Siberian Ginseng

In vitro studies indicate that eleuthero contains chemicals that bind to estrogen, progestin, mineralocorticoid, and glucocorticoid receptors ⁽¹⁰⁾. In macrophages, a Siberian ginseng extract suppressed LPS-induced iNOS expression and thus nitric oxide production by possibly inhibiting nuclear factor-kappa B activity ^{(15) (16)} or Akt and JNK signaling ⁽¹⁶⁾, and inhibited reactive oxygen species production ⁽¹⁷⁾. Siberian ginseng extract also moderately inhibited breast cancer resistance protein (BCRP)-mediated methotrexate transport in BCRP-expressing membrane vesicles ⁽²¹⁾. Eleutheroside B, eleutheroside E, and isofraxidin — active constituents of Siberian ginseng — showed protective effects against Aβ(25-35)-induced atrophies of axons and dendrites in rat cultured cortical neurons ⁽²²⁾. Isofraxidin also inhibited cell invasion and the expression of matrix metalloproteinase-7 by human hepatoma cell lines HuH-7 and Hep G-2, possibly through the inhibition of ERK1/2 phosphorylation ⁽¹⁸⁾. In animal studies, eleuthero root bark was shown to exhibit neuroprotective effects against global cerebral ischemia with recovery of spatial memory in rats, possibly through anti-inflammatory mechanisms of inhibition of COX-2 expression, microglia and astrocyte expression ⁽²³⁾. Eleutherosides restored behavioral and biochemical alterations in mice with sleep deprivation ⁽²⁴⁾, and alleviated both physical and mental fatigue in mice possibly due to increased fat utilization, delayed accumulation of blood urea nitrogen, and increased lactate dehydrogenase ⁽²⁵⁾. Siberian ginseng extract also decreased cadmium concentration in the blood and liver of mice as well as cadmium-induced mitotic and apoptotic activity of liver cells ⁽²⁶⁾. Siberian ginseng supplementation reduced LDL cholesterol levels and improved LDL/HDL ratios in postmenopausal women ⁽⁷⁾. Stimulation of helper/inductor T lymphocytes and natural killer cells also occurs by an unknown mechanism ⁽¹⁾.