The assembly of gut microbiota implicates shrimp acute hepatopancreas necrosis disease progression.

Ample evidence shows dysbiosis in the gut microbiota when comparing healthy shrimp with those affected by severe acute hepatopancreatic necrosis disease (AHPND). However, the static comparison used in available studies leads to the uncertainties regarding how and to what extent the gut microbiota responds to the progressive severity of AHPND. In addition, shrimp AHPND is featured by rapid and massive mortality, thus the initiation of AHPND must be diagnosed for preemptive therapy. For these reasons, we explored the ecological assembly of gut microbiota over shrimp AHPND progression. Increasing AHPND severity was associated with linear increase in the copies of pirAB genes, relative abundance of gut Vibrio and potentially pathogenic, and reduction in the gut bacterial diversity, stability, and relative abundance of Bdellovibrio. Negative and significant association between gut Vibrio and Bdellovibrio were noted, indicating that compromised predation exerts a role in AHPND progression. Notably, the extents of departure to the healthy shrimp gut microbiota were positively coupled with the increasing severity of AHPND. After controlling the temporal variation in the gut microbiota as healthy shrimp age, we constructed a diagnosis model that accurately diagnosed the initial, progressed or moribund stages of AHPND, with an overall accuracy of 86.5%. Shrimp AHPND induced more stochastic gut microbiotas as a consequence of the attenuated ability of diseased shrimp to select their commensals, resulting in convergent bacterial communities between gut and rearing water over AHPND progression. Collectively, our findings provide important step toward the ecological assembly of gut microbiota implicating in AHPND etiology and in diagnosing AHPND stages. KEY POINTS: • The departure of shrimp gut microbiota positively linked with AHPND severity. • The diagnosis model accurately diagnosed the stages of AHPND. • Shrimp AHPND induced more stochastic gut microbiota.

Nanoemulsion enhances α-tocopherol succinate bioavailability in rats.

The vitamin E analogue, α-tocopherol succinate (α-TOS), has a broad anti-tumor effect. α-TOS can induce cancer cells apoptosis and suppress tumor growth by targeting mitochondria. Low bioavailability of α-TOS is the major problem encountered with formulation development. In our study, α-TOS nanoemulsion (α-TOS-NE) was demonstrated as a new drug delivery system of α-TOS to increase the bioavailability. MTT-based cytotoxicity assay and mitochondrial membrane potential (ΔY) were performed on human breast cancer cell lines MCF-7 and human oral epithelial cancer cell lines KB to evaluate in vitro anticancer efficacy of α-TOS-NE. In comparison with free α-TOS, α-TOS-NE exhibited a stronger cytotoxicity and decreased ΔΨ. Pharmacokinetic profiles of I.V. α-TOS-NE group, I.P. α-TOS-NE group, and I.P. free α-TOS group (7% DMSO/93% PEG) were drawn. First of all, nanoemultion (NE) enables the I.V. injection of α-TOS, make it possible to be an I.V. preparation. Second, compare to the I.P. free α-TOS group, I.P. α-TOS-NE group had a higher bioavailability. Thus, NE improved the strong anti-cancer efficacy of α-TOS while increasing its in vivo bioavailability in rats. In conclusion, our laboratory-made NE was a safe drug delivery system for clinical trials and could be a promising formulation for α-TOS by I.V administration.

Vitamin E derivative-based multifunctional nanoemulsions for overcoming multidrug resistance in cancer.

The multidrug resistance (MDR), including intrinsic and acquired multidrug resistance, is a major problem in tumor chemotherapy. Here, we proposed a strategy for modulating intrinsic and/or acquired multidrug resistance by altering the levels of Bax and Bcl-2 expression and inhibiting the transport function of P-gp, increasing the intracellular concentration of its substrate anticancer drugs. Vitamin E derivative-based nanoemulsions containing paclitaxel (MNEs-PTX) were fabricated in this study, and in vitro anticancer efficacy of the nanoemulsion system was evaluated in the paclitaxel-resistant human ovarian carcinoma cell line A2780/Taxol. The MNEs-PTX exhibited a remarkably enhanced antiproliferation effect on A2780/Taxol cells than free paclitaxel (PTX) (p < 0.01). Compared with that in the Taxol group, MNEs-PTX further decreased mitochondrial potential. Vitamin E derivative-based multifunctional nanoemulsion (MNEs) obviously increased intracellular accumulation of rhodamine 123 (P-gp substrate). Overexpression of Bcl-2 is generally associated with tumor drug resistance, we found that MNEs could reduce Bcl-2 protein level and increase Bax protein level. Taken together, our findings suggest that anticancer drugs associated with MNEs could play a role in the development of MDR in cancers.