Long-term treatment with standardized Ginkgo biloba extract (EGb 761) attenuates cognitive deficits and hippocampal neuron loss in a gerbil model of vascular dementia

The standardized extract of Ginkgo biloba EGb 761 has been used to reduce cognitive dysfunction. The present study was designed to evaluate the effect of postischemic oral treatment with EGb 761 in a model of vascular dementia in gerbils. Daily oral posttreatment with EGb 761 led to a significant recovery of spatial memory assessed by the object location test, inhibited the decrease in plasma SOD activity and protected the hippocampal CA1 neurons, even when administered after the insult. These data provide further evidence for the therapeutic potential of EGb 761 in the treatment of vascular dementia.     

In vitro metabolism in Sprague-Dawley rat liver microsomes of forsythoside A in different compositions of Shuang-Huang-Lian

Shuang–Huang–Lian (SHL), a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. Forsythoside A is one of the main active ingredients in Forsythiae fructus, a key herb in SHL. In the present study, effects of different compositions in SHL on the in vitro metabolism in Sprague–Dawley rat liver microsomes of forsythoside A were investigated. The observations from Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA that forsythoside A may be the substrates of CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3, UGT1A1 and UGT1A9; Chlorogenic acid may be the substrates of CYP3A4, CYP2C9, CYP1A2, CYP2C19, UGT1A6, UGT1A3 and UGT1A1; Baicalin may be the substrates of CYP3A4, CYP2C19, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; Baicalein may be the substrates of CYP3A4, CYP2E1 and UGT1A6. It was also found that the residue of forsythoside A in SHL, FF + LJF and FF + SR was greatly increased compared with that in FF in Sprague–Dawley rat liver microsomes in the presence of β-NADPH or UDPGA, which indicated that the metabolism of forsythoside A in SHL may be influenced by chlorogenic acid in LJF acting on the CYP3A4, CYP2C9, CYP1A2, UGT1A6, UGT1A3 and UGT1A1; baicalin in SR acting on the CYP3A4, CYP1A2, UGT1A9, UGT1A1 and UGT1A3; baicalein acting on the CYP3A4 and UGT1A6 respectively.