Inhibition of diabetes mellitus-induced knee joint injury in rats by a combination of metformin and captopril / Inhibición de la lesión de la articulación de la rodilla inducida por diabetes mellitus en ratas mediante una combinación de metformina y captopril

SUMMARY: Osteoarthritis (OA) is an inflammatory disease that damages the joints and affects millions of people worldwide. The potential inhibitory effects of the antidiabetic drug metformin combined with captopril, the angiotensin-converting enzyme inhibitor, on diabetes-induced damage to the knee joint articular cartilage associated with the inhibition of glycemia, dyslipidemia, and inflammation has not been investigated before. Therefore, we induced diabetes in rats using high carbohydrate and fat diets and a single injection of streptozotocin (50 mg/kg). The protective group of rats was pre-treated with combined daily doses of metformin (Met; 200 mg/kg body weight) and captopril (Cap; 150 mg/kg body weight) for 14 days before diabetic induction and continued on metformin and resveratrol until the end of the experiment at week 12. Harvested tissues obtained from knee joints were prepared for basic histology staining with haematoxylin and eosin (H&E) and examined under light microscopy. Representative H&E images showed that OA was developed in the diabetic rats as demonstrated by a profound damage to the knee joints such as irregular eroded and a sharp decrease in the thickness of the articular cartilage surface and abnormal remodeling of the subchondral bone that were substantially ameliorated by Met+Cap. Met+Cap also significantly (p< 0.05) reduced blood levels of glucose, glycated hemoglobin (HbA1c), dyslipidemia, and the inflammatory biomarkers, high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-α) induced by diabetes. In addition, a significant (p≤ 0.0014) correlation between the articular cartilage thickness and the blood levels of glucose, HbA1c, triglyceride (TG), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein- cholesterol (HDL-C), and hs-CRP were observed. Thus, we demonstrate that Met+Cap effectively protect the knee joint against injuries induced secondary to diabetes in rats, possibly due to the inhibition of glycemia, dyslipidemia, and biomarkers of inflammation.

RESUMEN: La osteoartritis (OA) es una enfermedad inflamatoria que daña las articulaciones y afecta a millones de per- sonas en todo el mundo. No se han investigado los posibles efectos inhibidores del fármaco antidiabético metformina combinado con captopril, el inhibidor de la enzima convertidora de angiotensina, sobre el daño inducido por la diabetes en el cartílago articular de la articulación de la rodilla asociado con la inhibición de la glucemia, dislipidemia e inflamación. En este estudio fue inducida la diabetes en ratas con dietas altas en carbohidratos y grasas y una sola inyección de estreptozotocina (50 mg / kg). El grupo protector de ratas se pretrató con dosis diarias combinadas de metformina (Met; 200 mg / kg de peso corporal) y captopril (Cap; 150 mg / kg de peso corporal) durante 14 días antes de la inducción diabética. El tratamiento se continuó con metformina y resveratrol hasta el final del experimento en la semana 12. Los tejidos obtenidos de las articulaciones de la rodilla se prepararon para la tinción de histología básica con hematoxilina y eosina (H&E) y se examinaron con microscopía óptica. Imágenes representativas de H&E mostraron que la OA se desarrolló en las ratas diabéticas, como lo evidencia un daño profundo en las articulaciones de la rodilla, como la erosión irregular y una fuerte disminución en el grosor de la superficie del cartílago articular y remodelación anor- mal del hueso subcondral que fueron mejorados sustancialmente por Met + Cap. Met + Cap. También redujo significativamente (p <0.05) los niveles sanguíneos de glucosa, hemoglobina glicosilada (HbA1c), dislipidemia y los biomarcadores inflamatorios, proteína C reactiva de alta sensibilidad (hs-CRP), interleucina-6 (IL-6), y factor de necrosis tumoral alfa (TNF-α) inducido por diabetes. Además, una correlación significativa (p≤ 0,0014) entre el grosor del cartílago articular y los niveles sanguíneos de glucosa, HbA1c, triglicéridos (TG), lipoproteínas-colesterol de baja densidad (LDL- C), lipoproteínas de alta densidad-colesterol (HDL-C) ) y hs-CRP. Así, demostramos que Met + Cap protege eficazmente la articulación de la rodilla contra lesiones inducidas por diabetes en ratas, posiblemente debido a la inhibición de la glicemia, dislipidemia y biomarcadores de inflamación.

Comparison between two different experimental models of osteoarthritis in rabbits. Intra-articular collagenase injection and anterior cruciate ligament transection

ABSTRACT PURPOSE: To compare two different experimental models of osteoarthritis in rabbits: intra-articular collagenase injection and anterior cruciate ligament transection. METHODS: Ten adult rabbits were randomly divided in two groups: COLL (collagenase group) and ACLT (anterior cruciate ligament transection). The COLL group was treated with 0.5 ml collagenase solution (2mg collagenase/0.5 ml sterile PBS), and the ACTL group was subjected to anterior cruciate ligament. After six and twelve weeks, respectively, the animals in the COLL and ACTL groups were euthanized. The gross appearance and histological examinations conducted in the cartilage articular surface was blindly scored according to the criteria developed by Yoshimi et al. (1994) and Mankin et al. (1971), respectively. RESULTS: The gross morphologic observation, macroscopic score and histological examinations have demonstrated that the ACTL group presented the highest scores, and lesions more severe than those in the COLL group. CONCLUSIONS: Both methods, anterior cruciate ligament transection and collagenase, applied to the stifle joint of the rabbits have effectively induced degenerative changes in the cartilage tissue, through statistically significant analysis (p≤0.05). The ACTL method has presented more severe lesions.

Grape seed proanthocyanidin extract ameliorates monosodium iodoacetate-induced osteoarthritis

Osteoarthritis (OA) is an age-related joint disease that is characterized by degeneration of articular cartilage and chronic pain. Oxidative stress is considered one of the pathophysiological factors in the progression of OA. We investigated the effects of grape seed proanthocyanidin extract (GSPE), which is an antioxidant, on monosodium iodoacetate (MIA)-induced arthritis of the knee joint of rat, which is an animal model of human OA. GSPE (100 mg/kg or 300 mg/kg) or saline was given orally three times per week for 4 weeks after the MIA injection. Pain was measured using the paw withdrawal latency (PWL), the paw withdrawal threshold (PWT) and the hind limb weight bearing ability. Joint damage was assessed using histological and microscopic analysis and microcomputerized tomography. Matrix metalloproteinase-13 (MMP13) and nitrotyrosine were detected using immunohistochemistry. Administration of GSPE to the MIA-treated rats significantly increased the PWL and PWT and this resulted in recovery of hind paw weight distribution (P < 0.05). GSPE reduced the loss of chondrocytes and proteoglycan, the production of MMP13, nitrotyrosine and IL-1beta and the formation of osteophytes, and it reduced the number of subchondral bone fractures in the MIA-treated rats. These results indicate that GSPE is antinociceptive and it is protective against joint damage in the MIA-treated rat model of OA. GSPE could open up novel avenues for the treatment of OA.

Grape seed proanthocyanidin extract ameliorates monosodium iodoacetate-induced osteoarthritis

Osteoarthritis (OA) is an age-related joint disease that is characterized by degeneration of articular cartilage and chronic pain. Oxidative stress is considered one of the pathophysiological factors in the progression of OA. We investigated the effects of grape seed proanthocyanidin extract (GSPE), which is an antioxidant, on monosodium iodoacetate (MIA)-induced arthritis of the knee joint of rat, which is an animal model of human OA. GSPE (100 mg/kg or 300 mg/kg) or saline was given orally three times per week for 4 weeks after the MIA injection. Pain was measured using the paw withdrawal latency (PWL), the paw withdrawal threshold (PWT) and the hind limb weight bearing ability. Joint damage was assessed using histological and microscopic analysis and microcomputerized tomography. Matrix metalloproteinase-13 (MMP13) and nitrotyrosine were detected using immunohistochemistry. Administration of GSPE to the MIA-treated rats significantly increased the PWL and PWT and this resulted in recovery of hind paw weight distribution (P < 0.05). GSPE reduced the loss of chondrocytes and proteoglycan, the production of MMP13, nitrotyrosine and IL-1beta and the formation of osteophytes, and it reduced the number of subchondral bone fractures in the MIA-treated rats. These results indicate that GSPE is antinociceptive and it is protective against joint damage in the MIA-treated rat model of OA. GSPE could open up novel avenues for the treatment of OA.

Análise fotocolorimétrica computadorizada dos efeitos da betametasona intra-articular sobre a concentração de proteoglicanos da matriz cartilaginosa de joelhos leporinos: influência do número de injeções intra-articulares / Computerized photocolorimetric analysis of the effects of intraarticular betamethasone on the proteoglycan concentration of leporine knee cartilage matrix: influence of the number of intraarticular injections

OBJETIVO: Analisar os efeitos da injeção repetida de betametasona na concentração de proteoglicanos da cartilagem articular do joelhos normais de coelhos californianos de ambos os sexos. MÉTODOS: Os animais foram randomizados em oito grupos de dez animais cada. Três grupos controle (injeção ou não de solução salina isotônica) e cinco grupos de estudo - doses terapêuticas, repetidas ou não, de betametasona injetadas no joelho direito de cada coelho, com intervalos semanais. Após oito dias da última injeção prevista, cortes histológicos da cartilagem das áreas de apoio dos platôs tibiais foram corados com hematoxilina e eosina para análise por microscopia óptica, e com safranina O para a pesquisa da quantidade de proteoglicanos. A intensidade da coloração da safranina O foi quantificada em aparelho de histomorfometria, composto por microscópio Olympus BX 50 e microcomputador com software Image Pro-plus 4.5Ò. RESULTADOS: Não houve diferenças nos animais que tiveram seus joelhos injetados com betametasona uma, duas e quatro vezes quando comparados com os grupos controle. Nos animais que receberam seis e oito aplicações a intensidade da coloração com safranina O reduziu-se significativamente (p < 0,05) quando comparada tanto com grupos controle quanto com os outros de estudo. CONCLUSÃO: Foi possível demonstrar redução da concentração de proteoglicanos na matriz cartilaginosa articular dependente do efeito deletério cumulativo das repetidas injeções intra-articulares de betametasona.

OBJECTIVE: To study the effects of repeated injections of betamethasone on proteoglycan concentration in the articular cartilage of normal knees of Californian rabbits of both sexes. METHODS: Eighty animals were randomly divided into eight groups of ten animals each. Three control groups (saline solution injected or not) and five study groups - therapeutical doses, repeated or not, of betamethasone injected into the right knee of each animal at weekly intervals. After eight days from the last injection, sections of articular cartilage from tibial plateaus collected from weight-bearing surfaces were stained with hematoxylin and eosin for light microscopy analysis and with safranin O for the proteoglycan content assay. The staining intensity of safranin O was quantified by histomorphometry using an Olympus BX 50 microscope and a microcomputer with the Image Pro-plus 4.5Ò software. RESULTS: Animals receiving one, two and four betamethasone injections showed no differences when compared to normal controls. Animals receiving six and eight injections had a significant decrease in safranin O staining intensity (p < 0.05) as compared to the control groups and the other study groups. CONCLUSION: A decrease in the concentration of articular cartilage proteoglycans dependent on repeated betamethasone injection was effectively demonstrated.

Effect of intraarticular injection of lornoxicam on the articular cartilage & synovium in rat.

BACKGROUND & OBJECTIVE: Intraarticular (i.a) drug application is consider to be a new therapeutic approach for the treatment of postoperative pain after arthroscopic knee surgery without any systemic adverse effects. Lornoxicam, a nonsteroid anti-inflammatory drug is a short acting agent, and its anti-inflammatory and analgesic activity may be effective in the postoperative pain management in minor surgery. In this study, the effects of intraarticular administration of lornoxicam on the synovium and articular cartilage in the rat knee joint were investigated. METHODS: Lornoxicam (0.25 ml) was given as an injection into the right knee joint and 0.25 ml of 0.9 per cent saline solution by injection into the left knee joint as a control in 25 rats. Groups of five rats were sacrificed by a lethal injection of ketamine 1st, 2nd, 7th, 14th and 21st days after lornoxicam administration. Knee joints were detached, fixed in 10 per cent buffered formalin and decalcified. Serial sections of 5 microm were stained with haematoxylin-eosin and evaluated for the presence of inflammation in the articular, periarticular regions and synovium. Inflammatory changes in the joints were graded according to a five-point scale, histologically. RESULTS: There were no significant differences in inflammation and cartilage degeneration, between control and lornoxicam applied knees. Grade 3 inflammatory changes occurred only in one knee in lornoxicam group, at 24 h after injection. No pathological changes were observed in both groups at any time point. INTERPRETATION & CONCLUSION: Lornoxicam did not show significant effect on inflammation on rat synovia in knee joint. Further studies including in human need to be done before any recommendations are made for i.a. administration of lornoxicam.

[ comparison of the efficacy of intra-articular injection of morphine with marcaine in patients to relief the pain associated with knee arthroscopy]

Knee arthroscopy is an approved technique for the diagnosis and treatment of intra-articular lesions. Moderate to severe pain is experienced after surgery; thus, relieving pain post arthroscopy, will help patients in performing their daily activities as soon as possible. Many studies have been performed for reducing pain after arthroscopy. The aim of this study is to compare the efficacy of intra-articular injection of morphine with marcaine in patients for pain relief after arthroscopy. 30 patients were considered for arthroscopic surgery, due to the tearing of the menisci. In this simple non-probability trial, patients were divided in two groups. The first group received 7cc intra-articular marcaine at 0.5% and the second group received 10mg of intra-articular morphine after the arthroscopy. The response was measured by VAS in hours 6, 12, 18, 24 postoperatively and by flexion, extension and walking. The results showed that there was no significant statistical difference between the two groups, except in hour 6 after surgery, indicating marcaine is more effective than morphine. There were no side effects experienced within the two groups. Age, gender, height and weight also had no effect in reducing the pain in patients. Intra-articular Injection of marcaine is more effective than morphine six hours after surgery; however, there are no differences between them after that time frame. More research is needed in order to reduce pain after arthroscopy

Topical analgesics for knee arthrosis: a parallel study of ketoprofen gel and diclofenac emulgel.

The clinical efficacy of the two topical analgesics, ketoprofen hydroalcoholic gel (Fastum gel) and diclofenac emulgel, for osteoarthritis of the knee was studied. There were 85 patients who underwent the trial. They were randomly allocated into 2 groups, the diclofenac group, 42 patients (4 males and 38 females) receiving the diclofenac emulgel at the painfull site four times a day for 4 weeks, and the ketoprofen group, 43 patients (9 males and 34 females) receiving the ketoprofen hydroalcoholic gel four times a day for 4 weeks at the painful knee. Golberg's knee scoring was used to evaluate the patients before the trial, at the end of the first, second and fourth weeks. The ketoprofen group had poorer a score before the trial, however, both groups had improvement in their knee functions, knee score and pain. There was no significant difference between the groups at the end of the study. There was no serious side effect in both groups. Ketoprofen hydroalcoholic gel gave persuasive results in the treatment of knee arthrosis stage I and II.

Effect of sodium hyaluronate on prevention of osteoarthritis

The changes in the surface of articular cartilage of femoral condyle from rabbits were evaluated after degenerative changes were made by the technique advocated by Hulth. The medial collateral and both cruciate ligaments were excised, and a medial menisectomy was done. Then the right knee joint was injected with 1 ml of Na-hyaluronate gel every two weeks. The animals were sacrificed at two, four, six, eight, or sixteen weeks postoperatively. After sacrifice, the medial femoral condyle was excised and prepared for the light microscopic and scanning electron microscopic study. At eight to sixteen weeks, there were chondrocyte clones with clefts to the radial zone and increased loss of the height of articular cartilage on the control side; but, on theexperimental side there was a significant delay and lessening of the arthriticresponse. The biocompatibility and the protective effect of joint degeneration of this device make this material a valuable adjuvant in the treatment ofosteoarthritis and the traumatized joints.

Estudo comparativo com flurbiprofeno versus diclofenaco em osteoartrose / Comparative study with flurbiprofen versus diclofenac in osteoarthrosis

Quarenta pacientes com diagnóstico de osteoartrose de joelhos foram tratados com flurbiprofeno (100 mg duas vezes ao dia) e diclofenaco (50 mg três vezes ao dia), em um estudo comparativo simples-cego, com duraçäo de quatro semanas. O flurbiprofeno demonstrou ser mais eficaz que o diclofenaco, com açäo analgésica evidente. A tolerabilidade das duas drogas foi boa, sem ocorrência de efeitos colaterais importantes