Excretion Studies Research Articles

LC-MS/(MS) confirmatory doping control analysis of intact phase II metabolites of methenolone and mesterolone after Girard's Reagent T derivatization.

In the present study, the application and evaluation of Girard's Reagent T (GRT) derivatization for the simultaneous detection and significantly important identification of different phase II methenolone and mesterolone metabolites by LC-MS/(MS) are presented. For the LC-MS analysis of target analytes two complementary isolation methods were developed; a derivatization and shoot method in which native urine is diluted with derivatization reagent and is injected directly to LC-MS and a liquid-liquid extraction method, using ethyl acetate at pH 4.5, for the effective isolation of both sulfate and glucuronide metabolites of the named steroids as well as of their free counterparts. For the evaluation of the proposed protocols, urine samples from methenolone and mesterolone excretion studies were analyzed against at least one sample from a different excretion study. Retention times, along with product ion ratios, were evaluated according to the WADA TD2021IDCR requirements, in order to determine maximum detection and identification time windows for each metabolite. Established identification windows obtained after LC-MS/(MS) analysis were further compared with those obtained after GC-MS/(MS) analysis of the same samples from the same excretion studies, for the most common analytes monitored by GC-MS/(MS). Full validation was performed for the developed derivatization and shoot method for the identification of methenolone metabolite, 3α-hydroxy-1-methylen-5α-androstan-17-one-3-glucuronide (mth3). Overall, the GRT derivatization presented herein offers a tool for the simultaneous sensitive detection of free, intact glucuronide and sulfate metabolites by LC-MS/(MS) that enhance significantly the detection and identification time windows of specific methenolone and mesterolone metabolites for doping control analysis.

Tiered approach to evaluate the CYP3A victim and perpetrator drug-drug interaction potential for vonoprazan using PBPK modeling and clinical data to inform labeling.

Vonoprazan is metabolized extensively through CYP3A and is an in vitro time-dependent inhibitor of CYP3A. A tiered approach was applied to understand the CYP3A victim and perpetrator drug-drug interaction (DDI) potential for vonoprazan. Mechanistic static modeling suggested vonoprazan is a potential clinically relevant CYP3A inhibitor. Thus, a clinical study was conducted to evaluate the impact of vonoprazan on the exposure of oral midazolam, an index substrate for CYP3A. A physiologically-based pharmacokinetic (PBPK) model for vonoprazan was also developed using in vitro data, drug- and system-specific parameters, and clinical data and observations from a [14 C] human absorption, distribution, metabolism, and excretion study. The PBPK model was refined and verified using data from a clinical DDI study with the strong CYP3A inhibitor, clarithromycin, to confirm the fraction metabolized by CYP3A, and the oral midazolam clinical DDI data assessing vonoprazan as a time-dependent inhibitor of CYP3A. The verified PBPK model was applied to simulate the anticipated changes in vonoprazan exposure due to moderate and strong CYP3A inducers (efavirenz and rifampin, respectively). The clinical midazolam DDI study indicated weak inhibition of CYP3A, with a less than twofold increase in midazolam exposure. PBPK simulations projected a 50% to 80% reduction in vonoprazan exposure when administered concomitantly with moderate or strong CYP3A inducers. Based on these results, the vonoprazan label was revised and states that lower doses of sensitive CYP3A substrates with a narrow therapeutic index should be used when administered concomitantly with vonoprazan, and co-administration with moderate and strong CYP3A inducers should be avoided.

Estudo da excreção urinária de condroitim sulfato após administração intramuscular da associação de condroitim sulfato e glucosamina em cavalos

Estudo da excreção urinária de condroitim sulfato após administração intramuscular da associação de condroitim sulfato e glucosamina em cavalos

Bioactive Compounds from Mimosa pudica Leaves Extract with Their α- glucosidase and Protein Tyrosine Phosphatase 1B Inhibitory Activities in vitro and in silico Approaches

<p>Background: Mimosa pudica Linn has been used in traditional medicine to support the treatment of type 2 diabetes. In the present study, we aimed to isolate and evaluate α-glucosidase and Protein Tyrosine Phosphatase 1B (PTP1B) inhibitory activities of bioactive compounds from Mimosa pudica’s leaf extract. <p> Methods: Mimosa pudica leaves were extracted with 80% of ethanol. Bioactive compounds were isolated using a column chromatographic technique and elucidated the structure based on the nuclear magnetic resonance and electrospray ionization mass spectrometry spectral data. The α- glucosidase and PTP1B inhibitory activities of the isolated compounds were evaluated using pnitrophenyl phosphate and p-nitrophenyl-α-D-glucopyranoside as a substrate, respectively. Molecular docking and molecular dynamics are used to study the interaction between isolated compounds and proteins. Lipinski’s rule of five was used to evaluate the drug-like properties of isolated compounds. Predict pharmacokinetic parameters were evaluated using the pkCSM tool. <p> Results: Protocatechuic acid and syringic acid were isolated and identified using spectroscopic methods. Protocatechuic acid and syringic acid considerably inhibited α-glucosidase enzyme at IC<sub>50</sub> values of 416.17 ± 9.41 μM and 490.78 ± 9.28 μM, respectively. Furthermore, protocatechuic acid and syringic acid expressed strong PTP1B inhibitory activity at IC<sub>50</sub> values of 248.83 ± 7.66 μM and 450.31 ± 7.77 μM, respectively. Molecular docking and molecular dynamics results showed the interactions of protocatechuic acid and syringic acid with amino acids of PTP1B and α-glucosidase enzyme. Lipinski’s rule of five and absorption, distribution, metabolism, excretion, and toxicity studies predicted that protocatechuic acid and syringic acid have drug-likeness properties. In molecular docking simulation, protocatechuic acid and syringic acid gave relatively negative free binding energies and interacted with many amino acids in the active sites of PTP1B and α-glucosidase. The molecular dynamics simulation results of the complexes were also relatively stable. <p> Conclusion: Our results showed that protocatechuic and syringic acids could be promising compounds for type 2 diabetes treatment.</p>

New indole derivatives as multitarget anti-Alzheimer's agents: synthesis, biological evaluation and molecular dynamics.

Background: Alzheimer's disease is a neurological disorder that causes brain cells to shrink and die. Aim: Thirteen novel 'oxathiolanyl', 'pyrazolyl'and 'pyrimidinyl'indole derivatives were designed and synthesized as anti-Alzheimer's disease treatment. Method: In vitro enzyme assay was performed against both AChE and BChE enzymes. In addition, antioxidant assay and cytotoxicity on a normal cell line were determined. Molecular docking and dynamic simulations were conducted to confirm the binding mode in both esterases' active sites. In silico absorption, distribution, metabolism, excretion and toxicity studies were also carried out. Results & conclusion: Compounds 5, 7 and 11 exhibited superior inhibitory activity against acetylcholinesterase and butyrylcholinesterase, with IC50 values of 0.042 and 3.003μM, 2.54 and 0.207μM and 0.052 and 2.529μM, respectively, compared with donepezil.

Designing of thiazolidinones against chicken pox, monkey pox, and hepatitis viruses: A computational approach

Computational designing of four different series (D-G) of thiazolidinone was done starting from different amines which was further condensed with various aldehydes. These underwent in silico molecular investigations for density functional theory (DFT), molecular docking, and absorption, distribution metabolism, excretion, and toxicity (ADMET) studies. The different electrochemical parameters of the compounds are predicted using quantum mechanical modeling approach with Gaussian. The docking software was used to dock the compounds against choosing PDB file for chickenpox, human immunodeficiency, hepatitis, and monkeypox virus as 1OSN, 1VZV, 6VLK, 1RTD, 3I7H, 3TYV, 4JU3, and 4QWO, respectively. The molecular interactions were visualized with discovery studio and maximum binding affinity was observed with D8 compounds against 4QWO (-13.383 kcal/mol) while for compound D5 against 1VZV which was −12.713 kcal/mol. Swiss ADME web tool was used to assess the drug-likeness of the designed compounds under consideration, and it is concluded that these molecules had a drug-like structure with almost zero violations.

Non-regulated LC-MS/MS bioanalysis in support of early drug development: a Novartis perspective.

Scientifically qualified LC-MS/MS methods are essential for the determination of small molecule drug candidates and/or their metabolite(s) in support of various non-regulated safety assessment and in vivo absorption, distribution, metabolism and excretion studies in preclinical development. This articleoutlines an effective method development workflow to fit for this purpose. The workflow features a 'universal' protein precipitation solvent for efficient sample extraction, a mobile phase additive for managing chromatographic resolution and addressing carryoverand an internal standard cocktail to select the best analogue internal standard to track the analyte of interest in LC-MS/MS. In addition, good practices arerecommended to prevent bioanalytical pitfalls due to instability, non-specific bindingand dosing vehicle-induced matrix effect. Proper handling of non-liquid matrix isalso discussed.

Using innovative tools for in vitro absorption, distribution, metabolism and excretion studies to efficiently and effectively support drug development.

Drug development is a complicated and lengthy process requiring a significant amount of intellectual and capital input, as well as extensive collaborations among various organizations and institutions. Contract research organizations play important roles at some or even all stages of the drug development process. To provide better service in in vitro drug absorption, disposition, metabolism and excretion studies, maintain data accuracy and promote work efficiency, we developed an integrated information system termed the 'Drug Metabolism Information System', and it is being used routinely by our drug metabolism department. The Drug Metabolism Information System assists scientists with assay design, data analysis and report drafting and thus reduces human error.

Application of Accelerator Mass Spectrometry to Characterize the Mass Balance Recovery and Disposition of AZD4831, a Novel Myeloperoxidase Inhibitor, following Administration of an Oral Radiolabeled Microtracer Dose in Humans.

This study evaluated the mass balance and disposition of AZD4831, a novel myeloperoxidase inhibitor, in six healthy participants using a 14C-labeled microtracer coupled with analysis by accelerator mass spectrometry (AMS). A single oral dose of 10 mg 14C-AZD4831 (14.8 kBq) was administered as a solution, and 14C levels were quantified by AMS in blood, urine, and feces over 336 hours postdose. AZD4831 was rapidly absorbed, and AZD4831 plasma concentrations declined in a biphasic manner, with a long half-life of 52 hours. AZD4831 was eliminated via metabolism and renal excretion. An N-carbamoyl glucuronide metabolite of AZD4831 (M7), formed primarily via UGT1A1, was the predominant circulating metabolite. Presumably, M7 contributed to the long half-life of AZD4831 via biliary elimination and hydrolysis/enterohepatic recirculation of AZD4831. On average, ∼84% of administered 14C-AZD4831 was recovered by 336 hours postdose (urine, 51.2%; feces, 32.4%). Between 32%-44% of the dose was excreted as unchanged AZD4831 in urine, indicating renal elimination as the major excretory route. Only 9.7% of overall fecal recovery was recorded in the first 48 hours, with the remainder excreted over 48%-336 hours, suggesting that most fecal recovery was due to biliary elimination. Furthermore, only 6% of unchanged AZD4831 was recovered in feces. Overall, the fraction of the administered AZD4831 dose absorbed was high. 14C-AZD4831 was well tolerated. These findings contribute to increasing evidence that human absorption, distribution, metabolism, and excretion studies can be performed with acceptable mass balance recovery at therapeutically relevant doses and low radiolabel-specific activity using an AMS-14C microtracer approach. SIGNIFICANCE STATEMENT: In this study, the human absorption, distribution, metabolism, and excretion (hADME) of the novel myeloperoxidase inhibitor AZD4831 was assessed following oral administration. This included investigation of the disposition of M7, the N-carbamoyl glucuronide metabolite. Resolution of challenges highlighted in this study contributes to increasing evidence that hADME objectives can be achieved in a single study for compounds with therapeutically relevant doses and low radiolabel-specific activity by using an AMS-14C microtracer approach, thus reducing the need for preclinical radiolabeled studies.

Zerumbone Protects Rats from Collagen-Induced Arthritis by Inhibiting Oxidative Outbursts and Inflammatory Cytokine Levels.

Rheumatoid arthritis (RA) is an immunocompromised disorder characterized by a marked increase in the synthesis of inflammatory molecules that stimulates the destruction of bones and cartilage. The conventional treatment modalities for RA are associated with adverse side effects and lack sensitivity, suggesting an immediate demand for alternate beneficial therapeutic remedies. The current study sought to understand more about zerumbone's anti-inflammatory properties in diagnosing collagen-induced arthritis (CIA) in experimental animals. The current study observed that zerumbone reduced clinical severity in CIA-induced animals compared to healthy animals. Zerumbone administration significantly decreased (p < 0.001) the concentration of SOD, CAT, GR, and GSH in treatment groups. Zerumbone administration drove down significantly (p < 0.001) the concentration of inflammatory cytokine molecules. Zerumbone was effective in bringing significant changes in levels of MPO, NO, LDH, MMP-8, and ELA. The therapeutic potential of zerumbone was found to be associated with reduced joint destruction and restored normal histology in the cartilage and tissue. Adsorption, distribution, metabolism, excretion, and toxicity studies were used to determine the druglike properties of zerumbone. ProTox-II studies revealed that zerumbone did not possess toxic properties like hepatotoxicity, immunotoxicity, carcinogenicity, mutagenicity, and cytotoxicity. Therefore, the present study evaluated the therapeutic properties of zerumbone in CIA animal models.

Curcumin-Based Heterocycles: Synthesis, Antimicrobial Genotoxicity and Molecular Docking

Curcumin is a natural compound with numerous biological activities and a precursor for many drugs. Development of a convenient one pot synthetic method for synthesizing curcumin-based diazepines and diazoles having antibacterial activities is focussed in this study. A one pot condensation process was developed for synthesizing a novel class of curcumin-based diazoles and diazepines by reacting curcumin with 2-diamino compounds and hydrazines in presence of sulfuric acid as catalyst. IR and 1H NMR were used to characterize the molecular composition of the synthesized curcumin derivatives. The synthesized derivatives were tested for their in vitro antibacterial efficacy against Gram-negative and Gram-positive bacteria. The MIC concentrations ranged from 1.56 to 200 μg/mL. Ampicillin exhibited synergistic effects with compounds C1, C3, C4 and C8. In the genotoxicity test, compound C3 was found to have no effect on the DNA molecules of E. coli strains, suggesting that it is not mutagenic and/or genotoxic. Compound C2 had the strongest interaction with the investigated protein receptor sites when blind molecular docking was conducted on all compounds. Since both H-donating and H-accepting sites of this molecule interact efficiently during the docking. In addition, absorption, distribution, metabolism and excretion (ADME) study showed that compound C2 do not contradict the Lipinski’s rule of drug likeness and showed a low level of passive human gastrointestinal absorption. The results indicated that C2 could be most promising among the studied compounds.

Site-Specific Tritium Labeling at the Predefined Internal Position of the Chemically-Modified RNA

In nucleic acid drug discovery, it is extremely important to develop a technology to understand the distribution in target organs and to trace the degradation process in the body in order to optimize the structure and improve the efficiency of the clinical trial process. Since nucleic acid drugs are essentially metabolically degraded into numerous fragments, labeling at the internal position is preferable to that at the terminus. Due to the high molar specific activity of tritium, various approaches for tritium-labeling have been studied for nucleic acid drugs. Nevertheless, a generally-applicable method for tritium labeling of the internal position of a nucleic acid has not been established. In this study, we have demonstrated a new and efficient method for site-specific tritium labeling of the cytosine base at a predefined internal position in nucleic acid drugs. This method was developed by the chemical modification of the cytosine 4-amino group with the pyridinyl vinyl keto group by the functionality-transfer reaction using the reactive oligodeoxynucleotide (ODN), followed by reduction with NaBT4. Applicability to a variety of chemical structures, such as 5-methyl cytosine, 2'-O-methyl, 2'-fluoro ribose derivatives, Locked/Bridged nucleic acid (LNA/BNA) derivatives, as well as phosphorothioate bonds, has been evidenced using nine oligoribonucleic acid (ORN) substrates. It has been clearly demonstrated that this method is an excellent method for tritium-labeling of nucleic acid with an average conversion efficiency of 74%, an average isolated labeling yield of 60%, and an average specific activity of 61 GBq/mmol. This method is expected to contribute to the preclinical absorption, distribution, metabolism, excretion (ADME) studies of nucleic acid drug candidates.

A Q-marker screening strategy based on ADME studies and systems biology for Chinese herbal medicine, taking Qianghuo Shengshi decoction in treating rheumatoid arthritis as an example.

Chinese herbal medicine (CHM) exhibits a broad spectrum of clinical applications and demonstrates favorable therapeutic efficacy. Nonetheless, elucidating the underlying mechanism of action (MOA) of CHM in disease treatment remains a formidable task due to its inherent characteristics of multi-level, multi-linked, and multi-dimensional non-linear synergistic actions. In recent years, the concept of a Quality marker (Q-marker) proposed by Liu et al. has significantly contributed to the monitoring and evaluation of CHM products, thereby fostering the advancement of CHM research. Within this study, a Q-marker screening strategy for CHM formulas has been introduced, particularly emphasising efficacy and biological activities, integrating absorption, distribution, metabolism, and excretion (ADME) studies, systems biology, and experimental verification. As an illustrative case, the Q-marker screening of Qianghuo Shengshi decoction (QHSSD) for treating rheumatoid arthritis (RA) has been conducted. Consequently, from a pool of 159 compounds within QHSSD, five Q-markers exhibiting significant in vitro anti-inflammatory effects have been identified. These Q-markers encompass notopterol, isoliquiritin, imperatorin, cimifugin, and glycyrrhizic acid. Furthermore, by employing an integrated analysis of network pharmacology and metabolomics, several instructive insights into pharmacological mechanisms have been gleaned. This includes the identification of key targets and pathways through which QHSSD exerts its crucial roles in the treatment of RA. Notably, the inhibitory effect of QHSSD on AKT1 and MAPK3 activation has been validated through western blot analysis, underscoring its potential to mitigate RA-related inflammatory responses. In summary, this research demonstrates the proposed strategy's feasibility and provides a practical reference model for the systematic investigation of CHM formulas.

In Vivo Metabolism of 1,5-Anhydro-d-fructose to 1,5-Anhydro-d-glucitol.

1,5-Anhydro-d-fructose (1,5-AF, saccharide) and 1,5-anhydro-d-glucitol (1,5-AG) converted from 1,5-AF via the glycemic pathway have health benefits. However, this metabolism has not been sufficiently elucidated. To clarify the in vivo metabolism of 1,5-AF to 1,5-AG, porcine (blood kinetics) and human (urinary excretion) studies were conducted. Microminipigs were administrated 1,5-AF orally or intravenously. Blood samples were obtained to analyse the kinetics of 1,5-AF and 1,5-AG. Urine samples were collected from human subjects who had orally ingested 1,5-AF, and the amounts of 1,5-AF and 1,5-AG excreted in the urine were analysed. In blood kinetics analysis, the time to the maximum concentration of 1,5-AF after intravenous administration was 0.5 h, whereas 1,5-AF was not observed after oral administration. The times to the maximum concentration of 1,5-AG after intravenous and oral administration were 1.5 h and 2 h, respectively. In urinary excretion, the concentration of 1,5-AG in urine rapidly increased after the administration of 1,5-AF, peaked at 2 h, whereas 1,5-AF was not detected. 1,5-AF was rapidly metabolized to 1.5-AG in vivo in swine and human.

An in vivo and in silico evaluation of the hepatoprotective potential of Gynura procumbens: A promising agent for combating hepatotoxicity.

The liver, the most important metabolic organ of the body, performs a wide variety of vital functions. Hepatic cell injury occurs by the activation of reactive oxygen species (ROS) that are generated by carbon tetrachloride (CCl4), xenobiotics, and other toxic substances through cytochrome P450-dependent steps resulting from the covalent bond formation with lipoproteins and nucleic acids. Observing the urgent state of hepatotoxic patients worldwide, different medicinal plants and their properties can be explored to combat such free radical damage to the liver. In vivo and in silico studies were designed and conducted to evaluate the antioxidant and hepatoprotective properties of Gynura procumbens in rats. Gynura procumbens leaves were collected and extracted using 70% ethanol. The required chemicals CCl4, standard drug (silymarin), and blood serum analysis kits were stocked. The in vivo tests were performed in 140 healthy Wister albino rats of either sex under well-controlled parameters divided into 14 groups, strictly maintaining Institutional Animal Ethics Committee (IEAC) protocols. For the histopathology study, 10% buffered neutral formalin was used for organ preservation. Later the specimens were studied under a fluorescence microscope. In silico molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies were performed, and the results were analyzed statistically. Gynura procumbens partially negate the deleterious effect of carbon tetrachloride on normal weight gain in rats. The elevated level of serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), creatinine, LDH, total cholesterol (TC), low-density lipoprotein (LDL), triglycerides (TG), malondialdehyde (MDA), deoxyribonucleic acid (DNA) fragmentation ranges, gamma-glutamyl transferase (γ-GT) in CCl4 treated groups were decreased by both standard drug silymarin and G. procumbens leaf extract. We have found significant & highly significant changes statistically for different doses, here p<0.05 & p<0.01, respectively. On the other hand, G. procumbens and silymarin displayed Statistically significant (p<0.05) and high significant(p<0.01) increased levels of HDL, CAT SOD (here p<0.05 & p<0.01 for different doses) when the treatment groups were compared with the disease control group. Because the therapeutic activity imparted by plants and drugs accelerates the movement of the disturbed pathophysiological state toward the healthy state. In the molecular docking analysis, G. procumbens phytoconstituents performed poorly against transforming growth factor-beta 1 (TGF-β1) compared to the control drug silymarin. In contrast, 26 phytoconstituents scored better than the control bezafibrate against peroxisome proliferator-activated receptor alpha (PPAR-α). The top scoring compounds for both macromolecules were observed to form stable complexes in the molecular dynamics simulations. Flavonoids and phenolic compounds performed better than other constituents in providing hepatoprotective activity. It can, thus, be inferred that the extract of G. procumbens showed good hepatoprotective properties in rats.

SARS-CoV-2 main protease targeting potent fluorescent inhibitors: Repurposing thioxanthones.

The coronavirus disease, COVID-19, is the major focus of the whole world due to insufficient treatment options. It has spread all around the world and is responsible for the death of numerous human beings. The future consequences for the disease survivors are still unknown. Hence, all contributions to understand the disease and effectively inhibit the effects of the disease have great importance. In this study, different thioxanthone based molecules, which are known to be fluorescent compounds, were selectively chosen to study if they can inhibit the main protease of SARS-CoV-2 using various computational tools. All candidate ligands were optimized, molecular docking and adsorption, distribution, metabolism, excretion, and toxicity (ADMET) studies were conducted and subsequently, some were subjected to 100 ns molecular dynamics simulations in conjunction with the known antiviral drugs, favipiravir, and hydroxychloroquine. It was found that different functional groups containing thioxanthone based molecules are capable of different intermolecular interactions. Even though most of the studied ligands showed stable interactions with the main protease, para-oxygen-di-acetic acid functional group containing thioxanthone was found to be a more effective inhibitor due to the higher number of intermolecular interactions and higher stability during the simulations.

Design, synthesis and biological evaluation of phenanthridine amide and 1,2,3-triazole analogues against Mycobacterium tuberculosis.

The phenanthridine core exhibits antitubercular activity, according to reports from the literature. Several 1,2,3-triazole-based heterocyclic compounds are well-known antitubercular agents. A series of twenty-five phenanthridine amide and 1,2,3-triazole derivatives are synthesized and analyzed using ESI-MS, 1HNMR, and 13CNMR on the basis of our earlier findings that phenanthridine and 1,2,3-triazoles shown good antitubercular activity. The synthesized phenanthridine amide and 1,2,3-triazole analogues were tested in vitro against Mycobacterium tuberculosis H37Rv and minimum inhibitory concentration (MIC) values were determined utilizing non-replicating and replicating low-oxygen recovery assay (LORA) and microplate Alamar Blue assay (MABA) methodologies. The phenanthridine amide derivative PA-01 had an MIC of 61.31 μM in MABA and 62.09 μM in the LORA technique, showing intense anti-TB activity. Amongst the phenanthridine triazole derivatives, PT-09, with MICs of 41.47 and 78.75 μM against the tested strain of Mtb in both MABA and LORA was the most active one. The final analogues' drug-likeness is predicted using absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies. The most active compounds PA-01 and PT-09 were further subjected to in silico docking studies. Using the Glide module of Schrodinger, molecular docking analysis was carried out to estimate the plausible binding pattern of PA-01 and PT-09 at the active site of Mycobacterial DNA topoisomerase II (PDB code: 5BS8). Further, molecular dynamics studies of PA-01 and PT-09 were also carried out.

Integrated approach for studying bioactive compounds from Cladosporium spp. against estrogen receptor alpha as breast cancer drug target

Cladosporium spp. have been reported for their great diversity of secondary metabolites which represent as a prominent base material for verifying the biological activities. Several bioactive compounds which have antimicrobial, cytotoxic, quorum sensing inhibitory and phytotoxic activities have been isolated from Cladosporium species. Most of them are still needed to be explored for their anticancer properties. Therefore, the present study is focused on screening and identifying the bioactive compounds of Cladosporium spp. for their anticancer activity via the integrated approaches of Molecular Docking (MD), Molecular Dynamics Simulation (MDS) and Density Functional Theory (DFT) studies. A total of 123 bioactive compounds of Cladosporium spp. were explored for their binding affinity with the selected breast cancer drug target receptor such as estrogen receptor alpha (PDB:6CBZ). The Molecular Docking studies revealed that amongst the bioactive compounds screened, Altertoxin X and Cladosporol H showed a good binding affinity of − 10.5 kcal/mol and − 10.3 kcal/mol, respectively, with the estrogen receptor alpha when compared to the reference compound (17upbeta-Estradiol: − 10.2 kcal/mol). The MDS study indicated the stable binding patterns and conformation of the estrogen receptor alpha-Altertoxin X complex in a stimulating environment. In addition, in silico absorption, distribution, metabolism, excretion and toxicity (ADMET) study suggested that Altertoxin X has a good oral bioavailability with a high LD_{50} value of 2.375 mol/kg and did not cause any hepatotoxicity and skin sensitization. In summary, the integrated approaches revealed that Altertoxin X possesses a promising anticancer activity and could serve as a new therapeutic drug for breast cancer treatment.

Screening and identification of potential MERS-CoV papain-like protease (PLpro) inhibitors; Steady-state kinetic and Molecular dynamic studies

MERS-CoV belongs to the coronavirus group. Recent years have seen a rash of coronavirus epidemics. In June 2012, MERS-CoV was discovered in the Kingdom of Saudi Arabia, with 2,591 MERSA cases confirmed by lab tests by the end of August 2022 and 894 deaths at a case-fatality ratio (CFR) of 34.5% documented worldwide. Saudi Arabia reported the majority of these cases, with 2,184 cases and 813 deaths (CFR: 37.2%), necessitating a thorough understanding of the molecular machinery of MERS-CoV. To develop antiviral medicines, illustrative investigation of the protein in coronavirus subunits are required to increase our understanding of the subject. In this study, recombinant expression and purification of MERS-CoV (PLpro), a primary goal for the development of 22 new inhibitors, were completed using a high throughput screening methodology that employed fragment-based libraries in conjunction with structure-based virtual screening. Compounds 2, 7, and 20, showed significant biological activity. Moreover, a docking analysis revealed that the three compounds had favorable binding mood and binding free energy. Molecular dynamic simulation demonstrated the stability of compound 2 (2-((Benzimidazol-2-yl) thio)-1-arylethan-1-ones) the strongest inhibitory activity against the PLpro enzyme. In addition, disubstitutions at the meta and para locations are the only substitutions that may boost the inhibitory action against PLpro. Compound 2 was chosen as a MERS-CoV PLpro inhibitor after passing absorption, distribution, metabolism, and excretion studies; however, further investigations are required.

Computational molecular docking and in silico ADMET prediction studies of pyrazole derivatives as Covid-19 main protease (MPRO) and papain-like protease (PLPRO) inhibitors

ABSTRACT. The inhibition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro) and papain-like protease (PLpro) prevents viral multiplications. Molecular docking, absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies of pyrazole-indole molecules 6a, b, Schiff bases 8a, b, and pyrazolo[1,5-a]pyrimidines 10a, b were performed and done. Based on the molecular docking study verified that the presented structures (6a, 6b, 8a, 8b, 10a, and 10b) give promised attached bonds with the active site in the COVID-19 main protease (Mpro). The results of in silico ADMET prediction study revealed that these compounds may be considered candidates for the discovery or development of new series of COVID-19 drugs.&#x0D; &#x0D; KEY WORDS: Pyrazole, Fused pyrazole, Schiff bases, COVID-19, Molecular docking, Computational studies&#x0D; &#x0D; Bull. Chem. Soc. Ethiop. 2023, 37(2), 449-461. &#x0D; DOI: https://dx.doi.org/10.4314/bcse.v37i2.14