The Effect of Dietary Fiber Intake on Systemic Lupus Erythematosus (SLE) Disease in NZB/W Lupus Mice

Dysbiosis in the gut microbiota has been observed in a various autoimmune disease, including SLE, which could cause a leaky gut, triggering an immune response, and thus worsening autoimmune disease expression. In our current studies, we hypothesized that increasing dietary fiber would create a healthy microbiota environment in the gut, leading to decreased leakiness of the gut and to decreased disease expression in and NZB/NZW female mice. NZB/NZW mice were placed on standardized high fiber (HF 30%) or low fiber (LF 0.4%) for 12 weeks beginning at 10 weeks of age. Mice were assessed as they aged for various parameters of disease including proteinuria and anti-dsDNA antibody production. Alteration of the microbiota and short chain fatty acid levels were also assessed. At 36 weeks-of-age, the mice were euthanized and we assessed occlusion protein expression, splenocyte profiles, and kidney tissue. We found as the mice aged, their body weights, anti-dsDNA antibody levels, and proteinuria were not significantly different between the groups. Similarly, there were no differences in SCFA levels. In regard to the microbiota, Chlostridiales bacteria were consistently increased in the HF treated mice compared to the LF treated mice. In regard to disease progression, spleen weight, immune cell profiles, proteinuria, dsDNA levels, and kidney pathology, there was no difference between the HF and LF treated groups. Taken together, these results indicate that in the NZB/W female mouse, a HF diet may alter the microbiota but does not influence disease progression.