• Natural Product Sciences
• /
• v.19 no.3
• /
• pp.231-235
• /
• 2013

Activity-guided isolation to search for antifibrotic compounds from natural products using HSC-T6 cells afforded nine flavonoids or phenolics, luteolin (1), 3'-O-methylorobol (2), acactin 7-rutinoside (3), sedelolactone (4), 4-methoxyphenol (5), 4-hydroxyaldehyde (6), 4-hydoxyaldehyde (7), 4-hydroxy-3-methoxybenzoic acid (8), and ferulic acid (9) from the methanolic extract of aerial parts of Eclipta prostrata L.. Among the isolated compounds, luteolin (1) significantly inhibited the proliferation of HSCs in dose- and time-dependent manners. Antifibrotic activity of E. prostrata and its phenolic compounds might provide potential therapeutical choice in the treatment of hepatic fibrosis.

• Natural Product Sciences
• /
• v.14 no.2
• /
• pp.118-121
• /
• 2008

Manassantin B, a dilignan isolated from Saururus chinensis, significantly inhibited proliferation in HSC-T6 cells in concentration- and time-dependent manners. In addition, treatment of HSC-T6 cells with manassantin B changed cell morphology from flattened myofibroblastic membranous morphology, representing activation state, to slender shape, representing quiescent state. Furthermore, manassantin B effectively reduced collagen content in HSC-T6 cells. These results suggested that manassantin B exerted antifibrotic activity in HSCT6 cells, in part, via inhibition of cell proliferation and decrease of collagen production.

• Natural Product Sciences
• /
• v.15 no.2
• /
• pp.101-105
• /
• 2009

We previously reported that a novel cerebroside, LCC, isolated from the fruits of Lycium chinense (Solanaceae), significantly exerted hepatoprotective activity against both the carbon tetrachloride-induced and galactosamine-induced toxicities in primary cultures of rat hepatocytes. In the present study, we further attempted to determine the effect of LCC on hepatic fibrosis in animal model. Hepatic fibrosis was induced in rats by bile duct ligation/scission (BDL) for a period of 5 weeks. Treatment of BDL rats with LCC significantly reduced collagen deposition and the activities of serum alkaline phosphatase and ${\gamma}$-glutamyl transpeptidase. In addition, the LCC treatment of BDL rats significantly preserved the decreased hepatic glutathione as well as the activities of glutathione reductase and catalase in BDL rats. From the results, it can be speculated that LCC might exert antifibrotic activity in rats with BDL, in part, through the preservation of antioxidant enzymes and hepatic glutathione.

• Natural Product Sciences
• /
• v.16 no.4
• /
• pp.280-284
• /
• 2010

During liver fibrosis, hepatic stellate cells (HSCs) undergo a complex activation process characterized by increased proliferation and extracellular matrix deposition, which is the major pathological feature of hepatic cirrhosis. Therefore, suppression of HSCs activation has been proposed as therapeutic strategies for hepatic fibrosis. We tried to screen the antifibrotic activity of natural products employing HSC-T6, hepatic stellate cell lines as an in vitro assay system. In the present study, we investigated the antiproliferative activity of aerial parts and roots of Pulsatilla koreana Nakai (Ranunculaceae). Our present study shows that roots of P. koreana exerted more strong inhibitory activity compared to its aerial parts. In addition, among the fractions of the aqueous methanolic extract of P. koreana roots, both n-hexane and $CHCl_3$ fraction showed the strong inhibitory activity on HSC proliferation. Further study also demonstrated that the n-hexane and $CHCl_3$ fraction of P. koreana roots significantly inhibited the HSC proliferation in time- and concentration-related manners.

• Archives of Pharmacal Research
• /
• v.23 no.5
• /
• pp.501-506
• /
• 2000

We examined the antifibrotic effect of a methanol extract from Stephania tetrandra (ST) on experimental liver fibrosis. liver fibrosis was induced by bile duct ligation and scission (BDL/S) in rats. In BDL/S rats, activity levels of aspartate transaminase (AST), alanine transaminse (ALT), alkaline phosphatase (ALP), concentration of total bilirubin in serum, and hydroxyproline content of the liver were significantly increased. The ST treatment (either 100 ${m}g/kg/day$ or 200 ${m}g/kg/day$, p.o. for 4 weeks) in BDL/S rats reduced the serum AST, ALT and ALP activity levels significantly (p<0.01). Similarly, when compared to the control group, the concentration of hydroxyproline in the livers of the BDL/S rats treated with 100${m}g$ or 200${m}g$ ST treated rats decreased by 40% and 33% respectively, when compared to the BDL/S control group (p<0.01). The morphological characteristics of fibrotic liver that were observed in the BDL/S control group, improved in the ST treated BDL/S group. In the fibrotic liver of BDL/S rats treated with ST, a marked reduction in the numbers of alpha smooth muscle cell actin positive stellate cells was observed. These results indicate that doses of either 100 or 200 ${m}g/kg/day$ of methanol extract from S. tetrandra, had an antifibrotic effect in rats with liver fibrosis induced by bile duct ligation and scission.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.5 no.1
• /
• pp.61-64
• /
• 2000

A series of 5-oxaproline peptide derivatives was synthesized and evaluated for its ability to inhibit the prolyl 4-hydroxylase in vitro. Structure-activity studies show that the 5-oxaproline sequences, prepared by the 1,3-dipolar cycloaddition of the C-methoxycarbonyl-N-mannosyl nitrone in the presence of the ethylene, are more active than the corresponding proline derivatives. Prolyl 4-hydroxylase belongs to a family of $Fe^{2+}-dependent$ dioxygenase, which catalyzes the formation of 4-hydroxyproline in collagens by the hydroxylation of proline residues in -Gly-Xaa-Pro-Gly- of procollagen chains. In this paper we discover the more selective N-Cbz-Gly-Phe-Pro-Gly-OEt $(K_m\;=\;520\;{\mu}M)$ sequences which are showed stronger binding than others in vitro. Therefore, we set out to investigate constrained tetrapeptide that was designed to mimic the proline structure of pep tides for the development of prolyl 4-hydroxylase inhibitor. From this result, we found that the most potent inhibitor is N-Dansyl-Gly-Phe-5-oxaPro-Gly-OEt $(K_i\;=\;1.6\;{\mu}M)$. This has prompted attempts to develop drugs which inhibit collagen synthesis. Prolyl 4-hydroxylase would seem a particularly suitable target for antifibrotic therapy.

• Natural Product Sciences
• /
• v.17 no.3
• /
• pp.216-220
• /
• 2011

Activation of hepatic stellate cells (HSCs) characterized by increased proliferation and extracellular matrix deposition is identified as the major pathological feature of hepatic cirrhosis. Therefore, suppression of HSC activation has been proposed as an important antifibrotic therapeutic strategy. In the present study, we investigated the antiproliferative activity of root barks of Ulmus davidiana var. japonica (Ulmaceae) by employing HSC-T6 hepatic stellate cells as an in vitro assay system. Further investigation of the n-hexane and $CHCl_3$ fractions of root barks of U. davidiana var japonica led to the isolation of six triterpenoids: friedelin (1), epifridelanol (2), oleanolic acid (3), maslinic acid (4), ${\beta}$-amyrin (5) and ${\alpha}$-amyrin (6), together with ${\beta}$-sitosterol (7) and daucosterol (8). Among these compounds, 2, 3 and 4 significantly inhibited HSC proliferation. In addition, 4 inhibited HSC proliferation in time- and concentration-related manners, via a partially direct toxic effect, as assessed by morphological changes and release of lactate dehydrogenase.

• Korean Journal of Medicinal Crop Science
• /
• v.17 no.4
• /
• pp.243-250
• /
• 2009

Fifty percent ethanol extract of Lythrum salicaria Linne root (LSR) was tested in vitro on antioxidant activity, and furthermore was investigated on antioxidative and fibrosis protecting activities in $CCL_4$-induced liver fibrosis rat model. Ratio of hepatic GSH/GSSG (reduced glutathione/oxidized glutathione) as bio-parameter of antioxidant level in $CCL_4$ plus LSR-treated rats for 6 weeks significantly increased from 2.8- to 5.7-fold than that of $CCL_4$-treated rats at p < 0.05. Thiobarbituric acid reactive substances (TBARS) contents in $CCL_4$ plus LSR-treated rats ranged from 1.57- to 2.19-fold of normal rats and were lower than those in $CCL_4$ plus silymarin-treated rats ($1.78{\sim}2.46$-fold of normal rats) (p < 0.05). Amounts of hydroxyproline of liver tissue showing the content of total collagen, a parameter of fibrosis, in $CCL_4$ plus LSR-administrated rat livers were $4.9{\sim}8.8{\mu}g$/mg ($-47{\sim}-71%$, compared with that in $CCL_4$-treated rat livers ($16.6{\mu}g$/mg tissue), which were significantly lower than those in $CCL_4$ plus silymarin-administrated rats being $8.4{\sim}11.7{\mu}g$/mg ($-30{\sim}-50%$). This collagen reducing effect of liver tissue in $CCL_4$ plus LSR-treated rats was supported by histological observation using microscopy assay. From the results, we conclude that the root of L. salicaria have efficient antioxidant potential and effective antifibrotic activities.

• Journal of Applied Biological Chemistry
• /
• v.50 no.2
• /
• pp.78-84
• /
• 2007

The anti-fibrotic effects of hot water extract of adventitious root culture of Panax ginseng (ARCP) and the possible mechanisms were investigated on $CCl_4-induced$ hepatotoxicity model mice. Fibrosis was induced by a mild treatment of $CCl_4$. Then silymarin as a positive control drug and ARCP or carrier alone as a negative control were treated. Serum GPT, GOT and ALP activity levels were lowered by 25, 21 and 11% for silymarin treated group and by 48, 39 and 14% for ARCP treated group compared to carrier treated alone. Hepatic collagen for ARCP treatment group was reduced by 18% and MDA contents decreased a little more. Pro-fibrotic gene ($TGF-{\beta}1$, TIMP-1 and ${\alpha}-SMA$) expression increased following the $CCl_4$ treatment, but both the silymarin and the ARCP treatments decreased the expressions of these genes by 20% to 50%. The antioxidant effect of ARCP was studied by DPPH free radical scavenging activity. In addition, a generation of reactive oxygen species (ROS) was also reduced in $H_2O_2-treated$ HepG2 cells upon the ARCP treatment. In summary, ARCP has antioxidant property, and can have some protection against oxidative stress; more importantly, ARCP can efficiently protect mice against $CCl_4-induced$ fibrosis.

• Toxicological Research
• /
• v.25 no.2
• /
• pp.71-78
• /
• 2009

We investigated the pathogenesis of liver tissue damage during the lipid peroxidation and fibrogenesis with the observation of correlations between the parameters of collagen synthesis (and deposition) and lipid peroxidation in liver fibrosis (cirrhosis) rats. Rats were randomly divided into two groups, normal and $CCl_4$-thiopental sod. intoxicated group. And the one group was treated intragastrically with the mixture of $CCl_4$-thiopental sod. 3 times per week for 3 weeks. The liver tissue and sera were used for the measurement of hydroxyproline (HYP), malonedialdehyde (MDA) and superoxide dismutase (SOD). Biochemical parameters such as aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total-bilirubin and blood urea nitrogen (BUN) were measured. Additionally, the expression of collagen ${\alpha}1$(III) and $\beta$-actin mRNA was observed by RTPCR. The histological change in liver tissue was also observed by Masson's trichrome and H&E staining. Correlation analysis was carried by Spearman's rho method. All biochemical parameters except total-bilirubin were significantly higher in the $CCl_4$-thiopental sod. treated group than that of the normal group (p < 0.01). In the $CCl_4$-thiopental sod. treated group, Hyp as a parameter of collagen synthesis (deposition) and MDA as a metabolite of lipid peroxidation, were significantly elevated by 1.98 and 2.11 times higher than that of the normal group (p < 0.001) respectively. The activity of SOD in the $CCl_4$-thiopental sod. treated group is decreased significantly by 44.8% (p < 0.001). And collagen ${\alpha}1$(III) mRNA was more expressed in the $CCl_4$-thiopental sod. treated group than that of the normal group. However, the expression of $\beta$-actin mRNA is showed similar in both of groups. A good correlation was observed between the content of hyp and MDA concentration (r = 0.70, n = 40) in the two groups. And the correlation between the levels of hyp and SOD (r = -0.71, n = 25) is also reliable. However, no correlation were observed between MDA concentration and SOD (r = -0.40, n = 25) in the two groups. Elevated levels of MDA in $CCl_4$-thiopental sod. treated rats indicated enhancement of lipid peroxidation, which is accompanied by a decrease in SOD activity. Moreover, we could confirm that the parameters of collagen synthesis (and deposition) is in good correlation with the metabolite of lipid peroxidation (MDA) and the lipid peroxidation antagonizing enzyme (SOD). Hence, we propose that (1) lipid peroxidation and collagen synthesis (and deposition) could be enhanced by intragastrically application of $CCl_4$-thiopental sod. during a short terms. And (2) the intoxication of $CCl_4$-thiopental sod. could be used for monitoring of lipid peroxidation and collagen synthesis (and deposition) for test of antioxidant and antifibrotic agent.