Prevention of alcohol-induced DNA damage by a proprietary glycyrrhizin/D-mannitol product: A randomized, placebo-controlled, cross-over human study

The genus Glycyrrhiza (Fabaceae family) and its active constituents as protective agents against natural or chemical toxicities

Licorice is the dried roots and rhizomes of various species of the genus Glycyrrhiza (Fabaceae) that have been used in folk medicine from ancient times. Many important research projects have established several beneficial effects for this medicinal herb, including antiinflammatory, antimicrobial, antiviral, antiprotozoal, antioxidant, antihyperglycemic, antihyperlipidemic, hepatoprotective, and neuroprotective. Licorice contains important bioactive components, such as glycyrrhizin (glycyrrhizic, glycyrrhizinic acid), liquiritigenin, liquiritin, and glycyrrhetinic acid. The protective effects of licorice and its main chemical components against toxins and toxicants in several organs including the brain, heart, liver, kidney, and lung have been shown. In this comprehensive review article, the protective effects of these constituents against natural, industrial, environmental, and chemical toxicities with attention on the cellular and molecular mechanism are introduced. Also, it has been revealed that this plant and its main compounds can inhibit the toxicity of different toxins by the antioxidant, antiinflammatory, and anti-apoptotic properties as well as the modulation of Inhibitor of kappaB kinase (IKK), Extracellular signal-regulated protein kinase1/2 (ERK1/2), p38, inducible nitric oxide synthase, and nuclear factor-κB (NF-κB) signaling pathways. More high-quality investigations in both experimental and clinical studies need to firmly establish the efficacy of licorice and its main constituents against toxic agents.

Preparation and in vitro/in vivo evaluations of novel ocular micelle formulations of hesperetin with glycyrrhizin as a nanocarrier

The purpose of this study was to explore the potential of formulating hesperetin into an ophthalmic solution with dipotassium glycyrrhizinate (DG) as a micelle nanocarrier. A DG-based micelle ophthalmic solution encapsulating hesperetin (DG-Hes) was developed and its in vitro/in vivo characterizations were evaluated. The optimal formulation featured a DG/hesperetin (Hes) weight ratio of 12:1 and an encapsulation efficiency of 90.4 ± 1.7%; The optimized DG-Hes was characterized as small uniform spheres with an average micelle size of 70.93 ± 3.41 nm, a polydispersity index of 0.11 ± 0.02, and an electrically negative surface (-36.12 ± 2.79 mV). The DG-Hes ophthalmic solution had good tolerance in rabbit eyes. DG-Hes significantly improved the in vitro passive permeation, ex vivo corneal permeation, and in vivo ocular bioavailability of Hes. DG-Hes showed markedly increases in in vitro antioxidant activity. In vitro antibacterial activity tests revealed a lower minimum inhibitory concentration and lower minimum bactericidal concentration for DG-Hes ophthalmic solution were lower than for free Hes. DG-Hes ophthalmic solution also significantly reduced symptoms of eye infection in the rabbit bacterial keratitis model when compared to a Hes suspension. These results suggest that DG-Hes eye drops may be useful as a new ophthalmic preparation for the treatment of ocular diseases, especially bacterial ophthalmopathy.