Aim: To investigate the protective effects of rhein lysinate (RHL), a major bioactive constituent of the rhizome of rhubarb (Rheum palmatum Linn or Rheum tanguticum Maxim), against kidney impairment in senescence-prone inbred strain 10 (SAMP10) mice. mice with RHL significantly reduced the MAD level, and increased the SOD and GSH-px levels in the kidneys. Glomerulonephritis was observed in SAMP10 mice but not in SAMR1 mice. RHL decreased the incidence of glomerulonephritis, and significantly decreased the levels of TNF-, IL-6, NF-B, collagen types I and Tyrphostin AG-1478 III in the kidneys. Conclusion: Accelerated senescence is usually associated with glomerulonephritis in SAMP10 mice, and RHL prolongs their median survival time by reducing the severity of glomerulonephritis. or throughout the study. The mice were divided into four groups: the SAMR1 control group (for 15 min at 4 C. The antioxidant enzyme activities (including the activities of SOD and GSH-px) and the MDA content in the obtained supernatant was measured using assay packages, according to the manufacturer’s instructions. Histology and immunohistochemistry For histological analysis, kidney tissues fixed with 4% buffered paraformaldehyde were embedded in paraffin, and 3-m-thick sections were prepared. The sections were then stained with hematoxylin-eosin. Immunohistochemical analyses were performed using antibodies against TNF- and IL-6. The sections were deparaffinized and quenched in 3% H2O2 for 15 min to block endogenous peroxidase and then washed in PBS. The sections were subsequently incubated with anti-TNF- Rabbit polyclonal to ARHGAP20. or anti-IL-6 antibodies for 2 h, followed by incubation with a biotinylated secondary antibody and ABC reagent (Biomed Organization, Beijing, China), as recommended by the vendor. The color was developed by incubating the sections with diaminobenzidine as a substrate. The slides were counterstained with Mayer’s hematoxylin, and slides that were preincubated with BSA served as negative controls. Western blotting Western blots were employed to detect the levels of TNF, IL-6, NF-B, COL1A1, COL3A1, and COL4A2, as well as the phosphorylation of NF-B in the kidneys. Briefly, the kidney tissues were treated with a lysis buffer and a cocktail of phosphatase inhibitors (Roche, Indianapolis, IN, USA). Samples (30 g) were fractionated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After the proteins were transferred to a PVDF membrane, the membrane was incubated in a blocking buffer made up of BSA (1%) and Tween 20 (0.1%, or Rheum tanguticum Maxim). In previous Tyrphostin AG-1478 studies, rhein was found to exhibit a variety of bioactivities, such as inhibiting IL-1-induced chondrocyte activation14, decreasing the cellular hypertrophy of mesangial cells15, suppressing tumor cell proliferation, and inducing tumor cell apoptosis16. In addition, rhein exhibits synergy with mitomycin17. In our previous study, we also decided that RHL inhibited malignancy cell proliferation, but the effect of RHL on glomerulonephritis was unclear. In the present study, we found that RHL administered in drinking water increased the median survival time of SAMP10 mice and improved their kidney function, as revealed by decreased creatinine and urea levels (Table 1). Moreover, we concluded that RHL decreased the occurrence of uremia by reducing the severity of glomerulonephritis in SAMP10 mice, and this discovery motivated us to elucidate the mechanism. Oxidative stress Tyrphostin AG-1478 plays an important role in kidney injury during aging. The MDA, SOD, and GSH-px levels are indicators of the oxidative stress status. Our results indicate that RHL decreases the level of MDA and increases the levels of SOD and GSH-px in kidney tissues. Thus, it can be deduced that RHL protects the kidney by reducing the level of reactive oxygen species. The progression of IgA nephropathy (IgAN), the most frequent type of main glomerulonephritis, is associated with high levels of mononuclear leukocyte infiltration into the kidneys. These cells primarily consist of T cells and macrophages18. In this study, compared with SAMR1 mice, the SAMP10 control mice displayed kidney disease associated with the invasion of mononuclear macrophages, atrophy and kidney destruction. This disease might be related to inflammation due to autoimmune reactions. In addition, one of the characteristics of aging is usually deposition of lipofuscin in the tissue. In the present study, we observed that RHL guarded the kidney and delayed senescence in the mice by preventing the development of mouse autoimmune glomerulonephritis through potent immune-modulating.