G. j. var. Thunberg
Geum japonicum is a yellow-flowering perennial plant native to North America and East Asia, especially Japan. It may be synonymous with Geum macrophyllum, the North American flower. As a traditional herbal remedy it is known as an astringent and used in poultices. However, in recent years, the Thunberg variant has received attention for other possible medical uses.
With regard to muscular recovery, an extract has been found to help muscles recover following "severe injury", to reduce myocardial infarct size by 35-45% when administered following a heart attack, and to inhibit apoptosis. It also has possible anti-viral properties, including action against HIV  and HSV. Action against tumors has also been noted.
- Geum japonicum. Plants for a Future. Retrieved April 27, 2012, from http://www.pfaf.org/user/Plant.aspx?LatinName=Geum+japonicum
- Cheng et al. (2006). A new function of a previously isolated compound that stimulates activation and differentiation of myogenic precursor cells leading to efficient myofiber regeneration and muscle repair. Int J Biochem Cell Biol. 2006;38(7):1123-33. PMID 16431151
- Li et al. (2006). Repair of infarcted myocardium by an extract of Geum japonicum with dual effects on angiogenesis and myogenesis. Clin Chem. 2006 Aug;52(8):1460-8. PMID 16873297
- Gu et al. (2007). Neovascularization of ischemic myocardium by newly isolated tannins prevents cardiomyocyte apoptosis and improves cardiac function. Mol Med. 2006 Nov-Dec;12(11-12):275-83. PMID 17380192
- Kageyama et al. (1996). Potent activity of the extract of Geum japonicum Thunb. For the prophylaxis of cytomegalovirus infection in AIDS patients. Int Conf AIDS. 1996 Jul 7-12; 11: 65. Retrieved August 8, 2008, from http://gateway.nlm.nih.gov/MeetingAbstracts/ma?f=102217030.html
- Xu, Ming, Dong, & Butt. (2000). A new anti-HIV triterpene from Geum japonicum. Chem Pharm Bull (Tokyo). 2000 Sep;48(9):1367-9. PMID 10993241
- Kurokawa et al. (1998). Purification and characterization of eugeniin as an anti-herpesvirus compound from Geum japonicum and Syzygium aromaticum. J Pharmacol Exp Ther. 1998 Feb;284(2):728-35. PMID 9454821
- Heo et al. (2008). A fraction of methylene chloride from Geum japonicum Thunberg inhibits tumor metastatic and angiogenic potential. Oncol Rep. 2008 Jun;19(6):1399-403. PMID 18497943