Wen-Huei Chang

Protective effects of Dunaliella salina : A carotenoids-rich alga, against carbon tetrachloride-induced hepatotoxicity in mice

The protective effects of Dunaliella salina (D. salina) on liver damage were evaluated by carbon tetrachloride (CCl(4))-induced hepatotoxicity in mice. Male ICR mice were orally treated with D. salina or silymairn daily with administration of CCl(4) twice a week for 8 weeks. CCl(4) induced liver damage and significantly (p<0.05) increased the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in serum and decreased the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), and GSH content in liver whereas increased hepatic malondialdehyde (MDA) content as compared with control group. Treatment with D. salina or silymarin could significantly (p<0.05) decrease the ALT, AST, and ALP levels in serum and increase the activities of SOD, catalase, GSH-Px, glutathione reductase, and GSH content and decrease the MDA content in liver when compared with CCl(4)-treated group. Liver histopathology also showed that D. salina reduced the incidence of liver lesions induced by CCl(4). The results suggest that D. salina exhibits potent hepatoprotective effects on CCl(4)-induced liver damages in mice, and that the hepatoprotective effects of D. salina may be due to both the increase of antioxidant enzymes activities and inhibition of lipid peroxidation.

Hepatoprotective effect of electrolyzed reduced water against carbon tetrachloride-induced liver damage in mice.

The study investigated the protective effect of electrolyzed reduced water (ERW) against carbon tetrachloride (CCl(4))-induced liver damage. Male ICR mice were randomly divided into control, CCl(4), CCl(4)+silymarin, and CCl(4)+ERW groups. CCl(4)-induced liver lesions include leukocytes infiltration, hepatocyte necrosis, ballooning degeneration, mitosis, calcification, fibrosis and an increase of serum alanine aminotransferase (ALT), and aminotransferase (AST) activity. In addition, CCl(4) also significantly decreased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). By contrast, ERW or silymarin supplement significantly ameliorated the CCl(4)-induced liver lesions, lowered the serum levels of hepatic enzyme markers (ALT and AST) and increased the activities of SOD, catalase, and GSH-Px in liver. Therefore, the results of this study show that ERW can be proposed to protect the liver against CCl(4)-induced oxidative damage in mice, and the hepatoprotective effect might be correlated with its antioxidant and free radical scavenging effect.

Synergistic anti-cancer effect of baicalein and silymarin on human hepatoma HepG2 Cells.

This study investigated the effect of baicalein, silymarin, and their combination, on two human liver-derived cell lines, HepG2 (hepatocellular carcinoma) and Chang liver (non-tumor liver cells). It was found that 6.75 microg/ml baicalein or 100 microg/ml silymarin alone significantly inhibited the growth of HepG2. When baicalein was used in combination with silymarin on HepG2, an additive effect at 24 h and a synergistic effect at 48 h were observed. The viability at 48 h was 85.62% from 6.75 microg/ml baicalein treatment; but the viability reduced to 49.67%, 38.56%, and 19.61% when 25, 50, and 100 microg/ml silymarin respectively, was added to the treatment. By contrast, each treatment had little or no effect on Chang liver. Compared to treatment of baicalein or silymarin alone on HepG2, combination of both drugs synergistically increased the percentages of cells in G0/G1 phase and decreased those in S-phase, which were associated with up-regulation of Rb, p53, p21(Cip1) and p27(Kip1) and down-regulation of cyclin D1, cyclin E, CDK4 and phospho-Rb. The results indicate that the combination of baicalein and silymarin eradicates tumor cells efficiently, has minimal deleterious effects to the surrounding normal cells, and offers mechanistic insight for further exploitation of HCC treatment.

Enhancing effect of patented whey protein isolate (Immunocal) on cytotoxicity of an anticancer drug.

To determine the enhancing effect of a whey protein isolate on the cytotoxicity of a potential anticancer drug, baicalein, the human hepatoma cell line Hep G2 was assigned to grow in different media for four days, and cell growth and apoptosis were investigated. The control group was grown in normal medium; the other three groups were grown in whey protein isolate (Immunocal) medium, baicalein medium, and a combination of Immunocal and baicalein. As indicated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, survival rate was significantly lower in cells grown in baicalein + Immunocal than in cells grown in baicalein alone. In contrast, there was no significant difference in survival rate of the cells grown in Immunocal. In the investigation of apoptosis, cells grown in baicalein + Immunocal showed a higher phosphatidylserine exposure, lower mitochondrial transmembrane potential, and nearly 13 times more cells undergoing apoptosis than cells grown in baicalein alone. We also demonstrated that Immunocal reduced glutathione (GSH) in Hep G2 cells by 20-40% and regulated the elevation of GSH, which was in response to baicalein. In conclusion, Immunocal seemed to enhance the cytotoxicity of baicalein by inducing more apoptosis; this increase in apoptotic cells may be associated with the depletion of GSH in Hep G2 cells. This is the first study to demonstrate, in vitro, that Immunocal may function as an adjuvant in cancer treatments.

Humic acid enhances the cytotoxic effects of arsenic trioxide on human cervical cancer cells

Cervical cancer is the second leading cancer affecting women, and recent studies have demonstrated arsenic trioxide (As(2)O(3)) has therapeutic effects on cervical cancer by promoting apoptosis and inhibiting metastasis in vitro and in vivo. Humic acid (HA) possesses various pharmacologic properties, including anti-inflammatory, anti-neoplastic, and anti-proliferative effects by inducing apoptosis. We examined the growth inhibition properties and the combined effects of HA and As(2)O(3) in human cervical adenocarcinoma cell lines. Our results shown both As(2)O(3) and HA-induced inhibition of cell growth, most likely by ROS-mediated cell damage and activation of the apoptosis pathway, and HA enhanced the anti-proliferative action of As(2)O(3) in HeLa and SiHa cells, which reduced the LC(50) about 57.62 or 73.52% (300μg HA/mL) to 83.67 or 79.03% (500μg HA/mL), respectively. This study is relevant to the development of chemotherapeutic approaches using As(2)O(3) in treating human cervical cancer.

Anti-Cancer Effects of Protein Extracts from Calvatia lilacina, Pleurotus ostreatus and Volvariella volvacea

Calvatia lilacina (CL), Pleurotus ostreatus (PO) and Volvariella volvacea (VV) are widely distributed worldwide and commonly eaten as mushrooms. In this study, cell viabilities were evaluated for a human colorectal adenocarcinoma cell line (SW480 cells) and a human monocytic leukemia cell line (THP-1 cells). Apoptotic mechanisms induced by the protein extracts of PO and VV were evaluated for SW480 cells. The viabilities of THP-1 and SW480 cells decreased in a concentration-dependent manner after 24 h of treatment with the protein extracts of CL, PO or VV. Apoptosis analysis revealed that the percentage of SW480 cells in the SubG1 phase (a marker of apoptosis) was increased upon PO and VV protein-extract treatments, indicating that oligonucleosomal DNA fragmentation existed concomitantly with cellular death. The PO and VV protein extracts induced reactive oxygen species (ROS) production, glutathione (GSH) depletion and mitochondrial transmembrane potential (ΔΨm) loss in SW480 cells. Pretreatment with N-acetylcysteine, GSH or cyclosporine A partially prevented the apoptosis induced by PO protein extracts, but not that induced by VV extracts, in SW480 cells. The protein extracts of CL, PO and VV exhibited therapeutic efficacy against human colorectal adenocarcinoma cells and human monocytic leukemia cells. The PO protein extracts induced apoptosis in SW480 cells partially through ROS production, GSH depletion and mitochondrial dysfunction. Therefore, the protein extracts of these mushrooms could be considered an important source of new anti-cancer drugs.

Lipid peroxidation and cell death mechanisms in rats and human cells induced by chloral hydrate

Chloral hydrate (CH) is widely used as a sedative and hypnotic in pediatric medicine. It is also a by-product of water chlorination and a metabolite of trichloroethylene. We examined the toxicological effects and cell death mechanisms of CH in rats and human Chang liver cells and lymphocytes. Monitoring of urinary 8-epi-PGF2alpha and serum levels of TNF-alpha served as index of lipid peroxidation and cytokine stimulation. The results indicated that a single intraperitoneal injection of 100 mg/kg CH in rats led to a nearly five-fold increase in urinary 8-epi-PGF2alpha on day 1, and a mild decrease on day 2 and day 3. The same treatment also induced significantly higher amounts of serum TNF-alpha on day 2 (about seven-fold). When the rats were treated with CH and vitamin E simultaneously, the amount of urinary 8-epi-PGF2alpha and serum TNF- were significantly lower than that in the rats treated with CH alone. CH caused a greater cytotoxic effect in human Chang liver cells than in comparison with lymphocytes. After treatment with CH, apoptosis features were observed in human lymphocytes, but not Chang liver cells. CH-induced cell damage in lymphocytes may offer signals for the induction of caspases activation. Further studies are needed to evaluate the relationship between caspases activation and the cleavage of other death substrates during postmitotic apoptosis in human lymphocytes.

The Antioxidant Effects of Propofol in Menadione-Induced Oxidative Stress in Human Monocyte THP-1 Cells

Background: Propofol, thiopental, citosol, and midazolam are widely used as sedatives for the critically ill in the intensive care unit. These patients usually suffer from cellular injuries caused by oxidative stress from free radicals, predominantly due to the lack of a sufficient defense system against these species. Therefore, the antioxidant activities of sedative drugs may be clinically important. We attempt to evaluate the antioxidant and reactive oxygen species scavenging activities of these clinically relevant intravenous sedatives. Methods: By using Menadione, Hydrogen peroxide and Cumene hydroperoxide to create oxidative stress in human monocyte THP-1 cell line, we evaluate the antioxidative activity of propofol, thiopental, citosol, and midazolam by means of flow cytometry to investigate the intracellular reactive oxygen species scavenging ability of these drugs in human monocyte THP-1 cell line. Results: Propofol expressed an excellent scavenging activity compared with the other intravenous anesthetics, especially on menadione-induced superoxide in THP-1 cells. Propofol also significantly inhibits the intracellular GSH depletion and the decrease of mitochondrial transmembrane potential (△Ψ(subscript m)) induced by menadione in THP-1 cells. The expression of two antioxidant enzymes, superoxide dismutase (SOD) and gamma-glutamylcysteine synthetase (y-GCS), is inhibited by menadione treatment. Pretreatment with propofol can maintain the expression of SOD and y-GCS in menadione-treated THP-1 cells. The expression of another antioxidant enzyme, catalase, is not obviously affected by menadione and propofol. Conclusions: Propofol, of the four drugs tested in the present study, showed the most antioxidant and reactive oxygen species scavenging activities.