title: Gelam honey protects against gamma-irradiation damage to antioxidant enzymes in human diploid fibroblasts.
abstract: The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were studied: untreated control, irradiated HDFs, Gelam honey-treated HDFs and HDF treated with Gelam honey pre-, during- and post-irradiation. HDFs were treated with 6 mg/mL of sterilized Gelam honey (w/v) for 24 h and exposed to 1 Gray (Gy) of gamma rays at the dose rate of 0.25 Gy/min. Gamma-irradiation was shown to down-regulate SOD1, SOD2, CAT and GPx1 gene expressions (p < 0.05). Conversely, HDFs treated with Gelam honey alone showed  up-regulation of all genes studied. Similarly, SOD, CAT and GPx enzyme activities in HDFs decreased with gamma-irradiation and increased when cells were treated with Gelam honey (p < 0.05). Furthermore, of the three different stages of study treatment, pre-treatment with Gelam honey caused up-regulation of SOD1, SOD2 and CAT genes expression and increased the activity of SOD and CAT. As a conclusion, Gelam honey modulates the expression of antioxidant enzymes at gene and protein levels in irradiated HDFs indicating its potential as a radioprotectant agent.
authors: Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia.
authors: Tengku Ahbrizal Farizal Tengku
authors: TA
authors: Ahmad
authors: Zakiah
authors: Z
authors: Jubri
authors: Nor Fadilah
authors: NF
authors: Rajab
authors: Khairuddin Abdul
authors: KA
authors: Rahim
authors: Yasmin Anum Mohd
authors: YA
authors: Yusof
authors: Suzana
authors: S
authors: Makpol
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D002648:Child; D004171:Diploidy; D005347:Fibroblasts / Q000187:drug effects* / Q000201:enzymology* / Q000528:radiation effects; D005720:Gamma Rays; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000528:radiation effects; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D006722:Honey; D006801:Humans; D008297:Male; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism
chemical_list: D000975:Antioxidants; D011837:Radiation-Protective Agents; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase