Antinociceptive, anti-inflammatory and hypoglycemic activities of the ethanolic Sm. flower extract in adult zebrafish ().

Sm. belongs to the family Turneraceae and is found in Brazil. The present study evaluated the antinociceptive, anti-inflammatory, and hypoglycemic potential of flower extract (EtFloTsu) in zebrafish (). The total phenol and flavonoid contents of EtFloTsu were determined and identified using the Folin Ciocalteu reagent and aluminum chloride (AlCl), respectively. The constituents of the extract were identified by HPLC-DAD, and the antioxidant activity (DPPH) was determined, toxicity in brine shrimp, and acute toxicity of 96 h in adult zebrafish. In addition, adult zebrafish (n = 6/fish) were treated orally with EtFloTsu (4, 20, or 40 mg/kg; vo) and subjected to formalin-induced nociception tests (with its possible mechanism of action with camphor), carrageenan-induced inflammation, and D-glucose-induced hyperglycemia (111 mM). Oxidative stress in the liver and brain tissues was assessed. EtFloTsu showed high levels of phenolic and flavonoid compounds with antioxidant activity. The phytochemicals chlorogenic acid, luteolin-7-o-glucoside, vitexin, and apigenin-7-o-glucoside were also identified in EtFloTsu. The synergism between these constituents was possibly responsible for the antinociceptive (via TRPA1), anti-inflammatory, and hypoglycemic effects of EtFloTsu in adult zebrafish, without causing toxicity in animals. Therefore, flowers have therapeutic agents that could treat pain, inflammation, diabetes, and related complications.Communicated by Ramaswamy H. Sarma.