Lactate administration improves laboratory parameters in murine models of iron overload.

ABSTRACT: Current iron overload therapeutics have inherent drawbacks including perpetuated low hepcidin. Here, we unveiled that lactate, a potent hepcidin agonist, effectively reduced serum and hepatic iron levels in mouse models of iron overload with an improved erythropoiesis in ß-thalassemic mice.

Effect of governor vessel moxibustion (GVM) therapy with mild to moderate psoriasis: A randomized clinical trial.

BACKGROUND: It was hypothesized that governor vessel moxibustion (GVM) therapy may improve the course of mild to moderate psoriasis (PS) in patients. METHODS: A randomized, controlled clinical trial lasting 40 days was conducted at the Shaanxi Provincial Hospital of Chinese Medicine. Investigators were blinded to patient groupings. Individuals with mild to moderate PS ranging in age from 18 to 70 years were enrolled. GVM therapy was administered one every 10 days for 40 days with 1.5 hours on the governor meridian in the GVM therapy group. The PS area and severity index (PASI) and dermatological life quality index (DLQI) scores were monitored before and after treatment. RESULTS: There was a significant reduction in the mean PASI score in the GVM therapy group of 0.76 points (2.37 [2.61]; SE, 0.39) after 40 days of treatment compared with the control group (3.12 [2.12], SE, 0.32) (P < .01). There were also significantly greater changes in the DLQI scores of the GVM therapy group (4.23 [2.25]; SE, 0.34) compared with those in the control group (8.91 [3.85]; SE, 0.59) (P < .001). CONCLUSION: GVM therapy effectively reduced both PASI and DLQI scores in patients with mild to moderate PS.

Lactate modulates iron metabolism by binding soluble adenylyl cyclase.

Overproduction of lactate (LA) can occur during exercise and in many diseases such as cancers. Individuals with hyperlactatemia often display anemia, decreased serum iron, and elevated hepcidin, a key regulator of iron metabolism. However, it is unknown whether and how LA regulates hepcidin expression. Here, we show LA binds to soluble adenylyl cyclase (sAC) in normal hepatocytes and affects systemic iron homeostasis in mice by increasing hepcidin expression. Comprehensive in vitro, in vivo, and in silico experiments show that the LA-sAC interaction raises cyclic adenosine monophosphate (cAMP) levels, which activates the PKA-Smad1/5/8 signaling pathway to increase hepcidin transcription. We verified this regulatory axis in wild-type mice and in mice with disordered iron homeostasis. LA also regulates hepcidin in humans at rest and subjected to extensive exercise that produce elevated LA. Our study links hyperlactatemia to iron deficiency, offering a mechanistic explanation for anemias seen in athletes and patients with lactic acidosis.

Clinical characteristics of central nervous system candidiasis due to Candida albicans in children: a single-center experience.

BACKGROUND: Central nervous system candidiasis due to Candida albicans (CNSC) in children is easily misdiagnosed and is associated with poor outcomes and a high mortality rate. There is no big data research or systematic review of CNSC. METHODS: Patients diagnosed as CNSC with positive culture results of Candida albicans in Beijing Children's Hospital affiliated to Capital Medical University from March 2010 to March 2019 were included. Patients receiving immunosuppressive therapy or transplantation, or with malignant tumours were excluded. We analysed the clinical characteristics, follow-up results, drug susceptibility tests and whole-exome sequencing (WES) results. RESULTS: Thirty-three definitive patients were enrolled, including 22 males and 11 females. Twenty-five patients suffered from CNSC when they were less than 1 year old, and a total of 29 patients had high-risk factors. The main clinical manifestations were fever, convulsions, and positive neurological signs. Twenty-two patients had CNS infections alone, and 11 patients had CNS infections combined with invasive infections involving multiple sites. Twenty-seven cases had a positive CSF and/or blood culture at our hospital. All strains were susceptible to fluconazole, and 2 strains had intermediate susceptibility to voriconazole. As for amphotericin B, all the strains were wild type (WT). WES of 16 patients revealed 2 cases with CARD9 mutations, who suffered from recurrent onychomycosis or thrush before. CONCLUSION: CNSC mostly existed in children younger than 1 year old, who all had underlying risk factors. CNSC patients with onset at an older age or with recurrent superficial fungal infections might have primary immunodeficiency.

High-throughput sequencing unravels the cell heterogeneity of cerebrospinal fluid in the bacterial meningitis of children.

Bacterial meningitis (BM) is a common life-threatening infection in children that occurs in the central nervous system (CNS). The cytologic examination of cerebrospinal fluid (CSF) is a key parameter in the diagnosis of BM, but the heterogeneity of cells in the CSF has not been elucidated, which limits the current understanding of BM neuroinflammation. In this study, CSF samples were collected from a number of BM patients who were in different stages of disease progression. Single-cell RNA-sequencing (scRNA-seq), with additional bulk transcriptome sequencing, was conducted to decipher the characteristics of CSF cells in BM progression. A total of 18 immune cell clusters in CSF were identified, including two neutrophils, two monocytes, one macrophage, four myeloid dendritic cells, five T cells, one natural killer cell, one B cell, one plasmacytoid dendritic cell, and one plasma cell subtype. Their population profiles and dynamics in the initial onset, remission, and recovery stages during BM progression were also characterized, which showed decreased proportions of myeloid cells and increased proportions of lymphoid cells with disease progression. One novel neutrophil subtype, FFAR2+TNFAIP6+ neutrophils, and one novel monocyte subtype, THBS1+IL1B+ monocytes, were discovered, and their quantity changes positively correlated with the intensity of the inflammatory response in the CSF during BM. In addition, the CSF of BM patients with unsatisfactory therapeutic responses presented with different cell heterogeneity compared to the CSF of BM patients with satisfactory therapeutic responses, and their CSF featured altered intercellular communications and increased proportions of type II myeloid dendritic cells and plasmacytoid dendritic cells. Moreover, the bulk transcriptome profiles of autologous CSF cells and peripheral blood leukocytes of BM patients showed that the immune cells in these two physiological compartments exhibited distinct immune responses under different onset conditions. In particular, the CSF cells showed a high expression of macrophage characteristic genes and a low expression of platelet characteristic genes compared with peripheral blood leukocytes. Our study conducted an in-depth exploration of the characteristics of CSF cells in BM progression, which provided novel insights into immune cell engagement in acute CNS infection.

New Deferric Amine Compounds Efficiently Chelate Excess Iron to Treat Iron Overload Disorders and to Prevent Ferroptosis.

Excess iron accumulation occurs in organs of patients with certain genetic disorders or after repeated transfusions. No physiological mechanism is available to excrete excess iron and iron overload to promote lipid peroxidation to induce ferroptosis, thus iron chelation becomes critical for preventing ion toxicity in these patients. To date, several iron chelators have been approved for iron chelation therapy, such as deferiprone and deferoxamine, but the current iron chelators suffer from significant limitations. In this context, new agents are continuously sought. Here, a library of new deferric amine compounds (DFAs) with adjustable skeleton and flexibility is synthesized by adopting the beneficial properties of conventional chelators. After careful evaluations, compound DFA1 is found to have greater efficacy in binding iron through two molecular oxygens in the phenolic hydroxyl group and the nitrogen atom in the amine with a 2:1 stoichiometry. This compound remarkably ameliorates iron overload in diverse murine models through both oral and intravenous administration, including hemochromatosis, high iron diet-induced, and iron dextran-stimulated iron accumulation. Strikingly, this compound is found to suppress iron-induced ferroptosis by modulating the intracellular signaling that drives lipid peroxidation. This study opens a new approach for the development of iron chelators to treat iron overload.

Talaromynoids A-E: Five New Fusicoccane Diterpenoids from the Endophytic Fungus Talaromyces sp. DC-26.

Talaromynoids A-E (1-5), five new fusicoccane diterpenoids, were obtained from the endophytic fungus Talaromyces sp. DC-26, which was isolated from a wild leech. Talaromynoid A (1) represents the first fusicoccane diterpenoid bearing an unexpected 5-7-5 tricyclic ring system, which is possibly derived from normal 5-8-5 ones by ring contraction. Talaromynoid E (5) is characterized by an unusual oxygen bridge between C-1 and C-8 that establishes the eight-membered ring B to be a 9-oxo-bicyclo[3.3.1]nonane. Structures of 1-5 with absolute configurations were determined by extensive NMR spectral analyses, electronic circular dichroism (ECD) calculations, X-ray diffraction analyses, and acid hydrolysis.

m6A demethylation of cytidine deaminase APOBEC3B mRNA orchestrates arsenic-induced mutagenesis.

The cytidine deaminase APOBEC3B (A3B) is an endogenous inducer of somatic mutations and causes chromosomal instability by converting cytosine to uracil in single-stranded DNA. Therefore, identification of factors and mechanisms that mediate A3B expression will be helpful for developing therapeutic approaches to decrease DNA mutagenesis. Arsenic (As) is one well-known mutagen and carcinogen, but the mechanisms by which it induces mutations have not been fully elucidated. Herein, we show that A3B is upregulated and required for As-induced DNA damage and mutagenesis. We found that As treatment causes a decrease of N6-methyladenosine (m6A) modification near the stop codon of A3B, consequently increasing the stability of A3B mRNA. We further reveal that the demethylase FTO is responsible for As-reduced m6A modification of A3B, leading to increased A3B expression and DNA mutation rates in a manner dependent on the m6A reader YTHDF2. Our in vivo data also confirm that A3B is a downstream target of FTO in As-exposed lung tissues. In addition, FTO protein is highly expressed and positively correlates with the protein levels of A3B in tumor samples from human non-small cell lung cancer patients. These findings indicate a previously unrecognized role of A3B in As-triggered somatic mutation and might open new avenues to reduce DNA mutagenesis by targeting the FTO/m6A axis.

Palladium Nanoplate-Based IL-6 Receptor Antagonists Ameliorate Cancer-Related Anemia and Simultaneously Inhibit Cancer Progression.

In recent years, targeted therapies and immunotherapeutics, along with conventional chemo- and radiotherapy, have greatly improved cancer treatments. Unfortunately, in cancer patients, anemia, either as a complication of cancer progression or as the result of cancer treatment, undermines the expected therapeutic efficacy. Here, we developed a smart nanosystem based on the palladium nanoplates (PdPLs) to deliver tocilizumab (TCZ, a widely used IL-6R antibody) to the liver for specific blockade of IL-6/IL-6R signaling to correct anemia. With chemical modifications, this nanosystem delivered a large mass of TCZ and enhanced liver delivery, inducing a marked suppression of hepcidin expression as a result of diminished IL-6 signaling. Through this mechanism, significant suppression of tumor progression was realized (at least in part) because of the corrected anemia after treatment.

LncRNA MT1DP promotes cadmium-induced DNA replication stress by inhibiting chromatin recruitment of SMARCAL1.

Cadmium (Cd) is a well-known carcinogenic metal and widespread environmental pollutant. The effect of Cd-induced carcinogenesis is partly due to accumulated DNA damage and chromosomal aberrations, but the exact mechanisms underlying the genotoxicity of Cd have not been clearly understood. Here, we found that one long non-coding RNA MT1DP is participated in Cd-induced DNA damage and replication stress. Through analyzing the residents from Cd-contaminated area in Southern China, we found that blood DNA repair genes are down-regulated in individuals with high urine Cd values compared to those with low urine Cd values, which contrast to the blood MT1DP levels. Through in vitro experiments, we found that MT1DP promotes Cd-induced DNA damage response, genome instability and replication fork stalling. Mechanically, upon Cd treatment, ATR is activated to enhance HIF-1α expression, which in turn promotes the transcription level of MT1DP. Subsequently MT1DP is recruited on the chromatin and binds to SMARCAL1 to competitive inhibit latter's interaction with RPA complexes, finally leading to increased replication stress and DNA damage. In summary, this study provides clear evidence for the role of epigenetic regulation on the genotoxic effect of Cd, and MT1DP-mediated replication stress may represent a novel mechanism for Cd-induced carcinogenesis.

Terreuspyridine: An Unexpected Pyridine-Fused Meroterpenoid Alkaloid with a Tetracyclic 6/6/6/6 Skeleton from Aspergillus terreus.

Terreuspyridine (1), the first 3,5-demethylorsellinic acid (DMOA) derived meroterpenoid alkaloid, was isolated from the fungus Aspergillus terreus, which represents a new type of meroterpenoid possessing an unexpected tetracyclic 6/6/6/6 architecture. The structure of 1 with absolute configuration was determined by X-ray diffraction analysis. Biogenetically, it was proposed to be derived from the fusion of a DMOA-meroterpenoid and a glutamate. Terreuspyridine (1) exhibited moderate inhibitory activity against the BChE with an IC50 value of 16.4 µM.

Diethyldithiocarbamate-copper nanocomplex reinforces disulfiram chemotherapeutic efficacy through light-triggered nuclear targeting.

To circumvent the huge cost, long R&D time and the difficulty to identify the targets of new drugs, repurposing the ones that have been clinically approved has been considered as a viable strategy to treat different diseases. In the current study, we outlined the rationale for repurposing disulfiram (DSF, an old alcohol-aversion drug) to treat primary breast cancer and its metastases. Methods: To overcome a few shortcomings of the individual administration of DSF, such as the dependence on copper ions (Cu2+) and limited capability in selective targeting, we here artificially synthesized the active form of DSF, diethyldithiocarbamate (DTC)-Cu complex (CuET) for cancer therapeutics. To achieve a greater efficacy in vivo, smart nanomedicines were devised through a one-step self-assembly of three functional components including a chemically stable and biocompatible phase-change material (PCM), the robust anticancer drug (CuET) and a near-infrared (NIR) dye (DIR), namely CuET/DIR NPs. A number of in vitro assays were performed including the photothermal efficacy, light-triggered drug release behavior, nuclear localization, DNA damage and induction of apoptosis of CuET/DIR NPs and molecular mechanisms underlying CuET-induced repression on cancer metastatic behaviors. Meanwhile, the mice bearing 4T1-LG12-drived orthotopic tumors were employed to evaluate in vivo biodistribution and anti-tumor effect of CuET/DIR NPs. The intravenous injection model was employed to reflect the changes of the intrinsic metastatic propensity of 4T1-LG12 cells responding to CuET/DIR NPs. Results: The rationally designed nanomedicines have self-traceability for bioimaging, long blood circulation time for enhanced drug accumulation in the tumor site and photo-responsive release of the anticancer drugs. Moreover, our data unearthed that CuET/DIR nanomedicines behave like "Trojan horse" to transport CuET into the cytoplasm, realizing substantial intracellular accumulation. Upon NIR laser irradiation, massive CuET would be triggered to release from the nanomedicines and reach a high local concentration towards the nucleus, where the pro-apoptotic effects were conducted. Importantly, our CuET/DIR nanomedicines revealed a pronounced capability to leash breast cancer metastases through inhibition on EMT. Additionally, these nanomedicines showed great biocompatibility in animals. Conclusion: These combined data unearthed a remarkably enhanced tumor-killing efficacy of our CuET nanomedicines through nuclear targeting. This work may open a new research area of repurposing DSF as innovative therapeutic agents to treat breast cancer and its metastases.

Graphene Oxide Causes Disordered Zonation Due to Differential Intralobular Localization in the Liver.

The liver is the primary organ to sequester nanodrugs, representing a substantial hurdle for drug delivery and raising toxicity concerns. However, the mechanistic details underlying the liver sequestration and effects on the liver are still elusive. The difficulty in studying the liver lies in its complexity, which is structured with stringently organized anatomical units called lobules. Graphene oxide (GO) has attracted attention for its applications in biomedicine, especially as a nanocarrier; however, its sequestration and effects in the liver, the major enrichment and metabolic organ, are less understood. Herein, we unveiled the differential distribution of GO in lobules in the liver, with a higher amount surrounding portal triad zones than the central vein zones. Strikingly, liver zonation patterns also changed, as reflected by changes in vital zonated genes involved in hepatocyte integrity and metabolism, leading to compromised hepatic functions. RNA-Seq and DNA methylation sequencing analyses unraveled that GO-induced changes in liver functional zonation could be ascribed to dysregulation of key signaling pathways governing liver zonation at not only mRNA transcriptions but also DNA methylation imprinting patterns, partially through TET-dependent signaling. Together, this study reveals the differential GO distribution pattern in liver lobules and pinpoints the genetic and epigenetic mechanisms in GO-induced liver zonation alterations.

Asperpyridone A: An Unusual Pyridone Alkaloid Exerts Hypoglycemic Activity through the Insulin Signaling Pathway.

A pyridone alkaloid, asperpyridone A (1), which possesses an unusual pyrano[3,2-c]pyridine scaffold, was isolated from solid cultures of the endophytic fungus Aspergillus sp. TJ23. Its structure, including its absolute configuration, was determined using a combination of nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, quantum chemical calculations (electronic circular dichroism), and X-ray crystallography. In vitro bioassays demonstrated that asperpyridone A (1) could function as a potential hypoglycemic agent, which exhibited pronounced glucose uptake effect in liver HepG2 cells, under both normal and insulin-resistant conditions, with higher efficacy than metformin. The underlying mechanism of asperpyridone A was elucidated by analyzing the genes expressed, the Gene Ontology (GO) function enrichment, the protein interaction network, and real-time quantitative reverse transcription polymerase chain reaction, which suggested that asperpyridone A exhibits hypoglycemic activity by activating the insulin signaling pathway. Moreover, on the basis of the hypoglycemic potency, fibroblast growth factor 21 (FGF21) was determined to be a potential target for asperpyridone A.

The diagnostic value of metagenomic next-generation sequencing for identifying Streptococcus pneumoniae in paediatric bacterial meningitis.

BACKGROUND: There is currently no research on the diagnostic value of metagenomic next-generation sequencing (mNGS) for a single pathogens in CSF. The aim of this study was to analyse the value of mNGS for identifying Streptococcus pneumoniae (S. pneumoniae) in paediatric bacterial meningitis. METHODS: Bacterial meningitis (BM) cases from October 23, 2014, to December 31, 2016, and December 1, 2017, to July 31, 2018 at Beijing Children's Hospital were reviewed. Clinical features and pathogens were analysed. RESULTS: We diagnosed 135 patients with BM in this study. A total of 43 S. pneumoniae were identified by combination methods. 26/135 (19.3%) patients had positive results in S. pneumoniae by blood and/or cerebrospinal fluid (CSF) culture. Alere BinaxNow®Streptococcus pneumoniae Antigen test was positive in 35/135(25.9%) cases. 32/135 (23.7%) S. pneumoniae were identified by mNGS. Six CSF samples were identified as S. pneumoniae only by mNGS technology. Taking culture as the gold standard, the sensitivity and specificity of mNGS for diagnosing S. pneumoniae meningitis were 73.1 and 88.1%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of diagnosing S. pneumoniae meningitis by mNGS were 59.4 and 93.2%, respectively. When comparison between mNGS and combined tests (culture and Alere BinaxNow®Streptococcus pneumoniae Antigen test), the sensitivity and specificity of mNGS for S. pneumoniae identification were 70.3 and 93.9%, the PPV and NPV in the identification of S. pneumoniae by mNGS were 81.4 and 89.3%, respectively. The difference in number of unique reads of S. pneumoniaein from CSF sample (< 14 days onset) and CSF sample (> 14 days from onset) was statistically significant (170.5 VS. 13, P = 0.019). The difference in the collected time of CSF for culture and mNGS was statistically significant (4 days VS. 14 days, P < 0.001). CONCLUSIONS: mNGS has high sensitivity and specificity for S. pneumoniae identification. The pathogen load (number of unique reads) of S. pneumonia is related to the CSF collection time. mNGS was less affected than culture by the use of antibiotics before CSF collection.

Highly oxygenated meroterpenoids from the Antarctic fungus Aspergillus terreus.

Eleven highly oxygenated meroterpenoids, named terreustoxins A-K, along with five known analogues, were isolated from the Antarctic fungus Aspergillus terreus. The structures and absolute configurations of these undescribed compounds were characterized by NMR spectroscopy, single-crystal X-ray crystallography, and ECD experiments. Terreustoxins A-D are the first examples of meroterpenoids with two ortho-hydroxy groups at C-6 and C-7 in the terretonins family. Terreustoxin C and terretonin inhibited the proliferation of Con A-induced murine T cells at the concentration of 10 µM.

Evaluation of next-generation sequencing for the pathogenic diagnosis of children brain abscesses.

In this study, we applied metagenomic next-generation sequencing (mNGS) to detect the causative pathogens in brain abscess samples from 4 pediatric patients. NGS could offer unbiased sequencing and rapid diagnosis of causative pathogens, moreover, it could detect multiple pathogenic microorganisms from abscess samples. In our study, Fusobacterium nucleatum, and Streptococcus intermedius or combinations of them were found in 3/4 of polymicrobial brain abscesses. Internal organ abscesses are illustrative of the shortcomings of bacterial culture. NGS has the ability to identify both common and rare pathogens without any prior suspicious needed, and is able to offer a new platform for quantification of all detected microorganisms. Our study displayed the possible potential that NGS is about to provide the diagnostic tools that can characterize even the most complex microbial communities during brain abscesses and is less affected by prior antibiotic exposure.

Chiral ligand exchange capillary electrochromatography with dual ligands for enantioseparation of D,L-amino acids.

Utilizing block copolymers as coatings, a protocol of chiral ligand exchange capillary electrochromatography (CLE-CEC) protocol was designed and developed with dual ligands for D,L-amino acids enantioseparation. Four block copolymers including poly maleic anhydride-co-styrene-co-N-methacryloyl-L-histidine methyl ester [P(MAn-St-MAH)], poly maleic anhydride-co-styrene-co-N-methacryloyl-L-lysine methyl ester [P(MAn-St-MAL)], poly maleic anhydride-co-styrene-co-N-methacryloyl-L-phenylalanine methyl ester [P(MAn-St-MAP)] and poly maleic anhydride-co-styrene-co-N-methacryloyl-L-threonine methyl ester [P(MAn-St-MAT)] were synthesized by reversible addition fragmentation chain transfer polymerization reaction. Key factors affecting the enantioresolution were optimized, including the concentration of Zn (II) central ion, pH value of buffer solution and monomers of the block copolymers. The enantioresolution of the proposed CLE-CEC system could be enhanced dramatically by employing P(MAn-St-MAH) as the immobilized chiral ligand and by coordinating the synergistic effect of free ligand in buffer solution. The principle of improved enantioresolution of the CLE-CEC system with dual ligands was discussed. Well enantioseparation was successfully realized with 7 pairs of D,L-amino acids enantiomers baseline separation and 5 pairs part separation. For quantitative analysis of D,L-alanine, a good linearity was established in the range of 9.4 µM to 1.5 mM (r2 = 0.997) with the limits of detection (LODs) 3.7 µM of D-alanine, 2.0 µM for L-alanine, and limits of quantification (LOQs) 9.0 µM for D-alanine and 6.0 µM for L-alanine. The peak area and migration time reproducibility (n = 6) were 4.1% and 3.5% for D-alanine, 3.7% and 3.1% for L-alanine. Further, the enzyme kinetics study of alanine aminotransferase was investigated with the constructed CLE-CEC system.