Fructus Ligustri Lucidi (Zhen Zi) has been traditionally used for treating bone disorders and for the treatment of age-related symptoms. According to Wang Ang , Fructus Ligustri Lucidi coupled with Herba Ecliptae can “Supplement the lower back and knees, strengthen the sinews and bones, strengthen the kidneys, and blacken hair”. Fructus ligustri has lately even been added to testosterone boosters.
Fructus Ligustri Lucidi may Prevent Bone Loss
Fructus ligustri lucidi extract has been reported to exert osteoprotective effect by improving bone turnover and calcium balance in both young  and aging  animals as well as postmenopausal women . FLL extract has also prevented bone marrow loss in patients receiving chemoterapy . Chun Hay Ko et al.  reported that aqueous extract of FLL significantly reduced lumbar spine bone mineral density loss in a dose-dependent manner without cytotoxic effects. Fructus ligustri lucidi extract can directly regulate vitamin D metabolism via increased renal 1-OHase and vitamin D receptor protein expression and activity [4,6], which further enhances calcium balance via increased vitamin D-dependent calcium transport . This may in part explain reduced urinary and fecal calcium excretion .
Fructus ligustri lucidi extract seems to be an ideal oral agent for treatment and prevention (as alternative medicine) of postmenopausal osteoporosis.
Can Fructus Ligustri Improve Exercise Capacity (or Increase Testosterone)?
Shiyuan and associates  reported that 6 weeks of Fructus ligustri extract in combination with exhaustive exercise significantly increased antioxidant enzyme action in the kidneys of animal models and increased time to fatigue by 23.09%. Authors of this study concluded that FLL extract plays an important role in improving exercise capacity and delaying time to fatigue (in animals) . Glutathione (GSH) content in kidneys was also significantly higher in FLL extract supplemented animals . Extend the time to fatigue in animal models was also shown in another study which also reported increased NOS activity and NO production . Nourishing effects of FLL on the liver and kidneys was also reported by Feng and colleagues . The main finding in Feng et al. study  was the possible protective effect of ligustrum fruit on spermatogenesis and blood gonadal hormones in diabetic rats. The serum luteinizing hormone, follicle-stimulating hormone and testosterone levels were higher in FLL supplemented rats but failed to reach statistical significance .
Fructus ligustri lucidi (30 g/kg) was also reported to significantly decreased blood glucose level in normal mice after 10 days .
Side Effects and Toxicity
Unlike other osteoprotective agents, Fructus ligustri lucidi seems to be well tolerated and has no reported adverse effects. Chun Hay Ko et al.  reported no cytotoxic effects at either low or high dose.
Li, Ze-Yun, et al. “LC-MS determination and pharmacokinetic study of salidroside in rat plasma after oral administration of suspensions of traditional Chinese medicine Erzhi Wan and Fructus Ligustri lucidi.” Journal of Pharmaceutical Analysis 1.1 (2011): 8-12.
- Zhang, Yan, et al. “Effects of Fructus Ligustri Lucidi extract on bone turnover and calcium balance in ovariectomized rats.” Biological and Pharmaceutical Bulletin 29.2 (2006): 291-296.
Ko, Chun Hay, et al. “Osteoprotective effects of Fructus Ligustri Lucidi aqueous extract in aged ovariectomized rats.” Chin Med 5 (2010): 39.
Zhang, Yan, Mansau Wong, and Chunfu Wu. “Anti-osteoporotic effects of medicinal herbs and their mechanisms of action.” Asian Journal of Traditional Medicines 1 (2006): 3-4.
Dong, Xiao-Li, et al. “Ethanol extract of Fructus Ligustri Lucidi increases circulating 1, 25-dihydroxyvitamin D3 by inducing renal 25-hydroxyvitamin D-1α hydroxylase activity.” Menopause 17.6 (2010): 1174-1181.
Zhang, Yan, et al. “Fructus ligustri lucidi extract improves calcium balance and modulates the calciotropic hormone level and vitamin D-dependent gene expression in aged ovariectomized rats.” Menopause 15.3 (2008): 558-565.
Shiyuan, Qi, and Xiong Zhengying. “An Experimental Research on Effects of Fructus Ligustri Lucidi Extracts on Kidney Tissue and Exercise Capacity in Rats.” Journal of Ningxia University (Natural Science Edition) 1 (2013): 016.
Yun-hui, M. A. “Effect of Ligustrum Lucidum Extract on NO Content and Total NOS Activity in Different Tissues of Rats [J].” Journal of Beijing Sport University 6 (2011): 016.
Feng, Shi-Liang, et al. “Effect of ligustrum fruit extract on reproduction in experimental diabetic rats.” Asian journal of andrology 3.1 (2001): 71-73.
- Zhiqi, Hao, Hang Bingqian, and Wang Ying. “Hypoglycemic Effect of Fructus Ligustri Lucidi.” China Journal of Chinese Materia Medica 7 (1992): 022.