**Xiao-chen Gao 1, Jing-wei Lv 1, Chun-nan Li 1, Nan-xi Zhang 1, Lin-lin Tian 1, Xi-ying Han 2, Hui Zhang 1,\* and Jia-ming Sun 1,\***


Received: 9 May 2019; Accepted: 30 May 2019; Published: 3 June 2019

**Abstract:** *Lepidium meyenii* is now widely consumed as a functional food and medicinal product, which is known as an enhancer of reproductive health. However, the specific chemical composition and mechanism of action for improving sexual function are unclear. The present study aims at screening and determining the potential compounds, which promote mouse leydig cells (TM3) proliferation. The partial least squares analysis (PLS) was employed to reveal the correlation between common peaks of high performance liquid chromatography (HPLC) fingerprint of *L. meyenii* and the proliferation activity of TM3. The results suggested that three compounds had good activities on the proliferation of TM3 and promoting testosterone secretion, there were *N*-benzyl-hexadecanamide, *N*-benzyl-(9z,12z)-octadecadienamide and *N*-benzyl-(9z,12z,15z)-octadecatrienamide which might be the potential bioactive markers related to the enhancing sexual ability functions of *L. meyenii*. The first step in testosterone synthesis is the transport of cholesterol into the mitochondria, and the homeostasis of mitochondrial function is related to cyclophilin D (CypD). In order to expound how bioactive ingredients lead to promoting testosterone secretion, a molecular docking simulation was used for further illustration in the active sites and binding degree of the ligands on CypD. The results indicated there was a positive correlation between the binding energy absolute value and testosterone secretion activity. In addition, in this study it also provided the reference for a simple, quick method to screen the promoting leydig cell proliferation active components in traditional Chinese medicine (TCM).

**Keywords:** *Lepidium meyenii*; high-performance liquid chromatography-electrospray ionization/mass spectrometry; partial least squares; ultrafiltration affinity; molecular docking
