Lingzhi (Ganoderma lingzhi) and Immune support: evidence and sources

The mushroom Ganoderma lucidum (G. lucidum) has been used for centuries in Asian countries to treat various diseases and to promote health and longevity. Clinical studies have shown beneficial effects of G. lucidum as an alternative adjuvant therapy in cancer patients without obvious toxicity. G. lucidum polysaccharides (GLP) is the main bioactive component in the water soluble extracts of this mushroom. Evidence from in vitro and in vivo studies has demonstrated that GLP possesses potential anticancer activity through immunomodulatory, anti-proliferative, pro-apoptotic, anti-metastatic and anti-angiogenic effects. Here, we briefly summarize these anticancer effects of GLP and the underlying mechanisms.

Medicinal mushrooms are rich sources of pharmacologically active compounds. One of the mushrooms commonly used in traditional Chinese medicine is Ganoderma lucidum (Leyss. Ex Fr.) Karst. In Asian countries it is treated as a nutraceutical, whose regular consumption provides vitality and improves health. Ganoderma lucidum is an important source of biologically active compounds. The pharmacologically active fraction of polysaccharides has antioxidant, immunomodulatory, antineurodegenerative and antidiabetic activities. In this review, we summarize the activity of Ganoderma lucidum polysaccharides (GLP).

Ganoderma lucidum is an edible medicinal mushroom known as "Lingzhi" in China and "Reishi or Manetake" in Japan. It is a highly prized vitality-enhancing herb for >2000 years. G. lucidum polysaccharide (GLPS) has been identified as one of the major bioactive components and developed into a drug named "Ji 731 Injection" in China since 1973. The large-scale production of the drug began in 1985 and approved by the Chinese FDA as "Polysacharidum of G. lucidum Karst Injection in 2000, which is applied intramuscularly. After more than 40 years of clinical use, its efficacy, safety, and long-term tolerability have been recognized by neurologists. It is one of a few non-hormonal drugs used for treating neurosis, polymyositis, dermatomyositis, atrophic myotonia and muscular dystrophy. It is also used for combination therapy, which reduces the amount of glucocorticoid required for myopathy patient who is in remission. In addition, it reduces adverse reactions and improves the quality of life for cancer patients during chemotherapy. We found 81 qualified chemical, biochemical, preclinical, and clinical studies of GLPS both in English and Chinese spanning from 1973 to 2017 by searching CNKI (China National Knowledge Infrastructure), Wan Fang, and PubMed databases. The molecular mechanisms underlying GLPS's antioxidant, anti-tumor, immune-modulatory, hypoglycemic, hypolipidemic, and other activities are discussed. Both preclinical and clinical studies are either deliberated or indexed in current article. We aimed to provide a molecular picture as well as a clinical basis to comprehend GLPS as one of few polysaccharide-based modern medicines with complicated chemical and pharmacological properties.

Ganoderma lucidum (G. lucidum), a basidiomycete white rot fungus, has long been prescribed to prevent and treat various human diseases, particularly in China, Japan, and Korea. Several classes of bioactive substances have been isolated and identified from G. lucidum, such as triterpenoids, polysaccharides, nucleosides, sterols, and alkaloids, among others. This paper examines the potential role of G. lucidum polysaccharide (GLPS) in tumor therapy and the possible mechanisms involved. Both in vitro and in vivo studies suggested that the anti-tumor activities of GLPS are mediated by its immunomodulatory, anti-angiogenic, and cytotoxic effects. GLPS affects immune cells and immune-related cells including B lymphocytes, T lymphocytes, dendritic cells, macrophages, and natural killer cells. In addition, recent data also suggest that GLPS suppresses tumorigenesis or inhibits tumor growth through direct cytotoxic effect and anti-angiogenic actions. However, many questions still need to be answered before both G. lucidum and GLPS can be widely accepted and used as anti-tumor agents.

In Asia, a variety of dietary products have been used for centuries as popular remedies to prevent or treat different diseases. A large number of herbs and extracts from medicinal mushrooms are used for the treatment of diseases. Mushrooms such as Ganoderma lucidum (Reishi), Lentinus edodes (Shiitake), Grifola frondosa (Maitake), Hericium erinaceum (Yamabushitake), and Inonotus obliquus (Chaga) have been collected and consumed in China, Korea, and Japan for centuries. Until recently, these mushrooms were largely unknown in the West and were considered 'fungi' without any nutritional value. However, most mushrooms are rich in vitamins, fiber, and amino acids and low in fat, cholesterol, and calories. These mushrooms contain a large variety of biologically active polysaccharides with immunostimulatory properties, which contribute to their anticancer effects. Furthermore, other bioactive substances, including triterpenes, proteins, lipids, cerebrosides, and phenols, have been identified and characterized in medicinal mushrooms. This review summarizes the biological effects of Ganoderma lucidum upon specific signaling molecules and pathways, which are responsible for its therapeutic effects.