Investigation of genotoxic effects of rhododendron honey using three mammalian bioassays in vivo

Abstract

Rhododendron honey (RH) is obtained from the rhododendron plants are grown in many regions around the world, causes poisoning in humans due to the grayanotoxin (GTX) compound in its structure. It is used by the public as a therapeutic for some diseases. It was aimed to study the genotoxic and cytotoxic effects of RH in mouse bone-marrow and sperm cells by using three mammalian bioassays. 25, 50 and 75 mg kg⁻¹ concentrations of RH given to male mice via gavage for 24 and 48 h treatment periods and its active ingredient Grayanatoxin (GTX-III) 0.01 mg kg⁻¹ by i.p. injection. Chromosome aberrations (CA), polychromatic erythrocytes (PCE)/normochromatic erythrocytes (NCE), micronucleated polychromatic erythrocytes (MNPCE) and sperm abnormalities were investigated. The results demonstrated that all the tested concentrations of RH significantly induced total abnormal cell frequency including chromosomal breaks for two time periods. In the MN assay, 75 mg kg⁻¹ RH and 0.01 mg kg⁻¹ GTX-III significantly increased % MNPCE and significantly reduced PCE/NCE ratios after 24 and 48 h treatments on mice demonstrating potential genotoxic and cytotoxic effect. Although there was a concentration-related increase in the percentage of total sperm abnormalities, this increase was not statistically significant compared to control. As a result, microscopic genotoxicity and cytotoxicity marker tests showed that RH and its active ingredient GTX-III have potential genotoxic and cytotoxic effect on mice bone marrow cells. It is understood that RH that is used to treat some diseases by public, should be handled carefully and used in a controlled manner.

Highlights

• Chromosome aberration, micronucleus and sperm morphology assays are recommended as reliable biological indicators.

• RH and its active ingredient GTX-III have potential genotoxic and cytotoxic effect on mice bone marrow cells.

• Significant changes were observed upon the treatment of 75 mg kg⁻¹ MH for MN assay.

Keywords:

• Mad honey
• grayanatoxin
• chromosomal aberration
• micronucleus formation
• sperm abnormality

Disclosure statement

The authors declare that there is no conflict of interest.

Additional information

Funding

This study was supported by Duzce University Scientific Research Fund [Project Number= 2013.01.01.199].