The Phytocomplex from Fucus vesiculosus and Ascophyllum nodosum Controls Postprandial Plasma Glucose Levels: An In Vitro and In Vivo Study in a Mouse Model of NASH

Abstract

Edible seaweeds have been consumed by Asian coastal communities since ancient times. Fucus vesiculosus and Ascophyllum nodosum extracts have been traditionally used for the treatment of obesity and several gastrointestinal diseases. We evaluated the ability of extracts obtained from these algae to inhibit the digestive enzymes α-amylase and α-glucosidase in vitro, and control postprandial plasma glucose levels in a mouse model of non-alcoholic steatohepatitis (NASH); a liver disease often preceding the development of Type 2 diabetes (T2DM). This model was obtained by the administration of a high-fat diet. Our results demonstrate that these algae only delayed and reduced the peak of blood glucose (p < 0.05) in mice fed with normal diet, without changing the area under the blood glucose curve (AUC). In the model of NASH, the phytocomplex was able to reduce both the postprandial glycaemic peak, and the AUC. The administration of the extract in a diet particularly rich in fat is associated with a delay in carbohydrate digestion, but also with a decrease in its assimilation. In conclusion, our results indicate that this algal extract may be useful in the control of carbohydrate digestion and absorption. This effect may be therapeutically exploited to prevent the transition of NASH to T2DM.

Ascophyllum nodosum and Fucus vesiculosus on glycemic status and on endothelial damage markers in dysglicemic patients

“…The positive results on glycemic control observed in our study can be due to the inhibiting action of the polyphenolic composition (extracted from A. nodosum and F. vesiculosus) towards enzymatic activities, in an acarbose-like mechanism. The ability of a phytocomplex obtained from these algae to inhibit both enzymes has already been demonstrated by Roy et al (2011) and confirmed by Gabbia et al (2017) who showed that the administration of the extract in a diet particularly rich in fat in mice is associated with a delay in carbohydrate digestion but also with a decrease in its assimilation. Reducing PPG with the nutraceutical, probably, leads to a minor work for the β-cells and a consequent longer preservation of β-cell function.…”

Seasonal variation in biopharmaceutical activity and fatty acid content of endemic Fucus virsoides algae from Adriatic Sea

“…Furthermore, Kellog et al (33), showed that the ethyl acetate fraction of Alaskan Fucus distichus, that also had the highest total phenolic content, had the highest α-glucosidase inhibitory effect. It was previously reported that fucoidan from F. vesiculosus and F. vesiculosus extract alone inhibited this enzyme (34,35). Su et al (36) have also shown that both saturated and unsaturated pure fatty acids inhibited α-glucosidase stronger than acarbose.…”

Seaweeds as nutraceuticals for health and nutrition

“…The in vivo anti-diabetic efficacy of seaweed has been shown in many animal studies (Gabbia et al 2017;Roy et al 2011;Song et al 2018;Zhao et al 2018). In human clinical trials, daily supplementation with Undaria pinnatifida and Sacchariza polyschides (as Gigantea bulbosa) balances blood glucose levels, decreases serum triglyceride concentrations, and increases high-density lipoprotein cholesterol in subjects with type 2 diabetes (Kim et al 2008).…”