Metagonimus yokogawai: metacercariae survey in fishes and its development to adult worms in various rodents.

A parasitological survey for Metagonimus yokogawai metacercariae was carried out by examining a total of 321 freshwater fish comprising of 7 species. Of the 321 fish samples examined, 182 (56.7%) were found to be infected with M. yokogawai metacercariae. The prevalence of M. yokogawai metacercariae in Opsariichthys pachycephalus was 93.4% (86/92), Zacco platypus 75.0% (30/40), Distoechodon turmirostris 61.3% (38/62), Varicorhinus barbatulus 56.5% (13/23), Hemibarbus labeo 33.3% (1/3), Acrossocheilus formosanus 15.9% (14/88), and 0% in Sinibrama macrops (0/13), respectively. This is the first record of M. yokogawai infection in Z. platypus, D. turmirostris, V. barbatulus, and H. labeo in Taiwan. The major site of predilection of the metacercariae in the fishes was in the scale, but some metacercariae were also observed in the flesh and fins. The M. yokogawai metacercariae were orally inoculated into mice, rat, gerbil, and golden hamster to study their infectivity and also to obtain the adult worms for taxonomic study. Worm recovery in hamsters was 75.3%, in mice was 70.0%, in rats was 23.3%, and in gerbils was 6.0%, respectively. Moreover, larger worms were recovered from the golden hamster. Golden hamster was thus found to be the most susceptible experimental rodent host for the infectivity study of Metagonimus. Besides M. yokogawai, metacercariae of Centrocestus formosanus was also observed in the fishes examined.

Urokinase induces stromal cell-derived factor-1 expression in human hepatocellular carcinoma cells.

Both the urokinase-type plasminogen activator (uPA) and the uPA receptor (uPAR) play important roles with regard to hepatocellular carcinoma (HCC) progression and metastasis. Notably, the stromal cell-derived factor-1 (SDF-1) is an important chemokine involved in HCC pathology. However, the influence of uPA on SDF-1 expression in human HCC cells remains unknown. We investigated the mechanisms underlying the modulation of SDF-1 expression through uPA stimulation in human HCC SK-Hep-1 cells. SK-Hep-1 cells stimulation with uPA induced increases in the expression and secretion of SDF-1. By using specific inhibitors and small interfering RNA, we have demonstrated that the activation of extracellular signal-related kinase (ERK) and c-Jun-NH(2)-terminal kinase (JNK) pathways are critical for uPA-induced SDF-1 expression. Transcription factor ELISA and chromatin immunoprecipitation assays suggest that uPA increase Sp1- and AP-1-DNA-binding activities in SK-Hep-1 cells. Inhibition of Sp1 and AP-1 activations by specific siRNAs blocked the uPA-induced SDF-1 promoter activity and expression. The effect of uPA on SK-Hep-1 signaling and SDF-1 expression is mediated by uPAR. In summary, our findings serve to elucidate the uPA/uPAR downstream signaling, providing new insight into the function of uPA in HCC cells.

Tournefortia sarmentosa extract attenuates acetaminophen-induced hepatotoxicity.

CONTEXT: Tournefortia sarmentosa Lam. (Boraginaceae), a Chinese herbal medicine, is commonly used as a detoxicant or anti-inflammatory agent. OBJECTIVE: As acetaminophen (APAP) is a well-known hepatotoxin, we investigated the effect of the aqueous extract of the T. sarmentosa on APAP-induced hepatotoxicity in vivo and in vitro. MATERIALS AND METHODS: Levels of liver function markers serum glutamate oxaloacetate transaminase (SGOT), glutamate pyruvate transaminase (SGPT), and alkaline phosphatase (ALP), inflammatory markers tumor necrosis factor (TNF)-α, interleukin (IL)-1b, and IL-6 in serum, and antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), as well as lipid peroxidation were determined. RESULTS: T. sarmentosa significantly reduced the elevated liver function (SGOT, SGPT, and ALP, p < 0.01) and inflammatory markers (TNF-α, IL-1ß, and IL-6, p < 0.01) in serum of APAP-intoxicated rats. Malondialdehyde level (p < 0.05) and antioxidant enzyme levels (CAT, SOD, and GPx, p < 0.05) were also reduced in APAP-intoxicated rats treated with T. sarmentosa. Incubation of rat hepatocyte cell line clone-9 cells with APAP reduced cell viability and increased the extent of lipid peroxidation. APAP stimulation also reduced the level of glutathione (GSH) and caused reduction in the activities of the antioxidant enzymes, CAT, SOD, and GPx. Pretreatment of hepatocytes with T. sarmentosa aqueous extract before and during APAP stimulation attenuated the extent of lipid peroxidation, increased cell viability and GSH level, and enhanced the activities of antioxidant enzymes. DISCUSSION AND CONCLUSION: These data suggest that the aqueous extract of T. sarmentosa can prevent APAP-induced hepatotoxicity.

Baicalein inhibits the migration and invasive properties of human hepatoma cells.

Flavonoids have been demonstrated to exert health benefits in humans. We investigated whether the flavonoid baicalein would inhibit the adhesion, migration, invasion, and growth of human hepatoma cell lines, and we also investigated its mechanism of action. The separate effects of baicalein and baicalin on the viability of HA22T/VGH and SK-Hep1 cells were investigated for 24h. To evaluate their invasive properties, cells were incubated on matrigel-coated transwell membranes in the presence or absence of baicalein. We examined the effect of baicalein on the adhesion of cells, on the activation of matrix metalloproteinases (MMPs), protein kinase C (PKC), and p38 mitogen-activated protein kinase (MAPK), and on tumor growth in vivo. We observed that baicalein suppresses hepatoma cell growth by 55%, baicalein-treated cells showed lower levels of migration than untreated cells, and cell invasion was significantly reduced to 28%. Incubation of hepatoma cells with baicalein also significantly inhibited cell adhesion to matrigel, collagen I, and gelatin-coated substrate. Baicalein also decreased the gelatinolytic activities of the matrix metalloproteinases MMP-2, MMP-9, and uPA, decreased p50 and p65 nuclear translocation, and decreased phosphorylated I-kappa-B (IKB)-ß. In addition, baicalein reduced the phosphorylation levels of PKCα and p38 proteins, which regulate invasion in poorly differentiated hepatoma cells. Finally, when SK-Hep1 cells were grown as xenografts in nude mice, intraperitoneal (i.p.) injection of baicalein induced a significant dose-dependent decrease in tumor growth. These results demonstrate the anticancer properties of baicalein, which include the inhibition of adhesion, invasion, migration, and proliferation of human hepatoma cells in vivo.

Infectivity and development of Metagonimus yokogawai in experimentally infected domestic ducks (Cairina moschata).

Information concerning whether fowl such as duck is a suitable reservoir host of Metagonimus yokogawai is largely unclear to date. In the present study, the growth and development of M. yokogawai metacercaria (Mc) in domestic duck (Cairina moschata) was determined by worm recovery rate (WRR) and morphological changes e.g., the size of fluke's body as well as their internal organs was assessed by using Semichon's acetocarmine staining. Each duck was orally inoculated with 50 Mcs of M. yokogawai and infected ducks were deeply anesthetized with ether and killed at 1, 2, 3, 4, 5, 6, 7, and 14 days post-infection (DPI). On each date, two infected ducks were killed and the small intestines of each duck were separated into four parts then they were opened longitudinally to harvest the flukes. Results revealed that WRR of M. yokogawai from inoculated ducks increased during early infection with a peak as seen at 4 DPI (28.5+/-6.9%); thereafter it gradually decreased and a drastic decline was observed in 14 DPI (2.0+/-1.1%) in the trial. The preference sites for M. yokogawai were low portions of the small intestine; nevertheless the size of fluke's body and organs developed increasingly with time and they maturated to produce ova from 4 DPI onward in the trial. However, present results indicated that ducks, based on the findings of this study, are not suitable hosts for establishment of M. yokogawai infection because most flukes were expelled from duck's intestine within 14 days. Nevertheless, it was proposed that ducks might play a certain role in transmitting M. yokogawai when they deposited the ova via feces into marsh where snails and fish were abundant since they could presumably establish transient and possibly patent infections with this parasite.

Berberine induces apoptosis in SW620 human colonic carcinoma cells through generation of reactive oxygen species and activation of JNK/p38 MAPK and FasL.

Berberine is the major constituent of Coptidis Rhizoma with multiple pharmacological activities, including anti-inflammation, promotion of apoptosis and anticancer potential effect. Mitogen-activated protein kinase (MAPK) and reactive oxygen species (ROS) may contribute to the causal relationship between tumorigenesis and pro-apoptotic function. Berberine is studied for the mechanism of its action in apoptotic pathway in human colonic carcinoma cell. Treatment of SW620 cells with 50 microM berberine resulted in activation of the caspase 3 and caspase 8, cleavage of poly ADP-ribose polymerase (PARP) and the release of cytochrome c; whereas, the expression of BID and anti-apoptosis factor c-IAP1, Bcl-2, and Bcl-(XL) were decreased markedly. Berberine-induced, dose-dependent induction of apoptosis was accompanied by sustained phosphorylation of JNK and p38 MAPK, as well as generation of the ROS. Furthermore, the induction of apoptosis was alleviated by inhibitors specific for JNK and p38. In addition, there was an increase in the cellular levels of phospho-c-Jun, FasL and t-BID in the berberine-induced apoptosis via the activation of JNK and p38 signaling modules. NAC administration, a scavenger of ROS, reversed berberine-induced apoptosis effects via inhibition of JNK, p38 and c-jun activation, and FasL and t-BID expression. These results leads us to speculate that berberine may play an apoptotic cascade in SW620 cells by activation of the JNK/p38 pathway and induction of ROS production, providing a new mechanism for berberine-induced cell death in human colon cancer cells.