Establishment of modified IgA nephropathy rat model and assessment of oxidative stress

Objective To modify the traditional IgA nephropathy model and evaluate the oxidative stress status of the model, providing experimental evidence for the establishment of IgA nephropathy animal model.Methods Twelve female SPF SD rats weighing 200-240 g were randomly divided into normal control group (group C) and modified model group (group M) according to the random digital table method. The animals in group C were gavaged with normal saline at 4 ml/kg and given subcutaneous injection at 0.4 ml, and those in group M were treated with bovine serum albumin at 600 mg/kg every day by gavage, and subcutaneously injected with carbon tetrachloride at 0.10 ml, castor oil at 0.3 ml, thymosin at 3 mg and LPS at 0.05 mg. At the 12th week, the general states of rats in two groups were observed. Serum creatinine (SCr), blood urea nitrogen (BUN), albumin (Alb) and 24-h urine protein were determined. IgA immunofluorescence, HE staining, biochemical index as well as the state of oxidative stress in the kidney were evaluated.Results All the rats in the group M suffered from mental depression, tiredness, decreased movement and sparse hair. BUN and SCr levels in group M were significantly higher (P<0.05), the level of Alb was significantly lower (P<0.01), and 24-h urine protein was significantly higher than those in group C (P<0.05). In group M, IgA clumps were deposited in the renal mesangial region, the glomerular mesangial area was slightly widened, even moderately broadened, and increased mesangial cells and matrix were observed by HE staining. The levels of SOD and T-AOC in renal tissue of group M were significantly lower (P<0.05), and the level of MDA was significantly higher than that of group C (P<0.05).Conclusions The modified IgA nephropathy rat model is optimal, and the biochemical and pathological indexes are similar to those of human IgA nephropathy. The change of oxidative stress in the kidney is one of the important pathological mechanisms involved in the process.