Licorice first appeared in the "Shennong Herbal Classic", also known as pink grass, honey grass, beautiful grass, is the leguminous licorice plant licorice (also known as Urallicorice) dried roots and rhizomes. Harvest in spring and autumn for raw or honey roasting. Traditional Chinese medical science saying that "ten directions and nine grasses", here "grass" refers to licorice. Licorice is mild, cold and heat tonic，and cathartic all kinds of drugs used together, can moderate the intensity or reduce the toxic side effects, has the power of harmonizing 100 drugs, therefore it is also known as "the lord of the country", "the king of detoxification".

Recent studies have shown that glycyrrhizin, glycyrrhizic acid, glycyrrhetinic acid, glycyrrhizin and other glycyrrhizin extracts have antioxidant, anti-inflammatory, antiviral, anti-tumor and other pharmacological effects, and are one of the most promising anti-aging Chinese herbal medicines.

Senescence is every tissues and organs of the body grows old with age, lead to irreversible degenerate change of the structure and function gradually ,under the influence of many factors such as in vivo and in vitro heredity, mental stress and environmental pollution. Licorice and its active ingredients can play an antioxidant role by fighting oxidative stress in the body. The first is to inhibit the production of reactive oxygen species, a general term for active oxygen-containing biochemicals in the body that are considered to be associated with aging. Liquiritin in licorice reduces the production of reactive oxygen species by reducing the expression of related adhesion molecules.

In addition, on the basis of raw licorice, honey processing can be used to obtain licorice, which can reduce the oxidative stress damage induced by metronidazole and inhibit the production of excessive reactive oxygen species induced by azodiisobuamidine hydrochloride.

The second is to capture free radicals, which are produced by cells during aerobic respiration and have the functions of signal transmission and etc. There are research have shown that the molecular mechanism of scavenging oxygen free radicals in licorice green tea beverage has been clarified , by network pharmacology, molecular docking technology, in vitro scavenging free radical experiments, oxidative stress damage of human permanent biochemical keratinocytes induced by hydrogen peroxide, mouse aging model induced by D-galactose, and protein imprinting experiments.

Liquorice anti-aging active ingredient

Glycyrrhizone A

Glycyrrhizone A is a chalcone substance derived from licorice root, has the bioactive functions ,and used as an anti-tumor, antioxidant, anti-obesity and neuroprotective agent. It has been found that glycyrtinone A has anti-obesity effect by inhibiting the proliferation of glioma stem cells, inhibits thrombosis, and has anti-aging effect by regulating the nuclear factor erythrocytic 2-associated factor 2 (Nrf2). This anti-aging effect may be related to the direct effect of glycyrrhizone A on mesenchymal stem cells (ADscs), which is capable of anti-aging and may alleviate or even avoid many diseases associated with aging.

Dipotassium glycyrrhizinate

Dipotassium glycyrrhizinate is a derivative of glycyrrhizic acid in glycyrrhizin extract. It has the functions of anti-inflammation, anti-sensitivity, antibacterial, wound treatment, and effective removal of superoxide ions and hydroxyl radicals. Potassium glycyrrhizinate also has a proliferative effect on muscle cells, a proliferative effect on vascular endothelial cells, and a stimulant effect on the synthesis of type 4 collagen.

glabridine

Glycyrrhizin is the main active ingredient of glycyrrhizin extract, which is a flavonoid compound. It has passed the safety test of human skin irritation by the US FDA and has been certified as a harmless skin care ingredient in nature without teratogenic factors. From the inhibition of tyrosinase and dopa pigment tautomase to prevent melanin generation, inhibition of cyclooxygenase activity anti-inflammatory, scavenging oxygen free radical antioxidant three aspects, to achieve whitening and anti-aging effect. Glycyrrhizin has a strong ability to remove oxygen free radicals, and can effectively slow down the sub-health conditions such as pigmentation and skin roughness caused by the oxidation of low-density lipoprotein in the blood vessels, so as to delay the effect of skin aging.

Liquorice flavonoids

Flavonoids in licorice also have certain anti-aging effects. Glycyrrhiza flavanones belong to phenolic substances and are a class of secondary metabolites in glycyrrhiza. A total of 115 flavonoids were found in Uralglycyrrhiza, glycyrrhiza glabrata, glycyrrhiza distencia and other commonly used glycyrrhiza, including isoglycyrrhiza flavonol, glycyrrhiza glabrata and glycyrrhiza chalketone A. These compounds have a variety of pharmacological activities, such as anti-tumor, anti-inflammation, anti-oxidation, anti-diabetes, anti-cancer, etc. These effects may be related to their anti-aging activities. Flavonoids are excellent active oxygen scavenger and lipid antioxidant, which can react with superoxide anion to prevent free radical reaction, complex with iron ion to prevent hydroxyl radical formation, and react with lipid peroxidation group to prevent lipid peroxidation process.

Multi-system performance of licorice’anti-aging

nervous system

Licorice can enhance the immune function of the nervous system, improve the disease resistance of the nerves, and strengthen the conditioning for those with serious diseases. Modern pharmacological research shows that licorice also has a calming effect, helping to relieve nervous tension and anxiety. Some researchers have found that the neuroprotective mechanism of liquiritin is related to the regulation of metabolic disorders, activation of Nrf2-Keap1 pathway, inhibition of ERK1/2-NF-κB pathway, and inhibition of mitochondrial apoptosis pathway. That is, by reducing intracellular calcium concentration, improving mitochondrial membrane matrix, up-regulating the expression of Bcl2, down-regulating the expression levels of Bax, cytochrome C and lysteine aspartase 3, thereby inhibiting mitochondrial apoptosis and protecting the nervous system. Other studies have shown that liquiritin maintains the integrity of the blood-brain barrier by inhibiting oxidative stress and endoplasmic reticulum stress.

Cardiovascular system

Licorice has the effect of improving cardiovascular function, can protect the health of the heart and blood vessels. Related studies have shown that glycyrrhizin has a protective effect on myocardial injury in diabetic rats. The specific mechanism is that GL reduces the expression of phosphorylated p38MAPK, glycosylated end-product receptor (RAGE), Na(V)1.5 and transforming growth factor -β in myocardial tissue by activating Nrf2, inhibiting CXCR4/SDF1 and transforming growth factor -β signaling pathway. The expression of gap connexin 43(CX43), CXC chemokine receptor 4(CXCR4), Nrf2 and troponin Ⅰ were changed.

However, because some components in licorice may cause water and sodium retention and high blood pressure, caution is needed when using licorice in patients with cardiovascular system diseases.

Respiratory system

Licorice has the function of moistening lung and relieving cough, and can be used to treat respiratory diseases such as cough, asthma and bronchitis.

Glycyrrhizic acid in licorice relaxes the bronchus, reduces sputum secretion, and suppresses inflammation, thus relieving respiratory symptoms. Glycyrrhizin alleviates endoplasmic reticulum stress mediated by oxidative stress and pyrodeath mediated by NLRP3 inflammation through antioxidant Nrf2 signaling pathway, which may be a future treatment direction for lung injury caused by particulate matter.

digestive system

Licorice has the functions of tonifying spleen and qi, clearing heat and detoxifying, and can be used to treat digestive system diseases such as spleen and stomach weakness, indigestion, gastritis, gastric ulcer and enteritis. Glycyrrhizic acid and other ingredients in licorice can relieve gastrointestinal cramps and inflammation, promote ulcer healing, and protect gastrointestinal mucosa.

Other systems

Licorice can delay the aging of skin and sensory system. The gel prepared with glycyrrhizic acid and paeony glycoside as the main effective components has obvious preventive effect on melasma caused by progesterone injection and UV-B irradiation, and can also reduce the skin inflammation of the back of melasma model rats and reduce the loss of collagen fibers, which undoubtedly provides a new potential therapeutic direction for the future prevention and treatment of melasma.

As a typical Chinese herbal medicine, licorice already been used for about 2000 years. With the increasing aging of the population, the research and development of anti-aging drugs has broad development prospects. Modern medical means have confirmed the potential of licorice in anti-aging, but further research still needed to clarify its biosafety, pharmacokinetics and bioavailability in the future.