Curcumin Attenuates Both Acute and Chronic Immune Nephritis.

Curcumin is known to have immunomodulatory potential in addition to anti-oxidant, anti-inflammatory and anti-carcinogenic effects. The aim of the present study is to investigate the therapeutic effects of curcumin on immune-mediated renal disease in an anti-glomerular basement membrane (GBM) model (representing acute kidney Injury, AKI) and murine lupus model (representing chronic kidney disease, CKD). In the AKI model, female anti-GBM 129/svj mice were administered with curcumin right before disease induction. In the CKD model, female MRL.lpr mice at the age of 8-10 weeks old were treated with curcumin or placebo via oral gavage daily for two months. After treatment, serum autoantibody levels, splenomegaly and spleen cellularity were reduced in murine lupus. Collectively, curcumin ameliorated kidney disease in the two mouse models with either acute or chronic nephritis, as marked by reduced proteinuria, blood urea nitrogen, glomerulonephritis, crescent formation, tubule-interstitial disease, and renal infiltration by lymphocytes. In addition, curcumin treatment reduced activation of the NFkB, MAPK, AKT and pBAD pathways either systemically, or within the inflamed kidneys. These findings suggest that natural food supplements could become an alternative approach to ameliorating immune-mediated kidney diseases.

Prevention of murine lupus nephritis by targeting multiple signaling axes and oxidative stress using a synthetic triterpenoid.

OBJECTIVE: Current treatment options for lupus are far from optimal. Previously, we reported that phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin, MEK-1/ERK-1,2, p38, STAT-3, STAT-5, NF-κB, multiple Bcl-2 family members, and various cell cycle molecules were overexpressed in splenic B cells in an age-dependent and gene dose-dependent manner in mouse strains with spontaneous lupus. Since the synthetic triterpenoid methyl-2-cyano-3,12-dioxooleana-1,9-dien-28-oate (CDDO-Me) has been shown to inhibit AKT, MEK-1/2, and NF-κB, and to induce caspase-mediated apoptosis, we tested the therapeutic potential of this agent in murine lupus nephritis. METHODS: The synthetic triterpenoid CDDO-Me or placebo was administered to 2-month-old B6.Sle1.Sle3 mice or MRL/lpr mice, which develop spontaneous lupus. All mice were phenotyped for disease. RESULTS: CDDO-Me-treated mice exhibited significantly reduced splenic cellularity, with decreased numbers of both CD4+ T cells and activated CD69+/CD4+ T cells compared to the placebo-treated mice. These mice also exhibited a significant reduction in serum autoantibody levels, including anti-double-stranded DNA (anti-dsDNA) and antiglomerular antibodies. Finally, CDDO-Me treatment attenuated renal disease in mice, as indicated by reduced 24-hour proteinuria, blood urea nitrogen, and glomerulonephritis. At the mechanistic level, CDDO-Me treatment dampened MEK-1/2, ERK, and STAT-3 signaling within lymphocytes and oxidative stress. Importantly, the NF-E2-related factor 2 pathway was activated after CDDO-Me treatment, indicating that CDDO-Me may modulate renal damage in lupus via the inhibition of oxidative stress. CONCLUSION: These findings underscore the importance of AKT/MEK-1/2/NF-κB signaling in engendering murine lupus. Our findings indicate that the blockade of multiple signaling nodes and oxidative stress may effectively prevent and reverse the hematologic, autoimmune, and pathologic manifestations of lupus.

Peritoneal catheter implantation elicits IL-10-producing immune-suppressor macrophages through a MyD88-dependent pathway.

Catheters are implanted into the peritoneal cavity during the process of peritoneal dialysis. Though these catheters may be effective and beneficial, the impact of catheters on the immune system is poorly understood. Catheters and other devices implanted in the peritoneal cavity elicit a foreign body reaction. However, the immunological consequences of this remain uncharacterized. To model this, catheters were implanted into the peritoneal cavity of healthy mice. Catheter implantation induced rapid cellular changes within the peritoneal cavity. Whereas B-cells and T-cells were reduced, catheter implantation was associated with the rapid expansion of F4/80-low-positive, CD11b-positive macrophages that elaborated IL-10, and suppressed T-cell division and Th1 skewing in co-culture assays. Peritoneal catheter elicited macrophages had increased Jmjd3 but reduced NF-κB activation, and their emergence was MyD88-dependent. Collectively, these studies indicate that foreign body implantation into the peritoneal cavity is associated with the expansion of suppressor macrophages. Whether peritoneal cavity catheter implantation may have systemic immunoregulatory roles remains to be explored.