The objectives of this study are to conduct a comprehensive literature search and bibliometric analysis to identify the breadth and volume of pharmacological and clinical studies on pine pollen (Pinus pollen) and to identify the potential effects and the use of pine pollen. Three Chinese electronic databases and two English electronic databases were searched for pharmacological and clinical studies on pine pollen. Data were extracted and analyzed and included publication year, authors, study type, pharmacological research topics or clinical diseases/conditions, usage and type of preparation, authors' conclusions, and adverse effects. Of 239 publications identified, 180 were pharmacological studies, 37 were clinical trials, and 22 were reviews. Numbers of publications increased particularly from 2004 onward. The top 10 most frequent topics in pharmacological studies were immune regulation, antisenility, antioxidation, liver protection, inhibiting prostate hyperplasia, inhibiting tumor cell proliferation, lowering blood glucose, lowering blood lipids, antifatigue, and improving intestinal function. The top 10 most frequent clinical diseases treated or where pine pollen was used as an adjuvant were bedsores, diaper dermatitis, hyperlipidemia, oral mucositis, eczema, hyperplasia of prostate, hypertension, prostatitis, type 2 diabetes mellitus, and radiodermatitis. Eight trials reported no adverse events associated with pine pollen, one reported mild gastrointestinal reactions, but symptoms disappeared without special management. There have been an increasing number of publications on pine pollen during the past 20 years. Pharmacological studies have shown many potential benefits, and clinical studies have indicated some positive effects when it is either used as a single herb or as an adjuvant to treat disease. Its use as a topical agent, especially for skin diseases, was notable.
Keywords: Bibliometric analysis; Chinese herbal medicine; Pinus pollen; pine pollen; skin disease.