Brown Algae Dictyopteris divaricata Attenuates Adipogenesis by Modulating Adipocyte Differentiation and Promoting Lipolysis through Heme Oxygenase-1 Activation in 3T3-L1 Cells.

The present study aims to explore the probable anti-adipogenesis effect of Dictyopteris divaricata (D. divaricata) in 3T3-L1 preadipocytes by regulating heme oxygenase-1 (HO-1). The extract of D. divaricata retarded lipid accretion and decreased triglyceride (TG) content in 3T3-L1 adipocytes but increased free glycerol levels. Treatment with the extract inhibited lipogenesis by inhibiting protein expressions of fatty acid synthase (FAS) and lipoprotein lipase (LPL), whereas lipolysis increased by activating phosphorylation of hormone-sensitive lipase (p-HSL) and AMP-activated protein kinase (p-AMPK). The extract inhibited adipocyte differentiation of 3T3-L1 preadipocytes through down-regulating adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP1). This is attributed to the triggering of Wnt/ß-catenin signaling. In addition, this study found that treatment with the extract activated HO-1 expression. Pharmacological approaches revealed that treatment with Zinc Protoporphyrin (ZnPP), an HO-1 inhibitor, resulted in an increase in lipid accumulation and a decrease in free glycerol levels. Finally, three adipogenic transcription factors, such as PPARγ, C/EBPα, and SREBP1, restored their expression in the presence of ZnPP. Analysis of chemical constituents revealed that the extract of D. divaricata is rich in 1,4-benzenediol, 7-tetradecenal, fucosterol, and n-hexadecanoic acid, which are known to have multiple pharmacological properties.

Effect of crude polysaccharide from seaweed, Dictyopteris divaricata (CDDP) on gut microbiota restoration and anti-diabetic activity in streptozotocin (STZ)-induced T1DM mice.

Type-1 Diabetes Mellitus (T1DM) is regarded as a multifunctional, immune-related disease which causes massive destruction of islet ß-cells in pancreas resulting in hyperglycemic, hypoinsulinemia and hyperlipidimic conditions. The aim of the present study, was to investigate the hypothesis that streptozotocin (STZ)-induced T1DM in Balb/c mice when treated with crude polysaccharide from seaweed, Dictyopteris divaricata (CDDP) depicts improvement in diabetes-related symptoms. Treatment with CDDP resulted in decreased body weight loss, improved food consumption and water intake disbalances. The CDDP effectively improved fasting blood glucose, oral glucose tolerance (OGTT), serum insulin, insulin secretion, rejuvenation of ß-cells mass, serum lipid profile and pro-inflammatory cytokines levels. Additionally, treatment with CDDP increased the population of beneficial bacteria such as Firmicutes, Bacteroidetes and Lactobacillus at phylum, family and genus levels by 16S rRNA sequencing. Furthermore, immunohistological examination confirmed that CDDP reduces the inflammation and restored the structural morphology of colon and upraised the levels of insulin receptor substrate-1 (IRS-1), Mucin-2 (MUC-2) and tight-junction proteins (TJs) whereby maintaining the gut structures and barrier permeability. Thus, the above presented data, highlights the safe and therapeutic effects of crude polysaccharide (CDDP) from D. divaricata in the treatment and restoration of T1DM disorders and can be used as a food supplement alternative to diabetes medicine.

A new epoxy-cadinane sesquiterpene from the marine brown alga Dictyopteris divaricata.

A new epoxy-cadinane sesquiterpene, 4beta,5beta-epoxycadinan-1beta-ol (1), and six known cadinane sesquiterpenes: cadinan-1,4,5-triol (2), 4alpha,5beta-dihydroxycubenol (3), cubenol (4), cadinan-3-ene-1,5-diol (5), cubenol-3-one (6), and torreyol (7), were isolated from a sample of marine brown alga Dictyopteris divaricata collected off the coast of Yantai (China). Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with literature data.

Brominated selinane sesquiterpenes from the marine brown alga Dictyopteris divaricata.

Two new brominated selinane sesquiterpenes, 1-bromoselin-4(14),11-diene (1) and 9-bromoselin-4(14),11-diene (2), one known cadinane sesquiterpene, cadalene (3), and four known selinane sesquiterpenes, alpha-selinene (4), beta-selinene (5), beta-dictyopterol (6), and cyperusol C (7), were isolated from a sample of marine brown alga Dictyopteris divaricata collected off the coast of Yantai (China). Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with literature data.

Extraction, characterization and biological activity of sulfated polysaccharides from seaweed Dictyopteris divaricata.

Dictyopteris divaricata is a kind of important brown algae with many biological activities. It has been receiving more and more attention, yet there are rarely studies done on its polysaccharides. In this study, the optimum extraction and biological activity of seaweed polysaccharides from Dictyopteris divaricata (DDSP) were investigated. Response surface methodology (RSM), based on a three-level, three-variable Box-Behnken design (BBD), was employed to obtain the best possible combinations for maximum polysaccharides yield. The optimum extraction conditions were as follows: liquid-solid ratio of 110 mL/g, extraction time of 6 h and extraction temperature of 100 °C. Under these conditions, the experimental yield was 3.05%, which was in close agreement with the predicted value of 3.15%. The average molecular weight of DDSP was 58.05 kDa. Gas chromatograph (GC) results showed that DDSP was composed of fucose, xylose, mannose, glucose and galactose with the corresponding molar ratio of 4.45:2.74:1.00:2.94:1.35. Biological activity showed that DDSP exhibited strong antioxidant activity in vitro and possessed the potential on stimulating immune response of RAW264.7 cells. So DDSP can be used as a natural ingredient in functional foods.