Importantly, compared with the diabetic WT mice, the uACR was significantly decreased in the diabetic C5aR1−/− mice (77.14 ± 29.30 vs. 318.50 ± 283.30 μg/mg, p = 0.0369) (Figure 4D), suggesting that the C5aR1 deficiency alleviated proteinuria independent of reducing obesity, hyperglycemia and hyperlipemia in the established DN mice. This evidence concerns the gene C5AR1 and Obesity.