Antioxidant properties of stingless bee honey and its effect on the viability of lymphoblastoid cell line

Research on the medical benefit of stingless bee honey (kelulut honey) is rather new although it has been used as traditional food and additive for ages. The primary objective of our study was to evaluate the antioxidant properties of kelulut honey and its effect on lymphoblastoid cell line. We analysed the antioxidant properties of kelulut honey by ferric reducing antioxidant potential assay, total phenolic and flavonoid contents using UV spectrophotometry. The total phenolic content, total flavonoid content and ferric reducing antioxidant potential of Malaysian kelulut honey produced by Trigona spp. were found to be 844.45 mg RE/kg honey, 78.29 mg RE/kg honey and 1132.66 mM FE/kg honey, respectively. Our findings showed a strong correlation between total phenolics and flavanoids contents with its antioxidant potential at R2 = 0.920 and R2 = 0.951, respectively. The effect of honey on cell viability of lymphoblastoid cell line (LCL) was also investigated. The cells were cultured in RPMI-1640 medium supplemented with 0 - 500 μg/mL of kelulut honey for 24 hours. Cell viability was quantitated using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, MTS assay showed that honey supplementation boosted the viability of LCL up to 164.64% (p< 0.01). The significant increase in cell viability might be modulated by the antioxidant properties of kelulut honey

Ginger extract (Zingiber officinale Roscoe) triggers apoptosis in hepatocarcinogenesis induced rats

Ginger extract has been reported previously by our group to exhibit anticancer and an-tioxidant effects by reducing tumour burden and lipid peroxidation respectively in he-patocarcinogenesis induced rats. The current study examined the expression of pro-apoptotic protein caspase-8 and anti-apoptotic protein Bcl-2 in hepatocarcinogenesis treated rats. Thirty normal male Wistar rats were divided into 5 groups based on the diet given: i) control (normal rat chow), ii) olive oil, iii) ginger extract (100mg/kg body weight), iv) choline deficient diet + ethionine, CDE (to induce liver cancer) and v) CDE+ ginger extract. Rats were killed at week 8, and liver tissues were excised for immuno-histochemical study to identify pro-apoptotic and anti-apoptotic proteins, caspase-8 and Bcl-2. The observation on H&E staining confirmed the CDE diet induced liver can-cer as indicated by the presence of numerous oval cells. Identification of Bcl-2 expres-sion showed that 91.6% (11/12) of the samples from the CDE group revealed positive staining while treatment with ginger extract however inhibited the expression with only 8.4% (1/12) samples showing positive staining for Bcl-2. As for caspase-8 protein, 41.7% (5/12) of the samples from CDE group showed positive staining, which in-creased to 100% (12/12) with ginger extract treatment. Our findings suggest that gin-ger extract has an anticancer effect by inducing apoptosis in liver cancer cells via up-regulation of the expression of pro-apoptotic protein, caspase-8 and down-regulation of the expression of anti-apoptotic protein Bcl-

Honey: food or medicine?

Honey is a natural substance produced by honeybees, Apis mellifera, from the nectar of blossomed flowers or exudates of trees and plants producing nectar honeys or honeydews, respectively. It is a supersaturated solution of sugars, enriched with proteins, minerals, vitamins, organic acids and polyphenols. Honey possesses numerous nutritional, healing and prophylactic properties attributed by the rich components found in honey. Some of the health beneficial properties include wound healing, antimicrobial, antioxidant and anti-inflammatory potential. This review relates the nutritional composition, antioxidant and therapeutical effects of honey with emphasis on Malaysian honeys

Melanogenesis inhibition by palm tocotrienol rich fraction in cellular ageing

Melanin is the pigment that determines skin color. Melanin synthesis is catalysed by the enzyme tyrosinase and is controlled by TYR, TYRP1 and TYRP2 genes. In this study, tocotrienol rich fraction (TRF) was used to inhibit melanin synthesis. TRF contains 75% α-tocotrienol and 25% tocopherol. The objective of this study was to determine the effect of tocotrienol rich fraction (TRF) on melanin synthesis by determining melanin content and expression of genes involved in the regulation of melanin synthesis in skin melanocytes. Melanin synthesis was studied by determining melanin level and tyrosinase enzyme activity, while expression of TYR, TYRP1 and TYRP2 genes was determined by quantitative real time reverse transcriptase poly-merase chain reaction (real time RT-PCR). Primary culture of skin melanocytes were divided into two groups; control and cells that were treated with 500 μg/ml tocotrienol rich fraction for 24 hours. Our results showed that there was a reduction in melanin content and tyrosinase activity in skin melanocytes treated with tocotrienol rich fraction compared to the control (p<0.05). Expression of TYRP2 gene in melanocytes treated with tocotrienol rich fraction was also decreased (p<0.05) compared to the control. In conclusion, palm tocotrienol rich fraction has anti pigmentation property that inhibits melanin synthesis in cellular aging by inhibiting tyrosinase activity and down regulating TYRP2 gene expression

Does chlorella vulgaris modulate the expression of COL and MMP Genes in skin ageing?

Chlorella vulgaris, a unicellular microalgae, produces many intracellular phytochemicals namely carotenoids, tocopherols, ubiquinone and protein. Skin ageing which is induced by oxidative stress involves decreased extracellular matrix synthesis and increased expression of enzymes that degrade the collagenous matrix. The objective of this study was to determine the effect of C. vulgaris on the expression of genes encoded for collagen (COL) and matrix metalloproteinases (MMPs) which are involved in skin ageing. Human diploid fibroblasts (HDFs) were obtained from circumcision foreskin of 8-12 year-old boys. HDFs were cultured into 3 groups: untreated control cells, cells with stress-induced premature senescence (SIPS; cells were induced with H2O2 at passage 6 for 2 weeks) and SIPS treated with C. vulgaris (prolonged C. vulgaris treatment started at passage 4 and combined treatment with H2O2 at passage 6 for 2 weeks). Senescence-associated ß-galactosidase (SA ß-gal) was determined using senescent cells histochemical staining kit (Sigma, USA). Expression of COLI, COLIII, COLIV, MMPI, MMPII and MMPIII genes was quantitatively analysed with real-time RT-PCR method (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDFs treated with H2O2 (SIPS) exhibited senescent morphological features of flattening and enlarged with increased expression of SA ß-gal (p<0.05). Gene expression analysis showed COLI was downregulated in SIPS and SIPS treated with C. vulgaris (p<0.05) while COLIII decreased in SIPS and increased in SIPS treated with C. vulgaris (p<0.05). Expression of MMPI was increased in SIPS and SIPS treated with C. vulgaris (p<0.05) indicating its synergistic effect with H2O2 treatment. In conclusion, in skin ageing, COLI and COLIII genes were downregulated while MMPI was upregulated. C. vulgaris modulated the expression of COL and MMP genes by downregulating COLI and upregulating COLIII and MMPI but it did not exert anti-ageing effect