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UNLABELLED: Methyl-coenzyme M reductase (MCR) catalyzes the final step of methanogenesis, the microbial metabolism responsible for nearly all biological methane emissions to the atmosphere. Decades of biochemical and structural research studies have generated detailed insights into MCR function in vitro, yet very little is known about the interplay between MCR and methanogen physiology. For instance, while it is routinely stated that MCR catalyzes the rate-limiting step of methanogenesis, this has not been categorically tested. In this study, to gain a more direct understanding of MCRs control on the growth of Methanosarcina acetivorans, we generate a strain with an inducible mcr operon on the chromosome, allowing for careful control of MCR expression. We show that MCR is not growth rate-limiting in substrate-replete batch cultures. However, through careful titration of MCR expression, growth-limiting state(s) can be obtained. Transcriptomic analysis of M. acetivorans experiencing MCR limitation reveals a global response with hundreds of differentially expressed genes across diverse functional categories. Notably, MCR limitation leads to strong induction of methylsulfide methyltransferases, likely due to insufficient recycling of metabolic intermediates. In addition, the mcr operon is not transcriptionally regulated, i.e., it is constitutively expressed, suggesting that the overabundance of MCR might be beneficial when cells experience nutrient limitation or stressful conditions. Altogether, we show that there is a wide range of cellular MCR concentrations that can sustain optimal growth, suggesting that other factors such as anabolic reactions might be rate-limiting for methanogenic growth. IMPORTANCE: Methane is a potent greenhouse gas that has contributed to ca. 25% of global warming in the post-industrial era. Atmospheric methane is primarily of biogenic origin, mostly produced by microorganisms called methanogens. Methyl-coenzyme M reductase (MCR) catalyzes methane formatio in methanogens. Even though MCR comprises ca. 10% of the cellular proteome, it is hypothesized to be growth-limiting during methanogenesis. In this study, we show that Methanosarcina acetivorans cells grown in substrate-replicate batch cultures produce more MCR than its cellular demand for optimal growth. The tools outlined in this study can be used to refine metabolic models of methanogenesis and assay lesions in MCR in a higher-throughput manner than isolation and biochemical characterization of pure protein.

We describe the genome of an Eremiobacterota population from tundra soil that contains the minimal set of nif genes needed to fix atmospheric N2. This putative diazotroph population, which we name Candidatus Lamibacter sapmiensis, links for the first time Eremiobacterota and N2 fixation. The integrity of the genome and its nif genes are well supported by both environmental and taxonomic signals. Ca. Lamibacter sapmiensis contains three nifH homologues and the complementary set of nifDKENB genes that are needed to assemble a functional nitrogenase. The putative diazotrophic role of Ca. Lamibacter sapmiensis is supported by the presence of genes that regulate N2 fixation and other genes involved in downstream processes such as ammonia assimilation. Similar to other Eremiobacterota, Ca. Lamibacter sapmiensis encodes the potential for atmospheric chemosynthesis via CO2 fixation coupled with H2 and CO oxidation. Interestingly, the presence of a N2O reductase indicates that this population could play a role as a N2O sink in tundra soils. Due to the lack of activity data, it remains uncertain if Ca. Lamibacter sapmiensis is able to assemble a functional nitrogenase and participate in N2 fixation. Confirmation of this ability would be a testament to the great metabolic versatility of Eremiobacterota, which appears to underlie their ecological success in cold and oligotrophic environments.

The sources and sinks of nitrous oxide, as control emissions to the atmosphere, are generally poorly constrained for most environmental systems. Initial depth-resolved analysis of nitrous oxide flux from observation wells and the proximal surface within a nitrate contaminated aquifer system revealed high subsurface production but little escape from the surface. To better understand the environmental controls of production and emission at this site, we used a combination of isotopic, geochemical, and molecular analyses to show that chemodenitrification and bacterial denitrification are major sources of nitrous oxide in this subsurface, where low DO, low pH, and high nitrate are correlated with significant nitrous oxide production. Depth-resolved metagenomes showed that consumption of nitrous oxide near the surface was correlated with an enrichment of Clade II nitrous oxide reducers, consistent with a growing appreciation of their importance in controlling release of nitrous oxide to the atmosphere. Our work also provides evidence for the reduction of nitrous oxide at a pH of 4, well below the generally accepted limit of pH 5.

A major limitation to developing chimeric antigen receptor (CAR)-T cell therapies for solid tumors is identifying surface proteins highly expressed in tumors but not in normal tissues. Here, we identify Tyrosinase Related Protein 1 (TYRP1) as a CAR-T cell therapy target to treat patients with cutaneous and rare melanoma subtypes unresponsive to immune checkpoint blockade. TYRP1 is primarily located intracellularly in the melanosomes, with a small fraction being trafficked to the cell surface via vesicular transport. We develop a highly sensitive CAR-T cell therapy that detects surface TYRP1 in tumor cells with high TYRP1 overexpression and presents antitumor activity in vitro and in vivo in murine and patient-derived cutaneous, acral and uveal melanoma models. Furthermore, no systemic or off-tumor severe toxicities are observed in an immunocompetent murine model. The efficacy and safety profile of the TYRP1 CAR-T cell therapy supports the ongoing preparation of a phase I clinical trial.

Background: Chronic alcohol users often exhibit an increased minimum alveolar concentration (MAC) of sevoflurane, yet the specific mechanism remains unclear. It has been reported that ethanol exposure can upregulate the protein expression and enzyme activity of cytochrome P450 2E1 (CYP2E1). CYP2E1 is a key enzyme that converts 2–5% of sevoflurane into equimolar amounts of hexafluoroisopropanol (HFIP) and F−. This study aims to explore whether ethanol exposure could alter sevoflurane metabolism through CYP2E1 modulation, potentially explaining the increased MAC observed in alcohol users. Methods: Eighty adult male Sprague-Dawley (SD) rats were randomly divided into two groups and received either 50% ethanol (dose: 3 g/kg) or 0.9% saline twice daily by gavage. After 1, 2, 3, and 4 weeks of gavage, ten rats were randomly selected from each group to undergo 1-hour anesthesia with 2.3% sevoflurane. Blood samples were collected after anesthesia to measure the concentration of free HFIP using gas chromatography. Additionally, the left lobe tissue of the liver was collected for the analysis of CYP2E1 protein expression by Western blot and CYP2E1 enzyme activity by colorimetric assay. Correlations between these parameters were analyzed using Pearson's correlation. Results: In the ethanol group, CYP2E1 expression, activity, and the concentration of free HFIP were significantly higher at all time points compared to the control group (P < 0.05), except for protein expression in the first week (P > 0.05). Within-group comparisons indicated no significant changes in any of the parameters for the control group (P > 0.05). In the ethanol group, there was no difference in free HFIP concentration between the first and second weeks (P > 0.05), but a significant increase was observed in the third and fourth weeks (P < 0.01); protein expression and enzyme activity significantly varied over time, especially showing a notable increase from the first to the third and fourth weeks (P < 0.05). Correlation analysis revealed strong positive correlations between free HFIP concentration and CYP2E1 activity (r = 0.7898), free HFIP concentration and CYP2E1 expression (r = 0.8418), and CYP2E1 activity and expression (r = 0.8740), all with P < 0.001. Conclusions: Ethanol exposure increased both the expression and enzymatic activity of CYP2E1, consequently enhancing the metabolism of sevoflurane. [ABSTRACT FROM AUTHOR]

Background: Bone loss caused by microgravity exposure presents a serious threat to the health of astronauts, but existing treatment strategies have specific restrictions. This research aimed to investigate whether salidroside (SAL) can mitigate microgravity-induced bone loss and its underlying mechanism. Methods: In this research, we used hindlimb unloading (HLU) and the Rotary Cell Culture System (RCCS) to imitate microgravity in vivo and in vitro. Results: The results showed that salidroside primarily enhances bone density, microstructure, and biomechanical properties by stimulating bone formation and suppressing bone resorption, thereby preserving bone mass in HLU rats. In MC3T3-E1 cells cultured under simulated microgravity in rotary wall vessel bioreactors, the expression of osteogenic genes significantly increased after salidroside administration, indicating that salidroside can promote osteoblast differentiation under microgravity conditions. Furthermore, the Nrf2 inhibitor ML385 diminished the therapeutic impact of salidroside on microgravity-induced bone loss. Overall, this research provides the first evidence that salidroside can mitigate bone loss induced by microgravity exposure through stimulating the Nrf2/HO-1 pathway. Conclusion: These findings indicate that salidroside has great potential for treating space-related bone loss in astronauts and suggest that Nrf2/HO-1 is a viable target for counteracting microgravity-induced bone damage. [ABSTRACT FROM AUTHOR]

Simple Summary: Oropharyngeal Squamous Cell Carcinoma (OPSCC) represents a significant fraction of head and neck cancers, with a challenging five-year survival rate of only 50%. Key risk factors include tobacco and alcohol consumption and infection with human papillomavirus (HPV), particularly HPV16. Distinct biological differences exist between HPV-positive and HPV-negative OPSCC, including differences in mutation patterns and gene expression profiles. This study focuses on aldo-keto reductases (AKRs), specifically AKR1C2, which are involved in cellular stress management and detoxification processes, particularly in cisplatin-resistant tumors. This study investigates the role of AKR1C2 in HPV-positive OPSCC and its effect on patient outcomes. The findings indicate that increased levels of AKR1C2 are linked to unfavorable prognosis, particularly in male patients, while higher levels in female patients indicate a favorable prognosis. Head and Neck Squamous Cell Carcinoma (HNSCC), particularly Oropharyngeal Squamous Cell Carcinoma (OPSCC), is a major global health challenge due to its increasing incidence and high mortality rate. This study investigates the role of aldo-keto reductase 1C2 (AKR1C2) in OPSCC, focusing on its expression, correlation with Human Papillomavirus (HPV) status, oxidative stress status, and clinical outcomes, with an emphasis on sex-specific differences. We analyzed AKR1C2 expression using immunohistochemistry in formalin-fixed, paraffin-embedded tissue samples from 51 OPSCC patients. Additionally, we performed RT-qPCR in cultured HPV16-E6*I and HPV16-E6 overexpressing HEK293 cell lines (p53WT). Statistical analyses were performed to assess the correlation between AKR1C2 expression and patient data. Our results indicate a significant association between increased AKR1C2 expression and higher AJCC classification (p = 0.009) as well as positive HPV status (p = 0.008). Prognostic implications of AKR1C2 varied by sex, whereby female patients with high AKR1C2 expression had better overall survival, whereas male patients exhibited poorer outcomes. Additionally, AKR1C2 expression was linked to HPV status, suggesting a potential HPV-specific regulatory mechanism. These findings underscore the complex interplay among AKR1C2, HPV, and patient sex, highlighting the need for personalized treatment strategies for OPSCC. Targeted inhibition of AKR1C2, considering sex-specific differences, may enhance therapeutic outcomes. Future research should investigate these mechanisms to enhance treatment efficacy. [ABSTRACT FROM AUTHOR]

Background: In the postacute phase of coronavirus disease-2019 (COVID-19), survivors may have persistent symptoms, lung function abnormalities, and sequelae lesions on thoracic computed tomography (CT). This new entity has been defined as post-COVID interstitial lung disease (ILD) or residual disease. Aims: To evaluate the characteristics, risk factors and clinical significance of post-COVID ILD. Study Design: Multicenter cross-sectional analysis of data from a randomized clinical study. Methods: In this study, patients with persistent respiratory symptoms 3 months after recovery from COVID-19 were evaluated by two pulmonologists and a radiologist. post-COVID ILD was defined as the presence of respiratory symptoms, hypoxemia, restrictive defect on lung function tests, and interstitial changes on follow-up high-resolution computed tomography (HRCT). Results: At the three-month follow-up, 375 patients with post-COVID-19 syndrome were evaluated, and 262 patients were found to have post- COVID ILD. The most prevalent complaints were dyspnea (n = 238, 90.8%), exercise intolerance (n = 166, 63.4%), fatigue (n = 142, 54.2%), and cough (n = 136, 52%). The mean Medical Research Council dyspnea score was 2.1 ± 0.9, oxygen saturation was 92.2 ± 5.9%, and 6-minute walking distance was 360 ± 140 meters. The mean diffusing capacity of the lung for carbon monoxide was 58 ± 21, and the forced vital capacity was 70% ± 19%. Ground glass opacities and fibrotic bands were the most common findings on thoracic HRCT. Fibrosis-like lesions such as interlobular septal thickening and traction bronchiectasis were observed in 38.3% and 27.9% of the patients, respectively. No honeycomb cysts were observed. Active smoking [odds ratio (OR), 1.96; 95% confidence interval (CI), 1.44-2.67), intensive care unit admission during the acute phase (OR, 1.46; 95% CI, 1.1-1.95), need for high-flow nasal oxygen (OR, 1.55; 95% CI, 1.42-1.9) or non-invasive ventilation (OR, 1.31; 95% CI, 0.8-2.07), and elevated serum lactate dehydrogenase levels (OR, 1.23; 95% CI 1.18-1.28) were associated with the development of post-COVID ILD. At the 6-month follow-up, the respiratory symptoms and pulmonary functions had improved spontaneously without any specific treatment in 35 patients (13.4%). The radiological interstitial lesions had spontaneously regressed in 54 patients (20.6%). Conclusion: The co-existence of respiratory symptoms, radiological parenchymal lesions, and pulmonary functional abnormalities which suggest a restrictive ventilatory defect should be defined as post-COVID-19 ILD. However, the term "fibrosis" should be used carefully. Active smoking, severe COVID-19, and elevated lactate dehydrogenase level are the main risk factors of this condition. These post-COVID functional and radiological changes could disappear over time in 20% of the patients. [ABSTRACT FROM AUTHOR]

In terms of prevalence, 11β-hydroxylase deficiency (11β-OHD), a common form of congenital adrenal hyperplasia, closely follows 21-hydroxylase deficiency. 11β-OHD has been attributed to diminished enzymatic activity owing to CYP11B1 gene variants, mainly encompassing single nucleotide variations and insertions-deletions. The involvement of chimeric CYP11B2/CYP11B1 genes in 11β-OHD has rarely been reported. We conducted a genetic investigation on a male infant with generalized pigmentation and abnormal steroid hormone levels. Whole-exome sequencing revealed a heterozygous variant in CYP11B1 inherited from the mother (NM_000497.4: c.1391_1393dup [p.Leu464dup]). Long-range polymerase chain reaction revealed an additional allele, a chimeric CYP11B2/CYP11B1 gene, inherited from the father. The current case report highlights the need to consider the occurrence of gene fusion variants in the diagnosis of neonatal or early infantile 11β-OHD. [ABSTRACT FROM AUTHOR]

Background Cardiac injury caused by iron overload is the leading cause of mortality and morbidity in patients with beta-thalassemia, owing to frequent blood transfusion, increased iron overload, and blood hemolysis. Objective This research aimed to assess several novel cardiac biomarkers in the blood samples of children and adult patients with beta-thalassemia major (βTM), along with their respective control groups. These biomarkers included endothelin 1 (ET-1), N-terminal pro-brain natriuretic peptide (NT-proBNP), atrial natriuretic peptide (ANP), growth differentiation factor-15 (GDF-15), and renalase (RNLS). Methods This case-control study was done on 46 patients with βTM (23 children <18 years, and 23 adults ≥18 years) from the Genetic Hematology Center in Thi-Qar province, Iraq, and 42 comparable controls in 2 groups (21 for each group) in the period from February to April 2023. Results Levels of ET-1, NT-proBNP, ANP, GDF-15, RNLS, and ferritin were higher in the children and adults with βTM than in the control subjects. Conclusion Elevations of the novel cardiac biomarkers ET-1, NT-proBNP, ANP, GDF-15, and RNLS in the sera of children and adult patients with βTM when compared with comparable control subjects confirm that the majority of patients with βTM are at risk of cardiac and cardiovascular complications even when there are no obvious symptoms, especially in children, which gives suitable predictive biomarkers. [ABSTRACT FROM AUTHOR]

Inherited metabolic diseases, as a first presentation in adults, are an under‐recognised condition associated with significant morbidity and mortality. Diagnosis is challenging because of non‐specific clinical and biochemical findings, resemblance to common conditions such as neuropsychiatric disorders and the misconception that these disorders predominantly affect paediatric populations. We describe a series of patients with multiple acyl‐CoA dehydrogenase deficiency (MADD)/MADD‐like disorders to highlight these diagnostic challenges. [ABSTRACT FROM AUTHOR]

Background: Pauci‐immune glomerulonephritis (GN) due to antineutrophil cytoplasmic antibody (ANCA)‐associated vasculitis (AAV) is a common cause of crescentic GN. Despite advances in treatment, rates of mortality and progression to end‐stage kidney disease remain high. Renal involvement is diagnosed by histological examination of kidney tissue. Serum ANCAs play a significant role in AAV; however, the value of serum ANCA quantification to predict renal involvement is not well‐established. Aim: We aimed to evaluate the diagnostic accuracy of serum ANCA titres in diagnosing AAV with renal involvement. Methods: We conducted a retrospective study of consecutive native kidney biopsies reported at our centre from 2016 to 2021. We included all adults who had both a kidney biopsy and ANCA serology. ANCA serology was tested using indirect immunofluorescence with reporting of titres. Antibodies to proteinase 3 and myeloperoxidase were measured using a chemiluminescent immunoassay. Results: Eight hundred and forty‐eight native kidney biopsies were reported during the study period. Five hundred and seven cases were included. The biopsy prevalence of pauci‐immune GN in paired samples was 41/507 (8.1%). Most of the cohort had haematuria (66.6%), proteinuria (93.4%) and/or acute kidney injury (65.0%). A positive ANCA at any titre demonstrated a sensitivity of 97.6% and a specificity of 71.2% for a diagnosis of pauci‐immune GN. The area under the curve for the receiver operator characteristic was 0.93 (95% confidence interval [CI]: 0.89–0.97). A cutoff ANCA titre of 1:160 provided the optimum balance between a sensitivity of 75.6% (95% CI: 59.7%–87.6%) and a specificity of 94.0% (95% CI: 91.6%–96.0%). Conclusions: ANCA titres are highly predictive of pauci‐immune GN in the appropriate context. While serum ANCA quantitation may not replace renal biopsy, reporting will assist in the decision to start treatment early for patients with organ or life‐threatening disease. [ABSTRACT FROM AUTHOR]

Objective Idiopathic inflammatory myopathies (IIM) are a heterogeneous and life-threatening group of diseases; in particular, anti-melanoma differentiation-associated gene 5 antibody positive DM (MDA5+ DM) is reportedly strongly associated with high mortality rate. Tacrolimus (TAC) provides an excellent therapeutic option, but the trough concentration (Cmin)–outcome relationship remains unexplored. This study was undertaken to identify optimal Cmin and individualized dose based on CYP3A5 genotype for IIM patients. Methods A total of 134 IIM patients with 467 Cmin were enrolled. We examined the relationship between TAC Cmin and relapses. The receiver operating characteristic analysis was used to confirm the optimal Cmin. Analyses of factors influencing Cmin were conducted. The dose requirement based on CYP3A5 genotype was confirmed. Results TAC Cmin is strongly associated with relapses. The optimal cutoff values were 5.30, 5.85, 4.85 and 5.35 ng/ml for acute, subacute, chronic and all-phase IIM patients (P   =  0.001, 0.013, 0.002 and <0.001, respectively), as well as 5.35, 5.85, 5.55 and 5.85 ng/ml for acute, subacute, chronic and all-phase MDA5+ DM patients (P   =  0.007, 0.001, 0.036 and <0.001, respectively). CYP3A5 genotype was one of the significant factors influencing TAC Cmin. CYP3A5 expressers required 0.059 mg/kg/day to attain the target Cmin, while nonexpressers required 0.046 mg/kg/day (P   =  0.019). Conclusion TAC treatment may elicit favorable outcome in patients with IIM and MDA5+ DM when Cmin exceeded 5.35 and 5.85 ng/ml, which is crucial to a lower relapse rate. The individualized dose based on the CYP3A5 genotype provides a reference for TAC personalized therapy in IIM. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the effect of plasma‐activated Ringer's lactate solution (PAL) on oral squamous cell carcinoma (OSCC) cells and carcinogenic processes with a particular focus on iron and collagenous matrix formation. Materials and Methods: We used three OSCC cell lines, one keratinocyte cell line, and two fibroblast lines, and cell viability assays, immunoblotting, flow cytometry, and transmission electron microscopy were performed to evaluate the effect and type of cell death. The effect of PAL treatment on lysyl oxidase (LOX) expression was investigated in vitro and in vivo. Tamoxifen‐inducible Mob1a/b double‐knockout mice were used for the in vivo experiment. Results: PAL killed OSCC cells more effectively than the control nontumorous cells and suppressed cell migration and invasion. Ferroptosis occurred and the protein level of LOX was downregulated in cancer cells in vitro and in vivo. Additionally, PAL improved the survival rate of mice and suppressed collagenous matrix formation. Conclusions: We demonstrated that PAL specifically kills OSCC cells and that ferroptosis occurs in vitro and in vivo. Furthermore, PAL can prevent carcinogenesis and improve the survival rate of oral cancer, especially tongue cancer, by changing collagenous matrix formation via LOX suppression. [ABSTRACT FROM AUTHOR]

Background: Here, we evaluated whether the histone lysine demethylase 5B (JARID1B), is involved in osteogenic phenotype commitment of periodontal ligament cells (PDLCs), by considering their heterogeneity for osteoblast differentiation. Materials and Methods: Epigenetic, transcriptional, and protein levels of a gene set, involved in the osteogenesis, were investigated by performing genome‐wide DNA (hydroxy)methylation, mRNA expression, and western blotting analysis at basal (without osteogenic induction), and at the 3rd and 10th days of osteogenic stimulus, in vitro, using PDLCs with low (l) and high (h) osteogenic potential as biological models. Results: h‐PDLCs showed reduced levels of JARID1B, compared to l‐PDLCs, with significant inversely proportional correlations between RUNX2 and RUNX2/p57. Epigenetically, a significant reduction in the global H3K4me3 content was observed only in h‐PDLCs. Immunoblotting data reveal a significant reduction in the global H3K4me3 content, at 3 days of induction only in h‐PDLCs, while an increase in the global H3K4me3 content was observed at 10 days for both PDLCs. Additionally, positive correlations were found between global H3K4me3 levels and JARID1B gene expression. Conclusions: Altogether, our results show the crucial role of JARID1B in repressing PDLCs osteogenic phenotype and this claims to pre‐clinical protocols proposing JARID1B as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Treatment of ocular diseases presents unique challenges and opportunities for the clinician and for the clinical pharmacologist. Ophthalmic pharmaceuticals, typically given as liquids, require consideration of solubility, physiological pH, and osmolarity, as well as sterility and stability, which in turn requires optimal pharmaceutics. Ocular tissue levels are challenging to obtain in humans, and the clinical pharmacokinetics is typically blood levels, which are primarily related to safety, rather than efficacy. The eye is a closed compartment with multiple physiological barriers with esterases and transporters, but relatively little cytochrome oxidases. Delivery routes include topical, intravitreal, and systemic. Patient dosing involves not only adherence issues common to all chronic diseases, but also performance requirements on eye drop instillation. Therapeutically, ocular diseases and their pharmacological treatments include both those analogous to systemic diseases (e.g., inflammation, infection, and neuronal degeneration) and those unique to the eye (e.g., cataract and myopia). [ABSTRACT FROM AUTHOR]

The methanol extract of Inula viscosa (IVM) was investigated for its antioxidant potential using the DPPH and ABTS radical scavenging as well as iron chelating assays (ICA). The total phenol (TPC) and flavonoid contents (TFC) of IVM were determined using the Folin-Ciocalteu and aluminum trichloride methods, respectively. Antimicrobial activity of different concentrations of I. viscosa methanol extract was investigated by disc diffusion and broth microdilution method. The IVM extract was found to be containing TPC (236.78 ± 7.63 mg GAE/g) and TFC (94.36 ± 1.86 mg QE/g). Antioxidant activity IC50 values for the DPPH, ABTS and ICA assays were found to be 277.7 ± 3.68, 2.44 ± 0.02, and 222.1 ± 0.71 µg/mL, respectively. The MIC values of the IVM on the tested microorganisms ranged from 0.48 to 7.81 mg/mL. Furthermore, IVM extract was demonstrated 18.32 ± 1.37%, 23.06 ± 1.05%, 4.72 ± 0.13%, 15.13 ± 0.37% and 37.64 ± 4.02% inhibition against tyrosinase, α-amylase, α-glucosidase, AChE and BChE, respectively. In the results of LC-MS/MS analysis, acacetin, quercetin, chlorogenic acid and protocatechuic acid were determined as most dominant compounds. These findings suggested that this plant may be a natural resource for creating novel medicinal compounds. [ABSTRACT FROM AUTHOR]

Background: Hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors are an oral treatment for anemia of chronic kidney disease (CKD). In this systematic review and meta-analysis, we assessed long-term safety of HIF prolyl hydroxylase inhibitors. Methods: We searched MEDLINE, Embase, and Cochrane databases for randomized trials comparing HIF prolyl hydroxylase inhibitors with an erythropoiesis-stimulating agent (ESA) or placebo with greater than or equal to 48 weeks of follow-up. The primary outcome was major adverse cardiovascular event (MACE), defined as a composite of all-cause death, myocardial infarction, or stroke. Treatment effects were pooled using random-effects models. Results: Twenty-five trials involving 26,478 participants were included. Of these, 13 trials enrolled 13,230 participants with dialysis-dependent CKD, and 12 trials enrolled 13,248 participants with nondialysis-dependent CKD. There was no evidence that HIF prolyl hydroxylase inhibitors and ESA had different effects on MACE in people with dialysis-dependent CKD (risk ratio, 0.99; 95% confidence interval [CI], 0.92 to 1.08) or people with nondialysis-dependent CKD (risk ratio, 1.08; 95% CI, 0.95 to 1.22). Similarly, there was no evidence that HIF prolyl hydroxylase inhibitors and placebo had different effects on MACE (risk ratio, 1.10; 95% CI, 0.96 to 1.27) in people with nondialysis-dependent CKD. The lack of difference between HIF prolyl hydroxylase inhibitors and ESA or placebo was observed for individual components of MACE and cardiovascular death. Safety of HIF prolyl hydroxylase inhibitors for other outcomes was comparable with ESA in dialysis-dependent CKD. In nondialysis-dependent CKD, dialysis access thrombosis, venous thromboembolism, infections, and hyperkalemia occurred more frequently with HIF prolyl hydroxylase inhibitors in placebo-controlled trials but not in ESA-controlled trials. Conclusions: There was no evidence of a difference in the long-term cardiovascular safety profile of HIF prolyl hydroxylase inhibitors and ESA in adults with dialysis-dependent CKD and adults with nondialysis-dependent CKD. (PROSPERO registration number, CRD42021278011.) [ABSTRACT FROM AUTHOR]

Introduction High-grade serous ovarian cancer (HGSOC) is characterized by high mortality and prevalent recurrences. This study investigates the prognostic value of phosphoglycerate dehydrogenase (PHGDH) in HGSOC which has been linked to metabolic reprogramming and recurrences in other cancers. Methods Data from 306 patients with advanced-stage HGSOC treated between 2008 and 2015 were analyzed. PHGDH expression levels were determined using immunohistochemistry and categorized as "low" or "high." Results PHGDH-high was associated with higher FIGO stage and increased use of neoadjuvant chemotherapy. Patients with PHGDH-high tumors had significantly worse survival than PHDH-low, even after adjusting for confounding factors. [ABSTRACT FROM AUTHOR]

AbstractCompounds containing chiral C–N bonds play a vital role in the composition of biologically active natural products and small pharmaceutical molecules. Therefore, the development of efficient and convenient methods for synthesizing compounds containing chiral C–N bonds is a crucial area of research. Nicotinamide-dependent oxidoreductases (NDOs) emerge as promising biocatalysts for asymmetric synthesis of chiral C–N bonds due to their mild reaction conditions, exceptional stereoselectivity, high atom economy, and environmentally friendly nature. This review aims to present the structural characteristics and catalytic mechanisms of various NDOs, including imine reductases/ketimine reductases, reductive aminases, EneIRED, and amino acid dehydrogenases. Additionally, the review highlights protein engineering strategies employed to modify the stereoselectivity, substrate specificity, and cofactor preference of NDOs. Furthermore, the applications of NDOs in synthesizing essential medicinal chemicals, such as noncanonical amino acids and chiral amine compounds, are extensively examined. Finally, the review outlines future perspectives by addressing challenges and discussing the potential of utilizing NDOs to establish efficient biosynthesis platforms for C–N bond synthesis. In conclusion, NDOs provide an economical, efficient, and environmentally friendly toolbox for asymmetric synthesis of C–N bonds, thus contributing significantly to the field of pharmaceutical chemical development. [ABSTRACT FROM AUTHOR]

Simple Summary: This study identified the risk factors of non-local recurrence of isocitrate dehydrogenase (IDH) wild-type glioblastoma, a highly aggressive brain tumor. We found that subventricular zone involvement significantly increased the risk of non-local recurrence, with the tumor contacting the trigone of the lateral ventricle and tending to develop subependymal dissemination. A meta-analysis of previous studies confirmed subventricular zone involvement and O-6-methylguanine DNA methyltransferase promoter methylation as risk factors for non-local recurrence. In contrast, ventricular opening via surgery did not increase the risk of non-local recurrence. These findings emphasize the need for tailored therapeutic strategies based on tumor location and molecular characteristics and provide valuable guidance for clinical decision-making in managing recurrent glioblastoma. Isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) is a highly aggressive brain tumor with a high recurrence rate despite adjuvant treatment. This study aimed to evaluate the risk factors for non-local recurrence of GBM. In the present study, we analyzed 104 GBMs with a single lesion (non-multifocal or multicentric). Univariate analysis revealed that subventricular zone (SVZ) involvement was significantly associated with non-local recurrence (hazard ratio [HR]: 2.09 [1.08–4.05]). Tumors in contact with the trigone of the lateral ventricle tended to develop subependymal dissemination (p = 0.008). Ventricular opening via surgery did not increase the risk of non-local recurrence in patients with SVZ involvement (p = 0.190). A systematic review was performed to investigate the risk of non-local recurrence, and 21 studies were identified. A meta-analysis of previous studies confirmed SVZ involvement (odds ratio [OR]: 1.30 [1.01–1.67]) and O-6-methylguanine DNA methyltransferase promoter methylation (OR: 1.55 [1.09–2.20]) as significant risk factors for local recurrence. A time-dependent meta-analysis revealed a significant association between SVZ involvement and dissemination (HR: 1.69 [1.09–2.63]), while no significant association was found for distant recurrence (HR: 1.29 [0.74–2.27]). Understanding SVZ involvement and specific tumor locations associated with non-local recurrence provides critical insights for the management of GBM. [ABSTRACT FROM AUTHOR]

Simple Summary: The Aerococcus viridans bacterial lactate oxidase (LOX) is an enzyme absent in mammalian cells. LOX catalyzes lactate to pyruvate and hydrogen peroxide (H2O2), a function that was recently used for tumor microenvironment (TME) lactate removal and H2O2 production to induce cancer cell death. However, the functions of TME lactate other than being a metabolic intermediate or an energy source and the mechanism of LOX disruption of lactate-mediated cancer cell survival remain unknown. Our study aims at addressing these important cancer-related biological questions. We identified a novel onco-signaling nexus initiated by TME lactate activation of its cellular receptor hydroxycarboxylic acid receptor 1 (HCAR1) and amplified by HCAR-associated proteins that mediate the RAS and the PI3K pathways. This signaling model could explain many key survival strategies exerted by RAS, PI3K, and their effectors for cancer cell adaptation to TME changes, especially in the cells' use of lactate beyond an energy source. LOX was recently shown to inhibit cancer cell proliferation and tumor growth. The mechanism of this inhibition, however, has been exclusively attributed to LOX depletion of TME lactate, a cancer cell energy source, and production of H2O2, an oxidative stressor. We report that TME lactate triggers the assembly of the lactate receptor hydroxycarboxylic acid receptor 1 (HCAR1)-associated protein complex, which includes GRB2, SOS1, KRAS, GAB1, and PI3K, for the activation of both the RAS and the PI3K oncogenic signaling pathways in breast cancer (BCa) cells. LOX treatment decreased the levels of the proteins in the protein complex via induction of their proteasomal degradation. In addition, LOX inhibited lactate-stimulated expression of the lactate transporters MCT1 and MCT4. Our data suggest that HCAR1 activation by lactate is crucial for the assembly and function of the RAS and PI3K signaling nexus. Shutting down lactate signaling by disrupting this nexus could be detrimental to cancer cells. HCAR1 is therefore a promising target for the control of the RAS and the PI3K signaling required for BCa progression. Thus, our study provides insights into lactate signaling regulation of cancer progression and extends our understanding of LOX's functional mechanisms that are fundamental for exploring its therapeutic potential. [ABSTRACT FROM AUTHOR]

The ever-increasing presence of micropollutants necessitates the development of environmentally friendly bioremediation strategies. Inspired by the remarkable versatility and potent catalytic activities of microbial enzymes, researchers are exploring their application as biocatalysts for innovative environmental cleanup solutions. Microbial enzymes offer remarkable substrate specificity, biodegradability, and the capacity to degrade a wide array of pollutants, positioning them as powerful tools for bioremediation. However, practical applications are often hindered by limitations in enzyme stability and reusability. Enzyme immobilization techniques have emerged as transformative strategies, enhancing enzyme stability and reusability by anchoring them onto inert or activated supports. These improvements lead to more efficient pollutant degradation and cost-effective bioremediation processes. This review delves into the diverse immobilization methods, showcasing their success in degrading various environmental pollutants, including pharmaceuticals, dyes, pesticides, microplastics, and industrial chemicals. By highlighting the transformative potential of microbial immobilized enzyme biocatalysts, this review underscores their significance in achieving a cleaner and more sustainable future through the mitigation of micropollutant contamination. Additionally, future research directions in areas such as enzyme engineering and machine learning hold immense promise for further broadening the capabilities and optimizing the applications of immobilized enzymes in environmental cleanup. [ABSTRACT FROM AUTHOR]

Purpose Pharmacogenetic testing can identify patients who may benefit from personalized drug treatment. However, clinical uptake of pharmacogenetic testing has been limited. Clinical practice guidelines recommend biomarker tests that the guideline authors deem to have demonstrated clinical utility, meaning that testing improves treatment outcomes. The objective of this narrative review is to describe the current status of pharmacogenetic testing recommendations within clinical practice guidelines in the US. Summary Guidelines were reviewed for pharmacogenetic testing recommendations for 21 gene-drug pairs that have well-established drug response associations and all of which are categorized as clinically actionable by the Clinical Pharmacogenetics Implementation Consortium. The degree of consistency within and between organizations in pharmacogenetic testing recommendations was assessed. Relatively few clinical practice guidelines that provide a pharmacogenetic testing recommendation were identified. Testing recommendations for HLA-B*57:01 before initiation of abacavir and G6PD before initiation of rasburicase, both of which are included in drug labeling, were mostly consistent across guidelines. Gene-drug pairs with at least one clinical practice guideline recommending testing or stating that testing could be considered included CYP2C19 -clopidogrel, CYP2D6 -codeine, CYP2D6 -tramadol, CYP2B6 -efavirenz, TPMT -thiopurines, and NUDT15 -thiopurines. Testing recommendations for the same gene-drug pair were often inconsistent between organizations and sometimes inconsistent between different guidelines from the same organization. Conclusion A standardized approach to evaluating the evidence of clinical utility for pharmacogenetic testing may increase the inclusion and consistency of pharmacogenetic testing recommendations in clinical practice guidelines, which could benefit patients and society by increasing clinical use of pharmacogenetic testing. [ABSTRACT FROM AUTHOR]

BACKGROUND: Currently, many emerging polycyclic aromatic hydrocarbons (PAHs) have been found to be widely present in the environment. However, little has been reported about their toxicity, particularly in relation to CYP1A1. OBJECTIVES: This study aimed to explore the toxicity of naphtho[2,1-a]pyrene (N21aP) and elucidate the mechanism underlying N21aP-induced expression of CYP1A1. METHODS: The concentration and sources of N21aP were detected and analyzed by gas chromatography–triple quadrupole mass spectrometry (GC-MS/ MS) and diagnostic ratio analysis. Then the effects of CYP1A1 on the toxicity of N21aP were conducted in male wild-type (WT) and Cyp1a1 knockout mice exposed to N21aP (0.02, 0.2, and 2 mg/kg) through intratracheal instillation. Further, the aryl hydrocarbon receptor (AhR) pathway was examined through luciferase and chromatin immunoprecipitation (ChIP) assays. 푁6-methyladenosine (m6A) modification levels were measured on global RNA and specifically on CYP1A1 mRNA using dot blotting and methylated RNA immunoprecipitation-quantitative real-time polymerase chain reaction (MeRIP qRT-PCR), with validation by m6A inhibitors, DAA and SAH. m6A sites on CYP1A1 were identified by bioinformatics and luciferase assays, and CYP1A1mRNA’s interaction with IGF2BP3 was confirmed by RNA pull-down, luciferase, and RNA binding protein immunoprecipitation (RIP) assays. RESULTS: N21aP was of the same environmental origin as benzo[a]pyrene (BaP) but was more stably present in the environment. N21aP could be metabolically activated by CYP1A1 to produce epoxides, causing DNA damage and further leading to lung inflammation. Importantly, in addition to the classical AhR pathway (i.e., BaP), N21aP also induced CYP1A1 expression with a posttranscriptional modification of m6A in CYP1A1 mRNA via the METTL14–IGF2BP3–CYP1A1 axis. Specifically, in the two recognition sites of METTL14 on the CYP1A1 mRNA transcript (position at 2700 and 5218), a methylation site (position at 5218) in the 3′-untranslated region (UTR) was recognized by IGF2BP3, enhanced the stability of CYP1A1 mRNA, and finally resulted in an increase in CYP1A1 expression. DISCUSSION: This study systematically demonstrated that in addition to AhR-mediated transcriptional regulation, N21aP, had a new additional mechanism of m6A-mediated posttranscriptional modification, jointly contributing to CYP1A1 expression. Given that PAHs are the metabolic substrates of CYP1A1, this study not only helps to understand the significance of environment–genetic interactions for the toxicity of PAHs but also helps to better understand the health risks of the emerging PAHs at environmental exposure levels. [ABSTRACT FROM AUTHOR]

Background: While folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes. Methods: This multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment. Results: The intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0–1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2–1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering. Conclusions: This randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg. ClinicalTrials.gov Identifier: NCT03472508 (Registration Date: March 21, 2018). [ABSTRACT FROM AUTHOR]

The high concentration of active substances in tomato extraction is correlated with its anti-tyrosinase and antioxidant effect activity. We established the optimum ultrasound extraction conditions for maximizing the yield of active substances. The four important factors (ethanol concentration, extraction time, extraction temperature, and solid-liquid ratio) that greatly affected ultrasonic extraction were selected to set up a single-factor test and investigate the effects of inhibitory activity on tyrosinase. According to the result of the single-factor test, the orthogonal experiment was conducted to select the optimum process parameter of extracting a total active substance from tomatoes by the alcohol extraction method. The factors affecting the extraction of active substances from tomatoes by an ultrasonic assistant method in order were as follows: ethanol concentration > solid-liquid ratio > extraction temperature > extraction time. The optimum process condition from the orthogonal experiment was as follows: ethanol concentration of 80%, solid-liquid ratio of 1:6, extraction temperature of 50°C, and extraction time of 50 min, under which the average anti-tyrosinase activity of active substances was 32.77% through the tyrosinase inhibition assay. [ABSTRACT FROM AUTHOR]

• Folate and glutathione (GSH) increased after tumor resection in hepatocellular carcinoma (HCC). • Vascular endothelial growth factor (VEGF) showed a decreased trend during follow-up in HCC. • VEGF correlates with folate, GSH, and GSH-related antioxidant enzymes in HCC. • The pre-resection VEGF level is a potential independent marker to predict HCC recurrence. The associations of tumor angiogenesis with folate and antioxidant capacities in patients with hepatocellular carcinoma (HCC) and their effects on HCC recurrence have not yet been investigated. We investigated the changes and relationships of VEGF, folate, GSH, and GSH-related antioxidant enzymes in patients with HCC before tumor resection, as well as 1 month, 1 year, and 3 years after tumor resection, and their effects on HCC recurrence. 95 HCC patients who underwent tumor resection were recruited. Patients were followed up before tumor resection (pre-resection), 1 month after tumor resection (post-resection), 1 year, and 3 years of follow-up. The recurrence and survival status of patients were evaluated. Plasma VEGF concentrations decreased slightly during follow-up. Serum folate and GSH concentrations and plasma GPx and GR activities increased significantly from pre-resection to post-resection and remained stable at follow-up. Pre-resection plasma VEGF was positively correlated with GSH, GPx, and GR, but negatively correlated with folate and GST. The high pre-resection plasma VEGF was a significant predictor of a high HCC rate (hazard ratio = 1.05, p = 0.035), remaining significant after adjustments for folate, GSH, GPx, GR, and GST to diminish their interference with VEGF. Pre-tumor-resection plasma VEGF constitutes a potential independent marker for predicting HCC recurrence. However, the associations of plasma VEGF with folate and GSH-related antioxidant capacities in HCC patients cannot be ignored. This study followed 95 patients with HCC who underwent tumor resection. VEGF decreased slightly during follow-up. Folate, GSH, GPx, and GR increased significantly after tumor resection and remained steady. Pre-resection VEGF correlated with folate, GSH, GPx, and GR. High pre-resection VEGF levels independently predicted a high HCC recurrence rate. HCC, hepatocellular carcinoma; VEGF, vascular endothelial growth factor; GSH, glutathione; GPx, glutathione peroxidase; GR, glutathione reductase. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: Oxylipins are bioactive lipids derived from polyunsaturated fatty acids (PUFAs) that modulate inflammation and may remain overexpressed in refractory synovitis. In plasma, they could also be biomarkers of synovial pathology. The aim of this study is to determine if synovial oxylipins in inflamed joints correlate with plasma oxylipins and with synovial histologic patterns. Methods: Patients with established rheumatoid or psoriatic arthritis with active disease despite treatment were recruited, and paired synovial tissue (ST) and plasma were collected. Oxylipins were determined by liquid chromatography with tandem mass spectrometry and were classified into groups according to their PUFA precursor and enzyme. The expression of CD20, CD68, CD3, and CD138 was obtained to describe synovial histology. Cell‐specific expression of oxylipin‐related genes was identified by examining available synovial single‐cell RNA sequencing data. Results: We included a total of 32 ST and 26 paired‐plasma samples. A total of 71 oxylipins were identified in ST, but only 24 were identified in plasma. Only levels of 9,10‐dihydroxyoctadecenoic acid and tetranor‐Prostaglandin FM had a significant positive correlation between plasma and ST. Several oxylipins and oxylipin‐related genes were differentially expressed among synovial phenotypes. Specifically, several 5‐lipoxygenase (LOX)–derived oxylipins were statistically elevated in the lympho‐myeloid phenotype and associated with B cell expression in rheumatoid arthritis samples. Conclusion: The lack of correlation between ST and plasma oxylipins suggests that ST lipid profiling better characterizes active pathways in treated joints. Synovial 5‐LOX–derived oxylipins were highly expressed in lympho‐myeloid–enriched synovium. Combination therapy with 5‐LOX inhibitors to improve refractory inflammation may be needed in patients with this histologic group. [ABSTRACT FROM AUTHOR]

Introduction: Hashimoto's thyroiditis (HT) is one of the most common autoimmune endocrine disorders in the pediatric age group. In this study, it was aimed to retrospectively examine our cases, who were children and adolescents diagnosed with HT. Materials and Methods: We retrospectively examined 119 patients between the ages of 1 and 18, who were diagnosed with HT. In all of the cases, physical examination findings, thyroid function tests, anti-thyroid peroxidase (anti-TPO) and antithyroglobulin (Anti-Tg) antibodies, thyroid ultrasonographies and accompanying autoimmune diseases were evaluated. Results: The female/male ratio was 3.5/1. In our cases, the median age at the time of diagnosis was 12.29 years and 10 (8.4%) of the cases were under the age of five. At the time of diagnosis, 37% of the cases were euthyroid, 21.8% had overt hypothyroidism, 34.5% had subclinical hypothyroidism, 2.5% had subclinical hyperthyroidism and 4.2% had overt hyperthyroidism. At the time of diagnosis, 102 cases (85.7%) had anti-TPO and 82 cases (68.9%) had anti-Tg positivity. The Anti-TPO levels at the time of admission were found to be significantly higher in the hypothyroid group compared to the euthyroid group. Conclusion: Thyroid function test results of patients with Hashimoto's thyroiditis may vary in the follow-up period. Even though most cases with euthyroidism remain euthyroid, some might progress to hypothyroidism. Although Hashimoto's thyroiditis is most frequently seen in adolescents, approximately 10% of the cases are under the age of five. Therefore, autoimmune thyroiditis should be considered in hypothyroidism occurring in the early stages of life. [ABSTRACT FROM AUTHOR]

Redox-based protein posttranslational modifications, such as S-nitrosylation of critical, active site cysteine thiols have garnered significant clinical attention and research interest, reasoning for one of the crucial biological implications of reactive messenger molecule, nitric oxide in the cellular repertoire. The stringency of the S-(de)nitrosylation-based redox switch governs the activity and contribution of several susceptible enzymes in signal transduction processes and diverse pathophysiological settings, thus establishing it as a transient yet reasonable, and regulated mechanism of NO adduction and release. Notably, endogenous proteases like cytosolic and mitochondrial caspases with a molecular weight ranging from 33 to 55 kDa are susceptible to performing this biochemistry in the presence of major oxidoreductases, which further unveils the enormous redox-mediated regulational control of caspases in the etiology of diseases. In addition to advancing the progress of the current state of understanding of 'redox biochemistry' in the field of medicine and enriching the existing dynamic S-nitrosoproteome, this review stands as a testament to an unprecedented shift in the underpinnings for redundancy and redox relay between the major redoxin/antioxidant systems, fine-tuning of which can command the apoptotic control of caspases at the face of nitro-oxidative stress. These intricate functional overlaps and cellular backups, supported rationally by kinetically favorable reaction mechanisms suggest the physiological relevance of identifying and involving such cognate substrates for cellular S-denitrosylases that can shed light on the bigger picture of extensively proposing targeted therapies and redox-based drug designing to potentially alleviate the side effects of NOx/ROS in disease pathogenesis. [ABSTRACT FROM AUTHOR]

Voriconazole is the first‐line treatment for invasive aspergillosis. Its pharmacokinetics exhibit considerable inter‐ and intra‐individual variability. The purpose of this study was to investigate the effects of CYP2C19, CYP2C9, CYP3A4, and FMO3 genetic polymorphisms and sex on the pharmacokinetics of voriconazole in healthy Chinese adults receiving single‐dose and multiple‐dose voriconazole, to provide a reference for its clinical individualized treatment. A total of 123 healthy adults were enrolled in the study, with 108 individuals and 15 individuals in the single‐dose and multiple‐dose doses, respectively. Plasma voriconazole concentrations were measured using a validated LC‐MS/MS method, and pharmacokinetics parameters were calculated using the non‐compartmental method with WinNonlin 8.2. CYP2C19, CYP2C9, CYP3A4, and FMO3 single‐nucleotide polymorphisms were sequenced using the Illumina Hiseq X‐Ten platform. The results suggested that CYP2C19 genetic polymorphisms significantly affected the pharmacokinetics of voriconazole at single doses of 4, 6, and 8 mg/kg and multiple doses of voriconazole. CYP3A4 rs2242480 had a significant effect on AUC0‐∞ (area under the plasma concentration‐time curve from time 0 to infinity) and MRT (mean residence time) of voriconazole at a single dose of 4 mg/kg in CYP2C19 extensive metabolizer. Regardless of the CYP2C19 genotype, CYP2C9 rs1057910 and FMO3 rs2266780 were not associated with the pharmacokinetics of voriconazole at three single‐dose levels or multiple doses. No significant differences in most voriconazole pharmacokinetics parameters were noted between male and female participants after single and multiple dosing. For patients receiving voriconazole treatment, CYP2C19 genetic polymorphisms should be genotyped for its precision administration. In contrast, based on our study of healthy Chinese adults, it seems unnecessary to consider the effects of CYP2C9, CYP3A4, and FMO3 genetic polymorphisms on voriconazole pharmacokinetics. [ABSTRACT FROM AUTHOR]

BI 187004, a selective small‐molecule inhibitor of 11β‐hydroxysteroid dehydrogenase‐1 (11β‐HSD1), displayed complex nonlinear pharmacokinetics (PK) in humans. Following nine single oral doses, BI 187004 exhibited nonlinear PK at low doses and linear PK at higher doses. Notably, substantial hepatic 11β‐HSD1 inhibition (50%) was detected in a very low‐dose group, achieving a consistent 70% hepatic enzyme inhibition in subsequent ascending doses without any dose‐dependent effects. The unusual PK and PD profiles of BI 187004 suggest the presence of pharmacological target‐mediated drug disposition (TMDD), arising from the saturable binding of BI 187004 compound to its high‐affinity and low‐capacity target 11β‐HSD1. The non‐intuitive dose, exposure, and response relationship for BI 187004 pose a significant challenge in rational dose selection. This study aimed to construct a TMDD model to explain the complex nonlinear PK behavior and underscore the importance of recognizing TMDD in this small‐molecule compound. Among the various models explored, the best model was a two‐compartment TMDD model with three transit absorption components. The final model provides insights into 11β‐HSD1 binding‐related parameters for BI 187004, including the total amount of 11β‐HSD1 in the liver (estimated to be 8000 nmol), the second order association rate constant (estimated to be 0.102 nM−1h−1), and the first‐order dissociation rate constant (estimated to be 0.11 h−1). Our final population PK model successfully characterized the intricate nonlinear PK of BI 187004 across a wide dose range. This modeling work serves as a valuable reference for the rational selection of the dose regimens for BI 187004's future clinical trials. [ABSTRACT FROM AUTHOR]

Excessive inflammatory response and oxidative stress (OS) play an important role in the pathogenesis of spinal cord injury (SCI). Balance of inflammation and prevention of OS have been considered an effective strategy for the treatment of SCI. Hyaluronan and proteoglycan link protein 1 (HAPLN1), also known as cartilage link protein, has displayed a wide range of biological and physiological functions in different types of tissues and cells. However, whether HAPLN1 regulates inflammation and OS during SCI is unknown. Therefore, we aimed to examine whether HAPLN1 can have a protective effect on SCI. In this study, both in vitro and in vivo SCI models were established. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays were used. Western blotting and enzyme‐linked immunosorbent assay were employed to assess the expression of proteins. Our results demonstrate that the administration of HAPLN1 promoted the recovery of motor neurons after SCI by increasing the Basso mouse scale score, increasing the numbers of motor neurons, and preventing apoptosis of spinal cord cells. Additionally, HAPLN1 mitigated OS in spinal cord tissue after SCI by increasing the content of superoxide dismutase SOD and the activity of glutathione peroxidase but reducing the levels of malondialdehyde. Importantly, we found that HAPLN1 stimulated the activation of the nuclear factor erythroid 2‐related factor 2 (Nrf2)/antioxidant response element (ARE) pathway and stimulated the expression of heme oxygenase‐1 and nicotinamide adenine dinucleotide phosphate quinone oxidoreductase‐1, which mediated the attenuation of HAPLN1 in activation of the NOD‐like receptor protein 3 (NLRP3) inflammasome by reducing the levels of NLRP3, apoptosis‐associated speck‐like protein containing a caspase recruitment domain (ASC), caspase‐1, and interleukin‐1β. Correspondingly, in vitro experiments show that the presence of HAPLN1 suppressed the NLRP3 inflammasome and prevented cell injury against H2O2 in PC12 cells. These effects were mediated by the Nrf2/ARE pathway, and inhibition of Nrf2 with ML385 abolished the beneficial effects of HAPLN1. Based on these findings, we conclude that HAPLN1 inhibits the NLRP3 inflammasome through the stimulation of the Nrf2/ARE pathway, thereby suppressing neuroinflammation, enhancing motor neuronal survival, and improving the recovery of nerve function after SCI. [ABSTRACT FROM AUTHOR]

Simple Summary: Isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) are essential metabolic enzymes involved in the tricarboxylic acid (TCA) cycle. Several mutations in IDH genes have recently been described in many solid tumors, including glioma, cholangiocarcinoma, and chondrosarcoma. These mutations lead to neomorphic enzymatic activity affecting cancer pathogenesis. This review aims to summarize the diagnostic and prognostic role of IDH mutations and to provide an overview of the actual IDH inhibitor-based therapies used in various solid malignancies, outlining the findings of the most recent clinical trials and searching for future perspectives. The isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) enzymes are involved in key metabolic processes in human cells, regulating differentiation, proliferation, and oxidative damage response. IDH mutations have been associated with tumor development and progression in various solid tumors such as glioma, cholangiocarcinoma, chondrosarcoma, and other tumor types and have become crucial markers in molecular classification and prognostic assessment. The intratumoral and serum levels of D-2-hydroxyglutarate (D-2-HG) could serve as diagnostic biomarkers for identifying IDH mutant (IDHmut) tumors. As a result, an increasing number of clinical trials are evaluating targeted treatments for IDH1/IDH2 mutations. Recent studies have shown that the focus of these new therapeutic strategies is not only the neomorphic activity of the IDHmut enzymes but also the epigenetic shift induced by IDH mutations and the potential role of combination treatments. Here, we provide an overview of the current knowledge about IDH mutations in solid tumors, with a particular focus on available IDH-targeted treatments and emerging results from clinical trials aiming to explore IDHmut tumor-specific features and to identify the clinical benefit of IDH-targeted therapies and their combination strategies. An insight into future perspectives and the emerging roles of circulating biomarkers and radiomic features is also included. [ABSTRACT FROM AUTHOR]

Simple Summary: The connection between neurodegenerative diseases (NDs) and cancer has sparked a growing interest in biomedical research. Cancer cells show alterations in proteins linked to ND (tau, amyloid-β, α-synuclein, SOD1, and TDP-43). This review offers an updated summary of the biological role of these proteins in cancer. Specifically, we explore the effects of these proteins on cancer biology and how they affect these processes. Finally, we address the challenges and opportunities of targeting these proteins in the development of new cancer treatments. The link between neurodegenerative diseases (NDs) and cancer has generated greater interest in biomedical research, with decades of global studies investigating neurodegenerative biomarkers in cancer to better understand possible connections. Tau, amyloid-β, α-synuclein, SOD1, TDP-43, and other proteins associated with nervous system diseases have also been identified in various types of solid and malignant tumors, suggesting a potential overlap in pathological processes. In this review, we aim to provide an overview of current evidence on the role of these proteins in cancer, specifically examining their effects on cell proliferation, apoptosis, chemoresistance, and tumor progression. Additionally, we discuss the diagnostic and therapeutic implications of this interconnection, emphasizing the importance of further research to completely comprehend the clinical implications of these proteins in tumors. Finally, we explore the challenges and opportunities in targeting these proteins for the development of new targeted anticancer therapies, providing insight into how to integrate knowledge of NDs in oncology research. [ABSTRACT FROM AUTHOR]

Simple Summary: Acute myeloid leukemia (AML) arises from a stepwise acquisition of multiple genetic alterations in the hematopoietic stem and progenitor cell and is characterized by an accumulation of immature leukemic cells, called blasts, in the bone marrow and tissues. How the single gene alterations mediate the underlying processes is unclear in the majority of cases. IDH1/2 mutations are among the most frequent mutations in AML, accounting for about 15–20%, and are targets of specific small molecule inhibitors. Experimental evidence suggests that they occur early in leukemogenesis. Mostly, murine models of IDH1/2 mutations have been studied. Our study is the first to highlight that—in the human system—IDH1/2 mutants drive a complete block of hematopoietic cell differentiation in vitro, which is completely unleashed by the specific inhibitor, providing a model for early leukemogenesis studies in this setting. How hematopoietic stem and progenitor cell (HSPC) fate decisions are affected by genetic alterations acquired during AML leukemogenesis is poorly understood and mainly explored in animal models. Here, we study isocitrate dehydrogenase (IDH) gene mutations in the human model of HSPC and discuss the available literature on this topic. IDH1/2 mutations occur in ~20% of AML cases, are recognized among the mutations earliest acquired during leukemogenesis, and are targets of specific inhibitors (ivosidenib and enasidenib, respectively). In order to investigate the direct effects of these mutations on HSPCs, we expressed IDH1-R132H or IDH2-R140Q mutants into human CD34+ healthy donor cells via lentiviral transduction and analyzed the colony-forming unit (CFU) ability. CFU ability was dramatically compromised with a complete trilineage block of differentiation. Strikingly, the block was reversed by specific inhibitors, confirming that it was a specific effect induced by the mutants. In line with this observation, the CD34+ leukemic precursors isolated from a patient with IDH2-mutated AML at baseline and during enasidenib treatment showed progressive and marked improvements in their fitness over time, in terms of CFU ability and propensity to differentiate. They attained clonal trilinear reconstitution of hematopoiesis and complete hematological remission. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae (Kp) is an infectious disease pathogen that poses a significant global health threat due to its potential to cause severe infections and its tendency to exhibit multidrug resistance. Understanding the enzymatic mechanisms of the oxygen‐insensitive nitroreductases (Kp‐NRs) from Kp is crucial for the development of effective nitrofuran drugs, such as nitrofurantoin, that can be activated as antibiotics. In this paper, three crystal structures of two Kp‐NRs (PDB entries 7tmf/7tmg and 8dor) are presented, and an analysis of their crystal structures and their flavin mononucleotide (FMN)‐binding mode is provided. The structures with PDB codes 7tmf (Kp‐NR1a), 7tmg (Kp‐NR1b) and 8dor (Kp‐NR2) were determined at resolutions of 1.97, 1.90 and 1.35 Å, respectively. The Kp‐NR1a and Kp‐NR1b structures adopt an αβ fold, in which four‐stranded antiparallel β‐sheets are surrounded by five helices. With domain swapping, the β‐sheet was expanded with a β‐strand from the other molecule of the dimer. The difference between the structures lies in the loop spanning Leu173–Ala185: in Kp‐NR1a the loop is disordered, whereas the loop adopts multiple conformations in Kp‐NR1b. The FMN interactions within Kp‐NR1/NR2 involve hydrogen‐bond and π‐stacking interactions. Kp‐NR2 contains four‐stranded antiparallel β‐sheets surrounded by eight helices with two short helices and one β‐sheet. Structural and sequence alignments show that Kp‐NR1a/b and Kp‐NR2 are homologs of the Escherichia coli oxygen‐insensitive NRs YdjA and NfnB and of Enterobacter cloacae NR, respectively. By homology inference from E. coli, Kp‐NR1a/b and Kp‐NR2 may detoxify polynitroaromatic compounds and Kp‐NR2 may activate nitrofuran drugs to cause bactericidal activity through a ping‐pong bi‐bi mechanism, respectively. [ABSTRACT FROM AUTHOR]

Background and Objective: The biological effects of atmospheric plasma (cold plasma) show its applicability for controlling the etiological factors that involve tissue repair. Thus, the study evaluated the effect of atmospheric plasma therapy in the control of tissue inflammation and bone remodeling in experimental periodontitis. Methods: Fifty‐six rats were subjected to ligation in the cervical region of the first maxillary molars (8 weeks). The animals were divided into two groups (n = 28): periodontitis without treatment group (P group), and periodontitis with atmospheric plasma treatment group (P + AP group). Tissue samples were collected at 2 and 4 weeks after treatment to analyze the inflammation and bone remodeling by biochemical, histomorphometric, and immunohistochemical analyses. Results: Inflammatory infiltration in the gingival and periodontal ligament was lower in the P + AP group than in the P group (p <.05). The MPO and NAG levels were higher in the P + AP group compared to P group (p <.05). At 4 weeks, the TNF‐α level was lower and the IL‐10 level was higher in the P + AP group compared to P group (p <.05). In the P + AP group, the IL‐1β level increased in the second week and decreased in the fourth week (p <.05), the number of blood vessels was high in the gingival and periodontal ligament in the second and fourth week (p <.05); and the number of fibroblasts in the gingival tissue was low in the fourth week, and higher in the periodontal tissue in both period (p <.05). Regarding bone remodeling, the RANK and RANKL levels decreased in the P + AP group (p <.05). The OPG level did not differ between the P and P + AP groups (p >.05), but decreased from the second to the fourth experimental week in P + AP group (p <.05). Conclusions: The treatment of experimental periodontitis with atmospheric plasma for 4 weeks modulated the inflammatory response to favor the repair process and decreased the bone resorption biomarkers, indicating a better control of bone remodeling in periodontal disease. [ABSTRACT FROM AUTHOR]

Primary pediatric neurotransmitter disorders include genetic defects of neurotransmitter metabolism that may mimic common neurological conditions in children. Our objective was to evaluate the clinical experience and outcomes of affected patients. Five patients with primary neurotransmitter defects were identified in the neurometabolic database between 2004 and 2022. Two patients with 6-pyruvoyltetrahydropterin synthase deficiency and one with pyridoxine-dependent epilepsy (PDE) presented in the neonatal period. One patient with succinic semialdehyde dehydrogenase (SSADH) deficiency and one with aromatic l-amino acid decarboxylase (AADC) deficiency presented in later life. A diagnosis of cerebral palsy was revised following biochemical confirmation of SSADH deficiency. AADC deficiency was confirmed via exome sequencing and reduced activity on enzyme assay. Late diagnosis in the latter two cases was likely due to a low index of suspicion and lack of access to diagnostic tests in the country of origin. In two children with tetrahydrobiopterin deficiency, newborn screening results and atypical clinical features prompted investigations. An early diagnosis of PDE was established based on presenting features, a high index of suspicion, the presence of an identifiable biochemical marker and molecular genetic testing. Pediatric neurotransmitter disorders can be diagnosed based on a high clinical index of suspicion, availability of biochemical markers, and molecular genetic testing. These disorders, though rare, need to be included in the differential diagnosis of common neurological presentations in children as they may be potentially treatable. Outcomes and influencing factors in the present series are discussed in comparison to published data. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) presents significant challenges in pediatric care, often remaining underrecognized. This paper provides an overview of pediatric AKI, highlighting its epidemiology, pathophysiology, diagnosis, predisposing conditions, and treatment. AKI in children stems from diverse causes, including renal tubular damage, vasoconstriction, and inflammation. Diagnosis relies on traditional markers such as serum creatinine and urine output, alongside emerging biomarkers such as Cystatin C, NGAL, KIM-1, IL-18, TIMP-2 and IGFBP7, urinary calprotectin, URBP4, L-FABP, and clusterin. Various pediatric conditions predispose to AKI, including type 1 diabetes, pneumonia, bronchiolitis, appendicitis, gastroenteritis, COVID-19, multisystem inflammatory syndrome, sickle cell disease, and malignancies. Treatment entails supportive care with fluid management and, in severe cases, renal replacement therapy. Timely recognition and management are essential to mitigating adverse outcomes. Enhanced awareness and integration of novel biomarkers could improve pediatric AKI care, warranting further research for better diagnosis and management. [ABSTRACT FROM AUTHOR]

Background Isocitrate dehydrogenase 1 (IDH1) missense mutations occur at a frequency of 10%-15% in intrahepatic cholangiocarcinoma (iCCA). IDH1 mutations result in accumulation of (R)-2-hydroxyglutarate, an oncometabolite that leads to DNA hypermethylation and impairment of homologous recombination (HR). Impairment of HR results in a "BRCAness" phenotype which may confer sensitivity to poly(ADP ribose) polymerase (PARP) inhibition. Methods We conducted a retrospective cohort review to identify patients with advanced, IDH1 mutated iCCA treated with a PARP inhibitor (PARPi) at the University of Michigan between 2018 and 2023. Patients are described with respect to prior lines of therapy, response to platinum-based chemotherapy, and progression-free survival (PFS) and overall survival (OS) from the time of PARPi initiation. Results Between 2018 and 2023 we identified 40 patients with IDH1 mutated iCCA of which 6 patients were treated with a PARPi as monotherapy or in combination with an ATR inhibitor or anti-PD-1 immune checkpoint inhibitor. Majority of patients (n  = 5) carried an IDH1 R132C mutation per tissue-based next generation sequencing. All patients had previously received at least one line of cisplatin-based systemic therapy for advanced disease prior to treatment with PARPi. PFS and OS from time of PARPi initiation ranged from 1.4 to 18.5 months and 2.8 to 42.4 months, respectively. Best response on PARPi therapy included 2 partial responses. Conclusion This is the first case series to describe PARPi treatment in IDH1 mutated iCCA. Results underscore the limitation of PARPi monotherapy, potentially support combined PARPi therapies, and highlight a need for effective treatment options for patients with IDH1 mutated iCCA. [ABSTRACT FROM AUTHOR]

Background Patients with intrahepatic cholangiocarcinoma (ICC) are prone to recurrence and poor survival. Targeted therapy related to isocitrate dehydrogenase (IDH) is an extremely important treatment. IDH1 and IDH2 mutations are generally thought to have similar effects on the tumor landscape. However, it is doubtful whether these 2 mutations have exactly the same effects on tumor cells and the tumor microenvironment. Methods All collected tumor samples were subjected to simultaneous whole-exon sequencing and proteome sequencing. Results IDH1 mutations accounted for 12.2%, and IDH2 mutations accounted for 5.5%, all missense mutations. Tumors with IDH mutations had lower proportions of KRAS and TP53 mutations. Mutated genes were obviously enriched in the kinase pathway in the tumors with IDH2 mutations. The signaling pathways were mainly enriched in the activation of cellular metabolic activities and an increase of inhibitory immune cells in the tumors with IDH mutations. Moreover, tumors had unique enrichment in DNA repair in IDH1 mutants and secretion of biological molecules in IDH2 mutants. Inhibitory immune cells might be more prominent in IDH2 mutants, and the expression of immune checkpoints PVR and HLA-DQB1 was more prominent in IDH1 mutants. IDH mutants were more related to metabolism-related and inflammation-immune response clusters, and some belonged to the DNA replication and repair cluster. Conclusions These results revealed the differential IDH1 and IDH2 mutation-related landscapes, and we have provided an important reference database to guide ICC treatment. [ABSTRACT FROM AUTHOR]

Background/Objectives: Quantification of diamine oxidase (DAO) concentrations in serum has been proposed as an adjunctive diagnostic modality for the evaluation of histamine intolerance (HIT). Limited empirical data exist concerning the influence of dietary patterns on DAO levels. Subjects/Methods: In the context of a prospective study employing a crossover design, 18 individuals diagnosed with HIT were randomized to initiate either a low histamine diet (LHD) or a conventional mixed diet (MXD). Serum DAO concentrations were measured at the commencement of the study and following each dietary phase. A control group underwent analogous DAO assessments without imposition of dietary constraints. Results: During the time when a diet restricted in histamine was implemented, noticeable differences in changes in DAO levels did not become apparent when compared to the changes observed during the mixed (MXD) phase. Specifically, among the group, 10 of the 18 patients exhibited elevated DAO values subsequent to the LHD regimen, while the remaining eight displayed either reduced or unchanging DAO levels. The prevalence of elevated DAO levels in the LHD group did not differ significantly from that observed in the control group during the MXD phase. Additionally, during the LHD phase, patients reported a significant reduction in gastrointestinal and cutaneous symptoms. Conclusions: This prospective investigation underscores the enduring utility of a histamine-restricted diet, coupled with structured dietary reintroduction, as an efficacious diagnostic approach for individuals presenting with suspected food-related histamine hypersensitivity. Notably, the measurement of DAO levels appears to furnish only a limited capacity to discern dietary-induced fluctuations. Notwithstanding, the dynamics of DAO alteration do not appear to exhibit a discernible association with specific dietary patterns, a finding consistent across both patient and control groups. [ABSTRACT FROM AUTHOR]

Highlights: SPI1 and SMAD5 are upregulated during MC3T3-E1 cell osteogenic differentiation. SPI1 enhances SMAD5 transcription. Icariin increases SMAD5 expression by upregulating SPI1. The SPI1/SMAD5 axis underlies the promoting effect of icariin on MC3T3-E1 cell osteogenic differentiation. Background: Dysregulation of osteogenic differentiation is a crucial event during osteoporosis. The bioactive phytochemical icariin has become an anti-osteoporosis candidate. Here, we elucidated the mechanisms underlying the promoting function of icariin in osteogenic differentiation. Methods: Murine pre-osteoblast MC3T3-E1 cells were stimulated with dexamethasone (DEX) to induce osteogenic differentiation, which was evaluated by an Alizarin Red staining assay and ALP activity measurement. The mRNA amounts of SPI1 and SMAD5 were detected by real-time quantitative PCR. Expression analysis of proteins, including osteogenic markers (OPN, OCN and RUNX2) and autophagy-associated proteins (LC3, Beclin-1, and ATG5), was performed by immunoblotting. The binding of SPI1 and the SMAD5 promoter was predicted by the Jaspar2024 algorithm and confirmed by chromatin immunoprecipitation (ChIP) experiments. The regulation of SPI1 in SMAD5 was examined by luciferase assays. Results: During osteogenic differentiation of MC3T3-E1 cells, SPI1 and SMAD5 were upregulated. Functionally, SPI1 overexpression enhanced autophagy and osteogenic differentiation of MC3T3-E1 cells, while SMAD5 downregulation exhibited opposite effects. Mechanistically, SPI1 could enhance SMAD5 transcription and expression. Downregulation of SMAD5 also reversed SPI1 overexpression-induced autophagy and osteogenic differentiation in MC3T3-E1 cells. In MC3T3-E1 cells under DEX stimulation, icariin increased SMAD5 expression by upregulating SPI1. Furthermore, icariin could attenuate SPI1 depletion-imposed inhibition of autophagy and osteogenic differentiation of MC3T3-E1 cells. Conclusion: Our findings demonstrate that the SPI1/SMAD5 cascade, with the ability to enhance osteogenic differentiation, underlies the promoting effect of icariin on osteogenic differentiation of MC3T3-E1 cells. In dexamethasone-stimulated murine pre-osteoblast MC3T3-E1 cells, icariin upregulates SPI1 and thus enhances SMAD5 transcription, leading to enhanced autophagy and osteogenic differentiation of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

In nature, methylmercury (MeHg) is primarily generated through microbial metabolism, and the ability of bacteria to methylate Hg(II) depends on both bacterial properties and environmental factors. It is widely known that, as a metabolic analog, molybdate can inhibit the sulfate reduction process and affect the growth and methylation of sulfate-reducing bacteria (SRB). However, after it enters the cell, molybdate can be involved in various intracellular metabolic pathways as a molybdenum cofactor; whether fluctuations in its concentration affect the growth and methylation of aerobic mercury methylating strains remains unknown. To address this gap, aerobic γ-Proteobacteria strains Raoultella terrigena TGRB3 (B3) and Pseudomonas putida TGRB4 (B4), as well as an obligate anaerobic δ-Proteobacteria strain of the SRB Desulfomicrobium escambiense CGMCC 1.3481 (DE), were used as experimental strains. The growth and methylation ability of each strain were analyzed under conditions of 500 ng⋅L-1 Hg(II), 0 and 21% of oxygen, and 0, 0.25, 0.50, and 1 mM of MoO4 2-. In addition, in order to explore the metabolic specificity of aerobic strains, transcriptomic data of the facultative mercury-methylated strain B3 were further analyzed in an aerobic mercuric environment. The results indicated that: (a) molybdate significantly inhibited the growth of DE, while B3 and B4 exhibited normal growth. (b) Under anaerobic conditions, in DE, the MeHg content decreased significantly with increasing molybdate concentration, while in B3, MeHg production was unaffected. Furthermore, under aerobic conditions, the MeHg productions of B3 and B4 were not influenced by the molybdate concentration. (c) The transcriptomic analysis showed several genes that were annotated as members of the molybdenum oxidoreductase family of B3 and that exhibited significant differential expression. These findings suggest that the differential expression of molybdenum-binding proteins might be related to their involvement in energy metabolism pathways that utilize nitrate and dimethyl sulfoxide as electron acceptors. Aerobic bacteria, such as B3 and B4, might possess distinct Hg(II) biotransformation pathways from anaerobic SRB, rendering their growth and biomethylation abilities unaffected by molybdate. [ABSTRACT FROM AUTHOR]

Background: The progression of osteoporosis (OP) can dramatically increase the risk of fractures, which seriously disturb the life of elderly individuals. Specific protein 1 (SP1) is involved in OP progression. However, the mechanism by which SP1 regulates OP progression remains unclear. Objective: This study investigated the mechanism underlying the function of SP1 in OP. Methods: SAMP6 mice were used to establish an in vivo model of age-dependent OP, and BALB/c mice were used as controls. BMSCs were extracted from two subtypes of mice. Hematoxylin and eosin staining were performed to mark the intramedullary trabecular bone structure to evaluate histological changes. ChIP assay was used to assess the targeted regulation between SP1 and miR-133a-3p. The binding sites between MAPK3 and miR-133a-3p were verified using a dual-luciferase reporter assay. The mRNA levels of miR-133a-3p and MAPK3 were detected using quantitative reverse transcription polymerase chain reaction (RT-qPCR). The protein expression of SP1, MAPK3, Colla1, OCN, and Runx2 was examined using Western blotting. Alkaline phosphatase (ALP) kit and Alizarin Red S staining were used to investigate ALP activity and mineralized nodules, respectively. Results: The levels of SP1 and miR-133a-3p were upregulated, whereas the expression of MAPK3 was downregulated in BMSCs from SAMP6 mice, and miR-133a-3p inhibitor accelerated osteogenic differentiation in BMSCs. SP1 directly targeted miR-133a-3p, and MAPK3 was the downstream mRNA of miR-133a-3p. Mechanically, SP1 accelerated osteogenic differentiation in BMSCs via transcriptional mediation of the miR-133a-3p/MAPK3 axis. Conclusion: SP1 regulates osteogenic differentiation by mediating the miR-133a-3p/MAPK3 axis, which would shed new light on strategies for treating senile OP. [ABSTRACT FROM AUTHOR]

Formate oxidase (FOx), which contains 8-formyl flavin adenine dinucleotide (FAD), exhibits a distinct advantage in utilizing ambient oxygen molecules for the oxidation of formic acid compared to other glucose-methanol-choline (GMC) oxidoreductase enzymes that contain only the standard FAD cofactor. The FOx-mediated conversion of FAD to 8-formyl FAD results in an approximate 10-fold increase in formate oxidase activity. However, the mechanistic details underlying the autocatalytic formation of 8-formyl FAD are still not well understood, which impedes further utilization of FOx. In this study, we employ molecular dynamics simulation, QM/MM umbrella sampling simulation, enzyme activity assay, site-directed mutagenesis, and spectroscopic analysis to elucidate the oxidation mechanism of FAD to 8-formyl FAD. Our results reveal that a catalytic water molecule, rather than any catalytic amino acids, serves as a general base to deprotonate the C8 methyl group on FAD, thus facilitating the formation of a quinone-methide tautomer intermediate. An oxygen molecule subsequently oxidizes this intermediate, resulting in a C8 methyl hydroperoxide anion that is protonated and dissociated to form OHC-RP and OH−. During the oxidation of FAD to 8-formyl FAD, the energy barrier for the rate-limiting step is calculated to be 22.8 kcal/mol, which corresponds to the required 14-hour transformation time observed experimentally. Further, the elucidated oxidation mechanism reveals that the autocatalytic formation of 8-formyl FAD depends on the proximal arginine and serine residues, R87 and S94, respectively. Enzymatic activity assay validates that the mutation of R87 to lysine reduces the kcat value to 75% of the wild-type, while the mutation to histidine results in a complete loss of activity. Similarly, the mutant S94I also leads to the deactivation of enzyme. This dependency arises because the nucleophilic OH− group and the quinone-methide tautomer intermediate are stabilized through the noncovalent interaction provided by R87 and S94. These findings not only explain the mechanistic details of each reaction step but also clarify the functional role of R87 and S94 during the oxidative maturation of 8-formyl FAD, thereby providing crucial theoretical support for the development of novel flavoenzymes with enhanced redox properties. [ABSTRACT FROM AUTHOR]

Introduction. Antibody mediated rejection (AMR) is a major challenge in kidney transplantation and adversely affects allograft survival. Oxidative stress (OS) is implicated in AMR pathogenesis by triggering inflammation, apoptosis and fibrosis in the graft tissue. However, the status of OS and antioxidant defense in AMR patients remains unclear. We aimed to evaluate the levels of OS markers and antioxidant enzymes in AMR patients. Methods. We conducted a case-control study involving 22 biopsyproven AMR patients (test group) and 14 kidney recipients with stable graft function (control group). Serum total oxidant status (TOS), total antioxidant capacity (TAC), total thiol groups, nitric oxide (NO), 8-isoprostane (8-IP) were determined and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were measured by spectrophotometric methods. Results. Data analysis showed significant increases in TOS, TAC and 8-IP levels together with marked reductions in NO and total thiol groups in AMR patients. CAT and GPx activities did not differ between groups, however SOD activity was significantly lower in AMR patients. Conclusion. Our study showed increased OS and impaired antioxidant defense in AMR patients. NO level may serve as a potential biomarker of OS severity and immune response in AMR. Further studies are required to elucidate the mechanisms and consequences of OS in AMR and to explore the therapeutic potential of antioxidants. [ABSTRACT FROM AUTHOR]

Background: The methylenetetrahydrofolate reductase (MTHFR) gene is an essential gene in the metabolism of folate-homocysteine. Recently, the level of homocysteine was found to be a significant marker in the follow-up of COVID-19 infection. Thus, this study aimed to detect the effect of genetic polymorphisms for single nucleotide polymorphisms (SNPs) (c.66A>G, c.1298A>C, and c.677CT) on COVID-19 infection. Methods: Blood samples were collected from 270 patients with COVID-19 in the medical center of Al-Shifa (Baghdad, Iraq) from November 2020 to March 2021. Tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMSPCR) technique was used for the detection of genotypes of SNPs. The odds ratio (OR) was used to detect the relationship between SNPs and COVID-19 infections. Haplotype analysis was performed by SHEsis software. Results: There was a significant difference between mild/ moderate cases and severe/critical cases for ages (35-45), (46-55), and (56-65) years (P<0.0001, P=0.01, and P=0.006, respectively). The results showed significant differences in the T allele for SNP c.677>C (P<0.0001 and OR=4.58). The C allele for SNP c.1298A>C indicated significant differences (P<0.001 and OR=3.15). Besides, the G allele for SNP c.677C>T showed significant differences (P<0.001 and OR=6.64). Consequently, these SNPs showed a predisposition to the development of COVID-19 infection. With regard to the C-A-A, T-A-A and T-C-G haplotypes indicated significant differences between the control and patient groups. The C-A-A was related to a decreased risk and indicated a protective effect against COVID-19 infection development (P<0.0001 and OR=0.218). The increased risk was associated with T-A-A and T-C-G haplotypes and indicated the risk impact on COVID- 19 infection development (P<0.0001, P=0.004, and OR=15.5, OR=6.772, respectively). Furthermore, the linkage disequilibrium (LD) for SNPs was studied, and the complete D' value was 99%. Conclusion: The genetic polymorphisms of SNPs (c.66A>G, c.1298A>C, and c.677C>T) in the Iraqi population were associated with COVID-19 infection. [ABSTRACT FROM AUTHOR]