Structure-activity relationship of flavanone. Anti-degranulation activity of 7-O-substituted hesperetin

Hesperetin's health potential: moving from preclinical to clinical evidence and bioavailability issues, to upcoming strategies to overcome current limitations

Flavonoids are common in the plant kingdom and many of them have shown a wide spectrum of bioactive properties. Hesperetin (Hst), the aglycone form of hesperidin, is a great example, and is the most abundant flavonoid found in Citrus plants. This review aims to provide an overview on the in vitro, in vivo and clinical studies reporting the Hst pharmacological effects and to discuss the bioavailability-related issues. Preclinical studies have shown promising effects on cancer, cardiovascular diseases, carbohydrate dysregulation, bone health, and other pathologies. Clinical studies have supported the Hst promissory effects as cardioprotective and neuroprotective agent. However, further well-designed clinical trials are needed to address the other Hst effects observed in preclinical trials, as well as to a more in-depth understanding of its safety profile.

Structure-activity relationships of flavanones, flavanone glycosides, and flavones in anti-degranulation activity in rat basophilic leukemia RBL-2H3 cells

The incidence of type I allergies, which are associated with mast cell degranulation and local inflammation, is increasing, and new treatments are needed. To date, structure-activity relationships of flavonoids in their degranulation-inhibiting activity have not been systematically characterized. In the current study, the degranulation-inhibiting activity of a series of flavonoids was evaluated. The following three observations were made: (1) the activity disappears when a sugar moiety is introduced into the A ring of the flavanone; (2) the activity depends on the number of hydroxyl groups on the B ring; (3) the activity is markedly enhanced when a double bond is introduced into the C ring. The information obtained in the current study may guide the development of a therapy for type I allergies.