hanani razali

Background: Synthesis of thyroid hormones and regulation of their metabolism involve free radicals that may affect redox balance in the body. Thyroid disorders causing variations in the levels of thyroid hormones may alter cellular oxidative stress. The aim of this study was to measure the antioxidant activities and biomarkers of oxidative stress in serum and red blood cells (RBC) of patients with benign and malignant thyroid disorders and to investigate if changes in the antioxidant activities in these patients were linked to alterations in genes encoding the antioxidant enzymes. Methods: Forty-one patients with thyroid disorders from University of Malaya Medical Centre were recruited. They were categorised into four groups: multinodular goitre (MNG) (n = 18), follicular thyroid adenoma (FTA) (n = 7), papillary thyroid cancer (PTC) (n = 10), and follicular thyroid cancer (FTC) (n = 6). Serum and RBC of patients were analysed for antioxidant activities, antioxidant enzymes, and biomarkers of oxidative stress. Alterations in genes encoding the antioxidant enzymes were analysed using whole exome sequencing and PCR–DNA sequencing. Results: Patients with thyroid disorders had significantly higher serum superoxide dismutase (SOD) and catalase (CAT) activities compared to control, but had lower activities in RBC. There were no significant changes in serum glutathione peroxidase (GPx) activity. Meanwhile, GPx activity in RBC was reduced in PTC and FTC, compared to control and the respective benign groups. Antioxidant activities in serum were decreased in the thyroid disorder groups when compared to the control group. The levels of malondialdehyde (MDA) were elevated in the serum of FTA group when compared to controls, while in the RBC, only the MNG and PTC groups showed higher MDA equivalents than control. Serum reactive oxygen species (ROS) levels in PTC group of both serum and RBC were significantly higher than control group. Whole exome sequencing has resulted in identification of 49 single nucleotide polymorphisms (SNPs) in MNG and PTC patients and their genotypic and allelic frequencies were calculated. Analyses of the relationship between

Carrageenan is a polysaccharide extracted from different species of red seaweed for use in pharmaceuticals and cosmetics industries. In Malaysia, κ-carrageenan is obtained through extraction from the tropical red seaweed Kappaphycus alvarezii. The use of tissue culture techniques in the propagation of K. alvarezii has proven to be effective in solving cultivation problems and produced high-quality seedlings and providing a sustainable source of better quality car-rageenan. In order to understand the molecular mechanisms behind that, a proteomic investigation was conducted comparing the changes in protein expression in tissue-cultured and liquid-cultured K. alvarezii after 60 days of cultivation. Proteomic analysis was used to study the changes in the protein expression level between liquid-cultured and tissue-cultured of the red seaweed K. alvarezii. A total of 45 protein spots were found to be significantly different in their densities and three proteins, namely β-amylase, NAD-dependent sugar epimerase and B-phycoerythrin, showed a consistent pattern of upregulation in ELISA analyses, hence validating the 2-DE profiles. Changes in the proteins expression level were noticed in proteins related to energy production, metabolism and cellular maintenance. The protein changes in tissue-cultured seaweed possibly play an essential role in the production of carrageenan.

Background. Barringtonia racemosa is a medicinal plant belonging to the Lecythidaceae family. The water extract of B. racemosa leaf (BLE) has been shown to be rich in polyphenols. Despite the diverse medicinal properties of B. racemosa, information on its major biological effects and the underlying molecular mechanisms are still lacking. Methods. In this study, the effect of the antioxidant-rich BLE on gene expression in HepG2 cells was investigated using microarray analysis in order to shed more light on the molecular mechanism associated with the medicinal properties of the plant. Results. Microarray analysis showed that a total of 138 genes were significantly altered in response to BLE treatment (p < 0.05) with a fold change difference of at least 1.5. SERPINE1 was the most significantly up-regulated gene at 2.8-fold while HAMP was the most significantly down-regulated gene at 6.5-fold. Ingenuity Pathways Analysis (IPA) revealed that ''Cancer, cell death and survival, cellular movement'' was the top network affected by the BLE with a score of 44. The top five canonical pathways associated with BLE were Methylglyoxal Degradation III followed by VDR/RXR activation, TR/RXR activation, PXR/RXR activation and gluconeogenesis. The expression of genes that encode for enzymes involved in methylglyoxal degradation (ADH4, AKR1B10 and AKR1C2) and glycolytic process (ENO3, ALDOC and SLC2A1) was significantly regulated. Owing to the Warburg effect, aerobic glycolysis in cancer cells may increase the level of methylglyoxal, a cytotoxic compound. Conclusions. BLE has the potential to be developed into a novel chemopreventive agent provided that the cytotoxic effects related to methylglyoxal accumulation are minimized in normal cells that rely on aerobic glycolysis for energy supply.

Abstract
Background: Tamarindus indica L. (T. indica) or locally known as “asam jawa” belongs to the family Leguminosae. T.
indica seeds as by-products from the fruits were previously reported to contain high polyphenolic content. However,
identification of their bioactive polyphenols using recent technologies is less well researched but nonetheless
important. Hence, it was the aim of this study to provide further information on the polyphenolic content and
antioxidant activities as well as to identify and quantify its bioactive polyphenols.
Methods: T. indica seeds were extracted with methanol and were then fractionated with different compositions of
hexane, ethyl acetate and methanol. Polyphenolic contents were measured using Folin-Ciocalteu assay while
antioxidant activities were measured using DPPH radical scavenging and ferric reducing (FRAP) activities. The cytotoxic
activities of the crude extract and the active fraction were evaluated in HepG2 cells using MTT assay. The cells were
then pre-treated with the IC20 concentrations and induced with H2O2 before measuring their cellular antioxidant
activities including FRAP, DPPH, lipid peroxidation, ROS generation and antioxidant enzymes, SOD, GPx and CAT.
Analyses of polyphenols in the crude extract and its active fraction were done using UHPLC and NMR.
Results: Amongst the 7 isolated fractions, fraction F3 showed the highest polyphenolic content and antioxidant
activities. When HepG2 cells were treated with fraction F3 or the crude extract, the former demonstrated higher
antioxidant activities. F3 also showed stronger inhibition of lipid peroxidation and ROS generation, and enhanced
activities of SOD, GPx and CAT of HepG2 cells following H2O2-induced oxidative damage. UHPLC analyses revealed the
presence of catechin, procyanidin B2, caffeic acid, ferulic acid, chloramphenicol, myricetin, morin, quercetin, apigenin
and kaempferol, in the crude seed extract of T. indica. UHPLC and NMR analyses identified the presence of caffeic acid
in fraction F3. Our studies were the first to report caffeic acid as the active polyphenol isolated from T. indica seeds
which likely contributed to the potent antioxidant defense system of HepG2 cells.
Conclusion: Results from this study indicate that caffeic acid together with other polyphenols in T. indica seeds can
enhance the antioxidant activities of treated HepG2 cells which can provide protection against oxidative damage.

In this study, the effects of low and high concentrations of the Anacardium occidentale shoot extracts on gene expression in liver HepG2 cells were investigated. From MTT assays, the concentration of the shoot extracts that maintained 50% cell viability (IC50) was 1.7 mg/ml. Cell viability was kept above 90% at both 0.4 mg/ml and 0.6 mg/ml of the extracts. The three concentrations were subsequently used for the gene expression analysis using Affymetrix Human Genome 1.0 S.T arrays. The microarray data were validated using real-time qRT–PCR. A total of 246, 696 and 4503 genes were significantly regulated (P < 0.01) by at least 1.5-fold in response to 0.4, 0.6 and 1.7 mg/ml of the extracts, respectively. Mutually regulated genes in response to the three concentrations included CDKN3, LOC100289612, DHFR, VRK1, CDC6, AURKB and GABRE. Genes like CYP24A1, BRCA1, AURKA, CDC2, CDK2, CDK4 and INSR were significantly regulated at 0.6 mg/ml and 1.7 mg but not at 0.4 mg/ml. However, the expression of genes including LGR5, IGFBP3, RB1, IDE, LDLR, MTTP, APOB, MTIX, SOD2 and SOD3 were exclusively regulated at the IC50 concentration. In conclusion, low concentrations of the extracts were able to significantly regulate a sizable number of genes. The type of genes that were expressed was highly dependent on the concentration of the extracts used.

Tamarindus indica L. (T. indica) or locally known as asam jawa belongs to the family of Leguminosae. The fruit pulp had been reported to have antioxidant activities and possess hypolipidaemic effects. In this study, we attempted to investigate the gene expression patterns in human hepatoma HepG2 cell line in response to treatment with low concentration of the fruit pulp extracts. Microarray analysis using Affymetrix Human Genome 1.0 S.T arrays was used in the study. Microarray data were validated using semi-quantitative RT–PCR and real-time RT–PCR. Amongst the significantly up-regulated genes were those that code for the metallothioneins (MT1M, MT1F, MT1X) and glutathione S-transferases (GSTA1, GSTA2, GST02) that are involved in stress response. APOA4, APOA5, ABCG5 and MTTP genes were also significantly regulated that could be linked to hypolipidaemic activities of the T. indica fruit pulp.

The total phenolic content and antioxidant activities of methanol, hexane and ethyl acetate extracts of the shoots of Anacardium occidentale were measured. Total phenolic content was assessed by the Folin–Ciocalteau assay whereas antioxidant activities were assessed by measuring the ability of the extracts to scavenge the ABTS·+ and DPPH· radicals, superoxide anion radicals and nitric oxide radicals as well as their ability to reduce ferric ions. Results indicated that the methanol extract of A. occidentale was the most potent reducing agent and radical-scavengers compared to the other two extracts. The ethyl acetate extract exhibited some antioxidant activities whereas the hexane extract is the least reactive. The order of the antioxidant potency of the plant extract is methanol > ethyl acetate > hexane. The methanol extract contained more than 7 fold of total phenolic content compared to the hexane and ethyl acetate extracts indicating the likely possibility that the observed antioxidant activities were partly contributed by the phenolics. The results suggest that the shoots of A. occidentale are a source of natural antioxidants.

Numerous studies have revealed the ability of phenolic antioxidants to intercept the oxidative damage caused by free radicals. Phenolics contain various biological activities including antioxidant, anti-inflammatory, anti-diabetic and anti-cancer activities. Tamarindus indica L. (T. indica) or locally known as asam jawa, belongs to the family Leguminosae. Our group had earlier shown that the methanol extracts of the T. indica seeds (TISM) have high radical scavenging activity and phenolic content. Studies have also shown that the seed extracts of T. indica had antihyperglycaemic and hypolipidaemic effects in streptozotocin-induced diabetic rats. However, scientific data on the molecular mechanisms underlying the beneficial properties of the TISM are still lacking. In this study, we investigated the effects of the extracts on the expression of genes in cultured HepG2 cells using microarray technology. A non-toxic dose of the TISM was used for the gene expression analysis. The microarray analysis was performed on Affymetrix Human Genome 1.0 S.T arrays. Data generated were pre-analysed using the NetAffx Analysis Centre before further analysed using the Partek Genomics Suite software. Analysis of variance (ANOVA) was applied to determine differentially expressed sets of genes. P value less than 0.05 was considered statistically significant. Filtering criterion was set as a fold change ≥ 1.5. Verification of the microarray data was performed using quantitative RT-PCR. A total of 284 genes were up regulated and 78 genes were down-regulated. Amongst the significantly regulated genes were associated with antioxidant activity, insulin signaling and anti-obesity. These results indicate the potential of the TISM to act as antioxidants and antihyperglycaemic agents.

The presence of phenolic antioxidants in plants has led to the exploration for their potential use as food supplements and in disease prevention. Phenolics exert various biological activities including antioxidant, anti-inflammatory and anti-cancer activities. Tamarindus indica L. (T. indica) or locally known as asam jawa, belongs to the family Leguminosae. Our group had earlier shown that the methanol extracts of the T. indica leaf (TILM) have the highest antioxidant activities and phenolic content compared to the other parts of the plant. In this study, we investigated the effects of TILM on the antioxidant levels and indices of oxidative damages using human liver cell line (HepG2). TILM showed high ferric reducing (FRAP) and DPPH radical scavenging activities in treated HepG2 cells. The extract was found to significantly increase the antioxidant enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) as well as significantly inhibited H2O2-induced lipid peroxidation in treated HepG2 cells. The extract could have exerted its antioxidant effects via regulating the removal of ROS which was observed through the measurement of dichlorofluorescein (DCF) fluorescence in the treated cells. Reversed-phase HPLC analyses of TILM revealed the presence of phenolic compounds including catechin and epicatechin which could have contributed towards the observed biological activities. The increase in antioxidant activities was accompanied by increased expression of genes that are associated with antioxidant activity and stress response. Results from this study indicate that TILM can enhance the antioxidant activities of treated HepG2 cells which can provide protection against oxidative damage.