Perinatal hypoxic ischemic (HI) injury is a leading cause of long-term neurological complications in newborn babies. Matrix metalloproteinases (MMPs) are a family of endopeptidases that are capable of degrading the extracellular matrix (ECM) components. They are considered to be integral in many physiological processes. However, recently it has been demonstrated that the inappropriate activity of these proteases, particularly MMP-2 and 9, contribute to the pathogenesis of cerebral ischemia in the adult brain. Given that ECM disruption is frequently observed following injury to the developing brain, it is possible that MMPs play an important role in HI injury processes in the developing brain. Therefore, this thesis evaluated the hypothesis that MMP-2 and 9 participate in the pathophysiology of HI injury to the developing brain. Since ECM remodelling is a fundamental process during brain development it was important to first characterise the MMP-2 and 9 profiles in the normal developing forebrain. We demonstrated that MMP-2, which mainly was observed in cortical plate neurons, declined with age, thus indicating a potential role in the development and differentiation of the cortical plate. Conversely, MMP-9 was increased with age, particularly during active myelination, indicating that it may contribute in myelination. Secondly, we showed an upregulation of MMP-9 within the ischemic core during the early hours following HI injury, suggesting that MMP-9 may be involved in the development of delayed injury processes following hypoxic ischemia. On the contrary, MMP-2 was strongly upregulated during a later stage following injury surrounding the ischemic core possibly suggesting that it plays a role in wound repair processes. Thirdly, the profiles of tissue (tPA) and urokinase (uPA) plasminogen activators were characterised following HI injury since they are known to be major upstream activators of MMPs. uPA upregulation paralleled that of MMP-2 suggesting a function for uPA in wound repair processes following HI injury to the developing brain through activation of MMP-2. In contrast with uPA, tPA activity remained unaffected following injury at both ages. Finally, MMP-9 activity was inhibited using a very specific MMP-2/9 inhibitor, SB-3CT, to determine if the MMP-9 deficiency protects the developing brain from HI injury. The elevated MMP-9 activity following HI injury was attenuated by the SB-3CT treatment. Although SB-3CT failed to confer any significant neuroprotection, we recommend that further investigations are needed before discounting the role of MMP-9 during HI injury to the developing brain. In conclusion, we suggest that MMP-9 is induced following an insult to the developing brain potentially contributing to the delayed neuronal death whilst MMP-2 is involved in essential developmental, differentiation and wound repair processes.

Perinatal hypoxic ischemic (HI) injury is a leading cause of long-term neurological complications in newborn babies. Matrix metalloproteinases (MMPs) are a family of endopeptidases that are capable of degrading the extracellular matrix (ECM) components. They are considered to be integral in many physiological processes. However, recently it has been demonstrated that the inappropriate activity of these proteases, particularly MMP-2 and 9, contribute to the pathogenesis of cerebral ischemia in the adult brain. Given that ECM disruption is frequently observed following injury to the developing brain, it is possible that MMPs play an important role in HI injury processes in the developing brain. Therefore, this thesis evaluated the hypothesis that MMP-2 and 9 participate in the pathophysiology of HI injury to the developing brain. Since ECM remodelling is a fundamental process during brain development it was important to first characterise the MMP-2 and 9 profiles in the normal developing forebrain. We demonstrated that MMP-2, which mainly was observed in cortical plate neurons, declined with age, thus indicating a potential role in the development and differentiation of the cortical plate. Conversely, MMP-9 was increased with age, particularly during active myelination, indicating that it may contribute in myelination. Secondly, we showed an upregulation of MMP-9 within the ischemic core during the early hours following HI injury, suggesting that MMP-9 may be involved in the development of delayed injury processes following hypoxic ischemia. On the contrary, MMP-2 was strongly upregulated during a later stage following injury surrounding the ischemic core possibly suggesting that it plays a role in wound repair processes. Thirdly, the profiles of tissue (tPA) and urokinase (uPA) plasminogen activators were characterised following HI injury since they are known to be major upstream activators of MMPs. uPA upregulation paralleled that of MMP-2 suggesting a function for uPA in wound repair processes following HI injury to the developing brain through activation of MMP-2. In contrast with uPA, tPA activity remained unaffected following injury at both ages. Finally, MMP-9 activity was inhibited using a very specific MMP-2/9 inhibitor, SB-3CT, to determine if the MMP-9 deficiency protects the developing brain from HI injury. The elevated MMP-9 activity following HI injury was attenuated by the SB-3CT treatment. Although SB-3CT failed to confer any significant neuroprotection, we recommend that further investigations are needed before discounting the role of MMP-9 during HI injury to the developing brain. In conclusion, we suggest that MMP-9 is induced following an insult to the developing brain potentially contributing to the delayed neuronal death whilst MMP-2 is involved in essential developmental, differentiation and wound repair processes.

Η HARP (Heparin Affin Regulatory Peptide) είναι ένας αυξητικός παράγοντας με Μ.Β. 18 kDa που ανήκει στην οικογένεια των αυξητικών παραγόντων που έχουν συγγένεια με την ηπαρίνη. Eμπλέκεται στην ανάπτυξη των νευριτών, την επούλωση πληγών και φαίνεται να παίζει σημαντικό επαγωγικό ρόλο στις διαδικασίες της ογκογένεσης, καθώς επάγει την αγγειογένεση και εμφανίζεται σε υψηλές συγκεντρώσεις τόσο σε καρκινικούς ιστούς, όσο και σε κυτταρικές σειρές καρκινικών κυττάρων. Στο πλαίσιο μελέτης της σχέσης δομής/δράσης του αυξητικού αυτού παράγοντα, χρησιμοποιούνται τόσο συνθετικά πεπτίδια, όσο και ανασυνδυασμένες τροποποιημένες μορφές του αυξητικού αυτού παράγοντα. Σε φυσιολογικές συνθήκες, η εκκρινόμμενη HARP πέπτεται από ένζυμα του κυτταρικού μικροπεριβάλλοντος και προκύπτουν πεπτίδια που παρουσιάζουν βιολογικές δράσεις παρόμοιες ή και αντίθετες από αυτές της HARP. Φαίνεται λοιπόν πως η δράση του αυξητικού αυτού παράγοντα ρυθμίζεται τόσο στο επίπεδο βιοσύνθεσης και έκκρισης, όσο και από τη δράση ενζύμων του εξωκυττάριου χώρου. Στην παρούσα εργασία μελετήθηκε η δράση ενός συνθετικού πεπτιδίου το οποίο αντιστοιχεί στα αμινοξέα 65-97 που εντοπίζονται στην ΤSR περιοχή προς το καρβοξυτελικό άκρο της HARP. Με δεδομένο ότι τι πεπτίδιο αυτό εμφανίζει αντιαγγειογενετική δράση, πραγματοποιήθηκαν χρονοεξαρτώμενα και δοσοεξαρτώμενα πειράματα, με σκοπό τη μελέτη της δράσης του στον πολλαπλασιασμό, τη μετανάστευση και την επούλωση πληγών. Στο πλαίσιο αυτών των μελετών, ελέγξαμε τη δράση του στην έκφραση των μεταλλοπρωτεϊνασών ΜΜP-2 και ΜΜP-9, των αναστολέων τους ΤΙMP-1 και ΤΙMP-2 καθώς και του κολλαγόνου και της ελαστίνης σε πρωτογενείς καλλιέργειες ενδοθηλιακών κυττάρων από ομφάλιο λώρο (HUVEC cells). Τα αποτελέσματα έδειξαν πως το συνθετικό αυτό πεπτίδιο καταστέλλει τον πολλαπλασιασμό, την μετανάστευση αλλά και την επούλωση πλήγών των κυττάρων HUVEC με δοδοεξαρτώμενο και στατιστικώς σημαντικό τρόπο. Επιπλέον από τα πειράματά μας δεν παρατηρήθηκε μεταβολή στα πρωτεϊνικά επίπεδα έκφρασης των μεταλλοπρωτεϊνασών ΜΜP-2 και ΜΜP-9 καθώς και των αναστολέων τους ΤΙMP-1 και ΤΙMP-2. Ωστόσο, παρατηρήθηκε στατιστικώς σημαντική μεταβολή στα επίπεδα γονιδιακής έκφρασης των αναστολέων ΤΙMP-1 και ΤΙMP-2 όπως επίσης και της ελαστίνης και του κολλαγόνου IV. / Heparin affin regulatory peptide (HARP) is an 18-kDa secreted growth factor that has a high affinity for heparin and a potent role on tumor growth and angiogenesis. HARP was originally described as a neurite outgrowth promoting molecule, which appears to increases during recovery from injury and is thought to be involved in angiogenesis expression, playing a major role in the cell growth and differentiation that are associated with regeneration in several tissues. HARP is expressed in several human tumors and tumor cell lines and is also indicated in high serum levels of patients with different types of cancer. HARP contains two random coiled clusters of basic residues (N- and C-terminal) and two b-sheet domain. Each b-sheet domain contains a thrombospondin repeat I (TSR-I) motif, which have been suggested to be responsible for the interaction of HARP with heparin. Our project is based on C-TSR-I domain, corresponding to amino acids 65–97 of HARP peptide, respectively, required for the neurite outgrowth activity of HARP. In this study, we investigate the impact of C-TSR on basic biological functions of endothelial cells (HUVEC) such as proliferation, migration, the expression of MMP-2 and MMP-9 and their inhibitors (TIMP-1, TIMP-2) that contribute to the ECM remodeling. Time course and dose-response experiments revealed that CTSR reduces proliferation, migration and wound healing, without affecting the protein levels of MMP-2 and MMP-9 and their inhibitors (TIMP-1, TIMP-2). Moreover, CTSR inhibits the expression of TIMP-1 and TIMP-2 contributing to the ECM remodeling. Concluding, HARP could act as pro- or anti-angiogenic factor, depending on the system used and the cell microenvironment.

Made available in DSpace on 2016-06-02T20:18:12Z (GMT). No. of bitstreams: 1 2857.pdf: 11303199 bytes, checksum: e1e51cdf6acc5b01445639c49dd0e72d (MD5) Previous issue date: 2010-03-17 / Universidade Federal de Minas Gerais / Peripheral nerves are frequently target of traumatic injuries and their functional recovery is generally incomplete. The aim of the present study was to evaluate the effects of 660 or 780 nm low-level laser therapy (LLLT) GaAlAs using different energy densities (10, 60 and 120 J/cm2) on nerve sciatic recovery after severe (neurotmesis) or moderate (axonotmesis) injuries in rat. One hundred and twenty eight Wistar male rats (275g) were divided into 16 groups, and they were performed as follow: For axonotmesis: Normal (N); axonotmesis (CR); axonotmesis and 660 nm LLLT with 10 J/cm2 irradiation (CR660 10J); CR660 60J; CR660 120J; CR780 10J; CR780 60J; CR780 120J. For neurotmesis: N; neurotmesis (TT); TT660 10J; TT660 60J; TT660 120J; TT780 10J; TT780 60J; TT780 120J. The LLLT irradiation was performed using a fix potence of 40 mW and a spot area of 4 mm2. Nerves submitted to axonotmesis or neurotmesis were irradiated with LLLT daily during 10 consecutive days starting on the first post-operatory. However, neurotmesis groups received additionally one month of LLLT applied every other day. Tibialis anterior (TA) muscles and sciatic nerve were evaluated 28 (axonotmesis) and 84 (neurotmesis) after surgery. The follow analyses were performed: muscle fiber, axon, myelin and nerve fiber cross-sectional area (CSA); matrix metalloproteinases (MMP) 2 and 9 activities; sciatic functional index; S-100 immunofluorescence. Data were submitted to homogeneity and normality tests. Anova one-way followed by Tukey tests and Kruskal-Wallis followed by Newman-Keuls tests were performed when data was parametric or non-parametric, respectively. Significance level was set at 5%. The results of the present study showed that groups irradiated with 660 nm LLLT with 10 or 60 J/cm2, and 780 nm 10 or 120 J/cm2 showed normal values of nerve fiber and myelin CSA. The 660 nm LLLT, regardless the energy density used, accelerated muscle fiber recovery and increased the MMP-2 activity in nerve. Furthermore, it also decreased the MMP-9 and MMP-2 activities in nerves and muscles respectively. All axotomized animals recovery normal levels of function on the 28 day after surgery. Regarding neurotmesis groups, TT660 120J presented higher values of myelin and nerve fiber CSA compared to TT. Superior values of muscle fiber CSA were observed in TT660 60 e 120J e TT780 10J compared to TT. These LLLT parameters were also efficient to decrease MMP-2 activity in TA muscles. All groups submitted to neurotmesis did not recover normal function after 84 days of injury. Based on the proposed objective, it is possible to conclude that LLLT, considering specific protocols vi of application, recovered nerves effectively, avoided muscle fiber atrophy and acted on the muscle and nerve extracellular matrix remodeling via MMPs regulation. / O objetivo do estudo foi analisar a ação dos lasers de baixa intensidade (GaAlAs) com diferentes comprimentos de ondas (660 e 780 nm), em diferentes densidades de energia (10 J/cm², 60 J/cm² e 120 J/cm2) na regeneração do nervo ciático do rato após lesões moderadas (axoniotmese) e graves (neurotmese). Para tal, 128 ratos Wistar (275 g) foram divididos em 16 grupos: Para axoniotmese: Normal (N); axoniotmese (CR); axoniotmese irradiado com laser 660 nm com 10 J/cm2 (CR660 10J); CR660 60J; CR660 120J; CR780 10J; CR780 60J; CR780 120J. Para neurotmese: N; neurotmese (TT); TT660 10J; TT660 60J; TT660 120J; TT780 10J; TT780 60J; TT780 120J. A estimulação a laser foi realizada com potência fixa de 40 mW e área do feixe de 4,0 mm2. O laser foi aplicado durante 10 dias consecutivos, a partir do primeiro dia do pós-operatório nos nervos com axoniotmese e neurotmese. Entretanto, para os grupos neurotmese foi acrescido de mais um mês de aplicação em dias alternados. Os músculos tibiais anteriores (TA) e os nervos ciáticos foram avaliados após 28 (axoniotmese) e 84 dias (neurotmese) após a cirurgia. Para investigar a área de secção transversa (AST) das fibras musculares, axônios, mielina e fibra nervosa; número de fibras nervosas foi feita morfometria. A atividade das metaloproteinases de matriz (MMPs) 2 e 9 foi realizada para observar o remodelamento da matriz. O índice funcional do nervo ciático foi para avaliar a função. A imunoflorescência com anticorpo S-100 foi utilizada para a observar a bainha de mielina e células de Schwann. Os dados foram submetidos a testes de homogeneidade e normalidade. Os testes Anova one-way seguido por Tukey e Kruskal-Wallis seguido por Newman-Keuls foram usados em amostras paramétricas e não paramétricas, respectivamente. Um nível de significância de 5% foi adotado. Os resultados deste estudo mostram que os grupos axoniotmese irradiados com lasers 660 nm 10 e 60 J/cm2, 780 nm 10 e 120 J/cm2 apresentaram AST da fibra nervosa e da mielina semelhante aos valores normais. O laser 660 nm, independente da densidade de energia utilizada, acelerou a recuperação da atrofia muscular e aumentou a atividade da MMP-2 nos nervos ciáticos dos grupos axoniotmese. Ele também reduziu a atividade da MMP-9 nos nervos e da MMP-2 nos músculos. Todos os animais submetidos à axoniotmese recuperaram a função normal após 28 dias de lesão. Em relação aos grupos neurotmese, foram observados valores superiores de AST da bainha de mielina e de fibra nervosa no grupo TT660 120J comparado ao TT. Valores de AST das fibras musculares foram superiores ao TT nos grupos TT660 60 e 120J e TT780 10J. Estes parâmetros de laser também foram eficientes em promover a diminuição da atividade de MMP-2 nos músculos TA. Todos os grupos submetidos à neurotmese não recuperaram totalmente a função após 84 dias de lesão. Com base no objetivo proposto podemos concluir que a laserterapia, em determinados protocolos de aplicação, mostrou-se efetiva na recuperação do nervo, evitou a atrofia do muscular e atuou no remodelamento da matriz extracelular do músculo e do nervo periférico via regulação das MMPs.

Made available in DSpace on 2016-06-02T19:22:03Z (GMT). No. of bitstreams: 1 2425.pdf: 1867201 bytes, checksum: 5e3f6810f116a13f8397936acba4c138 (MD5) Previous issue date: 2009-06-09 / Universidade Federal de Sao Carlos / As metaloproteases de matriz (MMPs) são cruciais para manutenção do tecido saudável. O objetivo deste estudo foi investigar a atividade da MMP-2 nos músculos gastrocnêmio, sóleo, tibial anterior (TA) e extensor longo dos dedos (EDL) após treinamento de força em ratas ovariectomizadas. Ratas Wistar adultas foram alocadas nos grupos: sedentário (Sed-Intacto); sedentário ovariectomizado (Sed-Ovx); sedentário pseudo-ovariectomizado (Sed-Pseudo); exercício agudo (AgudoEx-Intacto); exercício agudo ovariectomizado (AgudoEx-Ovx); treinamento de força (CrônicoEx-Intacto) e treinamento de força ovariectomizado (CrônicoEx-Ovx) (n= 10 por grupo). Foi utilizado um treinamento de força de 12 semanas no qual os animais escalaram uma escada vertical de 1,1-m com pesos presos as suas caudas. As sessões foram realizadas com intervalo de três dias, 4-9 escaladas e 8-12 movimentos dinâmicos por escalada. A atividade da MMP-2 foi analisada por zimografia. Houve uma maior atividade da MMP-2 nos grupos CrônicoEx-Intacto e CrônicoEx-Ovx e menor atividade no AgudoEx-Ovx comparado com o grupo Sed-Intacto no sóleo (p≤0,05). Os grupos Sed-Ovx e CrônicoEx-Ovx apresentaram menor atividade da MMP-2 comparado com o grupo Sed-Intacto no TA. Houve maior atividade da MMP-2 no AgudoEx-Intacto e AgudoEx-Ovx comparado com Sed-Intacto e Sed-Ovx no TA, respectivamente (p≤0,05). Nos músculos TA e EDL o treinamento aumentou a atividade da MMP-2 comparado com o grupo Sed-Intacto. Não foram observadas alterações estatisticamente significativas para o músculo gastrocnêmio. O treinamento de força aumenta a atividade da MMP-2 nos músculos sóleo, TA e EDL, o que pode ser importante para o remodelamento muscular. A ovariectomia reduz a atividade da MMP-2 no TA e EDL, possivelmente comprometendo a função muscular.

Abstract Breast carcinoma is a heterogeneous disease with a prognosis that varies from excellent to very poor. Traditional tumour parameters and biological factors that are also predictive for treatment response are used in determining breast carcinoma prognosis and selecting appropriate treatment. Gelatinases MMP-2 and MMP-9 have been shown to associate with tumour progression. Their tissue inhibitors TIMP-1 and -2 are multifunctional molecules that have been suggested as prognostic markers in some previous reports. In the present work, the expression and prognostic value of gelatinases MMP-2 and MMP-9 and their tissue inhibitors TIMP-1 and -2 were assessed in primary breast carcinoma. The material consisted of a total of 416 patients. Tissue expression of TIMP-1 and -2 was analysed in a population of 203 patients using immunohistochemistry. Circulating gelatinases and their inhibitors were studied using ELISA in two different populations of 71 at preoperative state and 213 patients at pre- and postoperative state. High expression of TIMP-1 immunoreactive protein positively correlated with high histological grade of the tumour and associated with aggressive disease course in grade 2–3 subpopulation. High preoperative plasma TIMP-1 was prognostic for relapse in a modern patient series after a median follow-up time of 18 months. TIMP-1 as a continuous variable was prognostic in Cox regression univariate analysis, and was an independent prognostic variable superior to nodal status in multivariate analysis. High preoperative serum TIMP-1 was an independent prognostic variable for poor disease-specific survival, and TIMP-1 was found to maintain its prognostic value when assessed independently with different ELISA analyses, and was not very sensitive for preanalytical conditions. In addition, low circulating preoperative serum MMP-2 was observed to associate with high stage and positive nodal status in breast carcinoma. These results indicate that circulating TIMP-1 may be a potential new marker of worsened prognosis in breast carcinoma, although careful validation of assay platforms and identification of the sources of physiological variation are needed before it can be adopted into clinical decision-making.

Yes / (1) Abdominal aortic aneurysm (AAA) is a silent, progressive disease with significant mortality from rupture. Whilst screening programmes are now able to detect this pathology early in its development, no therapeutic intervention has yet been identified to halt or retard aortic expansion. The inability to obtain aortic tissue from humans at early stages has created a necessity for laboratory models, yet it is essential to create a timeline of events from EARLY to END stage AAA progression. (2) We used a previously validated ex vivo porcine bioreactor model pre-treated with protease enzyme to create "aneurysm" tissue. Mechanical properties, histological changes in the intact vessel wall, and phenotype/function of vascular smooth muscle cells (SMC) cultured from the same vessels were investigated. (3) The principal finding was significant hyperproliferation of SMC from EARLY stage vessels, but without obvious histological or SMC aberrancies. END stage tissue exhibited histological loss of α-smooth muscle actin and elastin; mechanical impairment; and, in SMC, multiple indications of senescence. (4) Aortic SMC may offer a therapeutic target for intervention, although detailed studies incorporating intervening time points between EARLY and END stage are required. Such investigations may reveal mechanisms of SMC dysfunction in AAA development and hence a therapeutic window during which SMC differentiation could be preserved or reinstated. / This research was funded in part by The Leeds Teaching Hospitals Charitable Foundation (R11/8002). E.R.C. was supported by a PhD studentship from the Engineering and Physical Sciences Research Council (EPSRC; EP/F500513/1). R.J.H. was the recipient of an Intercalated Batchelor of Science Degree in Science award from the Royal College of Surgeons of England. M.A.B.(FS/18/12/33270 and FS/12/54/29671), K.I.B. (FS/12/26/29395), and K.J.G. (FS/11/91/29090) were supported by BHF Clinical Research Training Fellowships.

The aim of this study is to analyse a genetic and proteomic aspects that could play an important role in development of chosen cardiovascular disease. Matrix metalloproteinases are enzymes that contribute strongly to the degradation of extracellular matrix components. In this study the serological levels of MMP-2 and MMP-9 were investigated using immunological testing in patients with aortic valve disease and in patients with myocardial infarction. Significantly higher levels of MMP-2 and MMP-9 were determined in both above mentioned groups of patients. Association of serum levels of MMP-2 and MMP-9 and development of concomitant aortic dilatation was not confirmed in patients with aortic valve disease. Changes in serum levels within 24 hours and after 6 months post myocardial infarction were characterized. About 10 % of patients operated for aortic valve disease suffer simultaneously from ascending aortic dilatation. The current study did not reveal any significant genetic variation in TGFBR2 gene and in chosen exons of FBN1 gene in these patients. Further genetic research is needed to identify the cause of the pathology in aortic wall. Gene expression of selected genes was measured by microarray screening in patients with myocardial infarction. These genes were related to MMPs and did not show...

Made available in DSpace on 2016-06-02T20:19:08Z (GMT). No. of bitstreams: 1 1843.pdf: 1192914 bytes, checksum: 124690357d5fd2c475721de4dd0a5c76 (MD5) Previous issue date: 2008-02-27 / Financiadora de Estudos e Projetos / As lesões musculares são bastante comuns na prática esportiva e na reabilitação ortopédica. A terapia laser de baixa intensidade (TBLI) apresenta bons resultados no tratamento de diferentes afecções que acometem o tecido muscular esquelético, entretanto a fluência utilizada neste tratamento ainda é controversa. Este estudo tem como objetivo verificar os efeitos de diferentes fluências do laser de λ= 830nm no processo de regeneração muscular. Foram utilizados ratos machos Wistar, distribuídos em 8 grupos de 7 animais cada: grupo controle (C); grupos em que os músculos tibial anterior direito (TAD) foram apenas irradiados com laser diodo (λ= 830nm) com fluência de 4J/cm 2 (4J), 8J/cm 2 (8J) e 16J/cm2 (16J); grupo lesão (CL), no qual o músculo foi submetidos à criolesão; grupos em que os músculos TAD foram submetidos à criolesão e tratados com laser diodo (λ= 830nm) com fluência de 4J/cm 2 (L6J), 8J/cm 2 (L8J), 16J/cm2 (L16J). A irradiação teve início 24horas após a lesão por 5 dias consecutivos de forma pontual, sobre a área de lesão. No sexto dia após a lesão, os animais foram eutanaziados. O sangue foi coletado para avaliação dos níveis plasmáticos de NOx-, através da técnica de Griess. A avaliação muscular contou com análises histológicas da área de lesão (Hematolina e Eosina e Fosfatase Ácida). Além disso, a atividadade da COX-2 foi analisada pelas técnicas de Biotin Switch e a atividade e expressão protéica de MMP-2 por técnica de Zimografia e Western Blotting, respectivamente. Os resultados mostraram que houve uma diminuição da área de lesão conforme aumento da fluência do laser (8J/cm2 e 16J/cm2); um aumento nos níveis plasmáticos de NOx- em todos grupos lesados e uma diminuição apenas no grupo L16J em relação aos grupos lesados; a COX-2 foi ativada apenas nos grupos CL e L4J; a atividade da MMP-2 aumentou em todos grupos lesados e a expressão protéica aumentou nos grupos L8J e L16J. Conjuntamente os resultados permitem concluir que as fluências de 8J/cm2 e 16J/cm2 foram as que apresentaram um melhor desempenho na TLBI nos processos que envolvem regeneração do músculo esquelético de ratos. Este estudo trouxe dados importantes para o uso clínico, pois confrontou variáveis importantes como o comportamento de diferentes fluências no processo de regeneração muscular, proporcionando verificar um protocolo de aplicação mais seguro e eficaz.

Yes / Studies have been conducted to highlight the anti-inflammatory and immunosuppressive properties of synthetic cannabinoids as well as their potential for cartilage repair. Various wound healing techniques can be used to investigate the mechanisms of chondrocyte repair in monolayers or three dimensional tissues constructs. In this work the effect of WIN55, 212-2 (WIN-2) on nitric oxide (NO) and matrix metalloproteinase-2 (MMP-2) expressed by wounded chondrocyte monolayers was investigated. Moreover, expression of collagen type-I and type-II, fibronectin and S100 proteins were detected using immunofluorescence and quantitatively verified using ELISA based techniques following treatment with 1 μM and 2 μM of WIN-2. Treating chondrocytes with 1 μM of WIN-2 significantly increased expression of collagen type-II, fibronectin and S100, and significantly reduced collagen type-I expressions as compared to the control groups. On the other hand, both concentrations of WIN-2 significantly reduced the expression of the inflammation markers NO and MMP-2 in a dose dependent manner. These findings highlight the potential use of the synthetic cannabinoids for improving cartilage healing properties as well as acting as an anti-inflammatory agent which could be used to enhance tissue engineering protocols aimed at cartilage repair.