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 92 Med & Health Jun 2019;14(1): 91-105 Hazirah H. et al. 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-dimethylthiazol2-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.

Optimized Internal Control and Gene Expression Analysis in Epstein-Barr Virus-Transformed Lymphoblastoid Cell Lines

The Epstein-Barr virus-transformed lymphoblastoid cell line (LCL) is one of the major genomic resources for human genetics and immunological studies. Use of LCLs is currently extended to pharmacogenetic studies to investigate variations in human gene expression as well as drug responses between individuals. We evaluated four common internal controls for gene expression analysis of selected hematopoietic transcriptional regulatory genes between B cells and LCLs. In this study, the expression pattern analyses showed that TBP (TATA box-binding protein) is a suitable internal control for normalization, whereas GAPDH (glyceraldehyde-3-phosphate dehydrogenase) is not a good internal control for gene expression analyses of hematopoiesis-related genes between B cells and LCLs at different subculture passages. Using the TBP normalizer, we found significant gene expression changes in selected hematopoietic transcriptional regulatory genes (downregulation of RUNX1 , RUNX3 , CBFB , TLE1, and NOTCH2; upregulation of MSC and PLAGL2) between B cells and LCLs at different passage numbers. These results suggest that these hematopoietic transcriptional regulatory genes are potential cellular targets of EBV infection, contributing to EBV-mediated B-cell transformation and LCL immortalization.

Expression changes of in human mitochondrial COX genes in human lymphocytes after exposed by 60Co γ-rays / 中华放射医学与防护杂志

Objective To explore the changes of human mitochondrial COX Ⅰ , COX Ⅱ and COX Ⅲ genes expression induced by ionizing irradiation. Methods Changes of human COX genes expression were detected by RT-PCR and Real-time PCR 8 h after the irradiation in human lymphoblastoid cell lines,which were exposed to 1-10 Gy60Co γ-rays. The protein levels were detected by flow cytometry and the COX activity was measured by colorimetry. The dose-effect relationships between the expression changes of the genes and the doses were established. The changes of these genes expression were also analyzed at different post-radiation time-points between 0. 5 h and 72 h after irradiation of 5 Gy in order to explore the time-effect. Results The expression of 3 genes at mRNA level was up-regulated. A good dose-effect relationship was showed for COXⅠ and COX Ⅲ at dose range of 0-3 Gy and 0-8 Gy for COX Ⅱ ( F COXⅠ=116. 62, FCOXⅡ = 17. 89, FCOXⅢ = 8.20, P ＜ 0. 05). For the time-effect after irradiation, the gene expression levels of COX Ⅱ and COX Ⅲ genes were up-regulated and the peak change occurred at 4 h after irradiation. For COX Ⅰ gene, the mRNA expression levels were down-regulated during 0.5-72 h( FCOXⅠ =31.99, FCOXⅡ = 19.47, FCOXⅢ = 20. 64, P ＜0. 05 ). At the protein level, the levels of COX Ⅰ and COX Ⅱ were lowered in lower doses and enhanced in higher doses, and the levels of COX Ⅲ were decreased at all dose levels (FCOX Ⅰ = 16.96, FCOXⅡ = 32.5, FCOXⅢ = 6. 51, P ＜ 0. 05 ). The protein levels of COX Ⅰ and COX Ⅱ were enhanced during 4-72 h and 8-72 h respectively after 5 Gy irradiation ( FCOX Ⅰ = 14.68,FCOXⅡ = 17. 18, FCOXⅢ =2. 52, P ＜0. 05). The activities of COX were lowered at different dose levels and different time-points. Conclusions Ionizing radiation might induce the changes in mitochondrial COX Ⅰ,COX Ⅱ and COX Ⅲ gene expression, and lead to the reduction of the COX activities.

Preliminary detection of expression changes of human mitochondrial COXI,ND1 and ND6 gene induced by 60Co γ-rays / 中华放射医学与防护杂志

Objective To explore the changes of human mitochondrial COXI,ND1 and ND6 genes expression induced by ionizing irradiation.Methods Changes of human COXI,ND1 and ND6 gene expression were detected by RT-PCR and Real-time PCR 8 h after the irradiation in human lymphoblastoid cell lines,which were exposed to 1-10 Gy 60Co γ-rays.And the dose-effect relationships between expression changes of the genes and the doses were analyzed.The changes of these three genes expression were also analyzed at different post-radiation time-points between 0.5 h and 72 h after irradiation of 5 Gy in order to explore the time-effect.Results The expression of three genes COXI,ND1 and ND6,showed either the dose-effect or the time-effect after irradiation.The gene expression levels of three genes up-regulated generally and the peak change time-point was 4 h after irradiation.Conclusion Ionizing radiation,msht induce the changes of mitochondrial gene expression,and the gene expression level is up-regulated.

Establishment of a Human Lymphoblastoid Cell Line from Human Lymph Node / 昆明医科大学学报

A human lymphoblastoid cell line named KGHLY, which has been established from a human lymph node, is reported in this paper. KGHLY grew in suspension and formed clamps easily. It grew rapidly and the population doubling time of the 30th generation cells was 26 hours. Under the light and electron microscope the culture cells were similar to lymphoblastoid cells in morphology and structure. The cells secreted IgM. Surface marker studies showed that there were no receptors for sheep erythrocytes. The results suggested that the cells derived from B lymphocytes. The karyotype was aneuploid with a modal chromosome number of 44—46. It has lasted for over one year through seventy passages. The cells stored in liquid nitrogen and their revival was fine. This cell line will be available material for the study of lymphoblastoid cells and human-human hybridoma.