Identification of Novel Standard Compounds for Standardization of Sinbaro3 Pharmacopuncture

The Anti-Inflammatory Effects of Shinbaro3 Is Mediated by Downregulation of the TLR4 Signalling Pathway in LPS-Stimulated RAW 264.7 Macrophages

Shinbaro3, a formulation derived from the hydrolysed roots of Harpagophytum procumbens var. sublobatum (Engl.) Stapf, has been clinically used in the pharamacopuncture treatment of arthritis in Korea. In the present study, Shinbaro3 inhibited NO generation in LPS-induced RAW 264.7 cells in a dose-dependent manner. Shinbaro3 also downregulated the mRNA and protein expression of inflammatory mediators in a dose-dependent manner. Three mechanisms explaining the effects of Shinbaro3 in RAW 264.7 cells were identified as follows: (1) inhibition of the extracellular signal-regulated kinase 1 and 2 (ERK1/2), stress-activated protein kinase (SAPK)/c-Jun N-terminal protein kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) pathways; (2) suppression of IκB kinase-α/β (IKK-α/β) phosphorylation and nuclear factor-kappa B (NF-κB) subunits in the NF-κB pathway, which are involved in MyD88-dependent signalling; and (3) downregulation of IFN-β mRNA expression via inhibition of interferon regulatory factor 3 (IRF3) and Janus-activated kinase 1 (JAK1)/signal transducer and activator of transcription 1 (STAT1) phosphorylation, which is involved in TRIF-dependent signalling. Shinbaro3 exerted anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophage cells through modulation of the TLR4/MyD88 pathways, suggesting that Shinbaro3 is a novel anti-inflammatory therapeutic candidate in the field of pharmacopuncture.

Anti-osteoporotic activity of harpagide by regulation of bone formation in osteoblast cell culture and ovariectomy-induced bone loss mouse models

ETHNOPHARMACOLOGICAL RELEVANCE

Harpagide, an iridoid glucoside, is a constituent of the root of Harpagophytum procumbens var. sublobatum (Engl.) Stapf, Devil's claw which has been used in patients with osteoarthritis (OA). In the present study, we investigated the anti-osteoporotic potential of harpagide and its underlying mechanism of action in in vitro cell culture and in vivo bone loss animal models.

MATERIAL AND METHODS

Harpagide was obtained from the alkalic hydrolysis of harpagoside, a major constituent of H. procumbens var. sublobatum Analysis of biomarkers for bone formation in osteoblastic MC3T3-E1 cells and bone resorption in osteoclast cells derived from mouse bone marrow cells was performed to evaluate the mechanism of action. The protective activity of harpagide against bone loss was also evaluated in ovariectomized (OVX) mouse model.

RESULTS

Harpagide improved bone properties by stimulating the process of differentiation and maturation of osteoblast cells and suppressing the process of RANKL-induced differentiation of osteoclast cells. In OVX-induced bone loss mouse model, oral administration of harpagide significantly improved recovery of bone mineral density, trabecular bone volume, and trabecular number in the femur. Harpagide also prevented increase of trabecular separation and structure model index induced by OVX. Harpagide effectively inhibited the serum levels of biochemical markers of bone loss, including alkaline phosphatase, osteocalcin, C-terminal telopeptide, and tartrate-resistant acid phosphatase.

CONCLUSION

Taken together, the present study demonstrates that harpagide has a potential for prevention of bone loss in OVX mice by regulating the stimulation of osteoblast differentiation and the suppression of osteoclast formation. Therefore, these findings suggest that harpagide might serve as a bioactive compound derived from H. procumbens var. sublobatum for improvement of age-dependent bone destruction disease.