The main pathologic changes of the Parkinson’s disease (PD) is dopaminergic (DA) neurons lost. Apoptosis was one of the important reasons involved in the DA lost. Our previous study found a fucoidan fraction sulfated heterosaccharide (UF) had neuroprotective activity. The aim of this study was to clarify the mechanism of UF on DA neurons using human dopaminergic neuroblastoma (SH-SY5Y) cells a typical as a PD cellular model. Results showed that UF prevented MPP⁺-induced SH-SY5Y cells apoptosis and cell death. Additionally, UF pretreated cells increased phosphorylation of Akt, PI3K and NGF, which means UF-treated active PI3K–Akt pathway. Moreover, UF treated cells decreased the expression of apoptosis-associated protein, such as the ratio of Bax/Bcl-2, GSK3β, caspase-3 and p53 nuclear induced by MPP⁺. This effect was partially blocked by PI3K inhibitor LY294002. Our data suggested that protective effect of UF against MPP⁺-induced SH-SY5Y cells death by affecting the PI3K–Akt pathway. These findings contribute to a better understanding of the critical roles of UF in treating PD and may elucidate the molecular mechanisms of UF effects in PD.

Nephrotic syndrome (NS) is a clinical syndrome with a variety of causes, mainly characterized by heavy proteinuria, hypoalbuminemia, and edema. At present, identification of effective and less toxic therapeutic interventions for nephrotic syndrome remains to be an important issue. In this study, we isolated fucoidan from Saccharina japonica and prepared its depolymerized fragment by oxidant degradation. Fucoidan and its depolymerized fragment had similar chemical constituents. Their average molecular weights were 136 and 9.5 kDa respectively. The effect of fucoidan and its depolymerized fragment on adriamycin-induced nephrotic syndrome were investigated in a rat model. The results showed that adriamycin-treated rats had heavy proteinuria and increased blood urea nitrogen (BUN), serum creatinine (SCr), total cholesterol (TC), and total triglyceride (TG) levels. Oral administration of fucoidan or low-molecular-weight fucoidan for 30 days could significantly inhibit proteinuria and decrease the elevated BUN, SCr, TG, and TC level in a dose-dependent manner. At the same dose (100 mg/kg), low-molecular-weight fucoidan had higher renoprotective activity than fucoidan. Their protective effect on nephrotic syndrome was partly related to their antioxidant activity. The results suggested that both fucoidan and its depolymerized fragment had excellent protective effect on adriamycin-induced nephrotic syndrome, and might have potential for the treatment of nephrotic syndrome.

Nowadays, natural polysaccharides-based hydrogels have achieved promising results as dressings to promote skin healing. In the present study, we prepared a novel hydrogel nanocomposite with poly(vinyl alcohol) (PVA) and sulfated heterosaccharide (UF), named UPH. The SEM results showed that the UPH had dense porous structures with a high porosity and a specific surface area. The UPH had a good swelling property, which can effectively adsorb exudate and keep the wound moist. The in vitro experiments results showed that the UPH was non-cytotoxic and could regulate the inflammatory response and promote the migration of fibroblasts significantly. The phenotypic, histochemistry, and Western blot analyses showed UPH treatment accelerated the wound healing and recovery of skin tissue at wound sites in a C57BL/6 mouse model. Furthermore, the UPH could promote the inflammation process to onset earlier and last shorter than that in a normal process. Given its migration-promoting ability and physicochemical properties, the UPH may provide an effective application for the treatment and management of skin wounds.