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The medicinal ferns of Polydiaceae and Davalliaceae species are called “Gusuibu” by Chinese physicians and used as antiaging dietary medicines. Our previous report revealed that Drynaria fortunei (Polydiaceae) protected against 6-hydroxydopamine (6-OHDA)-induced oxidative damage via the PI3K/AKT pathway in B35 neuroblastoma cells. The present study compares the antioxidant phytoconstituent contents and radical scavenging capacities of five Davalliaceae species. The further aim was to clarify the protective mechanism of Davallia mariesii (DM) against 6-OHDA-induced oxidative damage and apoptosis in B35 cells. The results show that Araiostegia perdurans (AP) and DM extracts have better radical scavenging capacities against 1,1-diphenyl-2-picryhydrazyl (DPPH) and reactive oxygen species (ROS) than other Davalliaceae species. However, only DM extract inhibited 6-OHDA autoxidation under cell-free systems and increased cell viability, compared to B35 cells solely exposed to 6-OHDA. DM extract decreased apoptosis and restored mitochondrial expression in 6-OHDA-treated B35 cells. Additional data indicated that DM extract decreased intracellular ROS and nitric oxide levels generated by 6-OHDA exposure. DM extract also restored glutathione (GSH) levels and the activities of glutathione peroxidase and reductase, and then decreased the elevated malondialdehyde (MDA) levels. Finally, DM extract regulated the protein expression of the caspase cascade and PI3K/AKT/GSK-3β pathways. These results suggest that the protective mechanism of DM extract against 6-OHDA-induced oxidative damage and apoptosis might be related to its radical scavenging capacity, maintaining the mitochondrial function to inhibit the Bcl-2/caspase cascade pathway and activating intracellular antioxidant defenses (GSH recycling, HO-1 and NQO-1) by modulating the activation of the PI3K/AKT/GSK-3β pathway.

Cholinergic dysfunction and oxidation stress are the dominant mechanisms of memory deficit in Alzheimer's disease (AD). This study describes how ferulic acid (FA) ameliorates cognitive deficits induced by mecamylamine (MECA), scopolamine (SCOP), central acetylcholinergic neurotoxin ethylcholine mustard aziridinium ion (AF64A) and amyloid β peptide (Aβ1-40). This study also elucidates the role of anti-oxidant enzymes and cholinergic marker acetylcholinesterase (AChE) in the reversal of FA from Aβ1-40-induced cognitive deficits in rats. At 100 mg/kg, FA attenuated impairment induced by MECA and SCOP plus MECA; however, this improvement was not blocked by the peripheral muscarinic receptor antagonist scopolamine methylbromide (M-SCOP). At 100 and 300 mg/kg, FA also attenuated the impairment of inhibitory passive avoidance induced by AF64A. Further, FA attenuated the performance impairment and memory deficit induced by Aβ1-40 in rats, as did vitamin E/C. FA reversed the deterioration of superoxide dismutase (SOD) and AChE activities, and the glutathione disulfide (GSSG) and glutathione (GSH) levels in the cortex and hippocampus. Vitamin E/C only selectively reversed deterioration in the hippocampus. We suggest that FA reduced the progression of cognitive deficits by activating central muscarinic and nicotinic receptors and anti-oxidant enzymes.

In Taiwan, new H1N1 monovalent vaccines without adjuvant and with MF59® adjuvant were used in the nationwide vaccination campaign beginning on November 1, 2009. From November 2009 through February 2010, the authors identified recipients of H1N1 vaccines who were diagnosed with adverse events of special interest (AESIs) in a large-linked safety database, and used the self-controlled case series (SCCS) method to examine the risk of each AESI in the 0–42 days after H1N1 vaccination. Of the 3.5 million doses of H1N1 vaccines administered and captured in the linked database, the SCCS analysis of Guillain-Barré syndrome (GBS) found an incidence rate ratio of 3.81 (95% confidence interval 0.43–33.85) within 0–42 days after nonadjuvanted H1N1 vaccination and no cases after MF59®-adjuvanted H1N1 vaccination. The risks of other AESIs were, in general, not increased in any of the predefined postvaccination risk periods and age groups. The databases and infrastructure created for H1N1 vaccine safety evaluation may serve as a model for safety, effectiveness and coverage studies of licensed vaccines in Taiwan.