• BMB Reports
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• v.45 no.6
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• pp.348-353
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• 2012

L-2-Oxothiazolidine-4-carboxylic acid (OTC) is a cysteine prodrug that maintains glutathione in tissues. The present study was designed to investigate anti-fibrotic and anti-oxidative effects of OTC via modulation of nuclear factor erythroid 2-related factor 2 (Nrf2) in an in vivo thioacetamide (TAA)-induced hepatic fibrosis model. Treatment with OTC (80 or 160 mg/kg) improved serum liver function parameters and significantly ameliorated liver fibrosis. The OTC treatment groups exhibited significantly lower expression of ${\alpha}$-smooth muscle actin, transforming growth factor-${\beta}1$, and collagen ${\alpha}1$ mRNA than that in the TAA model group. Furthermore, the OTC treatment groups showed a significant decrease in hepatic malondialdehyde level compared to that in the TAA model group. Nrf2 and heme oxygenase-1 expression increased significantly in the OTC treatment groups compared with that in the TAA model group. Taken together, these results suggest that OTC restores the anti-oxidative system by upregulating Nrf2; thus, ameliorating liver injury and a fibrotic reaction.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.527-536
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• 2020

Liver fibrosis constitutes a significant health problem worldwide due to its rapidly increasing prevalence and the absence of specific and effective treatments. Growing evidence suggests that apoptosis-signal regulating kinase 1 (ASK1) is activated in oxidative stress, which causes hepatic inflammation and apoptosis, leading to liver fibrogenesis through a mitogen-activated protein kinase (MAPK) downstream signals. In this study, we investigated whether selonsertib, a selective inhibitor of ASK1, shows therapeutic efficacy for liver fibrosis, and elucidated its mechanism of action in vivo and in vitro. As a result, selonsertib strongly suppressed the growth and proliferation of hepatic stellate cells (HSCs) and induced apoptosis by increasing Annexin V and TUNEL-positive cells. We also observed that selonsertib inhibited the ASK1/MAPK pathway, including p38 and c-Jun N-terminal kinase (JNK) in HSCs. Interestingly, dimethylnitrosamine (DMN)-induced liver fibrosis was significantly alleviated by selonsertib treatment in rats. Furthermore, selonsertib reduced collagen deposition and the expression of extracellular components such as α-smooth muscle actin (α-SMA), fibronectin, and collagen type I in vitro and in vivo. Taken together, selonsertib suppressed fibrotic response such as HSC proliferation and extracellular matrix components by blocking the ASK1/MAPK pathway. Therefore, we suggest that selonsertib may be an effective therapeutic drug for ameliorating liver fibrosis.

• Toxicological Research
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• v.26 no.3
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• pp.193-201
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• 2010

Hepatic fibrosis represents the main complication of most chronic liver disorders and, regardless of its etiology, is characterized by excessive deposition of extracellular matrix components. In this study, we examined that 1-O-Hexyl-2,3,5-Trimethylhydroquinone (HTHQ), a potent anti-oxidative agent, could prevent experimental hepatic fibrosis induced by dimethylnitrosamine (DMN) in male SD rats. Except for vehicle control group, other groups were induced hepatic fibrosis by intraperitoneal injection with DMN (10 mg/ml/kg) on 3 consecutive days weekly for 4 weeks. During the same 4 weeks, control and DMN groups were given vehicle and HTHQ 50, 100 and 200 groups were orally administered HTHQ (50, 100, 200 mg/kg respectively). In HTHQ 100 and 200 groups, relative liver weight and serum chemistry level improved significantly. HTHQ reduced hydroxyproline (p < 0.05) and malondialdehyde (p < 0.05) level in the liver. Histopathological examination of H&E, Masson's trichrome stain showed the reduced fibrotic septa in HTHQ 100 and 200 groups. HTHQ administration showed reduced mRNA level of PDGF (Platelet-derived growth factor), $\alpha$-SMA ($\alpha$-smooth muscle actin) and TGF-$\beta$ (transforming growth factor-$\beta$) than DMN-induced hepetic fibrosis animals in the liver tissue. In this study, we showed that HTHQ improves against DMN-induced liver fibrosis in male SD rats.

• Journal of Gastric Cancer
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• v.2 no.2
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• pp.101-104
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• 2002

Schwannoma of the stomach is a rare controversial neoplasm which requires extensive studies to clarify its nature as a stromal tumor or leiomyoma. We describe the pathologic, immunohistochemical, and ultrastructural characteristics of schwannoma of the stomach in a 33-year-old woman. The tumor was a well-circumscribed submucosal mass located in the posterior wall of the midbody of the stomach. Microscopically, the cells were made up of fasciculating bundles of spindle cells featured with peripheral lymphoid cell cuffing. The tumor cells revealed a diffuse, strong immunoreactivity to S-100 protein and vimentin, but were negative to desmin and smooth muscle actin. They also had a focal positive reaction to glial fibrillary acidic protein. Ultrastructurally, many tumor cells showed a number of thin, elongated and interdigitating dendritic-cell-like processes, distinctly uniformed basal laminae, frequent cellular attachments, and microfilaments. These findings support the schwannian nature of the tumor.

• Clinical and Experimental Pediatrics
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• v.54 no.5
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• pp.224-227
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• 2011

A sclerosing stromal tumor of the ovary is an extremely rare benign tumor; it usually is found during the second and third decades of life. Patients present with pelvic pain or a palpable abdominal mass. Hormonal effects such as masculinization are uncommon. Here, an 11-year old premenarchal girl presented with deepening of the voice. In addition, clitoromegaly and hirsutism with a male suprapubic hair pattern were observed. The laboratory findings showed that the testosterone level was elevated to 3.67 ng/ml, andostenedione to above 10 ng/ml, dehydroepiandrosterone-sulfate to 346 ${\mu}g$/dl and 17-hydroxy progesterone (17-OHP) to 11.28 ng/ml. The chromosome evaluation revealed a 46,XX female karyotype. An adrenocorticotropic hormone stimulation test was performed. The 17-OHP to cortisol ratio in 30 minutes was 0.045, which suggested a heterozygote for the 21-hydroxylase deficiency. However, the CYP21A2 gene encoding steroid 21-hydroxylase showed normal. The pelvic ultrasound showed a heterogeneous mass consisting of predominantly solid tissue in the pelvic cavity. The pelvic magnetic resonance imaging revealed an $8.9{\times}6.2{\times}6.6$ cm mass of the left ovary. A left oophrectomy was performed and microscopic examination confirmed a sclerosing stromal tumor. Immunohistochemical studies showed that the tumor was positive for smooth muscle actin and vimentin, but negative for S-100 protein and cytokeratin. Following surgery, the hormone levels returned to the normal range and the hirsutism resolved.

• The Journal of Korean Physical Therapy
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• v.27 no.3
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• pp.140-146
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• 2015

Purpose: To determine the effects of 630 nm light emitting diode (LED) on full-thickness wound healing. Methods: Twelve male Sprague-Dawley rats were randomly divided into LED (n=6) and control group (n=6). Two $19.63mm^2$ wounds were created on the mid dorsum. LED group received a 630 nm LED irradiation with $3.67mW/cm^2$ for 30 minutes ($6.60J/cm^2$) for 7 days, while control group received sham LED irradiation. Epithelial gap, collagen density, ${\alpha}$-SMA fibroblast and PCNA keratinocyte were measured on histochemical and immunohistochemical staining using image analysis system. An independent t-test was conducted to compare the difference between groups. Results: The wound closure rate, collagen density, ${\alpha}$-SMA fibroblast number, epithelial gap and PCNA keratinocyte number have shown no significant difference between LED and control group at day 3 after the treatment. At day 7 after the treatment, the wound closure rate in LED group was increased when compared with control group (p<0.05). The collagen density (p<0.05) and ${\alpha}$-SMA immunoreactive fibroblast number (p<0.001) were increased when compared with control group at day 7. The epithelial gap in LED group was significantly shorten than control group at day 7 (p<0.01). The PCNA positive cell number in LED group was higher than control group at day 7 (p<0.01). Conclusion: 630 nm LED with $3.67mW/cm^2$, $6.60J/cm^2$ accelerate collagen deposition by stimulating fibroblasts, and enhance wound contraction by differentiating myofibroblasts in the dermis, and accelerate keratinocyte proliferation by facilitating DNA synthesis in the epidermis. It may promote the healing process in proliferation stage of wound healing.

• Biomolecules & Therapeutics
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• v.15 no.4
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• pp.261-265
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• 2007

Hydroxyproline (HYP) is a post-translational product of proline hydroxylation catalyzed by an enzyme prolyl 4-hydroxylase (P4H) which plays a crucial role in the synthesis of all collagens. Considering the role of collagen and its significance in many clinically important diseases such as liver fibrosis, a great deal of attention has been directed toward the development of an assay at cell-based system. The reason is that cell-based assay system is more efficient than enzyme-based in vitro system and takes much less time than in vivo system. Several assay procedures developed for P4H are laborious, time-consuming and not feasible for the massive-screening. Here, we report the cell-based assay method of prolyl 4-hydroxylase in immortalized rat hepatic stellate HSC-T6 cells. To optimize the cell culture condition to assay for HYP content, various concentrations of reagents were treated for different times in HSC-T6 cells. Our data showed that the treatment with ascorbate in a hypoxic condition for 24 h resulted in the maximal increase of HYP by 1.8 fold. Alternatively, cobalt chloride ($5\;{\mu}M$) and ascorbate ($50\;{\mu}M$) in normoxic states exhibited similar effect on the production of HYP as in a hypoxic condition. Therefore, cobalt chloride can be substituted for a hypoxic condition when an anaerobic chamber is not available. Rosiglitazone and HOE077, known as inhibitors of collagen, synthesis decreased P4H enzyme activity by 32.3% and 15%, respectively, which coincided with previous reports from liver tissues. The level of the smooth muscle ${\alpha}$-actin, a marker of activated stellate cells, was significantly increased under hypoxia, suggesting that our experimental condition could work for screening the anti-fibrotic compounds. The assay procedure took only 3 days after treatment with agents, while assays from the primary stellate cells or liver tissues have taken several weeks. Considering the time and expenses, this assay method could be useful to screen the compounds for the inhibitor of prolyl 4-hydroxylase.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3307-3312
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• 2015

The papillary patterned lesion of thyroid may be challenging with many diagnostic pitfalls. Tumor stroma plays an important part in the determination of the tumor phenotype. CD34 is thought to be involved in the modulation of cell adhesion and signal transduction as CD34(+) fibrocytes are potent antigen-presenting cells. Smooth muscle actin (SMA) positivity could be diagnostic for fibroblast activation during tumorigenesis. We aimed to examine the expression of CD34 and alphaSMA in the stroma of papillary thyroid hyperplasia, papillary thyroid carcinoma and papillary tumors of uncertain malignant potential in order to elucidate their possible differential distribution and roles. A total number of 54 cases with papillary thyroid lesions were studied by routine H&E staining, CD34 and ASMA immunostaining. ASMA was not expressed in benign papillary hyperplastic lesions while it was expressed in papillary carcinoma, indicating that tumors have modulated stroma. Although the stroma was not well developed in papillary lesions with equivocal features of uncertain potentiality, CD34 was notable in such cases with higher incidence in malignant cases. So ASMA as well as CD34 could predict neoplastic behavior, pointing to the importance of the stromal role. Differences between groups suggest that the presence of CD34 + stromal cells is an early event in carcinogensis and is associated with neoplasia, however ASMA+ cells are more likely to be associated with malignant behavior and metastatic potential adding additional tools to the light microscopic picture helping in diagnosis of problematic cases with H&E.

• Korean Journal of Veterinary Service
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• v.41 no.1
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• pp.57-61
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• 2018

Canine peripheral nerve sheath tumors (PNSTs) are spindle cell tumors that arise from Schwann cells, perineural cells, fibroblasts or all of them. Based on the morphology and biologic behavior, PNSTs are divided into benign PNST (BPNST) and malignant PNST (MPNST) forms. The aim of this study is to diagnose the two cases of neoplastic tissue samples with features of PNSTs by the histopathology and immunohistochemistry. The study was performed using two specimens from small animal clinic. The first case, A was a mass, 3~4 cm in diameter, extruded from vaginal mucosa of 10-year-old spayed female mixed-breed dog. And the second case, B was a subcutaneous mass, 1.5 cm in diameter, which is originated from right hind leg of 9-year-old castrated male mixed-breed dog. Two cases were stained with hematoxylin and eosin (H&E) for histopathological examination. And also immunohistochemistry (IHC) was performed by the avidin-biotin peroxidase complex (ABC) method with antibodies specific for the following proteins: S-100 protein, smooth muscle actin (SMA) and epidermal growth factor receptor (EGFR). In results, Antoni B schwannoma pattern characterized by pleomorphic, round and fusiform polygonal cells was seen in A. In B, Antoni A pattern, densely packed spindle cells arranged in interlacing bundles was seen in addition to Antoni B pattern. In IHC, cytoplasms of neoplastic cells were diffusely labeled for S-100 expression in A and B. For SMA, both A and B show negative expression. And for EGFR, A shows negative expression but B shows partially positive expression in areas of Antoni B schwannoma pattern. The histopathologic features of two cases coupled with the S-100 immunoreactivity led to a diagnosis of PNST. For SMA, both A and B show negative expression. The diagnosis of A will be a BPNST with the negative result and B will be a MPNST with the positive result for EGFR.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.4
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• pp.229-238
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• 2012

Cyclooxygenase(COX-2) is an inducible enzyme that catalyzes the synthesis of prostaglandins (PGs) from arachidonic acid. Over-expression of COX-2 has been reported to be associated with progressive hepatic fibrosis in chronic hepatic C infection and rat liver fibrosis induced by carbon tetrachloride($CCl_4$). Recently, it is well known that mast cell products can stimulate the proliferation of hepatic stellate cells and key players in liver fibrosis. But little is known regarding their role in $CCl_4$-induced liver fibrosis in rat. Our aim was to investigate the relation between COX-2 expression and mast cells during liver fibrosis after $CCl_4$ treatment. Thirty Wistar rats were divided into five groups (non-treated 0, 2, 4, 6 and 8-week after $CCl_4$-treatment). Reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry were used to assess the expression of ${\alpha}$-smooth muscle actin (${\alpha}$-SMA), collagen-1 and COX-2 in liver tissue from $CCl_4$-treated rats. The density of collagen and mast cells were determined using a computerized image analysis system in liver sections stained with picrosirius red and toluidine blue, respectively. The expression levels of ${\alpha}$-SMA, collagen-1 and COX-2 mRNA were significantly higher at 2 wk in $CCl_4$-treated groups than non-treated group. The number of mast cells in liver tissues increased gradually from 2 wk to 6 wk depending on the fibrosis severity but decreased abruptly at 8 wk. The significant increase of collagen-1 and ${\alpha}$-SMA mRNA expression in $CCl_4$-treated rats was continued until 6 wk while the COX-2 mRNA was significantly decreased at 8 wk. These results suggest that increased mast cells are closely associated with COX-2 over-expression during hepatic fibrogenesis of $CCl_4$-treated rats.