The Inhibitory Effects Of Hesperidin On Hypermelanosis Of Guinea Pig Induced By UVB

BackgroundPeople, especially wowen desire to achieve a lighter skin color, buton the influence of age and environmental factors, our skin becomes dim.Some diseases like chloasma, post imflamatory pigmentation, seborrheickeratosis may bring some embarrassing in people's life. There are threemain reasons for it: (1) increased melanin in skin (2) decreasedcapillaries. Melanin is the most important factor.Melanin is the most important factor in determination of mammalianskin color and hair color. It is synthesized by melanocytes distribution inthe basal layer of the epidermis. As a result of the key role played bytyrosinase in melanin biosynthesis, most whitening agents can inhibit thisenzyme through several mechanisms: (1) interference with itstranscription and/or glycosylation; (2) inhibition by different modalities,(3) reduction of by-products; (4) post-transcriptional comtrol.Hydroquinone has been widely used to ease pigmentation since1961, because of its toxic effect, hydroquinone is gradually less used onclinic. New ingredients which are safe and effective on curing hyperpigmentation are extremely needed. The ideal depigment compoundshould have a potent, rapid and, permanent and selective bleaching effecton hyperactivated melanocytes, acting at one or more steps of thepigmentation process with no short or long-term side-effects,Flavonoids comprise a large group of naturally existed, lowmolecular weight, polyphenolic compounds widely distributed in theplant kingdom as secondary metabolites. They represent one of the mostimportant and interesting classes of biologically active compounds andexisit both in the free state and as glycosides.The inhibitiory action of glycyrrhizae extracts on mushroomtyrosinase has been confirmed. Ammonium glycyrrhizinate (18α-GL), arbutin and hydroquinone were investigated in vitro for the actionon tyrosinase activity, melanin content, and cell proliferation in culturedB16F10 murine melanoma cells. The results showed that all of themexhibited an inhibitory effect on tyrosinase activity and melaninproduction.Docter Yue in our department observed different concentration ofHesperidin and Glycyrrhizae's effects on melanin synthesis,and foundHesperidin and Glycyrrhizae can inhibit melanogenesis and the activityof tyrosinase activity, and are safer than hydroquinone.Hesperidin, a bioflavonoid, is an abundant and inexpensiveby-product of Citrus cultivation. No signs of toxicity have been observed with the normal intake of hesperidin or related compounds. Bothhesperidin and its aglycone hesperetin have been reported to possess awide range of pharmacological properties.ObjectiveTo investigate the inhibitory effects of hesperidin, Ammoniumglycyrrhizinate and extract of glycyrrhizae on hypermelanosis andprovide experimental evidence for treating skin disorders.MethodsTwo flavonoids with strong inhibitory effects on tyrosinase activitywere tested. The changes of melanocyte number and morphology andmelanin in epidermis were observed in the experimental hypermelanosismodel induced by UVB radiation on brownish guinea pig.ResultsMelanocytes and melanin granules were decreased with thetreatment of hesperidin, Ammonium glycyrrhizinate and extract ofglycyrrhizae.ConclusionThere are inhibitory effects on UVB induced hypermelanosis by using hesperidin, Ammonium glycyrrhizinate and extract ofglycyrrhizae.