mRNA Expression Levels Of α-SMA Research Articles

Effects of MAL gene knockout on lung tissue morphology and on E-cad and α-SMA expression in asthma mouse models

Objectives To investigate the effects of myelin- and lymphocyte-associated protein (MAL) gene knockout on the morphological structure of lung tissue and the expression of E-cadherin (E-cad) and alpha-smooth muscle actin (α-SMA) in an asthmatic mouse model. Methods Twenty-four specific pathogen-free (SPF) C57BL/6J mice were divided into four groups: the wild-type normal (WT/SAL), wild-type asthmatic (WT/OVA), gene knockout normal (MAL-/-/SAL), and gene knockout asthmatic (MAL-/-/OVA) groups. The establishment of the asthma mouse models was confirmed by evaluating behavioral symptoms and histopathological H&E and Masson staining. Western blotting and RT–qPCR were used to measure E-cad and α-SMA expression levels in lung tissues. Results H&E staining of mouse lung tissues from WT/OVA, MAL-/-/SAL, and MAL-/-/OVA groups revealed a thickened bronchial wall, irregular lumen edge, locally fallen mucosal epithelium, and inflammatory cell infiltration compared with those of the WT/SAL group. In the WT and MAL-/- groups, the proportion of Masson-stained tissues in the OVA group was greater than that in the SAL group (p < 0.05). Compared with those in the WT/SAL group, the expression levels of α-SMA mRNA and protein were increased, while those of E-cad were decreased in the WT/OVA group (p < 0.01). Similarly, compared with those in the MAL-/-/SAL group, the expression levels of E-cad mRNA and protein were increased, while those of α-SMA were decreased in the MAL-/-/OVA group (p < 0.01). All these differences were statistically significant (p < 0.01). Conclusions The MAL gene contributes to EMT inhibition and the stability of the airway barrier under normal physiological conditions by regulating E-cad and α-SMA expression.

Improving depression-like behaviors caused by diabetes is likely to offer a new perspective for the treatment of non-healing chronic wounds.

Three phases are often involved in the intricate process of wound healing: inflammatory exudation, cell proliferation, and tissue remodeling. It is challenging for wounds to heal if conditions like ischemia, persistent pressure, infection, repetitive trauma, or systemic or localized illnesses arise during the healing process. Chronic wounds are persistent injuries that do not follow the normal healing process and fail to progress through the stages of healing within a reasonable timeframe, like diabetic ulcers, vascular ulcers, pressure sores, and infectious wounds. Various factors affect chronic wound healing. A large body of research has illuminated that psychological distress may often be related to wound healing in clinical settings. Our observations have indicated that the pace of wound healing in diabetic mice is generally slower than that of healthy mice, and mice induced by streptozotocin (STZ) and fed a high-fat diet generally exhibit depression-like behavior. Our experiment delves into whether there is an inherent correlation and provides new ideas for clinical treatment to promote wound healing. In order to explore the relationship between diabetes, depression, and wound healing, we observed wound healing through HE staining, Masson's trichrome staining, and IHC staining for CD31 and detected the depressive condition through behavioral tests. Then, RT-PCR was used to detect the mRNA expression levels of α-SMA, Col1, CD31, and VEGF in wound tissue. Finally, the related brain areas were regulated through chemical genetic methods and the process of wound healing was observed. It has been observed that the lateral habenula (LHb) areas are associated with depression-like behavior induced by diabetes. Inhibiting LHb neuronal activity mitigates these depressive symptoms and enhances wound healing. Refractory wounds can be improved by considering patients' emotional issues from a broad standpoint, which provides fresh concepts for potential clinical treatments in the future.

Effect of Gualou Xiebai Decoction on pulmonary fibrosis in rats based on pyroptosis pathway

This study investigated the effect of Gualou Xiebai Decoction on rats with bleomycin-induced pulmonary fibrosis. The rats were randomly divided into a control group, a model group, a low-dose Gualou Xiebai Decoction group(2.4 g·kg~(-1)), a high-dose Gualou Xiebai Decoction group(4.8 g·kg~(-1)), and pirfenidone group(150 mg·kg~(-1)). The model of pulmonary fibrosis was established by intratracheal instillation of bleomycin in all groups, except the control group. Since the second day of modeling, the corresponding drugs were given to rats by intragastric administration, once a day for 14 d and 28 d. The hematoxylin-eosin(HE) staining was used to evaluate the degree of inflammatory injury in lung tissues. The immunofluorescence staining was used to detect the expression of CD68 and CD163 in lung tissues of rats. The levels of tumor necrosis factor-α(TNF-α) and interleukin-10(IL-10) in serum and brochoalveolar lavage fluid(BALF) were detected by enzyme-linked immunosorbent assay(ELISA). The expression of pyroptosis-related genes in lung tissues of rats was detected by qRT-PCR. The results of HE staining and immunofluorescence staining showed that the lung tissue structure was normal in the control group. In addition, there were alveolar collapse or even closure in lung tissues of rats in the model group, with obvious inflammatory cell infiltration, and the expression of CD68 and CD163 was significantly up-regulated. As compared with the model group, the lung tissue structure of rats in the Gualou Xiebai Decoction groups was significantly improved, with alleviated inflammation, and the expression of CD68 and CD163 was decreased. As compared with the control group, the level of TNF-α in serum and BALF of rats in the model group was significantly increased(P&lt;0.01), the mRNA expression levels of alpha smooth muscle actin(α-SMA), collagen type Ⅰ alpha 1 chain(Col1a1), caspase-1, IL-1β, IL-18, gasdermin D(Gsdmd), and NOD-like receptor thermal protein domain associated protein 3(NLRP3) in lung tissues were significantly increased(P&lt;0.05, P&lt;0.01), and the mRNA expression level of E-cadherin was significantly decreased(P&lt;0.01). As compared with the model group, the level of TNF-α in serum and BALF was significantly down-regulated in the high-dose Gualou Xiebai Decoction group(P&lt;0.05, P&lt;0.01), and that of IL-10 was up-regulated(P&lt;0.05, P&lt;0.01). The mRNA expression levels of α-SMA, Col1a1, caspase-1, IL-18, Gsdmd, NLRP3 and IL-1β in lung tissues were significantly decreased(P&lt;0.05, P&lt;0.01) in the high-dose Gualou Xiebai Decoction group, and the mRNA expression level of E-cadherin was significantly increased(P&lt;0.05, P&lt;0.01). In conclusion, Gualou Xiebai Decoction can down-regulate the levels of inflammatory factors and related genes and effectively mitigate pulmonary fibrosis by regulating the pyroptosis pathways.

Aspartate Reduces Liver Inflammation and Fibrosis by Suppressing the NLRP3 Inflammasome Pathway via Upregulating NS3TP1 Expression.

Aspartate (Asp) can act on liver Kupffer cells, inhibit NOD-like receptor-P 3 (NLRP3) inflammatory bodies, and improve liver inflammation in acute hepatitis. However, the effect of Asp on the role of hepatic stellate cells (HSCs) in the pathogenesis of liver fibrosis in chronic liver injury remains unexplored. This study aimed to investigate the effects of Asp on CCl4-induced liver fibrosis in mice and HSCs via the NF-κB/NLRP3 signaling pathway. Liver fibrosis was induced in C57BL/6J mice by intraperitoneally (IP) injecting 0.5 mL/kg 2% CCl4 three times weekly for 8 weeks. Asp was administered to mice by gavage once every morning for 4 weeks. Masson's trichrome staining, Sirius red staining and hematoxylin and eosin staining were used to detect and analyze the pathological changes in liver tissues. Western blot analysis and immunohistochemistry were applied to determine the protein expression levels of α-smooth muscle actin (α-SMA), collagen Ⅲ (COL III), NLRP3, and IL-1β. In addition, reverse transcription-quantitative PCR was performed to detect the mRNA expression levels. In the liver fibrosis model, the pathological changes in liver tissues improved following treatment with Asp. A marked decrease was observed in protein and mRNA expression levels of α-SMA, COL III, NLRP3, and IL-1β. In addition, HSCs were treated with Asp. The expression levels of α-SMA, COL III, NLRP3, and IL-1β reduced in dose- and time-dependent manners. Furthermore, Asp upregulated the expression of NS3TP1 in vivo and in vitro, and NS3TP1 had a significant inhibitory effect on liver fibrosis. Asp attenuated liver fibrosis and reduced collagen production by suppressing the NF-κB/NLRP3 signaling pathway via upregulating the expression of NS3TP1.

Drug-containing serum of rhubarb-astragalus capsule inhibits the epithelial-mesenchymal transformation of HK-2 by downregulating TGF-β1/p38MAPK/Smad2/3 pathway

Ethnopharmacological relevanceRheum palmatum L; Astragalus membranaceus (Fisch.), is referred to as ‘Dahuang, Huangqi’ in China. As an important medicinal plant, the rhizome of rhubarb and astragalus is traditionally used in the treatment of kidney diseases associated with renal failure, inflammation and tumors.Aim of the study: This study aimed to investigate the effect of a drug-containing serum of rhubarb-astragalus capsules (composed of rhubarb and astragalus) and to elucidate its mechanism in the epithelial-mesenchymal transformation of renal tubular epithelial cells. Materials and methodsEpithelial-mesenchymal transformation (EMT) of HK-2 cells was induced by TGF-β1, and rhubarb-astragalus and losartan drug-containing serum from rats, as well as SB203580 (a specific inhibitor of p38 MAPK), were used. High-performance liquid chromatography analysis was performed to determine the main components of the drug-containing serum of rhubarb-astragalus from rats. Western blotting and immunofluorescence analysis were used to determine the levels of protein expression, and real-time quantitative PCR analysis was used to detect the levels of gene expression. ResultsThe drug-containing serum of rhubarb-astragalus contained emodin (0.36 μg/ml) and danthraquinone (0.96 μg/ml). Rhubarb-astragalus significantly decreased the protein expression levels of α-SMA, FN, vimentin and N-cadherin in HK-2 cells that were increased by TGF-β1, while it significantly increased the E-cadherin protein expression level that was decreased by TGF-β1. Rhubarb-astragalus also significantly decreased the protein expression levels of TGF-β1 and p38 MAPK and the mRNA expression levels of α-SMA, vimentin, TGF-β1, p38 MAPK, Smad2 and Smad3 in HK-2 cells that were increased by TGF-β1. It is worth noting that SB203580 (a p38 MAPK inhibitor) had similar effects as rhubarb-astragalus in this study. ConclusionThe drug-containing serum of rhubarb-astragalus can inhibit EMT in HK-2 cells by downregulating the TGF-β1/p38 MAPK/Smad2/3 pathway.

Role of interleukin-6 in human umbilical vein endothelial cell to mesenchymal cell transformation

Role of interleukin-6 in human umbilical vein endothelial cell to mesenchymal cell transformation

Anti-fibrotic effects of brevilin A in hepatic fibrosis via inhibiting the STAT3 signaling pathway

Hepatic fibrosis is a chronic liver disease characterized by the accumulation of extracellular matrix (ECM). Activation of hepatic stellate cells (HSCs) after repetitive liver damage is a key event in hepatic fibrogenesis. As part of ongoing research projects to identify pharmacologically effective natural products, the phytochemical investigation of a MeOH extract of Centipeda minima led to the isolation of a sesquiterpene lactone, brevilin A, which was explored to elucidate potential anti-fibrotic effects by reversing HSC activation. First, we observed that transforming growth factor (TGF)-β1 treatment significantly increased the expression levels of HSC activation marker, α-smooth muscle actin (α-SMA), and ECM protein such as collagen and fibronectin. Then, we demonstrated that brevilin A reversed the TGF-β1-induced increase in protein and mRNA expression levels of α-SMA and collagen. To investigate the underlying molecular mechanism of brevilin A, we evaluated the effects of brevilin A on the STAT3 signaling pathway. STAT3 phosphorylation, increased by TGF-β1 treatment, was strongly inhibited by brevilin A; the expression levels of fibronectin and connective tissue growth factor were also significantly decreased by brevilin A. The present study indicated that brevilin A has a preventive and therapeutic potential against hepatic fibrosis.

FoxM1 inhibition ameliorates renal interstitial fibrosis by decreasing extracellular matrix and epithelial–mesenchymal transition

FoxM1 is a transcriptional regulator involved in tumor development, pulmonary fibrosis, and cardiac fibrosis. However, its role in renal interstitial fibrosis (RIF) has yet to be elucidated. We established a TGF-β1-stimulated human proximal tubular epithelial cell (HK-2) model in vitro and a unilateral ureteral obstruction (UUO)-induced rat RIF model in vivo. FoxM1 inhibition was achieved by siRNA interference in vitro and by injecting thiostrepton into UUO-induced RIF rats in vivo. The degree of renal damage and fibrosis were determined by histological assessment via hematoxylin and eosin (H&E) staining. Immunohistochemistry, western blots, and qPCR were used to determine the expression levels of FoxM1, Collagen I, E-cadherin, α-SMA, and Snail1. Our results showed that FoxM1 inhibition could ameliorate RIF and reduce the deposition of Collagen I. H&E staining revealed that renal structural damage, inflammatory cell infiltration, and ECM deposition were significantly attenuated by thiostrepton treatment in the UUO rats. Furthermore, FoxM1 downregulation significantly suppressed epithelial-to-mesenchymal transition, as evidenced by decreased protein and mRNA expression levels of α-SMA and Snail1 and a significant increase in protein and mRNA expression levels of E-cadherin. Collectively, these results suggested that FoxM1 inhibition could be a novel therapeutic strategy for the treatment of RIF.

Therapeutic Potential of Thrombomodulin in Renal Fibrosis of Nephrotoxic Serum Nephritis in Wistar-Kyoto Rats

Background: Recombinant human soluble thrombomodulin (rhTM) was approved in 2008 and has been used for treatment of disseminated intravascular coagulation in Japan. The antifibrotic effects of rhTM in acute exacerbation of idiopathic pulmonary fibrosis are well established, but the therapeutic potential of rhTM in renal fibrosis remains poorly understood. Methods: Nephrotoxic serum nephritis (NTS-N) was induced in 22 female Wistar-Kyoto (WKY) rats on day 0. Rats were administered either rhTM or vehicle intraperitoneally, every day from day 4 to day 55. Rats were sacrificed on day 56 when renal fibrosis was established and renal morphological investigations were performed. In vitro, rat renal fibroblasts (NRK-49F) were pretreated with rhTM or saline, and expression levels of profibrogenic gene induced by thrombin were analyzed by real-time reverse transcription polymerase chain reaction. Results: Compared to WKY-GN-vehicle rats, the body weights of WKY-GN-rhTM rats were significantly greater on day 55. By day 56, rhTM had significantly reduced serum creatinine levels in NTS-N. On the other hand, urinary protein excretion was comparable between the two treatment groups throughout the study. The percentage of Masson trichrome-positive areas in WKY-GN-rhTM rats was significantly lower compared to that in WKY-GN-vehicle rats. Glomerular fibrin deposition was significantly reduced in WKY-GN-rhTM rats. In addition, rhTM significantly reduced the renal cortical mRNA expression levels of TNF-α, Toll-like receptor 4, MYD88, TGF-β, αSMA, collagen I, collagen III, fibronectin, and protease-activated receptor 1 (PAR1), a thrombin receptor. In vitro, thrombin stimulation of NRK-49F cells significantly enhanced the mRNA expression levels of αSMA and PAR1, and these upregulations were significantly reduced by pretreatment with rhTM. Conclusions: Administration of rhTM after establishment of crescentic glomerulonephritis (GN) attenuated the subsequent development of renal fibrosis in NTS-N, possibly in part by inhibiting thrombin-mediated fibrogenesis. Our results suggest that rhTM may offer a therapeutic option for limiting the progression of chronic kidney disease in crescentic GN.

Endothelin-1-induced expression of α-smooth muscle actin in human myometrial fibroblasts.

We aimed to investigate the potential role of endothelin-1 (ET-1) in the regulation of the expression of α-smooth muscle actin (α-SMA) in human myometrial fibroblasts. Primary myometrial fibroblasts were obtained from myometrium and were identified by immunocytochemical staining. Then, 1 × 107 cells were treated with ET-1 at a concentration of 0.1, 1.0, 10.0, or 100.0 nM for 24 h. To investigate the time course effects of ET-1 on the growth of fibroblasts, 1 × 107 cells were treated with 10.0 nM ET-1 for 6, 12, 24, and 48 h. Real-time quantitative PCR (qPCR) and Western blot analysis were used to determine the expression of α-SMA mRNA and protein, respectively. Human myometrial fibroblasts were identified by immunohistochemistry. Compared with the control group, the expression levels of α-SMA mRNA and protein were identified in cells treated with ET-1 at a concentration of 0.1, 1.0, 10.0, or 100.0 nM for 24 h (P < 0.05). ET-1 treatment affected the expression of α-SMA mRNA and protein in a dose-dependent manner (P < 0.05). The induction of α-SMA mRNA and protein expression increased from 6 to 48 h. The results show that ET-1 induces the expression of α-SMA in human myometrium in vitro.

Effects of silencing Smad ubiquitination regulatory factor 2 on the function of human hypertrophic scar-derived fibroblasts

Effects of silencing Smad ubiquitination regulatory factor 2 on the function of human hypertrophic scar-derived fibroblasts

Curcumin suppresses transforming growth factor-β1-induced cardiac fibroblast differentiation via inhibition of Smad-2 and p38 MAPK signaling pathways.

The differentiation of cardiac fibroblasts (CFs) into myofibroblasts and the subsequent deposition of the extracellular matrix is associated with myocardial fibrosis following various types of myocardial injury. In the present study, the effect of curcumin, which is a pharmacologically-safe natural compound from the Curcuma longa herb, on transforming growth factor (TGF)-β1-induced CFs was investigated, and the underlying molecular mechanisms were examined. The expression levels of α-smooth muscle actin (SMA) stress fibers were investigated using western blotting and immunofluorescence in cultured neonatal rat CFs. Protein and mRNA expression levels of α-SMA and collagen type I (ColI) were determined by western blotting and reverse transcription-quantitative polymerase chain reaction. In addition, the activation of Smad2 and p38 was examined using western blotting. Curcumin, SB431542 (a TGF-βR-Smad2 inhibitor) and SB203580 (a p38 inhibitor) were used to inhibit the stimulation by TGF-β1. The results demonstrated that the TGF-β1-induced expression of α-SMA and ColI was suppressed by curcumin at the mRNA and protein levels, while SB431542 and SB203580 induced similar effects. Furthermore, phosphorylated Smad-2 and p38 were upregulated in TGF-β1-induced CFs, and these effects were substantially inhibited by curcumin administration. In conclusion, the results of the present study demonstrated that treatment with curcumin effectively suppresses TGF-β1-induced CF differentiation via Smad-2 and p38 signaling pathways. Thus, curcumin may be a potential therapeutic agent for the treatment of cardiac fibrosis.

Effects of 5-azacytidine on radiation-induced epithelial-mesenchymal transition in rat alveolar type II epithelial cell line

Objective To investigate the effects of 5-azacytidine on radiation-induced epithelial-mesenchymal transition in rat alveolar type Ⅱ epithelial cell line ( RLE-6TN) and explore their working mechanisms, and to provide experimental evidence for the potential drug-based treatment of radiation-induced pulmonary fibrosis. Methods RLE-6TN cells were cultured in vitro and divided into four groups according to the experimental purposes : control group (C) , radiation group (R), 5-azacytidine group (A), and radiation followed by 5-azacytidine group ( R + A). The microstructural changes in cells were determined by transmission electron microscopy. Inverted phase-contrast microscopy revealed the morphological changes in cells. The mRNA expression levels of E-cadherin and α-SMA were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression levels of E-cadherin, GSK3β, and p-GSK3β (Ser9) were measured by Western blot. The one-way analysis of variance was used for pairwise comparison. Results The cells in group R became spindle-like. Similar morphological changes were not observed in cells in group R + A. Osmiophilic lamellar bodies disappeared at last in cells in group R. RT-PCR results showed that compared with group C, group R had a significantly lower mRNA expression level of E-cadherin ( (0. 23 ± 0. 06 ) vs. (1.00 ± 0.00 ) , P = 0. 002 )) and a significantly higher mRNA expression level of α-SMA (( 2. 91 ± 0.01) vs. (1. 00 ± 0. 00), P=0.000)). However, compared with group R, group R + A had a significantly higher mRNA expression level of E-cadherin ((0. 47 ±0. 05) vs. (1.00 ± 0. 00), P = 0.024)) but a significantly lower mRNA expression level of α-SMA ((2.50 ± 0. 02) vs. (1.00 ± 0.00), P=0. 037)). The results of Western blot showed that the protein expression level of E-cadherin was significantly reduced ((0. 07 ± 0. 01) vs. (0. 48 ± 0. 02), P=0. 028 )), while the protein expression level of p-GSK3β was significantly increased in Group R than in Group C ( (0. 85 ±0.04) vs. (0.23 ±0. 03), P = 0. 031)). However, compared with group R, group R + A had a significantly lower protein expression level of E-cadherin ( (0. 25 ± 0. 00) vs. (0. 07 ± 0. 01), P = 0. 024)) and significantly less up-regulation of the protein expression level of p-GSK3β (( 0. 39 ± 0. 03 ) vs. ( 0. 85 ± 0. 04 ), P = 0.014)). Conclusions X-ray radiation can induce the epithelial-mesenchymal transition in epithelial cells. 5-azacytidine suppresses radiation-induced epithelial-mesenchymal transition by inhibition of the activity of p-GSK3p in RLE-6TN cells. Key words: 5-Azacytidine; X-ray irradiation; RLE-6TN cell line; Epithelial-mesenchymal transition; Rat

Effects of breviscapine on epithelial-mesenchymal transition induced by transforming growth factor-β2 in human lens epithelial cells

Background Epithelial-mesenchymal transition (EMT) is a major event in the pathogenesis of posterior capsular opacification (PCO),and the expressions of α-smooth muscle actin (α-SMA) is the marker of EMT.Previous studies showed that breviscapine plays an important role in anti-fibrosis and suppression EMT,however,the mechanism of its effect on EMT in LECs is unclear.Objective Present study was to investigate the effect of breviscapine on the expression of α-SMA and fibronectin (FN) in human LECs induced by transforming growth factor-β2 (TGF-β2).Methods Human LECs strain,HLE-B3,was cultured and passaged in DMEM containing 10％ fetal bovine serum.Different concentrations of breviscapine (6.75,12.75,25.00,50.00 and 100.00 mg/L)were added into the medium for 24,48 and 72 hours respectively,and then cell cunting kit-8 (CCK-8) was used to evaluate the half maximal inhibitory concentration (IC50) of breviscapine to HLE-B3.In addition,HLE-B3 was subcultured at the density of 1 × 106/hole and divided into 4 groups.The cells were in free-serum medium as the normal control;the cells were exposed in 10 μg/L TGF-β2 as TGF-β2 group;while in the breviscapine group,10 mg/L of breviscapine was added into the culture medium and another group was the combination of 10 mg/L breviscapine and 10 μg/L of TGF-β2 treatment.Real-time PCR and Western blot were used to detect the mRNA expressions of α-SMA and FN as well as their protein in HLE-B3 72 hours after cultured.Results The inhibitory rate of breviscapine to HLE-B3 proliferation was gradually elevated with the increase of concentration of breviscapine,showing a significant inhibition of the cell proliferation among the different groups and at various time points (F =292.851,P=0.000;F =65.037,P=0.000).IC50 of HLE-B3 at 72 hours was 22 mg/L,and therefore,in rest of experiment 10 mg/L of breviscapine was used which was 1/2 only half of the IC50.α-SMA and FN were expressed in cultured normal HLE-B3.The expressing level of α-SMA mRNA and FN mRNA in the HLE-B3 was significantly different among the normal group,TGF-β22 group,breviscapine treatment group and combination group as well as at various time points (F =105.490,P =0.000 ; F =1041.414,P =0.000).Similarly,the protein expressions of α-SM A and FN in the HLE-B3 was significantly different among the four groups and different time points (F=136.872,P=0.000;F=119.820,P=0.000).The expression levels of α-SMA and FN mRNA and their proteins in HLE-B3 were remarkably increased in the 10 μg/L TGF-β2 group compared with the normal control group (at all P=0.000),and those in the combination group were obviously declined in comparison to the TGF-β2 group (P =0.001,0.001,0.001,0.010).No significant difference was found in the expressions of α-SMA and FN in the HLE-B3 between the breviscapine group and normal control group in both transcriptional level and protein level (P =0.551,0.292,0.551,0.360).Conclusions 10 mg/L breviscapine can arrest the proliferation and EMT of human LECs.This result suggests that using breviscapine may be a potential prophylactic approach in the prevention of PCO. Key words: Breviscapine; Lens epithelial cell; Epithelial-mesenchymal transition; Posterior capsular opacification

Polyprenols from Taxus chinensis var. mairei prevent the development of CCl4-induced liver fibrosis in rats

Ethnopharmacological relevanceThe aim of this study was to investigate the anti-fibrotic effects and the possible underlying mechanisms of taxus polyprenols (TPs) isolated from the needles of Taxus chinensis var. mairei. Materials and methodsThe animals were randomly divided into normal control with vehicles only (olive oil), rat model given CCl4 only, CCl4+low TPs (48mg/kg), CCl4+medium TPs (120mg/kg), CCl4+high TPs (300mg/kg), and CCl4+Polyene phosphatidylcholine (PP, 120mg/kg). The rat model of liver fibrosis was induced by subcutaneous injection of 40% (v/v) of CCl4 diluted in olive oil (3mL/kg body weight) twice per week for 8 weeks. Liver histopathological study was performed. Aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and albumin (ALB) of the serum were determined for evaluating the liver function. In order to reveal the possible mechanisms of the anti-fibrotic effects, oxidative stress level, hepatic collagen metabolism, and hepatic stellate cells (HSCs) activation were investigated. Furthermore, the mRNA expression of the fibrotic-related factors was measured by the quantitative real-time RT-PCR. ResultsTPs successfully attenuated liver injury induced by CCl4 shown by histopathological sections of livers and improved liver function as indicated by decreased ALT, AST and ALP levels and increased ALB levels in serum of the rats. TPs significantly increased the hepatic Cu/Zn SOD and GSH-Px activities along with GSH content while a remarkable decrease in MDA content. Both immunohistochemical staining and mRNA expression levels of α-SMA indicated a profound suppression of HSCs activation. Furthermore, it significantly inhibited the mRNA expression of the pro-fibrotic cytokines Col α1(I), Col α1(Ш), MMP-2, TIMP-1, TIMP-2, PDGF-β, TGF-β1, CTGF and TNF-α and restored the hepatoprotective factor HGF. ConclusionThese results suggest that the protective effects of TPs in chronic CCl4-induced liver fibrosis might be related with the reduction of oxidative damage, the inhibition of HSCs activation, the down-regulation of pro-fibrogenic stimuli and the protection of hepatocytes.