Curcumin attenuates lupus nephritis upon interaction with regulatory T cells in New Zealand Black/White mice

Abstract

Curcumin has been used in Asian traditional medicine for its medicinal properties. Recent studies have demonstrated that curcumin has antioxidant, anti-tumour and anti-inflammatory activities. The aim of the present study is to investigate the effects of curcumin on established lupus nephritis (LN) in New Zealand Black/White (NZB/W) F1 female mice, in particular, its interaction with regulatory T (T reg ) cells. Starting at 18 weeks of age, mice were fed a standard diet or a diet containing 1 % curcumin until the end of the study. The proteinuria level and the serum levels of IgG1, IgG2a and anti-double-stranded DNA (dsDNA) IgG antibodies were measured. Additionally, IgG immune complex deposition in the glomeruli and renal inflammation were compared between curcumin-treated mice and control mice. Curcumin decreased the proteinuria level and serum levels of IgG1, IgG2a and anti-dsDNA IgG antibodies in NZB/W F1 female mice. IgG immune complex deposition in the glomeruli was reduced in curcumin-treated mice. Furthermore, renal inflammation was also decreased after curcumin treatment. Interestingly, these therapeutic effects of curcumin disappeared after T reg depletion by anti-CD25 antibody injection. Curcumin exerted a protective effect against LN in NZB/W F1 mice. We speculate that the protective effects of curcumin in LN may involve, at least in part, its interaction with T reg cells.

The Use of Functional Chemical-Protein Associations to Identify Multi-Pathway Renoprotectants

“…Numerous renoprotective effects of curcumin have been noted in the literature, such as anti-inflammatory effects, anti-oxidative effects, and anti-apoptosis effects [33]–[42]; it is also known to be involved in HO-1 activity regulation [43]. These findings are in line with our result showing that curcumin is extensively involved in nephropathy-related pathways.…”

Significantly reduced lymphadenopathy, salivary gland infiltrates and proteinuria in MRL-lpr/lprmice treated with ultrasoluble curcumin/turmeric: increased survival with curcumin treatment

“…23 We found delayed onset of proteinuria and urinary cell cast formation (figure 2) in treated mice compared with the lpr-water group. We believe that reduced proteinuria and urinary cell casts observed in the early stages of disease in experimental mice is a direct consequence of inhibition of antigen-antibody interaction by CU.…”

“…Our studies showing significantly increased oxidative damage in lupus patients [19][20][21] led us to investigate an antioxidant/anti-inflammatory agent known as curcumin, [22][23][24][25][26][27][28][29][30][31] obtained from the rhizome of Curcuma longa (turmeric). Curcumin (1,7-bis[4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione), a naturally occurring 'nutraceutical', comprises 4-6% of turmeric.…”

Curcumin protects against fructose-induced podocyte insulin signaling impairment through upregulation of miR-206

“…Curcumin is reported to reduce glomerulosclerosis, improve kidney function in factor‐H‐deficient mice , ameliorate macrophage infiltration in renal glomeruli of streptozotocin‐induced diabetic rats , and decrease proteinuria in New Zealand Black/White mice and glomerulonephritic animals . In our previous study, curcumin and pioglitazone inhibited PTP1B and increased p‐IR and p‐IRS‐1 to enhance Akt and ERK1/2 activation in the liver of fructose‐fed rats .…”