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1.
PLoS One ; 9(4): e93056, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24691130

RESUMO

Oxalate toxicity is mediated through generation of reactive oxygen species (ROS) via a process that is partly dependent on mitochondrial dysfunction. Here, we investigated whether C-phycocyanin (CP) could protect against oxidative stress-mediated intracellular damage triggered by oxalate in MDCK cells. DCFDA, a fluorescence-based probe and hexanoyl-lysine adduct (HEL), an oxidative stress marker were used to investigate the effect of CP on oxalate-induced ROS production and membrane lipid peroxidation (LPO). The role of CP against oxalate-induced oxidative stress was studied by the evaluation of mitochondrial membrane potential by JC1 fluorescein staining, quantification of ATP synthesis and stress-induced MAP kinases (JNK/SAPK and ERK1/2). Our results revealed that oxalate-induced cells show markedly increased ROS levels and HEL protein expression that were significantly decreased following pre-treatment with CP. Further, JC1 staining showed that CP pre-treatment conferred significant protection from mitochondrial membrane permeability and increased ATP production in CP-treated cells than oxalate-alone-treated cells. In addition, CP treated cells significantly decreased the expression of phosphorylated JNK/SAPK and ERK1/2 as compared to oxalate-alone-treated cells. We concluded that CP could be used as a potential free radical-scavenging therapeutic strategy against oxidative stress-associated diseases including urolithiasis.


Assuntos
Citoproteção/efeitos dos fármacos , Mitocôndrias/patologia , Oxalatos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Ficocianina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Cães , Ativação Enzimática/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Células Madin Darby de Rim Canino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo
2.
Clin Exp Nephrol ; 11(3): 196-201, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17891345

RESUMO

BACKGROUND: This study was done to investigate the DNA binding ability of a diagnostic biomarker, 45-kDa calcium oxalate monohydrate (COM) binding protein, isolated from human kidney and its effect on transcription. METHODS: The 45-kDa COM binding protein was isolated and purified from human kidney. The subcellular localization of the protein and the amino acid composition of the protein were analyzed. Oxalate-binding activity in the presence or absence of DNA was determined. The possibility of forming DNA-protein adducts was checked by diethylaminoethyl (DEAE)-Sephadex column chromatography. The effect of the protein on in vitro transcription was also studied. RESULTS: The isolated 45-kDa protein was found to be basic in nature and its AACompIdent analysis showed it to be related to known transcription factors. The protein was found to be present in kidney cytosol and nucleus. The decreased oxalate binding activity in the presence of the DNA, and the shift in the DEAE-Sephadex elution profile established the DNA-binding ability of the protein. The in vitro transcription assay demonstrated the repression effect of the protein on gene expression during hyperoxaluria. CONCLUSIONS: Transcriptional repression by the 45-kDa COM binding protein in an in vitro transcription assay system was reduced in the presence of oxalate. Hence, altered expression of certain genes involved in the prognosis of urolithiasis might be mediated by this 45-kDa protein.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas Repressoras/química , Transcrição Gênica/efeitos dos fármacos , Biomarcadores/química , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/farmacologia , Humanos , Rim/química , Proteínas Repressoras/isolamento & purificação , Proteínas Repressoras/farmacologia
3.
Clin Nutr ; 24(6): 932-42, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16084629

RESUMO

BACKGROUND: High Spirulina diet is a potential risk factor for nephrolithiasis since it has the capacity to increase urinary oxalate and uric acid level, facilitating lithogenesis. Our aim was to identify the effect of Spirulina diet during hyperoxaluric condition in Wistar albino rats. METHODS: The animals were divided into four groups: control (Gl, n=6); ethylene glycol (EG) induced (G2, n=6); EG+Spirulina (G3, n=6); Spirulina alone (G4, n=6). EG at 0.75% was administered to G2 and G3 through drinking water for 4 weeks and Spirulina 1500 mg/kg feed was administered to G3 and G4. RESULTS: Urinary parameters like oxalate, uric acid, calcium, urea, and creatinine (P<0.001) were found increased after Spirulina diet under hyperoxaluric conditions compared to the same without Spirulina diet. Similarly the BUN, plasma contents of uric acid, urea, creatinine (P<0.001) were found to be raised in G3. The renal and RBC GSH levels, as estimated by HPLC, seemed decreased when compared to G2. CONCLUSIONS: The present study shows that free radicals aid in the progression of nephrolithiasis. The crystal deposition was found to be high in the renal cells of G3 than G2 and TEM revealed damage in renal cell of G3 implying that the disease deteriorates by free radical injury. In contrast the Spirulina diet alone (G4) did not induce any features relating to stone forming condition suggesting that free radical release might have been suppressed due to enrichment of dietary antioxidants and vitamins. Thus the present investigation demonstrates that during hyperoxaluric conditions the Spirulina diet must possibly be avoided and can be considered in normal subjects checked for family history of renal stone deposition.


Assuntos
Proteínas de Bactérias/efeitos adversos , Cálculos Renais/etiologia , Rim/metabolismo , Animais , Proteínas de Bactérias/administração & dosagem , Biomarcadores/sangue , Biomarcadores/urina , Nitrogênio da Ureia Sanguínea , Cálcio/urina , Oxalato de Cálcio/urina , Cromatografia Líquida de Alta Pressão , Creatinina/urina , Modelos Animais de Doenças , Radicais Livres/efeitos adversos , Taxa de Filtração Glomerular/fisiologia , Rim/citologia , Rim/patologia , Rim/ultraestrutura , Cálculos Renais/química , Masculino , Microscopia Eletrônica de Varredura , Osteopontina , Distribuição Aleatória , Ratos , Ratos Wistar , Fatores de Risco , Sialoglicoproteínas , Spirulina , Ureia/urina , Ácido Úrico/sangue , Ácido Úrico/urina
4.
Clin Chim Acta ; 348(1-2): 199-205, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15369755

RESUMO

BACKGROUND: C-phycocyanin, a biliprotein pigment found in some blue green algae (Spirulina platensis) with nutritional and medicinal properties, was investigated for its efficacy on sodium oxalate-induced nephrotoxicity in experimentally induced urolithic rats. METHODS: Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg), and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given to one of these groups by 1 h prior to sodium oxalate infusion challenges. The study also encompasses an untreated control group and a phycocyanin-alone treated drug control group. The extent of lipid peroxidation (LPO) was evaluated in terms of renal concentrations of MDA, conjugated diene and hydroperoxides. The following assay was performed in the renal tissue (a) antioxidant enzymes such as superoxide dismutase (SOD) and catalase, (b) glutathione metabolizing enzymes such as glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and glucose 6-phosphate dehydrogenase (G6PD), (c) the low molecular weight antioxidants (GSH, vitamins E and C) and protein carbonyl content. RESULTS: The increased concentrations of MDA, conjugated diene and hydroperoxide (index of the lipid peroxidation) were controlled (P < 0.001) in the phycocyanin-pretreated group. At the outset, the low molecular weight antioxidants were appreciably increased (P < 0.001), whereas the tissue protein carbonyl concentration was decreased (P < 0.001), suggesting that phycocyanin provides protection to renal cell antioxidants. It was noticed that the activities of antioxidant enzymes and glutathione metabolizing enzymes were considerably stabilized in rats pretreated with phycocyanin. CONCLUSION: We suggest that phycocyanin protects the integrity of the renal cell by stabilizing the free radical mediated LPO and protein carbonyl, as well as low molecular weight antioxidants and antioxidant enzymes in renal cells. Thus, the present analysis reveals that the antioxidant nature of C-phycocyanin protects the renal cell against oxalate-induced injury and may be a nephroprotective agent.


Assuntos
Nefropatias/prevenção & controle , Ficocianina/farmacologia , Substâncias Protetoras/farmacologia , Animais , Antioxidantes/metabolismo , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/prevenção & controle , Injeções Intraperitoneais , Rim/citologia , Rim/enzimologia , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxalatos , Ratos , Ratos Wistar
5.
Chem Biol Interact ; 149(1): 1-7, 2004 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15294440

RESUMO

Oxalate induced renal calculi formation and the associated renal injury is thought to be caused by free radical mediated mechanisms. An in vivo model was used to investigate the effect of phycocyanin (from Spirulina platensis), a known antioxidant, against calcium oxalate urolithiasis. Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg) and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given, 1h prior to sodium oxalate infusion. An untreated control and drug control (phycocyanin alone) were also included in the study. We observed that phycocyanin significantly controlled the early biochemical changes in calcium oxalate stone formation. The antiurolithic nature of the drug was evaluated by the assessment of urinary risk factors and light microscopic observation of urinary crystals. Renal tubular damage as divulged by urinary marker enzymes (alkaline phosphatase, acid phosphatase and gamma-glutamyl transferase) and histopathological observations such as decreased tubulointerstitial, tubular dilatation and mononuclear inflammatory cells, indicated that renal damage was minimised in drug-pretreated group. Oxalate levels (P < 0.001) and lipid peroxidation (P < 0.001) in kidney tissue were significantly controlled by drug pretreatment, suggesting the ability of phycocyanin to quench the free radicals, thereby preventing the lipid peroxidation mediated tissue damage and oxalate entry. This accounts for the prevention of CaOx stones. Thus, the present analysis revealed the antioxidant and antiurolithic potential of phycocyanin thereby projecting it as a promising therapeutic agent against renal cell injury associated kidney stone formation.


Assuntos
Antioxidantes/uso terapêutico , Cálculos Renais/prevenção & controle , Rim/patologia , Oxalatos , Ficocianina/uso terapêutico , Fosfatase Ácida/urina , Fosfatase Alcalina/urina , Animais , Proteínas de Bactérias/química , Biomarcadores/urina , Cianobactérias/metabolismo , Modelos Animais de Doenças , Hiperoxalúria/induzido quimicamente , Hiperoxalúria/patologia , Hiperoxalúria/prevenção & controle , Rim/efeitos dos fármacos , Rim/enzimologia , Cálculos Renais/induzido quimicamente , Cálculos Renais/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxalatos/metabolismo , Oxalatos/toxicidade , Ratos , Ratos Wistar , Spirulina , gama-Glutamiltransferase/urina
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