• Clinics in Shoulder and Elbow
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• v.21 no.1
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• pp.3-14
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• 2018

Background: Platelet-rich plasma (PRP) stimulates cell proliferation and enhances matrix gene expression and synthesis. However, there have been no comparative study of the PRP effect on the normal and degenerative tenocytes. The purpose of this study was to compare the effect of PRP on tenocytes from normal and degenerative tendon. Methods: Tendon tissues were obtained from patients undergoing arthroscopic repair (n=9) and from healthy donors (n=3). Tenocytes were cultured with 10% (vol/vol) platelet-poor plasma, PRP activated with calcium, and PRP activated with calcium and thrombin. The total cell number was assessed at days 7 and 14. The expressions of type I and III collagen, decorin, tenascin-C, and scleraxis were evaluated by quantitative real-time reverse transcriptase polymerase chain reaction. The total collagen and glycosaminoglycan (GAG) synthesis was evaluated at days 7 and 14. Results: No differences were observed between the groups at day 7, but cell proliferation was remarkably increased in tenocytes from the degenerative tendon at day 14. In both tenocyte groups, the gene expressions of type I and III collagen were up-regulated. GAG synthesis was greater in the normal tendon, whereas the expressions of decorin and tenascin-C were increased in tenocytes from the degenerative tendon. Tenocytes from the degenerative tendon had higher fold-change of GAG synthesis and a lower collagen III/I ratio than normal tenocytes. Conclusions: PRP promoted the cell proliferation and enhanced the synthesis of tendon matrix in both groups. PRP has a greater positive effect on cell proliferation, matrix gene expression and synthesis in tenocytes from degenerative tendon.

• Clinics in Shoulder and Elbow
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• v.24 no.4
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• pp.224-230
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• 2021

Background: Local anesthetics often are used in rotator cuff tears as therapeutic tools, although some cases have reported that they have detrimental effects. Neurotropin (NTP) is used widely in Japan as a treatment for various chronic pain conditions and is shown to have protective effects on cartilage and nerve cells. In this study, we investigated the protective effect of NTP against lidocaine-induced cytotoxicity. Methods: Tenocytes from rotator cuff tendons were incubated with lidocaine, NTP, lidocaine with NTP, and a control medium. Cell viability was evaluated using the WST-8 assay. Cell apoptosis was detected via annexin V staining using flow cytometry. The expression of BCL-2 and cytochrome c, which are involved in the intrinsic mitochondrial pathway of apoptosis, was evaluated via Western blotting and immunohistochemical staining. Results: In the cell viability assay, lidocaine decreased cell viability in a dose-dependent manner, and NTP did not affect cell viability. Moreover, NTP significantly inhibited the cytotoxic effect of lidocaine. The flow cytometry analysis showed that lidocaine significantly induced apoptosis in tenocytes, and NTP considerably inhibited this lidocaine-induced apoptosis. Western blotting experiments showed that lidocaine decreased the protein expression of BCL-2, and that NTP conserved the expression of BCL-2, even when used with lidocaine. Immunohistochemical staining for cytochrome c showed that 0.1% lidocaine increased cytochrome c-positive cells, and NTP suppressed lidocaine-induced cytochrome c expression. Conclusions: NTP suppresses lidocaine-induced apoptosis of tenocytes by inhibiting the mitochondrial apoptotic pathway. Intra-articular/bursal injection of NTP with lidocaine could protect tenocytes in rotator cuff tendons against lidocaine-induced apoptosis.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.297-303
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• 2019

Corticosteroids are commonly used for pain control in rotator cuff tear. Deregulated $NF-{\kappa}B$ activation is a hallmark of chronic inflammatory diseases and has been responsible for the pathogenesis of rotator cuff tear. The Dexamethasone(DEXA) is a synthetic corticosteroid. The purpose of this study was to examine the exact effect of dexamethasone on $NF-{\kappa}B$ signaling in rotator cuff tear. We measured $NF-{\kappa}B$ expression in four groups: control, $TNF-{\alpha}$-treated, DEXA-treated, and combined treatment with $TNF-{\alpha}$ and DEXA. Tenocytes were isolated from patients with rotator cuff tears and pre-incubated with $TNF-{\alpha}$ (10 ng/ml), DEXA ($1{\mu}M$), or both of them for 10 min, 1 h, and 2 h. Expression of p65, p50, and p52 in the nuclei and cytosol was analyzed by western blotting and immunofluorescence imaging using confocal microscopy. We also evaluated nucleus/cytosol (N/C) ratios of p65, p50, and p52. In our study, the combined treatment with DEXA and $TNF-{\alpha}$ showed increased N/C ratios of p65, p50, and p52 compared with those in the $TNF-{\alpha}$ group at all time points. Additionally, in the DEXA group, N/C ratios of p65, p50, and p52 gradually increased from 10 min to 2 h. In conclusion, DEXA promoted the nuclear localization of p65, p50, and p52, but was not effective in inhibiting the inflammatory response of $TNF-{\alpha}$-stimulated rotator cuff tear.

• Journal of Ginseng Research
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• v.46 no.4
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• pp.526-535
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• 2022

Background: During the pathogenesis of tendinopathy, the chronic inflammation caused by the injury and apoptosis leads to the generation of scars. Ginsenoside Rg1 (Rg1) is extracted from ginseng and has anti-inflammatory effects. Rg1 is a unique phytoestrogen that can activate the estrogen response element. This research aimed to explore whether Rg1 can function in the process of tendon repair through the estrogen receptor. Methods: In this research, the effects of Rg1 were evaluated in tenocytes and in a rat model of Achilles tendinitis (AT). Protein levels were shown by western blotting. qRT-PCR was employed for evaluating mRNA levels. Cell proliferation was evaluated through EdU assay and cell migration was evaluated by transwell assay and scratch test assay. Results: Rg1 up-regulated the expression of matrix-related factors and function of tendon in AT rat model. Rg1 reduced early inflammatory response and apoptosis in the tendon tissue of AT rat model. Rg1 promoted tenocyte migration and proliferation. The effects of Rg1 on tenocytes were inhibited by ICI182780. Rg1 activates the insulin-like growth factor-I receptor (IGF1R) and MAPK signaling pathway. Conclusion: Rg1 promotes injured tendon healing in AT rat model through IGF1R and MAPK signaling pathway activation.

• Applied Microscopy
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• v.36 no.2
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• pp.93-99
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• 2006

Gemifloxacin is a synthetic fluoroquinolone antimicrobial agent that exhibits potent activity against most Gram-negative and Gram-positive organisms, and has a comparatively low chondrotoxic potential in immature animals. This study examined the effects of gemifloxacin on the Achilles tendons in immature Sprague-Dawley rats treated by oral intubation once daily for 5 consecutive days from postnatal week 4 onward at doses of 0 (vehicle), and 600mg/kg body weight Ofloxacin was used for comparison. The Achilles tendon sperimens were examined by electron microscopy. In comparison with the vehicle-treated controls, there were ultrastructural changes in all samples from the gemifloxacin- and ofloxacin-treated rats. Degenerative changes were observed in the tenocytes, and the cells that detached from the extracellular matrix were recognizable. The degree of degenerative changes and the number of degenerated cells in the Achilles tendon were significantly higher in the treated group than in the control group. Moreover, among the quinolone treated groups, these findings were more significant in the ofloxacin treated group, and less significant in the gemifloxacin treated group. It is unclear what these findings mean with respect to the possible risk ill juvenile patients treated with gemifloxacin or other quinolones. However, these results show that gemifloxacin causes fewer changes in the connective tissue structures.