Wan Zurinah Wan Ngah

Ginger Extract (Zingiber Officinale) has Anti-Cancer and Anti-Inflammatory Effects on Ethionine-Induced Hepatoma Rats

OBJECTIVE To evaluate the effect of ginger extract on the expression of NFκB and TNF-α in liver cancer-induced rats. METHODS Male Wistar rats were randomly divided into 5 groups based on diet: i) control (given normal rat chow), ii) olive oil, iii) ginger extract (100mg/kg body weight), iv) choline-deficient diet + 0.1% ethionine to induce liver cancer and v) choline-deficient diet + ginger extract (100mg/kg body weight). Tissue samples obtained at eight weeks were fixed with formalin and embedded in paraffin wax, followed by immunohistochemistry staining for NFκB and TNF-α. RESULTS The expression of NFκB was detected in the choline-deficient diet group, with 88.3 ± 1.83% of samples showing positive staining, while in the choline-deficient diet supplemented with ginger group, the expression of NFκB was significantly reduced, to 32.35 ± 1.34% (p<0.05). In the choline-deficient diet group, 83.3 ± 4.52% of samples showed positive staining of TNF-α, which was significantly reduced to 7.94 ± 1.32% (p<0.05) when treated with ginger. There was a significant correlation demonstrated between NFκB and TNF-α in the choline-deficient diet group but not in the choline-deficient diet treated with ginger extract group. CONCLUSION In conclusion, ginger extract significantly reduced the elevated expression of NFκB and TNF-α in rats with liver cancer. Ginger may act as an anti-cancer and anti-inflammatory agent by inactivating NFκB through the suppression of the pro-inflammatory TNF-α.

Effect of tocotrienols on hepatocarcinogenesis induced by 2-acetylaminofluorene in rats.

The effects of tocotrienols on hepatocarcinogenesis in rats fed with 2-acetylaminofluorene (AAF) were followed morphologically and histologically for a period of 20 wk. No differences between treated and control rats in the morphology and histology of their livers was observed. Cell damage was extensive in the livers of AAF-treated rats but less extensive in the AAF-tocotrienols-treated rats when compared with normal and tocotrienols-treated rats. 2-Acetylaminofluorene significantly increases the activities of both plasma and liver microsomal gamma-glutamyltranspeptidase (GGT) and liver microsomal UDP-glucuronyltransferase (UDP-GT). Tocotrienols administered together with AAF significantly decrease the activities of plasma GGT after 12 and 20 wk (P less than 0.01, P less than 0.002, respectively) and liver microsomal UDP-GT after 20 wk (P less than 0.02) when compared with the controls and with rats treated only with tocotrienols. Liver microsomal GGT also showed a similar pattern to liver microsomal UDP-GT but the decrease was not significant. These results suggest that tocotrienols administered to AAF-treated rats reduce the severity of hepatocarcinogenesis.

Comparative effects of α-tocopherol and γ-tocotrienol against hydrogen peroxide induced apoptosis on primary-cultured astrocytes

Oxidative stress is thought to be one of the factors that cause neurodegeneration and that this can be inhibited by antioxidants. Since astrocytes support the survival of central nervous system (CNS) neurons, we compared the effect of alpha-tocopherol and gamma-tocotrienol in minimizing the cytotoxic damage induced by H(2)O(2), a pro-oxidant. Primary astrocyte cultures were pretreated with either alpha-tocopherol or gamma-tocotrienol for 1 h before incubation with 100 microM H(2)O(2) for 24 h. Cell viability was then assessed using the MTS assay while apoptosis was determined using a commercial ELISA kit as well as by fluorescent staining of live and apoptotic cells. The uptake of alpha-tocopherol and gamma-tocotrienol by astrocytes were also determined using HPLC. Results showed that gamma-tocotrienol is toxic at concentrations >200 microM but protects against H(2)O(2) induced cell loss and apoptosis in a dose dependent manner up to 100 microM. alpha-Tocopherol was not cytotoxic in the concentration range tested (up to 750 microM), reduced apoptosis to the same degree as that of gamma-tocotrienol but was less effective in maintaining the viable cell number. Since the uptake of alpha-tocopherol and gamma-tocotrienol by astrocytes is similar, this may reflect the roles of these 2 vitamin E subfamilies in inhibiting apoptosis and stimulating proliferation in astrocytes.

Comparative effects of palm vitamin E and α-tocopherol on healing and wound tissue antioxidant enzyme levels in diabetic rats

The effect of supplementing 200 mg/kg body weight palm vitamin E (PVE) and 200 mg/kg body weight α-tocopherol (α-loc) on the healing of wounds in streptozotocin-induced diabetic rats was evaluated. The antioxidant potencies of these two preparations of vitamin E were also evaluated by determining the antioxidant enzyme activities, namely, glutathione peroxidase (GPx) and superoxide dismutase (SOD), and malondialdehyde (MDA) levels in the healing of dermal wounds. Healing was evaluated by measuring wound contractions and protein contents in the healing wounds. Cellular redistribution and collagen deposition were assessed morphologically using cross-sections of paraffin-embedded day-10 wounds stained according to the Van Gieson method. GPx and SOD activities as well as MDA levels were determined in homogenates of day-10 dermal wounds. Results showed that PVE had a greater potency to enhance wound repair and induce the increase in free radical-scavenging enzyme activities than α-Toc. Both PVE and α-Toc, however, were potent antioxidants and significantly reduced the lipid peroxidation levels in the wounds as measured by the reduction in MDA levels.

Tocotrienol rich fraction supplementation improved lipid profile and oxidative status in healthy older adults: A randomized controlled study

BackgroundVitamin E supplements containing tocotrienols are now being recommended for optimum health but its effects are scarcely known. The objective was to determine the effects of Tocotrienol Rich Fraction (TRF) supplementation on lipid profile and oxidative status in healthy older individuals at a dose of 160 mg/day for 6 months.MethodsSixty-two subjects were recruited from two age groups: 35-49 years (n = 31) and above 50 years (n = 31), and randomly assigned to receive either TRF or placebo capsules for six months. Blood samples were obtained at 0, 3rd and 6th months.ResultsHDL-cholesterol in the TRF-supplemented group was elevated after 6 months (p < 0.01). Protein carbonyl contents were markedly decreased (p < 0.001), whereas AGE levels were lowered in the > 50 year-old group (p < 0.05). Plasma levels of total vitamin E particularly tocopherols were significantly increased in the TRF-supplemented group after 3 months (p < 0.01). Plasma total tocotrienols were only increased in the > 50 year-old group after receiving 6 months of TRF supplementation. Changes in enzyme activities were only observed in the > 50 year-old group. SOD activity was decreased after 3 (p < 0.05) and 6 (p < 0.05) months of TRF supplementation whereas CAT activity was decreased after 3 (p < 0.01) and 6 (p < 0.05) months in the placebo group. GPx activity was increased at 6 months for both treatment and placebo groups (p < 0.05).ConclusionThe observed improvement of plasma cholesterol, AGE and antioxidant vitamin levels as well as the reduced protein damage may indicate a restoration of redox balance after TRF supplementation, particularly in individuals over 50 years of age.

Tocotrienol-Rich Fraction Prevents Cell Cycle Arrest and Elongates Telomere Length in Senescent Human Diploid Fibroblasts

This study determined the molecular mechanisms of tocotrienol-rich fraction (TRF) in preventing cellular senescence of human diploid fibroblasts (HDFs). Primary culture of HDFs at various passages were incubated with 0.5 mg/mL TRF for 24 h. Telomere shortening with decreased telomerase activity was observed in senescent HDFs while the levels of damaged DNA and number of cells in G0/G1 phase were increased and S phase cells were decreased. Incubation with TRF reversed the morphology of senescent HDFs to resemble that of young cells with decreased activity of SA-β-gal, damaged DNA, and cells in G0/G1 phase while cells in the S phase were increased. Elongated telomere length and restoration of telomerase activity were observed in TRF-treated senescent HDFs. These findings confirmed the ability of tocotrienol-rich fraction in preventing HDFs cellular ageing by restoring telomere length and telomerase activity, reducing damaged DNA, and reversing cell cycle arrest associated with senescence.

Oxidative damage and antioxidant status in patients with cervical intraepithelial neoplasia and carcinoma of the cervix

Free radicals that induced lipid peroxidation and DNA damage have been implicated in many diseases including cancer. Cellular antioxidant defense plays an important role in neoplastic disease to counteract oxidative damage. This study aims to investigate the status of oxidative damage by measuring plasma malondialdehyde (MDA) level and urinary 8-hydroxydeoxyguanosine (8-OHdG), and the level of antioxidant enzymes superoxide dismutase, glutathione peroxidase, and catalase in patients with cervical intraepithelial neoplasia (CIN) and squamous cell carcinoma (SCC) of the cervix. Urinary 8-OHdG was measured by an enzyme-linked immunosorbent assay kit. MDA and antioxidant enzyme activities were determined by high-performance liquid chromatography and spectrophotometry, respectively. Eighty patients with CIN and SCC of the cervix were recruited and compared with normal controls. Urinary 8-OHdG/creatinine ratio did not show any significant changes in any disease status studied as compared with controls (P=0.803). Plasma MDA was found to be increased in CIN and SCC patients when compared with controls (P=0.002). Glutathione peroxidase activity was increased (P=0.0001) whereas superoxide dismutase and catalase activity was decreased (P=0.019 and 0.0001, respectively) in both CIN and SCC patients when compared with controls. Urinary 8-OHdG may not be a good marker for enhanced oxidative stress in cervical cancer. Oxidative damage as demonstrated by the level of MDA is markedly increased in CIN and SCC patients with changes of enzymatic antioxidants observed.

Efficacy of fasting calorie restriction on quality of life among aging men

Calorie restriction (CR) has been promoted to increase longevity. Previous studies have indicated that CR can negatively affect mood and therefore the effect of CR on mood and quality of life (QOL) becomes crucial when considering the feasibility of CR in humans. We conducted a three month clinical trial on CR (reduction of 300 to 500 kcal/day) combined with two days/week of Muslim sunnah fasting (FCR) to determine the effectiveness of FCR on QOL among aging men in Klang Valley, Malaysia. A total of 25 healthy Malay men (age 58.8±5.1 years), with no chronic diseases and a BMI of 23.0 to 29.9 kg/m2 were randomized to FCR (n=12) and control (n=13) groups. Body composition measurements and QOL questionnaires were ascertained at baseline, week 6 and week 12. QOL was measured using the Short-Form 36, sleep quality was determined using the Pittsburgh Sleep Quality Index, the Beck Depression Inventory II was used to measure mood and the Perceived Stress Scale was used to measure depression. The FCR group had a significant reduction in body weight, BMI, body fat percentage and depression (P<0.05). The energy component of QOL was significantly increased in FCR group (p<0.05). There were no significant changes in sleep quality and stress level between the groups as a result of the intervention. In conclusion, FCR resulted in body weight and fat loss and alleviated depression with some improvement in the QOL in our study and has the potential to be implemented on a wider scale.

γ-Tocotrienol Prevents Oxidative Stress-Induced Telomere Shortening in Human Fibroblasts Derived from Different Aged Individuals

The effects of palm γ-tocotrienol (GGT) on oxidative stress-induced cellular ageing was investigated in normal human skin fibroblast cell lines derived from different age groups; young (21-year-old, YF), middle (40-year-old, MF) and old (68-year-old, OF). Fibroblast cells were treated with γ-tocotrienol for 24 hours before or after incubation with IC50 dose of H2O2 for 2 hours. Changes in cell viability, telomere length and telomerase activity were assessed using the MTS assay (Promega, USA), Southern blot analysis and telomere repeat amplification protocol respectively. Results showed that treatment with different concentrations of γ-tocotrienol increased fibroblasts viability with optimum dose of 80 µM for YF and 40 µM for both MF and OF. At higher concentrations, γ-tocotrienol treatment caused marked decrease in cell viability with IC50 value of 200 µM (YF), 300 µM (MF) and 100 µM (OF). Exposure to H2O2 decreased cell viability in dose dependent manner, shortened telomere length and reduced telomerase activity in all age groups. The IC50 of H2O2 was found to be; YF (700 µM), MF (400 µM) and OF (100 µM). Results showed that viability increased significantly (p < 0.05) when cells were treated with 80 µM and 40 µM γ-tocotrienol prior or after H2O2-induced oxidative stress in all age groups. In YF and OF, pretreatment with γ-tocotrienol prevented shortening of telomere length and reduction in telomerase activity. In MF, telomerase activity increased while no changes in telomere length was observed. However, post-treatment of γ-tocotrienol did not exert any significant effects on telomere length and telomerase activity. Thus, these data suggest that γ-tocotrienol protects against oxidative stress-induced cellular ageing by modulating the telomere length possibly via telomerase.

Vitamin C and aloe vera supplementation protects from chemical hepatocarcinogenesis in the rat

The effects of vitamin C and aloe vera gel extract supplementation on induced hepatocarcinogenesis in male Sprague-Dawley rats (120-150 g) by diethylnitrosamine (DEN) and 2-acetylaminofluorene (AAF) was investigated. The severity of the carcinogenesis process was determined by measuring gamma-glutamyl transpeptidase (GGT) and the placental form of glutathione S-transferase (GSTP) histochemically in situ and in plasma and liver fractions. In addition, plasma alkaline phosphatase (ALP) and liver microsomal uridine diphosphate glucuronyl transferase (UDPGT) activity were also determined. Administration of DEN/AAF caused an increase in the surface area and number of enzyme-positive foci (both GGT and GSTP) compared with control. Supplementation of vitamin C or aloe vera gel extract to the cancer-induced rats suppressed this increase significantly (P < 0.05; P < 0.001). Increases in liver UDPGT, GGT, and GSTP activities were also observed with cancer induction that were again suppressed with either vitamin C or aloe vera gel supplementation. Plasma GGT in the DEN/AAF rats were determined monthly for the duration of the experiment and found to be reduced as early as 1 mo with aloe vera gel supplementation and 2 mo with vitamin C supplementation. In conclusion, vitamin C and aloe vera gel extract supplementation were found to be able to reduce the severity of chemical hepatocarcinogenesis.