Effects of six weeks consumption of coconut milk oil on vascular functions and fasting blood glucose and lipid profile in middle-aged male rats

Abstract

Background: Coconut milk consumption in middle-aged male rats can cause increased blood vessel endothelial nitric oxide synthase (eNOS) and cystathionine-γ-lyase (CSE) protein expression, and decreased fasting blood glucose.Objective: The present study aimed to investigate whether coconut milk oil (CO), the major constituents of the coconut milk, was responsible for those effects.Methods: CO was isolated from dried fresh coconut milk and gavaged (1 and 3 ml/kg) to middle-aged male rats for 6 weeks. Blood biochemistry, lipid profile and vascular functions were investigated.Results: In comparison to a distilled water control group, no differences were observed in any of the parameters studied in the group fed 1 ml/kg of CO except for an increase in retroperitoneal fat accumulation. Feeding 3 ml/kg of CO caused decreased fasting blood glucose, plasma alkaline phosphatase and blood urea nitrogen and liver cell lipid accumulation, but increased retroperitoneal fat tissue. It also caused decreased maximal contractile response of endothelium-intact thoracic aortic rings to phenylephrine although the effect disappeared in the presence of N-nitro-L-arginine (L-NA) or removal of the endothelium. DL-propargylglycine together with L-NA caused a higher contraction to phenylephrine in the CO-treated groups than in the control group. It also caused an increase in vasodilatation to acetylcholine, but not to glyceryl trinitrate, of the phenylephrine pre-contracted aortic rings. CO treatment caused increased vascular wall eNOS and CSE protein expression.Conclusion: CO at a dose of 3 ml/kg causes some decrease in cardiovascular risk factors in middle-aged male rats, although the amount of CO consumption should be limited as it caused an increase in retroperitoneal fat.

Nutritional and therapeutic benefits of coconut milk and its potential as a plant-based functional yogurt alternative: a review

“…This leads to increased production of NO and H2S from blood vessels, resulting in reduced vasocontraction to phenylephrine and improved relaxation to acetylcholine. These findings suggest positive effects on cardiovascular markers [39][40][41] . It is important to note that these processes take place when the fat intake is wholesome (i.e., not refined into specific components) and under appropriate circumstances (i.e.…”

Decreased body-fat accumulation and increased vasorelaxation to glyceryl trinitrate in middle-aged male rats following six-weeks consumption of coconut milk protein

“…Meanwhile our research group studied middle-aged male rats and found that the consumption of pure dried fresh coconut milk caused up-regulation of blood vessel endothelial nitric oxide synthase (eNOS) and cystathionine γ-lyase (CSE) protein expression, which resulted in an attenuation of the contractile response to phenylephrine and potentiate relaxation to acetylcholine on the rats' thoracic aortic rings, with a decreased fasting plasma glucose level (Jansakul et al, 2018). Further, these effects were very similar to those resulting from the consumption of dried fresh coconut milk oil except that the retroperitoneal fat accumulation was increased (Naphatthalung et al, 2019), which indicates that there must be other active components in the coconut milk that counteract fat accumulation from the coconut milk oil.…”