Mitochondrial GPX4 acetylation is involved in cadmium-induced renal cell ferroptosis.

Increasing evidences demonstrate that environmental stressors are important inducers of acute kidney injury (AKI). This study aimed to investigate the impact of exposure to Cd, an environmental stressor, on renal cell ferroptosis. Transcriptomics analyses showed that arachidonic acid (ARA) metabolic pathway was disrupted in Cd-exposed mouse kidneys. Targeted metabolomics showed that renal oxidized ARA metabolites were increased in Cd-exposed mice. Renal 4-HNE, MDA, and ACSL4, were upregulated in Cd-exposed mouse kidneys. Consistent with animal experiments, the in vitro experiments showed that mitochondrial oxidized lipids were elevated in Cd-exposed HK-2 cells. Ultrastructure showed mitochondrial membrane rupture in Cd-exposed mouse kidneys. Mitochondrial cristae were accordingly reduced in Cd-exposed mouse kidneys. Mitochondrial SIRT3, an NAD+-dependent deacetylase that regulates mitochondrial protein stability, was reduced in Cd-exposed mouse kidneys. Subsequently, mitochondrial GPX4 acetylation was elevated and mitochondrial GPX4 protein was reduced in Cd-exposed mouse kidneys. Interestingly, Cd-induced mitochondrial GPX4 acetylation and renal cell ferroptosis were exacerbated in Sirt3-/- mice. Conversely, Cd-induced mitochondrial oxidized lipids were attenuated in nicotinamide mononucleotide (NMN)-pretreated HK-2 cells. Moreover, Cd-evoked mitochondrial GPX4 acetylation and renal cell ferroptosis were alleviated in NMN-pretreated mouse kidneys. These results suggest that mitochondrial GPX4 acetylation, probably caused by SIRT3 downregulation, is involved in Cd-evoked renal cell ferroptosis.

Arsenic exposure causes decline in sperm motility accompanied by energy metabolism disorders in mouse testes.

Arsenic (As) is a notorious environmental toxicant widely present in various natural environments. As exposure has been correlated with the decline in sperm motility. Yet, the mechanism has not been fully elucidated. Adult male C57 mice were given 0, 1, or 15 mg/L NaAsO2 for 10 weeks. The mature seminiferous tubules and sperm count were decreased in As-exposed mice. Sperm motility and several sperm motility parameters, including average path velocity (VAP), straight-line velocity (VSL), curvilinear velocity (VCL), beat-cross frequency (BCF), linearity (LIN), straightness (STR), and amplitude of lateral head displacement (ALH), were declined in As-exposed mice. RNA sequencing and transcriptomics analyses revealed that differentially expressed genes (DEGs) were mainly enriched in metabolic pathways. Untargeted metabolomics analyses indicated that energy metabolism was disrupted in As-exposed mouse testes. Gene set enrichment analysis showed that glycolysis and oxidative phosphorylation were disturbed in As-exposed mouse testes. As-induced disruption of testicular glucose metabolism and oxidative phosphorylation was further validated by RT-PCR and Western blotting. In conclusion, As exposure causes decline in sperm motility accompanied by energy metabolism disorders in mouse testes.

Outcomes of antiretroviral treatment for 0-14-year-old children living with HIV in Ganzhou, China, 2006-2023.

BACKGROUND: Studies on antiretroviral therapy (ART) in children living with HIV (CLHIV) are limited due to the small population and low accession rate of ART. METHODS: All 0-14-year-old CLHIV admitted to the Ganzhou Center for Disease Control and Prevention from January 2006 to June 2023 were included retrospectively. The information of treatment regimens, disease progression, and laboratory tests of the patients under ART were used to explore the outcomes and impacts of long-term ART. The normality of all the data was tested by the Shapiro-Wilk test. RESULTS: From 2006 to 2023, 18 CLHIV were reported in Ganzhou. Among them, 11 received ART and were followed up for 60.0 ± 48.4 months. After receiving ART, the median viral load of them decreased from 89,600 copies/ml to 22 copies/ml (P = 0.007), the median CD4+ T cell count increased from 380.7 cells/µL to 661.9 cells/µL (P = 0.028), and the median CD8+ T cell count decreased from 1065.8 cells/µL to 983.3 cells/µL (P = 0.584). The laboratory test results regarding liver function, renal function, blood cell count, and glucolipid metabolism tended to be within normal reference ranges, and the mean height-for-age z-score and weight-for-age z-score increased. However, all the three CLHIV who received cotrimoxazole developed pneumocystis carinii pneumonia, upper respiratory infection, skin lesions, bacterial pneumonia and/or thrush; the mean body-mass-index-for-age z-score decreased from 0.52 to -0.63. CONCLUSION: For CLHIV, ART could effectively inhibit the replication of HIV and improve the immune function of patients. More studies that focus on ART in CLHIV are urgently needed.

Medulla Tetrapanacis water extract alleviates inflammation and infection by regulating macrophage polarization through MAPK signaling pathway.

Medulla Tetrapanacis (MT) is a commonly used herb to promote lactation and manage mastitis in lactating mothers. However, its anti-inflammatory and anti-bacterial effects are currently unknown. We hypothesized that MT water extract possesses anti-inflammatory and anti-bacterial effects by modulating macrophage polarization to reduce the release of inflammatory mediators and phagocytosis via inactivation of MAPKs pathways. The chemical composition of the MT water extract was analyzed by UPLC-Orbitrap-mass spectrometry. The anti-inflammatory and anti-bacterial properties of the MT water extract were examined using LPS-stimulated inflammation and Staphylococcus aureus infection model in RAW 264.7 cells, respectively. The underlying mechanism of action of the MT water extract was also investigated. We identified eight compounds by UPLC-Orbitrap-mass spectrometry that are abundant within the MT water extract. MT water extract significantly suppressed LPS-induced nitric oxide, TNF-α and IL-6 secretion in RAW 264.7 cells which was accompanied by the promotion of macrophage polarization from pro-inflammatory towards anti-inflammatory phenotypes. MT water extract significantly suppressed the LPS-induced MAPK activation. Finally, MT water extract decreased the phagocytic capacity of the RAW 264.7 cells against S. aureus infection. MT water extract could suppress LPS-induced inflammation by promoting macrophages towards an anti-inflammatory phenotype. In addition, MT also inhibited the growth of S. aureus.

3-Hydroxypyridin-4(1H)-one Derivatives as pqs Quorum Sensing Inhibitors Attenuate Virulence and Reduce Antibiotic Resistance in Pseudomonas aeruginosa.

The development of quorum sensing inhibitors capable of decreasing the production of virulence factors is an effective strategy to overcome resistance in Pseudomonas aeruginosa due to the less selective pressure exerted on bacteria. In this study, a series of 3-hydroxypyridin-4(1H)-one derivatives bearing a 4-aminomethyl-1,2,3-triazole linker were designed and synthesized as antivirulence agents against P. aeruginosa. The most potent derivative 16e was identified as a selective inhibitor of the pqs system (IC50 = 3.7 µM) and its related virulence factor pyocyanin (IC50 = 2.7 µM). In addition, 16e exhibited moderate biofilm inhibition and significant inhibition of P. aeruginosa motility phenotypes with low cytotoxicity. Compound 16e showed an obvious antibacterial synergistic effect in combination with antibiotics such as ciprofloxacin and tobramycin in in vitro and in vivo Caenorhabditis elegans infection models. Overall, the excellent antivirulence properties of compound 16e make it a potential antibiotic adjuvant for the treatment of P. aeruginosa infections that may be advanced into preclinical development in the future.

[PKEP with complete preservation of the urethral mucosa in the 11－1 o'clock position improves urinary continence and protects erectile function in BPH patients].

OBJECTIVE: To evaluate the effect of transurethral plasmakinetic enucleation of the prostate (PKEP) with complete preservation of the urethral mucosa in the 11－1 o'clock position on urinary continence and erectile function in BPH patients. METHODS: We retrospectively analyzed the clinical data on 84 cases of BPH treated by traditional PKEP (group A, n = 48) or modified PKEP with complete preservation of the urethral mucosa in the 11－1 o'clock position (group B, n = 36) from January 2017 to December 2021. All the patients had sexual activities within three months preoperatively. We followed up the patients for 12 months after surgery and compared the baseline, surgery-related and follow-up data between the two groups of patients. RESULTS: There were no statistically significant differences between the two groups of patients in age, disease duration, prostate volume, preoperative postvoid residual urine (PVR), preoperative maximum urinary flow rate (Qmax), IPSS, PSA level, QOL scores or IIEF-5 scores, nor in the operation time, intraoperative hemoglobin decrease, volume of resected tissue, bladder flushing time, postoperative hospital stay, or postoperative improvement of Qmax and IPSS. The rate of urinary continence was significantly higher in group B than in A at 1 month postoperatively (66.67% ï¼»24/36ï¼½ vs 43.25% ï¼»20/48ï¼½, P = 0.025) and so were IIEF-5 scores at 6 months (16.69 ± 3.21 vs 15.27 ± 2.74, P = 0.032) and 12 months (18.04 ± 2.04 vs 16.96 ± 2.54, P = 0.039), while the incidence rate of retrograde ejaculation markedly lower in the former than in the latter group at 6 months (33.33% ï¼»12/36ï¼½ vs 56.25% ï¼»28/48ï¼½, P = 0.018) and 12 months (25% ï¼»9/36ï¼½ vs 47.92% ï¼»23/48ï¼½, P = 0.027). At 1, 3, 6 and 12 months after surgery, the patients in group B also showed remarkably higher QOL scores than those in group B (2.61 ± 0.81 vs 2.12 ± 0.69, P = 0.005; 2.24 ± 0.66 vs 1.94 ± 0.51,P = 0.026; 2.12 ± 0.83 vs 1.80 ± 0.53,P = 0.047; and 1.94 ± 0.65 vs 1.72 ± 0.58, P = 0.038). CONCLUSION: Modified PKEP with complete preservation of the urethral mucosa in the 11－1 o'clock position can improve urinary continence, protect erectile function and ameliorate QOL in patients with BPH.

Gastro­oesophageal reflux disease in liver cirrhosis: Possible pathogenesis and clinical intervention (Review).

Oesophageal variceal bleeding is a common complication of decompensated liver cirrhosis (LC). Some studies have reported that reflux oesophagitis (RE) is a risk factor for upper gastrointestinal bleeding, and greatly impacts the quality of life. However, the frequency and mechanism of gastro-oesophageal reflux disease (GERD) in LC remain unclear. The present review explored the possible pathogenesis, and analysed the advantages and disadvantages of the interventional measures and the need for implementation of these measures. By combining the comprehensive terms associated with LC, GERD and RE, EMBASE, Medline/PubMed and the Cochrane Library were systematically searched. The underlying pathological mechanism of GERD in LC was summarized: Transient relaxation of the lower oesophageal sphincter, delayed gastric emptying, increased intra-abdominal pressure, increased intragastric pressure and excessive nitric oxide production destroyed the 'anti-reflux barrier', causing gastric content reflux. Proton pump inhibitors (PPIs) have been widely used empirically to lower the risk of oesophageal venous rupture and bleeding. However, long-term use of acid inhibitors in patients with LC may induce complications, such as spontaneous bacterial peritonitis. The metabolic half-life of PPIs is prolonged in patients with severe liver function impairment. Therefore, the indications for using acid inhibitors lack clarity. However, after endoscopic oesophageal variceal eradication, additional benefits may be gained from the long-term use of PPIs in small doses.

Design, synthesis and biological evaluation of novel 3-hydroxypyridin-4(1H)-ones based hybrids as Pseudomonas aeruginosa biofilm inhibitors.

Pseudomonas aeruginosa (P. aeruginosa) is a gram-negative pathogenic bacterium, often causative drug-resistance related human infections, given its great capacity to form bioflm. It uses three major quorum sensing (QS) systems, las, rhl, and pqs, to regulate the expression of genes related to virulence and biofilm formation. Consequently, strategies for inhibiting QS have garnered considerable attention as antimicrobial therapies. In this study, we designed and synthesized several 3-hydroxypyridin-4(1H)-one hybrids and assessed their potential as the inhibitors of P. aeruginosa biofilm formation. The most active compound identified was 12h; it exhibited satisfactory biofilm inhibitory activity (IC50: 10.59 ± 1.17 µM). Mechanistic studies revealed that 12h significantly inhibited the fluorescence of the PAO1-lasB-gfp and PAO1-pqsA-gfp fluorescent reporter strains and the production of Las-regulated (elastase) and Pqs-regulated (pyocyanin) virulence factors. These findings indicate that 12h inhibited biofilm formation by suppressing the expression of lasB and pqsA, thereby inactivating the las and pqs pathways. Furthermore, 12h improved the antibiotic susceptibility of P. aeruginosa and reduced the acute virulence of this bacterium in the African green monkey kidney cell line Vero. In conclusion, 3-hydroxypyridin-4(1H)-one hybrids, such as 12h, represent a promising class of antibacterial agents against P. aeruginosa.

Quinpirole ameliorates nigral dopaminergic neuron damage in Parkinson's disease mouse model through activating GHS-R1a/D2R heterodimers.

Growth hormone secretagogue receptor 1a (GHS-R1a) is an important G protein-coupled receptor (GPCR) that regulates a variety of functions by binding to ghrelin. It has been shown that the dimerization of GHS-R1a with other receptors also affects ingestion, energy metabolism, learning and memory. Dopamine type 2 receptor (D2R) is a GPCR mainly distributed in the ventral tegmental area (VTA), substantia nigra (SN), striatum and other brain regions. In this study we investigated the existence and function of GHS-R1a/D2R heterodimers in nigral dopaminergic neurons in Parkinson's disease (PD) models in vitro and in vivo. By conducting immunofluorescence staining, FRET and BRET analyses, we confirmed that GHS-R1a and D2R could form heterodimers in PC-12 cells and in the nigral dopaminergic neurons of wild-type mice. This process was inhibited by MPP+ or MPTP treatment. Application of QNP (10 µM) alone significantly increased the viability of MPP+-treated PC-12 cells, and administration of quinpirole (QNP, 1 mg/kg, i.p. once before and twice after MPTP injection) significantly alleviated motor deficits in MPTP-induced PD mice model; the beneficial effects of QNP were abolished by GHS-R1a knockdown. We revealed that the GHS-R1a/D2R heterodimers could increase the protein levels of tyrosine hydroxylase in the SN of MPTP-induced PD mice model through the cAMP response element binding protein (CREB) signaling pathway, ultimately promoting dopamine synthesis and release. These results demonstrate a protective role for GHS-R1a/D2R heterodimers in dopaminergic neurons, providing evidence for the involvement of GHS-R1a in PD pathogenesis independent of ghrelin.

Design and Synthesis of 3-Hydroxy-pyridin-4(1H)-ones-Ciprofloxacin Conjugates as Dual Antibacterial and Antibiofilm Agents against Pseudomonas aeruginosa.

Pseudomonas aeruginosa infections are often complicated by the fact that it can easily form a biofilm that increases its resistance to antibiotics. Consequently, the development of novel antibacterial agents against biofilm-associated drug-resistant P. aeruginosa is urgently needed. Herein, we report a series of 3-hydroxy-pyridin-4(1H)-ones-ciprofloxacin conjugates that were designed and synthesized as dual antibacterial and antibiofilm agents against P. aeruginosa. A potential 2-substituted 3-hydroxy-1,6-dimethylpyridin-4(1H)-one-ciprofloxacin conjugate (5e) was identified and had the best minimum inhibitory concentrations of 0.86 and 0.43 µM against P. aeruginosa 27853 and PAO1 and reduced 78.3% of biofilm formation. In addition, 5e eradicates mature biofilms and kills living bacterial cells that are incorporated into the biofilm. Studies on the antibiofilm mechanism of conjugates showed that 5e interferes with iron uptake by bacteria, inhibits their motility, and reduces the production of virulence. These results demonstrate that 3-hydroxy-pyridin-4(1H)-ones-ciprofloxacin conjugates are potent in the treatment of biofilm-associated drug-resistant P. aeruginosa infections.

Inhalation of 4% and 67% hydrogen ameliorates oxidative stress, inflammation, apoptosis, and necroptosis in a rat model of glycerol-induced acute kidney injury.

Acute kidney injury (AKI) is the major complication of rhabdomyolysis (RM) clinically, which is usually mimicked by glycerol injection in basic research. Oxidative stress, inflammatory response and apoptosis are recognized to play important roles in development of this disease. Recently, numerous studies have reported the therapeutic effects of molecular hydrogen (H2) on oxidative stress and inflammation-related diseases. Here, the effects of H2 against glycerol-induced AKI and the underlying mechanisms were explored in rats. Low (4%) and high (67%) concentrations of H2 were prepared using a self-made device to investigate the dose-response. After 72 hours of glycerol injection (8 mL/kg), we found that glycerol triggered oxidative stress, inflammatory reactions, and apoptotic events. These caused subsequent renal damage, evidenced by a significant reduction of antioxidases and up-regulation of the relevant damaged biomarkers. H2 inhalation reversed the above alterations and exerted renoprotective effects. Interestingly, for RM/AKI-related factors, no consistent dose-response benefits of H2 were observed. However, higher concentration of H2 inhalation improved histological and morphological changes better. This study suggests that H2 is a potential alternative therapy to prevent or minimize RM induced AKI possibly via its antioxidant, anti-inflammatory, anti-apoptotic and anti-necroptotic properties.

Water-driven Successive Structural Transformation in a Two-Dimensional (2D) Lead-Free Hybrid Double Perovskite.

Hybrid organic-inorganic halide perovskites (HOIPs) have received continued interest for their structure diversity and potential application in optoelectronic, solar cells, nonlinear optics (NLO), and ferroelectrics. Structural symmetry breaking induced by water molecules in single-crystal-to-single-crystal (SCSC) transformations is beneficial to develop ferroelectrics or second-harmonic generation (SHG) materials. Along this line, a water-containing two-dimensional (2D) double perovskite, (C6H16N2)2AgBiBr8·H2O (1), was prepared. Acentric 1 suffered a twice SCSC transformation when subjected to dehydration and rehydration, where the new centric (C6H16N2)2AgBiBr8 (2) and acentric (C6H16N2)2AgBiBr8·0.5H2O (3) were generated. In contrast to the irreversible transformation from 1 to 2 (symmetry: P21 → Pmna), it is prominent that the reversible conversion of centric 2 to acentric 3 (symmetry: Pmna ↔ P21212). The result validated the effect of guest water on inducing structural transformation and symmetry breaking of 2D perovskites, inspiring further explorations on water-involved 2D materials.

Thermally induced charge transfer in a quinoid-bridged linear Cu3 compound.

Charge transfer always occurs in molecular valence tautomers, leading to the redistribution of electron density and exhibiting electrical, optical, and magnetic properties, and can be further controlled by multiple external stimuli such as temperature, light and electric field. The design of molecule-based materials capable of charge transfer remains a challenge. Herein, a linear Cu3 compound [(CH3)3NCH2CH2Br]2[Cu3L4(H2O)2] (H2L = chloranilic acid) (1) with a multi-center donor-acceptor architecture was constructed using the redox-active chloranilic acid quinoid ligand. Temperature-dependent dielectric measurement was performed to capture the charge transfer valence tautomer transition because it is difficult to detect this transition by crystal structure and magnetism analysis. Temperature-dependent XPS and EPR further confirmed that the charge transfer valence tautomer transition is based on the CuII-L2- to CuI-L-˙ multi-center charge transfer. Thus, the present work builds a charge transfer compound with a multi-center donor-acceptor architecture and proves that dielectric measurement is a very effective means to detect charge transfer.

Mitochondrial ROS-mediated ribosome stalling and GCN2 activation are partially involved in 1-nitropyrene-induced steroidogenic inhibition in testes.

In the past 50 years, testosterone (T) level in men has declined gradually. In this research, we discovered that acute exposure to 1-nitropyrene (1-NP), an environmental stressor from polluted atmosphere, reduced T contents by downregulating steroidogenic proteins in mouse testes and Leydig cells. Acute 1-NP exposure caused GCN2 activation and eIF2α phosphorylation, a marker of integrated stress, in mouse testes and Leydig cells. GCN2iB, a selective GCN2 kinase inhibitor, and siGCN2, the GCN2-targeted short interfering RNA, attenuated 1-NP-induced reduction of steroidogenic proteins in Leydig cells. Mechanistically, mitochondrial membrane potential was reduced and ATP5A, UQCRC2, SDHB and NDUFB8, four OXPHOS subunits, were reduced in 1-NP-exposed Leydig cells. Cellular mitochondrial respiration was inhibited and ATP production was reduced. Moreover, mitochondrial reactive oxygen species (ROS) were elevated in 1-NP-exposed Leydig cells. The interaction between GCN2 and uL10, a marker of ribosome stalling, was observed in 1-NP-exposed Leydig cells. MitoQ, a mitochondria-targeted antioxidant, attenuated1-NP-evoked ATP depletion and ribosome stalling in Leydig cells. Moreover, MitoQ suppressed 1-NP-caused GCN2 activation and eIF2α phosphorylation in Leydig cells. In addition, MitoQ alleviated 1-NP-induced steroidogenic inhibition in mouse testes. In conclusion, mitochondrial ROS-mediated ribosome stalling and GCN2 activation are partially involved in environmental stress-induced steroidogenic inhibition in testes.

[Anti-inflammatory active component in raw materials of Ligustici Rhizoma et Radix based on spectrum-effect relationship].

The present study investigated the correlation of UPLC fingerprints of raw materials of Ligustici Rhizoma et Radix samples with the anti-inflammatory effect and explored the pharmacodynamic material basis for the anti-inflammatory activity. UPLC fingerprints of 18 batches of raw materials of Ligustici Rhizoma et Radix samples were established for the determination of the content of eight components. The toe swelling rate and the content of IL-1ß, IL-6, and PGE2 in rats with toe inflammation induced by carrageenin were measured. Canonical correlation analysis was used to study the spectrum-effect relationship. Cluster analysis indicated that chemical components of Ligusticum sinense and L. jeholense were similar. Methanol extracts of L. sinense, L. jeholense, and Conioselinum vaginatum significantly reduced the toe swelling rate and the content of IL-1ß, IL-6 and PGE2 in swollen tissues. The anti-inflammatory effect of C. vaginatum was weaker than that of L. sinense and L. jeholense. The results of spectrum-effect relationship indicated that there was an obvious correlation between chemical components and pharmacodynamic indexes. In UPLC fingerprints, compounds 1, 3(chlorogenic acid), 4(cryptochlorogenic acid), 5, 6(ferulic acid), 7(isochlorogenic acid B), 9, 11, 13, 15, 16, 17, 18(coniferyl ferulate), 19, 20(N-butylphthalide), 21, 22, and 23 were significantly correlated with anti-inflammation, among which compounds 5, 11, 13, 15, 17, 21, and 23 had negative correlation. This study screened out the effective components with anti-inflammatory activity in raw materials of Ligustici Rhizoma et Radix, which was of great significance to improve the quality evaluation system of raw materials of Ligustici Rhizoma et Radix.

Molecular Structure and Phylogenetic Analyses of the Complete Chloroplast Genomes of Three Medicinal Plants Conioselinum vaginatum, Ligusticum sinense, and Ligusticum jeholense.

Most plants of Ligusticum have an important medicinal and economic value with a long history, Ligusticum sinense and L. jeholense ("Gaoben") has long been used in traditional Chinese medicine for the treatment of carminative, dispelling cold, dehumidification, and analgesia. While in the market Conioselinum vaginatum (Xinjiang Gaoben) is substitution for Gaoben, and occupies a higher market share. These three Gaoben-related medicinal materials are similar in morphology, and are difficult to distinguish from each other by the commonly used DNA barcodes. The chloroplast genome has been widely used for molecular markers, evolutionary biology, and barcoding identification. In this study, the complete chloroplast genome sequences of C. vaginatum, L. sinense, and L. jeholense were reported. The results showed that the complete chloroplast genomes of these three species have typical quadripartite structures, which were comprised of 148,664, 148,539, and 148,497 bp. A total of 114 genes were identified, including 81 protein-coding genes (PCGs), 29 tRNA genes, and four rRNA genes. Our study indicated that highly variable region ycf2-trnL and accD-ycf4 that can be used as specific DNA barcodes to distinguish and identify C. vaginatum, L. sinense, and L. jeholense. In addition, phylogenetic study showed that C. vaginatum nested in Ligusticum and as a sister group of L. sinense and L. jeholense, which suggested these two genera are both in need of revision. This study offer valuable information for future research in the identification of Gaoben-related medicinal materials and will benefit for further phylogenetic study of Apiaceae.

New Pqs Quorum Sensing System Inhibitor as an Antibacterial Synergist against Multidrug-Resistant Pseudomonas aeruginosa.

Development of new bacterial biofilm inhibitors as antibacterial synergists is an effective strategy to solve the resistance of Pseudomonas aeruginosa. In this paper, a series of 3-hydroxy-pyridin-4(1H)-ones were synthesized and evaluated, and the hit compound (20p) was identified with the effects of inhibiting the production of pyocyanin (IC50 = 8.6 µM) and biofilm formation (IC50 = 4.5 µM). Mechanistic studies confirmed that 20p inhibits the formation of bacterial biofilm by inhibiting the expression of pqsA, blocking pqs quorum sensing system quinolone biosynthesis. Moreover, we systematically investigated the bactericidal effects of combining currently approved antibiotics for CF including tobramycin, ciprofloxacin, and colistin E with 20p, which showed obvious antibacterial synergy to overcome antibiotics resistance in multidrug-resistant P. aeruginosa biofilms. The result indicates that compound 20p may be used in the future as a potentially novel antibacterial synergist candidate for the treatment of P. aeruginosa infections.

Gestational arsenic exposure induces anxiety-like behaviors in adult offspring by reducing DNA hydroxymethylation in the developing brain.

Several studies found that reduction of 5-hydroxymethylcytosine (5hmC), a marker of DNA hydroxymethylation highly enriched in developing brain, is associated with anxiety-like behaviors. This study aimed to investigate whether gestational arsenic (As) exposure induces anxiety-like behaviors in adult offspring by reducing DNA hydroxymethylation in the developing brain. The dams drank ultrapure water containing NaAsO2 (15 mg/L) throughout pregnancy. Anxiety-like behaviors were evaluated and developing brain 5hmC was detected. Results showed that anxiety-like behaviors were observed in As-exposed adult offspring. In addition, 5hmC content was reduced in As-exposed fetal brain. Despite no difference on Tet1, Tet2 and Tet3 expression, TET activity was suppressed in As-exposed fetal brain. Mechanistically, alpha-ketoglutarate (α-KG), a cofactor for TET dioxygenases, was reduced and Idh2, a key enzymatic gene for mitochondrial α-KG synthesis, was downregulated in As-exposed fetal brain. Of interest, ascorbic acid, a cofactor for TET dioxygenases, reversed As-induced suppression of TET activity. Moreover, ascorbic acid attenuated As-induced reduction of 5hmC in fetal brain. In addition, ascorbic acid alleviated As-induced anxiety-like behaviors in adult offspring. Taken together, these results suggest that gestational As exposure induces anxiety-like behaviors in adult offspring, possibly at part, by inhibiting DNA hydroxymethylation in developing brain.

Paternal exposure to microcystin-LR induces fetal growth restriction partially through inhibiting cell proliferation and vascular development in placental labyrinth.

Microcystin-leucine arginine (MC-LR) has reproductive and developmental toxicities. Previous studies indicated that gestational exposure to MC-LR induced fetal growth restriction in mice. The aim of this study was to further evaluate the effect of paternal MC-LR exposure before mating on fetal development. Male mice were intraperitoneally injected with either normal saline or MC-LR (10 µg/kg) daily for 35 days. Male mouse was then mated with female mice with 1:1 ratio. There was no significant difference on the rates of mating and pregnancy between MC-LR-exposed male mice and controls. Body weight and crown-rump length were reduced in fetuses whose fathers were exposed to MC-LR. Despite no difference on relative thickness of labyrinthine layer, cell proliferation, as measured by Ki67 immunostaining, was reduced in labyrinth layer of MC-LR-exposed mice. Moreover, blood sinusoid area in labyrinth layer was decreased in the fetus whose father was exposed to MC-LR before mating. Correspondingly, cross-sectional area of CD34-positive blood vessel in labyrinth layer was lower in fetuses whose fathers were exposed to MC-LR than in controls. These results provide evidence that paternal MC-LR exposure before mating induces fetal growth restriction partially through inhibiting cell proliferation and vascular development in labyrinth layer.

Immunization with Aß3-10-KLH vaccine improves cognitive function and ameliorates mitochondrial dysfunction and reduces Alzheimer's disease-like pathology in Tg-APPswe/PSEN1dE9 mice.

Alzheimer's disease is a common cause of dementia, for which no disease-modifying therapy is yet available. Aß3-10-KLH, a vaccine for active immunization, has been shown to prevent pathological changes in young transgenic models of AD, but the effects of treatment with it and its effects on mitochondrial dysfunction remain unclear. We immunized 6-month-old Tg-APPswe/PSEN1dE9 mice with Aß3-10-KLH to analyze whether it is capable of eliminating amyloid-ß after its appearance. The vaccine effectively decreased amyloid-ß deposits, improved cognitive function and ameliorated mitochondrial dysfunction. These results indicate the potential of Aß3-10-KLH as a vaccine to treat AD.