DOI: 10.36347/sjavs.2022.v09i03.001

Pages: 29-34

Gamma‐aminobutyric acid (GABA) is the major inhibitory neurotrans-mitter in the central nervous system, being GABAAreceptors a target for anaesthetics and neuroleptic, anxiolytic, and anticonvulsant com-pounds. G. glabra acts as a modulator of GABAA receptors, being able to induce sedative and anxiolytic effects. Glabridin potentiated GABA‐induced responses by positive modulation of GABAA receptors, exhibiting sedative and hypnotic effects. Glabridin potentiation is not sensitive to flumazenil and uses a similar mechanism of the general anaesthetics involving the amino acids N265 and M286, which are located in the second and third transmembrane domains on the β‐subunit of GABAA receptors. Glabridin could also contribute to the hypnotic effect, as it is able to cross the blood–brain barrier. Liquorice extract has potential therapeutic value for the treatment of depressive disorders. Liquo-rice extract produces significant antidepressant effects. The main skin benefits reported for G. Glabra are based on the antiox-idant and anti‐inflammatory activities as well as on the ultraviolet (UV) protection. Mainly liquorice is used for skin eruptions, including dermatitis, eczema, pruritus, and cysts. G. glabra flavonoids present depigmenting capabilities and tyrosi-nase inhibition effects. The presence of anα‐keto group in flavonoids is responsible for the skin protective effects of liquorice against damage from oxidative stress. Liquo-rice extract can scavenge DPPH free radicals with an inhibition of 80% and protect fibroblasts against oxidative stress. Nevertheless, when evaluated in the isolated form, glycyrrhizin showed a poor antioxidant activity, being not able to efficiently coun-teract the oxidative effect. Tyrosinase is essential for skin pigmentation due to its role in melanin biosynthesis. The use of tyrosinase inhibitors is important in the cosmetic and medicinal industries, due to their pre-ventive effect on pigmentation disorders such as melasma, age spots, ...