title: Polyphenolic glycosides isolated from Pogostemon cablin (Blanco) Benth. as novel influenza neuraminidase inhibitors.
abstract: BACKGROUND
  Influenza is historically an ancient disease that causes annual epidemics and, at irregular intervals, pandemics. At present, the first-line drugs (oseltamivir and zanamivir) don't seem to be optimistic due to the spontaneously arising and spreading of oseltamivir resistance among influenza virus. Pogostemon cablin (Blanco) Benth. (P. cablin) is an important traditional Chinese medicine herb that has been widely used for treatment on common cold, nausea and fever. In our previous study, we have identified an extract derived from P. cablin as a novel selective neuraminidase (NA) inhibitor.
  
  
  RESULTS
  A series of polyphenolic compounds were isolated from P. cablin for their potential ability to inhibit neuraminidase of influenza A virus. Two new octaketides (1, 2), together with other twenty compounds were isolated from P. cablin. These compounds showed better inhibitory activity against NA. The significant potent compounds of this series were compounds 2 (IC50 = 3.87 ± 0.19 μ mol/ml), 11, 12, 14, 15, 19 and 20 (IC50 was in 2.12 to 3.87 μ mol/ml), which were about fourfold to doubled less potent than zanamivir and could be used to design novel influenza NA inhibitors, especially compound 2, that exhibit increased activity based on these compounds. With the help of molecular docking, we had a preliminary understanding of the mechanism of the two new compounds (1-2)' NA inhibitory activity.
  
  
  CONCLUSIONS
  Fractions 6 and polyphenolic compounds isolated from fractions 6 showed higher NA inhibition than that of the initial plant exacts. The findings of this study indicate that polyphenolic compounds and fractions 6 derived from P. cablin are potential NA inhibitors. This work is one of the evidence that P. cablin has better inhibitory activity against influenza, which not only enriches the compound library of P. cablin, but also facilitates further development and promises its therapeutic potential for the rising challenge of influenza diseases.
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Fang
authors: F
authors: Liu
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Wei
authors: W
authors: Cao
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Chao
authors: C
authors: Deng
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Zhaoquan
authors: Z
authors: Wu
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Guangyao
authors: G
authors: Zeng
authors: College of Pharmacy, Central South University, Changsha, 410013 Hunan People's Republic of China.
authors: Yingjun
authors: Y
authors: Zhou
keywords: Neuraminidase (NA) inhibitory activity; Octaketide; Pogostemon cablin (Blanco) Benth.; Polyphenolic glycosides