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The 2016 and 2021 World Health Organization 2021 Classification of central nervous system tumors have resulted in a major improvement in the classification of isocitrate dehydrogenase (IDH)-mutant gliomas. With more effective treatments many patients experience prolonged survival. However, treatment guidelines are often still based on information from historical series comprising both patients with IDH wild-type and IDH-mutant tumors. They provide recommendations for radiotherapy and chemotherapy for so-called high-risk patients, usually based on residual tumor after surgery and age over 40. More up-to-date studies give a better insight into clinical, radiological, and molecular factors associated with the outcome of patients with IDH-mutant glioma. These insights should be used today for risk stratification and for treatment decisions. In many patients with IDH-mutant grades 2 and 3 glioma, if carefully monitored postponing radiotherapy and chemotherapy is safe, and will not jeopardize the overall outcome of patients. With the INDIGO trial showing patient benefit from the IDH inhibitor vorasidenib, there is a sizable population in which it seems reasonable to try this class of agents before recommending radio-chemotherapy with its delayed adverse event profile affecting quality of survival. Ongoing trials should help to further identify the patients that are benefiting from this treatment.

N-myristoyltransferase (NMT) is a promising antimalarial drug target. Despite biochemical similarities between Plasmodium vivax and human NMTs, our recent research demonstrated that high selectivity is achievable. Herein, we report PvNMT-inhibiting compounds aimed at identifying novel mechanisms of selectivity. Various functional groups are appended to a pyrazole moiety in the inhibitor to target a pocket formed beneath the peptide binding cleft. The inhibitor core group polarity, lipophilicity, and size are also varied to probe the water structure near a channel. Selectivity index values range from 0.8 to 125.3. Cocrystal structures of two selective compounds, determined at 1.97 and 2.43 Å, show that extensions bind the targeted pocket but with different stabilities. A bulky naphthalene moiety introduced into the core binds next to instead of displacing protein-bound waters, causing a shift in the inhibitor position and expanding the binding site. Our structure-activity data provide a conceptual foundation for guiding future inhibitor optimizations.

The phase III double-blind PROPEL study compared the novel two-component therapy cipaglucosidase alfa + miglustat (cipa + mig) with alglucosidase alfa + placebo (alg + pbo) in adults with late-onset Pompe disease (LOPD). This ongoing open-label extension (OLE; NCT04138277) evaluates long-term safety and efficacy of cipa + mig. Outcomes include 6-min walk distance (6MWD), forced vital capacity (FVC), creatine kinase (CK) and hexose tetrasaccharide (Hex4) levels, patient-reported outcomes and safety. Data are reported as change from PROPEL baseline to OLE week 52 (104 weeks post-PROPEL baseline). Of 118 patients treated in the OLE, 81 continued cipa + mig treatment from PROPEL (cipa + mig group; 61 enzyme replacement therapy [ERT] experienced prior to PROPEL; 20 ERT naïve) and 37 switched from alg + pbo to cipa + mig (switch group; 29 ERT experienced; 8 ERT naive). Mean (standard deviation [SD]) change in % predicted 6MWD from baseline to week 104 was + 3.1 (8.1) for cipa + mig and - 0.5 (7.8) for the ERT-experienced switch group, and + 8.6 (8.6) for cipa + mig and + 8.9 (11.7) for the ERT-naïve switch group. Mean (SD) change in % predicted FVC was - 0.6 (7.5) for cipa + mig and - 3.8 (6.2) for the ERT-experienced switch group, and - 4.8 (6.5) and - 3.1 (6.7), respectively, in ERT-naïve patients. CK and Hex4 levels improved in both treatment groups by week 104 with cipa + mig treatment. Three patients discontinued the OLE due to infusion-associated reactions. No new safety signals were identified. Cipa + mig treatment up to 104 weeks was associated with overall maintained improvements (6MWD, biomarkers) or stabilization (FVC) from baseline with continued durability, and was well tolerated, supporting long-term benefits for patients with LOPD.Trial registration number: NCT04138277; trial start date: December 18, 2019.

In our efforts to develop inhibitors selective for neuronal nitric oxide synthase (nNOS) over endothelial nitric oxide synthase (eNOS), we found that nNOS can undergo conformational changes in response to inhibitor binding that does not readily occur in eNOS. One change involves movement of a conserved tyrosine, which hydrogen bonds to one of the heme propionates, but in the presence of an inhibitor, changes conformation, enabling part of the inhibitor to hydrogen bond with the heme propionate. This movement does not occur as readily in eNOS and may account for the reason why these inhibitors bind more tightly to nNOS. A second structural change occurs upon the binding of a second inhibitor molecule to nNOS, displacing the pterin cofactor. Binding of this second site inhibitor requires structural changes at the dimer interface, which also occurs more readily in nNOS than in eNOS. Here, we used a combination of crystallography, mutagenesis, and computational methods to better understand the structural basis for these differences in NOS inhibitor binding. Computational results show that a conserved tyrosine near the primary inhibitor binding site is anchored more tightly in eNOS than in nNOS, allowing for less flexibility of this residue. We also find that the inefficiency of eNOS to bind a second inhibitor molecule is likely due to the tighter dimer interface in eNOS compared with nNOS. This study provides a better understanding of how subtle structural differences in NOS isoforms can result in substantial dynamic differences that can be exploited in the development of isoform-selective inhibitors.

Alcohol Use Disorder (AUD) is a significant public health issue in the United States. It affects millions of individuals and their families and contributes to substantial societal and economic burdens. Despite the availability of some pharmacological treatments, there is still a pressing need to develop more effective therapeutic strategies to address the diverse range of symptoms and challenges associated with AUD. Catechol-O-methyltransferase (COMT) inhibition recently emerged as a promising new approach to treating AUD due to its potential to improve cognitive effects commonly associated with AUD. Tolcapone, an FDA-approved COMT inhibitor, has shown some promise for treating AUD; however, its ability to decrease drinking in ethanol-dependent rats has not been well-established. In this study, we evaluated the effects of tolcapone on operant, oral ethanol self-administration in non-dependent and dependent rats, and in rats that self-administered oral saccharin. To induce dependence, rats underwent the chronic intermittent exposure to vapor model, and their drinking levels were assessed during acute withdrawal from ethanol. Our results demonstrated that tolcapone attenuated responding for ethanol in dependent rats only, without affecting self-administration in non-dependent rats or rats self-administering saccharin. Moreover, we found that tolcapone was differentially effective in different estrous phases in female rats. These findings suggest that COMT inhibition, specifically using tolcapone, may be a valuable pharmacotherapy for treating AUD, particularly in individuals who are physically dependent on alcohol. Further research is needed to elucidate the precise mechanisms underlying the observed effects and to assess the potential of COMT inhibitors in a broader population of individuals with AUD.

Colorectal cancer (CRC) is one of the most common malignant tumors. Identification of new effective drug targets for CRC and exploration of bioactive small‐molecules are clinically urgent. The human dCTP pyrophosphatase 1 (DCTPP1) is a newly identified pyrophosphatase regulating the cellular nucleotide pool but remains unexplored as potential target for CRC treatment. Here, twelve unprecedented chemical architectures terpene‐nonadride heterodimers (1–12) and their monomers (13–20) were isolated from endophyte Bipolaris victoriae S27. Compounds 1–12 represented the first example of terpene‐nonadride heterodimers, in which nonadride monomers of 1 and 2 were also first example of 5/6 bicyclic nonadrides. A series of assays showed that 2 could repress proliferation and induce cell cycle arrest, apoptotic and autophagic CRC cell death in vitro and in vivo. Clinical cancer samples data revealed that DCTPP1 was a novel target associated with poor survival in CRC. DCTPP1 was also identified as a new target protein of 2. Mechanically, compound 2 bound to DCTPP1, inhibited its enzymatic activity, intervened with amino acid metabolic reprogramming, and exerted anti‐CRC activity. Our study demonstrates that DCTPP1 was a novel potential biomarker and therapeutic target for CRC, and 2 was the first natural anti‐CRC drug candidate targeting DCTPP1. [ABSTRACT FROM AUTHOR]

This study suggests that glial cells, specifically astrocytes, in discrete functional domains of the hippocampus play different roles in the processing of aversive and rewarding experiences. DH, dorsal hippocampus; IH, intermediate hippocampus; VH, ventral hippocampus; MWM, Morris water maze; TPP, T-maze place preference; PA, passive avoidance. [Display omitted] • The hippocampus long-axis is functionally organized for reward and aversion. • Astrocytes promote the functional distinction of the hippocampus long-axis. • Different functions of astrocytes in discrete functional domains of the hippocampus. This study aims to investigate whether glial cells, in particular putative astrocytes, contribute to functional distinctions between the dorsal (DH), intermediate (IH), and ventral (VH) hippocampus. To evaluate this, we performed three different behavioral tasks (i.e., Morris water maze; MWM, Passive avoidance; PA, T-maze place preference; TPP) to determine whether the DH, IH, and VH are necessary for each task. Sensitivity of behavioral tasks was confirmed using lidocaine (2 %, 1 μl) reversible inactivation. Subsequently, we examined the effects of silencing astrocytes, using fluorocitrate (FC, 1 mM/1 μl), into the DH, IH, and VH on these tasks. The effects of drugs were examined separately. We observed that injection of FC into the DH resulted in a significant impairment in MWM performance. In contrast, while FC injections into the IH or VH did not prevent platform localization during the acquisition phase, rats showed difficulty recalling the target zone during the retrieval phase. In the PA test, FC injection into the VH impaired task learning and memory. During the acquisition phase, FC injection into the DH or IH did not differ from the control in the number of shocks; however, during retrieval, there was a significant decrease in the latency before entering the dark chamber. The TPP test performance was impaired by FC injection in the IH. In sum, we show that glial cells, especially astrocytes in specific functional regions of the hippocampus, play distinct roles in processing aversive and rewarding experiences and contribute to the functional organization of the hippocampal longitudinal axis. [ABSTRACT FROM AUTHOR]

Background: Thiol-disulfide homeostasis (TDH) plays a pivotal role in various physiological mechanisms, including antioxidant defence, detoxification, apoptosis, regulation of enzyme activities and cellular signal transduction. TDH can be used as a biomarker to detect oxidative stress (OS) levels and ischemia status in the tissues. Coronary artery bypass grafting (CABG) surgery is a procedure associated with high oxidative stress. Dexmedetomidine, an alpha-2 agonist anaesthetic agent, has antioxidant effects. In this study, the effects of dexmedetomidine on oxidative stress in CABG surgery were investigated. Methods: Patients who underwent on-pump CABG surgery were divided into two groups: those receiving dexmedetomidine (Group D) and those not receiving dexmedetomidine (Group C). From anesthesia induction to the end of surgery, patients in Group D received intravenous infusions of 0.05–0.2 mcg/kg/min remifentanil and 0.2–0.7 mcg/kg/h dexmedetomidine. Patients in Group C received intravenous infusion of 0.05–0.2 mcg/kg/min remifentanil. Blood samples were collected from the patients 30 min before induction of anesthesia (T1), 30 min after removal of the aortic cross-clamp (T2), and at the end of the surgery (T3). Thiol-disulfide homeostasis (TDH) was assessed using a novel method. A novel automated method enables the determination of native thiols, total thiols and disulfides levels in plasma, allowing the calculation of their respective ratios. Results: In patients receiving dexmedetomidine, lower postoperative levels of disulfide, disulfide/native thiol, and disulfide/total thiol, along with higher native thiol/total thiol, were observed compared to the control group. (p < 0.05) Postoperative native thiol and total thiol levels were similar for both groups. (p > 0.05) Conclusions: In our study, through dynamic thiol-disulfide measurements, we found that levels of oxidative stress (OS) were lower in patients who received dexmedetomidine. We believe that the positive effects of dexmedetomidine on OS could be beneficial in CABG surgery. Furthermore, we anticipate that with further studies conducted in larger patient cohorts, the clinical utilization of dexmedetomidine will become more widespread. Trial registration number: NCT05895331 / 06.07.2023. [ABSTRACT FROM AUTHOR]

This work aims to target phosphoglycerate dehydrogenase (PHGDH), a promising druggable target, that is overexpressed in various types of cancer. A structure‐based approach was employed to identify novel inhibitors against the enzyme. A common five‐feature pharmacophore model (RRHDA) was constructed using the active site co‐crystalized ligands. These chemical features were responsible for showing inhibition. The generated models were subsequently subjected to the validation method using a test set, receiver‐operator characteristic analysis, enrichment factor, and Güner–Henry studies. The validated models were subjected to the screening of a dataset of natural compounds. The screened unique natural compounds (1795) were further selected for the interaction analysis and study of ligand binding affinity considering the effect of the hydrogen bonding and desolvation and hydrophobic interactions contribution to the binding. The natural compounds which exhibited good ligand binding efficiency were selected and further subjected to pharmacokinetics and pharmacodynamic study. The natural compounds which exhibited good ligand binding efficiency were selected and further subjected to pharmacokinetics and pharmacodynamic study. The finalized complexes were selected for the simulation studies and MM/PBSA‐based binding free energy calculations. This study expands the possibilities for the development of shortlisted molecules as novel anti‐cancer compounds. [ABSTRACT FROM AUTHOR]

Thrombin was immobilized on magnetic core‐shell mesoporous silica nanoparticles (Fe3O4@nSiO2@mSiO2) for the first time and used to screen enzyme inhibitors from extracts of Notopterygium incisum. The immobilized thrombin was characterized by Fourier‐transform infrared spectroscopy, transmission electronic microscopy, thermal gravimetric analysis, and vibrating sample magnetometry. The results demonstrated that the immobilized thrombin possessed good thermal stability and high‐temperature resistance for feasible storage and reuse. Two ligands, notopterol (1) and isoimperatorin (2) were fished out from the extract of N. incisum using the immobilized thrombin. They inhibited thrombin with IC50 values of 59.35 ± 1.420 and 107.8 ± 1.660 µM, respectively. This is the first report of thrombin‐inhibitory activity associated with notopterol and isoimperatorin. Meanwhile, the inhibition mechanism of both compounds was investigated by enzyme kinetic analysis and molecular docking. The method used enables rapid screening for thrombin inhibitors from medicinal plants, providing an efficient tool for the discovery of anti‐thrombotic active compounds. [ABSTRACT FROM AUTHOR]

Simple Summary: Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths, particularly among patients with a specific mutation in the KRAS gene known as KRAS G12C. Two targeted therapies, adagrasib and sotorasib, have been developed for this mutation. This manuscript reviews three key clinical trials that evaluated the efficacy of these drugs in patients with KRAS G12C-mutated NSCLC. We compare their effectiveness in slowing disease progression and examine their differing side effect profiles, both of which are crucial for treatment decisions. While both drugs demonstrate efficacy, their side effects can influence patient tolerance and overall experience. Understanding these differences enables physicians to make more informed choices about the most appropriate treatment for each patient. Our analysis indicates that, although the overall survival rates for both drugs are comparable, certain patients may derive greater benefits from one therapy over the other, depending on individual characteristics and the management of side effects. Background: The KRAS G12C mutation, prevalent in various malignancies, including non-small cell lung cancer (NSCLC), represents a unique therapeutic target. Adagrasib and sotorasib, two FDA-approved agents specifically targeting this mutation, have shown promise in clinical trials. This study aims to compare their efficacy in treating KRAS G12C-mutated NSCLC, drawing insights from pivotal clinical trials. Methods: We analyzed data from three key clinical trials: KRYSTAL-1, CodeBreak100, and CodeBreak200. Our methodology involved reconstructing individual patient data from published Kaplan–Meier curves using the IPDfromKM tool (Version 0.1.10). The primary endpoints were progression-free survival (PFS) and overall survival (OS), evaluated through hazard ratios (HRs) and the restricted mean survival time (RMST) method. Results: The HR for PFS favored adagrasib (HR: 0.90 [95% CI: 0.69, 1.19], p = 0.473), suggesting a non-significant trend toward better disease control compared to sotorasib. For OS, the HR was 0.99 [95% CI: 0.75, 1.33] (p = 0.969), indicating no significant difference between the two drugs. RMST analysis supported these findings, with adagrasib showing a consistently higher RMST in PFS at 6, 12, and 18 months. However, OS benefits converged over time, with adagrasib marginally surpassing sotorasib by the 18-month mark. Conclusions: This comprehensive analysis reveals that while adagrasib may offer a slight advantage in PFS, both drugs demonstrate comparable efficacy in OS for KRAS G12C-mutated NSCLC. The subtle differences observed, particularly in PFS, could inform clinical decision-making, emphasizing the need for personalized treatment strategies. Future research should focus on long-term effects and identifying patient subgroups that may benefit more from one drug over the other. [ABSTRACT FROM AUTHOR]

Simple Summary: The Yes-associated protein (YAP) is part of a system that regulates cell proliferation in response to changes in cell–cell and cell–matrix interactions. In malignant tumors, that system is almost always disrupted in ways that promote the stability of YAP. Mutations in genes encoding Ras proteins are found in 30% of all human cancers, but the mechanisms by which these mutated proteins promote cancer are still incompletely understood. Here, we investigated the regulation of YAP stability by the Ras oncogenes and found that while Ras does not directly regulate YAP, the stability of YAP is directly controlled by one of Ras's own effectors, the Rac1 GTPase, a small regulatory protein involved in controlling cell shape and migration. This regulation of YAP by Rac1 could potentially play an important role in the development of therapeutic resistance to Ras inhibitors, which we know can be promoted by the overexpression of YAP. Background: Oncogenic mutations in the KRAS gene are detected in >90% of pancreatic cancers (PC). In genetically engineered mouse models of PC, oncogenic KRAS drives the formation of precursor lesions and their progression to invasive PC. The Yes-associated Protein (YAP) is a transcriptional coactivator required for transformation by the RAS oncogenes and the development of PC. In Ras-driven tumors, YAP can also substitute for oncogenic KRAS to drive tumor survival after the repression of the oncogene. Ras oncoproteins exert their transforming properties through their downstream effectors, including the PI3K kinase, Rac1 GTPase, and MAPK pathways. Methods: To identify Ras effectors that regulate YAP, YAP levels were measured in PC cells exposed to inhibitors of oncogenic K-Ras and its effectors. Results: In PC cells, the inhibition of Rac1 leads to a time-dependent decline in YAP protein, which could be blocked by proteosome inhibitor MG132. This YAP degradation after Rac1 inhibition was observed in a range of cell lines using different Rac1 inhibitors, Rac1 siRNA, or expression of dominant negative Rac1T17N mutant. Several E3 ubiquitin ligases, including SCFβTrCP, regulate YAP protein stability. To be recognized by this ligase, the βTrCP degron of YAP (amino acid 383–388) requires its phosphorylation by casein kinase 1 at Ser384 and Ser387, but these events must first be primed by the phosphorylation of Ser381 by LATS1/2. Using Flag-tagged mutants of YAP, we show that YAP degradation after Rac1 inhibition requires the integrity of this degron and is blocked by the silencing of βTrCP1/2 and by the inhibition of casein kinase 1. Unexpectedly, YAP degradation after Rac1 inhibition was still observed after the silencing of LATS1/2 or in cells carrying a LATS1/2 double knockout. Conclusions: These results reveal Rac1 as an oncogenic KRAS effector that contributes to YAP stabilization in PC cells. They also show that this regulation of YAP by Rac1 requires the SCFβTrCP ligase but occurs independently of the LATS1/2 kinases. [ABSTRACT FROM AUTHOR]

Simple Summary: Nutritional assessment indicators have been recognized as useful in predicting treatment-related adverse events. In maintenance therapy with PARP inhibitors in ovarian cancer, treatment discontinuation due to treatment-related adverse events has been reported, but factors predicting these events are not identified. Our study suggested that PNI and mGPS can predict the risk of treatment discontinuation due to PARP inhibitor-related adverse events before starting maintenance therapy. This insight opens avenues for more personalized treatment plans, potentially improving patient outcomes. Background: Nutritional status is an important factor influencing toxicity of treatment. Nutritional assessment indicators such as the Prognostic Nutritional Index (PNI), Controlling Nutritional Status (CONUT) score and modified Glasgow Prognostic Score (mGPS) have been reported to be associated with treatment-related adverse events (AEs) for various malignancies. However, there are no reports investigating the relationship between nutritional status and AEs from poly-(ADP-ribose) polymerase (PARP) inhibitors (PARPi), which are widely used in recent years as maintenance therapy for ovarian cancer. Objective: The primary objective was to investigate the usefulness of nutritional assessment indicators in predicting treatment discontinuation due to AEs from PARPi. Methods: This multicenter retrospective study included patients diagnosed with ovarian cancer who received maintenance therapy with PARPi from January 2018 to December 2023. PNI, CONUT score, and mGPS were calculated based on hematological parameters measured within 7 days before the start of PARPi therapy. Results: A total of 272 patients received maintenance therapy with PARPi during the period, but due to the absence of the blood collection of albumin levels within one week or other exclusion criteria, 71 patients were finally included in this analysis. AEs were seen in 59 patients (83.1%), including 25 (35.2%) severe events (grade ≥3 in Common Terminology Criteria for Adverse Events v5.0). Eighteen patients (25.4%) discontinued treatment due to PARPi-related AEs. Low PNI (<48.44) and high mGPS (≥1) were predictors of treatment discontinuation in both univariate and multivariate analyses. CONUT was not a significant predictor in this study. Conclusions: Our study suggested that PNI and mGPS can predict the risk of treatment discontinuation due to PARPi-related AEs before starting maintenance therapy. This insight opens avenues for more personalized treatment plans, potentially improving patient outcomes. [ABSTRACT FROM AUTHOR]

Simple Summary: The standard of care for most women with advanced ovarian cancer is primary cytoreduction followed by platinum-based chemotherapy and paclitaxel. However, the use of neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) and adjuvant chemotherapy is not inferior, according to prospective randomized trials. Ovarian cancer has a low mutational load but exhibits a high detection rate of molecular alterations in various genes. It remains unclear whether this is an intrinsic feature of ovarian cancer or if it is due to the administration of a platinum combination during NACT. Our study aimed to determine whether NACT affects the tumor's molecular profile. Any modifications in these areas would need to be identified in the initial therapeutic planning, especially in the era of poly (ADP-ribose) polymerase (PARP) inhibitors. Background: Neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) and adjuvant chemotherapy is a therapeutic choice for women with advanced ovarian cancer. Whether NACT affects the tumor's molecular profile has not been determined. Methods: This was a retrospective study of patients with advanced-stage epithelial ovarian cancer treated with NACT at oncology departments affiliated with the Hellenic Cooperative Oncology Group (HeCOG). Tumor molecular profiling was performed on formalin-fixed and paraffin-embedded (FFPE) tumor pre- and post-NACT tissues. Homologous recombination deficiency (HRD), tumor-infiltrating lymphocytes (TILs), tumor molecular alterations, and tumor mutational burden (TMB) via next-generation sequencing analysis were assessed. Results: Overall, tumors from 36 patients were assessed, and molecular profiling was evaluated in 20 paired tumor samples. HRD positivity exhibited no significant change between pre- and post-NACT tumors. The BRCA1/2 mutational status remained constant, irrespective of the treatment administration. Pre-NACT tumors tended to exhibit a lower percentage of intratumoral TILs compared to post-NACT tumors (p = 0.004). Differences in the mutation profile between pre- and post-treatment tissue were observed in 33.33% (6/18) of the cases. The mean tumor cell content (TCC) (p-value: 0.0840) and the mean genomic instability score (p-value: 0.0636) decreased slightly numerically after therapy. A moderate inverse relationship was observed between the pre-NACT TMB and the chemotherapy response score (p-value: 0.038), indicating this correlation is statistically significant. Conclusion: This study provides insights into the effect of NACT on the tumor molecular landscape. While BRCA1/2 and HRD status remained stable, an increase in TIL proportion and changes in the mutational profiles were observed post-treatment. [ABSTRACT FROM AUTHOR]

Proteases catalyze hydrolysis of amide bonds within peptides and proteins, therefore they play crucial functions for organism functioning, but also in industry to facilitate numerous processes. Feather-degrading fungus Onygena corvina (O. corvina) is loaded with numerous proteases that can be utilized for variety of applications. The most active species of these enzymes is heat-sensitive serine protease (NHSSP), from O. corvina fungi and due to its potential applications in industry is an alternative to proteinase K. The uniqueness of NHSSP relies on the ability of this enzyme to hydrolyze peptides at neutral to acidic pH values between 5.0 and 8.5, with an optimum of 6.8 and a temperature activity ranging from 15 to 50 °C making NHSSP exceptionally universal enzyme. Thus, we have performed the in-depth characterization of NHSSP substrate specificity by using a positional scanning substrate combinatorial library (PS-SCL). Afterward, we obtained a set of fluorescent substrates hydrolyzed by NHSSP that served as a leading sequence for the first tailored covalent inhibitor of this enzyme, containing a diphenylphosphonate as a warhead and MeOSuc amine protecting group. Our first inhibitor for NHSSP binds potently with target protease and is a tool for future study of this enzyme functions. [Display omitted] • Catalytic preferences of NHSSP at the S1–S4 pockets were determined. • NHSSP recognizes many amino acids at the P1 position, including hydrophobic, bulky, and aliphatic residues. • NHSSP possesses broad substrate specificity at the P2 and P3 positions, while the S4 pocket is the most restricted. • Potent substrate for NHSSP was designed, synthesized, and validated. • First inhibitor for NHSSP protease was designed and synthesized and inhibits NHSSP with k obs /I = 5.3 × 106 M−1s−1. [ABSTRACT FROM AUTHOR]

Background: Huashi Baidu Formula (HBF) is a clinical formula known for its efficacy against coronavirus disease 2019 (COVID-19). HBF may reduce the number of patients with abnormal serum creatinine while improving respiratory symptoms, suggesting that this formula may have potential for treating acute kidney injury (AKI). However, the protective effect of HBF on AKI has not been definitively confirmed, and the mechanism remains unclear. Therefore, the present study explored the renoprotective effects and molecular mechanisms of HBF and screened for its active ingredients to identify new potential applications of renoprotection by HBF. Methods: The present study first assessed the protective effects of HBF on AKI in a DOX-induced mouse model. Then, RNA-seq and bioinformatics analyses were used to explore the related pathological processes and potential molecular mechanisms, which were subsequently validated using qRT-PCR and Western blotting. Furthermore, candidate compounds with potential binding affinity to two pivotal targets, sphingosine kinase 1 (SphK1) and plasminogen activator inhibitor-1 (PAI-1), were screened from the 29 constituents present in the blood using Microscale Thermophoresis (MST). Finally, to identify the active ingredients, the candidate components were re-screened using the SphK1 kinase activity detection system or the uPA/PAI-1 substrate colorimetric assay system. Results: In the DOX-induced AKI mouse model, therapeutic administration of HBF significantly reduced the levels of CRE, BUN, TNF-α, IL-1β, IL-6, and UA in plasma and the levels of MDA, T-CHO, and TG in kidney tissue. Additionally, the levels of TP and Alb in plasma and SOD and CAT in the kidney tissue were significantly increased. Histopathological assessment revealed that HBF reduced tubular vacuolation, renal interstitial inflammatory cell infiltration, tubular atrophy, and positive staining of renal interstitial collagen. RNA-seq and bioinformatics analyses showed that oxidative stress, the immune-inflammatory response, and extracellular matrix (ECM) formation could be the pathological processes that HBF targets to exerts its renoprotective effects. Furthermore, HBF regulated the APJ/SPHK1/NF-κB and APJ/PAI-1/TGFβ signaling axes and reduced the phosphorylation levels of NF-κB p65 and SMAD2 and the expression of cytokines and the ECM downstream of the axis. Finally, six SphK1 inhibitors (paeoniflorin, astragalin, emodin, glycyrrhisoflavone, quercetin, and liquiritigenin) and three PAI-1 inhibitors (glycyrrhisoflavone, licochalcone B, and isoliquiritigenin) were identified as potentially active ingredients in HBF. Conclusion: In brief, our investigation underscores the renoprotective effect of HBF in a DOX-induced AKI model mice, elucidating its mechanisms through distinct pathological processes and identifying key bioactive compounds. These findings offer new insights for broadening the clinical applications of HBF and unravelling its molecular mode of action. [ABSTRACT FROM AUTHOR]

In classic galactosemia (CG) patients, aldose reductase (AR) converts galactose to galactitol. In a phase 1/2, placebo‐controlled study (NCT04117711), safety, pharmacokinetics (PK), and pharmacodynamics (PD) of govorestat were evaluated after single and multiple ascending doses (0.5‐40 mg/kg) in healthy adults (n = 81) and CG patients (n = 14). Levels of govorestat in plasma and cerebrospinal fluid (CSF) and blood levels of galactitol, galactose, and galactose‐1‐phosphate (Gal‐1p) were measured for population PK and PK/PD analyses. Govorestat was well tolerated. Adverse event frequency was comparable between placebo and govorestat. Govorestat PK displayed a 2‐compartment model with sequential zero‐ and first‐order absorption, and no effect of demographic factors. Multiple‐dose PK of govorestat was linear in the 0.5‐40 mg/kg range, and CSF levels increased dose dependently. Elimination half‐life was ∼10 h. PK/PD modeling supported once‐daily dosing. Change from baseline in galactitol was −15% ± 9% with placebo and −19% ± 10%, −46% ± 4%, and −51% ± 5% with govorestat 5, 20, and 40 mg/kg, respectively, thus was similar for 20 and 40 mg/kg. Govorestat did not affect galactose or Gal‐1p levels. In conclusion, govorestat displayed a favorable safety, PK, and PD profile in humans, and reduced galactitol levels in the same magnitude (∼50%) as in a rat model of CG that demonstrated an efficacy benefit on neurological, behavioral, and ocular outcomes. [ABSTRACT FROM AUTHOR]

Astragalus membranaceus is a traditional Chinese medicine with multiple pharmacological activities. Modern pharmacological research has found that Astragalus membranaceus extract has an inhibitory effect on α-glucosidase, however, which component can inhibit the activity of α-glucosidase and its degree of inhibition are unknown. To address this issue, this study used affinity ultrafiltration screening combined with UPLC-ESI-Orbitrap-MS technology to screen α-glucosidase inhibitors in Astragalus membranaceus. Using affinity ultrafiltration technology, we obtained the active components, and using UPLC-ESI-Orbitrap-MS technology, we quickly analyzed and identified them. As a result, a total of 8 ingredients were selected as α-glucosidase inhibitors. [ABSTRACT FROM AUTHOR]

Aims: While randomized controlled trials data on the long‐term effect of glucose‐lowering drugs (GLDs) on liver‐related outcomes are lacking, population‐based studies have evaluated the associations of GLDs with liver‐related outcomes in individuals with type 2 diabetes (T2D). we aimed to conduct a systematic review of population‐based studies evaluating the effects of GLDs on liver‐related outcomes in people with T2D. Methods: PubMed, Web of Science, and Embase databases were systematically searched for population‐based studies testing the associations of GLDs with liver‐related outcomes in individuals with T2D and no liver disease other than non‐alcoholic fatty liver disease (NAFLD) from inception to 23 February 2024. GLDs included SGLT2is, TZDs, insulin, GLP‐1 RAs and dipeptidyl peptidase‐4 inhibitors (DPP4Is). Results: Ten cohort studies, comprising 1,274,641 participants, met the inclusion criteria. The median follow‐up period ranged from 8.9 to 76 months. Of all the GLDs under investigation, SGLT2is were associated with the strongest reduction in NAFLD incidence, cirrhosis, and composite liver‐related events compared to other medications. TZDs were associated with a reduced risk of developing NAFLD and cirrhosis but were not significantly associated with a lower incidence of hepatocellular carcinoma. GLP‐1 RAs demonstrated a significant association with reduced liver‐related mortality. Conclusions: Observational data from population‐based studies suggest that GLDs such as SGLT2is are associated with beneficial long‐term liver‐related outcomes in T2D patients with NAFLD. Additional studies, including randomized controlled trials with long‐term follow‐up, are needed to confirm these findings. Registration Number: PROSPERO CRD442024536872. [ABSTRACT FROM AUTHOR]

A 14-year-old patient presents with hematuria and proteinuria. Clinical evaluation reveals a positive anti-nuclear antibody titer, positive anti-double stranded DNA antibody and hypocomplementemia. Systemic lupus erythematosus (SLE) is diagnosed based on the 2019 EULAR/ACR (European League Against Rheumatism/American College of Rheumatology) classification criteria (Aringer et al. Arthritis Rheumatol 71:1400–1412, 2019). A kidney biopsy is performed that confirms the presence of immune complex glomerulonephritis, ISN-RPS (International Society of Nephrology/Renal Pathology Society) class IV (Bajema et al. Kidney Int 93:789–796, 2018). According to the latest clinical practice guidelines (Rovin et al. Kidney Int 100:753–779, 2021; Fanouriakis et al. Ann Rheum Dis 83:15–29, 2023), there are alternatives to treating this patient with cyclophosphamide. But what if this patient also presented with oliguria and volume overload requiring intensive care and dialysis? What if this patient also presented with altered mental status and seizures, and was diagnosed with neuropsychiatric lupus? What if this patient was also diagnosed with a pulmonary hemorrhage and respiratory failure? The clinical practice guidelines do not address these scenarios that are not uncommon in patients with SLE. Moreover, in some countries worldwide, patients do not have the privilege of access to biologics or more expensive alternatives. The purpose of this review is to evaluate the contemporary options for initial treatment of nephritis in patients with SLE. [ABSTRACT FROM AUTHOR]

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The ubiquitin‐conjugating E2 enzymes play a central role in ubiquitin transfer. Disruptions to the ubiquitin system are implicated in multiple diseases, and as a result, molecules that modulate the activity of the ubiquitin system are of interest. E2 enzyme function relies on interactions with partner proteins, and the disruption of these is an effective way to modulate activity. Here, we report the discovery of ubiquitin variants (UbVs) that inhibit the E2 enzyme, Ube2d2 (UbcH5b). The six UbVs identified inhibit ubiquitin chain building, and the structural and biophysical characterisation of two of these demonstrate they bind to Ube2d2 with low micromolar affinity and high specificity. Both characterised UbVs bind at a site that overlaps with E1 binding, while the more inhibitory UbV has an additional binding site that blocks a critical non‐covalent ubiquitin‐binding site on the E2 enzyme. The discovery of novel protein‐based ubiquitin derivatives that inhibit protein–protein interactions is an important step towards discovering small molecules that inhibit the activity of E2 enzymes. Furthermore, the specificity of the UbVs within the Ube2d family suggests that it may be possible to develop tools to selectively inhibit highly related E2 enzymes. [ABSTRACT FROM AUTHOR]

Enzymes are biologically active complex protein molecules that catalyze most chemical reactions in living organisms, and their inhibitors accelerate biological processes. This review emphasizes medicinal food plants and their isolated chemicals inhibiting clinically important enzymes in common diseases. A mechanistic overview was investigated to explain the mechanism of these food bases enzyme inhibitors. The enzyme inhibition potential of medicinal food plants and their isolated substances was searched in Ovid, PubMed, Science Direct, Scopus, and Google Scholar. Cholinesterase, amylase, glucosidase, xanthine oxidase, tyrosinase, urease, lipoxygenase, and others were inhibited by crude extracts, solvent fractions, or isolated pure chemicals from medicinal food plants. Several natural compounds have shown tyrosinase inhibition potential, including quercetin, glabridin, phloretin-4-O-β-D-glucopyranoside, lupinalbin, and others. Some of these compounds' inhibitory kinetics and molecular mechanisms are also discussed. Phenolics and flavonoids inhibit enzyme activity best among the secondary metabolites investigated. Several studies showed flavonoids' significant antioxidant and anti-inflammatory activities, highlighting their medicinal potential. Overall, many medicinal food plants, their crude extracts/fractions, and isolated compounds have been studied, and some promising compounds depending on the enzyme have been found. Still, more studies are recommended to derive potential pharmacologically active functional foods. [ABSTRACT FROM AUTHOR]

The human Golgi α-mannosidase, hGMII, removes two mannose residues from GlcNAc-Man5GlcNAc2 to produce GlcNAcMan3GlcNAc2, the precursor of all complex N-glycans including tumour-associated ones. The natural product GMII inhibitor, swainsonine, blocks processing of cancer-associated N-glycans, but also inhibits the four other human α-mannosidases, rendering it unsuitable for clinical use. Our previous structure-guided screening of iminosugar pyrrolidine and piperidine fragments identified two micromolar hGMII inhibitors occupying the enzyme active pockets in adjacent, partially overlapping sites. Here we demonstrate that fusing these fragments yields swainsonine-configured indolizidines featuring a C3-substituent that act as selective hGMII inhibitors. Our structure-guided GMII-selective inhibitor design complements a recent combinatorial approach that yielded similarly configured and substituted indolizidine GMII inhibitors, and holds promise for the potential future development of anti-cancer agents targeting Golgi N-glycan processing. [ABSTRACT FROM AUTHOR]

Proteins are the primary targets of almost all small molecule drugs. However, even the most selectively designed drugs can potentially target several unknown proteins. Identification of potential drug targets can facilitate design of new drugs and repurposing of existing ones. Current state-of-the-art proteomics methodologies enable screening of thousands of proteins against a limited number of drug molecules. Here we report the development of a label-free quantitative proteomics approach that enables proteome-wide screening of small organic molecules in a scalable, reproducible, and rapid manner by streamlining the proteome integral solubility alteration (PISA) assay. We used rat organs ex-vivo to determine organ specific targets of medical drugs and enzyme inhibitors to identify drug targets for common drugs such as Ibuprofen. Finally, global drug profiling revealed overarching trends of how small molecules affect the proteome through either direct or indirect protein interactions. Many drug targets remain unknown for small molecules. Here, the authors develop a label-free Proteome Integral Solubility Alteration (PISA) workflow to automate target identification and analysis. Applied to rat organs, the authors identify previously unknown drug targets for common medication. [ABSTRACT FROM AUTHOR]

Simple Summary: Inhibition of the DNA repair protein PARP-1 is a promising concept in cancer therapy. More recently, PARP-1 has been revealed as a possible target in colorectal cancer, which is the second leading cause of cancer-related death worldwide. In this work, we screened a compound library to identify novel PARP inhibitors with low cytotoxicity and tested their efficacy in colorectal cancer cell models with and without defects in the DNA damage response. Furthermore, we evaluated whether the putative PARP inhibitors synergize with chemotherapeutic drugs used in the clinics to treat colorectal cancer patients. Using various experimental approaches, we were able to identify two promising molecules with potent PARP inhibition in colorectal cancer cells without causing cytotoxicity on their own. Moreover, the novel PARP inhibitors sensitized colorectal cancer cells to the anticancer drug irinotecan dependent on homologous recombination deficiency. Remarkably, the clinically approved PARP inhibitor olaparib displayed the strongest synergistic effects, but it was also cytotoxic as a single agent in wildtype colorectal cancer cells. The novel PARP inhibitors might, therefore, be useful for a combination therapy with irinotecan to avoid overlapping toxicity on healthy tissue such as bone marrow, which warrants further preclinical studies. The DNA repair protein PARP-1 emerged as a valuable target in the treatment of tumor entities with deficiencies of BRCA1/2, such as breast cancer. More recently, the application of PARP inhibitors (PARPi) such as olaparib has been expanded to other cancer entities including colorectal cancer (CRC). We previously demonstrated that PARP-1 is overexpressed in human CRC and promotes CRC progression in a mouse model. However, acquired resistance to PARPi and cytotoxicity-mediated adverse effects limit their clinical applicability. Here, we detailed the role of PARP-1 as a therapeutic target in CRC and studied the efficacy of novel PARPi compounds in wildtype (WT) and DNA repair-deficient CRC cell lines together with the chemotherapeutics irinotecan (IT), 5-fluorouracil (5-FU), and oxaliplatin (OXA). Based on the ComPlat molecule archive, we identified novel PARPi candidates by molecular docking experiments in silico, which were then confirmed by in vitro PARP activity measurements. Two promising candidates (X17613 and X17618) also showed potent PARP-1 inhibition in a CRC cell-based assay. In contrast to olaparib, the PARPi candidates caused no PARP-1 trapping and, consistently, were not or only weakly cytotoxic in WT CRC cells and their BRCA2- or ATR-deficient counterparts. Importantly, both PARPi candidates did not affect the viability of nonmalignant human colonic epithelial cells. While both olaparib and veliparib increased the sensitivity of WT CRC cells towards IT, no synergism was observed for X17613 and X17618. Finally, we provided evidence that all PARPi (olaparib > veliparib > X17613 > X17618) synergize with chemotherapeutic drugs (IT > OXA) in a BRCA2-dependent manner in CRC cells, whereas ATR deficiency had only a minor impact. Collectively, our study identified novel lead structures with potent PARP-1 inhibitory activity in CRC cells but low cytotoxicity due to the lack of PARP-1 trapping, which synergized with IT in homologous recombination deficiency. [ABSTRACT FROM AUTHOR]

Vorasidenib (VORANIGO®; Servier) is an orally administered, first-in-class, highly brain-penetrant dual inhibitor of mutant isocitrate dehydrogenase 1 and 2 (IDH1/2) enzymes being developed for use in IDH-mutant diffuse glioma. Vorasidenib received its first approval on 6 August 2024, in the USA, for the treatment of adult and pediatric patients aged 12 years and older with grade 2 astrocytoma or oligodendroglioma with a susceptible IDH1 or IDH2 mutation following surgery, including biopsy, sub-total resection, or gross total resection. Approval was based on results from the multinational phase III INDIGO trial, in which vorasidenib significantly improved progression-free survival and time to the next anticancer intervention relative to placebo. In the EU and other countries worldwide, regulatory review of vorasidenib in IDH-mutant glioma is currently underway. This article summarizes the milestones in the development of vorasidenib leading to this first approval for glioma. [ABSTRACT FROM AUTHOR]

Taniborbactam (formerly known as VNRX-5133) is a novel bicyclic boronate β-lactamase inhibitor of serine β-lactamases (SBLs) [Ambler classes A, C, and D] and metallo-β-lactamases (MBLs) [Ambler class B], including NDM and VIM, but not IMP. Cefepime–taniborbactam is active in vitro against most isolates of carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPA), including both carbapenemase-producing and carbapenemase-non-producing CRE and CRPA, as well as against multidrug-resistant (MDR), ceftazidime-avibactam-resistant, meropenem-vaborbactam-resistant, and ceftolozane-tazobactam-resistant Enterobacterales and P. aeruginosa. The addition of taniborbactam to cefepime resulted in a > 64-fold reduction in MIC90 compared with cefepime alone for a 2018–2021 global collection of > 13,000 clinical isolates of Enterobacterales. In the same study, against > 4600 P. aeruginosa, a fourfold MIC reduction was observed with cefepime–taniborbactam, compared with cefepime alone. Whole genome sequencing studies have shown that resistance towards cefepime–taniborbactam in Enterobacterales arises due to the presence of multiple resistance mechanisms, often in concert, including production of IMP, PBP3 alterations, permeability (porin) defects, and upregulation of efflux pumps. In P. aeruginosa, elevated cefepime–taniborbactam MICs are also associated with the presence of multiple, concurrent mechanisms, most frequently IMP, PBP3 mutations, and upregulation of efflux pumps, as well as AmpC (PDC) overexpression. The pharmacokinetics of taniborbactam are dose proportional, follow a linear model, and do not appear to be affected when combined with cefepime. Taniborbactam's approximate volume of distribution (Vd) at steady state is 20 L and the approximate elimination half-life (t½) is 2.3 h, which are similar to cefepime. Furthermore, like cefepime, taniborbactam is primarily cleared renally, and clearance corresponds with renal function. Pharmacodynamic studies (in vitro and in vivo) have reported that cefepime–taniborbactam has bactericidal activity against various β-lactamase-producing Gram-negative bacilli that are not susceptible to cefepime alone. It has been reported that antimicrobial activity best correlated with taniborbactam exposure (area under the curve). A phase III clinical trial showed that cefepime–taniborbactam (2 g/0.5 g administered as an intravenous infusion over 2 h) was superior to meropenem for the treatment of complicated urinary tract infection (cUTI), including acute pyelonephritis, caused by Enterobacterales species and P. aeruginosa while demonstrating similar safety compared with meropenem. The safety and tolerability of taniborbactam and cefepime–taniborbactam has been reported in one pharmacokinetic trial, and in two pharmacokinetic trials and one phase III clinical trial, respectively. Cefepime–taniborbactam appears to be well tolerated in both healthy subjects and patients. Headache and gastrointestinal upset are the most common drug-related adverse effects associated with cefepime–taniborbactam use. Cefepime–taniborbactam will likely have a role in the treatment of infections proven or suspected to be caused by MDR Gram-negative bacteria, including Enterobacterales and P. aeruginosa. In particular, it may be useful in the treatment of infections caused by isolates that harbor an MBL (NDM, VIM) enzyme, although further clinical data are needed. Additional safety and efficacy studies may support indications for cefepime–taniborbactam beyond cUTI. [ABSTRACT FROM AUTHOR]

Deubiquitinating enzymes (DUBs) prevent ubiquitination by eliminating ubiquitin from their substrates. Deubiquitinating enzymes have important roles in a number of cell biology subfields that are highly relevant to diseases like neurodegeneration, cancer, autoimmune disorders, and long-term inflammation. Deubiquitinating enzymes feature a well-defined active site and, for the most part, catalytic cysteine, which makes them appealing targets for small-molecule drug development. Ubiquitin-specific protease 46 (USP46) is a member of the ubiquitin-specific protease family, the largest subfamily of DUBs. Over the past 10 years, some studies have steadily demonstrated the significance of USP46 in several biological processes, although it was identified later and early research progress was modest. Specifically, in the last few years, the carcinogenic properties of USP46 have become more apparent. In the current review, we provide a comprehensive overview of the current knowledge about USP46 including its characteristics, structure, inhibitors, function in diseases, especially in the nervous system, and the correlation of USP46 with cancers. [ABSTRACT FROM AUTHOR]

Diazo peptides have been described earlier, however, due to their high reactivity have not been broadly used until today. Here, we report the preparation, properties, and applications of chemically stable internal diazo peptides. Peptidyl phosphoranylidene‐esters and amides were found to react with triflyl azide primarily to novel 3,4‐disubstituted triazolyl‐peptides. Nonaflyl azide instead furnished diazo peptides, which are chemically stable from pH 1–14 as amides and from pH 1–8 as esters. Thus, diazo peptides prepared by solid phase peptide synthesis were stable to final deprotection with 95 % trifluoroacetic acid. Diazo peptides with the recognition sequence of caspase‐3 were identified as specific, covalent, and irreversible inhibitors of this enzyme at low nanomolar concentrations. A fluorescent diazo peptide entered living cells enabling microscopic imaging and quantification of apoptotic cells via flow cytometry. Thus, internal diazo peptides constitute a novel class of activity‐based probes and enzyme inhibitors useful in chemical biology and medicinal chemistry. [ABSTRACT FROM AUTHOR]

Background: Enhancing the prognosis and treatment outcomes of oral cancer relies heavily on its early detection. This study aims to establish a connection between serum and salivary dipeptidyl peptidase-4 (DPP-4) levels and oral squamous cell carcinoma (OSCC), comparing them with oral potentially malignant lesions (OPMLs) and control subjects and validating salivary DPP-4 as a diagnostic marker for the early detection of oral cancer. Methodology: Forty-five systemically healthy individuals were categorized into three groups: Group I consisted of 15 patients diagnosed with OSCC, Group II comprised 15 patients with OPMLs (including leukoplakia and oral lichen planus), and Group III included 15 participants without any oral mucosal lesions. Serum and whole unstimulated salivary samples were collected from all participants to assess DPP-4 levels using an enzyme-linked immunosorbent assay (ELISA) kit. Receiver operating characteristic (ROC) analysis was conducted to determine the area under the curve (AUC), sensitivity, specificity, and diagnostic accuracy of DPP-4. Results: Both serum and salivary DPP-4 levels were highest in the healthy group, followed by OPMLs, and lowest in the OSCC group, with statistically significant differences observed. ROC analysis demonstrated excellent diagnostic accuracy of salivary DPP-4 in distinguishing OSCC from healthy individuals, OPMLs from healthy individuals, and OSCC from OPMLs, with accuracies of 100%, 100%, and 96.67%, respectively. Salivary DPP-4 levels also exhibited a statistically significant correlation with OSCC grades. Conclusions: DPP-4 appears to play a protective, anti-oncogenic role in maintaining oral tissue health. The remarkable diagnostic accuracy of both serum and salivary DPP-4 in discriminating between OSCC, OPMLs, and healthy controls suggests its potential utility as a well-established marker for early oral cancer diagnosis. Salivary DPP-4, being non-invasive, could serve as a convenient chair-side diagnostic tool for the early detection of OSCC. Clinical trial registration: The study was retrospectively registered on clinicaltrial.gov with NCT06087042, date of registration (first posted date): 17/10/2023 [ABSTRACT FROM AUTHOR]

5-Lipoxygenase (5-LOX) is a key enzyme involved in the biosynthesis of pro-inflammatory leukotrienes, leading to asthma. Developing potent 5-LOX inhibitors are highly attractive. In this research the previously synthesized isoxazole derivatives has been investigated against 5-LOX inhibitory and antioxidant in vitro assay. The compound 3 caused concentration dependent inhibition of 5-LOX with overall IC50 value of 8.47 μM. The investigated compounds C5 also exhibited good 5-LOX inhibitory effect. The IC50 demonstrated for C5 was 10.48. Among the 10 synthesized compounds, the potential 5-LOX inhibitory effect was reported for C6. The most potent compound which showed excellent free radical scavenging effect was C3 having IC50 value of 10.96 μM. The next most potent antioxidant activity was reported for C5 which non-significantly showed free radical scavenging effect. The IC50 value observed for C5 was 13.12 μM. Compound C6 also showed potent dose dependent antioxidant effect with IC50 value of 18.87 μM having percent inhibition of 91.63±0.55, 88.45±0.49, 83.53±0.45, 78.42±0.66 and 73.72±0.64 at concentration 1000–62.5 μg/mL respectively. Among the tested compounds, C6 was found most potent which showed significant 5-LOX percent inhibition assay and also reported the minimum IC50 value comparable to the reference drug. The in vitro 5-LOX enzymes inhibition assays of C5 and C3 also showed excellent percent inhibition and good potency next to C6. We concluded that amongst the investigated designed molecules the C3 was found best potent and showed significant dose dependent antioxidant activity against DPPH screening. The IC50 value reported for C3 was found good as compared to standard drug. Moreover, C5 and C6 also showed excellent free radical scavenging effect against DPPH assay. Computational methods have also been employed to explore the probable interaction model of inhibitors and enzyme active sites, and also to correlate the results of in silico and in vitro studies. [ABSTRACT FROM AUTHOR]

Photoregulation of biomolecules has become crucial tools in chemical biology, because light enables access under mild conditions and with delicate spatiotemporal control. The control of enzyme activity in a reversible way is a challenge. To achieve it, a facile approach is to use photoswitchable inhibitors. This review highlights recent progress in photoswitchable inhibitors based on azobenzenes units. The progress suggests that the incorporation of an azobenzene unit to a known inhibitor is an effective method for preparing a photoswitchable inhibitor, and with these photoswitchable inhibitors, the activity of enzymes can be regulated by optical control, which is valuable in both basic science and therapeutic applications. [ABSTRACT FROM AUTHOR]

There is evidence that astrocytes modulate synaptic transmission in the nucleus tractus solitarius (NTS) interacting with glutamatergic and purinergic mechanisms. Here, using in situ working heart-brainstem preparations, we evaluated the involvement of astrocyte and glutamatergic/purinergic neurotransmission in the processing of autonomic and respiratory pathways in the NTS of control and rats exposed to sustained hypoxia (SH). Baseline autonomic and respiratory activities and the responses to chemoreflex activation (KCN) were evaluated before and after microinjections of fluorocitrate (FCt, an astrocyte metabolic inhibitor), kynurenic acid, and pyridoxalphosphate-6-azophenyl-2′,4′-disulfonate (PPADS) (nonselective antagonists of glutamatergic and purinergic receptors) into the rostral aspect of the caudal commissural NTS. FCt had no effects on the baseline parameters evaluated but reduced the bradycardic response to chemoreflex activation in SH rats. FCt combined with kynurenic acid and PPADS in control rats reduced the baseline duration of expiration, which was attenuated after SH. FCt produced a large increase in PN frequency discharge in control rats, which was reduced after SH, indicating a reduction in the astrocyte modulation after SH. The data show that 1) the bradycardic component of the peripheral chemoreflex is reduced in SH rats after astrocytes inhibition, 2) the inhibition of astrocytes in the presence of double antagonists in the NTS affects the modulation of baseline duration of expiration in control but not in SH rats, and 3) the autonomic and respiratory responses to chemoreflex activation are mediated by glutamatergic and purinergic receptors in the rostral aspect of the caudal commissural NTS. NEW & NOTEWORTHY: Our findings indicate that the neurotransmission of autonomic and respiratory components of the peripheral chemoreflex in the nucleus tractus solitarius (NTS) is mediated by glutamatergic and purinergic mechanisms and reveal a selective involvement of NTS astrocytes in controlling the chemoreflex parasympathetic response in rats exposed to sustained hypoxia (SH) and the baseline duration of expiration mainly in control rats, indicating a selective role for astrocytes modulation in the NTS of control and SH rats. [ABSTRACT FROM AUTHOR]

Simple Summary: Subependymal giant cell astrocytoma is a slow-growing brain tumor affecting children and young adults. Despite the characteristic molecular and clinical features, the severity of the disease varies from patient to patient, and, in addition, tumors in their early stages can be asymptomatic for a long time. Morbidity and mortality are due to the location of the tumor, which can obstruct the flow of cerebrospinal fluid, leading to progressive hydrocephalus and even death. The etiology and the response to treatment are still poorly understood due to the diversity of the background and the course of the disease. Therefore, this review aims to present and discuss the latest research on SEGA, its diagnosis, and treatment. Subependymal giant cell astrocytoma (SEGA) is most often found in patients with TSC (Tuberous Sclerosis Complex). Although it has been classified as a benign tumor, it may create a serious medical problem leading to grave consequences, including young patient demise. Surgery and chemotherapy belong to the gold standard of treatment. A broader pharmacological approach involves the ever-growing number of rapalogs and ATP-competitive inhibitors, as well as compounds targeting other kinases, such as dual PI3K/mTOR inhibitors and CK2 kinase inhibitors. Novel approaches may utilize noncoding RNA-based therapeutics and are extensively investigated to this end. The purpose of our review was to characterize SEGA and discuss the latest trends in the diagnosis and therapy of this disease. [ABSTRACT FROM AUTHOR]