BACKGROUND The cytokine-induced activation of hepatic stellate cells (HSC) plays a major role in liver fibrosis.
Quiescent HSCs undergo phenotypic transformation called "transdifferentiation" in response to viral, chemical or immune insults to the liver. The cytokine TGF-beta1 plays a key role in progressive liver fibrosis. Since small interfering RNA (siRNA) is a powerful tool for silencing gene expression post-transcriptionally, the present study aimed to determine whether synthetic TGF-beta1 siRNA down-regulates the expression of the TGF-beta1 gene in immortalized and activated rat HSCs (HSC-T6s). The study examined whether synthetic TGF-beta1 siRNA prevents rat HSCs activation and extracellular matrix (ECM) production. METHODS TGF-beta1 siRNA or a control (pU6) siRNA was added to HSC-T6 culture media. We then performed RT-PCR and western blot analyses for TGF-beta1 and ECM components (fibronectin, type-I collagen, and TIMP-1). RESULTS: TGF-beta1 siRNA significantly down-regulated expression of TGF-beta1 mRNA and protein and attenuated mRNA and protein expressions of type-I collagen, fibronectin, and TIMP-1, as compared to the control. CONCLUSIONS: TGF-beta1 siRNA can effectively down-regulate the expression of TGF-beta1 in rat HSC, resulting in significant inhibition of HSC activation and of ECM production. These data indicate that synthetic TGF-beta1 siRNA can be a useful treatment modality to prevent liver fibrosis.
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Glaucocalyxin A Attenuates the Activation of Hepatic Stellate Cells Through the TGF-β1/Smad Signaling Pathway Zhichao Dong, Qi Gao, Hao Guo DNA and Cell Biology.2018; 37(3): 227. CrossRef
Jeong Hwan Park, Ho Joong Youn, Jung Sook Yoon, Chul Soo Park, Soo Sung Oh, Woo Baek Chung, Jong Won Chung, Yun Seok Choi, Dong Hyun Lee, Yong Seog Oh, Wook Sung Chung, Soon Jo Hong, Youn Soo Lee, Sung Bo Sim, Sun Hee Lee
BACKGROUND In vitro experimental studies have reported that transforming growth factor-beta1 (TGF-beta1) stimulates the production of alpha-smooth muscle actin (alpha-SMA) in porcine valves. However, the relation between TGF-beta1 and alpha-SMA in myxomatous valves has not been elucidated. METHODS We classified 27 subjects into two groups: 1) myxomatous group (M:F=11:12, mean age=55+/-15 years) and 2) rheumatic group (M:F=3:1, mean age=41+/-17 years) according to preoperative echocardiographic and postoperative histologic findings. Twenty-seven valve specimens from the patients who underwent valve replacement were obtained.
Tissue samples were analyzed by immunohistochemistry for TGF-beta1 and alpha-SMA. The positively stained areas were measured using an image analysis program (Image Pro-Plus 4.5), and then the TGF-beta1 volume fraction (TGF-VF) and alpha-SMA volume fraction (alpha-SMA-VF) were calculated. RESULTS TGF-VF in myxomatous valves was higher than in rheumatic valves (2,759+/-2,294 vs 864+/-276, p=0.04).
alpha-SMA-VF in myxomatous valves was higher than in rheumatic valves (4,122+/-2,275 vs 2,421+/-844, p=0.002).
There was a significant correlation between TGF-beta1 and alpha-SMA in myxomatous valves (r=0.38, p=0.04). There was no significant correlation between TGF-beta1 and alpha-SMA in rheumatic valves (r=-0.50, p=0.67). CONCLUSIONS TGF-beta1 and alpha-SMA may be related to the pathogenesis of myxomatous valves. The activation of TGF-beta1 might increase the expression of alpha-SMA in human myxomatous valves.
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Apoptosis and abundance of Bcl-2 family and transforming growth factor β1 signaling proteins in canine myxomatous mitral valves Sirilak Surachetpong, Treenate Jiranantasak, Anudep Rungsipipat, E. Christopher Orton Journal of Veterinary Cardiology.2013; 15(3): 171. CrossRef
Pathology, protein expression and signaling in myxomatous mitral valve degeneration: Comparison of dogs and humans Heike Aupperle, Sirilak Disatian Journal of Veterinary Cardiology.2012; 14(1): 59. CrossRef
Transforming growth factor-beta (TGF-beta) plays an important role in hepatic fibrogenesis. It is thought to inhibit regeneration of the hepatocytes. The aim of this present study was to clarify the correlation of TGF-beta, collagen type III (PIIINP) and the regenerating activity of hepatocytes, and the effect of prostaglandin E2 (PgE2) on them in acute liver injury. Two hundred and sixteen male Sprague-Dawley rats, weighing 200g on average, were divided into six experimental groups and two control groups; group I-CCl4 only administration, group II-partial hepatectomy(PH) only, group III-PH following CCl4 administration, group IV-olive oil only administration, group V-sham operation, group VI-CCl4 administration with pretreatment of PgE2, group VII- PH with pretreatment of PgE2, and group VIII- PH following CCl4 administration with pretreatment of PgE2.
Five rats were sacrificed at 12, 24, 36, 48, 96 and 168 hours after the administration of CCl4 or PH in each experimental group. The liver was tested with immunohistochemical stain for proliferating cell nuclear antigen (PCNA) and in situ hybridization for TGF-beta.
Radioimmunoassay for serum PIIINP was also performed. The results were as follows: TGF-beta was expressed mainly in the perisinusoidal cells and periportal mesenchymal cells.
The TGF-beta positive cells were most numerous in the combined group of CCl4 plus PH. TGF-beta expression tended to have an inverse relation, with the PCNA index in all experimental groups. The PCNA index was highest in the CCl4 only group and lowest in the combined group of CCl4 plus PH.
The PH only group showed a peak PCNA index at 48 hours. In the CCl4 only group and the combined group of CCl4 plus PH, serum PIIINP appeared to increase at 12 hours or more after the expression of hepatic TGF-beta. Pretreatment of PgE2 revealed that TGF-beta precipitously disappeared at 48-96 hours after insult. PgE2 influenced the vanishing period, not the emerging time of TGF-beta and had a remarkable effect on the amount of TGF-beta especially in the PH following CCl4 administration group, which resulted in significant accentuation of PCNA indices. In conclusion, PH of the prior injured liver induces a marked increase of TGF-beta followed by a significant suppression of regeneration of the remaining liver, and PgE2 overtly suppresses the expression of TGF-beta.
TGF-beta1 expression was studied in 25 patients with tuberculosis (lung, 9 cases and lymph node, 16 cases) using a polyclonal antibody in formalin-fixed paraffin embedded tissue. Nineteen cases (76.0%) out of 25 cases showed TGF-beta1 expression. TGF-beta1 was present in cytoplasm of epithelioid cells and Langhans' giant cells. Pulmonary tuberculosis and tuberculous lymphadenitis showed different patterns of staining. Five of 9 cases of pulmonary tuberculosis were positive for TGF-beta1: four of acid-fast bacilli positive cases (4/5, 80.0%) and one of acid-fast bacilli negative cases (1/4, 25.0%). However, high expression of TGF-beta1 was detected in tuberculous lymphadenitis of both acid-fast bacilli positive group (3/4, 75.0%) and acid-fast bacilli negative group (11/12, 91.7%).
TGF-beta1 was also expressed in all of 6 cases of BCG-induced tuberculous lymphadenitis: 2 acid-fast bacilli positive and 4 acid-fast bacilli negative cases. TGF-beta1 expression was shown in 19 cases (86.4%) of 22 in active tuberculosis, while no TGF-beta1 expression was detected in any cases of inactive, healed tuberculosis (p<0.008). This study supports that the TGF-beta1 expression of epithelioid cells may alter their function resulting in the impaired antimycobacterial activity. Thus the increased production of TGF-beta1 may be one of the important mechanisms by which Mycobacterium tuberculosis avoids destruction by host macrophages.
BACKGROUND In unilateral ureteral obstruction (UUO), the obstructed kidney is characterized by interstitial fibrosis and an increase in transforming growth factor (TGF)-beta1.
Interstitial expression of TGF-beta1 is important in tublointerstitial fibrosis. The objectives of this study is to make new ribbon-type antisense oligodeoxynucleotides (ODN) for TGF-beta1 which are resistant to exonuclease and to examine the effcets of TGF-beta1 on reducing tubulointerstitial fibrosis of the kidney. METHODS We introduced a new ribbon-type antisense ODN for TGF-beta1 in rats using the UUO model to block interstitial fibrosis by tail vein injection. A combination of one antisense sequences for TGF-beta1 was adopted to construct a large antisense molecule with a loop and stem. Artificial viral envelope (AVE)-type hemagglutinating virus of Japan (HVJ)-liposomes were used as a vector system for the delivery of antisense ODN. RESULTS The levels of TGF-beta1 mRNA was decreased more in the cultured mesangial cells treated with ribbon-type antisense ODN than in that of a linear-type antisense ODN for TGF-beta1. TGF-beta1 mRNA was increased markedly in the interstitium of untreated obstructed kidneys. Northem analysis revealed that the levels of TGF-beta1 mRNA were decreased in the obstructed kidneys treated with antisense ODN. The fibrosis of the obstructed kidneys treated with ribbon-type antisense ODN was dramatically less than that of the untreated group. CONCLUSIONS These results demonstrate that the introduction of new ribbon-type antisense ODN for TGF-beta1 may be a potential therapeutic maneuver for preventing interstitial fibrosis.
The immunohistochemical expression of transforming growth factor-beta(TGF-beta), epidermal growth factor(EGF) and alpha-1-antitrypsin(AAT) was studied in 47cases of endoscopic biopsy matearials of gastric carcinoma to determine me correlation to the expression of alpha fetoprotein(AFP). And immunoreactivity of the antigens was correlated to me degree of tumor infiltrating lymphocytes and histologic differentiation of the tumors. And the results were analyzed to elucidate pathological AFP-producing gastric cancer. The results were summarized as follows. AFP immunoreactivity was demonstrated in 30 cases(63.8%) of the tumors, TGF-beta in 26 cases(55.3%), EGF in l4 cases(29.8%) and AAT in l0 cases(21.3%). The incidence of expression of the antigens was significantly higher in the cases of elevated serum AFP(>2ng/ml) than that of the cases with normal serum AFP(p<0.05). There was no relation between the expression of antigens and histological differentiation of gastric cancer. The expression of AFP and TGF-beta revealed good correlation(k=0.72). The relation between expression of TGF-beta and AAT and the degree of tumor infiltrating lymphocytes disclosed negative correlation(p<0.05). These results suggest that TGF-beta and AAT prodution contribute to the worse prognosis of AFP-producting gastric cancer. Possible immunosuppressive action of TGF-beta and AAT in the cancer tissue is discussed.