A Medicinal Extract ofScutellaria baicalensisandAcacia catechuActs as a Dual Inhibitor of Cyclooxygenase and 5-Lipoxygenase to Reduce Inflammation

Abstract

A mixed extract containing two naturally occurring flavonoids, baicalin from Scutellaria baicalensis and catechin from Acacia catechu, was tested for cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) inhibition via enzyme, cellular, and in vivo models. The 50% inhibitory concentration for inhibition of both ovine COX-1 and COX-2 peroxidase enzyme activities was 15 microg/mL, while the mixed extract showed a value for potato 5-LOX enzyme activity of 25 microg/mL. Prostaglandin E2 generation was inhibited by the mixed extract in human osteosarcoma cells expressing COX-2, while leukotriene production was inhibited in both human cell lines, immortalized THP-1 monocyte and HT-29 colorectal adenocarcinoma. In an arachidonic acid-induced mouse ear swelling model, the extract decreased edema in a dose-dependent manner. When arachidonic acid was injected directly into the intra-articular space of mouse ankle joints, the mixed extract abated the swelling and restored function in a rotary drum walking model. These results suggest that this natural, flavonoid mixture acts via "dual inhibition" of COX and LOX enzymes to reduce production of pro-inflammatory eicosanoids and attenuate edema in an in vivo model of inflammation.

Baicalin attenuates oxygen-glucose deprivation-induced injury by inhibiting oxidative stress-mediated 5-lipoxygenase activation in PC12 cells

“…Unlike the typical 5-LOX inhibitor zileuton, baicalin did not inhibit baseline 5-LOX enzymatic activity but did inhibit the activity after OGD/recovery. Consistently, it has been reported that baicalin shows no inhibition of isolated potato 5-LOX [28] and non-stimulated rat cortical neurons [13] . Moreover, baicalin showed anti-oxidative activity because it reduced ROS production.…”

Antihyperglycemic and antinociceptive activity evaluation of ‘Khoyer’ prepared from boiling the wood of <i>Acacia catechu</i> in water

“…Gastric antiulcer activity has been demonstrated for aqueous extract of heartwood of the plant (Rajendra et al, 2011). Other activities reported for extract of whole plant are anti-pyretic, anti-diarrhoeal, hypotensive, hepatoprotective, anti-mycotic and anti-inflammatory activities (Sham et al, 1984;Ray and Thokchom, 2006;Burnett et al, 2007;Nagaraja et al, 2008). Seeds reportedly showed hypoglycemic activity in normal albino rats (Singh et al, 1976).…”

Assessment of antioxidant enzymes and free radical scavenging activity of selected medicinal plants

“…[12] Cinnamomum cassia (Family-Lauraceae) bark is attributed with numerous medicinal uses such as diaphoretic, antipyretic and analgesic. It is used as a carminative, cardiac stimulant, antioxidant, refrigerant and diuretic.…”