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1.
Saudi Pharm J ; 31(10): 101787, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37766820

RESUMO

Myocardial injury (MI) is an important pathological driver of mortality worldwide., and arises as a result of imbalances between myocardial oxygen demand and supply. In MI, oxidative stress often leads to inflammatory changes and apoptosis. Current therapies for MI are known to cause various adverse effects. Consequently, the development of new therapeutic agents with a reduced adverse event profile is necessary. In this regard, 2-methoxyestradiol (2ME), the metabolic end-product of oestradiol, possesses anti-inflammatory and antioxidant properties. The aim of this research is to assess the impact of 2ME on cardiac injury caused by isoproterenol (ISO) in rats. Animals were separated into six groups; controls, and those receiving 2ME (1 mg/kg), ISO (85 mg/kg), ISO + 2ME (0.25 mg/kg), ISO + 2ME (0.5 mg/kg), and ISO + 2ME (1 mg/kg). 2ME significantly attenuated ISO-induced changes in electrocardiographic changes and the cardiac histological pattern. This compound also decreased lactate dehydrogenase activity, creatine kinase myocardial band and troponin levels. The ability of 2ME to act as an antioxidant was shown by a decrease in malondialdehyde concentration, and the restoration of glutathione levels and superoxide dismutase activity. Additionally, 2ME antagonized inflammation and cardiac cell apoptosis, a process determined to be mediated, at least partially, by suppression of Gal-3/TLR4/MyD88/NF-κB signaling pathway. 2ME offers protection against acute ISO-induced MI in rats and offers a novel therapeutic management option.

2.
Front Pharmacol ; 14: 965284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033643

RESUMO

Background: Dose optimization of vancomycin plays a substantial role in drug pharmacokinetics because of the increased incidence of obesity worldwide. This systematic review was aimed to highlight the current dosing strategy of vancomycin among obese patients. Methods: This systematic review was in concordance with Preferred Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The literature search was carried out on various databases such as Scopus, PubMed/MEDLINE, ScienceDirect and EMBASE using Keywords and MeSH terms related to vancomycin dosing among obese patients. Google Scholar was also searched for additional articles. The English language articles published after January, 2000 were included in this study. The quality of the study was assessed using different assessment tools for cohort, and case reports. Results: A total of 1,029 records were identified. After screening, 18 studies were included for the final review. Of total, twelve studies are retrospective and remaining six are case-control studies. A total of eight studies were conducted in pediatrics while remaining studies were conducted in adult population. Most of the studies reported the dosing interval every 6-8 h. Differences in target trough concentration exist with respect to target ranges. The administration of loading dose (20-25 mg/kg) followed by maintenance dose (15-25 mg/kg) of vancomycin is recommended in adult patients to target therapeutic outcomes. Moreover, a dose of 40-60 mg/kg/day appears appropriate for pediatric patients. Conclusion: The initial dosing of vancomycin based on TBW could be better predictor of vancomycin trough concentration. However, the clinical significance is uncertain. Therefore, more studies are needed to evaluate the dosing strategy of vancomycin in overweight or obese patients.

3.
Front Mol Biosci ; 10: 1123411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911530

RESUMO

Introduction: Klebsiella pneumoniae (K. pneumoniae) and Pseudomonas aeruginosa (P. aeruginosa) are the most common Gram-negative bacteria associated with pneumonia and coinfecting the same patient. Despite their high virulence, there is no effective vaccine against them. Methods: In the current study, the screening of several proteins from both pathogens highlighted FepA and OmpK35 for K. pneumonia in addition to HasR and OprF from P. aeruginosa as promising candidates for epitope mapping. Those four proteins were linked to form a multitope vaccine, that was formulated with a suitable adjuvant, and PADRE peptides to finalize the multitope vaccine construct. The final vaccine's physicochemical features, antigenicity, toxicity, allergenicity, and solubility were evaluated for use in humans. Results: The output of the computational analysis revealed that the designed multitope construct has passed these assessments with satisfactory scores where, as the last stage, we performed a molecular docking study between the potential vaccine construct and K. pneumonia associated immune receptors, TLR4 and TLR2, showing affinitive to both targets with preferentiality for the TLR4 receptor protein. Validation of the docking studies has proceeded through molecular dynamics simulation, which estimated a strong binding and supported the nomination of the designed vaccine as a putative solution for K. pneumoniae and P. aeruginosa coinfection. Here, we describe the approach for the design and assessment of our potential vaccine.

4.
Metabolites ; 13(2)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36837781

RESUMO

Cancer is the leading cause of death globally, with an increasing number of cases being annually reported. Nature-derived metabolites have been widely studied for their potential programmed necrosis, cytotoxicity, and anti-proliferation leading to enrichment for the modern medicine, particularly within the last couple of decades. At a more rapid pace, the concept of multi-target agents has evolved from being an innovative approach into a regular drug development procedure for hampering the multi-fashioned pathophysiology and high-resistance nature of cancer cells. With the advent of the Red Sea Penicillium chrysogenum strain S003-isolated indole-based alkaloids, we thoroughly investigated the molecular aspects for three major metabolites: meleagrin (MEL), roquefortine C (ROC), and isoroquefortine C (ISO) against three cancer-associated biological targets Cdc-25A, PTP-1B, and c-Met kinase. The study presented, for the first time, the detailed molecular insights and near-physiological affinity for these marine indole alkaloids against the assign targets through molecular docking-coupled all-atom dynamic simulation analysis. Findings highlighted the superiority of MEL's binding affinity/stability being quite in concordance with the in vitro anticancer activity profile conducted via sulforhodamine B bioassay on different cancerous cell lines reaching down to low micromolar or even nanomolar potencies. The advent of lengthy structural topologies via the metabolites' extended tetracyclic cores and aromatic imidazole arm permitted multi-pocket accommodation addressing the selectivity concerns. Additionally, the presence decorating polar functionalities on the core hydrophobic tetracyclic ring contributed compound's pharmacodynamic preferentiality. Introducing ionizable functionality with more lipophilic characters was highlighted to improve binding affinities which was also in concordance with the conducted drug-likeness/pharmacokinetic profiling for obtaining a balanced pharmacokinetic/dynamic profile. Our study adds to the knowledge regarding drug development and optimization of marine-isolated indole-based alkaloids for future iterative synthesis and pre-clinical investigations as multi-target anticancer agents.

5.
Molecules ; 28(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677539

RESUMO

Isoquinoline alkaloids constitute one of the most common classes of alkaloids that have shown a pronounced role in curing various diseases. Finding ways to reduce the toxicity of these molecules and to increase their therapeutic margin is an urgent matter. Here, a one-step method for the synthesis of a series of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines was performed in 85-98% yield by the Pictet-Spengler reaction. This was accomplished using the reaction between 3,4-dimethoxyphenylethylamine and substituted benzaldehydes boiling in trifluoroacetic acid. Furthermore, 1-(3'-amino-, 4'-aminophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines were obtained in 94% and 97% yield by reduction in 1-(3'-nitro-, 4'-nitrophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines with SnCl2 × 2H2O. The structures of the substances obtained were confirmed by infrared (IR) and nuclear magnetic resonance (1H and 13C NMR) spectra. ADMET/TOPKAT in silico study concluded that the synthesized compounds exhibited acceptable pharmacodynamic and pharmacokinetic properties without carcinogenic or mutagenic potential but with variable hepatotoxicity. The acute toxicity and structure-toxicity relationship (STR) in the series of 20 derivatives of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines (3a-r, 4a, b) was studied via determination of acute toxicity and resorptive action in white mice employing intragastric step-by-step administration. The first compound, 1-phenyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline hydrochloride (3a), showed the highest toxicity with LD50 of 280 mg/kg in contrast to 1-(3'-bromo -4'-hydroxyphenyl)-6,7-methylenedioxy-1,2,3,4-tetrahydroisoquinoline hydrochloride (3e) which proved to be the safest of the compounds studied. Its toxicity was 13.75 times lower than that of the parent compound 3a. All compounds investigated showed high local anesthetic activity on rabbit eyes in the concentrations studied. Only 3r, 3n, and 4a caused eye irritation and redness. All investigated derivatives (except 4b) in 1% concentration were more active than lidocaine, providing longer duration of complete anesthesia. Therefore, based on the obtained results of in silico tests, local anesthesia, and acute toxicity, a conclusion can be drawn that the experimental compounds need further extensive future investigations and possible modifications so that they can act as promising drug candidates.


Assuntos
Alcaloides , Tetra-Hidroisoquinolinas , Camundongos , Animais , Coelhos , Anestésicos Locais , Anestesia Local , Tetra-Hidroisoquinolinas/toxicidade , Tetra-Hidroisoquinolinas/química , Alcaloides/toxicidade , Dose Letal Mediana
6.
Antioxidants (Basel) ; 12(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36670981

RESUMO

Drug-metabolizing enzymes are either boosted or suppressed by diabetes mellitus. This research was designed to explore Fagonia cretica L. aerial parts' impact on CYP3A4 and UGT2B7 activity and their mRNA expression in diabetic rats. Fagonia cretica (F. cretica) dried powder was sequentially extracted with n-hexane, chloroform, ethyl acetate, methanol, and water. The methanol extract and aqueous fraction presented the most significant potential to decrease the concentration of alpha-hydroxyl midazolam, with 176.0 ± 0.85 mg/Kg and 182.9 ± 0.99 mg/Kg, respectively, compared to the streptozotocin (STZ)-induced diabetic group, reflecting the inhibition in CYP3A4 activity. The fold change in mRNA expression of CYP3A4 was decreased significantly by the methanol extract, and the aqueous fraction of F. cretica estimated by 0.15 ± 0.002 and 0.16 ± 0.001, respectively, compared with the diabetic group. Morphine metabolism was significantly increased in rats treated with F. cretica methanol extract and its aqueous fraction, displaying 93.4 ± 0.96 mg/Kg and 96.4 ± 1.27 mg/Kg, respectively, compared with the metabolism of morphine in the diabetic group, which highlights the induction of UGT2B7 activity. The fold change in mRNA expression of UGT2B7 was significantly increased by the methanol extract and the aqueous fraction, estimated at 8.14 ± 0.26 and 7.17 ± 0.23 respectively, compared to the diabetic group. Phytochemical analysis was performed using high-performance liquid chromatography (HPLC), where the methanol extract showed more flavonoids and phenolic compounds compared to the aqueous fraction of F. cretica. The obtained results were further consolidated by molecular docking studies, where quercetin showed the best fitting within the active pocket of CYP3A4, followed by gallic acid, displaying free binding energies (∆G) of -30.83 and -23.12 kcal/mol, respectively. Thus, F. cretica could serve as a complementary medicine with standard anti-diabetic therapy that can modulate the activity of the drug-metabolizing enzymes.

7.
Pharmacol Res Perspect ; 10(6): e01031, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36380704

RESUMO

The translation of new injectable anesthetic drugs from rodent to humans remains slow, despite the realization that reliance on the volatile agents is unsustainable from an environmental perspective. The aim of this study was to investigate the influence of rat sex and strain on the PK and PD of the anesthetic neurosteroid alfaxalone. Forty rats had cannulas inserted under isoflurane anesthesia for drug administration and sampling. Carotid artery blood samples were collected for blood gas analysis, hematology, biochemistry, and plasma concentrations of alfaxalone. Plasma samples were assayed using liquid chromatography-mass spectrometry. Compartmental non-linear mixed effects methods (NLME) models were applied to two rat populations to determine whether body weight, sex, and strain influenced PK parameters. There were significant differences between the sexes for plasma clearance, half-life and mean residence time in Lewis rats, and mean arterial blood pressure was significantly lower in the female rats at 120 min. An initial NLME PK population model was used to design an adjusted alfaxalone infusion for SD females matching plasma concentrations in males and minimizing cardiopulmonary depression but maintaining an appropriate hypnotic effect. A final NLME population model showed that alfaxalone clearance was dependent on both bodyweight and sex, whereas volume of distribution was influenced by strain. NLME PK models offer the advantage of having a single model that describes a population and therefore shares data interpretation between animals unlike the standard deterministic PK approach. This approach can be used to propose bespoke dosing regimens for optimal use of alfaxalone.


Assuntos
Anestésicos , Pregnanodionas , Humanos , Masculino , Feminino , Animais , Ratos , Ratos Endogâmicos Lew , Pregnanodionas/farmacologia , Anestésicos/farmacocinética , Meia-Vida
8.
Molecules ; 27(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36235292

RESUMO

Fungus continues to attract great attention as a promising pool of biometabolites. Aspergillus ochraceus Wilh (Aspergillaceae) has established its capacity to biosynthesize a myriad of metabolites belonging to different chemical classes, such as isocoumarins, pyrazines, sterols, indole alkaloids, diketopiperazines, polyketides, peptides, quinones, polyketides, and sesquiterpenoids, revealing various bioactivities that are antimicrobial, cytotoxic, antiviral, anti-inflammatory, insecticidal, and neuroprotective. Additionally, A. ochraceus produces a variety of enzymes that could have variable industrial and biotechnological applications. From 1965 until June 2022, 165 metabolites were reported from A. ochraceus isolated from different sources. In this review, the formerly separated metabolites from A. ochraceus, including their bioactivities and biosynthesis, in addition, the industrial and biotechnological potential of A. ochraceus are highlighted.


Assuntos
Anti-Infecciosos , Policetídeos , Anti-Infecciosos/metabolismo , Anti-Inflamatórios/metabolismo , Antivirais , Aspergillus ochraceus , Dicetopiperazinas/metabolismo , Alcaloides Indólicos/metabolismo , Isocumarinas/metabolismo , Peptídeos/metabolismo , Policetídeos/metabolismo , Pirazinas/metabolismo , Quinonas/metabolismo , Esteróis/metabolismo
9.
Antioxidants (Basel) ; 11(7)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35883740

RESUMO

This study presents a comparison between two mistletoe plants-P. acacia and P. curviflorus-regarding their total phenolic contents and antioxidant and anticancer activities. P. curviflorus exhibited a higher total phenolics content (340.62 ± 19.46 mg GAE/g extract), and demonstrated higher DPPH free radical scavenging activity (IC50 = 48.28 ± 3.41µg/mL), stronger reducing power (1.43 ± 0.54 mMol Fe+2/g) for ferric ions, and a greater total antioxidant capacity (41.89 ± 3.15 mg GAE/g) compared to P. acacia. The cytotoxic effects of P. acacia and P. curviflorus methanol extracts were examined on lung (A549), prostate (PC-3), ovarian (A2780) and breast (MDA-MB-231) cancer cells. The highest anticancer potential for the two extracts was observed on PC-3 prostate cancer cells, where P. curviflorus exhibited more pronounced antiproliferative activity (IC50 = 25.83 µg/mL) than P. acacia (IC50 = 34.12 µg/mL). In addition, both of the tested extracts arrested the cell cycle at the Pre-G1 and G1 phases, and induced apoptosis. However, P. curviflorus extract possessed the highest apoptotic effect, mediated by the upregulation of p53, Bax, and caspase-3, 8 and 9, and the downregulation of Bcl-2 expression. In the pursuit to link the chemical diversity of P. curviflorus with the exhibited bioactivities, its metabolomic profiling was achieved by the LC-ESI-TOF-MS/MS technique. This permitted the tentative identification of several phenolics-chiefly flavonoid derivatives, beside some triterpenes and sterols-in the P. curviflorus extract. Furthermore, all of the metabolites in P. curviflorus and P. acacia were inspected for their binding modes towards both CDK-2 and EGFR proteins using molecular docking studies in an attempt to understand the superiority of P. curviflorus over P. acacia regarding their antiproliferative effect on PC-3 cancer cells. Docking studies supported our experimental results; with all of this taken together, P. curviflorus could be regarded as a potential prospect for the development of chemotherapeutics for prostate cancer.

10.
J Vet Pharmacol Ther ; 45(1): 46-53, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34469007

RESUMO

Hydroxyzine and cetirizine are first- and second-generation oral antihistamine drugs, respectively, used to treat allergic reactions in horses. Cetirizine is also a metabolite of hydroxyzine, which may lead to complexities in regulating their use in equine sporting events. The aim of the research was to be able to provide detection times (DT) from pharmacokinetic studies in thoroughbred horses to better inform trainers, and their veterinary surgeons, prescribing these substances for treatment of Thoroughbred racehorses. Six and two horses were given 9 repeated administrations of hydroxyzine HCl (500 mg BID) or cetirizine HCl (190 mg BID), respectively. Plasma and urine hydroxyzine and cetirizine concentrations were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A holistic non-linear mixed effects PK model was developed that described both plasma and urine concentrations of hydroxyzine and cetirizine, either from administration of each individually or cetirizine as a metabolite of hydroxyzine. Using the parameters obtained from this PK model in conjunction with methodology developed by Toutain afforded possible screening limits (SL) that can regulate for a DT of 4 days in either plasma or urine. Hydroxyzine and cetirizine concentration prediction intervals for the 80th , 95th and 99th percentiles of a virtual horse population were performed in order to assess the statistical protection of the DT. However, it is down to the individual racing authorities to apply their own risk management.


Assuntos
Hidroxizina , Preparações Farmacêuticas , Administração Oral , Animais , Cetirizina , Cromatografia Líquida/veterinária , Antagonistas dos Receptores Histamínicos H1 , Cavalos , Espectrometria de Massas em Tandem/veterinária
11.
Front Microbiol ; 13: 1078061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687608

RESUMO

Introduction: Diabetes mellitus is a chronic metabolic disorder that exhibited great expansion all over the world. It is becoming an epidemic disease adding a major burden to the health care system, particularly in developing countries. Methods: The plant under investigation in the current study Phragmanthera austroarabica A. G. Mill and J. A. Nyberg is traditionally used in Saudi Arabia for the treatment of diabetes mellitus. The methanolic extract (200 mg/kg) of the plant and pure gallic acid (40 mg/kg), a major metabolite of the plant, as well as their silver nanoparticle formulae (AgNPs) were evaluated for their antidiabetic activity. Results and Discussion: The results showed a decrease in body fat, obesity, an improvement in lipid profiles, normalization of hyperglycemia, insulin resistance, and hyperinsulinemia, and an improvement in liver tissue structure and function. However, the results obtained from AgNPs for both extract and the pure gallic acid were better in most measured parameters. Additionally, the activity of both the crude extract of the plant and its AgNPs were evaluated against a number of gram-positive, gram-negative bacteria and fungi. Although the activity of the crude extract ranged from moderate to weak or even non-active, the AgNPs of the plant extract clearly enhanced the antimicrobial activity. AgNPs of the extract demonstrated remarkable activity, especially against the Gram-negative pathogens Proteus vulgaris (MIC 2.5 µg/ml) and Pseudomonas aeruginosa (MIC 5 µg/ml). Furthermore, a promising antimicrobial activity was shown against the Gram-positive pathogen Streptococcus mutants (MIC 1.25 µg/ml).

12.
Xenobiotica ; 50(10): 1220-1227, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32369392

RESUMO

Horses are exposed to various kinds of medication, however, there are limited determinations of plasma clearance (CLp) for the drugs used due to the high cost of equine in vivo studies.Many of the CLp values generated come from the equine sports industry for determining drug plasma screening limits in the control of medications at the time of competition.The kinetics of omeprazole metabolism were investigated in freshly isolated and cryopreserved equine hepatocytes and hepatic microsomes (n = 3 horses).The Vmax, Km and intrinsic clearance (CLint) of omeprazole were determined via the substrate depletion method as well as Km values for the formation of three metabolites.The CLint values were extrapolated to in vivo hepatic plasma clearance (CLH) using the well stirred and parallel tube models.Clp for omeprazole was successfully predicted using freshly isolated or cryopreserved equine hepatocytes, while microsomes under-predicted.Equine microsomes were used to perform a drug-drug interaction (DDI) study between omeprazole and chloramphenicol. The average inhibitor constant Ki, assuming competitive inhibition, was 15.4 ± 5 µM.To the authors' knowledge, this is the first report showing the successful extrapolation of drug CLp in the horse using equine hepatocytes and the prediction of a DDI using microsomes.


Assuntos
Cavalos/metabolismo , Omeprazol/metabolismo , Animais , Criopreservação , Interações Medicamentosas , Hepatócitos , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Omeprazol/farmacologia
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