Liquiritin

Liquiritin is a flavanone glycoside derived primarily from licorice root (Glycyrrhiza uralensis) that exerts antidepressant, anti-inflammatory, and neuroprotective effects. Its primary mechanisms involve inhibition of the NLRP3 inflammasome, modulation of serotonin and dopamine pathways, and suppression of NF-κB-driven cytokine release.

Origin & History

Liquiritin is a flavonoid glycoside derived from the roots of Glycyrrhiza uralensis, commonly known as Chinese licorice. It is produced through extraction and purification processes from licorice root, such as the Herbpurify method.

Historical & Cultural Context

Liquiritin originates from the licorice root, used in Traditional Chinese Medicine for thousands of years as an immunomodulatory agent. Historically, it has been applied to treat inflammation and stress-related conditions.

Health Benefits

• Reduces depression-like behaviors in mice models, as demonstrated in chronic unpredictable mild stress studies (PMID: 35069768).
• Decreases lung edema and inflammation in LPS-induced acute lung injury in mice (no PMID in snippet).
• Attenuates NLRP3 inflammasome-triggered cytokines, reducing depressive symptoms (PMID: 35069768).
• Provides anti-oxidative effects by increasing SOD and reducing lipid peroxidation (PMID: 35069768).
• Modulates immune responses, traditionally used for stress-related conditions (historical use).

How It Works

Liquiritin suppresses NLRP3 inflammasome activation, thereby reducing downstream release of pro-inflammatory cytokines IL-1β and IL-18, which are implicated in neuroinflammation-driven depression. It also upregulates serotonin (5-HT) and dopamine (DA) neurotransmitter levels in the prefrontal cortex and hippocampus, likely through inhibition of monoamine oxidase (MAO) activity. Additionally, liquiritin attenuates NF-κB nuclear translocation, reducing expression of TNF-α and IL-6 in peripheral inflammatory conditions such as acute lung injury.

Scientific Research

There are no human clinical trials or meta-analyses available for liquiritin. Evidence is based exclusively on preclinical animal and in vitro studies. Notably, in one study, liquiritin was administered to mice in a chronic unpredictable mild stress model, showing significant behavioral improvements (PMID: 35069768).

Clinical Summary

Current evidence for liquiritin is based almost entirely on preclinical animal models, with no large-scale human clinical trials published as of 2024. In chronic unpredictable mild stress (CUMS) mouse models, liquiritin administration significantly reduced depression-like behaviors as measured by the sucrose preference test and forced swim test (PMID: 35069768). Separately, mouse models of LPS-induced acute lung injury showed that liquiritin decreased lung edema, reduced inflammatory cell infiltration, and lowered NLRP3-associated cytokine levels. The evidence is promising but remains at an early stage; human pharmacokinetic and efficacy data are needed before clinical recommendations can be made.

Nutritional Profile

Liquiritin is a flavanone glycoside (flavonoid-O-glycoside) isolated primarily from Glycyrrhiza uralensis (licorice root), consisting of a liquiritigenin aglycone bound to a glucoside moiety. It is not a macronutrient source and contains no meaningful protein, fat, or dietary fiber in its isolated compound form. As a bioactive phytochemical, it is typically studied at concentrations of 20–80 mg/kg in rodent models. It exhibits antioxidant activity by upregulating superoxide dismutase (SOD) and reducing lipid peroxidation markers (MDA). Its bioavailability is moderate; the glycoside form undergoes intestinal hydrolysis by gut microbiota to release the active aglycone liquiritigenin, which has better membrane permeability. No clinically established human dosage is confirmed. Trace minerals or vitamins are not intrinsic to the isolated compound. It also modulates serotonin (5-HT) and norepinephrine (NE) pathways, which underlies its antidepressant-like activity.

Preparation & Dosage

In preclinical models, liquiritin was administered intraperitoneally at 40 mg/kg daily for 4 weeks for depression models and 40-80 mg/kg daily for 7 days for acute lung injury models. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Liquiritin pairs well with (1) Glycyrrhizin (co-constituent of licorice root), which enhances anti-inflammatory effects through complementary NF-κB suppression and amplifies NLRP3 inflammasome inhibition alongside liquiritin's cytokine-attenuating action. (2) Berberine synergizes via additive antidepressant mechanisms — both compounds modulate monoamine neurotransmitter levels (5-HT, NE, dopamine) through distinct but parallel pathways, and berberine's AMPK activation complements liquiritin's oxidative stress reduction. (3) Curcumin enhances the anti-inflammatory and antioxidant stack by independently upregulating Nrf2/HO-1 signaling while liquiritin boosts SOD activity, creating a dual-pathway antioxidant effect; additionally, piperine (from black pepper) can improve curcumin bioavailability in a combined formulation. (4) Quercetin acts additively on NLRP3 inflammasome suppression and shares the flavonoid structural class with liquiritin, supporting complementary gut microbiota metabolism to active aglycone forms that enhance systemic antioxidant capacity.

Safety & Interactions

Liquiritin's specific human safety profile has not been formally established in controlled clinical trials, though it is generally considered low-toxicity in animal studies at tested doses. Because it is derived from licorice (Glycyrrhiza species), caution is warranted in individuals sensitive to licorice compounds; unlike glycyrrhizin, liquiritin itself does not appear to cause pseudohyperaldosteronism, but isolated compound safety data are limited. Potential drug interactions include additive effects with MAO inhibitors or serotonergic drugs due to its monoaminergic activity, and co-administration with anti-inflammatory medications or corticosteroids warrants caution given overlapping NF-κB inhibition pathways. Pregnancy and lactation safety has not been studied; use is not recommended in these populations without medical supervision.