A new effective strategy for treating tobacco addiction was developed by researchers from the CAS

The tobacco addiction epidemic is a major public health problem worldwide. Professor Zhao Baolu and his group from the State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences set out to tackle this problem. After 20 years of innovative research, they have developed a novel tea filter to treat cigarette addiction and have discovered the molecular mechanism behind the smoking cessation effect. They identified theanine as the active ingredient in the tea filter that inhibits nicotine addiction. Their work entitled "The cessation and detoxification effect of tea filters on cigarette smoke" was published in the X. edition Science of China in 2010.

Cigarette smoking has been linked to many life threatening diseases including heart disease, cancer and chronic obstructive pulmonary disease. There are about 1.25 billion smokers in the world and five million die every year because of smoking-related diseases, exceeding many other diseases combined.

It is estimated that the global cost for smoking-related diseases is about $200 billion each year, resulting in one of the world's largest human public health problems. Many methods have been developed for smoking cessation by researchers and clinicians. Despite all efforts, currently available smoking cessation methods produce only modest success rates with frequent relapse. Due to the addictive nature of nicotine, quitting smoking remains an extremely difficult task. Therefore, the need for developing new smoking cessation strategies with better efficacy and fewer side effects is urgent.

Human tests using a newly developed tea filter were conducted at the Addiction Branch of Beijing Military Region General Hospital. A total of more than 100 male smokers participated in this study.

The results from the first trial showed that the participants' average daily cigarette consumption decreased by about 43% and 56.5% after using the tea filters for 1 and 2 months, respectively. The results from the second trial showed that the participants' average daily cigarette consumption decreased by about 48%, 83% and 91% after using the tea filters for 1, 2 and 3 months, respectively. The average daily cigarettes consumed by the participants decreased from about 24.5 per day to about 3 per day at the end of 3 months of treatment. In addition, most participants indicated that sputum and their smoking-related symptoms were reduced compared with the control group. Physical examinations of the participants did not reveal any apparent side effects.

The mechanism of action (MOA) studies indicated that theanine in the filter exerted an inhibitory effect similar to the nicotine acetylcholine receptor (nAChR) inhibitor. In addition, theanine could significantly inhibit the nicotine-induced increased expression of nAChR and the increase of the neurotransmitter dopamine (DA) released in mouse brains. The toxicological studies showed that the tea filters could significantly reduce the carcinogenic materials such as tar, free radicals, nitrosamine, benzo[a]pyrene, benzo[a]anthracene, chrysene and total polycyclic aromatic hydrocarbons (PAHs) generated in cigarette smoking. Animal studies also revealed that tea filters could significantly reduce the acute toxicity, mutagenicity, lung damage and carboxyhemoglobin (COHb) levels in the blood caused by cigarette smoking.