Staphylococcus aureus is a zoonotic opportunistic pathogen that represents a significant threat to public health. Previous studies have shown that tannic acid (TA) has an inhibitory effect on a variety of bacteria. In this study, the proteome and transcriptome of S. aureus were analyzed to comprehensively assess changes in genes and proteins induced by TA. Initial observations of morphological changes revealed that TA damaged the integrity of the cell membrane. Next, proteomic and genetic analyses showed that exposure to TA altered the expression levels of 651 differentially expressed proteins (DEPs, 283 upregulated and 368 downregulated) and 503 differentially expressed genes (DEGs, 191 upregulated and 312 downregulated). Analysis of the identified DEPs and DEGs suggested that TA damages the integrity of the cell envelope by decreasing the expression and protein abundance of enzymes involved in the synthesis of peptidoglycans, teichoic acids and fatty acids, such as murB, murQ, murG, fmhX and tagA. After treatment with TA, the assembly of ribosomes in S. aureus was severely impaired by significant reductions in available ribosome components, and thus protein synthesis was hindered. The levels of genes and proteins associated with amino acids and purine synthesis were remarkably decreased, which further reduced bacterial viability. In addition, ABC transporters, which are involved in amino acid and ion transport, were also badly affected. Our results reveal the molecular mechanisms underlying the effects of TA on S. aureus and provide a theoretical basis for the application of TA as an antibacterial chemotherapeutic agent.
Innate and adaptive immunity are intricately linked to the pathogenesis of ulcerative colitis (UC), with dysregulation of the Treg/Th17 balance and M2/M1 macrophage polarization identified as critical factors. Artesunate (ARS) has previously been shown to alleviate UC by inhibiting endoplasmic reticulum stress (ERS). To further investigate the regulatory effects of ARS on immune dysregulation associated with colitis and the role of ERS in this process, an experimental colitis model was established using dextran sulfate sodium (DSS). Flow cytometry was employed to assess changes in the Th17/Treg cell ratio in the spleen and macrophage polarization in the intestine, while RT-qPCR was used to quantify the transcription levels of relevant genes in colonic tissues. ARS treatment significantly mitigated DSS-induced pathological damage, reduced the proportion of CD4+Th17 cells, and downregulated the mRNA expression of IL-17A, IL-17F, and RORγt, while concurrently increasing the proportion of CD4+Treg cells and upregulating TGF-β expression. Additionally, ARS restored the DSS-induced decline in the M2/M1 macrophage ratio and enhanced the transcription of Arg-1 and IL-10, while suppressing the expression of pro-inflammatory markers, including iNOS, IL-1β, IL-6, and TNF-α. Notably, co-treatment with 4-phenylbutyric acid (4-PBA, ERS inhibitor) augmented the immunoregulatory effects of ARS, whereas 2-deoxy-D-glucose (2-DG, ERS agonist) co-treatment counteracted its protective activity against UC. These findings suggest that ERS plays a crucial role in mediating the therapeutic effects of ARS on UC, particularly by modulating Th17/Treg balance and macrophage polarization. This study provides further insights into the mechanistic basis of ARS in UC treatment offering a potential avenue for therapeutic intervention.
This study aimed to develop nanostructured lipid carriers (NLCs) for improved oral absorption of tilmicosin (TMS) in broilers. Thus, palmitic acid, lauric acid, and stearic acid were selected as solid lipids to formulate TMS-pNLCs, TMS-lNLCs, and TMS-sNLCs, respectively. They showed similar physicochemical properties and meanwhile possessed excellent storage and gastrointestinal stability. The TMS interacted with the lipid matrix and was encapsulated efficiently in NLCs in an amorphous structure. NLCs could enhance oral absorption of TMS compared to 10% tilmicosin phosphate solution in broilers, among which the TMS-sNLCs were the most efficient drug delivery carriers, with a relative oral bioavailability of 203.55%. NLCs could inhibit the efflux of P-glycoprotein (P-pg) toward TMS, which may be involved with improved oral absorption. Taken together, these types of solid lipids influenced the enhanced level of NLCs toward oral bioavailability of TMS, and the sNLCs proved to be the most promising oral delivery carriers of TMS.
1 June 2020 in Biological and Pharmaceutical Bulletin
Rotavirus (RV) induced diarrhea has been a major reason affecting children healthy under 5 years old especially in developing countries. Although specific vaccines have preventive effects, antiviral therapy is essential for the diarrhea patients. Ziyuglycoside II is a traditional Chinese herb which has been proven to possess anti-virus effects. This study aimed to investigate the roles of Ziyuglycoside II in rotavirus-induced diarrhea and the underlying molecular mechanism. We found that normal MA104 cells treated with RV became swollen and gather together. However, Ziyuglycoside II treatment inhibited cell growth in a dose- and time dependent manner and suppressed RV replication. Moreover, Ziyuglycoside II reversed RV-induced downregulation of anti-inflammatory cytokine interleukin (IL)-10 and upregulation of pro-inflammatory factors, such as interferon-gamma (IFN-gamma), IL-1 beta, IL-6, and tumor necrosis factor (TNF-alpha). Moreover, Ziyuglycoside II administration and ribavirin blocked toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-kappa B) signaling pathway both in mRNA and protein level, which was paralleled with immunohistochemical assay. Additionally, Ziyuglycoside II administration improved diarrhea symptoms and decreased diarrhea scores. Ziyuglycoside II and ribavirin inhibited the apoptosis of small intestine epithelial cells induced by RV. Taken together, RV treatment induced diarrhea. Ziyuglycoside II administration inhibited TLR4/NF-kappa B pathway and inflammatory response and improved RV-induced diarrhea. The inhibitory effects of Ziyuglycoside II on RV-induced diarrhea predicted Ziyuglycoside II may be a promising drug for diarrhea.
1 June 2022 in International Journal of Nanomedicine
Introduction: Cefquinome sulfate (CS) is the first fourth-generation antibiotic for animals, which has a wide antibacterial spectrum, strong antibacterial activity and low drug resistance. However, it is accompanied by problems of poor therapeutic efficacy. In this context, the use of nanosuspensions have been found to be an attractive strategy. The main objective of this work is to develop a new oily nanosuspension to improve bioavailability and stability of CS formulations. Methods: After screening the formulations, cefquinome sulfate oily nanosuspension (CS-NSP) was prepared by mortar grinding, using propylene glycol dicaprolate/dicaprate (Labrafac™ PG) as oil medium and caprylocaproyl polyoxyl-8 glycerides (Labrasol®) as stabilizer. The properties of CS-NSP were investigated by testing its physicochemical characteristics, stability, in vitro release, hemolysis, and muscle irritation. The in vivo pharmacokinetics of CS-NSP was studied using rats. Results: Results show that CS-NSP presents suitable stability, physicochemical properties and safety. Moreover, a rapid release and high bioavailability of CS-NSP have also been verified in the study. Pharmacokinetic experiments in vivo showed that the bioavailability of CS-NSP was about 1.6 times that of commercial cefquinome sulfate injection (CS-INJ, Chuangdao®) (p< 0.01). These advantages of CS-NSP were carried out by small particle size and low viscosity, being associated with the use of Labrafac PG and stabilizer Labrasol. Conclusion: The results proved that the new preparation is safe and effective and is expected to become a promising veterinary nanodelivery system.
15 May 2019 in Polish Journal of Veterinary Sciences
The pharmacokinetics of a diclofenac sodium was investigated in swine. A single intravenous (i.v.) or intramuscular (i.m.) injection of 5% diclofenac sodium (concentration = 2.5 mg.kg(-1)) was administered to 8 healthy pigs according to a two-period crossover design. The pharmacokinetic parameters were calculated by non-compartmental analysis with DAS2.1.1 software. After a single i.v. administration, the main pharmacokinetic parameters of diclofenac sodium injection in swine were as follows: the elimination half-time (T-1/2 beta) was 1.32 +/- 0.34 h; the area under the curve (AUC) was (55.50 +/- 5.50 mu g.mL(-1) h; the mean residence time (MRT) was 1.60 +/- 0.28 h; the apparent volume of distribution (V-d) was 0.50 +/- 0.05 L.kg(-1); and the body clearance (CLB) was 0.26 +/- 0.04 L.(h.kg)(-1). After the single i.m. administration, the pharmacokinetic parameters were as follows: peak time (T-max) was 1.19 +/- 0.26 h; and peak concentration (C-max) was 11.61 +/- 5.99 mu g mL(-1). The diclofenac sodium has the following pharmacokinetic characteristics in swine: rapid absorption and elimination; high peak concentration; and bioavailability.