Glial growth factor 2 treatment alleviates ischemia and reperfusion-damaged integrity of the blood-brain barrier through decreasing Mfsd2a/caveolin-1-mediated transcellular and Pdlim5/YAP/TAZ-mediated paracellular permeability.

The impairment of blood-brain barrier (BBB) integrity is the pathological basis of hemorrhage transformation and vasogenic edema following thrombolysis and endovascular therapy. There is no approved drug in the clinic to reduce BBB damage after acute ischemic stroke (AIS). Glial growth factor 2 (GGF2), a recombinant version of neuregulin-1ß that can stimulates glial cell proliferation and differentiation, has been shown to alleviate free radical release from activated microglial cells. We previously found that activated microglia and proinflammatory factors could disrupt BBB after AIS. In this study we investigated the effects of GGF2 on AIS-induced BBB damage as well as the underlying mechanisms. Mouse middle cerebral artery occlusion model was established: mice received a 90-min ischemia and 22.5 h reperfusion (I/R), and were treated with GGF2 (2.5, 12.5, 50 ng/kg, i.v.) before the reperfusion. We showed that GGF2 treatment dose-dependently decreased I/R-induced BBB damage detected by Evans blue (EB) and immunoglobulin G (IgG) leakage, and tight junction protein occludin degradation. In addition, we found that GGF2 dose-dependently reversed AIS-induced upregulation of vesicular transcytosis increase, caveolin-1 (Cav-1) as well as downregulation of major facilitator superfamily domain containing 2a (Mfsd2a). Moreover, GGF2 decreased I/R-induced upregulation of PDZ and LIM domain protein 5 (Pdlim5), an adaptor protein that played an important role in BBB damage after AIS. In addition, GGF2 significantly alleviated I/R-induced reduction of YAP and TAZ, microglial cell activation and upregulation of inflammatory factors. Together, these results demonstrate that GGF2 treatment alleviates the I/R-compromised integrity of BBB by inhibiting Mfsd2a/Cav-1-mediated transcellular permeability and Pdlim5/YAP/TAZ-mediated paracellular permeability.

Expression and characterization of the new antimicrobial peptide AP138L-arg26 anti Staphylococcus aureus.

The low activity and yield of antimicrobial peptides (AMPs) are pressing problems. The improvement of activity and yield through modification and heterologous expression, a potential way to solve the problem, is a research hot-pot. In this work, a new plectasin-derived variant L-type AP138 (AP138L-arg26) was constructed for the study of recombination expression and druggablity. As a result, the total protein concentration of AP138L-arg26 was 3.1 mg/mL in Pichia pastoris X-33 supernatant after 5 days of induction expression in a 5-L fermenter. The recombinant peptide AP138L-arg26 has potential antibacterial activity against selected standard and clinical Gram-positive bacteria (G+, minimum inhibitory concentration (MIC) 2-16 µg/mL) and high stability under different conditions (temperature, pH, ion concentration) and 2 × MIC of AP138L-arg26 could rapidly kill Staphylococcus aureus (S. aureus) (> 99.99%) within 1.5 h. It showed a high safety in vivo and in vivo and a long post-antibiotic effect (PAE, 1.91 h) compared with vancomycin (1.2 h). Furthermore, the bactericidal mechanism was revealed from two dimensions related to its disruption of the cell membrane resulting in intracellular potassium leakage (2.5-fold higher than control), and an increase in intracellular adenosine triphosphate (ATP), and reactive oxygen species (ROS), the decrease of lactate dehydrogenase (LDH) and further intervening metabolism in S. aureus. These results indicate that AP138L-arg26 as a new peptide candidate could be used for more in-depth development in the future. KEY POINTS: • The AP138L-arg26 was expressed in the P. pastoris expression system with high yield • The AP138 L-arg26 showed high stability and safety in vitro and in vivo • The AP138L-arg26 killed S. aureus by affecting cell membranes and metabolism.

Pharmacokinetics and pharmacodynamics of antibacterial peptide NZX in Staphylococcus aureus mastitis mouse model.

Staphylococcus aureus is associated with dairy mastitis, which causes serious economic losses to dairy farming industry. Antibacterial peptide NZX showed good antibacterial activity against S. aureus. This study aimed to evaluate pharmacokinetics and pharmacodynamics of NZX against S. aureus-induced mouse mastitis. NZX exhibited potent in vitro antibacterial activity against the test S. aureus strains (minimal inhibitory concentration (MIC): 0.23-0.46 µM), low mutant prevention concentration (MPC: 1.18-3.68 µM), and a long post antibiotic effect (PAE: 2.20-8.84 h), which was superior to those of lincomycin and ceftiofur. Antibacterial mechanisms showed that NZX could penetrate the cell membrane, resulting in obvious cell membrane perforation and morphological changes, and bind to intracellular DNA. Furthermore, NZX had a good stability in milk environment (retention rate: 85.36%, 24 h) than that in mammary homogenate (47.90%, 24 h). In mouse mastitis model, NZX (25-400 µg/gland) could significantly reduce the bacterial load of mammary tissue in a dose-dependent manner. In addition, NZX (100 µg/gland) could relieve the inflammatory symptoms of mammary tissue, and significantly decreased its pathological scores. The concentration-time curve of NZX (100 µg/gland) in the mammary tissue was plotted and the corresponding pharmacokinetic parameters were obtained by non-compartment model calculation. Those parameters of Tmax, T1/2, Cmax and AUC were 0.5 h, 35.11 h, 32.49 µg/g and 391 µg·h/g, respectively. Therefore, these results suggest that NZX could act as a promising candidate for treating dairy mastitis disease caused by S. aureus. KEY POINTS: • NZX could kill S. aureus by dual mechanism involved in membrane and DNA disruption • NZX could relieve S. aureus-induced mouse mastitis • Pharmacokinetic parameters of NZX in mouse mammary gland were obtained.

Nuclear m(6)A Reader YTHDC1 Regulates mRNA Splicing.

The regulatory role of N(6)-methyladenosine (m(6)A) and its nuclear binding protein YTHDC1 in pre-mRNA splicing remains an enigma. Here we show that YTHDC1 promotes exon inclusion in targeted mRNAs through recruiting pre-mRNA splicing factor SRSF3 (SRp20) while blocking SRSF10 (SRp38) mRNA binding. Transcriptome assay with PAR-CLIP-seq analysis revealed that YTHDC1-regulated exon-inclusion patterns were similar to those of SRSF3 but opposite of SRSF10. In vitro pull-down assay illustrated a competitive binding of SRSF3 and SRSF10 to YTHDC1. Moreover, YTHDC1 facilitates SRSF3 but represses SRSF10 in their nuclear speckle localization, RNA-binding affinity, and associated splicing events, dysregulation of which, as the result of YTHDC1 depletion, can be restored by reconstitution with wild-type, but not m(6)A-binding-defective, YTHDC1. Our findings provide the direct evidence that m(6)A reader YTHDC1 regulates mRNA splicing through recruiting and modulating pre-mRNA splicing factors for their access to the binding regions of targeted mRNAs.

Expression of mitochondrial transcription factor A in granulosa cells: implications for oocyte maturation and in vitro fertilization outcomes.

OBJECTIVE: In vitro fertilization-embryo transfer (IVF-ET) is a widely used treatment for infertility, with oocyte maturation and quality having a significant impact on oocyte fertilization, embryo development, and fetal growth. Mitochondrial transcription factor A (TFAM) is essential for maintaining the mitochondrial oxidative respiratory chain and supplying energy for oocyte development, fertilization, and embryonic development. In this study, we aimed to examine TFAM expression in women undergoing IVF-ET and assess its impact on the IVF outcomes. METHODS: We recruited 85 women who underwent IVF-ET treatment for infertility. On the date of egg collection, granulosa cells were extracted from the clear follicular fluid of the first mature egg using ultrasound-guided needle aspiration. The collected granulosa cells served three purposes: (1) detecting TFAM gene expression in granulosa cells via immunocytochemistry, (2) determining TFAM mRNA expression using reverse transcription-PCR (RT-PCR), and (3) measuring TFAM protein expression through western blotting. RESULT: Based on the results, we found that TFAM was localized and expressed in the cytoplasm of granulosa cells, whereas no expression was detected in the nucleus. Granulosa cells exhibited a linear correlation between TFAM mRNA and TFAM protein expression. The study participants were divided into three groups using the ternary method based on relative TFAM mRNA expression thresholds of 33% and 76%: the low-expression group (n = 30), the moderate-expression group (n = 27), and the high-expression group (n = 28). When compared to the other two groups, the moderate expression group exhibited a significantly higher egg utilization rate, 2 pronucleus rate, fertilization rate, and clinical pregnancy rate (P < 0.05). CONCLUSION: TFAM was detected in the cytoplasm of human ovarian granulosa cells. Women with moderate TFAM expression demonstrate enhanced outcomes in IVF.

Rapid shifts in thermal reaction norms and tolerance of brooded coral larvae following parental heat acclimation.

Thermal priming of reef corals can enhance their heat tolerance; however, the legacy effects of heat stress during parental brooding on larval resilience remain understudied. This study investigated whether preconditioning adult coral Pocillopora damicornis to high temperatures (29°C and 32°C) could better prepare their larvae for heat stress. Results showed that heat-acclimated adults brooded larvae with reduced symbiont density and shifted thermal performance curves. Reciprocal transplant experiments demonstrated higher bleaching resistance and better photosynthetic and autotrophic performance in heat-exposed larvae from acclimated adults compared to unacclimated adults. RNA-seq revealed strong cellular stress responses in larvae from heat-acclimated adults that could have been effective in rescuing host cells from stress, as evidenced by the widespread upregulation of genes involved in cell cycle and mitosis. For symbionts, a molecular coordination between light harvesting, photoprotection and carbon fixation was detected in larvae from heat-acclimated adults, which may help optimize photosynthetic activity and yield under high temperature. Furthermore, heat acclimation led to opposing regulations of symbiont catabolic and anabolic pathways and favoured nutrient translocation to the host and thus a functional symbiosis. Notwithstanding, the improved heat tolerance was paralleled by reduced light-enhanced dark respiration, indicating metabolic depression for energy saving. Our findings suggest that adult heat acclimation can rapidly shift thermal tolerance of brooded coral larvae and provide integrated physiological and molecular evidence for this adaptive plasticity, which could increase climate resilience. However, the metabolic depression may be maladaptive for long-term organismal performance, highlighting the importance of curbing carbon emissions to better protect corals.

Effects of dietary supplementation of bovine lactoferrin on growth performance, immune function and intestinal health in weaning piglets.

Weaning is a crucial period in the pig's life cycle, which is frequently followed by gastrointestinal (GI) infections, diarrhea and even death. This study focused on the impact of bovine lactoferrin (bLF) supplementation on the intestinal health of weaning piglets. Weaning piglets (Duroc × Landrace × Yorkshire, 23 days) were randomly allocated into four groups, which included negative control group (CON): basic diet; positive control group (ANT): basic diet + 20 mg/kg flavomycin + 100 mg/kg aureomycin; treatment group bLF-A: basic diet + 1 g/kg bLF; treatment group bLF-B: basic diet + 3 g/kg bLF. The result showed that dietary supplementation of bLF can improve growth performance and reduce diarrhea, which exhibits dose-dependency (P < 0.05). Compared with CON group, supplementation with bLF significantly improved immunity, and increased villus height and ratio of villus height/crypt depth at the small intestinal mucosa (P < 0.05). The mRNA expression of claudin-1, occludin and ZO-1 was greatly increased in the ileum of bLF group on days 7 and 14 (P < 0.05). Furthermore, the supplementation of bLF increased the abundance of Lactobacillus and Bifidobacterium and decreased the abundance of Escherichia coli in the cecum on day 7 (P < 0.05). The dietary supplementation of bLF enhanced the growth performance, reduced diarrhea rate in weaning piglets by improving intestinal immunity, morphology and barrier function, balancing intestinal microbiota. And bLF can be a promising feed additive in relieving stress situation of weaning piglets.

High-Yield Preparation of American Oyster Defensin (AOD) via a Small and Acidic Fusion Tag and Its Functional Characterization.

The marine peptide, American oyster defensin (AOD), is derived from Crassostrea virginica and exhibits a potent bactericidal effect. However, recombinant preparation has not been achieved due to the high charge and hydrophobicity. Although the traditional fusion tags such as Trx and SUMO shield the effects of target peptides on the host, their large molecular weight (12-20 kDa) leads to the yields lower than 20% of the fusion protein. In this study, a short and acidic fusion tag was employed with a compact structure of only 1 kDa. Following 72 h of induction in a 5 L fermenter, the supernatant exhibited a total protein concentration of 587 mg/L. The recombinant AOD was subsequently purified through affinity chromatography and enterokinase cleavage, resulting in the final yield of 216 mg/L and a purity exceeding 93%. The minimum inhibitory concentrations (MICs) of AOD against Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus galactis ranged from 4 to 8 µg/mL. Moreover, time-killing curves indicated that AOD achieved a bactericidal rate of 99.9% against the clinical strain S. epidermidis G-81 within 0.5 h at concentrations of 2× and 4× MIC. Additionally, the activity of AOD was unchanged after treatment with artificial gastric fluid and intestinal fluid for 4 h. Biocompatibility testing demonstrated that AOD, at a concentration of 128 µg/mL, exhibited a hemolysis rate of less than 0.5% and a cell survival rate of over 83%. Furthermore, AOD's in vivo therapeutic efficacy against mouse subcutaneous abscess revealed its capability to restrain bacterial proliferation and reduce bacterial load, surpassing that of antibiotic lincomycin. These findings indicate AOD's potential for clinical usage.

Perspective: A proposal on solutions of modern supply chain construction for lactoferrin.

Lactoferrin is an iron-binding glycoprotein of the transferrin family that is found in most bodily fluids of mammals and has a variety of biological and beneficial functions, with great importance in health enhancement as a supplement for humans and other animals. More than 300 t of lactoferrin were produced in 2021, and this number is expected to grow yearly by 10% to 12%, to over 580 t in 2030. With new and important functions of lactoferrin being revealed and studied, focus on its industrial production and application is increasing accordingly. However, lactoferrin is mainly sourced from cheese whey or skim milk by cation-exchange column chromatography, which is a costly and low-quality method. A potential solution for lactoferrin global supply chain construction is proposed in this article as a complement to traditional routes of purification from whey or skim milk. The large-scale production of lactoferrin, mainly by recombinant yeast, mammal, and grain systems, as well as the market niche and product design, are discussed.

Bone marrow mesenchymal stem cell-derived exosomal miR-30e-5p ameliorates high-glucose induced renal proximal tubular cell pyroptosis by inhibiting ELAVL1.

BACKGROUND: The rapid increase in the prevalence of diabetes has resulted in more cases of diabetic kidney disease (DKD). Treatment with bone marrow mesenchymal stem cells (BMSCs) may represent an alternative strategy to manage DKD. METHODS: HK-2 cells were treated with 30 mM high glucose (HG). Bone marrow MSC-derived exosomes (BMSC-exos) were isolated and internalized into HK-2 cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and lactate dehydrogenase (LDH) assays were used to measure viability and cytotoxicity. The secretion of IL-1ß and IL-18 was measured by ELISA. Pyroptosis was assessed by flow cytometry. Quantitative RT-PCR was used to measure the levels of miR-30e-5p, ELAV like RNA binding protein 1 (ELAVL1), IL-1ß, and IL-18. The expression of ELAVL1 and pyroptosis-associated cytokine proteins was determined by western blot analysis. A dual-luciferase reporter gene assay was conducted to confirm the relationship between miR-30e-5p and ELAVL1. RESULTS: BMSC-exos decreased LDH, IL-1ß, and IL-18 secretion and inhibited the expression of the pyroptosis-related factors (IL-1ß, caspase-1, GSDMD-N, and NLRP3) in HG-induced HK-2 cells. Moreover, miR-30e-5p depletion derived from BMSC-exos promoted HK-2 cell pyroptosis. Besides, miR-30e-5p over-expression or ELVAL1 knockdown could directly inhibit pyroptosis. ELAVL1 was a target of miR-30e-5p and knocking down ELAVL1 reversed the effect of miR-30e-5p inhibition in BMSC-exos-treated HK-2 cells. CONCLUSIONS: BMSC-derived exosomal miR-30e-5p inhibits caspase-1-mediated pyroptosis by targeting ELAVL1 in HG-induced HK-2 cells, which might provide a new strategy for treating DKD.

Thinking on the Construction of Antimicrobial Peptide Databases: Powerful Tools for the Molecular Design and Screening.

With the accelerating growth of antimicrobial resistance (AMR), there is an urgent need for new antimicrobial agents with low or no AMR. Antimicrobial peptides (AMPs) have been extensively studied as alternatives to antibiotics (ATAs). Coupled with the new generation of high-throughput technology for AMP mining, the number of derivatives has increased dramatically, but manual running is time-consuming and laborious. Therefore, it is necessary to establish databases that combine computer algorithms to summarize, analyze, and design new AMPs. A number of AMP databases have already been established, such as the Antimicrobial Peptides Database (APD), the Collection of Antimicrobial Peptides (CAMP), the Database of Antimicrobial Activity and Structure of Peptides (DBAASP), and the Database of Antimicrobial Peptides (dbAMPs). These four AMP databases are comprehensive and are widely used. This review aims to cover the construction, evolution, characteristic function, prediction, and design of these four AMP databases. It also offers ideas for the improvement and application of these databases based on merging the various advantages of these four peptide libraries. This review promotes research and development into new AMPs and lays their foundation in the fields of druggability and clinical precision treatment.

Novel Lanthanide Complexes Synthesized from 3-Dimethylamino Benzoic Acid and 5,5'-Dimethyl-2,2' Bipyridine Ligand: Crystal Structure, Thermodynamics, and Fluorescence Properties.

Two isostructural lanthanide complexes were synthesized by solvent evaporation with 3-dimethylaminobenzoic acid and 5,5'-dimethyl-2,2'-bipyridine as ligands. The general formula of the structure is a [Ln(3-N,N-DMBA)3(5,5'-DM-2,2'-bipy)]2·2(3-N,N-DMHBA), Ln = (Gd(1), Tb(2)), 3-N,N-DMBA = 3-Dimethylamino benzoate, 5,5'-DM-2,2'-bipy = 5,5'-dimethyl-2,2' bipyridine. Both complexes exhibited dimeric structures based on X-ray diffraction analysis. At the same time, infrared spectroscopy and Raman spectroscopy were used to measure the spectra of the complex. A thermogravimetric infrared spectroscopy experiment was performed to investigate the thermal stability and decomposition mechanism of the complexes. Measurements of the low-temperature heat capacity of the complexes were obtained within the temperature range of 1.9 to 300 K. The thermodynamic function was calculated by heat capacity fitting. In addition, the fluorescence spectra of complex 2 were studied and the fluorescence lifetime values were determined, and the energy transfer mechanism of complex 2 was elucidated.

UV Disinfection Robots: A Review.

The novel coronavirus (COVID-19) pandemic has completely changed our lives and how we interact with the world. The pandemic has brought about a pressing need to have effective disinfection practices that can be incorporated into daily life. They are needed to limit the spread of infections through surfaces and air, particularly in public settings. Most of the current methods utilize chemical disinfectants, which can be laborious and time-consuming. Ultraviolet (UV) irradiation is a proven and powerful means of disinfection. There has been a rising interest in the implementation of UV disinfection robots by various public institutions, such as hospitals, long-term care homes, airports, and shopping malls. The use of UV-based disinfection robots could make the disinfection process faster and more efficient. The objective of this review is to equip readers with the necessary background on UV disinfection and provide relevant discussion on various aspects of UV robots.

Transient inhibition of CDK2 activity prevents oocyte meiosis I completion and egg activation in mouse.

Mammalian oocytes are arrested at the diplotene stage of prophase I during fetal or postnatal development. It was reported that cyclin-dependent kinases (CDK1) was the sole CDK to drive the resumption of meiosis and CDK2 was dispensable for meiosis progression in mouse oocytes according to the conditional knockout studies. However, a recent study showed that CDK2 activity is essential for meiotic division and gametogenesis by means of gene-directed mutagenesis, which avoids the compensatory activation of other CDKs. Taken the compensatory effect between CDKs after gene knockout, the physiological function of CDK2 activity in oocyte maturation remains unclear. To address this issue, we applied a specific small-molecule inhibitor to restrain CDK2 activity transiently during oocyte meiotic maturation. Surprisingly, transient inhibition of CDK2 activity severely prevented the meiosis I completion although the meiotic resumption was not affected. Then we found that CDK2 activity was required for establishment of normal spindle and chromosome dynamics. Notably, CDK2 inhibition interrupted the anaphase-promoting complex/cyclosome (APC/C)-dependent degradation pathway by maintaining the activation of spindle assembly checkpoint (SAC). Interestingly, CDK2 inhibition prevented the egg activation as well. Overall, our data demonstrate that CDK2 kinase activity is required for proper dynamics of spindle and chromosomes, whose disturbance induces the continuous SAC activation and subsequent inactivation of APC/C activity in oocyte meiosis.

Paclitaxel-based supramolecular hydrogel loaded with mifepristone for the inhibition of breast cancer metastasis.

Breast cancer is the leading cause of cancer death among women and almost all of the breast cancer-caused mortality is related to metastasis. It has been reported that glucocorticoid facilitates the metastasis of breast cancer in mice, and mifepristone can antagonize the effect of glucocorticoid. Paclitaxel is one of the important drugs in the treatment of breast cancer. Mifepristone combined with paclitaxel could be an effective strategy for inhibiting breast cancer metastasis. However, their inherent defects, in terms of short blood circulation half-life and lack of tumor targeting, not only limit their effectiveness but also cause adverse reactions. Therefore, our aim is to explore a novel protocol against breast cancer metastasis, further optimize its therapeutic efficacy by a nanodelivery system, and explore its mechanism. Herein, a paclitaxel-conjugated and mifepristone-loaded hydrogel (PM-nano) was prepared by self-assembly. Its characterizations were studied. The antimetastatic effect was evaluated in vitro and in vivo and its mechanism was also explored by western blot assay. The resultant PM-nano was developed with favorable water solubility and good biocompatibility. Moreover, PM-nano displayed increased cell uptake properties and stimulated drug release in the tumor micro-acidic environment. The PM-nano was more effective in inhibiting the proliferation and metastasis of breast cancer than other groups in vitro and in vivo. The PM-nano might inhibit metastasis through glucocorticoid receptor/receptor tyrosine kinase-like orphan receptor 1 and MMPs. Taken together, PM-nano showed superior antimetastatic effects against breast cancer and excellent biocompatibility in vitro and in vivo, providing a new option for limiting metastasis.

C-terminal mini-PEGylation of a marine peptide N6 had potent antibacterial and anti-inflammatory properties against Escherichia coli and Salmonella strains in vitro and in vivo.

BACKGROUND: Enteropathogenic Escherichia coli and Salmonella pullorum are two important groups of zoonotic pathogens. At present, the treatment of intestinal pathogenic bacteria infection mainly relies on antibiotics, which directly inhibit or kill the pathogenic bacteria. However, due to long-term irrational, excessive use or abuse, bacteria have developed different degrees of drug resistance. N6, an arenicin-3 derivative isolated from the lugworm, has potent antibacterial activity and is poorly resistant to enzymatic hydrolysis and distribution in vivo. Polyethylene glycol (PEG) is an extensively studied polymer and commonly used in protein or peptide drugs to improve their therapeutic potential. Here, we modified the N-/C-terminal or Cys residue of N6 with liner PEGn of different lengths (n = 2, 6,12, and 24), and the effects of PEGylation of N6 on the stability, toxicity, bactericidal mechanism, distribution and efficacy were investigated in vitro and in vivo. RESULTS: The antimicrobial activity of the peptide showed that PEGylated N6 at the C-terminus (n = 2, N6-COOH-miniPEG) had potent activity against Gram-negative bacteria; PEGylated N6 at the N-terminus and Cys residues showed low or no activity with increasing lengths of PEG. N6-COOH-miniPEG has higher stability in trypsin than the parent peptide-N6. N6-COOH-miniPEG significantly regulated cytokine expression in lipopolysaccharides (LPS)-induced RAW 264.7 cells, and the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß were reduced by 31.21%, 65.62% and 44.12%, respectively, lower than those of N6 (-0.06%, -12.36% and -12.73%); N6-COOH-miniPEG increased the level of IL-10 (37.83%), higher than N6 (-10.21%). The data indicated that N6-COOH-miniPEG has more potent anti-inflammatory and immune-regulatory effect than N6 in LPS-stimulated RAW 264.7 cells. N6-COOH-miniPEG exhibited a much wider biodistribution in mice and prolonged in vivo half-time. FITC-labeled N6-COOH-miniPEG was distributed throughout the body of mice in the range of 0.75 - 2 h after injection, while FITC-labeled N6 only concentrated in the abdominal cavity of mice after injection, and the distribution range was narrow. N6-COOH-miniPEG improved the survival rates of mice challenged with E. coli or S. pullorum, downregulated the levels of TNF-α, IL-6, IL-1ß and IL-10 in the serum of LPS-infected mice, and alleviated multiple-organ injuries (the liver, spleen, kidney, and lung), superior to antibiotics, but slightly inferior to N6. CONCLUSIONS: The antibacterial activity, bactericidal mechanism and cytotoxicity of N6-COOH-miniPEG and N6 were similar. N6-COOH-miniPEG has a higher resistance to trysin than N6. The distribution of N6-COOH-miniPEG in mice was superior to that of N6. In exploring the modulatory effects of antimicrobial peptides on cytokines, N6-COOH-miniPEG had stronger anti-inflammatory and immunomodulatory effects than N6. The results suggested that C-terminal PEGylated N6 may provide an opportunity for the development of effective anti-inflammatory and antibacterial peptides.

Clinical characteristics and prognostic factors of anal adenocarcinoma: a nomogram development based on SEER database and validation in the WCH database.

PURPOSE: The purpose of this study was to comprehensively understand anal canal adenocarcinomas (AA) and develop a nomogram for prognostic prediction of AA. METHODS: Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database (the year 2004-2015). An external validation set was collected from West China Hospital (WCH) databases. Propensity-score matching (PSM) was performed to balance the demographic characteristic. A novel nomogram was developed to estimate individual survival probability and its performance was validated using the concordance index (C-index), calibration curves, and decision curve analyses (DCA). RESULTS: A total of 7901 patients were enrolled including 749 AA patients and 7152 squamous cell carcinomas of the anal canal (ASCC) patients. Before PSM, patients with AA had shorter cancer-specific survival (CSS) and OS than those with ASCC. However, after PSM, patients with AA were related to a favorable OS (p < 0.001), but a comparable CSS (p = 0.140) to those with ASCC. Age, sex, grade, surgery, and M stage were the independent prognostic factors of CSS for AA and were included in the establishment of a novel nomogram. Patients from the WCH database (n = 112) were used as an external validation cohort. The C-index of the nomogram was 0.78 and 0.735 in internal and external validation, respectively, which suggested the good discrimination power of the model. Furthermore, calibration curves and DCA suggested good agreement between the predicted and actual survival. Lastly, a risk classification system based on a nomogram revealed the reliability of the novel model. CONCLUSION: AA and ASCC had distinct clinical features. AA was associated with a better prognosis than ASCC after PSM. The model of nomogram showed an accurate predictive ability for prognostic factors of AA patients.

Pharmacological characterization of a novel metal-based proteasome inhibitor Na-AuPT for cancer treatment.

The ubiquitin-proteasome system (UPS) is essential for maintaining cell homeostasis by orchestrating the protein degradation, but is impaired in various diseases, including cancers. Several proteasome inhibitors, such as bortezomib, are currently used in cancer treatment, but associated toxicity limits their widespread application. Recently metal complex-based drugs have attracted great attention in tumor therapy; however, their application is hindered by low water-solubility and poor absorbency. Herein, we synthesized a new type of gold (I) complex named Na-AuPT, and further characterized its anticancer activity. Na-AuPT is highly water-soluble (6 mg/mL), and it was able to potently inhibit growth of a panel of 11 cancer cell lines (A549, SMMC7721, H460, HepG2, BEL7402, LNCap, PC3, MGC-803, SGC-7901, U266, and K562). In A549 and SMMC7721 cells, Na-AuPT (in a range of 2.5-20 µM) inhibited the UPS function in a dose-dependent fashion by targeting and inhibiting both 20 S proteasomal proteolytic peptidases and 19 S proteasomal deubiquitinases. Furthermore, Na-AuPT induced caspase-dependent apoptosis in A549 and SMMC7721 cells, which was prevented by the metal chelator EDTA. Administration of Na-AuPT (40 mg · kg-1 · d-1, ip) in nude mice bearing A549 or SMMC7721 xenografts significantly inhibited the tumor growth in vivo, accompanied by increased levels of total ubiquitinated proteins, cleaved caspase 3 and Bax protein in tumor tissue. Moreover, Na-AuPT induced cell death of primary mononuclear cells from 5 patients with acute myeloid leukemia ex vivo with an average IC50 value of 2.46 µM. We conclude that Na-AuPT is a novel metal-based proteasome inhibitor that may hold great potential for cancer therapy.

Antibacterial peptide NZ2114-loaded hydrogel accelerates Staphylococcus aureus-infected wound healing.

Wound infection caused by Staphylococcus aureus (S. aureus) is a great challenge which has caused significant burden and economic loss to the medical system. NZ2114, a plectasin-derived peptide, is an antibacterial agent for preventing and treating S. aureus infection, especially for methicillin-resistant S. aureus (MRSA) infection. Here, three-dimensional reticulated antimicrobial peptide (AMP) NZ2114 hydrogels were developed based on hydroxypropyl cellulose (HPC) and sodium alginate (SA); they displayed sustained and stable release properties (97.88 ± 1.79% and 91.1 ± 10.52% release rate in 72 h, respectively) and good short-term cytocompatibility and hemocompatibility. But the HPC-NZ2114 hydrogel had a smaller pore size (diameter 0.832 ± 0.420 µm vs. 3.912 ± 2.881 µm) and better mechanical properties than that of the SA-NZ2114 hydrogel. HPC/SA-NZ2114 hydrogels possess efficient antimicrobial activity in vitro and in vivo. In a full-thickness skin defect model, the wound closure of the 1.024 mg/g HPC-NZ2114 hydrogel group was superior to those of the SA-NZ2114 hydrogel and antibiotic groups on day 7. The HPC-NZ2114 hydrogel accelerated wound healing by reducing inflammation and promoting the production of vascular endothelial growth factor (VEGF), endothelial growth factor (EGF) and angiogenesis (CD31) through histological and immunohistochemistry evaluation. These data indicated that the HPC-NZ2114 hydrogel is an excellent candidate for S. aureus infection wound dressing. KEY POINTS: •NZ2114 hydrogels showed potential in vitro bactericidal activity against S. aureus •NZ2114 hydrogels could release continuously for 72 h and had good biocompatibility •NZ2114 hydrogels could effectively promote S. aureus-infected wound healing.

Resistance response to Arenicin derivatives in Escherichia coli.

The rising prevalence of antibiotic resistance poses the greatest health threats. Antimicrobial peptides (AMPs) are regarded as the potentially effective therapy. To avoid current crisis of antibiotic resistance, a comprehensive understanding of AMP resistance is necessary before clinical application. In this study, the development of resistance to the anti-Gram-negative bacteria peptide N6NH2 (21 residues, ß-sheet) was characterized in E. coli ATCC25922. Three N6NH2-resistant E. coli mutants with 32-fold increase in MIC were isolated by serially passaging bacterial lineages in progressively increasing concentrations of N6NH2 and we mainly focus on the phenotype of N6NH2-resistant bacteria different from sensitive bacteria. The results showed that the resistance mechanism was attributed to synergy effect of multiple mechanisms: (i) increase biofilm formation capacity (3 ~ 4-fold); (ii) weaken the affinity of lipopolysaccharide (LPS) with N6NH2 (3 ~ 8-fold); and (iii) change the cell membrane permeability and potential. Interestingly, a chimeric peptide-G6, also a N6NH2 analog, which keep the same antibacterial activity to both wild-type and resistant clones (MIC value: 16 µg/mL), could curb N6NH2-resistant mutants by stronger inhibition of biofilm formation, stronger affinity with LPS, and stronger membrane permeability and depolarization than that of N6NH2.