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.

Emerging roles of long non-coding RNA in depression

Depression is the second most common psychiatric disorder, affecting more than 340 million people of all ages worldwide. However, the mechanisms underlying the development of depression remain unclear, and existing antidepressants may cause clinical dependence and toxic side effects. Recently, emerging evidence from the fields of neuroscience, genetics, and genomics supports the modulatory role of long non-coding RNA (lncRNA) in depression. LncRNAs may mediate the pathogenesis of depression through multiple pathways, including regulating neurotransmitters and neurotrophic factors, affecting synaptic conduction, and regulating the ventriculo-olfactory neurogenic system. In addition, relying on genome-wide association study and molecular biological experiment, the possibility of lncRNA as a potential biomarker for the differential diagnosis of depression and other mental illnesses, including schizophrenia and anxiety disorders, is gradually being revealed. Thus, it is important to explore whether lncRNAs are potential therapeutic targets and diagnostic biomarkers for depression. Here, we summarize the genesis and function of lncRNAs and discuss the aberrant expression and functional roles of lncRNAs in the development, diagnosis, and therapy of depression, as well as the deficiencies and limitations of these studies. Moreover, we established a lncRNA-miRNA-mRNA-pathway-drug network of depression through bioinformatics analysis methods to deepen our understanding of the relationship between lncRNA and depression, promoting the clinical application of epigenetic research.

Oral coniferyl ferulate attenuated depression symptoms in mice via reshaping gut microbiota and microbial metabolism

The gut microbiome is known to be involved in depression development. Thus, phytochemicals changing gut microbiota may alleviate depression-like behaviors. Coniferyl ferulate (CF) is a long studied natural product and known to alleviate psychiatric disorders. However, its mechanism of action remains unclear. In this experimental study, oral administration of 50 mg kg^-1 CF once daily attenuated weight loss and depression-like and anxiety-like behaviors induced by chronic unpredicted mild stress (CUMS) in mice. Four weeks of CF administration significantly ameliorated colonic inflammation, lowered the levels of IL-6, IL-1β, and TNF-α, and restructured the gut microbiome, and microbial metabolism. Intestinal microbiota can impact the development and function of the brain via the microbiota-gut-brain axis. Therefore, oral administration of CF is a promising nutritional strategy to treat CUMS-induced depression via the regulation of microbiota and microbial metabolism.

Feruloylated Oligosaccharides Alleviate Central Nervous Inflammation in Mice Following Spinal Cord Contusion

As one of the empirical models of the chronic central inflammatory response, a spinal cord injury (SCI) deteriorates the neuronal survival and results in irreversible motor and sensory dysfunction below the injury area. Our previous studies have reported that maize bran feruloylated oligosaccharides (FOs) exert significant anti-inflammatory activities both in diabetes and colitis. However, no direct evidence of FOs alleviating central nervous inflammation was stated. This study aimed to investigate the therapeutic effect of FOs on SCI and its potential mechanism. Our results indicated that 4 weeks of FO administration effectively mitigated the inflammatory response via decreasing the number of microglia (labelled with Iba1), result in the expression of IL-1α, IL-2, IL-6, IL-18 and TNF-α downregulating, but the level of IL-10 and BDNF increases in the injured spinal cord. Moreover, FOs enhanced neuronal survival, ameliorated the scar cavities, and improved behaviors, including Basso mouse scale (BMS) scores and the gait of mice after SCI. Together, these results demonstrated that administration of FOs showed superior functional recovery effects in a SCI model. Also, FOs may modulate inflammatory activities by regulating the expression of proinflammatory factors, decreasing the production of inflammatory cells, and promoting functional recovery through the MAPK pathway following SCI.

A review of antibiotics, depression, and the gut microbiome

Emerging evidence indicates that disruption of the intestinal flora play an important role in the pathogenesis of depression. As one of the causes of such disturbances, the role of antibiotics in depression risk is gradually being revealed. Herein, we review recent findings showing that the use of both single and multiple antibiotic regimens may be related to depression by changing the gut microbiota and the brain-gut axis. Based on recent discoveries, we also suggest that several brain-gut interactive mechanisms (particularly those involving nerve and glial cells, neurotransmitters, brain neurotrophic factors, inflammatory factors, short-chain fatty acids, circulating metabolites, blood-brain barrier, and oxidative stress) may help understand the effects of antibiotics on intestinal flora and its relationship with depression.