Evaluation of protein undernourishment on the condylar process of the Wistar rat mandible correlation with insulin receptor expression

The mandible condylar process cartilage (CP) of Wistar rats is a secondary cartilage and acts as a mandibular growth site. This phenomenon depends on adequate proteins intake and hormone actions, including insulin. Objectives The present study evaluated the morphological aspects and the expression of the insulin receptor (IR) in the cartilage of the condylar process (CP) of rats subjected to protein undernourishment. Material and Methods The nourished group received a 20% casein diet, while the undernourished group (U) received a 5% casein diet. The re-nourished groups, R and RR, were used to assess the effects of re-nutrition during puberty and adulthood, respectively. CPs were processed and stained with picro-sirius red, safranin-O and azocarmine. Scanning electron microscopy and immunohistochemistry were also performed. Results The area of the CP cartilage and the number of cells in the chondroblastic layer decreased in the U group, as did the thickness of the CP layer in the joint and hypertrophic layer. Renourishment during the pubertal stage, but not during the adult phase, restored these parameters. The cell number was restored when re-nutrition occurred in the pubertal stage, but not in the adult phase. The extracellular matrix also decreased in the U group, but was restored by re-nutrition during the pubertal stage and further increased in the adult phase. IR expression was observed in all CPs, being higher in the chondroblastic and hypertrophic cartilage layers. The lowest expression was found in the U and RR groups. Conclusions Protein malnutrition altered the cellularity, the area, and the fibrous cartilage complex, as well as the expression of the IRs. .

Possible roles of COX-1 in learning and memory impairment induced by traumatic brain injury in mice

People who suffer from traumatic brain injury (TBI) often experience cognitive deficits in spatial reference and working memory. The possible roles of cyclooxygenase-1 (COX-1) in learning and memory impairment in mice with TBI are far from well known. Adult mice subjected to TBI were treated with the COX-1 selective inhibitor SC560. Performance in the open field and on the beam walk was then used to assess motor and behavioral function 1, 3, 7, 14, and 21 days following injury. Acquisition of spatial learning and memory retention was assessed using the Morris water maze on day 15 post-TBI. The expressions of COX-1, prostaglandin E2 (PGE2), interleukin (IL)-6, brain-derived neurotrophic factor (BDNF), platelet-derived growth factor BB (PDGF-BB), synapsin-I, and synaptophysin were detected in TBI mice. Administration of SC560 improved performance of beam walk tasks as well as spatial learning and memory after TBI. SC560 also reduced expressions of inflammatory markers IL-6 and PGE2, and reversed the expressions of COX-1, BDNF, PDGF-BB, synapsin-I, and synaptophysin in TBI mice. The present findings demonstrated that COX-1 might play an important role in cognitive deficits after TBI and that selective COX-1 inhibition should be further investigated as a potential therapeutic approach for TBI.

Evaluation of the immunoexpression of COX-1, COX-2 and p53 in Crohn's disease / Avaliação da imunoexpressão de COX-1, COX-2 e p53 na doença de Crohn

BACKGROUND: Crohn's disease accompanied by nonspecific or idiopathic ulcerative proctocolitis corresponds to a condition called intestinal inflammatory disease. The immunoexpression of cyclooxygenase 2 (COX-2) in Crohn's disease becomes more marked with progression of the disease and the presence of wild-type p53 suppresses the transcription of COX-2. AIMS: To investigate the immunoexpression of cyclooxygenase 1 (COX-1), COX-2 and p53 in Crohn's ileocolitis and to correlated this expression with clinical and histopathological parameters. METHODS: Forty-five cases of Crohn's disease, 16 cases of actinic colitis (diseased-control group) and 11 cases without a history of intestinal disease (normal control group) were studied. Hematoxylin-eosin-stained sections were submitted to histopathological analysis and the immunohistochemical expression of COX-1, COX-2 and p53 was evaluated by the streptavidin-biotin-peroxidase method. RESULTS: Sixty percent of the Crohn's disease patients were women and 40 percent were men, with 75.5 percent whites and 25.5 percent non-whites. The disease involved the terminal ileum in 44.5 percent of cases, ileum in 33.3 percent, colon in 20 percent and duodenum-ileum in 2.2 percent. A significant association was observed between COX-2 immunoreactivity and age <40 years. Histopathological analysis of Crohn's disease samples showed mild or moderate crypt distortion (57.8 percent and 35.6 percent of cases), atrophy (6.6 percent), mild, moderate and marked chronic inflammation (46.7 percent, 26.7 percent and 20 percent), acute inflammatory activity (93.3 percent), ulceration (24.4 percent), mucin depletion (37.8 percent), Paneth's cells (24.4 percent), intraepithelial lymphocytes (93.3 percent), and subepithelial collagen (6.7 percent). In the CD group, COX-1 immunoreactivity in epithelial and inflammatory cells was observed in 26.7 percent and 22.2 percent of cases, respectively. COX-2 immunoreactivity was detected...

RACIONAL: A doença de Crohn, junto com a colite ulcerativa idiopática ou inespecífica constituem a doença inflamatória intestinal. A imunoexpressão de ciclooxigenase 2 (COX-2) na doença de Crohn acentua-se com a progressão da doença, enquanto que a presença do tipo selvagem de p53 suprime a transcrição de COX-2. OBJETIVOS: Investigar a imunoexpressão de ciclooxigenase 1 (COX-1), COX-2 e p53 na doença de Crohn e correlacionar os achados com parâmetros clínico-histopatológicos. MÉTODOS: Foram estudados 45 casos de doença de Crohn (grupo teste), 16 casos de colite actínica (grupo controle-doente) e 11 casos sem história de doença intestinal (grupo controle normal). A avaliação histopatológica foi feita com lâminas coradas pela hematoxilina-eosina e a imunoexpressão de COX-1, COX-2 e p53 foi avaliada por imunoistoquímica, pelo método da estrepto-avidina-biotina-peroxidase. RESULTADOS: Entre os pacientes com doença de Crohn, 60 por cento eram do sexo feminino e 40 por cento do masculino, 75,5 por cento brancos e 25,5 por cento não-brancos. A doença comprometia o íleo terminal em 44,5 por cento dos casos, íleo em 33,3 por cento, cólon em 20 por cento e duodeno-íleo em 2,2 por cento. Associação significante foi detectada entre a imunoexpressão de COX-2 e pacientes com <40 anos. A histopatologia dos casos de doença de Crohn mostrou distorção críptica em grau leve ou moderado (57,8 por cento e 35,6 por cento dos casos), atrofia (6,6 por cento), inflamação focal, difusa superficial e difusa transmural (46,7 por cento, 26,7 por cento e 20 por cento), inflamação aguda neutrofílica (93,3 por cento), alterações epiteliais: ulceração (24,4 por cento), depleção de mucina (37,8 por cento), células de Paneth (24,4 por cento); alterações epiteliais associadas: linfócitos intra-epiteliais (93,3 por cento) e colágeno subepitelial (6,7 por cento). No grupo doença de Crohn, imunoexpressão de COX-1, em células epiteliais e inflamatórias foi observada em 26,7...

Immunoexpression of cyclooxygenase-1 and -2 in ulcerative colitis

Ulcerative colitis (UC) is a disease of the colon and rectum characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events. Prostaglandins are synthesized by cyclooxygenase (COX)-1 and -2 and exhibit both pro- and anti-inflammatory activity. To evaluate COX-1 and COX-2 immunoexpression in 42 cases of UC and to correlate it with clinicopathological parameters, COX-1 and COX-2 expression was investigated by the immunohistochemistry method. Only patients with all pertinent clinical and evolutive data as well as with adequate biopsy material were included in the study. Fifteen samples of colorectal adenocarcinoma and 14 of large bowel with no histological changes were used for positive and negative controls, respectively. UC patients showed COX-1 immunoreactivity in epithelial cells in 29 percent of the cases and in inflammatory cells in 43 percent. COX-2 positivity in epithelial and inflammatory cells was found in 69 percent of the samples. The comparison between UC and the control groups revealed that the UC group had significantly more positive cases for COX-1 and COX-2 in inflammatory cells. Immunohistochemistry allowed the identification of COX-1 and COX-2 expression in epithelial and inflammatory cells in UC biopsies. No significant difference between COX-1 and COX-2 immunoreactivity in epithelial and inflammatory cells was observed regarding the clinicopathological parameters. COX-2 presented low expression in normal colon and high expression in colorectal adenocarcinoma. COX-2 might play a role in the pathophysiologic processes of inflammatory bowel disease and the development of neoplasia. Treatment with selective COX-2 inhibitors might be an additional option for therapy.

COX-2 Inhibitors in Inflammatory Bowel Disease: Friends or Foes? / 대한소화기학회지

The cyclooxygenase (COX) is a key enzyme in the coversion of arachidonic acid to prostaglandins. COX-1 is constitutively expressed and is a critical housekeeping gene, whereas COX-2 is rapidly upregulated by growth factors and cytokines and thus responsible for inflammation. COX-2 is frequently overexpressed in colonic adenoma and carcinoma. Specific inhibitors of COX-2 have been shown to induce apoptosis in tumor cells and to inhibit tumor growth in animal models and in humans. Long-standing IBD patients have increased risk of developing colorectal cancer compared to general population. IBD-associated colorectal carcinogenesis is probably promoted by chronic inflammation and closely related to COX-2. In a recent study, powerful chemopreventive ability of selective COX-2 inhibitor was observed in colitis-related colon carcinogenesis in mouse model. But it was reported that even selective COX inhibitors aggravated the DSS-induced colonic inflammation. It is assumed that endogenous PGs are involved in the mucosal defense against DSS-induced colonic ulcerations which are produced by COX-1 at early phase and by COX-2 at late phase. Long-term use of COX-2 inhibitors for the chemoprevention of colitic cancer is needed to define their mechanism of action, that reduce side effects and have specific tumor target.

The expression of COX-1 and COX-2 following brain injuries / 法医学杂志

Cyclooxygenase (COX) is the obligate, rate-limiting enzyme for the conversion of arachidonic acid into prostaglandins, which mediate mitogenesis, apoptosis, angiogenesis, blood flow, secondary injury, and inflammation. COX is consist of 2 subtypes: COX-1 and COX-2. In recent years, there are a number of lines of evidence that COX-1 and COX-2 play a important in role brain injuries.