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Pharmacological Reviews Apr 2020The solute carrier family 16 (SLC16) is comprised of 14 members of the monocarboxylate transporter (MCT) family that play an essential role in the transport of important... (Review)
Review
The solute carrier family 16 (SLC16) is comprised of 14 members of the monocarboxylate transporter (MCT) family that play an essential role in the transport of important cell nutrients and for cellular metabolism and pH regulation. MCTs 1-4 have been extensively studied and are involved in the proton-dependent transport of L-lactate, pyruvate, short-chain fatty acids, and monocarboxylate drugs in a wide variety of tissues. MCTs 1 and 4 are overexpressed in a number of cancers, and current investigations have focused on transporter inhibition as a novel therapeutic strategy in cancers. MCT1 has also been used in strategies aimed at enhancing drug absorption due to its high expression in the intestine. Other MCT isoforms are less well characterized, but ongoing studies indicate that MCT6 transports xenobiotics such as bumetanide, nateglinide, and probenecid, whereas MCT7 has been characterized as a transporter of ketone bodies. MCT8 and MCT10 transport thyroid hormones, and recently, MCT9 has been characterized as a carnitine efflux transporter and MCT12 as a creatine transporter. Expressed at the blood brain barrier, MCT8 mutations have been associated with an X-linked intellectual disability, known as Allan-Herndon-Dudley syndrome. Many MCT isoforms are associated with hormone, lipid, and glucose homeostasis, and recent research has focused on their potential roles in disease, with MCTs representing promising novel therapeutic targets. This review will provide a summary of the current literature focusing on the characterization, function, and regulation of the MCT family isoforms and on their roles in drug disposition and in health and disease. SIGNIFICANCE STATEMENT: The 14-member solute carrier family 16 of monocarboxylate transporters (MCTs) plays a fundamental role in maintaining intracellular concentrations of a broad range of important endogenous molecules in health and disease. MCTs 1, 2, and 4 (L-lactate transporters) are overexpressed in cancers and represent a novel therapeutic target in cancer. Recent studies have highlighted the importance of MCTs in glucose, lipid, and hormone homeostasis, including MCT8 in thyroid hormone brain uptake, MCT12 in carnitine transport, and MCT11 in type 2 diabetes.
Topics: Animals; Humans; Metabolic Diseases; Monocarboxylic Acid Transporters; Structure-Activity Relationship; Tissue Distribution; Transcription, Genetic
PubMed: 32144120
DOI: 10.1124/pr.119.018762 -
Nature Communications Mar 2022Pannexin-1 (Panx1) channels have been shown to regulate leukocyte trafficking and tissue inflammation but the mechanism of Panx1 in chronic vascular diseases like...
Pannexin-1 (Panx1) channels have been shown to regulate leukocyte trafficking and tissue inflammation but the mechanism of Panx1 in chronic vascular diseases like abdominal aortic aneurysms (AAA) is unknown. Here we demonstrate that Panx1 on endothelial cells, but not smooth muscle cells, orchestrate a cascade of signaling events to mediate vascular inflammation and remodeling. Mechanistically, Panx1 on endothelial cells acts as a conduit for ATP release that stimulates macrophage activation via P2X7 receptors and mitochondrial DNA release to increase IL-1β and HMGB1 secretion. Secondly, Panx1 signaling regulates smooth muscle cell-dependent intracellular Ca release and vascular remodeling via P2Y2 receptors. Panx1 blockade using probenecid markedly inhibits leukocyte transmigration, aortic inflammation and remodeling to mitigate AAA formation. Panx1 expression is upregulated in human AAAs and retrospective clinical data demonstrated reduced mortality in aortic aneurysm patients treated with Panx1 inhibitors. Collectively, these data identify Panx1 signaling as a contributory mechanism of AAA formation.
Topics: Adenosine Triphosphate; Aortic Aneurysm, Abdominal; Connexins; Endothelial Cells; Humans; Inflammation; Macrophages; Myocytes, Smooth Muscle; Nerve Tissue Proteins; Retrospective Studies
PubMed: 35315432
DOI: 10.1038/s41467-022-29233-4 -
Therapeutic Advances in Musculoskeletal... 2022Gout is characterized by monosodium urate (MSU) crystal deposits in and within joints. These deposits result from persistent hyperuricaemia and most typically lead to... (Review)
Review
Gout is characterized by monosodium urate (MSU) crystal deposits in and within joints. These deposits result from persistent hyperuricaemia and most typically lead to recurrent acute inflammatory episodes (gout flares). Even though some aspects of gout are well characterized, uncertainties remain; this upcoming decade should provide further insights into many of these uncertainties. Synovial fluid analysis allows for the identification of MSU crystals and unequivocal diagnosis. Non-invasive methods for diagnosis are being explored, such as Raman spectroscopy and imaging modalities. Both ultrasound and dual-energy computed tomography (DECT) allow the detection of MSU crystals; this not only provides a mean of diagnosis, but also has furthered gout knowledge defining the presence of a preclinical deposition in asymptomatic hyperuricaemia. Scientific consensus establishes the beginning of gout as the beginning of symptoms (usually the first flare), but the concept is currently under review. For effective long-term gout management, the main goal is to promote crystal dissolution treatment by reducing serum urate below 6 mg/dL (or 5 mg/dL if faster crystal dissolution is required). Current urate-lowering therapies' (ULTs) options are limited, with allopurinol and febuxostat being widely available, and probenecid, benzbromarone, and pegloticase available in some regions. New xanthine oxidase inhibitors and, especially, uricosurics inhibiting urate transporter URAT1 are under development; it is probable that the new decade will see a welcomed increase in the gout therapeutic armamentarium. Cardiovascular and renal comorbidities are common in gout patients. Studies determining whether optimal treatment of gout will positively impact these comorbidities are currently lacking, but will hopefully be forthcoming. Overall, the single change that will most impact gout management is greater uptake of international rheumatology society recommendations. Innovative strategies, such as nurse-led interventions based on these recommendations have recently demonstrated treatment success for people with gout.
PubMed: 35923650
DOI: 10.1177/1759720X221114098 -
Clinical Infectious Diseases : An... Jan 2023Sulopenem is a thiopenem antibiotic being developed for the treatment of multidrug-resistant infections. The availability of both intravenous (IV) and oral formulations... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Sulopenem is a thiopenem antibiotic being developed for the treatment of multidrug-resistant infections. The availability of both intravenous (IV) and oral formulations will facilitate earlier hospital discharge.
METHODS
Hospitalized adults with pyuria, bacteriuria, and signs and symptoms of complicated urinary tract infection (cUTI) were randomized to 5 days of IV sulopenem followed by oral sulopenem etzadroxil/probenecid or 5 days of IV ertapenem followed by oral ciprofloxacin or amoxicillin-clavulanate, depending on uropathogen susceptibility. The primary end point was overall combined clinical and microbiologic response at the test-of-cure visit (day 21).
RESULTS
Of 1392 treated patients, 444 and 440 treated with sulopenem and ertapenem, respectively, had a positive baseline urine culture and were eligible for the primary efficacy analyses. Extended-spectrum β-lactamase-producing organisms were identified in 26.6% of patients and fluoroquinolone-nonsusceptible pathogens in 38.6%. For the primary end point, noninferiority of sulopenem to the comparator regimen was not demonstrated, 67.8% vs 73.9% (difference, -6.1%; 95% confidence interval, -12.0 to -.1%). The difference was driven by a lower rate of asymptomatic bacteriuria in the subgroup of ertapenem-treated patients who stepped down to ciprofloxacin. No substantial difference in overall response was observed at any other time point. Both IV and oral formulations of sulopenem were well-tolerated and compared favorably to the comparator.
CONCLUSIONS
Sulopenem followed by oral sulopenem-etzadroxil/probenecid was not noninferior to ertapenem followed by oral step-down therapy for the treatment of cUTIs, driven by a lower rate of asymptomatic bacteriuria in those who received ciprofloxacin. Both formulations of sulopenem were well-tolerated.
CLINICAL TRIAL REGISTRATION
NCT03357614.
Topics: Adult; Humans; Ertapenem; Bacteriuria; Urinary Tract Infections; Anti-Bacterial Agents; Pyelonephritis; Ciprofloxacin
PubMed: 36068705
DOI: 10.1093/cid/ciac704 -
Autophagy Sep 2023Despite growing evidence that has declared the importance of circRNAs in neurodegenerative diseases, the clinical significance of circRNAs in dopaminergic (DA) neuronal...
Despite growing evidence that has declared the importance of circRNAs in neurodegenerative diseases, the clinical significance of circRNAs in dopaminergic (DA) neuronal degeneration in the pathogenesis of Parkinson disease (PD) remains unclear. Here, we performed rRNA-depleted RNA sequencing and detected more than 10,000 circRNAs in the plasma samples of PD patients. In consideration of ROC and the correlation between Hohen-Yahr stage (H-Y stage) and Unified Parkinson Disease Rating Scale-motor score (UPDRS) of 40 PD patients, was selected for further research. Low expression of was found in PD patients and there was a negative positive correlation between the level and severity of PD motor symptoms, while overexpression of protected DA neurons against neurotoxin-induced PD-like neurodegeneration and . Mechanistically, acted as a sponge to promote the stable expression of target gene , thus enhancing PINK1-PRKN-dependent mitophagy to eliminate damaged mitochondria and maintain mitochondrial homeostasis. Thus, rescued DA neuronal degeneration through the -PINK1 axis-mediated improvement of mitochondrial function. This study reveals that exerts a critical role in participating in PD pathogenesis, and may give us an insight into the novel avenue to develop potential biomarkers and therapeutic targets for PD. AAV: adeno-associated virus; DA: dopaminergic; FISH: fluorescence in situ hybridizations; HPLC: high-performance liquid chromatography; H-Y stage: Hohen-Yahr stage; LDH: lactate dehydrogenase; MMP: mitochondrial membrane potential; MPTP/p: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/probenecid; NC: negative control; PD: Parkinson disease; PINK1: PTEN induced kinase 1; PBS: phosphate-buffered saline; ROS: reactive oxygen species; SNpc: substantia nigra pars compacta; TEM: transmission electron microscopy; UPDRS: Unified Parkinson's Disease Rating Scale-motor score.
Topics: Humans; Parkinson Disease; Mitophagy; RNA, Circular; Autophagy; Dopamine; Dopaminergic Neurons; Protein Kinases; Ubiquitin-Protein Ligases; MicroRNAs
PubMed: 37014258
DOI: 10.1080/15548627.2023.2196889 -
BMC Nephrology Jun 2022Asymptomatic hyperuricemia was found to be associated with increased cardiovascular disease risk but the potential benefits of urate-lowering therapy (ULT) remain... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Asymptomatic hyperuricemia was found to be associated with increased cardiovascular disease risk but the potential benefits of urate-lowering therapy (ULT) remain controversial. We conducted a systematic review and network meta-analysis (NMA) with frequentist model to estimate the efficacy and safety of ULT in asymptomatic hyperuricemia.
METHODS
MEDLINE, Embase, and Scopus were searched without language restrictions. Randomized controlled trials (RCT) of adults with asymptomatic hyperuricemia were eligible if they compared any pair of ULTs (i.e., allopurinol, febuxostat, probenecid, benzbromarone, sulfinpyrazone, rasburicase, lesinurad, and topiroxostat) and placebo or no ULT, and had outcomes of interest, including composite renal events, major adverse cardiovascular events, serum urate levels, estimated glomerular filtration rate (eGFR), systolic blood pressure, and adverse events.
RESULTS
NMA with frequentist approach was applied to estimate relative treatment effects, i.e., risk ratio (RR) and mean difference (MD). A total of 23 RCTs were eligible. NMA identified beneficial effects of ULT on composite renal events and eGFR but not for other outcomes. Allopurinol and febuxostat had significantly lower composite renal events than placebo (RR 0.39, 95% confidence interval [CI] 0.23 to 0.66, and RR 0.68, 95% CI 0.46 to 0.99, respectively). Both treatments also resulted in significantly higher eGFR than placebo (MD 3.69 ml/min/1.73 m, 95% CI 1.31 to 6.08, and MD 2.89 ml/min/1.73 m, 95% CI 0.69 to 5.09, respectively). No evidence of inconsistency was identified.
CONCLUSIONS
Evidence suggests that allopurinol and febuxostat are the ULTs of choice in reducing composite renal events and improving renal function.
TRIAL REGISTRATION
This study was registered with PROSPERO: CRD42019145908. The date of the first registration was 12 November 2019.
Topics: Adult; Allopurinol; Febuxostat; Gout; Gout Suppressants; Humans; Hyperuricemia; Network Meta-Analysis; Randomized Controlled Trials as Topic; Uric Acid
PubMed: 35739495
DOI: 10.1186/s12882-022-02850-3 -
Neurotherapeutics : the Journal of the... Oct 2023N-Acetylcysteine (NAC) has shown promise as a putative neurotherapeutic for traumatic brain injury (TBI). Yet, many such promising compounds have limited ability to... (Review)
Review
N-Acetylcysteine (NAC) has shown promise as a putative neurotherapeutic for traumatic brain injury (TBI). Yet, many such promising compounds have limited ability to cross the blood-brain barrier (BBB), achieve therapeutic concentrations in brain, demonstrate target engagement, among other things, that have hampered successful translation. A pharmacologic strategy for overcoming poor BBB permeability and/or efflux out of the brain of organic acid-based, small molecule therapeutics such as NAC is co-administration with a targeted or nonselective membrane transporter inhibitor. Probenecid is a classic ATP-binding cassette and solute carrier inhibitor that blocks transport of organic acids, including NAC. Accordingly, combination therapy using probenecid as an adjuvant with NAC represents a logical neurotherapeutic strategy for treatment of TBI (and other CNS diseases). We have completed a proof-of-concept pilot study using this drug combination in children with severe TBI-the Pro-NAC Trial (ClinicalTrials.gov NCT01322009). In this review, we will discuss the background and rationale for combination therapy with probenecid and NAC in TBI, providing justification for further clinical investigation.
Topics: Child; Humans; Probenecid; Acetylcysteine; Pilot Projects; Brain Injuries, Traumatic; Brain; Blood-Brain Barrier
PubMed: 37596428
DOI: 10.1007/s13311-023-01422-z