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1.
Stem Cell Res Ther ; 15(1): 189, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956646

ABSTRACT

BACKGROUND: Recent studies have proved the role of autophagy in mesenchymal stem cell (MSCs) function and regenerative properties. How and by which mechanism autophagy modulation can affect the juxtacrine interaction of MSCs should be addressed. Here, the role of autophagy was investigated in the formation of tunneling nanotubes (TNTs) and homotypic mitochondrial donation. METHODS: MSCs were incubated with 15 µM Metformin (Met) and/or 3 µM 3-methyladenine (3-MA) for 48 h. The formation of TNTs was assessed using bright-field and SEM images. The mitochondria density and ΔΨ values were monitored using flow cytometry analysis. Using RT-PCR and protein array, the close interaction and shared mediators between autophagy, apoptosis, and Wnt signaling pathways were also monitored. The total fatty acid profile was assessed using gas chromatography. RESULT: Data indicated the increase of TNT length and number, along with other cell projections after the induction of autophagy while these features were blunted in 3-MA-treated MSCs (p < 0.05). Western blotting revealed the significant reduction of Rab8 and p-FAK in 3-MA-treated MSCs (p < 0.05), indicating the inhibition of TNT assembly and vesicle transport. Likewise, the stimulation of autophagy increased autophagic flux and mitochondrial membrane integrity compared to 3-MA-treated MSCs. Despite these findings, protein levels of mitochondrial membrane Miro1 and 2 were unchanged after autophagy inhibition/stimulation (p > 0.05). We found that the inhibition/stimulation of autophagy can affect the protein, and transcription levels of several mediators related to Wnt and apoptosis signaling pathways involved in different cell bioactivities. Data confirmed the profound increase of mono and polyunsaturated/saturated fatty acid ratio in MSCs exposed to autophagy stimulator. CONCLUSIONS: In summary, autophagy modulation could affect TNT formation which is required for homotypic mitochondrial donation. Thus, the modulation of autophagy creates a promising perspective to increase the efficiency of cell-based therapies.


Subject(s)
Autophagy , Mesenchymal Stem Cells , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/cytology , Mitochondria/metabolism , Adenine/pharmacology , Adenine/analogs & derivatives , Humans , Nanotubes/chemistry , Apoptosis/drug effects , Animals , Metformin/pharmacology , Cells, Cultured , Wnt Signaling Pathway/drug effects , Cell Membrane Structures
2.
J Med Case Rep ; 18(1): 315, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38982482

ABSTRACT

BACKGROUND: Central nervous system involvement in chronic lymphocytic leukemia rarely occurs, and there is no standard therapy for central nervous system involvement in chronic lymphocytic leukemia. This article aims to analyze the diagnosis and treatment of central nervous system involvement in chronic lymphocytic leukemia. CASE PRESENTATION: It reports two cases of central nervous system involvement in chronic lymphocytic leukemia describing the clinical course, therapy, and prognosis. Case 1 is a 67-year-old Asian male patient, he experienced complications with central nervous system involvement after developing resistance to ibrutinib, bendamustine, and rituximab (BR) chemotherapies. The central nervous system lesion was controlled with high-dose methotrexate combined with pomalidomide, but Richter transformation occurred several months later. Case 2 is a 62-year-old Asian female patient, she had central nervous system involvement at initial diagnosis, and bone marrow and central nervous system lesions were controlled by ibrutinib therapy. CONCLUSION: Central nervous system involvement in chronic lymphocytic leukemia is rare and can be diagnosed on the basis of clinical features, cerebrospinal fluid testing, and radiographic evaluation. Ibrutinib, pomalidomide, and other drugs that can cross the blood-brain barrier may be effective for treating central nervous system involvement in chronic lymphocytic leukemia.


Subject(s)
Adenine , Leukemia, Lymphocytic, Chronic, B-Cell , Piperidines , Thalidomide , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Aged , Male , Female , Middle Aged , Adenine/analogs & derivatives , Piperidines/therapeutic use , Thalidomide/therapeutic use , Thalidomide/analogs & derivatives , Central Nervous System Neoplasms/drug therapy , Central Nervous System Neoplasms/secondary , Central Nervous System Neoplasms/diagnostic imaging , Pyrazoles/therapeutic use , Methotrexate/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pyrimidines/therapeutic use
3.
Nutrients ; 16(13)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38999878

ABSTRACT

Resveratrol, acting as a prebiotic, and propionate, functioning as a postbiotic, hold promise for preventing hypertension in chronic kidney disease (CKD). Previously, we employed propionate to enhance the bioavailability of resveratrol through esterification, resulting in the production of a resveratrol propionate ester (RPE) mixture. In this study, we purified 3-O-propanoylresveratrol (RPE2) and 3,4'-di-O-propanoylresveratrol (RPE4) and investigated their protective effects in a juvenile rat adenine-induced CKD model. To this end, male Sprague Dawley rats aged three weeks (n = 40) were divided into five groups: control; CKD (rats fed adenine); CKRSV (CKD rats treated with 50 mg/L resveratrol); CDRPE2 (CKD rats treated with 25 mg/L RPE2); and CKRPE4 (CKD rats treated with 25 mg/L RPE 4). RPE2 and PRE4 similarly exhibited blood pressure-lowering effects comparable to those of resveratrol, along with increased nitric oxide (NO) availability. Furthermore, RPE2 and RPE4 positively influenced plasma short-chain fatty acid (SCFA) levels and induced distinct alterations in the gut microbial composition of adenine-fed juvenile rats. The supplementation of RPE2 and RPE4, by restoring NO, elevating SCFAs, and modulating the gut microbiota, holds potential for ameliorating CKD-induced hypertension.


Subject(s)
Adenine , Antihypertensive Agents , Blood Pressure , Dietary Supplements , Gastrointestinal Microbiome , Hypertension , Rats, Sprague-Dawley , Renal Insufficiency, Chronic , Resveratrol , Animals , Gastrointestinal Microbiome/drug effects , Resveratrol/pharmacology , Male , Adenine/pharmacology , Antihypertensive Agents/pharmacology , Blood Pressure/drug effects , Rats , Hypertension/drug therapy , Propionates , Nitric Oxide/metabolism , Fatty Acids, Volatile/metabolism , Disease Models, Animal , Diet
4.
Nat Commun ; 15(1): 5613, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965236

ABSTRACT

Advancements in CRISPR technology, particularly the development of base editors, revolutionize genetic variant research. When combined with model organisms like zebrafish, base editors significantly accelerate and refine in vivo analysis of genetic variations. However, base editors are restricted by protospacer adjacent motif (PAM) sequences and specific editing windows, hindering their applicability to a broad spectrum of genetic variants. Additionally, base editors can introduce unintended mutations and often exhibit reduced efficiency in living organisms compared to cultured cell lines. Here, we engineer a suite of adenine base editors (ABEs) called ABE-Ultramax (Umax), demonstrating high editing efficiency and low rates of insertions and deletions (indels) in zebrafish. The ABE-Umax suite of editors includes ABEs with shifted, narrowed, or broadened editing windows, reduced bystander mutation frequency, and highly flexible PAM sequence requirements. These advancements have the potential to address previous challenges in disease modeling and advance gene therapy applications.


Subject(s)
Adenine , CRISPR-Cas Systems , Gene Editing , INDEL Mutation , Zebrafish , Zebrafish/genetics , Animals , Gene Editing/methods , Adenine/metabolism , RNA, Guide, CRISPR-Cas Systems/genetics , RNA, Guide, CRISPR-Cas Systems/metabolism , Animals, Genetically Modified , Alleles
5.
Molecules ; 29(11)2024 May 28.
Article in English | MEDLINE | ID: mdl-38893418

ABSTRACT

A set of 2-aryl-9-H or methyl-6-morpholinopurine derivatives were synthesized and assayed through radioligand binding tests at human A1, A2A, A2B, and A3 adenosine receptor subtypes. Eleven purines showed potent antagonism at A1, A3, dual A1/A2A, A1/A2B, or A1/A3 adenosine receptors. Additionally, three compounds showed high affinity without selectivity for any specific adenosine receptor. The structure-activity relationships were made for this group of new compounds. The 9-methylpurine derivatives were generally less potent but more selective, and the 9H-purine derivatives were more potent but less selective. These compounds can be an important source of new biochemical tools and/or pharmacological drugs.


Subject(s)
Purinergic P1 Receptor Antagonists , Humans , Structure-Activity Relationship , Purinergic P1 Receptor Antagonists/pharmacology , Purinergic P1 Receptor Antagonists/chemistry , Receptors, Purinergic P1/metabolism , Molecular Structure , Adenine/analogs & derivatives , Adenine/chemistry , Adenine/pharmacology , Morpholines/chemistry , Morpholines/pharmacology , Purines/chemistry , Purines/pharmacology , Purines/chemical synthesis , CHO Cells
6.
Eur J Pharmacol ; 977: 176675, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38825303

ABSTRACT

BACKGROUND: Ibrutinib, a Bruton's tyrosine kinase inhibitor used in cancer therapy, exerts ventricular proarrhythmic effects; however, the underlying mechanisms remain unclear. Excitation-contraction coupling (E-C) disorders are pivotal for the genesis of ventricular arrhythmias (VAs), which arise mainly from the right ventricular outflow tract (RVOT). In this study, we aimed to comprehensively investigate whether ibrutinib regulates the electromechanical activities of the RVOT, leading to enhanced arrhythmogenesis, and explore the underlying mechanisms. METHODS: We utilized conventional microelectrodes to synchronously record electrical and mechanical responses in rabbit RVOT tissue preparations before and after treatment with ibrutinib (10, 50, and 100 nM) and investigated their electromechanical interactions and arrhythmogenesis during programmed electrical stimulation. The fluorometric ratio technique was used to measure intracellular calcium concentration in isolated RVOT myocytes. RESULTS: Ibrutinib (10-100 nM) shortened the action potential duration. Ibrutinib at 100 nM significantly increased pacing-induced ventricular tachycardia (VT) (from 0% to 62.5%, n = 8, p = 0.025). Comparisons between pacing-induced VT and non-VT episodes demonstrated that VT episodes had a greater increase in contractility than that of non-VT episodes (402.1 ± 41.4% vs. 232.4 ± 29.2%, p = 0.003). The pretreatment of ranolazine (10 µM, a late sodium current blocker) prevented the occurrence of ibrutinib-induced VAs. Ibrutinib (100 nM) increased late sodium current, reduced intracellular calcium transients, and enhanced calcium leakage in RVOT myocytes. CONCLUSION: Ibrutinib increased the risk of VAs in the RVOT due to dysregulated electromechanical responses, which can be attenuated by ranolazine or apamin.


Subject(s)
Action Potentials , Adenine , Agammaglobulinaemia Tyrosine Kinase , Piperidines , Protein Kinase Inhibitors , Animals , Piperidines/pharmacology , Rabbits , Adenine/analogs & derivatives , Adenine/pharmacology , Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Agammaglobulinaemia Tyrosine Kinase/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/adverse effects , Action Potentials/drug effects , Pyrimidines/pharmacology , Arrhythmias, Cardiac/chemically induced , Arrhythmias, Cardiac/physiopathology , Male , Heart Ventricles/drug effects , Heart Ventricles/physiopathology , Calcium/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Tachycardia, Ventricular/physiopathology , Pyrazoles/pharmacology , Excitation Contraction Coupling/drug effects
7.
Am J Case Rep ; 25: e941165, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38943241

ABSTRACT

BACKGROUND SARS-CoV-2 infection can persist in immunocompromised patients with hematological malignancies, despite antiviral treatment. This report is of a 67-year-old man with chronic lymphocytic leukemia (CLL), secondary hypogammaglobulinemia, and thrombocytopenia on maintenance therapy with ibrutinib, with persistent SARS-CoV-2 infection unresponsive to antiviral treatment, including remdesivir, nirmatrelvir/ritonavir (Paxlovid), and tixagevimab/cilgavimab (Evusheld). CASE REPORT The patient was admitted to our hospital 3 times. During his first hospitalization, he was treated with 5-day course of remdesivir and intravenous steroids; however, antigen and molecular nasopharyngeal swabs were persistently positive, and he was discharged home. Due to respiratory worsening, he was rehospitalized, and despite being treated initially with tixagevimab/cilgavimab, and subsequently with a remdesivir course of 5 days, SARS-CoV-2 tests remained persistently positive. During his third hospital stay, our patient was subjected to combined therapy with remdesivir and nirmatrelvir/ritonavir for 5 days, obtaining a significant reduction of viral load at both antigen and molecular testing. As an ultimate attempt to achieve a negative status before discharge, a 10-day course of combined remdesivir and nirmatrelvir/ritonavir was administered, with a temporary reduction of viral load, followed by a sudden increase immediately after the discontinuation of Paxlovid. Due to worsening hematological disease and bacterial over-infections, the patient gradually worsened until death. CONCLUSIONS This is an emblematic case of correlation between persistent SARS-CoV-2 infection and immunosuppression status in hematological hosts. In these patients, the viral load remains high, favoring the evolution of the virus, and the immunodeficiency makes it difficult to identify the appropriate therapeutic approach.


Subject(s)
Adenine , COVID-19 , Leukemia, Lymphocytic, Chronic, B-Cell , Piperidines , Humans , Male , Aged , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/complications , Adenine/analogs & derivatives , Adenine/therapeutic use , COVID-19/diagnosis , Piperidines/therapeutic use , Antiviral Agents/therapeutic use , COVID-19 Drug Treatment , SARS-CoV-2 , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/therapeutic use , Alanine/analogs & derivatives , Alanine/therapeutic use , Immunocompromised Host , Maintenance Chemotherapy
8.
HIV Res Clin Pract ; 25(1): 2339576, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38831550

ABSTRACT

BACKGROUND: Weight gain has been well-described with integrase strand transfer inhibitors (INSTIs) and tenofovir alafenamide (TAF). Doravirine (DOR) has been identified as a relatively "weight-neutral" drug; however, there is little data describing its effect on weight change in routine clinical practice. METHODS: We conducted a retrospective chart review of weight change among people with HIV changing from an INSTI- to a non-INSTI regimen with DOR. RESULTS: At the time of ART switch, among 49 people with HIV, the mean age was 47 years, 24% were female, and 75% had HIV-1 viral load <200 copies/mL. Most (55%) people with HIV were taking bictegravir/TAF/emtricitabine prior to the switch. Although 84% switched due to concerns about weight gain, only 16% had a weight gain of ≥10% in the year preceding, and 49% had no substantial change in weight. 86% switched to DOR/lamivudine/tenofovir disoproxil fumarate. A weight decrease (-2.6% [95% CI: -5.1, -0.1%, p = .041] was seen over the year following the ART switch. Weight change prior to switch was greatest in the year 2021 compared to 2019, 2020, and 2022. CONCLUSIONS: Overall, modest changes in weight were seen following ART switch from INSTI-based regimen to a DOR-based, non-INSTI regimen. Further investigations with larger people with HIV cohorts will be helpful to guide clinical practice, while the impact of the COVID-19 pandemic on weight change should also be considered.


Subject(s)
Alanine , HIV Infections , Pyridones , Tenofovir , Weight Gain , Humans , Female , Middle Aged , Male , Retrospective Studies , Tenofovir/therapeutic use , Tenofovir/analogs & derivatives , HIV Infections/drug therapy , HIV Infections/virology , Pyridones/therapeutic use , Adult , Alanine/therapeutic use , Alanine/analogs & derivatives , Weight Gain/drug effects , Anti-HIV Agents/therapeutic use , Viral Load/drug effects , Drug Substitution , Aminobutyrates/therapeutic use , HIV Integrase Inhibitors/therapeutic use , HIV-1/drug effects , Adenine/analogs & derivatives , Adenine/therapeutic use , Triazoles
9.
J Am Heart Assoc ; 13(12): e032357, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38842296

ABSTRACT

BACKGROUND: We recently demonstrated that acute administration of ibrutinib, a Bruton's tyrosine kinase inhibitor used in chemotherapy for blood malignancies, increases ventricular arrhythmia (VA) vulnerability. A pathway of ibrutinib-induced vulnerability to VA that can be modulated for cardioprotection remains unclear. METHODS AND RESULTS: The effects of ibrutinib on cardiac electrical activity and Ca2+ dynamics were investigated in Langendorff-perfused hearts using optical mapping. We also conducted Western blotting analysis to evaluate the impact of ibrutinib on various regulatory and Ca2+-handling proteins in rat cardiac tissues. Treatment with ibrutinib (10 mg/kg per day) for 4 weeks was associated with an increased VA inducibility (72.2%±6.3% versus 38.9±7.0% in controls, P<0.002) and shorter action potential durations during pacing at various frequencies (P<0.05). Ibrutinib also decreased heart rate thresholds for beat-to-beat duration alternans of the cardiac action potential (P<0.05). Significant changes in myocardial Ca2+ transients included lower amplitude alternans ratios (P<0.05), longer times-to-peak (P<0.05), and greater spontaneous intracellular Ca2+ elevations (P<0.01). We also found lower abundance and phosphorylation of myocardial AMPK (5'-adenosine monophosphate-activated protein kinase), indicating reduced AMPK activity in hearts after ibrutinib treatment. An acute treatment with the AMPK activator 5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside ameliorated abnormalities in action potential and Ca2+ dynamics, and significantly reduced VA inducibility (37.1%±13.4% versus 72.2%±6.3% in the absence of 5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside, P<0.05) in hearts from ibrutinib-treated rats. CONCLUSIONS: VA vulnerability inflicted by ibrutinib may be mediated in part by an impairment of myocardial AMPK activity. Pharmacological activation of AMPK may be a protective strategy against ibrutinib-induced cardiotoxicity.


Subject(s)
AMP-Activated Protein Kinases , Action Potentials , Adenine , Arrhythmias, Cardiac , Piperidines , Pyrazoles , Pyrimidines , Animals , Adenine/analogs & derivatives , Adenine/pharmacology , Piperidines/pharmacology , Action Potentials/drug effects , Pyrimidines/pharmacology , AMP-Activated Protein Kinases/metabolism , Pyrazoles/pharmacology , Male , Arrhythmias, Cardiac/chemically induced , Arrhythmias, Cardiac/metabolism , Arrhythmias, Cardiac/physiopathology , Arrhythmias, Cardiac/prevention & control , Protein Kinase Inhibitors/pharmacology , Heart Rate/drug effects , Isolated Heart Preparation , Calcium/metabolism , Rats , Disease Models, Animal , Rats, Sprague-Dawley , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/enzymology , Myocytes, Cardiac/pathology , Calcium Signaling/drug effects , Time Factors
10.
PLoS One ; 19(6): e0305590, 2024.
Article in English | MEDLINE | ID: mdl-38875261

ABSTRACT

The analysis of nucleic acids is one of the fundamental parts of modern molecular biology and molecular diagnostics. The information collected predominantly depends on the condition of the genetic material. All potential damage induced by oxidative stress may affect the final results of the analysis of genetic material obtained using commonly used techniques such as polymerase chain reaction or sequencing. The aim of this work was to evaluate the effects of high temperature and pH on DNA structure in the context of the occurrence of oxidative damage, using square-wave voltammetry and two independent research protocols. We resulted in visible oxidation damage registered in acidic conditions after the thermal denaturation process (pH 4.7) with changes in the intensity of guanine and adenine signals. However, using phosphate buffer (pH 7.0) for DNA denaturation negatively affected the DNA structure, but without any oxidized derivatives present. This leads to the conclusion that oxidation occurring in the DNA melting process results in the formation of various derivatives of nucleobases, both electrochemically active and inactive. These derivatives may distort the results of molecular tests due to the possibility of forming complementary bonds with various nucleobases. For example, 8-oxoguanine can form pairs with both cytosine and adenine.


Subject(s)
DNA , Nucleic Acid Denaturation , Oxidative Stress , Temperature , DNA/chemistry , DNA/metabolism , Oxidation-Reduction , DNA Damage , Hydrogen-Ion Concentration , Guanine/chemistry , Guanine/analogs & derivatives , Guanine/metabolism , Electrochemical Techniques/methods , Adenine/chemistry
11.
Nat Commun ; 15(1): 5103, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877035

ABSTRACT

Cytosine base editors (CBEs) and adenine base editors (ABEs) enable precise C-to-T and A-to-G edits. Recently, ABE8e, derived from TadA-8e, enhances A-to-G edits in mammalian cells and plants. Interestingly, TadA-8e can also be evolved to confer C-to-T editing. This study compares engineered CBEs derived from TadA-8e in rice and tomato cells, identifying TadCBEa, TadCBEd, and TadCBEd_V106W as efficient CBEs with high purity and a narrow editing window. A dual base editor, TadDE, promotes simultaneous C-to-T and A-to-G editing. Multiplexed base editing with TadCBEa and TadDE is demonstrated in transgenic rice, with no off-target effects detected by whole genome and transcriptome sequencing, indicating high specificity. Finally, two crop engineering applications using TadDE are shown: introducing herbicide resistance alleles in OsALS and creating synonymous mutations in OsSPL14 to resist OsMIR156-mediated degradation. Together, this study presents TadA-8e derived CBEs and a dual base editor as valuable additions to the plant editing toolbox.


Subject(s)
CRISPR-Cas Systems , Cytosine , Gene Editing , Oryza , Plants, Genetically Modified , Gene Editing/methods , Cytosine/metabolism , Oryza/genetics , Solanum lycopersicum/genetics , Adenine/analogs & derivatives , Adenine/metabolism , Herbicide Resistance/genetics , Genome, Plant
12.
Cell Mol Life Sci ; 81(1): 257, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874784

ABSTRACT

Adenine base editors (ABEs), consisting of CRISPR Cas nickase and deaminase, can chemically convert the A:T base pair to G:C. ABE8e, an evolved variant of the base editor ABE7.10, contains eight directed evolution mutations in its deaminase TadA8e that significantly increase its base editing activity. However, the functional implications of these mutations remain unclear. Here, we combined molecular dynamics (MD) simulations and experimental measurements to investigate the role of the directed-evolution mutations in the base editing catalysis. MD simulations showed that the DNA-binding affinity of TadA8e is higher than that of the original deaminase TadA7.10 in ABE7.10 and is mainly driven by electrostatic interactions. The directed-evolution mutations increase the positive charge density in the DNA-binding region, thereby enhancing the electrostatic attraction of TadA8e to DNA. We identified R111, N119 and N167 as the key mutations for the enhanced DNA binding and confirmed them by microscale thermophoresis (MST) and in vivo reversion mutation experiments. Unexpectedly, we also found that the directed mutations improved the thermal stability of TadA8e by ~ 12 °C (Tm, melting temperature) and that of ABE8e by ~ 9 °C, respectively. Our results demonstrate that the directed-evolution mutations improve the substrate-binding ability and protein stability of ABE8e, thus providing a rational basis for further editing optimisation of the system.


Subject(s)
DNA , Directed Molecular Evolution , Gene Editing , Molecular Dynamics Simulation , Mutation , DNA/metabolism , DNA/genetics , DNA/chemistry , Gene Editing/methods , Adenine/metabolism , Adenine/chemistry , Protein Stability , Protein Binding , Static Electricity , CRISPR-Cas Systems/genetics
13.
J Med Chem ; 67(12): 10490-10507, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38845345

ABSTRACT

Building on the preceding structural analysis and a structure-activity relationship (SAR) of 8-aryl-2-hexynyl nucleoside hA2AAR antagonist 2a, we strategically inverted C2/C8 substituents and eliminated the ribose moiety. These modifications aimed to mitigate potential steric interactions between ribose and adenosine receptors. The SAR findings indicated that such inversions significantly modulated hA3AR binding affinities depending on the type of ribose, whereas removal of ribose altered the functional efficacy via hA2AAR. Among the synthesized derivatives, 2-aryl-8-hexynyl adenine 4a demonstrated the highest selectivity for hA2AAR (Ki,hA2A = 5.0 ± 0.5 nM, Ki,hA3/Ki,hA2A = 86) and effectively blocked cAMP production and restored IL-2 secretion in PBMCs. Favorable pharmacokinetic properties and a notable enhancement of anticancer effects in combination with an mAb immune checkpoint blockade were observed upon oral administration of 4a. These findings establish 4a as a viable immune-oncology therapeutic candidate.


Subject(s)
Adenine , Adenosine A2 Receptor Antagonists , Nucleosides , Receptor, Adenosine A2A , Ribose , Humans , Structure-Activity Relationship , Animals , Adenine/pharmacology , Adenine/chemistry , Adenine/analogs & derivatives , Adenosine A2 Receptor Antagonists/pharmacology , Adenosine A2 Receptor Antagonists/chemistry , Adenosine A2 Receptor Antagonists/chemical synthesis , Nucleosides/chemistry , Nucleosides/pharmacology , Nucleosides/chemical synthesis , Ribose/chemistry , Ribose/metabolism , Receptor, Adenosine A2A/metabolism , Mice , Molecular Structure , Rats , Female , Cell Line, Tumor
14.
Cell ; 187(14): 3602-3618.e20, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38823389

ABSTRACT

Purine nucleotides are vital for RNA and DNA synthesis, signaling, metabolism, and energy homeostasis. To synthesize purines, cells use two principal routes: the de novo and salvage pathways. Traditionally, it is believed that proliferating cells predominantly rely on de novo synthesis, whereas differentiated tissues favor the salvage pathway. Unexpectedly, we find that adenine and inosine are the most effective circulating precursors for supplying purine nucleotides to tissues and tumors, while hypoxanthine is rapidly catabolized and poorly salvaged in vivo. Quantitative metabolic analysis demonstrates comparative contribution from de novo synthesis and salvage pathways in maintaining purine nucleotide pools in tumors. Notably, feeding mice nucleotides accelerates tumor growth, while inhibiting purine salvage slows down tumor progression, revealing a crucial role of the salvage pathway in tumor metabolism. These findings provide fundamental insights into how normal tissues and tumors maintain purine nucleotides and highlight the significance of purine salvage in cancer.


Subject(s)
Neoplasms , Purine Nucleotides , Purines , Animals , Mice , Purines/metabolism , Purines/biosynthesis , Neoplasms/metabolism , Neoplasms/pathology , Purine Nucleotides/metabolism , Humans , Inosine/metabolism , Hypoxanthine/metabolism , Mice, Inbred C57BL , Adenine/metabolism , Cell Line, Tumor , Female
15.
Calcif Tissue Int ; 115(2): 174-184, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38856730

ABSTRACT

Patients with chronic kidney disease (CKD) report high pain levels, but reduced renal clearance eliminates many analgesic options; therefore, 30-50% of CKD patients have chronic opioid prescriptions. Opioid use in CKD is associated with higher fracture rates. Opioids may directly alter bone turnover directly through effects on bone cells and indirectly via increasing inflammation. We hypothesized that continuous opioid exposure would exacerbate the high bone turnover state of CKD and be associated with elevated measures of inflammation. Male C57Bl/6J mice after 8 weeks of adenine-induced CKD (AD) and non-AD controls (CON) had 14-day osmotic pumps (0.25-µL/hr release) containing either saline or 50-mg/mL oxycodone (OXY) surgically implanted in the subscapular region. After 2 weeks, all AD mice had elevated blood urea nitrogen, parathyroid hormone, and serum markers of bone turnover compared to controls with no effect of OXY. Immunohistochemical staining of the distal femur showed increased numbers of osteocytes positive for the mu opioid and for toll-like receptor 4 (TLR4) due to OXY. Osteocyte protein expression of tumor necrosis factor-α (TNF-α) and RANKL were higher due to both AD and OXY so that AD + OXY mice had the highest values. Trabecular osteoclast-covered surfaces were also significantly higher due to both AD and OXY, resulting in AD + OXY mice having 4.5-fold higher osteoclast-covered surfaces than untreated CON. These data demonstrate that opioids are associated with a pro-inflammatory state in osteocytes which increases the pro-resorptive state of CKD.


Subject(s)
Adenine , Analgesics, Opioid , Disease Models, Animal , Mice, Inbred C57BL , Osteoclasts , Renal Insufficiency, Chronic , Animals , Adenine/pharmacology , Adenine/adverse effects , Male , Renal Insufficiency, Chronic/chemically induced , Renal Insufficiency, Chronic/metabolism , Osteoclasts/drug effects , Osteoclasts/metabolism , Analgesics, Opioid/adverse effects , Mice , Inflammation , Bone Remodeling/drug effects , Oxycodone/pharmacology , Bone and Bones/metabolism , Bone and Bones/drug effects
16.
N Engl J Med ; 390(23): 2143-2155, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38899693

ABSTRACT

BACKGROUND: The identification of oncogenic mutations in diffuse large B-cell lymphoma (DLBCL) has led to the development of drugs that target essential survival pathways, but whether targeting multiple survival pathways may be curative in DLBCL is unknown. METHODS: We performed a single-center, phase 1b-2 study of a regimen of venetoclax, ibrutinib, prednisone, obinutuzumab, and lenalidomide (ViPOR) in relapsed or refractory DLBCL. In phase 1b, which included patients with DLBCL and indolent lymphomas, four dose levels of venetoclax were evaluated to identify the recommended phase 2 dose, with fixed doses of the other four drugs. A phase 2 expansion in patients with germinal-center B-cell (GCB) and non-GCB DLBCL was performed. ViPOR was administered every 21 days for six cycles. RESULTS: In phase 1b of the study, involving 20 patients (10 with DLBCL), a single dose-limiting toxic effect of grade 3 intracranial hemorrhage occurred, a result that established venetoclax at a dose of 800 mg as the recommended phase 2 dose. Phase 2 included 40 patients with DLBCL. Toxic effects that were observed among all the patients included grade 3 or 4 neutropenia (in 24% of the cycles), thrombocytopenia (in 23%), anemia (in 7%), and febrile neutropenia (in 1%). Objective responses occurred in 54% of 48 evaluable patients with DLBCL, and complete responses occurred in 38%; complete responses were exclusively in patients with non-GCB DLBCL and high-grade B-cell lymphoma with rearrangements of MYC and BCL2 or BCL6 (or both). Circulating tumor DNA was undetectable in 33% of the patients at the end of ViPOR therapy. With a median follow-up of 40 months, 2-year progression-free survival and overall survival were 34% (95% confidence interval [CI], 21 to 47) and 36% (95% CI, 23 to 49), respectively. CONCLUSIONS: Treatment with ViPOR was associated with durable remissions in patients with specific molecular DLBCL subtypes and was associated with mainly reversible adverse events. (Funded by the Intramural Research Program of the National Cancer Institute and the National Center for Advancing Translational Sciences of the National Institutes of Health and others; ClinicalTrials.gov number, NCT03223610.).


Subject(s)
Adenine , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols , Bridged Bicyclo Compounds, Heterocyclic , Lenalidomide , Lymphoma, Large B-Cell, Diffuse , Piperidines , Prednisone , Sulfonamides , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/mortality , Female , Middle Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Sulfonamides/adverse effects , Sulfonamides/administration & dosage , Sulfonamides/therapeutic use , Aged , Male , Bridged Bicyclo Compounds, Heterocyclic/adverse effects , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Bridged Bicyclo Compounds, Heterocyclic/administration & dosage , Lenalidomide/adverse effects , Lenalidomide/administration & dosage , Lenalidomide/therapeutic use , Piperidines/adverse effects , Piperidines/therapeutic use , Piperidines/administration & dosage , Adult , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/administration & dosage , Prednisone/adverse effects , Prednisone/administration & dosage , Prednisone/therapeutic use , Adenine/analogs & derivatives , Adenine/adverse effects , Adenine/therapeutic use , Adenine/administration & dosage , Aged, 80 and over , Recurrence , Pyrazoles/adverse effects , Pyrazoles/therapeutic use , Pyrazoles/administration & dosage , Pyrimidines/adverse effects , Pyrimidines/therapeutic use , Pyrimidines/administration & dosage , Molecular Targeted Therapy , Progression-Free Survival
17.
AIDS ; 38(9): 1442-1445, 2024 07 15.
Article in English | MEDLINE | ID: mdl-38932750

ABSTRACT

Twenty-eight individuals who experienced proximal renal tubulopathy (PRT, Fanconi syndrome) while receiving tenofovir disoproxil initiated tenofovir alafenamide (TAF) and were followed for 5 years. None developed recurrent PRT or experienced significant changes in estimated glomerular filtration rate (by creatinine or cystatin-C), albuminuria, proteinuria, retinol-binding proteinuria, fractional excretion of phosphate, alkaline phosphatase, or bone mineral density at the lumbar spine. These data suggest that TAF is a well tolerated treatment option for individuals vulnerable to developing PRT.


Subject(s)
Adenine , Alanine , Anti-HIV Agents , Fanconi Syndrome , HIV Infections , Tenofovir , Humans , Tenofovir/adverse effects , Tenofovir/therapeutic use , Tenofovir/analogs & derivatives , Alanine/adverse effects , Alanine/therapeutic use , Male , Anti-HIV Agents/adverse effects , Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , HIV Infections/complications , Adenine/analogs & derivatives , Adenine/adverse effects , Adenine/therapeutic use , Female , Fanconi Syndrome/chemically induced , Adult , Middle Aged
18.
Lancet Gastroenterol Hepatol ; 9(8): 718-733, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38901444

ABSTRACT

BACKGROUND: Phase 3 studies in patients with chronic hepatitis B have shown tenofovir alafenamide to have non-inferior efficacy to tenofovir disoproxil fumarate, with improved renal and bone safety. We conducted this study to evaluate the safety and efficacy of switching to tenofovir alafenamide in participants with chronic hepatitis B and renal or hepatic impairment. METHODS: This open-label, multicentre, phase 2 study was done in eight countries or territories at 30 sites. We recruited adults (≥18 years) with chronic hepatitis B who were virally suppressed on nucleoside or nucleotide analogues and had renal impairment (part A: moderate or severe in cohort 1 [estimated glomerular filtration rate by the Cockcroft-Gault formula (eGFRCG) 15-59 mL/min] or end-stage renal disease [eGFRCG <15 mL/min] on haemodialysis in cohort 2) or hepatic impairment including decompensation (part B: Child-Turcotte-Pugh score 7-12). Participants switched to 25 mg of tenofovir alafenamide given orally once daily for 96 weeks. The primary endpoint was the proportion of participants with viral suppression (HBV DNA <20 IU/mL) at week 24 by missing-equals-failure analysis. Efficacy (full analysis set) and safety (safety analysis set) analyses included all enrolled participants who received at least one dose of the study drug. Week 96 safety was assessed, including renal and bone parameters. This trial is registered at ClinicalTrials.gov, NCT03180619, and is completed. FINDINGS: 124 participants (93 in part A [78 in cohort 1 and 15 in cohort 2] and 31 in part B) were enrolled between Aug 11, 2017, and Oct 17, 2018, and included in the full and safety analysis sets. 106 (85%) participants completed the study. There were 69 (74%) men and 24 (26%) women in part A and 21 (68%) men and ten (32%) women in part B. At week 24, 91 (97·8%, 95% CI 92·4 to 99·7) of 93 individuals in part A (76 [97·4%, 91·0 to 99·7] of 78 in cohort 1 and 15 [100·0%, 78·2 to 100·0] of 15 in cohort 2) and 31 (100·0%, 88·8 to 100·0) in part B had HBV DNA of less than 20 IU/mL. By week 96, the most common adverse event was upper respiratory tract infection, which occurred in 14 (15%) participants in part A and in six (19%) participants in part B. Serious adverse events occurred in 20 (22%) part A participants and in ten (32%) part B participants; none were related to treatment. No treatment-related deaths occurred. At week 96, median change in estimated glomerular filtration rate (Cockcroft-Gault method) was 1·0 mL/min (IQR -2·8 to 4·5) in cohort 1 and -2·4 mL/min (-11·4 to 10·7) in part B. Mean changes in spine and hip bone mineral density were 1·02% (SD 4·44) and 0·20% (3·25) in part A and -0·25% (3·91) and 0·28% (3·25) in part B. INTERPRETATION: Tenofovir alafenamide might offer continued antiviral efficacy and a favourable safety profile for patients with renal or hepatic impairment and chronic hepatitis B switching from tenofovir disoproxil fumarate or other antivirals. FUNDING: Gilead Sciences.


Subject(s)
Adenine , Alanine , Antiviral Agents , Hepatitis B, Chronic , Tenofovir , Humans , Male , Female , Tenofovir/therapeutic use , Tenofovir/adverse effects , Tenofovir/analogs & derivatives , Hepatitis B, Chronic/drug therapy , Middle Aged , Alanine/therapeutic use , Alanine/adverse effects , Antiviral Agents/therapeutic use , Antiviral Agents/adverse effects , Adult , Adenine/analogs & derivatives , Adenine/therapeutic use , Adenine/adverse effects , Drug Substitution , Aged , Treatment Outcome , Glomerular Filtration Rate/drug effects
20.
J Nat Prod ; 87(6): 1618-1627, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38887968

ABSTRACT

Rogersonins C-F (1-4), four unprecedented adenine-polyketide hybrids featuring a rare 9H-imidazo[2,1-i]purine (1,N6-ethenoadenine) moiety, were isolated from an Ophiocordyceps-associated fungus, Clonostachys rogersoniana. Their structures were elucidated primarily by NMR experiments. The absolute configurations of 1-4 were assigned by a combination of the modified Mosher method, chemical degradation, electronic circular dichroism (ECD) calculations, and X-ray crystallography using Cu Kα radiation. Compound 3 downregulated the expression of PD-L1 protein in MDA-MB-231 and A549 cells, but did not show detectable effect on mRNA transcription of the PD-L1-encoding gene CD274.


Subject(s)
Adenine , Hypocreales , Humans , Molecular Structure , Adenine/chemistry , Hypocreales/chemistry , Purines/chemistry , Crystallography, X-Ray , Cell Line, Tumor , Imidazoles/chemistry
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