Feruloylated oligosaccharides ameliorate MPTP-induced neurotoxicity in mice by activating ERK/CREB/BDNF/TrkB signalling pathway.

BACKGROUND: Feruloylated oligosaccharides (FOs) are natural esterification products of ferulic acid and oligosaccharides. STUDY DESIGN: In this study, we examined whether FOs contribute to the ensured survival of nigrostriatal dopamine neurons and inhibition of neuroinflammation in Parkinson's disease (PD). METHODS: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg) was injected intraperitoneally into mice to establish a Parkinson's disease (PD) mouse model. FOs (15 and 30 mg/kg) were orally administered daily to the MPTP-treated mice. The rotarod test, balance beam test, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), quantitative PCR (qPCR), and western blot analyses were performed to examine the neuroprotective effects of FOs on MPTP-treated mice. RESULTS: Our study indicated that FOs increased the survival of dopamine neurons in the substantia nigra pars compacta (SNc) of the MPTP-treated mice. The neuroprotective effects of FOs were accompanied by inhibited glial activation and reduced inflammatory cytokine production. The mechanistic experiments revealed that the neuroprotective effects of FOs might be mediated through the activation of the ERK/CREB/BDNF/TrkB signalling pathway. CONCLUSION: This study provides new insights into the mechanism underlying the anti-neuroinflammatory effect of phytochemicals and may facilitate the development of dietary supplements for PD patients. Our results indicate that FOs can be used as potential modulators for the prevention and treatment of PD.

Antibacterial and antibiofilm activities of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) against periodontopathic bacteria.

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are two major omega-3 polyunsaturated fatty acids (n-3 PUFAs) with antimicrobial properties. In this study, we evaluated the potential antibacterial and antibiofilm activities of DHA and EPA against two periodontal pathogens, Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum). MTT assay showed that DHA and EPA still exhibited no cytotoxicity to human oral tissue cells when the concentration came to 100 µM and 200 µM, respectively. Against P. gingivalis, DHA and EPA showed the same minimum inhibitory concentration (MIC) of 12.5 µM, and a respective minimum bactericidal concentration (MBC) of 12.5 µM and 25 µM. However, the MIC and MBC values of DHA or EPA against F. nucleatum were both greater than 100 µM. For early-stage bacteria, DHA or EPA displayed complete inhibition on the planktonic growth and biofilm formation of P. gingivalis from the lowest concentration of 12.5 µM. And the planktonic growth of F. nucleatum was slightly but not completely inhibited by DHA or EPA even at the concentration of 100 µM, however, the biofilm formation of F. nucleatum at 24 h was significantly restrained by 100 µM EPA. For exponential-phase bacteria, 100 µM DHA or EPA completely killed P. gingivalis and significantly decreased the viable counts of F. nucleatum. Meanwhile, the morphology of P. gingivalis was apparently damaged, and the virulence factor gene expression of P. gingivalis and F. nucleatum was strongly downregulated. Besides, the viability and the thickness of mature P. gingivalis biofilm, together with the viability of mature F. nucleatum biofilm were both significantly decreased in the presence of 100 µM DHA or EPA. In conclusion, DHA and EPA possessed antibacterial activities against planktonic and biofilm forms of periodontal pathogens, which suggested that DHA and EPA might be potentially supplementary therapeutic agents for prevention and treatment of periodontal diseases.

Effects of amycenone on serum levels of tumor necrosis factor-α, interleukin-10, and depression-like behavior in mice after lipopolysaccharide administration.

Accumulating evidence suggests that inflammation plays a role in the pathophysiology of depression and that anti-inflammatory substances have antidepressant effects. Amycenone is obtained from extracts of the Yamabushitake (Hericium erinaceum). The purpose of this study is to examine whether amycenone shows anti-inflammatory and antidepressant effects in an inflammation-induced mouse model of depression. First, we examined the effects of amycenone on the serum levels of the pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α), and the anti-inflammatory cytokine, interleukin-10 (IL-10), after intraperitoneal administration of the bacterial endotoxin lipopolysaccharide (LPS). Oral administration of amycenone (50, 100, or 200mg/kg) markedly blocked an increase in the serum TNF-α levels after a single administration of LPS (0.5mg/kg). Furthermore, amycenone (200mg/kg) markedly increased the serum IL-10 levels by a single administration of LPS (0.5mg/kg). Next, we examined the effects of amycenone on depression-like behaviors in the tail-suspension test (TST) and forced swimming test (FST). Pretreatment with amycenone (200mg/kg) significantly attenuated LPS (0.5mg/kg)-induced increase of the immobility time by the TST and FST, indicating antidepressant effects of amycenone. In addition, oral administration of paroxetine (30mg/kg) showed anti-inflammatory and antidepressant effects in the same model. These findings suggest that amycenone has antidepressant effects in LPS-induced inflammation model of depression. Therefore, amycenone could represent a potential supplement to prevent inflammation-related depression.