Compound from Vietnamese herb shows promise in fight against sarcopenia
Gynostemma longipes is little used in herbal products in the West. The herb is called commonly called “That diep dom,” used in the Vietnamese herbal medicine tradition in tonics for treatment of diabetes and health strengthening.
A leaf extract from a related species, Gynostemma pentaphyllum, forms the basis of ActivAMP, an extract made by Gencor Pacific that is featured in a wide range of commonly sold dietary supplements marketed for muscle health and vitality.
Sarcopenia is a rapidly expanding area of anti aging research. The term has been used in a somewhat amorphous fashion to basically refer to muscle wasting and weakness among older people that impairs quality of life and can raise the risk of things like falls and fractures.
Recently, there has been an attempt to define this condition in a more clinically relevant fashion. “It was recognized that the key element was a loss of muscle strength (dynapenia) rather than a loss of muscle mass. This has led to a change in the definition of sarcopenia to include strength (grip strength) or function (walking speed or distance),” said the authors of a 2014 paper on the subject.
Those authors put the prevalence of sarcopenia at about 5% to 10% of people over 65 years of age. According to recent statistics, more than 600 million people, or more than 8% of the world’s population, are now 65 years old or older. By 2050, that number is expected to grow to 1.6 billion, or as much as 15% of the world’s population. So as many as 60 million people may be exhibiting signs of sarcopenia today, with as many as 160 million in 30 years.
Eight new compounds isolated
In the Gynostemma longipes paper, researchers associated with institutions in South Korea, Vietnam and China isolated and characterized eight new 12,23-dione dammarane triterpenoids, as well as one known gypentonoside A from Gynostemma longipes and tested them in a mouse muscle cell line.
They were looking for the effects of the compounds on AMP-activated protein kinase (AMPK), an essential sensor and regulator of glucose, lipid and energy metabolism throughout the body and one that plays a vital role in muscle cell regeneration. The researchers chose the particular muscle cell line for its relevance to the development of sarcopenia.
“Regeneration of damaged skeletal muscles depends on satellite cells (known as quiescent muscle precursor cells), which play an important role in the proliferation and differentiation of myoblasts to form or repair muscle fibers. Recently, several studies have demonstrated that decreased proliferation of myoblasts and cytotoxicity can reduce the number of muscle fibers. Therefore, mouse C2C12 cells, also known as myoblastic cells, were chosen in this research because they are a valid model to study muscle cell proliferation,” they wrote.
Could common backbone of compounds be the deciding factor?
The researchers found significant effects on the AMPK pathway for seven of the eight newly isolated compounds. But only one of these is found in significant concentration in the plant, which the researchers referred to simply as compound 1. But the fact that almost all of the closely related compounds showed some activity led them to speculate that the backbone of these compounds is the important structural element.
“Considering the structures and activities of all nine isolates, the core structure of the dammarane skeleton might contribute mainly to the AMPK activation effect,” they wrote.
“A considerable amount of active compound 1 (over 2.08% per dried raw plant) in G. longipes suggested that it may be a promising candidate for development of functional food or botanical drug. These results also indicated that new dammarane-type compounds are promising candidates for muscle proliferation via activation of AMPK signaling pathways and could be further studied and developed as therapeutics for geriatric diseases,” they concluded.
Source: Scientific Reports
“12,23-Dione dammarane triterpenes from Gynostemma longipes and their muscle cell proliferation activities via activation of the AMPK pathway”
Published online 2019 Feb 4. doi: 10.1038/s41598-018-37808-9
Authors: Ha TKQ, Pham HTT, Cho HM, et al.