|Jmol-3D images||Image 1|
|Molar mass||270.24 g mol−1|
|Appearance||Yellow crystalline solid|
|Melting point||345 to 350 °C (653 to 662 °F; 618 to 623 K)|
|λmax||267, 296sh, 336 nm in methanol|
|Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)|
Apigenin (4’,5,7-trihydroxyflavone), found in many plants, is a natural product belonging to the flavone class that is the aglycone of several naturally occurring glycosides. It is a yellow crystalline solid that has been used to dye wool.
In in vitro experiments and animal studies, a variety of potential biological activities of apigenin have been identified, but its effects on human health are unknown.
Apigenin induces autophagy (a kind of cellular waste-recycling system) in leukemia cells, which may support a possible chemopreventive role, but that induction of autophagy simultaneously induces resistance against the chemotherapy drug vincristine. Apigenin is a potent inhibitor of CYP2C9, an enzyme responsible for the metabolism of many pharmaceutical drugs in the body.
Apigenin has been shown to prevent renal damage caused by cyclosporin in rats, associated with reduced expression of the cell death mediator bcl-2 in histopathological sections. Cyclosporine A enhances the expression of transforming growth factor-β in the rat kidney, which signifies accelerated apoptosis. Therefore, transforming growth factor-β and apoptotic index may be used to assess apigenin and its effect on cyclosporine A-induced renal damage.
Apigenin acts as a monoamine transporter activator, one of the few chemicals demonstrated to possess this property. Apigenin is a ligand for central benzodiazepine receptors that competitively inhibited the binding of flunitrazepam with a Ki of 4μM, exerting anxiolytic and slight sedative effects. Apigenin shows second-order positive modulatory activity at GABAA receptors. It has also effects on adenosine receptors and NMDA receptors.
Apigenin may also stimulate adult neurogenesis, with at least one study claiming that apigenin "stimulate[s] adult neurogenesis in vivo and in vitro, by promoting neuronal differentiation" and may be useful "for stimulating adult neurogenesis and for the treatment of neurological diseases, disorders and injuries, by stimulating the generation of neuronal cells in the adult brain." While potentially promising, the study used rats and its effects have yet to be demonstrated in humans.
Sources in nature
The naturally occurring glycosides formed by the combination of apigenin with sugars include:
- Apiin (apigenin 7-O-apioglucoside), isolated from parsley and celery
- Apigetrin (apigenin 7-glucoside), found in dandelion coffee
- Vitexin (apigenin 8-C-glucoside)
- Isovitexin (apigenin 6-C-glucosid)
- Rhoifolin (apigenin 7-O-neohesperidoside)
- Schaftoside (apigenin 6-C-glucoside 8-C-arabinoside)
- Merck Index, 11th Edition, 763.
- The Systematic Identification of Flavonoids. Mabry et al, 1970, page 81
- RR Ruela-de-Sousa, GM Fuhler, N Blom, CV Ferreira, H Aoyama, MP Peppelenbosch (2010). "Cytotoxicity of apigenin on leukemia cell lines: implications for prevention and therapy". Cell Death and Disease 1 (e19): 1–11.
- Si Dayong, Wang Y, Zhou Y-H, Guo Y, Wang J, Zhou H, Li Z-S, Fawcett JP (March 2009). "Mechanism of CYP2C9 inhibition by flavones and flavonols". Drug Metabolism and Disposition 37 (3): 629–634.
- Srikumar Chakravarthi, Chong Fu Wen, HS Nagaraja (2009). "Apoptosis and expression of bcl-2 in cyclosporin induced renal damage and its reversal by beneficial effects of 4,5,7 - Trihydroxyflavone". Journal of Analytical Bio Science 32 (4): 320–327.
- Chong FW, Srikumar Chakravarthi, HS Nagaraja, PM Thanikachalam, Nagarajah Lee (2009). "Expression of Transforming Growth factor-β and determination of Apoptotic Index in histopathological sections for assessment of the effects of Apigenin (4',5',7'- trihydroxyflavone) on Cyclosporine A induced renal damage". Malaysian Journal of Pathology 31 (1): 35–43.
- Zhao, G; Qin, GW; Wang, J; Chu, WJ; Guo, LH (2010). "Functional activation of monoamine transporters by luteolin and apigenin isolated from the fruit of Perilla frutescens (L.) Britt". Neurochemistry international 56 (1): 168–76.
- Viola, H; Wasowski, C; Levi De Stein, M; Wolfman, C; Silveira, R; Dajas, F; Medina, JH; Paladini, AC (1995). "Apigenin, a component of Matricaria recutita flowers, is a central benzodiazepine receptors-ligand with anxiolytic effects". Planta medica 61 (3): 213–6.
- Campbell EL, Chebib M, Johnston GAR (2004): "The dietary flavonoids apigenin and (−)-epigallocatechin gallate enhance the positive modulation by diazepam of the activation by GABA of recombinant GABAA receptors", Biochemical Pharmacology, Vol. 68, 1631
- Jacobson KA et al. (2002): "Interactions of flavones and other phytochemicals with adenosine receptors.", Adv. Exp. Med. Biol., Vol. 505, 163
- Losi G et al. (2004): "Apigenin modulates GABAergic and glutamatergic transmission in cultured cortical neurons." Eur. J. Pharmacol., Vol. 502, 41
- Zbidah, M; Lupescu, A; Jilani, K; Fajol, A; Michael, D; Qadri, SM; Lang, F (2012). "Apigenin-induced suicidal erythrocyte death". Journal of Agricultural and Food Chemistry 60 (1): 533–8.
- Taupin, P (2009). "Apigenin and related compounds stimulate adult neurogenesis. Mars, Inc., the Salk Institute for Biological Studies: WO2008147483". Expert opinion on therapeutic patents 19 (4): 523–7.
- The compound in the Mediterranean diet that makes cancer cells 'mortal' Emily Caldwell, Medical Express, May 20, 2013.
- Meyer, Hellen; Bolarinwa, Adrian; Wolfram, Guenther; Linseisen, Jakob (2006). "Bioavailability of Apigenin from Apiin-Rich Parsley in Humans". Annals of Nutrition and Metabolism 50 (3): 167–72.