Mast cells and histamine play an important role in edema and leukocyte recruitment induced by Potamotrygon motoro stingray venom in mice.

This work aimed to investigate mechanisms underlying the inflammatory response caused by Potamotrygon motoro stingray venom (PmV) in mouse paws. Pre-treatment of animals with a mast cell degranulation inhibitor (cromolyn) diminished edema (62% of inhibition) and leukocyte influx into the site of PmV injection. Promethazine (histamine type 1 receptor antagonist) or thioperamide (histamine type 3 and 4 receptor antagonist) also decreased edema (up to 30%) and leukocyte numbers, mainly neutrophils (40-50 %). Cimetidine (histamine type 2 receptor antagonist) had no effect on PmV-induced inflammation. In the RBL-2H3 lineage of mast cells, PmV caused proper cell activation, in a dose-dependent manner, with release of PGD2 and PGE2. In addition, the role of COXs products on PmV inflammatory response was evaluated. Indomethacin (COX-1/COX-2 inhibitor) or etoricoxib (COX-2 inhibitor) partially diminished edema (around 20%) in PmV-injected mice. Indomethacin, but not etoricoxib, modulated neutrophil influx into the site of venom injection. In conclusion, mast cell degranulation and histamine, besides COXs products, play an important role in PmV-induced reaction. Since PmV mechanism of action remains unknown, hindering accurate treatment, clinical studies can be performed to validate the prescription of antihistaminic drugs, besides NSAIDs, to patients injured by freshwater stingrays.

Efecto sobre la actividad in vitro de las enzimas cicloxigenasa y 5-lipoxigenasa de los alcoholes octacosanol y el triacontanol / Effects of octacosanol and triacontanol alcohols on ciclooxygenase and 5-lipoxygenase enzyme activities in vitro

Introducción: el policosanol, mezcla de ocho alcoholes purificados de la cera de la caña de azúcar, contiene octacosanol como componente mayoritario. El D-002, mezcla de seis alcoholes alifáticos primarios purificada de la cera de abejas, presenta triacontanol como el componente mayoritario. Aunque ambas sustancias son mezclas de alcoholes de alto peso molecular, exhiben diferente composición y perfil farmacológico como son sus efectos sobre las enzimas del metabolismo del ácido araquidónico: mientras el policosanol inhibe la actividad de ciclooxigenasa (COX)-1, el D-002 inhibe las actividades de la COX y la 5-lipooxigenasa (5-LOX). Objetivo: investigar los efectos del octacosanol y el triacontanol, principales componentes del policosanol y el D-002, respectivamente, sobre las actividades de las enzimas COX y 5-LOX in vitro. Métodos: el policosanol y el triacontanol se suspendieron en vehículo Tween-20/H2O (2 por ciento) (0.6-5000g/mL). Los efectos de la adición de estos alcoholes sobre las actividades de las enzimas COX-1, COX-2 y 5-LOX se evaluaron en microsomas de plaquetas de ratas, microsomas de vesículas seminales de ratas y en preparaciones de polimorfonucleares (PMN) de ratas, respectivamente. Se utilizó indometacina (0.4 µg/mL) como inhibidor de referencia de COX-1 and COX-2 y Lyprinol como inhibidor de 5-LOX. Resultados: la adición de octacosanol inhibió la actividad de COX-1 de modo significativo, marcado (70 por ciento con la concentración mayor) (CI50=143.54 g/mL) y dependiente de la dosis (r=0.991, p <0.001). La adición de triacontanol, sin embargo, no afectó COX-1, pero inhibió de modo significativo y dependiente de la dosis (r=0.985, p <0.001) la actividad de la COX-2 hasta 50 por ciento con 1250 g/mL. En contraste, el octacosanol no modificó la actividad de la COX-2. La indometacina inhibió COX-1...

Introduction: policosanol, a mixture of eight primary aliphatic alcohols purified from sugar cane wax, contains octacosanol as major component. D-002, a mixture of six primary aliphatic alcohols purified from beeswax, presents triacontanol as the main component. Although both substances are high molecular weight alcohol mixtures, they have different compositions and pharmacological effects such as their distinct effects on arachidonic acid metabolism enzymes; whereas policosanol inhibits cyclooxygenase (COX)-1, D-002 inhibits COX and 5-lipoxygenase (5-LOX) activities. Objective: to study the effects of octacosanol and triacontanol, which are main components of policosanol and D-002, respectively on the COX and the 5-LOX enzyme in vitro activities. Methods: triacontanol and octacosanol were suspended in a Tween-20/H2O (2 percent) (0.6-5000 g/mL) vehicle. The effects of adding these alcohols on COX-1, COX-2 and 5-LOX enzymes activities were assessed in rat platelet microsomes, rat seminal vesicle microsomes and rat polymorphonuclear (PMN) preparations, respectively. Indomethacin (0.4µg/mL) was used as reference inhibitor of COX-1 and COX-2, and Lyprinol as 5-LOX inhibitor. Results: octacosanol showed significant, marked (70 percent with highest concentration) (IC50=143.54 g/mL) and dose-dependent (r=0.991, p <0.001) inhibitory action on COX-1 activity. However, Triacontanol did not affect COX-1, but inhibited significantly, depending on dose (r=0.985, p <0.001) the COX-2 activity to 50 percent with 1250 g/mL. In contrast, octacosanol did not change COX-2 activity. Indomethacin inhibited both COX-1...

Effects of octacosanol and triacontanol alcohols on ciclooxygenase and 5-lipoxygenase enzyme activities in vitro / Efecto sobre la actividad in vitro de las enzimas cicloxigenasa y 5-lipoxigenasa de los alcoholes octacosanol y el triacontanol

INTRODUCTION: policosanol, a mixture of eight primary aliphatic alcohols purified from sugar cane wax, contains octacosanol as major component. D-002, a mixture of six primary aliphatic alcohols purified from beeswax, presents triacontanol as the main component. Although both substances are high molecular weight alcohol mixtures, they have different compositions and pharmacological effects such as their distinct effects on arachidonic acid metabolism enzymes; whereas policosanol inhibits cyclooxygenase (COX)-1, D-002 inhibits COX and 5-lipoxygenase (5-LOX) activities. OBJECTIVE: to study the effects of octacosanol and triacontanol, which are main components of policosanol and D-002, respectively on the COX and the 5-LOX enzyme in vitro activities. METHODS: triacontanol and octacosanol were suspended in a Tween-20/H2O (2 %) (0.6-5000 g/mL) vehicle. The effects of adding these alcohols on COX-1, COX-2 and 5-LOX enzymes activities were assessed in rat platelet microsomes, rat seminal vesicle microsomes and rat polymorphonuclear (PMN) preparations, respectively. Indomethacin (0.4µg/mL) was used as reference inhibitor of COX-1 and COX-2, and Lyprinol as 5-LOX inhibitor. RESULTS: octacosanol showed significant, marked (70% with highest concentration) (IC50=143.54 g/mL) and dose-dependent (r=0.991, p <0.001) inhibitory action on COX-1 activity. However, Triacontanol did not affect COX-1, but inhibited significantly, depending on dose (r=0.985, p <0.001) the COX-2 activity to 50 % with 1250 g/mL. In contrast, octacosanol did not change COX-2 activity. Indomethacin inhibited both COX-1 and COX-2 by 83 %. Octacosanol addition was ineffective whereas triacontanol had significant, dose-dependent (r=0.978, p<0.001) and marked effect (79 %) on the 5-LOX activity (IC50=58.74 g/mL). Lyprinol inhibited 5-LOX by 89 %. The inhibitions induced by octacosanol and triacontanol were competitive. CONCLUSIONS: in vitro addition of octacosanol and triacontanol caused differential effects on COX-1, COX-2 and 5-LOX enzyme activities. Whereas octacosanol markedly inhibited COX-1 activity and did not change those of COX-2 and 5-LO, triacontanol markedly inhibited 5-LOX activity, but had moderate effect on COX-2 and did not change COX-1 activity.

INTRODUCCIÓN: el policosanol, mezcla de ocho alcoholes purificados de la cera de la caña de azúcar, contiene octacosanol como componente mayoritario. El D-002, mezcla de seis alcoholes alifáticos primarios purificada de la cera de abejas, presenta triacontanol como el componente mayoritario. Aunque ambas sustancias son mezclas de alcoholes de alto peso molecular, exhiben diferente composición y perfil farmacológico como son sus efectos sobre las enzimas del metabolismo del ácido araquidónico: mientras el policosanol inhibe la actividad de ciclooxigenasa (COX)-1, el D-002 inhibe las actividades de la COX y la 5-lipooxigenasa (5-LOX). OBJETIVO: investigar los efectos del octacosanol y el triacontanol, principales componentes del policosanol y el D-002, respectivamente, sobre las actividades de las enzimas COX y 5-LOX in vitro. MÉTODOS: el policosanol y el triacontanol se suspendieron en vehículo Tween-20/H2O (2 %) (0.6-5000g/mL). Los efectos de la adición de estos alcoholes sobre las actividades de las enzimas COX-1, COX-2 y 5-LOX se evaluaron en microsomas de plaquetas de ratas, microsomas de vesículas seminales de ratas y en preparaciones de polimorfonucleares (PMN) de ratas, respectivamente. Se utilizó indometacina (0.4 µg/mL) como inhibidor de referencia de COX-1 and COX-2 y Lyprinol como inhibidor de 5-LOX. RESULTADOS: la adición de octacosanol inhibió la actividad de COX-1 de modo significativo, marcado (70 % con la concentración mayor) (CI50=143.54 g/mL) y dependiente de la dosis (r=0.991, p <0.001). La adición de triacontanol, sin embargo, no afectó COX-1, pero inhibió de modo significativo y dependiente de la dosis (r=0.985, p <0.001) la actividad de la COX-2 hasta 50 % con 1250 g/mL. En contraste, el octacosanol no modificó la actividad de la COX-2. La indometacina inhibió COX-1 y COX-2 en un 83 %. Mientras la adición del octacosanol no fue efectiva, el triacontanol inhibió de modo significativo, dependiente de la dosis r=0.978, p <0.001) y marcadamente (79 %) la actividad de la 5-LOX (CI50=58.74 g/mL). El Lyprinol inhibió la 5-LOX en un 89 %. Las inhibiciones inducidas por el octacosanol y el triacontanol fueron competitivas. CONCLUSIONES: la adición in vitro de octacosanol y triacontanol produjo efectos diferenciales sobre las actividades enzimáticas de COX-1, COX-2 y 5-LOX. Mientras el octacosanol inhibió marcadamente la actividad de COX-1, sin afectar COX-2 y 5-LOX; el triacontanol inhibió marcadamente 5-LOX, pero moderadamente COX-2, y no cambió la actividad de COX-1.

Estudos dos efeitos de um anti-inflamatório não esteroidal seletivo para COX-2 na osteogênese e na expressão das proteínas COX-2 e RUNX-2 durante o reparo ósseo alveolar em ratos / Effect of a selective anti-infflamatory inhibitor of COX-3 in the osteogenesis and COX-2 and RUNX-2 proteins expression in the alveolar bone healing in rats

Objetivo: No atual trabalho propomo-nos a avaliar morfometricamente possíveis alterações na reparação óssea alveolar pós-exodontia de ratos tratados com Meloxicam, um anti-inflamatório inibidor preferencial da cicloxigenase 2 (COX-2) e correlacionar com a expressão temporal da COX-2 e do fator de transcrição 2 com domínio Runt (Runx-2) associada com a diferenciação de células da linhagem osteoblástica. Material e Métodos: A exodontia do incisivo superior direito foi realizada em 120 ratos Wistar, divididos em grupo controle (n = 60) - animais tratados com injeção intraperitoneal de 0,1 ml de solução salina 0,9% diariamente e grupo tratado (n = 60) animais tratados com injeção de Meloxicam na dose de 3mg/kg de massa corporal, diariamente, ambos durante 7 dias. O volume total do alvéolo (VtA) e do tecido ósseo (VtO), o número de células imunomarcadas/mm² (Nm) para COX-2 e Runx-2 e a expressão protéica por Western blotting (WB) da COX-2 e RUNX-2 foram avaliados nos períodos 3, 7, 10, 14, 21 e 30 dias póscirurgias. Resultados: No grupo tratado o VtA manteve-se constante até os 21 dias, enquanto que no controle foi 0,272 vezes menor em relação aos 3 dias decorrente da maior atividade osteoclástica. Porém, aos 14 dias, no grupo tratado o VtO foi 0,337 vezes menor em relação ao controle decorrente da inibição parcial da transmigração de células inflamatórias responsáveis pela degradação do coágulo e da angiogênese, ocasionando um retardo na formação dos tecidos de granulação/conjuntivo, na diferenciação das células osteoblásticas e na formação/remodelação do tecido ósseo, e consequentemente no reparo ósseo alveolar. A imunomarcação para COX-2 foi observada em diversos tipos celulares, como fibroblastos, células endoteliais, células inflamatórias, osteoblastos e osteócitos. O Nm para COX-2 não apresentou diferenças estatísticas significantes entre os grupos no intervalo de 3 e 21 dias pós-cirurgia, enquanto que, a expressão...

Objective: To evaluate morphometrically possible changes in post-extraction alveolar bone healing in rats treated with Meloxicam, a selective anti-inflammatory inhibitor of cyclooxygenase (COX-2) and to correlate it with the temporal expression of COX-2 and transcription factor 2 with Runt domain (Runx-2) associated with differentiation of osteoblastic lineage cells. Material and Methods: The extraction of the right upper incisor was made in 120 male Wistar rats, divided into control group (n=60) - animals treated with an intraperitoneal injection of 0,1 ml of 0,9% NaCl solution daily for 7 days and the treated group (n=60) - animals treated with injection of 3mg/kg of body weight of Meloxicam 0.9% NaCl solution daily for 7 days. The total alveolar volume (VtA), total bone tissue volume (VtO), number of immunohistochemically positive cells/mm² (Nm) for COX-2 and RUNX-2 and the Western blotting (WB) COX-2 and RUNX-2 protein expressions were evaluated after 3, 7, 10, 14, 21 and 30 days after the surgeries. Results: In the treated group the VtA remained constant until the 21st day, while in the control group at the same day the value was 0,272 times lower compared to the 3 days period, due to the higher osteoclastic activity. However, at 14 days the VtO was 0,337 times lower in the treated group compared to the control due to the partial inhibition of the transmigration of inflammatory cells responsible for the degradation of the clot and angiogenesis, causing a delay in the formation of granulation/connective tissues, differentiation of osteoblastic cells and in bone tissue formation/remodeling, and consequently in the alveolar bone repair. The immunostaining for COX-2 was observed in various cell types, such as fibroblasts, endothelial cells, inflammatory cells, osteoblasts and osteocytes. The Nm for COX-2 showed no statistical differences between groups from the 3rd to the 21st day, while the WB protein expression was on average 0,232 times lower in the...