Chinese Scientists Claim Extremely Novel Finding After First Natural Product Found To Target Influenza A Viruses
The high mutability of pathogenic Influenza A viruses (IAVs) enables them to become resistant to various preventive treatments, however Honeysuckle (HS, Lonicera japonica), a well-known Chinese herb, has been used to effectively treat influenza infection for thousands of years and now a study by Chen-Yu Zheng and colleagues at Nanjing University are providing evidence how the herb directly targets IAVs.
Chinese scientists are claiming an 'extremely novel finding' after their published research in journal Cell Research which is the first to identify the active component in Traditional Chinese Medicine to directly target various IAVs and may represent a novel type of natural product that effectively suppresses viral infection.
Honeysuckles are valued as garden plants, for their ability to cover unsightly walls and outbuildings, their profuse tubular flowers in summer, and the intense fragrance of many varieties. The hardy climbing types need their roots in shade, and their flowering tops in sunlight or very light shade.
Most honeysuckle berries are attractive to wildlife, which has led to species such as L. japonica and L. maackii spreading invasively outside of their native range, particularly in New Zealand and the United States.
The study by Chen-Yu Zheng and colleagues at Nanjing University -- 'Honeysuckle-encoded atypical microRNA2911 directly targets influenza A viruses (IAVs)', appears in the journal Cell Research today.
Zheng et al. note that the Chinese have drunk honeysuckle (Lonicera japonica) tea to treat influenza viral infections for thousands of years.
"Several reports have shown that honeysuckle decoctions can suppress the replication of the influenza virus," the academics write, citing Ko et al. (2006) and Zhang et al. (2012).
"However, the active compounds in honeysuckle decoction and the mechanism by which they block viral replication have remained unclear," they add.
Effective Therapy to Subdue Deadly IAV Infections
Zheng et al. say their study identifies MIR2911 (plant microRNA* regulates the expression of 'messenger' RNAs) as the first active component directly targeting influenza A viruses.
"In conclusion, the present study provides the first evidence that the highly stable plant MIR2911 can directly target multiple vital genes of various IAVs and thus suppress viral infections," they write.
"With its broad-spectrum, anti-viral activity against IAVs, MIR2911 and a MIR2911-containing honeysuckle decoction may represent a new effective therapeutic strategy that can be used to subdue deadly IAV infections," the authors add.
"Since Fleming discovered penicillin nearly a century ago, antibiotics have been developed to target various bacterial infections and have saved the lives of millions of people," they write.
"Unfortunately no natural product that is effective against viral infection has been identified so far," the scientists add.
First Natural Product To Directly Target Influenza A Viruses
"We suggest that as the first natural product to directly target IAVs, MIR2911 is the virological penicillin that serves as a novel therapeutic and preventive agent against not only influenza A but potentially also other types of virus," write Zheng et al.
MIR2911 was selectively retained in a boiled decoction of honeysuckle drunk by mice, and delivered by this means into their plasma and lung tissue.
The authors write that MIR2911 works to suppress influenza viruses by targeting PB2 and NS1 -- two genes that the viruses require to replicate.
The team found that both synthetic and natural MIR2911 in the honeysuckle tea effectively protected the mice from H1N1, H5N1 and H7N9 (so called 'bird flus'), -- indicating its wide-ranging effectiveness against IAVs.
RNA viruses can have high mutation rates compared to DNA viruses. miRNAs are small RNAs -- polymeric molecules that de-code, regulate and determine gene expression. The leap of small RNAs from laboratory into the marketplace in identifying components in natural products is ongoing, and much of what has been learned in the past few years is acting as a springboard to further the exact mechansims on the effectiveness of natural medicine.