Epimedii Folium is a type of traditional Chinese medicine with effects of nourishing liver and kidney

strengthening the bones and muscles and expelling wind-damp. It is the main component of formulation that could nourish the kidney

strengthen yang and treat impotency

and mainly used for treatment of kidney yang deficiency

rheumatism

osteoporosis and paralysis. Recent studies have shown that icariin is the most abundant flavonoid component in Epimedii and exerts extensive bioactivities of anti-inflammation

anti-oxidant stress

anti-depression and anti-tumor. The molecular pharmacology studies showed that icariin could be used to treat nervous system diseases

osteoporosis

cardiovascular diseases

immune disease and reproductive system diseases by regulating multiple targets and signaling pathways. The protective mechanisms of icariin on skeletal system were extensively studied

involving estrogen receptor α(ERα)-Wnt/beta-catenin

nuclear transcription factor-κB(NF-κB)

cyclic adenosine monophosphate(cAMP) dependent protein kinase(PKA)/cAMP/cAMP response element-binding protein(CREB)

extraeellular-signalregulatedki-nase(ERK)

p38 mitogen-activated protein kinase(MAPK)

RhoA-TAZ

phosphatidylinositol-3-kinases(PI3K)/protein kinase B(Akt)/glycogen synthase kinase 3β(GSK3β)/β-catenin

PI3K/Akt/endothelial nitric oxide synthase(eNOS)/NO/Cyclic guanosinc monophosphate(cGMP)/cGMP protein kinase G(PKG) and other signaling pathways. The significant osteogenesis effects made it a preferred compound in treatment of osteoporosis. However

there was only a few summaries on icariin's mechanisms in regulating the nervous system

protecting the cardiovascular system

regulating the immune system

improving the reproductive function and resisting tumor. In order to accelerate the exploration

discover other molecular mechanisms of icariin

and expand its application prospects

this study reviewed the progress of pharmacological studies on icariin in recent years

and elaborated the effect targets and pertinent pathways

so as to provide the reference for the rational clinical medication and drug research and development.