Scavenging Reactive Lipids to Prevent Oxidative Injury.

Oxidative injury due to elevated levels of reactive oxygen species is implicated in cardiovascular diseases, Alzheimer's disease, lung and liver diseases, and many cancers. Antioxidant therapies have generally been ineffective at treating these diseases, potentially due to ineffective doses but also due to interference with critical host defense and signaling processes. Therefore, alternative strategies to prevent oxidative injury are needed. Elevated levels of reactive oxygen species induce lipid peroxidation, generating reactive lipid dicarbonyls. These lipid oxidation products may be the most salient mediators of oxidative injury, as they cause cellular and organ dysfunction by adducting to proteins, lipids, and DNA. Small-molecule compounds have been developed in the past decade to selectively and effectively scavenge these reactive lipid dicarbonyls. This review outlines evidence supporting the role of lipid dicarbonyls in disease pathogenesis, as well as preclinical data supporting the efficacy of novel dicarbonyl scavengers in treating or preventing disease.

Radiolabel Uncovers Nonintuitive Metabolites of BIIB104: Novel Release of [14C]Cyanide from 2-Cyanothiophene and Subsequent Formation of [14C]Thiocyanate.

BIIB104 (formerly PF-04958242), N-((3S,4S)-4-(4-(5-cyanothiophen-2-yl)phenoxy)tetrahydrofuran-3-yl)propane-2-sulfonamide, is an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor potentiator investigated for the treatment of cognitive impairment associated with schizophrenia. Preliminary in vitro metabolism studies with non-radiolabeled BIIB104 in rat, dog, and human liver microsomes (RLM, DLM, and HLM) showed O-dealkylation in all three species, tetrahydrofuran hydroxylation dominating in DLM and HLM, and thiophene hydroxylation prevalent in RLM. However, a subsequent rat mass balance study with [nitrile-14C]BIIB104 showed incomplete recovery of administered radioactivity (∼80%) from urine and feces over 7 days following an oral dose, and an exceptionally long plasma total radioactivity half-life. Radiochromatographic metabolite profiling and identification, including chemical derivation, revealed that [14C]cyanide was a major metabolite of [nitrile-14C]BIIB104 in RLM, but a minor and trace metabolite in DLM and HLM, respectively. Correspondingly in bile duct-cannulated rats, [14C]thiocyanate accounted for ∼53% of total radioactivity excreted over 48 hours postdose and it, as an endogenous substance, explained the exceptionally long plasma radioactivity half-life. The release of [14C]cyanide from the 2-cyanothiophene moiety is postulated to follow an epoxidation-initiated thiophene-opening based on the detection of non-radiolabeled counterpart metabolites in RLM. This unusual biotransformation serves as a lesson regarding placement of the radioactive label on an aryl nitrile when material will be used for evaluating the metabolism of a new drug candidate. Additionally, the potential cyanide metabolite of nitrile-containing drug molecules may be detected in liver microsomes with liquid chromatography-mass spectrometry following a chemical derivatization. SIGNIFICANCE STATEMENT: Using [nitrile-14C]BIIB104, non-intuitive metabolites of BIIB104 were discovered involving a novel cyanide release from the 2-cyanothiophene motif via a postulated epoxidation-initiated thiophene-opening. This unusual biotransformation serves as a lesson regarding placement of the radioactive label on an aryl nitrile when material will be used for evaluating the metabolism of a new drug candidate.

SR-BI as a target of natural products and its significance in cancer.

Scavenger receptor class B type I (SR-BI) protein is an integral membrane glycoprotein. SR-BI is emerging as a multifunctional protein, which regulates autophagy, efferocytosis, cell survival and inflammation. It is well known that SR-BI plays a critical role in lipoprotein metabolism by mediating cholesteryl esters selective uptake and the bi-directional flux of free cholesterol. Recently, SR-BI has also been identified as a potential marker for cancer diagnosis, prognosis, or even a treatment target. Natural products are a promising source for the discovery of new drug leads. Multiple natural products were identified to regulate SR-BI protein expression. There are still a number of challenges in modulating SR-BI expression in cancer and in using natural products for modulation of such protein expression. In this review, our purpose is to discuss the relationship between SR-BI protein and cancer, and the molecular mechanisms regulating SR-BI expression, as well as to provide an overview of natural products that regulate SR-BI expression.

Mediator subunit MED1 deficiency prevents carbon tetrachloride-induced hepatic fibrosis in mice.

Mediator subunit mediator 1 (MED1) mediates ligand-dependent binding of the mediator coactivator complex to various nuclear receptors and plays a critical role in embryonic development, lipid and glucose metabolism, liver regeneration, and tumorigenesis. However, the precise role of MED1 in the development of liver fibrosis has been unclear. Here, we showed that MED1 expression was increased in livers from nonalcoholic steatohepatitis (NASH) patients and mice and positively correlated with transforming growth factor ß (TGF-ß) signaling and profibrotic factors. Upon treatment with carbon tetrachloride (CCl4), hepatic fibrosis was much less in liver-specific MED1 deletion (MED1ΔLiv) mice than in MED1fl/fl littermates. TGF-ß/Smad2/3 signaling pathway was inhibited, and gene expression of fibrotic markers, including α-smooth muscle actin (α-SMA), collagen type 1 α 1 (Col1a1), matrix metalloproteinase-2 (Mmp2), and metallopeptidase inhibitor 1 (Timp1) were decreased in livers of MED1ΔLiv mice with CCl4 injection. Transcriptomic analysis revealed that the differentially expressed genes in livers of CCl4-administered MED1ΔLiv mice were enriched in the pathway of oxidoreductase activity, followed by robustly reduced oxidoreductase activity-related genes, such as Gm4756, Txnrd3, and Etfbkmt. More importantly, we found that the reduction of reactive oxygen species (ROS) in MED1 knockdown hepatocytes blocked the activation of TGF-ß/Smad2/3 pathway and the expression of fibrotic genes in LX2 cells. These results indicate that MED1 is a positive regulator for hepatic fibrogenesis, and MED1 may be considered as a potential therapeutic target for the regression of liver fibrosis.NEW & NOTEWORTHY In this study, we present the first evidence that liver mediator 1 (MED1) deficiency attenuated carbon tetrachloride-induced hepatic fibrosis in mouse. The underlying mechanism is that MED1 deficiency reduces reactive oxygen species (ROS) production in hepatocytes, thus restricts the activation of TGF-ß/Smad2/3 signaling pathway and fibrogenic genes expression in hepatic stellate cells (HSCs). These data suggest that MED1 is an essential regulator for hepatic fibrogenesis, and MED1 may be considered as a potential therapeutic target for liver fibrosis.

Regulation of PGC1α Downstream of the Insulin Signaling Pathway Plays a Role in the Hepatic Proteotoxicity of Mutant α1-Antitrypsin Deficiency Variant Z.

BACKGROUND & AIMS: Insulin signaling is known to regulate essential proteostasis mechanisms. METHODS: The analyses here examined effects of insulin signaling in the PiZ mouse model of α1-antitrypsin deficiency in which hepatocellular accumulation and proteotoxicity of the misfolded α1-antitrypsin Z variant (ATZ) causes liver fibrosis and cancer. RESULTS: We first studied the effects of breeding PiZ mice to liver-insulin-receptor knockout (LIRKO) mice (with hepatocyte-specific insulin-receptor gene disruption). The results showed decreased hepatic ATZ accumulation and liver fibrosis in PiZ x LIRKO vs PiZ mice, with reversal of those effects when we bred PiZ x LIRKO mice onto a FOXO1-deficient background. Increased intracellular degradation of ATZ mediated by autophagy was identified as the likely mechanism for diminished hepatic proteotoxicity in PiZ x LIRKO mice and the converse was responsible for enhanced toxicity in PiZ x LIRKO x FOXO1-KO animals. Transcriptomic studies showed major effects on oxidative phosphorylation and autophagy genes, and significant induction of peroxisome proliferator-activated-receptor-γ-coactivator-1α (PGC1α) expression in PiZ-LIRKO mice. Because PGC1α plays a key role in oxidative phosphorylation, we further investigated its effects on ATZ proteostasis in our ATZ-expressing mammalian cell model. The results showed PGC1α overexpression or activation enhances autophagic ATZ degradation. CONCLUSIONS: These data implicate suppression of autophagic ATZ degradation by down-regulation of PGC1α as one mechanism by which insulin signaling exacerbates hepatic proteotoxicity in PiZ mice, and identify PGC1α as a novel target for development of new human α1-antitrypsin deficiency liver disease therapies.

Safety and Immunogenicity of SARS-CoV-2 Vaccines in Patients With Chronic Liver Diseases (CHESS-NMCID 2101): A Multicenter Study.

BACKGROUND & AIMS: We aimed to assess the safety and immunogenicity of inactivated whole-virion severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in patients with chronic liver diseases (CLD) in this study. METHODS: This was a prospective, multi-center, open-label study. Participants aged over 18 years with confirmed CLD and healthy volunteers were enrolled. All participants received 2 doses of inactivated whole-virion SARS-CoV-2 vaccines. Adverse reactions were recorded within 14 days after any dose of SARS-CoV-2 vaccine, laboratory testing results were collected after the second dose, and serum samples of enrolled subjects were collected and tested for SARS-CoV-2 neutralizing antibodies at least 14 days after the second dose. RESULTS: A total of 581 participants (437 patients with CLD and 144 healthy volunteers) were enrolled from 15 sites in China. Most adverse reactions were mild and transient, and injection site pain (n = 36; 8.2%) was the most frequently reported adverse event. Three participants had grade 3 aminopherase elevation (defined as alanine aminopherase >5 upper limits of normal) after the second dose of inactivated whole-virion SARS-CoV-2 vaccination, and only 1 of them was judged as severe adverse event potentially related to SARS-CoV-2 vaccination. The positive rates of SARS-CoV-2 neutralizing antibodies were 76.8% in the noncirrhotic CLD group, 78.9% in the compensated cirrhotic group, 76.7% in the decompensated cirrhotic group (P = .894 among CLD subgroups), and 90.3% in healthy controls (P = .008 vs CLD group). CONCLUSION: Inactivated whole-virion SARS-CoV-2 vaccines are safe in patients with CLD. Patients with CLD had lower immunologic response to SARS-CoV-2 vaccines than healthy population. The immunogenicity is similarly low in noncirrhotic CLD, compensated cirrhosis, and decompensated cirrhosis.

Safety and immunogenicity of COVID-19 vaccination in patients with hepatocellular carcinoma (CHESS-NMCID 2101): A multicenter prospective study.

Data on safety and immunogenicity of coronavirus disease 2019 (COVID-19) vaccinations in hepatocellular carcinoma (HCC) patients are limited. In this multicenter prospective study, HCC patients received two doses of inactivated whole-virion COVID-19 vaccines. The safety and neutralizing antibody were monitored. Totally, 74 patients were enrolled from 10 centers in China, and 37 (50.0%), 25 (33.8%), and 12 (16.2%) received the CoronaVac, BBIBP-CorV, and WIBP-CorV, respectively. The vaccines were well tolerated, where pain at the injection site (6.8% [5/74]) and anorexia (2.7% [2/74]) were the most frequent local and systemic adverse events. The median level of neutralizing antibody was 13.5 (interquartile range [IQR]: 6.9-23.2) AU/ml at 45 (IQR: 19-72) days after the second dose of vaccinations, and 60.8% (45/74) of patients had positive neutralizing antibody. Additionally, lower γ-glutamyl transpeptidase level was related to positive neutralizing antibody (odds ratio = 1.022 [1.003-1.049], p = 0.049). In conclusion, this study found that inactivated COVID-19 vaccinations are safe and the immunogenicity is acceptable or hyporesponsive in patients with HCC. Given that the potential benefits may outweigh the risks and the continuing emergences of novel severe acute respiratory syndrome coronavirus 2 variants, we suggest HCC patients to be vaccinated against COVID-19. Future validation studies are warranted.

Optimization of a novel piperazinone series as potent selective peripheral covalent BTK inhibitors.

BTK is a tyrosine kinase playing an important role in B cell and myeloid cell functions through B cell receptor (BCR) signaling and Fc receptor (FcR) signaling. Selective inhibition of BTK has the potential to provide therapeutical benefits to patients suffering from autoimmune diseases. Here we report the design, optimization, and characterization of novel potent and highly selective covalent BTK inhibitors. Starting from a piperazinone hit derived from a selective reversible inhibitor, we solved the whole blood cellular potency issue by introducing an electrophilic warhead to reach Cys481. This design led to a covalent irreversible BTK inhibitor series with excellent kinase selectivity as well as good whole blood CD69 cellular potency. Optimization of metabolic stability led to representative compounds like 42, which demonstrated strong cellular target occupancy and inhibition of B-cell proliferation measured by proximal and distal functional activity.

Optimal pH 8.5 to 9 for the hydrolysis of vixotrigine and other basic substrates of carboxylesterase-1 in human liver microsomes.

Vixotrigine is a voltage- and use-dependent sodium channel blocker under investigation for the potential treatment of neuropathic pain. One of the major in vivo metabolic pathways of vixotrigine in humans is the hydrolysis of the carboxamide to form the carboxylic acid metabolite M14.The in vitro formation of M14 in human hepatocytes was inhibited by the carboxylesterase (CES) inhibitor Bis(4-nitrophenyl) phosphate in a concentration-dependent manner. The hydrolysis reaction was identified to be catalysed by recombinant human CES1b.Initial observation of only trace level formation of M14 in human liver microsomes at pH 7.4 caused us to doubt the involvement of CES1, an enzyme localised at the endoplasmic reticulum and the dominant carboxylesterase in human liver. Further investigation has revealed that optimal pH for the hydrolysis of vixotrigine and two other basic substrates of CES1, methylphenidate and oseltamivir, in human liver microsomes was pH 8.5-9 which is higher than their respective pKa(base), suggesting that neutral form of basic substrates is probably preferred for CES1 catalysis in liver microsomes.

Characterization of a Novel Carbapenem-Resistant Klebsiella michiganensis Strain Coharboring the blaSIM-1, blaOXA-1, blaCTX-M-14, qnrS, and aac(6')-Ib-cr Genes.

Carbapenem-resistant Klebsiella michiganensis (CRKM) and Klebsiella oxytoca (CRKO) strains have occasionally been reported to cause severe infections. However, SIM-producing K. michiganensis strains have never been described. In this study, we phenotypically and genetically characterized 6 CRKM and CRKO strains isolated over the past 10 years at a Chinese tertiary hospital. All six strains were positive for the mCIM test, and five were positive for the MBL test. Carbapenemase-encoding genes (blaKPC, blaNDM, blaVIM, blaIMP, blaOXA-23, blaOXA-24, blaOXA-51, and blaOXA-58) and another 12 resistance genes were screened by PCR, and blaKPC, blaNDM, and blaIMP were identified in five strains. However, the CRKM strain KM41, which was resistant to IPM and MEM with minimum inhibitory concentrations (MICs) of 4 µg/ml and 16 µg/ml, respectively, had positive mCIM and MBL results but lacked the eight carbapenemase-encoding genes. Whole-genome sequencing of the KM41 strain revealed more than 20 drug resistance genes; in particular, blaSIM-1, blaOXA-1, blaCTX-M-14, qnrS, aac(6')-Ib-cr, aadA17, and aar-3 were found to be located in a single plasmid. To the best of our knowledge, this is the first description of a K. michiganensis strain coharboring blaSIM-1, blaOXA-1, blaCTX-M-14, qnrS, and aac(6')-Ib-cr in China.

Kidney injury-mediated disruption of intestinal lymphatics involves dicarbonyl-modified lipoproteins.

Kidney disease affects intestinal structure and function. Although intestinal lymphatics are central in absorption and remodeling of dietary and synthesized lipids/lipoproteins, little is known about how kidney injury impacts the intestinal lymphatic network, or lipoproteins transported therein. To study this, we used puromycin aminoglycoside-treated rats and NEP25 transgenic mice to show that proteinuric injury expanded the intestinal lymphatic network, activated lymphatic endothelial cells and increased mesenteric lymph flow. The lymph was found to contain increased levels of cytokines, immune cells, and isolevuglandin (a highly reactive dicarbonyl) and to have a greater output of apolipoprotein AI. Plasma levels of cytokines and isolevuglandin were not changed. However, isolevuglandin was also increased in the ileum of proteinuric animals, and intestinal epithelial cells exposed to myeloperoxidase produced more isolevuglandin. Apolipoprotein AI modified by isolevuglandin directly increased lymphatic vessel contractions, activated lymphatic endothelial cells, and enhanced the secretion of the lymphangiogenic promoter vascular endothelial growth factor-C by macrophages. Inhibition of isolevuglandin synthesis by a carbonyl scavenger reduced intestinal isolevuglandin adduct level and lymphangiogenesis. Thus, our data reveal a novel mediator, isolevuglandin modified apolipoprotein AI, and uncover intestinal lymphatic network structure and activity as a new pathway in the crosstalk between kidney and intestine that may contribute to the adverse impact of kidney disease on other organs.

Identification and characteristics of a novel aminoglycoside phosphotransferase, APH(3')-IId, from an MDR clinical isolate of Brucella intermedia.

OBJECTIVES: To describe a novel chromosomal aminoglycoside phosphotransferase named APH(3')-IId identified in an MDR Brucella intermedia ZJ499 isolate from a cancer patient. METHODS: Species identity was determined by PCR and MALDI-TOF MS analysis. WGS was performed to determine the genetic elements conferring antimicrobial resistance. Gene cloning, transcriptional analysis and targeted gene deletion, as well as protein purification and kinetic analysis, were performed to investigate the mechanism of resistance. RESULTS: APH(3')-IId consists of 266 amino acids and shares the highest identity (48.25%) with the previously known APH(3')-IIb. Expression of aph(3')-IId in Escherichia coli decreased susceptibility to kanamycin, neomycin, paromomycin and ribostamycin. The aph(3')-IId gene in ZJ499 was transcriptionally active under laboratory conditions and the relative abundance of this transcript was unaffected by treatment with the above four antibiotics. However, deletion of aph(3')-IId in ZJ499 results in decreased MICs of these drugs. The purified APH(3')-IId showed phosphotransferase activity against kanamycin, neomycin, paromomycin and ribostamycin, with catalytic efficiencies (kcat/Km) ranging from ∼105 to 107 M-1 s-1. Genetic environment and comparative genomic analyses suggested that aph(3')-IId is probably a ubiquitous gene in Brucella, with no mobile genetic elements detected in its surrounding region. CONCLUSIONS: APH(3')-IId is a novel chromosomal aminoglycoside phosphotransferase and plays an important role in the resistance of B. intermedia ZJ499 to kanamycin, neomycin, paromomycin and ribostamycin. To the best of our knowledge, APH(3')-IId represents the fourth characterized example of an APH(3')-II enzyme.

Lymphocyte subset alterations with disease severity, imaging manifestation, and delayed hospitalization in COVID-19 patients.

BACKGROUND: COVID-19 continuously threated public health heavily. Present study aimed to investigate the lymphocyte subset alterations with disease severity, imaging manifestation, and delayed hospitalization in COVID-19 patients. METHODS: Lymphocyte subsets was classified using flow cytometry with peripheral blood collected from 106 patients. RESULTS: Multivariate logistic regression showed that chest tightness, lymphocyte count, and γ-glutamyl transpeptidase were the independent predictors for severe COVID-19. The T cell, CD4+ T cell and B cell counts in severe patients were significantly lower than that in mild patients (p = 0.004, 0.003 and 0.046, respectively). Only the T cell count was gradually decreased with the increase of infiltrated quadrants of lesions in computed tomography (CT) (p = 0.043). The T cell, CD4+ T cell, and CD8+ T cell counts were gradually decreased with the increase of infiltrated area of the maximum lesion in CT (p = 0.002, 0.003, 0.028; respectively). For severe patients, the counts of T cell, CD4+ T cell, CD8+ T cell gradually decreased with the increased delayed hospitalization (p = 0.001, 0.03, and <  0.001, respectively). The proportions of T cell, CD8+ T cell gradually decreased with the increased delayed hospitalization (both p <  0.001), but the proportions of NK cell, B cell gradually increased with the increased delayed hospitalization (p = 0.007, and 0.002, respectively). For mild patients, only the NK cell count was gradually decreased with the increased delayed hospitalization (p = 0.012). CONCLUSION: T lymphocyte and its subset negatively correlated with disease severity, CT manifestation and delayed hospitalization. The counts of lymphocyte subset were changed more profound than their proportions.

Cloning of Mn-SOD gene and its mRNA expression difference and antioxidant enzyme activities under hypoxia stress of cobia Rachycentron canadum.

BACKGROUND: Environmental hypoxia affects the survival and development of organisms. It is also an important environmental factor that leads to oxidative damage. Hypoxia is a condition in which tissues are deprived of oxygen; reoxygenation is the phenomenon in which hypoxic tissues are exposed to oxygen. Hypoxia-reoxygenation is vital in pathogenesis, where the production of reactive oxygen species and antioxidant disparity significantly contribute to disease progression, and it is one of the most common physiological stressors in the aquaculture industry. METHODS AND RESULTS: In this study, the full length of complementary DNA (cDNA) of the manganese superoxide dismutase (Mn-SOD) gene of healthy cobia Rachycentron canadum was analysed using rapid amplification of cDNA ends. The real-time quantitative Polymerase Chain Reaction was used to measure the expression levels of Mn-SOD mRNAs in various tissues (heart, muscle, brain, liver, kidney, gill, intestine, and spleen). The 2-ΔΔCT method was used to performed the expression analysis. The experimental data were analysed using SPSS ver. 19.0 ( https://spss.software.informer.com/19.0/ ). P < 0.05 and P < 0.01 were set as significant differences. The values were articulated as mean ± standard deviation. The Mn-SOD gene cDNA sequence was 1209 bp long, including a 684 bp open reading frame, 42 bp 5'UTR and 483 bp 3'UTR, encoding 227 amino acids. Under hypoxia-reoxygen stress, the expression of Mn-SOD in brain tissue was significantly lower than in the control group after 8 h of reoxygenation and higher than the control group after 24 h. Hypoxia and subsequent reoxygenation triggered a disturbance in antioxidant homeostasis, displayed in the modification of GPx expression/activity in the liver: GPx was improved. CONCLUSIONS: These results provide valuable information on the role of Mn-SOD regulation in oxidative stress caused by hypoxia.

Characteristics of expanded polystyrene microplastics on island beaches in the Pearl River Estuary: abundance, size, surface texture and their metals-carrying capacity.

While expanded polystyrene (EPS) microplastics have been widely recognized as one of the most important components of plastic litter in the intertidal zones of the global ocean, our understanding of their environmental fate on island beaches is insufficient. In this study, we intended to reveal that the latest EPS microplastic pollution status on 5 island beaches in the Pearl River Estuary, China, by comprehensively assessing the abundance, distribution, size, surface texture and carrying capacity of heavy metals (Cd, As, Cr, Ni, Cu, Pb, Mn, Fe, Al). High level of EPS microplastic abundance ranged from 328 to 82,276 particles m-2 was found, with the highest abundance at Guishan Island and the lowest at Dong'ao Island. Spatial distribution of EPS microplastic abundance was significantly different among different islands. EPS microplastics in the size range of 1-2 mm were the most abundant. The content of heavy metals in EPS microplastics collected on the beaches was greater than that in the new EPS products. The average concentrations of heavy metals in EPS microplastics from 5 islands are Cd (0.27 ± 0.19 µg g-1), As (5.50 ± 3.84 µg g-1), Cr (14.9 ± 8.25 µg g-1), Cu (15.0 ± 7.66 µg g-1), Ni (17.2 ± 17.6 µg g-1), Pb (24.8 ± 7.39 µg g-1), Mn (730 ± 797 µg g-1), Fe (8340 ± 4760 µg g-1), and Al (9624 ± 6187 µg g-1), respectively. The correlation between heavy metals in EPS microplastics and sediments was better than that between heavy metals in EPS microplastics and seawater. The study results indicated that EPS microplastics could act as a carrier for the transport of heavy metals, which might pose a threat to biological and human health.

Identification and expression analysis of cobia (Rachycentron canadum) liver-related miRNAs under hypoxia stress.

At present, due to the influence of global warming, seasonal change, diurnal variation, and eutrophication of the water body, hypoxia has become one of the major factors limiting the stable development of cobia (Rachycentron canadum) culture. In this study, the miRNAs involved in hypoxia stress were screened, and the target genes of miRNAs were annotated and analyzed. The results showed that a total of 184 conservative microRNA (miRNA) and 121 newly predicted miRNA were obtained by sequencing the liver of control (C) and hypoxic (dissolved oxygen, DO (2.64 ± 0.25) mg/L; 3 h) (S) groups. The pathways involved in energy metabolism included starch and sucrose metabolism (ko00500), glycosaminoglycan degradation (ko00531), and galactose metabolism (ko00052). The results indicate that the body maintains physiological activities by regulating some important pathways at the transcriptional level under hypoxia stress, such as the conversion of aerobic metabolism and anaerobic metabolism, the reduction of energy consumption, and the promotion of red blood cell proliferation to maintain the homeostasis of the body.

Genetic Factors Associated with Enhanced blaKPC Expression in Tn3/Tn4401 Chimeras.

The expression of the blaKPC gene plays a key role in carbapenem resistance in Enterobacteriaceae However, the genetic regulators of the blaKPC gene have not been completely elucidated, especially the genes in Tn3-Tn4401 chimeras. Two novel Tn3-Tn4401 chimera isoforms were characterized in our hospital, isoform A (CTA), which harbors a 121-bp deletion containing the PX promoter and was present in 22.6% (54/239) of isolates, and isoform C (CTC), which harbors a 624-bp insertion and a P1 promoter deletion and was present in only 1 isolate. The carbapenem MICs of both isoforms were 2-fold or more higher than those of the wild type (Tn3-Tn4401 chimera, CTB), and blaKPC was most highly expressed in CTA. Bioinformatics and 5' rapid amplification of cDNA ends (5' RACE) experiments indicated a novel strong putative promoter, PY, at the 3' end of the ISKpn8 gene. PY mutation nearly abrogated blaKPC expression (P < 0.01) and restored carbapenem susceptibility in all 3 isoforms. Although the mutation of PX or P1 halved blaKPC expression in CTB (P < 0.05), PX deletion caused a 68% increase in blaKPC expression (P = 0.037) in CTA. The level of blaKPC mRNA in CTC was 8-fold higher than that in InCTC, which harbors P1 (P = 0.011). These results suggest that PY is a core promoter of the blaKPC gene in the chimeras and that the deletion of the PX and P1 promoters enhanced gene expression in CTA and CTC, respectively.

Profiling the urinary microbiome in men with calcium-based kidney stones.

BACKGROUND: The dogma that urine is sterile in healthy individuals has been overturned by recent studies applying molecular-based methods. Mounting evidences indicate that dysbiosis of the urinary microbiota is associated with several urological diseases. In this study, we aimed to investigate the urinary microbiome of male patients with calcium-based kidney stones and compare it with those of healthy individuals. RESULTS: The diversity of the urinary microbiota in kidney stone patients was significantly lower than that of healthy controls based on the Shannon and Simpson index (P < 0.001 for both indices). The urinary microbiota structure also significantly differed between kidney stone patients and healthy controls (ANOSIM, R = 0.11, P < 0.001). Differential representation of inflammation associated bacteria (e.g., Acinetobacter) and several enriched functional pathways were identified in the urine of kidney stones patients. Meanwhile, we found the species diversity, overall composition of microbiota and predicted functional pathways were similar between bladder urine and renal pelvis urine in kidney stone patients. CONCLUSIONS: A marked dysbiosis of urinary microbiota in male patients with calcium-based kidney stones was observed, which may be helpful to interpret the association between bacteria and calcium-based kidney stones.

Roles of Reconstituted High-Density Lipoprotein Nanoparticles in Cardiovascular Disease: A New Paradigm for Drug Discovery.

Epidemiological results revealed that there is an inverse correlation between high-density lipoprotein (HDL) cholesterol levels and risks of atherosclerotic cardiovascular disease (ASCVD). Mounting evidence supports that HDLs are atheroprotective, therefore, many therapeutic approaches have been developed to increase HDL cholesterol (HDL-C) levels. Nevertheless, HDL-raising therapies, such as cholesteryl ester transfer protein (CETP) inhibitors, failed to ameliorate cardiovascular outcomes in clinical trials, thereby casting doubt on the treatment of cardiovascular disease (CVD) by increasing HDL-C levels. Therefore, HDL-targeted interventional studies were shifted to increasing the number of HDL particles capable of promoting ATP-binding cassette transporter A1 (ABCA1)-mediated cholesterol efflux. One such approach was the development of reconstituted HDL (rHDL) particles that promote ABCA1-mediated cholesterol efflux from lipid-enriched macrophages. Here, we explore the manipulation of rHDL nanoparticles as a strategy for the treatment of CVD. In addition, we discuss technological capabilities and the challenge of relating preclinical in vivo mice research to clinical studies. Finally, by drawing lessons from developing rHDL nanoparticles, we also incorporate the viabilities and advantages of the development of a molecular imaging probe with HDL nanoparticles when applied to ASCVD, as well as gaps in technology and knowledge required for putting the HDL-targeted therapeutics into full gear.

RNA-seq analysis reveals divergent adaptive response to hyper- and hypo-salinity in cobia, Rachycentron canadum.

Salinity is an important abiotic stress that affects metabolic and physiological activities, breed, development, and growth of marine fish. Studies have shown that cobia (Rachycentron canadum), a euryhaline marine teleost fish, possesses the ability of rapid and effective hyper/hypo iono- and osmoregulation. However, genomic studies on this species are lacking and it has not been studied at the transcriptome level to identify the genes responsible for salinity regulation, which affects the understanding of the fundamental mechanism underlying adaptation to fluctuations in salinity. To describe the molecular response of cobia to different salinity levels, we used RNA-seq analysis to identify genes and biological processes involved in response to salinity changes. In the present study, 395,080,114 clean reads were generated and then assembled into 65,318 unigenes with an N50 size of 2758 bp. There were 20,671 significantly differentially expressed genes (DEGs) including 8805 genes adapted to hypo-salinity and 11,866 genes adapted to hyper-salinity. These DEGs were highly represented in steroid biosynthesis, unsaturated fatty acid metabolism, glutathione metabolism, energy metabolism, osmoregulation, and immune response. The candidate genes identified in cobia provide valuable information for studying the molecular mechanism of salinity adaptation in marine fish. Furthermore, the transcriptomic sequencing data acts not only as an important resource for the identification of novel genes but also for further investigations regarding cobia biology.