Immunomodulatory effect from ethanol extract and ethyl acetate fraction of Curcuma heyneana Valeton and Zijp: Transient receptor vanilloid protein approach

This study aims to discover the immunomodulatory potential of the ethanol extract (EE) and the ethyl acetate fraction (EAF) of Curcuma heyneana Valeton and Zijp (Indonesian name: temu giring) rhizome using mice models. The affinity of the curcuminoid (curcumin, dimethoxy-, and bisdemethoxy-) through the Transient Receptor Potential Vanilloid 1 (TRPV1) was determined using Mollegro molecular docking in silico. The curcuminoid concentration of the EE and EAF of C. heyneana rhizome were determined using thin-layer chromatography densitometry. In vivo studies in mice models were conducted using the carbon clearance method to determine the phagocytosis index, and the number of leukocytes in the blood and spleen. Forty mice were divided into eight groups, including negative control (given 1% CMC-Na), positive control (given Stimuno Forte® suspension at a dose of 6.5 mg/kg BW), three groups given the EAF of C. heyneana rhizome extract at a dose of 125 mg/kg BW, 250 mg/kg BW, and 500 mg/kg BW, respectively, and three groups were given EE of temu giring rhizome extract with doses of 125 mg/kg BW, 250 mg/kg BW, and 500 mg/kg BW, respectively. E.E. and E.A.F. of C. heyneana (temu giring) rhizome extract contained dimethoxy curcumin (0.176 ± 0.01 and 4.53 ± 0.02 %b/b) greater than another curcuminoid, bisdemetoxy curcumin and curcumin. EE at 125 mg/kg BW and EAF dose at 500 mg/kg B W. of temu giring rhizome have immunostimulant activity with a phagocytosis index value of >1 compared to the negative control (p < 0.05). Additionally, both increase the number of lymphocytes, monocytes, and neutrophil cells in peripheral blood and spleen compared to the negative control (p < 0.05). Their activity was seen as similar to the positive control. Therefore, the EE of C. heyneana rhizome has immunostimulant activity, and the EAF of C. heyneana rhizome has immunosuppressant activity at 125 mg/kg BW and immunostimulant at a higher dose. The activity of temu giring as an immunomodulator was associataed with its affinity to TRPV1.