Fucus vesiculosus and Ascophyllum nodosum Ameliorate Liver Function by Reducing Diet-Induced Steatosis in Rats

Abstract

The Asian coastal communities have used the brown seaweeds Fucus vesiculosus and Ascophyllum nodosum since ancient times. Recently, some in vitro and in vivo studies have demonstrated their abilities in reducing risk factors for metabolic syndrome. Here, we analyzed the protective effect of a phytocomplex extracted from these seaweeds on the deposition of fat in the liver after the administration of a high-fat diet (HFD) to rats for five weeks. The administration of F. vesiculosus and A. nodosum led to significant reductions in microvescicular steatosis and plasma biochemical and lipid parameters, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total and conjugated bilirubin, and triglycerides. Furthermore, the postprandial glycemic peak was delayed and significantly reduced (p < 0.01) by the algal extract administration. In conclusion, this extract is effective in reducing microvescicular steatosis and improving glycemic control, thereby lowering the risk of nonalcoholic fatty liver disease, obesity, and diabetes, diseases related to the consumption of fat and sugar-enriched diets.

Brown Seaweeds for the Management of Metabolic Syndrome and Associated Diseases

“…CVDs represent the main cause of death worldwide, with 422.7 million cases (according to a 2015 report), and approximately 18 million deaths [ 22 ]. Moreover, it has been estimated that hypertension is diagnosed in 40% of adults (aged >25 years), and the annual expenses due to the patients’ management and the loss of productivity due to heart disease in the USA are estimated to be around 200 billion dollars at least [ 4 ]. Noteworthy, Japanese and Korean people have one of the longest average life expectancies and display a lower risk of developing hypertension and cardiovascular diseases than other populations [ 23 , 24 ].…”

“…Several studies have demonstrated that many phlorotannins are also able to increase the glucose uptake by skeletal muscles and inhibit the protein tyrosine phosphatase 1B (PTP1B), which regulates the leptin and insulin signaling pathways, thereby improving insulin sensitivity [ 19 , 94 ]. Accordingly, many studies have reported that A. nodosum and F. vesiculosus display antidiabetic properties due to their phenolic-rich composition, and are able to decrease the postprandial blood glucose levels and insulin peak in various animal models of MS-related disorders [ 4 , 95 , 96 ]. Moreover, since postprandial “hyperglycemic spikes” could induce micro- and macro-vascular diseases, it is reasonable to hypothesize that these algal phlorotannins could be beneficial for CVD patients [ 97 ].…”

“…Many studies investigating the activity of brown seaweeds are performed by in vitro or in vivo evaluations on cell lines or animal models, respectively, providing valuable information regarding the identification of the bioactive components responsible for the effect and the signaling pathways involved. For example, a number of in vivo animal studies have demonstrated the anti-diabetic and hypoglycemic efficacy of brown seaweeds [ 4 , 95 , 96 , 166 , 167 ]. The principal mechanism involved in this activity is the inhibition of digestive enzymes (e.g., α-amylase, α-glucosidase, lipase, PTP1B), which causes a reduction in dietary fat and glucose absorption, and the hepatic gluconeogenesis.…”

“…Although these drugs can be helpful, many of them lead to serious side-effects, and their efficacy could be reduced or lost with chronic administration. Thus, nutritional interventions have been proposed to reduce the risk of MS by preventing and alleviating chronic dietary-associated disorders [ 4 , 5 ].…”

Fucoidan Induces Apoptosis of HT-29 Cells via the Activation of DR4 and Mitochondrial Pathway

“…Fucoidan is a water-soluble heteropolysaccharide, derived mostly from brown algae, such as Fucus vesiculosus (Figure 1) [1][2][3][4][5]. Recent studies have shown that the research on fucoidan mainly focuses on two aspects-one is to explore ways to increase the yield of fucoidan [6][7][8][9], while the other is to explore the various pharmacological activities of fucoidan [10][11][12], including anti-inflammatory [13,14], anti-tumor, anti-virus, hypolipidemic, antithrombotic, and so on [15], but less research exists on its mechanism.…”