RNA interference-mediated silencing of DNA methyltransferase 1 attenuates neuropathic pain by accelerating microglia M2 polarization.

BACKGROUND: DNA methyltransferase 1 (DNMT1) exerts imperative functions in neuropathic pain (NP). This study explored the action of RNA interference-mediated DNMT1 silencing in NP by regulating microglial M2 polarization. METHODS: NP rat models were established using chronic constriction injury (CCI) and highly aggressive proliferating immortalized (HAPI) microglia were treated with lipopolysaccharide (LPS) to induce microglia M1 polarization, followed by treatment of DNMT1 siRNA or si-DNMT1/oe-DNMT1, respectively. The pain threshold of CCI rats was assessed by determining mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL). Levels of inflammatory factors (TNF-α/IL-1ß/IL-6/IL-10) and DNMT1 in rat L4-L6 spinal cord samples and HAPI cells were measured using ELISA, RT-qPCR, and Western blot. iNOS and Arg-1 mRNA levels were measured via RT-qPCR. DNMT1, M1 marker (iNOS), and M2 marker (Arg-1) levels in microglia of CCI rats were detected by immunofluorescence. Percentages of M1 microglia phenotype (CD16) and M2 microglia phenotype (CD206) were detected by flow cytometry. The phosphorylation of PI3K/Akt pathway-related proteins was determined by Western blot. RESULTS: CCI rats exhibited diminished MWT and TWL values, increased pro-inflammatory cytokines, and decreased anti-inflammatory cytokine IL-10. Additionally, DNMT1 was upregulated in CCI rat microglia. DNMT1 siRNA alleviated CCI-induced NP and facilitated M2 polarization of microglia in CCI rats. DNMT1 knockdown inhibited LPS-induced M1 polarization of HAPI cells and promoted M2 polarization by blocking the PI3K/Akt pathway, but DNMT1 overexpression inhibited the M1-to-M2 polarization of microglia. CONCLUSION: RNA interference-mediated DNMT1 silencing accelerates microglia M2 polarization by impeding the PI3K/Akt pathway, thereby alleviating CCI-induced NP.

Light response of gametophyte in Adiantum flabellulatum: transcriptome analysis and identification of key genes and pathways.

Light serves not only as a signaling cue perceived by plant photoreceptors but also as an essential energy source captured by chloroplasts. However, excessive light can impose stress on plants. Fern gametophytes possess the unique ability to survive independently and play a critical role in the alternation of generations. Due to their predominantly shaded distribution under canopies, light availability becomes a limiting factor for gametophyte survival, making it imperative to investigate their response to light. Previous research on fern gametophytes' light response has been limited to the physiological level. In this study, we examined the light response of Adiantum flabellulatum gametophytes under different photosynthetic photon flux density (PPFD) levels and identified their high sensitivity to low light. We thereby determined optimal and stress-inducing light conditions. By employing transcriptome sequencing, weighted gene co-expression network analysis, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, we identified 10,995 differentially expressed genes (DEGs). Notably, 3 PHYBs and 5 Type 1 CRYs (CRY1s) were significantly down-regulated at low PPFD (0.1 µmol m-2 s-1). Furthermore, we annotated 927 DEGs to pathways related to photosynthesis and 210 to the flavonoid biosynthesis pathway involved in photoprotection. Additionally, we predicted 34 transcription factor families and identified a close correlation between mTERFs and photosynthesis, as well as a strong co-expression relationship between MYBs and bHLHs and genes encoding flavonoid synthesis enzymes. This comprehensive analysis enhances our understanding of the light response of fern gametophytes and provides novel insights into the mechanisms governing their responses to light.

Proteome profile of glycrol-mediated salt-reduction cured meat reveals the formation mechanism of eating quality.

Although it has been ignored for some time, mediated curing has an impact on the quality of dry-cured meat products, and the understanding of such impact can be beneficial to the development of low-sodium cured meat products. In this paper, the effect of glycerol (a curing mediator) on the quality of cured meat was investigated. The results revealed that the curing mediated by glycerol could reduce the contents of salt and water and the hardness of cured meat (P < 0.05). Further, the influence of glycerol-mediated curing on muscle protein was evaluated by tandem mass tag quantitative proteomics, and the proteome profiles of tenderloin in the glycerol-mediated curing and control groups were compared. The results showed that the upregulated differentially expressed proteins (DAPs) in glycerol-mediated cured tenderloin were mainly involved in oxidative phosphorylation and thermogenesis pathways from the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. In addition, the downregulated DAPs were mainly involved in the regulation of actin cytoskeleton. These DAPs and the participated pathways were related to meat characteristics. Based on the results, it is convincing that glycerol-mediated curing is an effective method for producing low-sodium cured meat products.

Full-length transcriptome analysis of Adiantum flabellulatum gametophyte.

Ferns are important components of plant communities on earth, but their genomes are generally very large, with many redundant genes, making whole genome sequencing of ferns prohibitively expensive and time-consuming. This means there is a significant lack of fern reference genomes, making molecular biology research difficult. The gametophytes of ferns can survive independently, are responsible for sexual reproduction and the feeding of young sporophytes, and play an important role in the alternation of generations. For this study, we selected Adiantum flabellulatum as it has both ornamental and medicinal value and is also an indicator plant of acidic soil. The full-length transcriptome sequencing of its gametophytes was carried out using PacBio three-generation sequencing technology. A total of 354,228 transcripts were obtained, and 231,705 coding sequences (CDSs) were predicted, including 5,749 transcription factors (TFs), 2,214 transcription regulators (TRs) and 4,950 protein kinases (PKs). The transcripts annotated by non-redundant protein sequence database (NR), Kyoto encyclopedia of genes and genomes (KEGG), eukaryotic ortholog groups (KOG), Swissprot, protein family (Pfma), nucleotide sequence database (NT) and gene ontology (GO) were 251,501, 197,474, 193,630, 194,639, 195,956, 113,069 and 197,883, respectively. In addition, 138,995 simple sequence repeats (SSRs) and 111,793 long non-coding RNAs (lncRNAs) were obtained. We selected nine chlorophyll synthase genes for qRT-PCR, and the results showed that the full-length transcript sequences and the annotation information were reliable. This study can provide a reference gene set for subsequent gene expression quantification.

Excavation of Genes Responsive to Brassinosteroids by Transcriptome Sequencing in Adiantum flabellulatum Gametophytes.

Brassinosteroids (BRs) are a class of polyhydroxysteroid plant hormones; they play important roles in the development and stress resistance of plants. The research on BRs has mainly been carried out in angiosperms, but in ferns-research is still limited to the physiological level and is not in-depth. In this study, Adiantum flabellulatum gametophytes were used as materials and treated with 10-6 M brassinolide (BL). The differentially expressed genes (DEGs) responsive to BRs were identified by transcriptome sequencing, GO, KEGG analysis, as well as a quantitative real-time polymerase chain reaction. From this, a total of 8394 DEGs were screened. We found that the expressions of photosynthetic genes were widely inhibited by high concentrations of BL in A. flabellulatum gametophytes. Moreover, we detected many BR synthase genes, except BR6ox2, which may be why castasterone (CS) rather than BL was detected in ferns. Additionally, we identified (for the first time) that the expressions of BR synthase genes (CYP90B1, CYP90C1, CYP90D1, CPD, and BR6ox1) were negatively regulated by BL in fern gametophytes, which indicated that ferns, including gametophytes, also needed the regulatory mechanism for maintaining BR homeostasis. Based on transcriptome sequencing, this study can provide a large number of gene expression data for BRs regulating the development of fern gametophytes.

Effects of Dietary 5'-CMP on Neu5Gc Contents in the Muscle and Viscera of Xiang Pigs.

ABSTRACT: In order to reduce the health risks associated with red meat as listed by the World Health Organization, the work presented in this article aimed to elucidate the interaction between 5'-CMP-supplemented feed and N-glycolylneuraminic acid (Neu5Gc) in experimental animals in vivo. 5'-CMP was added to the diet of 90-, 180-, and 270-day-old Xiang pigs, and after 30 days, the Neu5Gc contents, physicochemical parameters, and free amino acid contents of muscle and internal viscera were measured by high-performance liquid chromatography coupled with fluorescence detection. The mechanism by which 5'-CMP affects Neu5Gc contents was investigated using molecular docking. Results show that 5'-CMP significantly decreased the Neu5Gc content in 180-day-old Xiang pigs (P < 0.05) but had no effect on the Neu5Gc contents in 90- and 270-day-old Xiang pigs. Umami amino acids were significantly increased in 180-day-old Xiang pigs. In the 90- and 270-day-old pigs, histidine increased by 10.38 and 17.87%, respectively. The other free amino acids were either reduced or not affected. Moreover, the 5'-CMP-supplemented diet did not affect the physicochemical parameters of the longissimus muscle in the Xiang pigs. 5'-CMP could occupy almost all the sialyltransferase active-site residues but not His302 and showed inhibition of the sialyltransferase activity. The results provided an experimental basis for the subsequent reduction of Neu5Gc in red meat before slaughter.

[Clinical observation of percutaneous coblation nucleoplasty for the treatment of cervical spondylotic radiculopathy].

OBJECTIVE: To evaluate the clinical effects of percutaneous coblation nucleoplasty in treating cervical spondylotic radiculopathy and investigate its mechanism of action. METHODS: Form January 2015 to January 2017, 21 patients with cervical spondylotic radiculopathy were treated by percutaneous coblation nucleoplasty, including 8 males and 13 females with an average age of 49.6 years old ranging from 43 to 61 years old. The course of disease was for 1 to 6 months with a median age of 4 months. Three cases were single segment, 9 cases were double segments, 7 cases were three-segment, 2 cases were four-segment. Intervertebral disc pressure, VAS were compared before and after operation. Angular displacement(AD) and horizontal displacement(HD) were measured by image data and in order to evaluate the cervical stability. Modified MacNab criteria was used to assess clinical effects. RESULTS: All the patients were followed up from 1 to 12 months with an average of 8.6 months. Preoperative intervertebral disc pressure was (32.0±5.26) cmH2O and immediately after operation was (21.0±7.18) cmH2O, there was statistical significance between before and after operation(P=0.003). Preoperative angular displacement and horizontal displacement was (3.85±1.26) ° and (1.23±0.58) mm, six months after operation was (4.18±1.31) ° and (1.69±0.46) mm, respectively. There was no statistical significance before and after operation(P>0.05). Preoperative VAS scores were 7.49±0.53, postoperative at 3 days, 3, 6 months were 3.51±0.49, 2.63±0.61, 2.56±0.71, respectively, and postoperative obtained obvious improvement(P<0.05). According to modified MacNab criteria, 6 cases obtained excellent results, 7 good, 4 fair 3 poor at 3 days;10 cases obtained excellent results, 5 good, 3 fair, 2 poor at 3 months; 12 cases obtained excellent results, 6 good, 1 fair, 1 poor at 6 months after operation. Postoperative clinical effect at 6 months was better than 3 d, and 3 months(P<0.05), and postoperative at 3 months was better than 3 d(P<0.05). CONCLUSIONS: Percutaneous coblation nucleoplasty in treating cervical spondylotic radiculopathy can effectively relieve the pain of neck, shoulder and upper limb and can also relieve some associated symptoms such as headache and dizziness.

The remanence ratio in CoFe2O4 nanoparticles with approximate single-domain sizes.

Approximately single-domain-sized 9-, 13-, and 16-nm CoFe2O4 nanoparticles are synthesized using the thermal decomposition of a metal-organic salt. By means of dilution and reduction, the concentration, moment, and anisotropy of nanoparticles are changed and their influence on the magnetic properties is investigated. The relation of M r/M s ∝ 1/lgH dip is observed, where M r/M s is the remanence ratio and H dip is the maximum dipolar field. Especially, such relation is more accurate for the nanoparticle systems with higher concentration and higher moment, i.e., larger H dip. The deviation from M r/M s ∝ 1/lgH dip appearing at low temperatures can be attributed to the effects of surface spins for the single-phase CoFe2O4 nanoparticles and to the pinning effect of CoFe2O4 on CoFe2 for the slightly reduced nanoparticles. Graphical Abstract Approximately single-domain-sized 9-, 13-, and 16-nm CoFe2O4 nanoparticles were synthesized and then the concentration, moment, and anisotropy of these NPs were changed. The correlation of M r/M s ∝ 1/lgH dip was observed, independent of the size, concentration, moment, and anisotropy, and especially, such correlation is more accurate for the nanoparticle systems with higher concentration or moment, i.e., stronger dipolar interaction, which has not been reported before as far as we know.

The effects of surface spin on magnetic properties of weak magnetic ZnLa0.02Fe1.98O4 nanoparticles.

In order to prominently investigate the effects of the surface spin on the magnetic properties, the weak magnetic ZnLa0.02Fe1.98O4 nanoparticles were chosen as studying objects which benefit to reduce as possibly the effects of interparticle dipolar interaction and crystalline anisotropy energies. By annealing the undiluted and diluted ZnLa0.02Fe1.98O4 nanoparticles at different temperatures, we observed the rich variations of magnetic ordering states (superparamagnetism, weak ferromagnetism, and paramagnetism). The magnetic properties can be well understood by considering the effects of the surface spin of the magnetic nanoparticles. Our results indicate that in the nano-sized magnets with weak magnetism, the surface spin plays a crucial rule in the magnetic properties.

Microporous metal-organic framework constructed from heptanuclear zinc carboxylate secondary building units.

A novel, three-dimensional, noninterpenetrating microporous metal-organic framework (MOF), [Zn7O2(pda)5(H2O)2]5 DMF4 EtOH 6 H2O (1) (H2PDA=p-phenylenediacrylic acid, DMF=N,N-dimethylformamide, EtOH=ethanol), was synthesized by constructing heptanuclear zinc carboxylate secondary building units (SBUs) and by using rigid and linear aromatic carboxylate ligands, PDA. The X-ray crystallographic data reveals that the seven zinc centers of 1 are held together with ten carboxylate groups of the PDA ligands and four water molecules to form a heptametallic SBU, Zn7O4(CO2)10, with dimensions of 9.8 x 9.8 x 13.8 A3. Furthermore, the heptametallic SBUs are interconnected by PDA acting as linkers, thereby generating an extended network with a three-dimensional, noninterpenetrating, intersecting large-channel system with spacing of about 17.3 A. As a microporous framework, polymer 1 shows adsorption behavior that is favorable towards H2O and CH3OH, and substantial H2 uptake. In terms of the heptanuclear zinc carboxylate SBUs, polymer 1 exhibits interesting photoelectronic properties, which would facilitate the exploration of new types of semiconducting materials, especially among MOFs containing multinuclear metal carboxylate SBUs.