Anti-inflammatory effects of 6S-5-methyltetrahydrofolate-calcium on RAW264.7 cells and zebrafish.

AIM: 6S-5-methyltetrahydrofolate is the predominant form of dietary folate in circulation and is used as a crystalline form of calcium salt (MTHF-Ca). Reports revealed that MTHF-Ca was more safe than folic acid, a synthetic and highly stable version of folate. Folic acid has been reported to have anti-inflammatory effects. The study's objective was to assess the anti-inflammatory effect of MTHF-Ca in vitro and in vivo. MAIN METHODS: In vitro, the ROS production was assessed by H2DCFDA, and nuclear translocation of NF-κB were evaluated by the NF-κB nuclear translocation assay kit. Interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α) were assessed using ELISA. In vivo, ROS production was assessed by H2DCFDA, neutrophils and macrophages recruitment were evaluated in tail transection-induced and CuSO4-induced zebrafish inflammation models. Expression of inflammation related genes were also investigated based on CuSO4-induced zebrafish inflammation model. KEY FINDINGS: MTHF-Ca treatment decreased LPS-induced ROS production, inhibited nuclear translocation of NF-κB and decreased the levels of IL-6, IL-1ß and TNF-α in RAW264.7 cells. In addition, MTHF-Ca treatment inhibited ROS production, suppressed the recruitment of neutrophils and macrophages, and reduced the expression of inflammation related genes, including jnk, erk, nf-κb, myd88, p65, tnf-α, and il-1b in zebrafish larvae. SIGNIFICANCE: MTHF-Ca may play an anti-inflammatory role by reducing the recruitment of neutrophils and macrophages and keeping the low levels of proinflammatory mediators and cytokines. MTHF-Ca may have a potential role in the treatment of inflammatory diseases.

Evaluation of Cardiovascular Toxicity of Folic Acid and 6S-5-Methyltetrahydrofolate-Calcium in Early Embryonic Development.

Folic acid (FA) is a synthetic and highly stable version of folate, while 6S-5-methyltetrahydrofolate is the predominant form of dietary folate in circulation and is used as a crystalline form of calcium salt (MTHF-Ca). The current study aims to evaluate the toxicity and safety of FA and MTHF-Ca on embryonic development, with a focus on cardiovascular defects. We began to analyze the toxicity of FA and MTHF-Ca in zebrafish from four to seventy-two hours postfertilization and assessed the efficacy of FA and MTHF-Ca in a zebrafish angiogenesis model. We then analyzed the differently expressed genes in in vitro fertilized murine blastocysts cultured with FA and MTHF-Ca. By using gene-expression profiling, we identified a novel gene in mice that encodes an essential eukaryotic translation initiation factor (Eif1ad7). We further applied the morpholino-mediated gene-knockdown approach to explore whether the FA inhibition of this gene (eif1axb in zebrafish) caused cardiac development disorders, which we confirmed with qRT-PCR. We found that FA, but not MTHF-Ca, could inhibit angiogenesis in zebrafish and result in abnormal cardiovascular development, leading to embryonic death owing to the downregulation of eif1axb. MTHF-Ca, however, had no such cardiotoxicity, unlike FA. The current study thereby provides experimental evidence that FA, rather than MTHF-Ca, has cardiovascular toxicity in early embryonic development and suggests that excessive supplementation of FA in perinatal women may be related to the potential risk of cardiovascular disorders, such as congenital heart disease.

Construction of hollow core-shelled nitrogen-doped carbon-coated yttrium aluminum garnet composites toward efficient microwave absorption.

High-performance microwave absorbing materials (MAMs) play a vital role in electromagnetic (EM) pollution protection. Multi-interfacial heterogeneous structure design has become a mainstream direction for designing and fabricating excellent MAMs. Herein, multi-interfacial hollow core-shelled yttrium aluminum garnet@nitrogen-doped carbon (YAG@NC) composites were synthesized by coprecipitation, thermal treatment, self-polymerization and carbonization processes. Thermal treatment temperatures were used to regulate the defect level and interfaces in carbon materials. Defects of NC and multiple interfaces favor dielectric polarization, and the hollow cavity endows the MAMs with lightweight characteristics and ideal impedance matching. The results indicated that YAG@NC composites possess excellent microwave absorption properties with an effective absorption bandwidth (EAB) of 5.5 GHz at an absorber thickness of only 1.95 mm. The radar cross section (RCS) reduction of YAG@NC composites was verified by CST simulation in the far field, and the strongest RCS reduction value was up to 32.64 dBm2 with a scattering angle of 0°. This work paves the way for designing multicomponent microstructure dielectric loss absorbers with broadband and strong microwave absorption.

Self-Assembled Peptide Functionalized Gold Nanopolyhedrons with Excellent Chiral Optical Properties.

Because of the unique optical properties of gold nanomaterials, the preparation of gold nanomaterials with excellent chirality has received extensive attention. In order to develop a simple fabrication method for three-dimensional chiral Au nanostructures with a size of several hundred nanometers, chiral gold nanoparticles were developed to transfer chirality of a peptide to gold nanoparticles. In this study, the controlled synthesis of asymmetric gold nanopolyhedrons was achieved. The asymmetric gold nanopolyhedrons prepared via peptide-directed growth can exhibit strong circular dichroism (∼±50 mdeg) couplets in the visible range (500-600 nm). Also, the morphology of chiral Au nanododecahedrons-peptide particles showed distorted and asymmetric properties. In order to prove that the size and spatial structure of gold nanopolyhedrons have an influence on their chiral optical properties, Au nanotrioctahedron-peptide particles were prepared by using Au nanotrioctahedrons with different morphologies. Au nanotrioctahedron-peptide particles also exhibited circular dichromatic couplets in the visible region.