scholarly journals A novel nucleoside rescue metabolic pathway may be responsible for therapeutic effect of orally administered cordycepin

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jong Bong Lee ◽  
Masar Radhi ◽  
Elena Cipolla ◽  
Raj D. Gandhi ◽  
Sarir Sarmad ◽  
...  

Abstract Although adenosine and its analogues have been assessed in the past as potential drug candidates due to the important role of adenosine in physiology, only little is known about their absorption following oral administration. In this work, we have studied the oral absorption and disposition pathways of cordycepin, an adenosine analogue. In vitro biopharmaceutical properties and in vivo oral absorption and disposition of cordycepin were assessed in rats. Despite the fact that numerous studies showed efficacy following oral dosing of cordycepin, we found that intact cordycepin was not absorbed following oral administration to rats. However, 3′-deoxyinosine, a metabolite of cordycepin previously considered to be inactive, was absorbed into the systemic blood circulation. Further investigation was performed to study the conversion of 3′-deoxyinosine to cordycepin 5′-triphosphate in vitro using macrophage-like RAW264.7 cells. It demonstrated that cordycepin 5′-triphosphate, the active metabolite of cordycepin, can be formed not only from cordycepin, but also from 3′-deoxyinosine. The novel nucleoside rescue metabolic pathway proposed in this study could be responsible for therapeutic effects of adenosine and other analogues of adenosine following oral administration. These findings may have importance in understanding the physiology and pathophysiology associated with adenosine, as well as drug discovery and development utilising adenosine analogues.

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 175
Author(s):  
Dong-Gyun Han ◽  
Eunju Cha ◽  
Jeongmin Joo ◽  
Ji Sun Hwang ◽  
Sanghyun Kim ◽  
...  

Acacetin, an important ingredient of acacia honey and a component of several medicinal plants, exhibits therapeutic effects such as antioxidative, anticancer, anti-inflammatory, and anti-plasmodial activities. However, to date, studies reporting a systematic investigation of the in vivo fate of orally administered acacetin are limited. Moreover, the in vitro physicochemical and biopharmaceutical properties of acacetin in the gastrointestinal (GI) tract and their pharmacokinetic impacts remain unclear. Therefore, in this study, we aimed to systematically investigate the oral absorption and disposition of acacetin using relevant rat models. Acacetin exhibited poor solubility (≤119 ng/mL) and relatively low stability (27.5–62.0% remaining after 24 h) in pH 7 phosphate buffer and simulated GI fluids. A major portion (97.1%) of the initially injected acacetin dose remained unabsorbed in the jejunal segments, and the oral bioavailability of acacetin was very low at 2.34%. The systemic metabolism of acacetin occurred ubiquitously in various tissues (particularly in the liver, where it occurred most extensively), resulting in very high total plasma clearance of 199 ± 36 mL/min/kg. Collectively, the poor oral bioavailability of acacetin could be attributed mainly to its poor solubility and low GI luminal stability.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2505
Author(s):  
Raheem Remtulla ◽  
Sanjoy Kumar Das ◽  
Leonard A. Levin

Phosphine-borane complexes are novel chemical entities with preclinical efficacy in neuronal and ophthalmic disease models. In vitro and in vivo studies showed that the metabolites of these compounds are capable of cleaving disulfide bonds implicated in the downstream effects of axonal injury. A difficulty in using standard in silico methods for studying these drugs is that most computational tools are not designed for borane-containing compounds. Using in silico and machine learning methodologies, the absorption-distribution properties of these unique compounds were assessed. Features examined with in silico methods included cellular permeability, octanol-water partition coefficient, blood-brain barrier permeability, oral absorption and serum protein binding. The resultant neural networks demonstrated an appropriate level of accuracy and were comparable to existing in silico methodologies. Specifically, they were able to reliably predict pharmacokinetic features of known boron-containing compounds. These methods predicted that phosphine-borane compounds and their metabolites meet the necessary pharmacokinetic features for orally active drug candidates. This study showed that the combination of standard in silico predictive and machine learning models with neural networks is effective in predicting pharmacokinetic features of novel boron-containing compounds as neuroprotective drugs.


2021 ◽  
Vol 22 (15) ◽  
pp. 7844
Author(s):  
Jason S. Holsapple ◽  
Ben Cooper ◽  
Susan H. Berry ◽  
Aleksandra Staniszewska ◽  
Bruce M. Dickson ◽  
...  

Extracorporeal Shock Wave Therapy (ESWT) is used clinically in various disorders including chronic wounds for its pro-angiogenic, proliferative, and anti-inflammatory effects. However, the underlying cellular and molecular mechanisms driving therapeutic effects are not well characterized. Macrophages play a key role in all aspects of healing and their dysfunction results in failure to resolve chronic wounds. We investigated the role of ESWT on macrophage activity in chronic wound punch biopsies from patients with non-healing venous ulcers prior to, and two weeks post-ESWT, and in macrophage cultures treated with clinical shockwave intensities (150–500 impulses, 5 Hz, 0.1 mJ/mm2). Using wound area measurements and histological/immunohistochemical analysis of wound biopsies, we show ESWT enhanced healing of chronic ulcers associated with improved wound angiogenesis (CD31 staining), significantly decreased CD68-positive macrophages per biopsy area and generally increased macrophage activation. Shockwave treatment of macrophages in culture significantly boosted uptake of apoptotic cells, healing-associated cytokine and growth factor gene expressions and modulated macrophage morphology suggestive of macrophage activation, all of which contribute to wound resolution. Macrophage ERK activity was enhanced, suggesting one mechanotransduction pathway driving events. Collectively, these in vitro and in vivo findings reveal shockwaves as important regulators of macrophage functions linked with wound healing. This immunomodulation represents an underappreciated role of clinically applied shockwaves, which could be exploited for other macrophage-mediated disorders.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jiyuan Yan ◽  
Yingchi Zhang ◽  
Gaohong Sheng ◽  
Bowei Ni ◽  
Yifan Xiao ◽  
...  

Osteoarthritis (OA) is a prevalent degenerative joint disease. Its development is highly associated with inflammatory response and apoptosis in chondrocytes. Selonsertib (Ser), the inhibitor of Apoptosis Signal-regulated kinase-1 (ASK1), has exhibited multiple therapeutic effects in several diseases. However, the exact role of Ser in OA remains unclear. Herein, we investigated the anti-arthritic effects as well as the potential mechanism of Ser on rat OA. Our results showed that Ser could markedly prevent the IL-1β-induced inflammatory reaction, cartilage degradation and cell apoptosis in rat chondrocytes. Meanwhile, the ASK1/P38/JNK and NFκB pathways were involved in the protective roles of Ser. Furthermore, intra-articular injection of Ser could significantly alleviate the surgery induced cartilage damage in rat OA model. In conclusion, our work provided insights into the therapeutic potential of Ser in OA, indicating that Ser might serve as a new avenue in OA treatment.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4011-4011 ◽  
Author(s):  
Paul W. Manley ◽  
Jürgen Mestan ◽  
Jennifer Sheng ◽  
Phi Tran ◽  
Mark Kagan

Abstract Background There is a growing tendency for drugs to be grouped according to their perceived ‘class effects’, regardless of the different pharmacological profiles of the parent drugs and of their metabolites. Imatinib, dasatinib, nilotinib, bosutinib and, most recently ponatinib, are approved tyrosine kinase inhibitor (TKI) therapies for chronic myeloid leukemia (CML), which are clinically efficacious as a result of ABL1/ BCR-ABL inhibition. Following their oral administration at standard therapeutic doses, the parent drugs are the major circulating species by area under the curve (AUC). However in the case of imatinib, dasatinib, bosutinib and ponatinib, the exposure of patients to major metabolites can be substantial compared to that of parent drug, with CGP74588 (which is much less active than imatinib against both BCR-ABL and KIT; Bioorg Med Chem 2013;21:3231) representing 10% of imatinib by AUC (Clin Pharmacokinet 2005;44:879); M20 and M24 representing 45 and 25% of dasatinib (Drug Met Disp 2008;36:1341), M2 and M5 representing 19 and 25% of bosutinib (Clinical Pharmacology Biopharmaceutics Review, http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm) and AP24600 representing 58% of ponatinib (Clinical Pharmacology Biopharmaceutics Review, http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm). Such major metabolites might make significant contributions to the on- and off-target effects of the parent drugs in vivoand may be responsible for some of the side-effects observed in patients. Here we report on the metabolism of the potent and selective BCR-ABL inhibitor, nilotinib and the preclinical profile of its major metabolites. Methods The metabolism of nilotinib was characterised in healthy subjects after oral administration of two capsules containing 200 mg [14C]-labelled nilotinib (50 μCi), and blood plasma, feces and urine samples were assayed in an appropriate scintillant either by counting an aliquot directly or after homogenisation, air-drying and solubilisation. Metabolites were characterised and quantified by HPLC with radioactivity detection and identified by mass spectrometry (LC-MS/MS) and, when possible, co-elution with non-radiolabeled authentic samples. Synthesised samples of the metabolites were evaluated in a large panel of assays for potential effects on kinase and non-kinase enzymes, G-protein coupled receptors, cell transporters, ion channels and nuclear receptors. Results The oral absorption of nilotinib was determined to be ≥30% and excretion was mainly into the feces (93.5% of administered radioactivity), with neither nilotinib nor the identified metabolites being detected in the urine. Unchanged nilotinib was the major circulating component in human plasma, accounting for 87.5±9.2% of the total drug-related AUC. The main circulating metabolites were P41.6 (4.7% AUC), P36.5 (6.1% AUC), formed from oxidation of the methyl group in the methyl-imidazole moiety to a hydroxyl or carboxylic acid group, and P42.1 (1.3% AUC) resulting from oxidation of the phenyl-methyl group. Other, more minor metabolites included the pyridine N-oxide P36 and P50, resulting from degradation of the imidazole. All of the metabolites identified in humans were also observed in one or more of the animal species, employed for preclinical safety studies, with the exception of the minor fecal metabolites P38 (pyridine- + pyrimidine-N-oxide) and P40 (pyridine-N-oxide). In comparison to the parent nilotinib, which inhibits the BCR-ABL and KIT tyrosine kinases with mean cellular IC50 values of 20 and 217 nM, only P41.6 (19 and 284 nM), P42.1 (256 and 714 nM) and P50 (39 and 67 nM) exhibited kinase inhibition at concentrations < 2200 nM. In addition, none of the metabolites showed substantial activity at concentrations < 3000 nM against non-kinase targets. Conclusion Following oral administration of nilotinib to humans the predominant circulating species was the parent drug, with >15 minor and trace metabolites being identified. Given their in vitro potencies and target profiles, none of the metabolites are expected to contribute to the in vivo pharmacology of the parent nilotinib. This data further distinguishes the profile of nilotinib from other TKIs used for the treatment of CML. Disclosures: Manley: Novartis Pharmaceuticals: Employment. Sheng:Novartis Pharmaceuticals: Employment. Tran:Novartis Pharmaceuticals: Employment. Kagan:Novartis Pharmaceuticals: Employment.


2021 ◽  
Author(s):  
William C Carlquist ◽  
Eric N Cytrynbaum

The patterns formed both in vivo and in vitro by the Min protein system have attracted much interest because of the complexity of their dynamic interactions given the apparent simplicity of the component parts. Despite both the experimental and theoretical attention paid to this system, the details of the biochemical interactions of MinD and MinE, the proteins responsible for the patterning, are still unclear. For example, no model consistent with the known biochemistry has yet accounted for the observed dual role of MinE in the membrane stability of MinD. Until now, a statistical comparison of models to the time course of Min protein concentrations on the membrane has not been carried out. Such an approach is a powerful way to test existing and novel models that are difficult to test using a purely experimental approach. Here, we extract time series from previously published fluorescence microscopy time lapse images of in vitro experiments and fit two previously described and one novel mathematical model to the data. We find that the novel model, which we call the Asymmetric Activation with Bridged Stability Model, fits the time-course data best. It is also consistent with known biochemistry and explains the dual MinE role via MinE-dependent membrane stability that transitions under the influence of rising MinE to membrane instability with positive feedback. Our results reveal a more complex network of interactions between MinD and MinE underlying Min-system dynamics than previously considered.


Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1580 ◽  
Author(s):  
Vuanghao Lim ◽  
Edward Schneider ◽  
Hongli Wu ◽  
Iok-Hou Pang

Cataract is an eye disease with clouding of the eye lens leading to disrupted vision, which often develops slowly and causes blurriness of the eyesight. Although the restoration of the vision in people with cataract is conducted through surgery, the costs and risks remain an issue. Botanical drugs have been evaluated for their potential efficacies in reducing cataract formation decades ago and major active phytoconstituents were isolated from the plant extracts. The aim of this review is to find effective phytoconstituents in cataract treatments in vitro, ex vivo, and in vivo. A literature search was synthesized from the databases of Pubmed, Science Direct, Google Scholar, Web of Science, and Scopus using different combinations of keywords. Selection of all manuscripts were based on inclusion and exclusion criteria together with analysis of publication year, plant species, isolated phytoconstituents, and evaluated cataract activities. Scientists have focused their attention not only for anti-cataract activity in vitro, but also in ex vivo and in vivo from the review of active phytoconstituents in medicinal plants. In our present review, we identified 58 active phytoconstituents with strong anti-cataract effects at in vitro and ex vivo with lack of in vivo studies. Considering the benefits of anti-cataract activities require critical evaluation, more in vivo and clinical trials need to be conducted to increase our understanding on the possible mechanisms of action and the therapeutic effects.


2017 ◽  
Vol 312 (5) ◽  
pp. L599-L608 ◽  
Author(s):  
Sherry E. Adesina ◽  
Brandy E. Wade ◽  
Kaiser M. Bijli ◽  
Bum-Yong Kang ◽  
Clintoria R. Williams ◽  
...  

Pulmonary hypertension (PH) is characterized by increased pulmonary vascular resistance, pulmonary vascular remodeling, and increased pulmonary vascular pressures that often result in right ventricular dysfunction, leading to right heart failure. Evidence suggests that reactive oxygen species (ROS) contribute to PH pathogenesis by altering pulmonary vascular cell proliferation and intracellular signaling pathways. However, the role of mitochondrial antioxidants and oxidant-derived stress signaling in the development of hypoxia-induced PH is largely unknown. Therefore, we examined the role of the major mitochondrial redox regulator thioredoxin 2 (Trx2). Levels of Trx2 mRNA and protein were examined in human pulmonary arterial endothelial cells (HPAECs) and smooth muscle cells (HPASMCs) exposed to hypoxia, a common stimulus for PH, for 72 h. Hypoxia decreased Trx2 mRNA and protein levels. In vitro overexpression of Trx2 reduced hypoxia-induced H2O2 production. The effects of increased Trx2 protein level were examined in transgenic mice expressing human Trx2 (TghTrx2) that were exposed to hypoxia (10% O2) for 3 wk. TghTrx2 mice exposed to hypoxia had exacerbated increases in right ventricular systolic pressures, right ventricular hypertrophy, and increased ROS in the lung tissue. Trx2 overexpression did not attenuate hypoxia-induced increases in Trx2 oxidation or Nox4 expression. Expression of a dominant negative C93S Trx2 mutant that mimics Trx2 oxidation exacerbated hypoxia-induced increases in HPASMC H2O2 levels and cell proliferation. In conclusion, Trx2 overexpression failed to attenuate hypoxia-induced HPASMC proliferation in vitro or hypoxia-induced PH in vivo. These findings indicate that strategies to enhance Trx2 expression are unlikely to exert therapeutic effects in PH pathogenesis.


2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Xiaofan Lai ◽  
Shaojie Huang ◽  
Sijia Lin ◽  
Lvya Pu ◽  
Yaqing Wang ◽  
...  

Abstract Background Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive deadly fibrotic lung disease with high prevalence and mortality worldwide. The therapeutic potential of mesenchymal stem cells (MSCs) in pulmonary fibrosis may be attributed to the strong paracrine, anti-inflammatory, anti-apoptosis and immunoregulatory effects. However, the mechanisms underlying the therapeutic effects of MSCs in IPF, especially in terms of alveolar type 2 (AT2) cells senescence, are not well understood. The purpose of this study was to evaluate the role of MSCs in NAD metabolism and senescence of AT2 cells in vitro and in vivo. Methods MSCs were isolated from human bone marrow. The protective effects of MSCs injection in pulmonary fibrosis were assessed via bleomycin mouse models. The senescence of AT2 cells co-cultured with MSCs was evaluated by SA-β-galactosidase assay, immunofluorescence staining and Western blotting. NAD+ level and NAMPT expression in AT2 cells affected by MSCs were determined in vitro and in vivo. FK866 and NAMPT shRNA vectors were used to determine the role of NAMPT in MSCs inhibiting AT2 cells senescence. Results We proved that MSCs attenuate bleomycin-induced pulmonary fibrosis in mice. Senescence of AT2 cells was alleviated in MSCs-treated pulmonary fibrosis mice and when co-cultured with MSCs in vitro. Mechanistic studies showed that NAD+ and NAMPT levels were rescued in AT2 cells co-cultured with MSCs and MSCs could suppress AT2 cells senescence mainly via suppressing lysosome-mediated NAMPT degradation. Conclusions MSCs attenuate AT2 cells senescence by upregulating NAMPT expression and NAD+ levels, thus exerting protective effects in pulmonary fibrosis.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 556-556 ◽  
Author(s):  
Maulin Mukeshchandra Patel ◽  
Robert Silasi-Mansat ◽  
Ravi Shankar Keshari ◽  
Christopher L. Sansam ◽  
David A. Jones ◽  
...  

Abstract We used in vitro and in vivo models to characterize the physiological role of the novel protein encoded by C6ORF105. This gene's expression is androgen-responsive, and the encoded protein is predicted to be palmitoylated and membrane multi-spanning. Previously we showed that C6ORF105 expression co-regulates with tissue factor pathway inhibitor (TFPI)in human endothelial cells (EC); hence we named this protein "androgen-dependent TFPI-regulating protein" (ADTRP). Using in vitro cell-based TOP-Flash reporter assay we identified ADTRP as a negative regulator of canonical Wnt signaling in human cells. Overexpressing ADTRP in HEK293T cells inhibited the activity of beta-catenin/TCF-dependent transcriptional reporter, while silencing ADTRP increased the expression of Wnt target genes LEF-1, AXIN-2, IL-8 and DKK-2 in EA.hy926 EC line and HUVEC. Addition of LiCl showed that the effect of ADTRP was upstream of GSK3, therefore we focused the investigations on the Wnt signalosome proteins. ADTRP expression in HEK293T cells led to decreased phosphorylation of Wnt co-receptor LRP6, suggesting that ADTRP can affect this critical membrane-located event of Wnt signaling. Furthermore, ADTRP expression in reporter cells transfected with a constitutively phosphorylated form of LRP6 (LRP6DN mutant) inhibited Wnt3a- induced signaling, which suggests that ADTRP can interfere with events downstream of LRP6 phosphorylation, such as Axin-2 binding. Altogether, these data indicate that the Wnt signaling inhibitory activity of ADTRP takes place at the plasma membrane level. Site directed mutagenesis of the predicted palmitoylation site Cys61 showed that Wnt inhibitory effects of ADTRP require palmitoyl-mediated anchoring, highlighting the importance of proper membrane location of ADTRP for Wnt pathway inhibition. In vivo morpholino-based knockdown of adtrp in zebrafish embryos produced aberrant angiogenesis, defective branching and ruptured vessels, hemorrhage spots, pericardial edema and slow heart-beat, all reminiscent of defects caused by activation of canonical Wnt signaling. Indeed, adtrp knock down increased Wnt mediated lef-1 and pax-2a as well as mmp2 and mmp9 mRNA expression. Co-injection of ADTRP mRNA partially recovered the adtrp morpholino- induced morphologic abnormalities. Also, knock down of adtrp in a Wnt reporter zebrafish showed increased expression of ectopic Wnt signaling. Furthermore, our recently established Adtrp-/- mice also display some typical Wnt-mediated vascular defects, including: (i) abnormal patterning, increased capillary tortuosity, abnormal branching and increased density of the capillary network; (ii) dilated vessels, especially venules and veins; (iii) increased leakeage of permeability tracers (Evans blue and fluorescent dextran) without evident changes in endothelial junctions; (iv) hemorrhage spots in the skin, meningeal layers, heart, bladder and kidneys; (v) intravascular and interstitial fibrin deposition in the lung, liver and kidney. ADTRP deficiency decreased plasma TFPI antigen by ~2-times. Furthermore, TFPI antigen and anticoagulant activity in lung extracts and isolated lung EC were similarly decreased, which confirms our previous in vitro data. We aslo noticed increased tail bleeding time (>500 sec vs. 200 sec in WT littermates) and blood volume loss, which likely was caused by increased dilation of the tail vein. Gene expression analysis of whole organs showed upregulation of Wnt target genes involved in vascular contractility (Nos3), and extracellular matrix remodeling (Mmp2). Similarly, skin fibroblasts and lung EC isolated from Adtrp-/- mice showed increased expression of Wnt target genes (Lef-1, Cyclin D, Dkk2, c-Myc), which indicates constitutive activation of canonical Wnt signaling. In conclusion, we used genetic animal models and cell culture systems to show for the first time that the novel protein ADTRP plays major roles in vascular development and function. Lack of, or low levels of ADTRP associate with activation of coagulation and vascular development defects, which may be due, at least in part, to intrinsic high levels of ectopic canonical Wnt signaling. Disclosures No relevant conflicts of interest to declare.


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