Browsing by Subject "Tendinopathy"
Now showing 1 - 10 of 10
Results Per Page
Sort Options
- PublicationOpen AccessAnti-inflammatory and anti-catabolic effects of TENDOACTIVE® on human tenocytes in vitro(F. Hernández y J.F. Madrid. Murcia: Universidad de Murcia, Departamento de Biología Celular e Histología., 2011) Shakibaei, Mehdi; Buhrmann, C.; Mobasheri, A.Tendons have a limited capacity for self-repair due to the low density and mitotic activity of tenocytes. Pro-inflammatory cytokines such as interleukin-1ß (IL-1ß) have been identified as the main initiators of tendinopathies, stimulating inflammation, apoptosis and extracellular matrix (ECM) degradation. The aim of this study was to evaluate the potential of Tendoactive®, a newly developed proprietary nutraceutical formulation that includes mucopolysaccharides, collagen and vitamin C, in an in vitro model of tendon inflammation. The effects of Tendoactive® were studied in primary cultures of human tenocytes treated with IL-1ß for up to 72 h. Expression of collagen type I, integrin ß1, cyclo-oxygenase-2 (COX-2), caspase-3 and matrix metalloproteinase-1 (MMP-1) was monitored by western blotting. The effects of Tendoactive® on the expression, phosphorylation and nuclear translocation of protein components of the NF-κB system were studied by western blotting and immunofluorescence respectively. Treatment of tenocytes with Tendoactive® suppressed IL-1ß-induced NF-κB activation and p65 nuclear translocation. These events correlated with down-regulation of NF-κB targets including COX-2, MMP-1 and activated caspase-3. Tendoactive® also reversed the IL-1ß-induced down-regulation of collagen type I and ß1-integrin receptor expression. These results indicate that Tendoactive® has nutraceutical potential as an anti-inflammatory agent for treating tendinopathy through suppression of NF-κB mediated IL-1ß catabolic signalling pathways in tenocytes.
- PublicationOpen AccessImmunohistochemical and in situ hybridization observations favor a local catecholamine production in the human Achilles tendon(Murcia : F. Hernández, 2008) Bjur, Dennis; Danielson, Patrik; Alfredson, Hàkan; Forsgren, StureResults of recent studies using immunohistochemistry show evidence of an occurrence of catecholamine production in the cells (tenocytes) of patellar tendons exhibiting tendinopathy (tendinosis). In the present study, antibodies against the catecholaminesynthesizing enzyme tyrosine hydroxylase (TH) and a1- adrenoreceptors were applied to sections of specimens of normal and tendinosis Achilles tendons. In situ hybridization using a probe detecting human TH mRNA was also utilized. It was found that sympathetic innervation was very scarce. On the other hand, there were distinct a1-adrenoreceptor immunoreactions in blood vessel walls. Interestingly, tenocytes, particularly from tendinosis samples in which the tenocytes showed an abnormal shape (not the typical slender appearance), displayed TH immunoreactions and reactions for TH mRNA. Of further interest was the finding of a1- adrenoreceptor immunoreactions in tenocytes. The observations show not only evidence of local catecholamine production at the protein level, which was the case in recent studies for the patellar tendon, but also at the mRNA level. The observations suggest that the tenocytes, especially those with disfigured appearances in tendinosis, can produce catecholamines and also that they can respond to sympathetic transmitters. This is of interest as adrenergic stimulation in other parts of the body is known to induce degenerative/apoptotic and proliferative events, features which are seen in Achilles tendinosis. These observations are completely new findings concerning the human Achilles tendon. It is likely that locally produced catecholamines and the occurrence of autocrine/paracrine effects of these substances are of great relevance during the process of tendinosis.
- PublicationOpen AccessIn situ hybridization studies favouring the occurrence of a local production of BDNF in the human Achilles tendon(F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2012) Bagge, Johan; Danielson, Patrik; Forsgren, StureBrain derived neurotrophic factor (BDNF) is a multipotent neurotrophin known for its growth-influencing and apoptosis-modulating functions, as well as for its function to interact with neurotransmitters/neuromodulators. BDNF is reported to be mainly produced in the brain. BDNF can be absorbed into peripheral tissue from the blood stream. Expression of this neurotrophin at the protein level, as well as of the neurotrophin receptor p75, has been previously shown for the principal cells (tenocytes) of the Achilles tendon. However, there is no proof at the mRNA level that BDNF is produced by the tenocytes. As the Achilles tendon tenocytes show “neuronal-like” characteristics, in the form of expressions favouring synthesis of several neuromodulators/neurotransmitters, and as BDNF especially is produced in neurons, it is of interest to confirm this. In the present study, therefore, in situ hybridization for demonstration of BDNF mRNA was performed on biopsies from Achilles tendons of patients with tendinosis and pain-free non-tendinosis individuals. The results showed that the tenocytes of both groups exhibited BDNF mRNA reactions. These observations indeed favour the idea that BDNF is produced by tenocytes in the human Achilles tendon, why Achilles tendon tissue is a tissue in which BDNF can be locally produced. BDNF can have modulatory functions for the tenocytes, including apoptosis-modifying effects via actions on the p75 receptor and interactive effects with neurotransmitters/neuromodulators produced in these cells. This possibility should be further studied for Achilles tendon tissue
- PublicationOpen AccessInfrared thermography, intratendon vascular resistance and echotexture in athletes with patellar tendinopathy: a cross-sectional study(SAGE Publications, 2023-03) Molina Payá, Francisco J.; Ríos Díaz, José; Carrasco Martínez, Francisco; Martínez Payá, Jacinto Javier; FisioterapiaBackground: Ultrasonographic signs of tendinopathies are an increase in thickness, loss of alignment in collagen fibers and the presence of neovascularization. Nevertheless, analysis of intratendinous vascular resistance (IVR) can be more useful for understanding the physiological state of the tissue. Objective: To show thermal, echotextural and Doppler signal differences in athletes with patellar tendinopathy and controls. Methods: Twenty-six athletes with patellar tendinopathy (PT) participants (30.1 yrs; SD= 9.0 yrs) and 27 asymptomatic athletes (23.3 yrs; SD= 5.38 yrs) were evaluated with thermographic and Doppler ultrasonography (DS). Area of Doppler signals (DS), echotextural parameters (echointensity and echovariation) and IVR were determined by image analysis. The statistical analysis was performed by Bayesian methods and the results were showed by Bayes Factor (BF10: probability of alternative hypothesis over null hypothesis), and Credibility intervals (CrI) of the effect. Results: The absolute differences of temperature (TD) were clearly greater (BF10= 19) in the tendinopathy group (patients) than in controls. Regarding temperature differences between the affected and healthy limb, strong evidence was found (BF10= 14) for a higher temperature (effect= 0.53 ºC; 95% CrI=0.15 to 0.95 ºC) and very strong for reduced IVR compared (BF10= 71) (effect= -0.67; 95% CrI=- 1.10 to -0.25). The differences in area of DS (BF10= 266) and EV (BF10= 266) were higher in tendinopathy group. TD showed a moderate positive correlation with VISA-P scores (tau-B=.29; 95% CrI=.04 to .51) and strong correlation with IVR (r=-.553; 95%CrI=-.75 to -.18). Conclusion: Athletes with patellar tendinopathy showed a more pronounced thermal difference, a larger area of Doppler signal, a lower IVR and a moderately higher echovariaton than controls. The correlation between temperature changes and IVR might be related with the coexistence of degenerative and inflammatory process in PT.
- PublicationOpen AccessLocalization of advanced glycation end-products and their receptor in tendinopathic lesions(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2024) Asomugha, Eva; Cho, Young; Paudel, Sharada; Guo, Yi; Schon, Lew; Zhang, ZijunThis study was designed to investigate the accumulation of advanced glycation end-products (AGEs) and the expression of the receptor of AGEs (RAGE) in tendinopathic tissues. In this study, tendinopathic posterior tibial tendons (PTT) were collected from patients (n=6). Redundant autografts of flexor digitorum longus tendon (FDL; n=3) were used for controls. The control and tendinopathic tendon tissues were used for extraction of proteins for western blot and sectioned for histology and immunohisto-chemistry. Tendinopathy of the PTT was confirmed histologically by the presentation of disorderly collagen fibers, high cellularity and increased vascularity. By immunohistochemistry, heterogeneous accumulation of AGEs was detected on the PTT sections and concentrated in areas, where collagen fibers were disorderly and tangled. In the PTT, roundish tenocytes were also AGEs-positive. In contrast, AGEs were diffuse, lightly stained in the FDL. A greater number of tenocytes within the tendinopathic lesions in the PTT were RAGE positive, compared to the tenocytes in the FDL. Western blot confirmed the presence of AGEs and RAGE in both tendinopathic PTT and control FDL but their band densities were not significantly different. The spatial relation of the accumulated AGEs and RAGE- positive tenocytes within the tendinopathic lesions indicates their involvement in the molecular pathology of tendinopathy.
- PublicationOpen AccessMatrix metalloproteinase-1 (MMP-1) and (MMP-8) gene polymorphisms promote increase and remodeling of the collagen III and V in posterior tibial tendinopathy(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Diniz Fernandes, Tulio; Godoy Santos, Alexandre Leme; Santos, Maria Cristina; Pontin, Pedro; Alves Pereira, Caio Augusto; Justi Jardim, Yuri; Pereira Velosa, Ana Paula; Maffulli, Nicola; Teodoro, Walcy Rosolia; Capelozzi, Vera LuizaPosterior tibial tendinopathy (PTT) can lead to acquired flatfoot in adults. Many patients develop PTT without any identifiable risk factors. Molecular changes in extracellular matrix (ECM) and matrix metalloproteinase (MMP) polymorphism may influence the risk of developing PTT. We aim to investigate the association between matrix metalloproteinase-1 (MMP1) and (MMP-8) gene polymorphisms with changes in collagen I, III and V in PTT. A case-control study with 22 patients and 5 controls was performed. The MMP-1 (2G/2G) and MMP-8 (T/T) genotypes were determined by PCR-restriction fragment length polymorphism. Tendon specimens were evaluated by a histologic semiquantitative score, immunofluorescence and histomorphometry for collagen I, III and V. Tendon specimens from PTT demonstrated marked distortion of the architecture with necrosis, large basophilic areas with disruption of the normal linear orientation of collagen bundles, infiltration of inflammatory cells, dystrophic calcification and ossification. Under immunofluorescence, PTT tendon specimens showed weak green fluorescence and diffuse distribution of collagen I fibers, but strong fluorescence of collagen III and V. The collagen I fibers were significantly decreased whereas an increase of collagen III and V were found in PTT compared to control groups. In addition, PTT group presented a significant association with MMP-1 and MMP-8 gene polymorphisms. Patients with PTT matrix metalloproteinase-1 (MMP-1) and (MMP-8) gene polymorphisms presented an increase of the collagen III and V ratio, suggesting that the higher proportion in degenerated tendons could contribute to a decrease in the mechanical resistance of the tissue. Still, functional and association studies are needed to elucidate evident roles of MMPs in PTT.
- ItemOpen AccessRecent progress in macrophage- mediated tendon injury and healing(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2026) Yining Zhang; Yanzhao Dong; Xiaodi Zou; Ahmad Alhaskawi; Fangyu Yi; Sohaib Hasan Abdullah Ezzi; Vishnu Goutham Kota; Mohamed Hasan Abdulla Hasan Abdulla; Haiying Zhou; Alenikova Olga; Sahar Ahmed Abdalbary; Jinhui Liang; Hui Lu; Weijie Zhou; Biología Celular e HistologíaRecently, the role of macrophages in tendon repair has received increased attention. These cells are versatile, playing multiple roles, such as defending the host, engulfing debris, producing growth factors, and releasing substances that can both promote and alleviate inflammation. Within the scope of tendon repair and tendinopathy resolution, macrophages are essential contributors. However, the current understanding of macrophage involvement in tendon healing remains limited. Hence, understanding macrophages' impact on tendon healing is of considerable importance for devising innovative treatment approaches. It is crucial to examine the precise role that macrophages play in tendon recovery, as it provides new understanding that can propel both research and the development of therapeutic methods aimed at enhancing tendon recovery moving forward
- PublicationEmbargoReliability of a New Semi-automatic Image Analysis Method for Evaluating the Doppler Signal and Intratendinous Vascular Resistance in Patellar Tendinopathy(2021-12) Martínez Payá, Jacinto Javier; Carrasco Martínez, Francisco; Ríos Díaz, José; Molina Payá, Francisco J.; FisioterapiaAbstract The aim of this study was to determine the intra- and inter-rater reliability of a new semi-automatic image analysis method for quantification of the shape of the Doppler signal and the intratendinous vascular resistance in patellar tendinopathy. Thirty athletes (27.4 y, standard deviation = 8.57 y) with patellar intratendinous vascularity were included in a cross-sectional study (42 tendons analyzed). The intratendinous blood flow was assessed with power Doppler and ImageJ (Version 1.50b, National Institutes of Health, Bethesda, MD, USA) quantification software over a manually selected region of interest. Two blinded observers performed the analysis of the Doppler signal (vascular resistance) and shape descriptors (number of signals, pixel intensity, area, perimeter, major diameter, minor diameter, circularity and solidity). The intraclass correlation coefficient (ICC) was calculated, and the Bland-Altman mean of differences (MoD) and 95% limits of agreement (LoA) were determined. Also, small real differences (SRDs) and the standard error of measurement (SEM) were calculated. Intra-rater reliability was at a maximum for area (ICC = 0.999, 95% confidence interval [CI] = 0.998-0.999) and at a minimum for solidity (ICC = 0.782, 95% CI: 0.682-0.853). The MoD and 95% LoA were very low, and the relative SRD and SEM were below 5.3% and 2%, respectively. The inter-rater reliability was the maximum for area (ICC = 0.993, 95% CI = 0.989-0.996) and the minimum for circularity (ICC = 0.73; 95% CI=0.611-0.817). The MoD and 95% LoA were low, with the SRD and SEM below 6% and 2.2%. The proposed quantitative method for studying the intratendinous Doppler signal in the patellar tendon is reliable and reproducible.
- PublicationOpen AccessTendinopathy and its treatment with platelet-rich plasma (PRP)(F. Hernández y Juan F. Madrid. Universidad de Murcia. Departamento de Biología Celular e Histología, 2013) Jiang, Dapeng; Wang, James H-C.This article has two goals. First, it reviews studies on tendinopathy in the literature while highlighting the following points: a) tendinopathy refers to a spectrum of tendon disorders with multiple facets of "tissue phenotypes," and b) mechanical loading is a major factor that contributes to the development of tendinopathy by inducing the aberrant differentiation of tendon stem/progenitor cells into non-tenocyte cell lineages. Second, the current treatments of tendinopathy with platelet-rich plasma (PRP) are briefly described, issues related to PRP treatment in clinics are highlighted, and the needs for basic science research on clinical usage of PRP for tendinopathy treatment are discussed.
- PublicationOpen AccessUnexpected presence of the neurotrophins NGF and BDNF and the neurotrophin receptor p75 in the tendon cells of the human Achilles tendon(Murcia : F. Hernández, 2009) Bagge, Johan; Lorentzon, Ronny; Alfredson, Hàkan; Forsgren, StureNeurotrophins are substances that have been shown to be important in growth and remodelling phases in different types of tissue. There is no information concerning the possible occurrences of neurotrophins and their receptors in tendons. In this study, sections of both chronic painful (tendinosis) and pain-free (nontendinosis) human Achilles tendons were immunohistochemically stained with antibodies against the neurotrophins NGF and BDNF, and their receptors TrkA, TrkB and p75. There were marked immunoreactions for NGF and BDNF in the tendon cells (tenocytes) of both tendinosis and non-tendinosis specimens. The tenocytes were also reactive for the receptor p75, but not for the receptors TrkA and TrkB. In addition, p75 immunoreactions were seen in nerve fascicles and in the walls of arterioles. This is the first study to identify neurotrophins in the tenocytes of human tendon. It is clear from this study that the local cells of tendons are sources of neurotrophins. The neurotrophins may play an important role in the tendon through their interaction with the receptor p75 in the tenocytes. These interactions may regulate tropic modulatory, and apoptotic effects. In conclusion, the observations show a new concept concerning production and function of neurotrophins, namely in the tenocytes of tendons.