Current Drug Metabolism - Volume 24, Issue 4, 2023

Monkeypox is a zoonotic viral disease and remains endemic in tropical regions of Central and West Africa. Since May of 2022, cases of monkeypox have soared and spread worldwide. Confirmed cases have shown no travel history to the endemic regions as seen in the past. The World Health Organization declared monkeypox a global public health emergency in July 2022, and the United States government followed suit one month later. The current outbreak, in contrast to traditional epidemics, has high coinfection rates, particularly with HIV (human immunodeficiency virus), and to a lesser extent with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the pathogen of COVID-19. No drugs have been approved specifically for monkeypox. However, there are therapeutic agents authorized to treat monkeypox under the Investigational New Drug protocol, including brincidofovir, cidofovir, and tecovirimat. In contrast to limited options for monkeypox treatment, there are available drugs specifically for HIV or SARS-CoV-2 infection. Interestingly, these HIV and COVID-19 medicines share metabolism pathways with those authorized to treat monkeypox, particularly of hydrolysis, phosphorylation, and active membrane transport. This review discusses how these pathways shared by these medicines should be considered to gain therapeutic synergy and maximize safety for treating monkeypox coinfections.

For the brain to operate normally and to develop with structural integrity in addition to neuronal function, blood-brain barrier present in brain capillaries serves as a vital barrier mechanism. In addition to the transport barrier created by membranes, transporters, and vesicular processes, the structure and function of the BBB are summarised. The physical barrier is created by endothelial tight junctions. The permeability and transport of molecules between extracellular fluid and plasma are constrained by the presence of tight junctions between neighbouring endothelial cells. Each solute must pass through both membranes in the luminal and abluminal divisions. The functions of the neurovascular unit are described, with special emphasis on the pericytes, microglia, and astrocyte endfeet. The luminal membrane contains five separate facilitative transport mechanisms, each of which is exclusive to a few substrates. Nevertheless, the import of big-branched and aromatic neutral amino acids is facilitated by two key carriers (System L and y+) in the plasma membrane. It is asymmetrically present in both membranes. The sodium pump Na⁺/K⁺-ATPase is highly expressed in the abluminal membrane, where many Na⁺ dependent transport mechanisms move amino acids against its concentration gradient. The trojan horse strategy, which uses molecular tools to bind the medication and its formulations, is also preferred in drug delivery. The BBB's cellular structure, the transport systems unique to each substrate, and the necessity to identify transporters with changes that assist the transfer of various medications have all been changed in the current work. Nevertheless, to rule out the BBB passage for the new class of neuroactive medications, the mixing of traditional pharmacology and nanotechnology needs to be focused on outcomes that show promise.

Background: Polygonatum sibiricum polysaccharide (PSP) can improve insulin resistance and inhibit oxidative stress. However, the detailed anti-diabetic mechanism of PSP is still poorly defined. Methods: In this study, the anti-diabetic, anti-inflammatory and anti-oxidative effects of PSP were evaluated on a type 2 diabetes mellitus (T2DM) rat model. Furthermore, we investigated the changes in gut microbiota and serum metabolites in T2DM rats after PSP treatment through 16S rRNA sequencing and untargeted metabolomics analyses. Results: Our results showed that PSP exhibited significant anti-diabetic, anti-inflammatory and anti-oxidative effects on T2DM model rats. In addition, 16S rRNA sequencing showed that PSP treatment decreased the Firmicutes/ Bacteroidetes ratio in the gut. At the genus level, PSP treatment increased the relative abundances of Blautia, Adlercreutzia, Akkermansia and Parabacteroides while decreasing Prevotella, Megamonas funiformis and Escherichia. Untargeted metabolomics analysis revealed that PSP treatment could affect 20 metabolites, including hexanoylglycine, (±)5(6)-DiHET, ecgonine, L-cysteine-S-sulfate, epitestosterone, (±)12(13)-DiHOME, glutathione, L-ornithine, Dmannose 6-phosphate, L-fucose, L-tryptophan, L-kynurenine, serotonin, melatonin, 3-hydroxyanthranilic acid, xylitol, UDP-D-glucuronate, hydroxyproline, 4-guanidinobutyric acid, D-proline in T2DM model rats, these metabolites are associated with arginine and proline metabolism, tryptophan metabolism, amino sugar and nucleotide sugar metabolism, pentose and glucuronate interconversions, glutathione metabolism, arginine biosynthesis, ascorbate and aldarate metabolism pathways. Spearman correlation analysis results showed that the modulatory effects of PSP on the arginine and proline metabolism, tryptophan metabolism, and glutathione metabolism pathways were related to the regulation of Prevotella, Megamonas funiformis, Escherichia, Blautia and Adlercreutzia. Conclusion: Our research revealed the therapeutic, anti-inflammatory and anti-oxidative effects of PSP on T2DM. The mechanisms of PSP on T2DM are associated with improving the dysbiosis of gut microbiota and regulating arginine and proline metabolism, tryptophan metabolism, and glutathione metabolism in serum.

Background and Objective: Protein kinases known as mitogen-activated protein kinases (MAPKs) are responsible for regulating a wide variety of physiological cell responses by generating and release of inflammatory mediators. Suppressing these inflammatory mediators can be utilized to control the propagation of inflammation. During the course of this research, we created folate-targeted MK2 inhibitor conjugates and analyzed the antiinflammatory effects of these compounds. Methods: Using RAW264.7 cells, which are generated from murine macrophages, as an in vitro model. We synthesize and evaluated a folate linked peptide MK2 inhibitor. The cytotoxicity was assessed using the ELISA kits, CCK- 8 test kit, NO concentration and inflammatory factors TNF-, IL-1, and IL-6. Results: The cytotoxicity assay results suggested that the concentration for MK2 inhibitors less than 50.0 μM be non-toxic. The ELISA Kits also demonstrated that MK2 peptide inhibitor treatment significantly decreased the content of NO, TNF-, IL-1, and IL-6 in LPS-stimulated RAW264.7 cells. It was also demonstrated that a folate-targeted MK2 inhibitor was more effective than a non-targeted inhibitor. Conclusion: This experiment demonstrates that LPS-induced macrophages can produce oxidative stress and inflammatory mediators. According to our research, pro-inflammatory mediators can be reduced by targeting folate receptor- positive (FR+) macrophages with an FR-linked anti-inflammatory MK2 peptide inhibitor in vitro, and the uptake was FR-specific.

Background: Sanwujiao pill (SWJP) is a Chinese herbal preparation widely used in China. It is an essential medicine for treating rheumatism and blood stasis. However, its safety in clinical use has always been the focus of patients because it contains toxic herbs of Aconitum carmichaelii Debx. and A. vilmorinianum Kom. Objective: To further reveal the pharmaceutical and toxic effect substances and the action mechanism of SWJPs, the metabolites and their pathways of ten Aconitum alkaloids (AAs) in the preparation at different time points after oral administration in eight organs of mice were investigated. Method: The biosamples were investigated by a four-step strategy of UPLC-Q-TOF-MS /MS technology. Results: Aconitine (AC), mesaconitine (MA), and hypaconitine (HA) were not detected in any organs. The highest concentrations of the other seven AAs occurred at 0.5 h. Yunaconitine (YAC) was not detected in the brain; all seven AAs had the lowest concentration in the brain, and the metabolism was slow in the stomach. Twelve predicted metabolites were identified, the kidney and stomach were their primary distribution locations, and the most metabolites were found at 0.5h. The main metabolic pathways of the ten AAs were demethylation, deethylation, deoxygenation, hydroxylation, and deacetylation. Conclusion: This is the first report about the metabolism of ten AAs in SWJPs in mice. Significantly, the metabolic pathways and products of four hidden toxic AAs were analyzed in vivo for the first time. The results were of great significance for the safety and effectiveness of SWJPs in clinical application.

Background: Scoparone, the principal natural active ingredient of Artemisia capillaries (Yin Chen), can effectively treat cholestatic diseases, but the pharmacokinetic properties of scoparone are rarely studied in intrahepatic cholestatic rats. Objective: A sensitive and rapid LC-MS/MS method was established to detect scoparone and its metabolite of scopoletin in rat plasma and then compare their plasma pharmacokinetic differences between the normal and ANITinduced cholestasis rats. Methods: Positive ionization was used to separate scoparone and scopoletin using acetonitrile and 0.1 % formic acid water as the mobile phase on a Hypersil ODS-BP column. Results: The calibration curves presented good linearity (R=0.9983 and 0.9989) in the concentration range of 10- 10000 ng/mL and 0.5-500 ng/mL for scoparone and scopoletin, respectively. The precision of ≤ 9.4% and the accuracy ranged from -6.4% to 6.8% were recorded over three validation runs, and the recovery was higher than 83.9%. Under different storage conditions, scoparone and scopoletin were stable. Therefore, we studied the pharmacokinetic properties of scoparone and scopoletin in rats after a single oral administration with the above method. According to the results, the pharmacokinetic parameters of AUC, t1/2, and Cmax values of scoparone in the ANIT group were increased by 106%, 75%, and 44%, respectively, while these values of scopoletin were increased by 142%, 62%, and 65%. Conclusion: The findings indicated that the pharmacokinetic properties of scoparone and scopoletin were significantly different between the normal and ANIT-induced cholestasis rats, which suggested that the clinical application dosage of scoparone should be adjusted according to the liver function of patients.