ABSTRACT
Renal injury induced by rheumatoid arthritis is not clear and may be related to the angiotensin II. We aim to investigate the adjuvant-induced arthritis (AIA) injury in rat kidney, focusing the angiotensin II/AT1 pathway. Male Wistar rats were allocated in to three groups: Control, AIA and AIA plus losartan. The AIA was induced by injection of 100 µL of an emulsion of dissected Mycobacterium tuberculosis (50 mg/mL) on the paw. Treatment with losartan was initiated on the first day of immunization (daily subcutaneous injection, 1 mg/kg). After 60 days post immunization, we evaluated kidney function by plasma creatinine, urea and uric acid levels and creatinine depuration; kidney injury by apoptosis analysis and inflammation markers such as macrophages, transforming growth factor beta (TGF-ß) and inducible nitric oxide synthase (iNOS) expression; oxidative stress by plasma thiobarbituric acid reactive substances (TBARS); renal expression of angiotensin receptors subtype 1 (AT1 ) and 2 (AT2 ) and plasma concentration of angiotensin II. AIA rats showed elevated plasma levels of creatinine, urea, uric acid, TBARS and Ang II and reduced creatinine depuration, and enhanced kidney macrophage number, TGF-ß, caspase-3, iNOS and AT1 /AT2 receptors expression. The losartan reduced plasma creatinine and its clearance, reduced macrophages and the expression of TGF-ß and iNOS in renal tissues, and reduced plasma TBARS. We conclude that AIA causes kidney injury by a physiopathological mechanism that involves AT1 stimulation in renal tissue, elevating the presence of macrophages, the expression of TGF-ß and iNOS, as well the local oxidative stress, which contribute to renal function deterioration.
Subject(s)
LosartanABSTRACT
ABSTRACT Introduction: Ischemia and reperfusion (IR) is a process inherent to the procedures involved in the transplantation of organs that causes inflammation, cell death and cell injury, and may lead to rejection of the graft. It is possible that the anti-inflammatory properties of the Brazil nuts (BN) can mitigate the renal injury caused by IR. Objective: To investigate whether the previous intake of BN reduces the expression of markers of inflammation, injury, and cell death after renal IR. Methods: Male Wistar rats were distributed into six groups (N = 6/group): SHAM (control), SHAM treated with 75 or 150 mg of BN, IR, and IR treated with 75 or 150 mg of BN. The IR procedure consisted of right nephrectomy and occlusion of the left renal artery with a non-traumatic vascular clamp for 30 min. BN was given daily from day 1 to 7 before surgery (SHAM or IR), and maintained until sacrifice (48 h after surgery). Inflammation was evaluated by renal expression of COX-2 and TGF-β, injury by the expression of vimentin, and cell death by apoptosis through caspase-3 expression (immunohistochemistry). Results: Pretreatment with 75 mg of BN reduced renal expression of the COX-2, TGF-β, vimentin, and caspase-3. The dose of 150 mg caused increased expression of COX-2. Conclusion: In experimental IR, the damage can be minimized with a prior low-dose intake of BN, improving inflammation, injury, and cell death.
RESUMO Introdução: Isquemia e reperfusão (IR) é um processo inerente aos procedimentos envolvidos no transplante de órgãos, que causa inflamação, morte celular e lesão, podendo levar à rejeição do enxerto. É possível que a castanha-do-brasil (CB), por suas propriedades anti-inflamatórias, possa atenuar a lesão renal causada pela IR. Objetivo: Investigar se a ingestão prévia de CB reduz a expressão de marcadores renais de inflamação, lesão e morte celular após a IR. Métodos: Ratos Wistar machos foram distribuídos em seis grupos (N = 6/grupo): SHAM (controle), SHAM tratado com 75 ou 150 mg de CB, IR, e IR tratado com 75 ou 150 mg de CB. O procedimento de IR consistiu na nefrectomia à direita e oclusão da artéria renal esquerda por 30 minutos. A castanha foi administrada diariamente por sete dias antes da cirurgia (SHAM ou IR), e mantida até o sacrifício (48 horas pós-cirurgia). A inflamação foi avaliada pela expressão renal de COX-2 e TGF-β; a lesão pela expressão de vimentina, e a morte celular por apoptose pela expressão de caspase-3, por imuno-histoquímica. Resultados: O pré-tratamento com 75 mg de CB reduziu a expressão renal de COX-2, de TGF-β, de vimentina e de caspase-3. A dose de 150 mg causou elevação da expressão de COX-2. Conclusão: No modelo experimental de IR renal, os danos podem ser minimizados com a ingestão prévia de baixas doses de CB, melhorando a inflamação, a lesão e a morte celular.
Subject(s)
Animals , Male , Rats , Bertholletia , Acute Kidney Injury/prevention & control , Phytotherapy , Nephritis/prevention & control , Reperfusion Injury/complications , Rats, Wistar , Acute Kidney Injury/etiology , Kidney/blood supply , Nephritis/etiologyABSTRACT
INTRODUCTION: Ischemia and reperfusion (IR) is a process inherent to the procedures involved in the transplantation of organs that causes inflammation, cell death and cell injury, and may lead to rejection of the graft. It is possible that the anti-inflammatory properties of the Brazil nuts (BN) can mitigate the renal injury caused by IR. OBJECTIVE: To investigate whether the previous intake of BN reduces the expression of markers of inflammation, injury, and cell death after renal IR. METHODS: Male Wistar rats were distributed into six groups (N = 6/group): SHAM (control), SHAM treated with 75 or 150 mg of BN, IR, and IR treated with 75 or 150 mg of BN. The IR procedure consisted of right nephrectomy and occlusion of the left renal artery with a non-traumatic vascular clamp for 30 min. BN was given daily from day 1 to 7 before surgery (SHAM or IR), and maintained until sacrifice (48 h after surgery). Inflammation was evaluated by renal expression of COX-2 and TGF-ß, injury by the expression of vimentin, and cell death by apoptosis through caspase-3 expression (immunohistochemistry). RESULTS: Pretreatment with 75 mg of BN reduced renal expression of the COX-2, TGF-ß, vimentin, and caspase-3. The dose of 150 mg caused increased expression of COX-2. CONCLUSION: In experimental IR, the damage can be minimized with a prior low-dose intake of BN, improving inflammation, injury, and cell death.
