RESUMO
The α7-nicotinic acetylcholine receptor (α7-nAChR) is a recognized target for the treatment of dementia associated with aging and certain developmental disorders. This study evaluates memory improvement in a rat model by the effects of polyunsaturated fatty acids EPA and DHA mediated by α7-nAChR, as well as identifying the minimum dose of EPA/DHA required to generate an effect in the improvement of cognition through α7-nAChR in rats. The modiï¬ed Y-maze and object recognition behavioral tests were performed in scopolamine-induced amnesic rats, in order to study the effects of long-term supplementation (10, 15, 30, and 60â mg/kg) of the two polyunsaturated fatty acids in improving cognitive impairment. Cognitive enhancement by EPA and DHA is mediated through α7-nAChRs, as evidenced by memory recovery after treatment with a selective α7-nAChR antagonist, methyllycaconitine (MLA). Tacrine, a centrally active acetylcholinesterase inhibitor, and PNU282987, an α7-nAChR agonist, are employed as reference standards. Our data demonstrate that 15â mg/kg EPA and DHA can affect cholinergic neurotransmission positively through memory and cognition and, thus, can exert a beneficial action on learning and memory deficits.
Assuntos
Acetilcolinesterase , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Cognição , Ácidos Graxos Insaturados/farmacologia , Agonistas Nicotínicos/farmacologia , Agonistas Nicotínicos/uso terapêutico , RatosRESUMO
Metabolic syndrome is a condition whose incidence has been increasing around the world. It promotes a metabolic state of chronic systemic inflammation, correlated to cellular stress and genetic mutations, and subsequently with deadly chronic diseases, such as type 2 diabetes mellitus, cardiovascular diseases, and cancer. A randomized placebo-controlled study (n = 156) was conducted to determine the effects of consuming an enriched bread with 0.05% of a 1:1 mixture of (-)-epicatechin and quercetin on anthropometric and biochemical parameters of the participants. As a result, total cholesterol, LDL-cholesterol, total triglycerides, and fasting plasma glucose significantly decreased after three months of daily enriched bread consumption. Nuclear abnormalities in buccal epithelium cells also decreased (15.8 ± 3.2 down to 8.3 ± 1.0), showing a genoprotective effect. The antioxidant properties of these compounds were observed by monitoring changes in the cytoplasmic redox tone of intact Caco-2 cells expressing HyPer, a fluorescent redox biosensor. The combination of (-)-epicatechin and quercetin changes the cytoplasmic redox ambient in living cells and significantly improves biochemical parameters related to metabolic syndrome, and decreases the number of cell abnormalities in buccal epithelium cells of patients.