Ginsenoside Re

Ginsenoside Re (Ginsenoside B2) is an extract from Panax notoginseng. Ginsenoside Re decreases the β-amyloid protein (Aβ). Ginsenoside Re plays a role in antiinflammation through inhibition of JNK and NF-κB.

Ginsenoside Re is a well-known traditional Chinese medicine, which decreases the β-site amyloid precursor protein cleaving enzyme 1 (BACE1) mRNA and protein levels and inhibits BACE1 activity in the N2a/APP695 cells. Ginsenoside Re also significantly increases the PPARγ protein and mRNA levels.To prevent Ginsenoside Re from having a cytotoxic effect on the N2a/APP695 cells, the cell viability is first determined by the MTT assay. The N2a/WT and N2a/APP695 cells are treated with increasing concentrations of Ginsenoside Re (0-200 µM) for 24 h. Ginsenoside Re concentrations under 100 µM do not affect the viability of the N2a/WT and N2a/APP695 cells, whereas the 150 µM Ginsenoside Re concentration markedly decreases the survival rate of the N2a/WT and N2a/APP695 cells. Incubation with Ginsenoside Re at a 200 µM concentration for 24 h reduces the viability of the N2a/WT and N2a/APP695 cells by 15.58% and 26.82%, respectively. These data indicate that Ginsenoside Re treatment within the range of 0-100 µM for 24 h is safe for the N2a/WT and N2a/APP695 cells (P>0.05)[1].

Ginsenoside Re reduces insulin resistance in 3T3-L1 adipocytes and high-fat diet (HFD) rats through inhibition of JNK and NF-κB activation[2]. Intraperitoneal injection of lipopolysaccharide (LPS) at a dose of 20 mg/kg is lethal to mice, and 70% to 80% of the mice die within 60 h. However, pretreatment of the mice with Rg1 or Ginsenoside Re increases their survival rates in a dose-dependent manner. With the doses of Rg1 or Ginsenoside Re increase from 2.5 to 5 mg/kg, the survival rate is elevated from 60% to 90% (Rg1) or from 30% to 40% (Ginsenoside Re). All the mice administered Rg1 at a minimal dose of 10 mg/kg are protected from death compared to 80% survival of mice treated with an equal dose of Ginsenoside Re. To protect all the mice, 20 mg/kg Ginsenoside Re is needed. To investigate the anti-inflammatory potential of Rg1 and Ginsenoside Re, 1 mg/kg Rg1 or Ginsenoside Re is injected into rats and then challenged the animals with LPS. The injection procedure itself causes a transient stress-induced increase in body temperature of ~1.2°C in each group. Thereafter, LPS-challenged rats without pretreatment develope a robust biphasic fever, with the first peak reaching ~1.5°C at 2 h and the second peak reaching 1.8°C at 4 h. In contrast, the temperature changes for the Rg1-, Ginsenoside Re-, and TAK-242-treated groups are only 0.9, 1.2, and 0.8°C at 2 h and 1.3, 1.4, and 1.0°C at 4 h, respectively. Pretreatment with Rg1, Ginsenoside Re, or TAK-242 significantly attenuates LPS-induced alterations in body temperature[3].

References:
[1]. Cao G, et al. Ginsenoside Re reduces Aβ production by activating PPARγ to inhibit BACE1 in N2a/APP695 cells. Eur J Pharmacol. 2016 Dec 15;793:101-108.
[2]. Su F, et al. Protective effect of ginsenosides Rg1 and Re on lipopolysaccharide-induced sepsis by competitive binding to Toll-like receptor 4. Antimicrob Agents Chemother. 2015 Sep;59(9):5654-63.
[3]. Zhang Z, et al. Ginsenoside Re reduces insulin resistance through inhibition of c-Jun NH2-terminal kinase and nuclear factor-kappaB. Mol Endocrinol. 2008 Jan;22(1):186-95.