Findings of Russian literature on the clinical application of Eleutherococcus senticosus (Rupr. & Maxim.): A narrative review.

ETHNOPHARMACOLOGICAL RELEVANCE Eleutherococcus senticosus (Rupr. et Maxim.) Maxim (ES) (syn. Acanthopanax senticosus (Rupr. & Maxim.) Harms) is a medicinal plant used in traditional medicine of Russian Far East and East Asia and known as an adaptogen - a category of herbal medicinal products which have non-specific inter-system anti-stress effects throughout the human body. ES was first established as a medicinal plant officially in the pharmacopeia of the Union of Soviet Socialist Republics (USSR) in 1962, and is currently recommended by the European Medicines Agency (EMA) to be prescribed to treat symptoms of asthenia such as fatigue and weakness. AIM OF THE REVIEW During the time of the USSR, a distinct research directive was undertaken on ES to examine substances which improve stamina and endurance, with over 1000 studies published. Due to security measures within the former USSR these papers were not accessible to the public and were never translated into English. This is the first study to make findings of the USSR studies on ES available to the international research and scientific community. METHODS This study was an archival retrieval. References for studies were sought from printed journal and conference preceding's publications, then located within library catalogues of three libraries in St Petersburg Russia. Eligibility criteria included human clinical trials examining the efficacy of ES in any condition, published in the Russian language in the Soviet Union. RESULTS A total of 46 studies published between 1962 and 1986 in the USSR were sourced. Of the retrieved articles, 29 were reported as placebo-controlled trials, 11 were reported as controlled trials and six studies did not report the study design. Trends in studies were those reporting on healthy volunteers (n=21) at a dose of 2 ml extract/day (n=14) examining outcomes such as physical and mental stamina under varying conditions, normal work conditions, high temperatures and high altitudes, incidence or prophylaxis of colds and influenza (n=5), effects on color perception and vision (n=2), work capacity (n=1), cognitive effects (n=1), prophylaxis of hearing loss (n=3), effects on blood cell counts (n=2) and sensitivity to UV radiation (n=1). CONCLUSIONS ES appears to exhibit benefits for cognitive function and physical and mental endurance and its effect as a respiratory system infection prophylaxis treatment are promising. This study is the first to publish the findings of clinical trials on ES from the USSR, which supports the traditional use and offers a valuable contribution to the body of evidence on medicinal uses of ES when the data is applied within the context of its limitations.