In situ bio-mineralized Mn nanoadjuvant enhances anti-influenza immunity of recombinant virus-like particle vaccines.

Virus like particles (VLPs) have been well recognized as one of the most important vaccine platforms due to their structural similarity to natural viruses to induce effective humoral and cellular immune responses. Nevertheless, lack of viral nucleic acids in VLPs usually leads the vaccine candidates less efficient in provoking innate immune against viral infection. Here, we constructed a biomimetic dual antigen hybrid influenza nanovaccines THM-HA@Mn with robust immunogenicity via in situ synthesizing a stimulator of interferon genes (STING) agonist Mn3O4 inside the cavity of a recombinant Hepatitis B core antigen VLP (HBc VLP) having fused SpyTag and influenza M2e antigen peptides (Tag-HBc-M2e, THM for short), followed by conjugating a recombinant hemagglutinin (rHA) antigen on the surface of the nanoparticles through SpyTag/SpyCatcher ligating. Such inside Mn3O4 immunostimulator-outside rHA antigen design, together with the chimeric M2e antigen on the HBc skeleton, enabled the synthesized hybrid nanovaccines THM-HA@Mn to well imitate the spatial distribution of M2e/HA antigens and immunostimulant in natural influenza virus. In vitro cellular experiments indicated that compared with the THM-HA antigen without Mn3O4 and a mixture vaccine consisting of THM-HA + MnOx, the THM-HA@Mn hybrid nanovaccines showed the highest efficacies in dendritic cells uptake and in promoting BMDC maturation, as well as inducing expression of TNF-α and type I interferon IFN-ß. The THM-HA@Mn also displayed the most sustained antigen release at the injection site, the highest efficacies in promoting the DC maturation in lymph nodes and germinal center B cells activation in the spleen of the immunized mice. The co-delivery of immunostimulant and antigens enabled the THM-HA@Mn nanovaccines to induce the highest systemic antigen-specific antibody responses and cellular immunogenicity in mice. Together with the excellent colloid dispersion stability, low cytotoxicity, as well as good biosafety, the synthetic hybrid nanovaccines presented in this study offers a promising strategy to design VLP-based vaccine with robust natural and adaptive immunogenicity against emerging viral pathogens.

Simultaneous determination of six coptis alkaloids in urine and feces by LC-MS/MS and its application to excretion kinetics and the compatibility mechanism of Jiao-Tai-Wan in insomniac rats.

Jiao-Tai-Wan (JTW) is a well-known traditional Chinese medicine prescription composed of Rhizoma Coptidis (RC) and Cortex Cinnamon (10:1, g/g). It has been used to treat insomnia in China for centuries. This study investigates the excretion properties of coptis alkaloids from RC and JTW in normal and insomniac rats, and it examines the compatibility mechanism for this prescription. A new liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of six alkaloids - berberine, epiberberine, coptisine, jatrorrhizine, palmatine and magnoflorine - in rat urine and feces. The normal and model rats were orally treated with RC and JTW powder at a dosage containing 3.0 g kg-1  day-1 RC once per day for 7 days. Briefly, the results showed that the cumulative amounts of urinary and fecal excretion of the six alkaloids were significantly different in the pathological condition, as well as in compatibility. In normal rats, the urinary and fecal excretion of coptis alkaloids, especially berberine, coptisine and palmatine, increased significantly in the JTW group compared with the RC group, while the urinary and fecal excretion of six alkaloids decreased in insomniac rats. These data suggested that pathological conditions might have a notable influence on the excretion of alkaloids in rats, and demonstrated that the compatibility could promote better therapeutic effects through the accumulation of alkaloids in the body. These results might explain the compatibility of JTW.

[Study on mechanism of hepatotoxicity of Ploygoni Multiflori Caulis based on function inhibition of bilirubin-associated transporters in idiosyncratic rat].

To explore the possible mechanism of liver injury, the effects of Ploygoni Multiflori Caulis and its extractive on the function of bilirubin-associated transporters were investigated in normal (N) and idiosyncratic (LPS) rats (M). The normal and LPS rats were respectively administrated powder of Ploygoni Multiflori Caulis, its extractive and same volume of 0.5% CMC-Na solution for 7 d. BSP, a substrate of the transporters of Oatp1a1 and Oatp1b2 was selected, and its pharmacokinetic parameters of intravenous injection were determined to examined the activity these transporters. Meanwhile the mRNA expressions of transporters were detected. Compared with N-blank control group, besides M-powder group, the Cmax has no significantly different from other groups, t1/2, AUC0-t and AUC0-∞ were significantly increased, and CL were significantly decreased. However, compared with N- blank control group, AST and ALT decreased significantly. The expression of Oatp1a1, Oatp1b2 and MRP2 mRNA was significantly decreased (P<0.05), but there was no act synergistically when Ploygoni Multiflori Caulis and extractive were combined with LPS. The function of Oatp1a1, Oatp1b2 and MRP2 in rats were significantly inhibited by Ploygoni Multiflori Caulis and extractive, which may be an important cause of hepatotoxicity.

[In vitro effects of Genkwa Flos chloroform extract on activity of human liver microsomes UGTs and UGT1A1].

To predict the mechanism of liver injury induced by Genkwa Flos, we investigated the effect of chloroform extract on UGTs and UGT1A1 activities of the liver microsomes in rat and human. In the present study, 4-nitrophenol(4-NP) and ß-estradiol were elected as substrates to determine activities of UGTs and UGT1A1 by UV and HPLC. The results showed that there were 1.00% of apigenin, 6.40% of hydroxygenkwanin and 18.38% of genkwanin in chloroform extract; and total diterpene mass fraction was 31.40%. Compared with the control group, chloroform extract could significantly inhibit the activity of UGTs in rat liver microsomes(RLM) system, while the inhibitory effect was not obvious in human liver microsomes(HLM) system. UGT1A1 activity was inhibited by chloroform extract in rat liver microsomes and human liver microsomes (based on genkwanin, IC50=8.76, 10.36 µmol•L⁻¹). The inhibition types were non-competitive inhibition(RLM) and uncompetitive inhibition(HLM). In conclusion, the results indicated that chloroform extract showed different inhibitory effects on UGTs and UGT1A1 activity, which may be one of the mechanisms of liver injury induced by Genkwa Flos.