RESUMO
INTRODUCTION: All-inside posteromedial suture for lesions of the posterior horn of the medial meniscus in anterior cruciate ligament (ACL) repair provides effective freshening and good healing. HYPOTHESIS: The posteromedial portal provides satisfactory healing rates without increasing morbidity or complications rates. MATERIAL AND METHODS: Intra- and postoperative complications were collected for a consecutive single-center series of 132 patients undergoing posteromedial hook suture of the medial meniscus in ACL repair. Meniscal healing was assessed as the rate of recurrence of symptomatic medial meniscus lesions (Barret criteria) and on revision surgery, if any, in terms of the aspect and extent of the iterative lesion. The severity of any sensory disorder was assessed by questionnaire. RESULTS: The intraoperative complications rate was 1.5% (2 saphenous vein punctures). At a mean 31months (range, 28-35months), there was no loss to follow-up. Twelve patients (9%) showed symptomatic recurrence of the medial meniscus lesion, requiring 10 repeat surgeries. In 6 cases (4.5%), the iterative lesion involved a smaller, more central part of the meniscus anterior to the sutures, of "postage-stamp" effect, possibly implicating the suture hook and/or non-absorbable sutures. There were no cases of infection or fistula. Postoperative hematoma occurred in 7% of patients. In total, 1.8% reported dysesthesia areas equal to or greater than the size of a credit card (45cm2). DISCUSSION: Some retears, or "partial failures", may implicate a new lesion caused by the suture hook and possibly prolonged by non-resorbable sutures. Hematoma and sensory disorder rates were comparable to those reported in isolated ACL repair without posteromedial portal. CONCLUSION: The present results show that posteromedial arthroscopic hook suture in posterior medial meniscus tear provides good healing rates without increased morbidity due to the supplementary portal. LEVEL OF EVIDENCE: IV.
Assuntos
Artroscopia , Complicações Intraoperatórias , Complicações Pós-Operatórias , Técnicas de Sutura/instrumentação , Lesões do Menisco Tibial/cirurgia , Adolescente , Adulto , Reconstrução do Ligamento Cruzado Anterior , Criança , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Reoperação/estatística & dados numéricos , Tendões/transplante , Adulto JovemRESUMO
BACKGROUND: Tibial spine avulsion fractures (TSAFs) occur chiefly in adolescents. Few published data are available on outcomes after arthroscopic surgical treatment of TSAFs in adults. OBJECTIVES: To evaluate outcomes of consecutive patients with TSAFs managed by arthroscopic bone suture followed by a standardised non-aggressive rehabilitation programme. HYPOTHESIS: Arthroscopic bone suture followed by non-aggressive rehabilitation therapy reliably produces satisfactory outcomes in adults with TSAF. METHODS: Thirteen adults were included. Outcomes were evaluated based on the Tegner score, International Knee Documentation Committee (IKDC) score, anterior-posterior knee laxity, passive and active motion ranges, and radiological appearance. RESULTS: After a mean follow-up of 41±27months (12-94months), all 13 patients had healed fractures without secondary displacement. No patient had knee instability. Post-operative stiffness was noted in 5 patients (2 with complex regional pain syndrome and 3 with extension lag), 1 of whom required surgical release. The mean IKDC score was 91.3±11.7. The mean Tegner score was 5.46±1.37 compared to 6.38±0.70 before surgery. Mean tibial translation (measured using the Rolimeter) was 1.09±1.22mm, compared to 5.9±1.85mm before surgery. CONCLUSION: The outcomes reported here support the reliability of arthroscopic bone suture for TSAF fixation. Nevertheless, a substantial proportion of patients experienced post-operative stiffness, whose contributory factors may include stunning of the quadriceps due to the short time from injury to surgery and the use of a gentle rehabilitation programme. LEVEL OF EVIDENCE: IV, retrospective study of treatment outcomes.
Assuntos
Artroscopia , Fratura Avulsão/cirurgia , Articulação do Joelho/fisiopatologia , Complicações Pós-Operatórias/reabilitação , Amplitude de Movimento Articular/fisiologia , Suturas , Fraturas da Tíbia/cirurgia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Complicações Pós-Operatórias/fisiopatologia , Prevalência , Estudos Retrospectivos , Adulto JovemRESUMO
INTRODUCTION: Trochlear dysplasia is one of the main elements of patellofemoral instability. Although correction by trochleoplasty seems logical, the long-term outcome of this procedure is unknown and the progression to osteoarthritis has not been clarified. Thus, we performed a retrospective study of a series of sulcus deepening trochleoplasties with a 15-year follow-up whose goal was to (1) evaluate the long-term clinical outcome and radiological rate of osteoarthritis, and (2) define the results in relation to the type of instability and the grade of dysplasia. HYPOTHESIS: Sulcus deepening trochleoplasty is an effective procedure to stabilize the patellofemoral joint that does not increase the risk of osteoarthritis. PATIENTS AND METHODS: This retrospective study analyzed 34 sulcus deepening trochleoplasties based on clinical scores (IKS, Lille, Kujala and Oxford scores) and radiological results (stage of osteoarthritis according to the Iwano score) after a mean follow-up of 15 years (12-19 years). An Insall procedure was systematically associated with an anterior tibial tubercle transfer in 17 cases (7 prior tibial transfers). RESULTS: No recurrent objective instability was observed. Seven knees had additional surgery after a mean follow-up of 7 years (2-16): 7 underwent conversion to total knee arthroplasty because of progression of osteoarthritis and one knee had tibial tubercle transfer for pain and episodes of the knee giving way. The mean Lille, Kujala and IKS scores increased from 53.3 (30-92), 55 (13-75) and 127 (54-184) to 61.5 (25-93), 76 (51-94) and 152.4 (66-200) respectively between preoperative and follow-up assessment (P<0.05) (revisions included). Functional outcome was significantly better for dysplasia with supratrochlear spurs (IKS score 168 [127-200] versus 153 [98-198] and Kujula score 81.5 [51-98] versus 76 [51-94] [P<0.05]). Patients were satisfied in 65% of the cases and the total mean Oxford score was 24.1/60 (12-45 points). Occasional pain was present in 53% of the cases. The trochlear prominence decreased from 4.9 mm (3-9 mm) to -1.2mm (-7-4mm). Ten cases of preoperative patellofemoral osteoarthritis were identified, but none with>Iwano 2, while osteoarthritis was present in 33/34 cases at the final follow-up with 20 cases>Iwano 2 (65%). DISCUSSION: Sulcus deepening trochleoplasty corrects patellofemoral stability even in patients with severe dysplasia and the long-term functional outcome is better in this group. It does not prevent patellofemoral osteoarthritis. It should be limited to severe dysplasia with supratrochlear spurs and associated with procedures to realign the extensor apparatus.
Assuntos
Artroplastia do Joelho/métodos , Previsões , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Luxação Patelar/cirurgia , Articulação Patelofemoral/cirurgia , Adolescente , Adulto , Progressão da Doença , Feminino , Fêmur/cirurgia , Seguimentos , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/fisiopatologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Luxação Patelar/diagnóstico por imagem , Luxação Patelar/fisiopatologia , Articulação Patelofemoral/diagnóstico por imagem , Articulação Patelofemoral/fisiopatologia , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Adulto JovemRESUMO
INTRODUCTION: Anterior knee pain (AKP) is a rare and difficult complication following anterior cruciate ligament (ACL) reconstruction. This disabling pain is persistent with conventional rehabilitation protocols. The aim of this work is to validate a new rehabilitation protocol that may improve the patients and allow return to daily activities including sports. MATERIALS AND METHODS: Forty-three patients identified with functional AKP after ACL reconstruction was enrolled in the rehabilitation protocol between 2009 and 2011. The series included twenty-six patients with hamstring grafting and seventeen patients with patellar tendon transplant. This study compares the functional outcomes and pain scores before and after the isokinetic protocol until the last follow-up at an average of 25.7 months after surgery. The evaluation was performed according to the International Knee Documentation Committee (IKDC) and included a pain assessment using the visual analog scale. Statistical analysis used Student's t-test for unpaired data and the Pearson correlation test for the variables. The IKDC scores were compared by the Wilcoxon test. RESULTS: Functional outcomes and pain are significantly improved (p<0.0001). The average IKDC score improved with 28 points and the pain improved with 3.2 points on the visual analog scale (VAS). The results are correlated with the follow-up time (p=0.008) but not correlated with the delay between the surgery and the beginning of the isokinetic protocol. DISCUSSION: Isokinetic rehabilitation provides a significant improvement in the knee function as measured by the IKDC score and by the VAS, regardless of the painful period preceding the program. The function improvement continues after the end of the protocol, but the pain may not completely disappear. The isokinetic rehabilitation program may resume functional AKP related to muscular deficit and may be used as the starter of other physical therapy protocols. LEVEL OF EVIDENCE: IV.
Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Artralgia/reabilitação , Terapia por Exercício/métodos , Articulação do Joelho , Adulto , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Artralgia/etiologia , Humanos , Masculino , Força Muscular/fisiologia , Dinamômetro de Força Muscular , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/reabilitação , Músculo Quadríceps/fisiologia , Estudos RetrospectivosRESUMO
Acute hamstring strains are a common athletic injury, which may be treated non-operatively with a satisfactory outcome. A complete proximal hamstring avulsion is a rare and potentially career ending injury to an elite athlete. For these high demand patients, surgical reattachment should be immediately undertaken to shorten return to sport and to improve functional outcome. This report describes the occurrence of a complete avulsion of the proximal hamstrings in a professional footballer during an international match. We highlight the clinical presentation, the appropriate diagnostic investigations, the surgical technique and the rehabilitation protocol for this injury. The successful surgical reattachment of the common hamstring tendon was confirmed by magnetic resonance imaging done 5 months after repair and allowed the player a full return to competition at 6 months after surgery. Hamstrings isokinetic peak torque was 80% at 6 months and 106% at 11 months after repair comparing with the uninjured side.
Assuntos
Futebol/lesões , Traumatismos dos Tendões/cirurgia , Humanos , Perna (Membro) , Masculino , Procedimentos Ortopédicos/métodos , Adulto JovemRESUMO
During arthroscopic ACL reconstruction, intra-articular visualization can be compromised by the interposition of the infrapatellar fat pad (IPFP) between the scope and the notch. In this technical note, we describe our technique of using lateral higher arthroscopic portal, starting arthroscopy with the resection of the ligamentum mucosum and performing the tibial tunnel in 40° of knee flexion to optimise the intra-articular view without IPFP debridement. This technique was performed in 112 consecutive arthroscopic ACL reconstructions and compared to that in the previous 112 cases in which a conventional method was used. The use of this technique was associated with a shorter operative time and no increase in the difficulty in performing associated meniscal procedures.
Assuntos
Tecido Adiposo/transplante , Ligamento Cruzado Anterior/cirurgia , Artroscópios , Artroscopia/métodos , Traumatismos do Joelho/cirurgia , Patela/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Lesões do Ligamento Cruzado Anterior , Desenho de Equipamento , HumanosRESUMO
It has been suggested that an increased posterior tibial slope (PTS) and a narrow notch width index (NWI) increase the risk of anterior cruciate ligament (ACL) injury. The aim of this study was to establish why there are conflicting reports on their significance. A total of fifty patients with a ruptured ACL and 50 patients with an intact ACL were included in the study. The group with ACL rupture had a statistically significantly increased PTS (p < 0.001) and a smaller NWI (p < 0.001) than the control group. When a high PTS and/or a narrow NWI were defined as risk factors for an ACL rupture, 80% of patients had at least one risk factor present; only 24% had both factors present. In both groups the PTS was negatively correlated to the NWI (correlation coefficient = -0.28, p = 0.0052). Using a univariate model, PTS and NWI appear to be correlated to rupture of the ACL. Using a logistic regression model, the PTS (p = 0.006) and the NWI (p < 0.0001) remain significant risk factors. From these results, either a steep PTS or a narrow NWI predisposes an individual to ACL injury. Future studies should consider these factors in combination rather than in isolation.
Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos do Joelho/patologia , Articulação do Joelho/patologia , Tíbia/patologia , Adolescente , Adulto , Ligamento Cruzado Anterior/patologia , Métodos Epidemiológicos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Ruptura/etiologia , Ruptura/patologia , Adulto JovemRESUMO
Pancreatic phospholipase A2 (PLA(2)-I) stimulates U(III) cells proliferation, a rat uterine cell line, after binding to membrane receptors, internalization and translocation. Here, we demonstrate that during these steps of internalization, PLA(2)-I retains its hydrolytic activity and thus could exert its proliferative effect via nuclear phospholipids hydrolysis. Since fatty acids and eicosanoids released by such activity are known to be ligands of PPAR, we study the expression of these nuclear receptors and demonstrate that, in the experimental conditions where PLA(2)-I stimulates U(III) cells proliferation, PLA(2)-I also regulates PPAR expression indicating a possible mechanism of its proliferative effect.
Assuntos
Núcleo Celular/metabolismo , Fosfolipases A/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Divisão Celular , Linhagem Celular , Eicosanoides/metabolismo , Ativação Enzimática , Feminino , Fosfolipases A2 do Grupo II , Hidrólise , Microscopia de Fluorescência , Fosfolipases A2 , Fosfolipídeos/metabolismo , Ratos , Fatores de Tempo , Transdução Genética , Útero/metabolismoRESUMO
The mechanisms underlying arachidonic acid (AA) release by uterine stromal (U(III)) cells were studied. Stimulation of AA release by calcium ionophore and PMA are inhibited by various PKC inhibitors and by calcium deprivation. These results suggest the involvement of an AA-specific cPLA2 as the release of docosahexaenoic acid (DHA) from prelabelled cells is much lower than the release of AA. The results also show a more original stimulation of AA and DHA release induced by PKC inhibitors, which is insensitive to calcium deprivation. This stimulation is not due to acyltransferase inhibition, suggesting the participation of a Ca2+-independent PLA2 (iPLA2). However, iPLA2 activity measured in U(III) cells is inhibited by the specific iPLA2 inhibitor, BEL, and is not stimulated by PKC inhibitors, in contrast with the AA and DHA release. It seems therefore that this iPLA2 cannot be involved in this mechanism. The participation of another iPLA2, BEL-insensitive, is discussed.
Assuntos
Ácido Araquidônico/metabolismo , Cálcio/fisiologia , Ácidos Docosa-Hexaenoicos/metabolismo , Inibidores Enzimáticos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Útero/citologia , Aciltransferases/fisiologia , Animais , Calcimicina/farmacologia , Feminino , Fosfolipases A/efeitos dos fármacos , Fosfolipases A/metabolismo , Fosfolipases A2 , Fosfolipídeos/metabolismo , Ratos , Transdução de Sinais/fisiologia , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , TrítioRESUMO
We have previously demonstrated that pancreatic PLA2 (PLA2-I) stimulates the proliferation of UIII cells, a stromal cell line derived from normal rat uterus. In order to gain further insight into the mechanism of action of PLA2-I, we have investigated the intracellular processing of PLA2-I. Either highly proliferative or growth arrested UIII cells were analyzed. Growth arrested cells were obtained from a contact inhibited monolayer or from aristolochic acid-treated cultures. Using cellular fractionation, western blotting, immunocytochemistry and confocal microscopy, we demonstrate that endogenous PLA2-I was mainly located in the nucleus in highly proliferative cells whereas its location was cytoplasmic in non proliferative cells. When non confluent UIII cells were incubated with nanomolar amounts of exogenous PLA2-I, the enzyme was internalized and, in the majority of cells, appeared within the nucleus. Both internalization and nuclear location of exogenous PLA2-I were suppressed by the addition of aristolochic acid to the culture medium. Binding experiments performed on purified nuclear preparations showed the presence of specific cooperative binding sites for PLA2-I. Collectively our data suggest that the proliferative effect exerted by pancreatic PLA2 in UIII cells is mediated by a direct interaction of the enzyme at the nuclear level. Putative mechanisms and targets are discussed.
Assuntos
Núcleo Celular/enzimologia , Fosfolipases A/metabolismo , Animais , Sítios de Ligação , Divisão Celular , Linhagem Celular , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Ativação Enzimática , Feminino , Isoenzimas/metabolismo , Fosfolipases A2 , Ligação Proteica , Ratos , Células Estromais , Frações Subcelulares/enzimologia , Frações Subcelulares/metabolismo , Frações Subcelulares/ultraestrutura , ÚteroRESUMO
It is well known that arachidonic acid, as a substrate of prostaglandin G/H synthase (PGHS), is converted into prostaglandins of the two-series. In this work, we attempted to determine whether arachidonic acid and prostaglandin E2 might regulate the expression of PGHS and the pancreatic-type phospholipase A2 (PLA2I), which may be involved in the liberation of arachidonic acid from membrane phospholipids. For this purpose, we used the uterine stromal cell line UIII, which produces prostaglandin E2 and expresses both the constitutive and inducible PGHS enzymes (PGHS1 and PGHS2) and PLA2 I. The results show that PGHS1, which is expressed at a high level in UIII cells, was not modified by arachidonic acid. The expression of PGHS2 and PLA2 I was up-regulated by increasing arachidonate concentrations (1-10 microM). The maximal response was obtained at 24 h, reaching a 2.3-fold and 2.6-fold increase for PGHS2 and PLA2 I expression, respectively, compared to the control level. To discriminate between the effect of arachidonic acid and that of prostaglandins, which are highly increased in the presence of exogenous arachidonic acid, we treated the cells with two inhibitors of PGHS activity, aspirin and meclofenamic acid. Both inhibitors failed to suppress the arachidonate-induced increase of PLA2 I and PGHS2 expression and even enhanced it either in the presence or absence of arachidonic acid. In contrast, the addition of prostaglandin E2 to the culture medium decreased the expression of both enzymes in a dose-dependent manner, the maximal response being reached at 1 microM. We conclude that arachidonic acid up-regulates the expression of PLA2 I and PGHS2 in the uterine stromal cells, independently of prostanoids, and that prostaglandin E2 is capable of down-regulating enzyme expression.
Assuntos
Ácido Araquidônico/farmacologia , Inibidores de Ciclo-Oxigenase/metabolismo , Dinoprostona/farmacologia , Ocitócicos/farmacologia , Fosfolipases A/metabolismo , Regulação para Cima , Útero/metabolismo , Animais , Aspirina/farmacologia , Células Cultivadas , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Feminino , Regulação Enzimológica da Expressão Gênica , Ácido Meclofenâmico/farmacologia , Fosfolipases A2 , Ratos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/enzimologia , Células Estromais/metabolismo , Útero/citologia , Útero/efeitos dos fármacos , Útero/enzimologiaRESUMO
Uterine stromal cells produce and release PGE2, both processes being regulated by hormonal factors. In this study, we examined the effect of PRL on the PGE2 production and release measured by radioimmunoassay. For this purpose, we used a rat uterine stromal cell line, UIII cells, which produce PGE2 and contain PRL receptors. The expression of sPLA2I and PGHS (PGHS1 and PGHS2), enzymes required for PGE2 production, was also estimated by immunocytochemistry and 'Western blotting' in response to PRL. PRL (10 to 60 ng/ml) significantly increased the PGE2 release (up to 6-fold) and production, in a dose-dependent manner. Results show that PGHS1 and PGHS2 are both expressed constitutively in the uterine UIII cells, although PGHS2 is expressed at a low level. PRL did not increase PGHS1 expression, but stimulated the expression of sPLA2I and PGHS2 by 3.5- and 2.5-fold, respectively. These data show for the first time a regulation of sPLA2I and PGHS2 expression by PRL and may indicate that, in uterine cells, PRL enhances the PGE2 release and production by increasing the expression of both sPLA2I and PGHS2.
Assuntos
Dinoprostona/biossíntese , Isoenzimas/biossíntese , Fosfolipases A/biossíntese , Prolactina/farmacologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Transdução de Sinais/efeitos dos fármacos , Células Estromais/metabolismo , Útero/metabolismo , Animais , Células Cultivadas , Ciclo-Oxigenase 2 , Feminino , Fosfolipases A2 , Ratos , Regulação para CimaRESUMO
Rat uterine stromal cells (U(III)) express pancreatic type PLA2 (PLA2-I) receptor and internalize the enzyme bound to receptors. Here, we investigate the proliferating effect and alterations in binding of PLA2-I. There is a dramatic decline in PLA2-I binding in U(III) cells as they progress from a non-confluent proliferating state (40,000 sites/cell) to a confluent state (1300 sites/cell). Intracellular concentration of PLA2-I changed with the alteration in binding, suggesting that regulation in the PLA2 binding capacity may have important implications in growth control mechanisms.
Assuntos
Ácidos Aristolóquicos , Divisão Celular , Fosfolipases A/metabolismo , Receptores de Superfície Celular/metabolismo , Útero/citologia , Útero/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Feminino , Pâncreas/metabolismo , Fenantrenos/farmacologia , Fosfolipases A/antagonistas & inibidores , Fosfolipases A/farmacologia , Fosfolipases A2 , Ligação Proteica , Ratos , Receptores da Fosfolipase A2 , Células Estromais/citologia , Células Estromais/metabolismo , SuínosRESUMO
The cellular uptake of extracellular type-I phospholipase A2 (PLA2) was investigated in rat uterine stromal cells (UIII) in culture, which were found to express the high-affinity binding site for mammalian type-I PLA2, with a measured KD of 6.4 nM, a Bmax of 0.1-1 pmol/mg of DNA at 4 degrees C, and a molecular mass of about 200 kDa. When UIII cells were treated with type-I PLA2 at 37 degrees C, the ligand specifically associated with the cells increased, reaching a plateau after 90 min of incubation, whose level was about 5-fold higher than that measured if cells were maintained at 4 degrees C. We could determine that the PLA2 was bound to plasma membrane receptors which were responsible for internalization of the ligand, and that the binding sites were still suitable for binding at the level of plasma membrane during UIII cell incubation at 37 degrees C. Proteolysis of internalized PLA2 could be clearly detected only after 90 min of UIII cell incubation with the ligand at 37 degrees C, and most of the intracellular PLA2 consisted of the apparently intact 14 kDa enzyme. By cross-linking studies, we found that most of the internalized PLA2 was not associated with the receptor, supporting the conclusion that in our experimental system a single pool of membrane receptors for mammalian type-I PLA2 undergoes cycles of ligand binding, intracellular transfer and release of PLA2, followed by restoration of binding sites on the plasma membrane. We calculated that the rate of internalization of the ligand by one receptor molecule in UIII cells at 37 degrees C is about three molecules of type-I PLA2 per h.
Assuntos
Fosfolipases A/metabolismo , Útero/enzimologia , Animais , Sítios de Ligação , Transporte Biológico Ativo , Células Cultivadas , Reagentes de Ligações Cruzadas , Espaço Extracelular/enzimologia , Feminino , Cinética , Ligantes , Fosfolipases A2 , Ratos , Receptores de Superfície Celular/metabolismo , Suínos , Útero/citologia , Útero/metabolismo , ViperidaeRESUMO
To gain some insight into the mechanisms involved in the opposing effects of arachidonic acid and docosahexaenoic acid on the growth of rat uterine stromal cells (UIII cells), the dynamics of the uptake, conversion, and incorporation of labeled 18:2(n-6), 18:3(n-3), 20:4(n-6), 20:5(n-3), and 22:6(n-3) into lipid pools and phospholipid subclasses were examined. A very active and time-dependent conversion of [14C]18:3(n-3) to higher homologs was observed; 64.7 +/- 0.7 and 11.5 +/- 0.4% of the [14C] radioactivity incorporated in cellular lipids was recovered as 22:5(n-3) and 22:6(n-3) after 72 h incubation, respectively. The distribution of labeled fatty acids obtained after 72 h incubation with [3H]20:5(n-3) was not significantly different from that observed with 18:3(n-3). Arachidonic acid was the major fatty acid formed from [14C]18:2(n-6) and only trace amounts of 22:5(n-6) were detected. When cells were incubated for 72 h with 20:4(n-6), more than 75% of the radioactivity was recovered as arachidonate and slightly higher amounts of 22:4(n-6) and 22:5(n-6) were formed compared to those obtained after incubation with 18:2(n-6). Using both [14C]- and [3H]22:6(n-3), no significant retroconversion of labeled 22:6(n-3) occurred in the cells. More than 90% of labeled 20:4(n-6) and 22:6(n-3) taken up by the cells were esterified into phospholipids, but significant differences in their distribution among phospholipid classes and subclasses were observed. Docosahexaenoic acid was more rapidly and efficiently incorporated into phosphatidylethanolamine than 20:4(n-6) and was principally recovered in plasmalogens. Arachidonic acid was mainly incorporated in the diacyl subclasses of phosphatidylcholine and phosphatidylethanolamine and in phosphatidylinositol. The divergent profiles of these two fatty acids within the phospholipid compartments provide some information for the mechanisms of their opposite effects on UIII cell growth.
Assuntos
Ácidos Araquidônicos/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Útero/metabolismo , Animais , Ácidos Araquidônicos/isolamento & purificação , Ácidos Araquidônicos/farmacologia , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Ácidos Docosa-Hexaenoicos/isolamento & purificação , Ácidos Docosa-Hexaenoicos/farmacologia , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Graxos Insaturados/metabolismo , Feminino , Cinética , Fosfolipídeos/isolamento & purificação , Fosfolipídeos/metabolismo , Técnica de Diluição de Radioisótopos , Ratos , Fatores de Tempo , Trítio , Útero/citologia , Útero/efeitos dos fármacosRESUMO
The effect of different families of fatty acids on the proliferation of rat uterine stromal cells (UIII) was studied. Docosahexaenoic acid (DHA) exerted a strong and dose-dependent inhibitory effect (IC50 approximately 2 microM), whereas arachidonic acid (AA) stimulated UIII cell proliferation at the optimal concentration of 10 microM. Oleic, linoleic and linolenic acids were ineffective from 0.1 to 10 microM. The inhibitory effect of DHA was independent of the eicosanoid biosynthesis and lipid peroxidation, since it was not reversed by the addition of the antioxidant BHT and no significant production of oxidized species from DHA occurred in our culture conditions.
Assuntos
Divisão Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Células Estromais/citologia , Útero/citologia , Animais , Ácido Araquidônico/farmacologia , Hidroxitolueno Butilado/farmacologia , Células Cultivadas , DNA/biossíntese , Ácidos Docosa-Hexaenoicos/administração & dosagem , Relação Dose-Resposta a Droga , Ácidos Graxos/farmacologia , Feminino , Peroxidação de Lipídeos/efeitos dos fármacos , RatosRESUMO
The phospholipase A2 (PLA2) activity was measured in the oviduct of immature and estradiol benzoate (EB)-treated quails. The pH profiles demonstrate the presence of two PLA2 isoforms in the avian oviduct: a neutral isoform, optimally active at pH 7-7.5 and calcium independent, responsible for most of the hydrolytic activity in the immature oviduct and poorly stimulated by estradiol; and an alkaline isoform, optimally active at pH 8-9.5 and calcium dependent, with little activity in the immature tissue but markedly stimulated by EB. After EB injection, PLA2 activation occurs at first during the prereplicative period of oviduct cells (+172% at 6 h), it is dose dependent from 0.01 to 1 mg/kg EB and can be prevented by cycloheximide together with ornithine decarboxylase activation. Moreover, estradiol was inactive on cell-free extracts of immature oviducts. These results suggest that EB increases PLA2 activity through gene activation and de novo protein synthesis. The correlation between the early stimulation of PLA2 activity and the proliferation of oviduct cells is discussed.
Assuntos
Estradiol/farmacologia , Tubas Uterinas/efeitos dos fármacos , Tubas Uterinas/enzimologia , Fosfolipases A/metabolismo , Animais , Divisão Celular , Coturnix , Ativação Enzimática , Feminino , Humanos , Cinética , Fosfolipases A2RESUMO
The phospholipid composition and the molecular species of the major subclasses of ethanolamine and choline glycerophospholipids were determined during the natural or oestradiol-induced development of the quail oviduct. The phospholipid concentration increased significantly during oviduct development, and the proportion of ethanolamine glycerophospholipids (EPL) remained constant while that of choline glycerophospholipids increased. The immature oviduct contained the majority of its endogenous arachidonic acid mass (71%) in EPL, mainly in alkenylacyl-glycerophosphoethanolamine (alkenylacyl-GPE) (49% of the total). Oestrogen treatment induced the depletion of 20:4,n-6 specifically from this pool, which indicates the biological importance of 20:4,n-6 molecular species in alkenylacyl-GPE as substrates for the oviduct phospholipases activated by oestradiol, and suggests that this EPL subclass is involved in the oestrogen-induced cell proliferation. Another striking result was the marked increase in 22:6,n-3 EPL molecular species following the oestradiol treatment and more particularly the strict substitution of 20:4,n-6 by 22:6,n-3 in alkenylacyl-GPE. We speculate that alkenylacyl-GPE molecular species containing 22:6,n-3 may participate in the arrest of oestrogen-induced proliferation.
Assuntos
Ácido Araquidônico/metabolismo , Coturnix/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Estradiol/farmacologia , Oviductos/metabolismo , Fosfatidiletanolaminas/metabolismo , Fosfolipídeos/metabolismo , Animais , Feminino , Oviductos/efeitos dos fármacos , Oviductos/crescimento & desenvolvimento , Fosfatidilcolinas/metabolismo , Maturidade SexualRESUMO
We have recently established a uterine stromal cell line (UIII). The purpose of the present study was to determine whether these cells have retained the ability to produce and release prostaglandins after several passages and whether this production was regulated. UIII cells, grown in basal conditions, released a very low amount (40.6 +/- 2.9 pg/24h/10(6) cells) of prostaglandin E2 (PGE2) though cellular content was more elevated (192 +/- 23 pg/10(6) cells). Ethanol increased the cellular content but decreased the release of PGE2, whereas estradiol 17 beta (E2) increased it in a dose-dependent manner, but had no effect on the cellular content. The PGE2 release by cells grown in medium containing 10 microM arachidonate (AA) reached 1.39 +/- 0.05 ng/24h/10(6) cells, and was further increased to 2.1 +/- 0.1 ng/24 h/10(6) cells by the addition of ethanol. Under the latter condition, E2 was ineffective. This study also showed that UIII cells expressed an immunoreactive pancreatic type 14 kD PLA2. A substantial increased 14 kD PLA2 expression was observed in ethanol-treated cells, suggesting that ethanol-effect on prostaglandin production might be partly mediated by PLA2 increase. Medium supplementation with arachidonate also resulted in a significant increase of intracellular 14 kD PLA2 expression. The present results showed that uterine stromal UIII cells have retained the enzymatic machinery to produce PGE2. Moreover these data demonstrate that ethanol and E2 affect differently uterine PGE2 production.