Long-Term Electroacupuncture Stimulation Prevents Osteoporosis in Ovariectomised Osteopaenic Rats through Multiple Signalling Pathways

Abstract

Background

The pathogenic mechanisms of postmenopausal osteoporosis (PMOP) development are complex and are related to multiple cellular signalling transduction pathways. The aim of this study was to compare the effects of electroacupuncture (EA) at GV4/GV6 versus BL20/BL23 on the bones in ovariectomised (OVX) rats to explore the pathways that mediate the effects of EA on bone.

Methods

Forty female Sprague-Dawley rats were allocated to one of four groups (n=10 rats each) that received sham surgery (Sham group), OVX surgery only (OVX group), OVX surgery plus EA at GV4/GV6 (GV group) and OVX surgery plus EA at BL20/BL23 (BL group). Bone turnover markers osteocalcin (OC) and tartrate-resistant acid phosphatase 5b (TRACP 5b) were measured in serum, and bone mineral density (BMD) of the lumbar vertebrae and histomorphology of the femur were evaluated. Moreover, the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) was detected by ELISA. The expression of lipoprotein receptor-related protein (LRP) 5, β-catenin, runt-related transcription factor (Runx) 2 involving Wnt/β-catenin signalling and p38, c-Jun N-terminal kinase (JNK) and extracellular regulated protein kinases 1/2 involving mitogen-activated protein kinase signalling were determined by Western blotting.

Results

The two EA-treated groups demonstrated increased levels of OC and the BMD of lumbar vertebrae, decreased levels of TRACP 5b and improved bone microstructure in the femur, compared with the untreated OVX group (P<0.05). Histomorphology analysis showed that EA treatment significantly increased the values of the trabeculae (µm), trabecular area (%) and trabecular bone number (per mm) and reduced trabecular separation (mm), compared with the OVX group. In addition, the ratio of OPG to RANKL and LRP5, β-catenin and Runx2 expression were significantly upregulated, while the expression of phosphorylated (p)-p38 and p-JNK were downregulated in EA-treated groups compared with the OVX group.

Conclusion

EA attenuates PMOP and it appears that the mechanism involves the regulation of multiple targets and pathways.

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References

National Institutes of Health. Osteoporosis prevention, diagnosis, and therapy. JAMA 2001; 285: 785–95.

Kanis

J.A.

Diagnosis of osteoporosis and assessment of fracture risk. The Lancet 2002; 359: 1929–36.

Meczekalski

, Czyzyk

, Blazej

, Adam

[Selective estrogen receptor modulators in treatment of postmenopausal osteoporosis]. Ginekol Pol 2009; 80: 213–7.

Cole

, Dennison

, Cooper

Update on the treatment of post-menopausal osteoporosis. Br Med Bull 2008; 86: 129–43.

Nelson

H.D.

Menopause. Lancet 2008; 37: 760–70.

Rossouw

J.E.

, Anderson

G.L.

, Prentice

R.L.

Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial. JAMA 2002; 288: 321–3.

Fung

P.C.

Probing the mystery of Chinese medicine meridian channels with special emphasis on the connective tissue interstitial fluid system, mechanotransduction, cells durotaxis and mast cell degranulation. Chin Med 2009; 4: 10.

Han

J.S.

Acupuncture: neuropeptide release produced by electrical stimulation of different frequencies. Trends Neurosci 2003; 26: 17–22.

Mason

, Tovey

, Long

A.F.

Evaluating complementary medicine: methodological challenges of randomised controlled trials. BMJ 2002; 325: 832–4.

10.

Sunay

, Ozdiken

, Arslan

The effect of acupuncture on postmenopausal symptoms and reproductive hormones: a sham controlled clinical trial. Acupunct Med 2011; 29: 27–31.

11.

Zhou

, Wang

, Pan

Clinical observation on combined acupuncture and medication for osteoporosis in postmenopausal women. J Acupunct Tuina Sci 2011; 9: 370–5.

12.

, Yang

, Qing

Effects of electroacupuncture on bone mineral density, oestradiol level and osteoprotegerin ligand expression in ovariectomised rabbits. Acupunct Med 2014; 32: 37–42.

13.

Feng

, Lin

, Zhang

Electroacupuncture promotes insulin-like growth factors system in ovariectomized osteoporosis rats. Am J Chin Med 2008; 36: 889–97.

14.

Wei

Y.F.

, Liu

Y.L.

, Zhang

S.H.

Effect of electroacupuncture on plasma estrin and bone mineral density in ovariectomized rats. Zhen Ci Yan Jiu 2007; 32: 38–41.

15.

Wang

, Jin

, Higgins

The current view for the silencing of the spindle assembly checkpoint. Cell Cycle 2014; 13: 1694–701.

16.

Lin

, Chen

, Wei

Ursolic acid inhibits colorectal cancer angiogenesis through suppression of multiple signaling pathways. Int J Oncol 2013; 43: 1666–74.

17.

S.X.

, Tian

H.M.

, Yan

Changes of multiple protein phosphorylation signal transduction pathways in the process of repairing rat gastric mucosa through stimulation of stomach meridian with electro-acupuncture. J Clinical Rehabilitative Tissue Engineering Res 2009; 13: 8075–9.

18.

Zheng

, Wu

, Nie

Electroacupuncture at the governor vessel and bladder meridian acupoints improves postmenopausal osteoporosis through osteoprotegerin/RANKL/RANK and Wnt/β-catenin signaling pathways. Exp Ther Med 2015; 10: 541–8.

19.

Mak

J.C.

Acupuncture in osteoporosis: more evidence is needed. Acupunct Med 2015; 33: 440–1.

20.

Lin

J.G.

, Chen

W.L.

Acupuncture analgesia: a review of its mechanisms of actions. Am J Chin Med 2008; 36: 635–45.

21.

Liao

, Li

Electroacupuncture protects against articular cartilage erosion by inhibiting mitogen-activated protein kinases in a rat model of osteoarthritis. Acupunct Med 2016; 34: 290–5.

22.

Zhang

Y.M.

, Dai

Q.F.

, Chen

W.H.

Effects of acupuncture on cortical expression of Wnt3a, β-catenin and Sox2 in a rat model of traumatic brain injury. Acupunct Med 2016; 34: 48–54.

23.

, Liu

B.X.

, Haung

C.J.

The progress of acupuncture treatment on postmenopausal osteoporosis. J Zhejiang Univ Tradit Chin Med 2011; 2: 301–11.

24.

Frolik

C.A.

, Bryant

H.U.

, Black

E.C.

Time-dependent changes in biochemical bone markers and serum cholesterol in ovariectomized rats: effects of raloxifene HCl, tamoxifen, estrogen, and alendronate. Bone 1996; 18: 621–7.

25.

Sato

, Bryant

H.U.

, Iversen

Advantages of raloxifene over alendronate or estrogen on nonreproductive and reproductive tissues in the long-term dosing of ovariectomized rats. J Pharmacol Exp Ther 1996; 279: 298–305.

26.

Wang

H.D.

, Chen

, Inoue

Effects of electroacupuncture at GB points on markers of osteoporosis and bodyweight in ovariectomised rats. Acupunct Med 2015; 33: 465–71.

27.

Hartmann

A Wnt canon orchestrating osteoblastogenesis. Trends Cell Biol 2006; 16: 151–8.

28.

Kong

Y.Y.

, Yoshida

, Sarosi

OPGL is a key regulator of osteoclastogenesis, lymphocyte development and lymph-node organogenesis. Nature 1999; 397: 315–23.

29.

Hofbauer

L.C.

, Schoppet

Clinical implications of the osteoprotegerin/RANKL/RANK system for bone and vascular diseases. JAMA 2004; 292: 490–5.

30.

Kim

, Kim

, Jho

E.H.

Wnt/β-catenin signalling: from plasma membrane to nucleus. Biochem J 2013; 450: 9–21.

31.

Bodine

P.V.

, Komm

B.S.

Wnt signaling and osteoblastogenesis. Rev Endocr Metab Disord 2006; 7: 33–9.

32.

, Li

, Liu

Bauhinia championi (Benth.) Benth. polysaccharides upregulate Wnt/β-catenin signaling in chondrocytes. Int J Mol Med 2013; 32: 1329–36.

33.

Roux

P.P.

, Blenis

ERK and p38 MAPK-activated protein kinases: a family of protein kinases with diverse biological functions. Microbiol Mol Biol Rev 2004; 68: 320–44.

34.

Cargnello

, Roux

P.P.

Activation and function of the MAPKs and their substrates, the MAPK-activated protein kinases. Microbiol Mol Biol Rev 2011; 75: 50–83.

35.

Matsumoto

, Sudo

, Saito

Involvement of p38 mitogen-activated protein kinase signaling pathway in osteoclastogenesis mediated by receptor activator of NF-kappa B ligand (RANKL). J Biol Chem 2000; 275: 31155–61.

36.

Ikeda

, Nishimura

, Matsubara

Critical roles of c-Jun signaling in regulation of NFAT family and RANKL-regulated osteoclast differentiation. J Clin Invest 2004; 114: 475–84.

37.

Monje

, Hernández-Losa

, Lyons

R.J.

Regulation of the transcriptional activity of c-Fos by ERK A novel role for the prolyl isomerase PIN1. J Biol Chem 2005; 280: 35081–4.

38.

Ang

, Liu

, Qi

Mangiferin attenuates osteoclastogenesis, bone resorption, and RANKL-induced activation of NF-κB and ERK. J Cell Biochem 2011; 112: 89–97.