Targeting of KOR by famotidine promotes OPC maturation differentiation and CNS remyelination via STAT3 signaling pathway.

This study aims to identify FDA-approved drugs that can target the kappa-opioid receptor (KOR) for the treatment of demyelinating diseases. Demyelinating diseases are characterized by myelin sheath destruction or formation that results in severe neurological dysfunction. Remission of this disease is largely dependent on the differentiation of oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes (OLGs) in demyelinating lesions. KOR is an important regulatory protein and drug target for the treatment of demyelinating diseases. However, no drug targeting KOR has been developed due to the long clinical trials for drug discovery. Here, a structure-based virtual screening was applied to identify drugs targeting KOR among 1843 drugs of FDA-approved drug libraries, and famotidine was screen out by its high affinity cooperation with KOR as well as the clinical safety. We discovered that famotidine directly promoted OPC maturation and remyelination using the complementary in vitro and in vivo models. Administration of famotidine was not only effectively enhanced CNS myelinogenesis, but also promoted remyelination. Mechanically speaking, famotidine promoted myelinogenesis or remyelination through KOR/STAT3 signaling pathway. In general, our study provided evidence of new clinical applicability of famotidine for the treatment of demyelinating diseases for which there is currently no effective therapy.

Therapeutic effects and mechanisms of isoxanthohumol on DSS-induced colitis: regulating T cell development, restoring gut microbiota, and improving metabolic disorders.

Ulcerative colitis (UC) is a severe hazard to human health. Since pathogenesis of UC is still unclear, current therapy for UC treatment is far from optimal. Isoxanthohumol (IXN), a prenylflavonoid from hops and beer, possesses anti-microbial, anti-oxidant, anti-inflammatory, and anti-angiogenic properties. However, the potential effects of IXN on the alleviation of colitis and the action of the mechanism is rarely studied. Here, we found that administration of IXN (60 mg/kg/day, gavage) significantly attenuated dextran sodium sulfate (DSS)-induced colitis, evidenced by reduced DAI scores and histological improvements, as well as suppressed the pro-inflammatory Th17/Th1 cells but promoted the anti-inflammatory Treg cells. Mechanically, oral IXN regulated T cell development, including inhibiting CD4+ T cell proliferation, promoting apoptosis, and regulating Treg/Th17 balance. Furthermore, IXN relieved colitis by restoring gut microbiota disorder and increasing gut microbiota diversity, which was manifested by maintaining the ratio of Firmicutes/Bacteroidetes balance, promoting abundance of Bacteroidetes and Ruminococcus, and suppressing abundance of proteobacteria. At the same time, the untargeted metabolic analysis of serum samples showed that IXN promoted the upregulation of D-( +)-mannose and L-threonine and regulated pyruvate metabolic pathway. Collectively, our findings revealed that IXN could be applied as a functional food component and served as a therapeutic agent for the treatment of UC.

Peroxisom proliferator-activated receptor-γ coactivator-1α in neurodegenerative disorders: A promising therapeutic target.

Neurodegenerative disorders (NDDs) are characterized by progressive loss of selectively vulnerable neuronal populations and myelin sheath, leading to behavioral and cognitive dysfunction that adversely affect the quality of life. Identifying novel therapies that attenuate the progression of NDDs would be of significance. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), a widely expressed transcriptional regulator, modulates the expression of genes engaged in mitochondrial biosynthesis, metabolic regulation, and oxidative stress (OS). Emerging evidences point to the strong connection between PGC-1α and NDDs, suggesting its positive impaction on the progression of NDDs. Therefore, it is urgent to gain a deeper and broader understanding between PGC-1α and NDDs. To this end, this review presents a comprehensive overview of PGC-1α, including its basic characteristics, the post-translational modulations, as well as the interacting transcription factors. Secondly, the pathogenesis of PGC-1α in various NDDs, such as Alzheimer's (AD), Parkinson's (PD), and Huntington's disease (HD) is briefly discussed. Additionally, this study summarizes the underlying mechanisms that PGC-1α is neuroprotective in NDDs via regulating neuroinflammation, OS, and mitochondrial dysfunction. Finally, we briefly outline the shortcomings of current NDDs drug therapy, and summarize the functions and potential applications of currently available PGC-1α modulators (activator or inhibitors). Generally, this review updates our insight of the important role of PGC-1α on the development of NDDs, and provides a promising therapeutic target/ drug for the treatment of NDDs.

2', 4'-Dihydroxy-2,3-dimethoxychalcone: A pharmacological inverse agonist of RORγt ameliorating Th17-driven inflammatory diseases by regulating Th17/Treg.

Multiple sclerosis, inflammatory bowel disease and organ transplant rejection are related to Th17 cell development and inflammatory respond. RORγt, a specific transcription factor regulating Th17 cell differentiation, is a pivotal target for the treatment of diseases. However, the clinical application of RORγt inverse agonists reported so far has been hindered due to limited efficacy and toxic side effects. Plant-derived natural products with drug-like properties and safety are wide and valuable resources for candidate drug discovery. Herein, structure-based virtual screening was used to find out 2',4'-Dihydroxy-2,3-dimethoxychalcone (DDC), a chalcone derivative rich in plants and food, located in the binding pocket of RORγt and targeted to inhibit RORγt activity. DDC repressed murine Th17 differentiation and promoted Treg differentiation remarkably in a dose-dependent manner. In addition, DDC treatment improved experimental autoimmune encephalomyelitis recovery, ameliorated experimental colitis severity, and prevented graft rejection significantly. Mechanically, DDC indirectly stabilized Foxp3 expression by inhibiting RORγt activity and the expression of its target gene profile in vitro and in vivo, which realized its regulation of Th17/Treg balance. In conclusion, our study provides a scientific basis that DDC, as an inverse agonist of RORγt with simple structure, rich sources, low cost, high efficiency, and low toxicity, has great potential for the development of a novel effective immunomodulator for the treatment of Th17-mediated inflammatory diseases.

Baicalin Promotes CNS Remyelination via PPARγ Signal Pathway.

BACKGROUND AND OBJECTIVES: Demyelinating diseases in the CNS are characterized by myelin sheath destruction or formation disorder that leads to severe neurologic dysfunction. Remission of such diseases is largely dependent on the differentiation of oligodendrocytes precursor cells (OPCs) into mature myelin-forming OLGs at the demyelinated lesions, which is defined as remyelination. We discover that baicalin (BA), a natural flavonoid, in addition to its well-known antiinflammatory effects, directly stimulates OLG maturation and CNS myelin repair. METHODS: To investigate the function of BA on CNS remyelination, we develop the complementary in vivo and in vitro models, including physiologic neonatal mouse CNS myelinogenesis model, pathologic cuprizone-induced (CPZ-induced) toxic demyelination model, and postnatal OLG maturation assay. Furthermore, molecular docking, pharmacologic regulation, and transgenic heterozygous mice were used to clarify the target and action of the mechanism of BA on myelin repair promotion. RESULTS: Administration of BA was not only merely effectively enhanced CNS myelinogenesis during postnatal development but also promoted remyelination and reversed the coordination movement disorder in the CPZ-induced toxic demyelination model. Of note, myelin-promoting effects of BA on myelination or regeneration is peroxisome proliferator-activated receptor γ (PPARγ) signaling-dependent. DISCUSSION: Our work demonstrated that BA promotes myelin production and regeneration by activating the PPARγ signal pathway and also confirmed that BA is an effective natural product for the treatment of demyelinating diseases.

A Disaster Response and Management Competency Mapping of Community Nurses in China.

BACKGROUND: It is widely accepted in many parts of the world thatcommunity nurses are of vital importance in various phases of disaster response and management. In China, however, it is not clear whether the Chinese community nurses are able to assume disaster-related duties due to the lack of a systematic assessment. METHODS: A pre-designed and well-tested questionnaire was employed to evaluate the competency in disaster response and management among 205 valid registered Chinese community nurses between September and October 2009. Statistical analyses were performed with SPSS Version 13.0 using one way ANOVA, Least Significant Difference (LSD) and multiple stepwise regression analysis. RESULTS: This group of Chinese community nurses scored at an intermediate level of competency (a score of 3.68 (SD 0.48) out of a perfect score of 5) in disaster response and management, suggesting that they have the basic ability to participate in disaster-related nursing. Four factors, namely, Experiences in Disaster Relief, Participation in Disaster Training, the Age and Duration in Job, were identified to be the predominant factors contributing significantly to the integrated competency in disaster response and management of an individual. CONCLUSION: Most of the Chinese community nurses have basic qualifications and competencies to undertake the responsibilities of disaster response and management. However, more targeted disaster training including virtual-reality based drills should be provided in order to improve their competency.