ObjectivesThe aim of this study was to investigate the effect of hyperglycaemia on oxidative stress markers and inflammatory and matrix gene expression within tendons of normal and diabetic rats and to give insights into the processes involved in tendinopathy.MethodsUsing tenocytes from normal Sprague-Dawley rats, cultured both in control and high glucose conditions, reactive oxygen species (ROS) production, cell proliferation, messenger RNA (mRNA) expression of NADPH oxidase (NOX) 1 and 4, interleukin-6 (IL-6), matrix metalloproteinase (MMP)-2, tissue inhibitors of matrix metalloproteinase (TIMP)-1 and -2 and type I and III collagens were determined after 48 and 72 hours in vitro. In an in vivo study, using diabetic rats and controls, NOX1 and 4 expressions in Achilles tendon were also determined.ResultsIn tenocyte cultures grown under high glucose conditions, gene expressions of NOX1, MMP-2, TIMP-1 and -2 after 48 and 72 hours, NOX4 after 48 hours and IL-6, type III collagen and TIMP-2 after 72 hours were significantly higher than those in control cultures grown under control glucose conditions. Type I collagen expression was significantly lower after 72 hours. ROS accumulation was significantly higher after 48 hours, and cell proliferation after 48 and 72 hours was significantly lower in high glucose than in control glucose conditions. In the diabetic rat model, NOX1 expression within the Achilles tendon was also significantly increased.ConclusionThis study suggests that high glucose conditions upregulate the expression of mRNA for NOX1 and IL-6 and the production of ROS. Moreover, high glucose conditions induce an abnormal tendon matrix expression pattern of type I collagen and a decrease in the proliferation of rat tenocytes.Cite this article: Y. Ueda, A. Inui, Y. Mifune, R. Sakata, T. Muto, Y. Harada, F. Takase, T. Kataoka, T. Kokubu, R. Kuroda. The effects of high glucose condition on rat tenocytes in vitro and rat Achilles tendon in vivo. Bone Joint Res 2018;7:362–372. DOI: 10.1302/2046-3758.75.BJR-2017-0126.R2

To elucidate long-term outcome of trabeculotomy in primary and secondary developmental glaucoma. Methods: One hundred forty-nine eyes of 89 patients with developmental glaucoma who underwent trabeculotomy were retrospectively studied. Intraocular pressure (IOP), success probabilities, visual acuities, and visual field were determined during follow-up and at the final visit. Results: The mean ± SD IOP of 112 eyes with primary developmental glaucoma at the final visit with an mean±SD follow-up period of 9.5±7.1 years was 15.6±5.0 mm Hg. The average IOP for 37 eyes with secondary developmental glaucoma was 16.7 ± 4.2 mm Hg. One hundred eyes (89.3%) with primary developmental glaucoma were defined as achieving success at the final visit. Complete and qualified successes were achieved in 71 CLINICAL SCIENCES

Triamcinolone acetonide (TA) injections are widely used to treat enthesopathy, but they may induce adverse effects such as tendon impairment and rupture. Platelet-rich plasma (PRP) is a blood fraction containing high platelet concentrations and various growth factors that play a role in tissue repair processes. The purpose of this study is to investigate whether TA has deleterious effects on human rotator cuff-derived cells, and if PRP can protect these cells from the effects of TA. Human rotator cuff-derived cells were cultured with and without TA and PRP, and the culture without any additive served as the control. Cell morphology was assessed at days 7 and 21. Cell viability was evaluated at days 1, 7, 14, and 21 by a water-soluble tetrazolium salt assay. Induction of apoptosis was measured by immunofluorescence staining and flow cytometry at day 7. Induction of cleaved caspase-3 was measured by immunofluorescence staining at day 7. The cells cultured with TA had a flattened and polygonal shape at day 7. The cells cultured with both TA and PRP were similar in appearance to control cells. Exposure to TA also significantly decreased cell viability, but cell viability did not decrease when PRP was added along with TA. The number of apoptotic cells increased with TA exposure, while addition of PRP prevented cell apoptosis. In conclusion, the deleterious effect of TA was prevented by PRP, which can be used as a protective agent for patients receiving local TA injections. Keywords: triamcinolone acetonide (TA); platelet-rich plasma (PRP); rotator cuff-derived cells; apoptosis; cell viability Enthesopathy caused by rotator cuff injury clinically impairs joint function. Rotator cuff disease represents a spectrum of pathological conditions ranging from tendinosis to full-thickness tears. Conservative therapy, including rest, physical therapy, non-steroidal anti-inflammatory medications, and steroid injections are the primary treatments for these conditions. 1,2The effectiveness of subacromial steroid injections for treatment of rotator cuff tendinosis has been equivocal. 3,4 Some clinical studies have demonstrated improvement in shoulder function and decrease in shoulder pain following steroid injection.3,5 However, other studies have shown that steroids afford no clinical benefits over those provided by injections of lidocaine alone 4 or physical therapy alone. 6 Triamcinolone acetonide (TA) injections are widely used for treatment of rotator cuff tendinosis, but they may cause tendon impairment and rupture; many cases of tendon rupture after TA injections have been reported. 7-11Despite previous studies on the deleterious histological and biomechanical changes in tendons after TA injections, 8,12 TA administration is still considered to be a conservative treatment option.Platelet-rich plasma (PRP) is an autologs concentration of platelets that contains many growth factors, including platelet-derived growth factor (PDGF), transforming growth factor b (TGF-b), fibroblastic growth factor (FGF), vascular endoth...

To achieve biological regeneration of tendon-bone junctions, cell sheets of human rotator-cuff derived cells were used in a rat rotator cuff injury model. Human rotator-cuff derived cells were isolated, and cell sheets were made using temperature-responsive culture plates. Infraspinatus tendons in immunodeficient rats were resected bilaterally at the enthesis. In right shoulders, infraspinatus tendons were repaired by the transosseous method and covered with the cell sheet (sheet group), whereas the left infraspinatus tendons were repaired in the same way without the cell sheet (control group). Histological examinations (safranin-O and fast green staining, isolectin B4, type II collagen, and human-specific CD31) and mRNA expression (vascular endothelial growth factor; VEGF, type II collagen; Col2, and tenomodulin; TeM) were analyzed 4 weeks after surgery. Biomechanical tests were performed at 8 weeks. In the sheet group, proteoglycan at the enthesis with more type II collagen and isolectin B4 positive cells were seen compared with in the control group. Human specific CD31-positive cells were detected only in the sheet group. VEGF and Col2 gene expressions were higher and TeM gene expression was lower in the sheet group than in the control group. In mechanical testing, the sheet group showed a significantly higher ultimate failure load than the control group at 8 weeks. Our results indicated that the rotator-cuff derived cell sheet could promote cartilage regeneration and angiogenesis at the enthesis, with superior mechanical strength compared with the control. Treatment for rotator cuff injury using cell sheets could be a promising strategy for enthesis of tendon tissue engineering. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:289-296, 2017.

Corticosteroid injections are widely used to treat enthesopathy and tendinitis, but are also associated with possible side effects, such as tendon degeneration or rupture. However, the mechanism of tendon degeneration or rupture after corticosteroid injection remains controversial. The purpose of this study was to reveal the mechanism of tendon degeneration or rupture after injection of triamcinolone acetonide (TA) or prednisolone (PSL). Forty-two rats were divided into 3 groups: A normal saline injection group (control group), a TA injection group, and a PSL injection group; the normal saline or corticosteroid was injected around the Achilles tendon. One or 3 weeks after injection, the tendons were subjected to biomechanical testing and histological analysis. At 1 week, the biomechanical strength was significantly lower in the corticosteroid groups. Histological analysis, at 1-week post-injection, showed collagen attenuation, increased expression of MMP-3 and apoptotic cells in the corticosteroid groups. The histological changes and biomechanical weaknesses of the tendon were not seen at 3 weeks. These alterations appeared to be involved in tendon degeneration or rupture after corticosteroid injection. ß

The present data can be useful for screening pitching technique to prevent shoulder pain and injury with motion capture assessment.

ObjectivesTo investigate the appropriate dose and interval for the administration of triamcinolone acetonide (TA) in treating tendinopathy to avoid adverse effects such as tendon degeneration and rupture.MethodsHuman rotator cuff-derived cells were cultured using three media: regular medium (control), regular medium with 0.1 mg/mL of TA (low TA group), and with 1.0 mg/mL of TA (high TA group). The cell morphology, apoptosis, and viability were assessed at designated time points.ResultsIn the low TA group, the cells became flattened and polygonal at seven days then returned to normal at 21 days. The cell apoptosis ratio and messenger ribonucleic acid expression of caspase-3, 7, 8, and 9 increased, and viability was reduced in the low and high groups at seven days. In the low TA group, apoptosis and viability returned to normal at 21 days, however, in the high TA group, the cell morphology, apoptosis ratio, caspase-3, 7, 8, and 9 and viability did not return by day 21. Re-administration was performed in the low TA group at 7-, 14-, and 21-day intervals, and cell viability did not return to the control level at the 7- and 14-day intervals.ConclusionA 0.1 mg/mL dose of TA temporarily decreased cell viability and increased cell apoptosis, which was recovered at 21 days, however, 1 mg/mL of TA caused irreversible damage to cell morphology and viability. An interval > three weeks was needed to safely re-administer TA. These findings may help determine the appropriate dose and interval for TA injection therapy.Cite this article: Bone Joint Res 2014;3:328–34.

Atrophy with fatty degeneration is often seen in rotator cuff muscles with torn tendons. PRP has been reported to enhance tissue repair processes after tendon ruptures. However, the effect of PRP on atrophy and fatty degeneration of the muscle is not yet known. The aim of this study is to examine the effect of PRP on degeneration change of rotator cuff muscles in vitro and in vivo. A murine myogenic cell line and a rat rotator cuff tear model were used in this study and PRP was administrated into subacromial space which is widely used in clinical practice. In in vitro study, administration of PRP to C2C12 cells stimulated cell proliferation while inhibited both myogenic and adipogenic differentiation. In in vivo study, administration of PRP suppressed Oil Red-O positive lipid droplet formation. The expression of adipogenic genes was also decreased by PRP administration. In conclusion, PRP promoted proliferation of myoblast cells, while inhibiting adipogenic differentiation of myoblast cells and suppressing fatty degeneration change in rat torn rotator cuff muscles. Further investigations are needed to determine the clinical applicability of the PRP. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1806-1815, 2017.