysaccharides alone) were also included in the study. Glycolic and glyoxylic acid levels of urine were analyzed as an index of hyperoxaluria. The plasma enzymic markers of cellular integrity, redox status of red blood cells, osmotic fragility, and (14)C-oxalate binding were investigated. Urine and plasma nitric oxide metabolites, expression of inducible nitric oxide synthase protein, and mRNA were assessed in kidney to evaluate the nitrosative stress. Increased levels of glycolic and glyoxylic acid in urine indicated the prevalence of hyperoxaluria in ethylene glycol-administered groups. Plasma aspartate and alanine transaminase were not altered, but alkaline phosphatase and lactate dehydrogenase of hyperoxaluric group were increased indicating tissue damage. Activities of antioxidant enzymes were decreased, whereas erythrocyte membrane lipid peroxidation was increased in hyperoxaluric rats. Moreover, an altered fragility with an increase in oxalate binding activity was observed in hyperoxaluric group. Increase in nitric oxide metabolites levels in urine and plasma along with an increase in expression of inducible nitric oxide synthase protein and mRNA in kidney were observed in hyperoxaluric rats. Administration of sulphated polysaccharides to hyperoxaluric rats averted the abnormal increase in urinary glycolic and glyoxylic acid levels and enzyme activities, decreased lipid peroxidation, and increased the activities of antioxidant enzymes. Furthermore, increased nitrosative stress accompanying hyperoxaluria was also normalized on sulphated polysaccharides treatment. To conclude, sulphated polysaccharide administration was able to maintain the integrity of erythrocyte membrane and decrease the damage to erythrocytes in hyperoxaluria.


Assuntos
Eritrócitos/efeitos dos fármacos , Fucus/química , Hiperoxalúria/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/uso terapêutico , Animais , Biomarcadores/metabolismo , Radioisótopos de Carbono , Modelos Animais de Doenças , Eritrócitos/enzimologia , Eritrócitos/patologia , Etilenoglicol/toxicidade , Glicolatos/urina , Glioxilatos/urina , Hiperoxalúria/sangue , Hiperoxalúria/induzido quimicamente , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Doadores de Óxido Nítrico , Nitrosação , Fragilidade Osmótica/efeitos dos fármacos , Oxalatos/metabolismo , Estresse Oxidativo/fisiologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Sulfatos
20.
J Ethnopharmacol ; 105(1-2): 306-11, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16386862

RESUMO

In India, drumstick (Moringa oleifera Lam. (Moringaceae)) is commonly used as a phytotherapeutic agent. The effect of oral administration of aqueous and alcoholic extract of Moringa oleifera root-wood on calcium oxalate urolithiasis has been studied in male Wistar albino rats. Ethylene glycol feeding resulted in hyperoxaluria as well as increased renal excretion of calcium and phosphate. Supplementation with aqueous and alcoholic extract of Moringa oleifera root-wood significantly reduced the elevated urinary oxalate, showing a regulatory action on endogenous oxalate synthesis. The increased deposition of stone forming constituents in the kidneys of calculogenic rats was also significantly lowered by curative and preventive treatment using aqueous and alcoholic extracts. The results indicate that the root-wood of Moringa oleifera is endowed with antiurolithiatic activity.


Assuntos
Etilenoglicol/toxicidade , Moringa oleifera/química , Raízes de Plantas/química , Urolitíase/tratamento farmacológico , Madeira , Animais , Feminino , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/complicações , Masculino , Ratos , Ratos Wistar , Urolitíase/etiologia
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