Table 2.
Some recent findings on the effect of Curcumin on the immune system.
| Bioassay | Dose | Remark | References |
|---|---|---|---|
| ELISA assay | 100–200 mg/kg diet | Significant increase in estradiol, follicle-stimulating hormone levels, IgA, IgG, luteinizing hormone, and complement C3 activity in the serum (P < 0.05). | (99) |
| Flow cytometry | - | Curcumin suppressed inflammatory monocytes across the blood-brain barrier (BBB) in Experimental Autoimmune Encephalomyelitis (EAE) mice, suppressed the spread of microglia, and limited infiltration of other effector immune cells, resulting in a reduction in EAE morbidity from 100 to 30%. It was due to the immunomodulatory impact of curcumin-loaded high-density lipoprotein-mimicking peptide-phospholipid scaffold (Cur-HPPS) on inflammatory monocytes, which inhibited the activation of NF-κB and decreased the expression of adhesion-and migration-related molecules. | (88) |
| Serum biochemical parameters assay | 196.11–788.52 mg/kg diet | Curcumin up-regulated the mRNA levels of LYZ, C3, and antimicrobial peptides [hepcidin, liver-expressed antimicrobial peptide-2 (LEAP-2), β-defensin]; anti-inflammatory cytokines of interleukin-10 (IL-10); an inhibitor of κBα (IκBα); and transforming growth factor β1 (TGF-β1); whereas, down-regulated pro-inflammatory cytokines of tumor necrosis factor-α (TNF-α), IL-6, IL-8, and IL-1β; IκB kinases (IKKα, IKKβ, and IKKγ) and nuclear factor kappa B p65 (NF-κB p65) mRNA levels in the liver and blood. | (89) |
| Serum biochemistry assay | 100–200 mg/kg diet | A substantial reduction in total leukocytes as a result of the reduction in lymphocytes was observed in animals receiving curcumin and was observed for total serum protein and globulin levels. | (75) |
| Serum inflammatory cytokines analysis | 100-300 mg/kg diet | The curcumin treatment group had reduced inflammatory responses (TNF-α, IL-1β, and IL-6,) as compared to the control group. | (92) |
| Western blot analysis | 100–300 mg/kg diet | TLR4, PCNA, and its downstream gene expression, as well as protein expression (NFκB, TLR4, and PCNA), were significantly downregulated in the heat stress curcumin supplemented group as compared to the control group. | (92) |
| ELISA assay | 200 μg/mouse | Curcumin suppressed the development of antigen-specific IgE and IgG1, inhibited CD4+ T function, and decreased ovalbumin-sensitized B-cell memory. | (100) |
| Immunofluorescence assay | - | Expression of p-STAT3Y705 and PD-L1 was similarly decreased in vivo. | (101) |
| Flow cytometry | - | After curcumin treatment, the anti-tumor immune response was remarkably improved by rising CD8 positive T cells and decreasing Tregs and MDSCs. | (101) |
| Hemagglutination assay | 5–10 mg/kg diet | Curcumin nanoparticle significantly induced primary humoral immune response with 9.00 ± 1.00 antibody titer (P < 0.05), free curcumin suppressed immunity with 3.33 ± 0.67 antibody titer compared to control. Similar findings were found with secondary humoral antibody titers. | (102) |
| Intracellular staining | 10,000 mg/kg diet | Curcumin diet reduced all populations of Th1/Th2/Th17 cells and attenuated various symptoms such as splenomegaly in scurf mice. | (91) |
| Cytokine measurement assay | 10,000 mg/kg diet | In vitro studies showed that curcumin treatment directly decreased the development of Th1/Th2 /Th17 cytokines in CD4 + T cells from IL-4, IL-17A, and IFN-γ. | (91) |
| Oxidative stress and immunological assay | 50–200 mg/kg diet | Total IgM and IgG levels increased significantly, in particular. | (85) |