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Clinical Cancer Research : An Official... Feb 2022There is increasing recognition that progress in immuno-oncology could be accelerated by evaluating immune-based therapies in dogs with spontaneous cancers. Osteosarcoma...
Losartan Blocks Osteosarcoma-Elicited Monocyte Recruitment, and Combined With the Kinase Inhibitor Toceranib, Exerts Significant Clinical Benefit in Canine Metastatic Osteosarcoma.
PURPOSE
There is increasing recognition that progress in immuno-oncology could be accelerated by evaluating immune-based therapies in dogs with spontaneous cancers. Osteosarcoma (OS) is one tumor for which limited clinical benefit has been observed with the use of immune checkpoint inhibitors. We previously reported the angiotensin receptor blocker losartan suppressed metastasis in preclinical mouse models through blockade of CCL2-CCR2 monocyte recruitment. Here we leverage dogs with spontaneous OS to determine losartan's safety and pharmacokinetics associated with monocyte pharmacodynamic endpoints, and assess its antitumor activity, in combination with the kinase inhibitor toceranib.
PATIENTS AND METHODS
CCL2 expression, monocyte infiltration, and monocyte recruitment by human and canine OS tumors and cell lines were assessed by gene expression, ELISA, and transwell migration assays. Safety and efficacy of losartan-toceranib therapy were evaluated in 28 dogs with lung metastatic OS. Losartan PK and monocyte PD responses were assessed in three dose cohorts of dogs by chemotaxis, plasma CCL2, and multiplex cytokine assays, and RNA-seq of losartan-treated human peripheral blood mononuclear cells.
RESULTS
Human and canine OS cells secrete CCL2 and elicit monocyte migration, which is inhibited by losartan. Losartan PK/PD studies in dogs revealed that a 10-fold-higher dose than typical antihypertensive dosing was required for blockade of monocyte migration. Treatment with high-dose losartan and toceranib was well-tolerated and induced a clinical benefit rate of 50% in dogs with lung metastases.
CONCLUSIONS
Losartan inhibits the CCL2-CCR2 axis, and in combination with toceranib, exerts significant biological activity in dogs with metastatic osteosarcoma, supporting evaluation of this drug combination in patients with pediatric osteosarcoma. See related commentary by Weiss et al., p. 571.
Topics: Animals; Bone Neoplasms; Dog Diseases; Dogs; Humans; Leukocytes, Mononuclear; Losartan; Mice; Monocytes; Osteosarcoma
PubMed: 34580111
DOI: 10.1158/1078-0432.CCR-21-2105 -
Translational Vision Science &... Jul 2022To evaluate the efficacy of losartan and prednisolone acetate in inhibiting corneal scarring fibrosis after alkali burn injury in rabbits.
PURPOSE
To evaluate the efficacy of losartan and prednisolone acetate in inhibiting corneal scarring fibrosis after alkali burn injury in rabbits.
METHODS
Sixteen New Zealand White rabbits were included. Alkali injuries were produced using 1N sodium hydroxide on a 5-mm diameter Whatman #1 filter paper for 1 minute. Four corneas in each group were treated six times per day for 1 month with 50 µL of (1) 0.8 mg/mL losartan in balanced salt solution (BSS), (2) 1% prednisolone acetate, (3) combined 0.8 mg/mL losartan and 1% prednisolone acetate, or (4) BSS. Area of opacity and total opacity were analyzed in standardized slit-lamp photos with ImageJ. Corneas in both groups were cryofixed in Optimal cutting temperature (OCT) compound at 1 month after surgery, and immunohistochemistry was performed for alpha-smooth muscle actin (α-SMA) and keratocan or transforming growth factor β1 and collagen type IV with ImageJ quantitation.
RESULTS
Combined topical losartan and prednisolone acetate significantly decreased slit-lamp opacity area and intensity, as well as decreased stromal myofibroblast α-SMA area and intensity of staining per section and confined myofibroblasts to only the posterior stroma with repopulation of the anterior and mid-stroma with keratocan-positive keratocytes after 1 month of treatment. Corneal fibroblasts produced collagen type IV not associated with basement membranes, and this production was decreased by topical losartan.
CONCLUSIONS
Combined topical losartan and prednisolone acetate decreased myofibroblast-associated fibrosis after corneal alkali burns that produced full-thickness injury, including corneal endothelial damage. Increased dosages and duration of treatment may further decrease scarring fibrosis.
TRANSLATIONAL RELEVANCE
Topical losartan and prednisolone acetate decrease myofibroblast-mediated scarring fibrosis after corneal injury.
Topics: Adrenal Cortex Hormones; Alkalies; Animals; Burns, Chemical; Cicatrix; Collagen Type IV; Corneal Diseases; Corneal Injuries; Fibrosis; Losartan; Myofibroblasts; Rabbits
PubMed: 35819289
DOI: 10.1167/tvst.11.7.9 -
Cells Nov 2021Hypertensive nephrosclerosis is the second most common cause of end-stage renal disease after diabetes. For years, hypertensive kidney disease has been focused on the... (Review)
Review
Hypertensive nephrosclerosis is the second most common cause of end-stage renal disease after diabetes. For years, hypertensive kidney disease has been focused on the afferent arterioles and glomeruli damage and the involvement of the renin angiotensin system (RAS). Nonetheless, in recent years, novel evidence has demonstrated that persistent high blood pressure injures tubular cells, leading to epithelial-mesenchymal transition (EMT) and tubulointerstitial fibrosis. Injury primarily determined at the glomerular level by hypertension causes changes in post-glomerular peritubular capillaries that in turn induce endothelial damage and hypoxia. Microvasculature dysfunction, by inducing hypoxic environment, triggers inflammation, EMT with epithelial cells dedifferentiation and fibrosis. Hypertensive kidney disease also includes podocyte effacement and loss, leading to disruption of the filtration barrier. This review highlights the molecular mechanisms and histologic aspects involved in the pathophysiology of hypertensive kidney disease incorporating knowledge about EMT and tubulointerstitial fibrosis. The role of the Hsp70 chaperone on the angiotensin II-induced EMT after angiotensin II type 1 receptor (ATR) blockage, as a possible molecular target for therapeutic strategy against hypertensive renal damage is discussed.
Topics: Animals; Epithelial-Mesenchymal Transition; HSP70 Heat-Shock Proteins; Humans; Hypertension, Renal; Kidney; Losartan; Nephritis; Protective Agents
PubMed: 34831368
DOI: 10.3390/cells10113146 -
Biomedicine & Pharmacotherapy =... May 2022The genesis and development of renal fibrosis involve a variety of pathways closely related to inflammation, cytokines, oxidative stress and metabolic abnormalities....
The genesis and development of renal fibrosis involve a variety of pathways closely related to inflammation, cytokines, oxidative stress and metabolic abnormalities. Renal fibrosis is the result of a complex combination of a variety of lesions. Epithelial-mesenchymal transdifferentiation (EMT) of renal tubular epithelial cells is considered the key to renal fibrosis. Losartan is a typical Angiotensin II (ANG II) receptor antagonist and relaxes blood vessels. In this study, we investigated the effects of losartan on Unilateral Ureteral Obstruction (UUO) model mice by studying the changes in the TGF-β/Smad and metabolomics. Male C57BL/6 J mice were intervened with the UUO model and given losartan (10, 20, 30 mg/kg/d) for 28 consecutive days. The results showed that losartan could reduce UUO-induced abnormal serum metabolic spectrum and renal function. It could also improve renal tubular-interstitial injury and fibrosis by reducing tubulointerstitial dilation and collagen deposition. In addition, losartan promoted the expression of Smurf2 and Smurf1, i.e., Smad7 and E3 ubiquitin-linked enzymes, in the nucleus to degrade the type I receptor of TGF-β1 (TβR-I) and P-Smad2/3 to inhibit renal tubular epithelial cells EMT. In summary, these findings indicated that losartan could regulate the TGF-β/Smad and metabolic pathway in UUO model mice through ubiquitination to reduce renal fibrosis.
Topics: Animals; Fibrosis; Kidney; Kidney Diseases; Losartan; Male; Metabolic Networks and Pathways; Mice; Mice, Inbred C57BL; Signal Transduction; Transforming Growth Factor beta; Transforming Growth Factor beta1; Ureteral Obstruction
PubMed: 36068784
DOI: 10.1016/j.biopha.2022.112931 -
Science Translational Medicine Jul 2021Hearing loss is one of the most common symptoms of neurofibromatosis type 2 (NF2) caused by vestibular schwannomas (VSs). Fibrosis in the VS tumor microenvironment (TME)...
Hearing loss is one of the most common symptoms of neurofibromatosis type 2 (NF2) caused by vestibular schwannomas (VSs). Fibrosis in the VS tumor microenvironment (TME) is associated with hearing loss in patients with NF2. We hypothesized that reducing the fibrosis using losartan, an FDA-approved antihypertensive drug that blocks fibrotic and inflammatory signaling, could improve hearing. Using NF2 mouse models, we found that losartan treatment normalized the TME by (i) reducing neuroinflammatory IL-6/STAT3 signaling and preventing hearing loss, (ii) normalizing tumor vasculature and alleviating neuro-edema, and (iii) increasing oxygen delivery and enhancing efficacy of radiation therapy. In preparation to translate these exciting findings into the clinic, we used patient samples and data and demonstrated that IL-6/STAT3 signaling inversely associated with hearing function, that elevated production of tumor-derived IL-6 was associated with reduced viability of cochlear sensory cells and neurons in ex vivo organotypic cochlear cultures, and that patients receiving angiotensin receptor blockers have no progression in VS-induced hearing loss compared with patients on other or no antihypertensives based on a retrospective analysis of patients with VS and hypertension. Our study provides the rationale and critical data for a prospective clinical trial of losartan in patients with VS.
Topics: Animals; Hearing Loss; Humans; Losartan; Mice; Neurilemmoma; Neurofibromatosis 2; Prospective Studies; Retrospective Studies; Rodentia; Treatment Outcome; Tumor Microenvironment
PubMed: 34261799
DOI: 10.1126/scitranslmed.abd4816 -
International Journal of Molecular... Oct 2022In this study, we developed a sustained-release transdermal delivery system containing losartan potassium (LP) and verapamil hydrochloride (VPH). LP and VPH have low...
In this study, we developed a sustained-release transdermal delivery system containing losartan potassium (LP) and verapamil hydrochloride (VPH). LP and VPH have low bioavailability and long half-life. Therefore, the development of an optimum administration mode is necessary to overcome these drawbacks and enhance the antihypertensive effect. A transdermal diffusion meter was used to determine the optimal formulation of LP-VPH transdermal drug delivery systems (TDDS). Based on in vitro results, a sustained-release patch was prepared. Physical characteristics, including quality, stickiness, and appearance, were evaluated in vitro, while pharmacokinetics and skin irritation were evaluated in vivo. The results showed that 8.3% polyvinyl alcohol, 74.7% polyvinylpyrrolidone K30, 12% oleic acid-azone, and 5% polyacrylic acid resin II provided an optimized TDDS product for effective administration of LP and VPH. Furthermore, in vitro and in vivo release tests showed that the system continuously released LP and VPH for 24 h. The pharmacokinetic results indicated that although the maximum concentration was lower, both the area under the curve from 0-time and the mean residence time of the prepared patch were significantly higher than those of the oral preparations. Furthermore, the prepared LP-VPH transdermal patch showed good stability and no skin irritation. The developed LP-VPH TDDS showed a sustained-release effect and good characteristics and pharmacokinetics; therefore, it is an ideal formulation.
Topics: Losartan; Delayed-Action Preparations; Verapamil; Skin Absorption; Administration, Cutaneous; Drug Delivery Systems
PubMed: 36361834
DOI: 10.3390/ijms232113051 -
Molecules (Basel, Switzerland) Apr 2022Losartan potassium salt (LSR) is a well-known antihypertensive drug with proven beneficial effects on human health. Its formulation with the non-toxic...
Losartan potassium salt (LSR) is a well-known antihypertensive drug with proven beneficial effects on human health. Its formulation with the non-toxic 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) could improve its pharmacological profile. Thus, its molecular interactions are studied using a combination of Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance (NMR) and Molecular Dynamics (MD). First, its complexation is shown through Differential Scanning Calorimetry as lyophilization provided distinct thermal properties in comparison to the mixture. The complexation is further proved by utilizing the chemical shift changes in the complexation and T1 values. Furthermore, the reversible favorable complexation was shown by MD calculations. Such physical chemical properties provide evidence that this formulation must be further explored through biological experiments.
Topics: 2-Hydroxypropyl-beta-cyclodextrin; Antihypertensive Agents; Calorimetry, Differential Scanning; Freeze Drying; Humans; Hypromellose Derivatives; Losartan; Solubility
PubMed: 35458617
DOI: 10.3390/molecules27082421 -
The Lancet. Neurology Nov 2021Drugs modifying angiotensin II signalling could reduce Alzheimer's disease pathology, thus decreasing the rate of disease progression. We investigated whether the... (Randomized Controlled Trial)
Randomized Controlled Trial
Safety and efficacy of losartan for the reduction of brain atrophy in clinically diagnosed Alzheimer's disease (the RADAR trial): a double-blind, randomised, placebo-controlled, phase 2 trial.
BACKGROUND
Drugs modifying angiotensin II signalling could reduce Alzheimer's disease pathology, thus decreasing the rate of disease progression. We investigated whether the angiotensin II receptor antagonist losartan, compared with placebo, could reduce brain volume loss, as a measure of disease progression, in clinically diagnosed mild-to-moderate Alzheimer's disease.
METHODS
In this double-blind, multicentre, randomised controlled trial, eligible patients aged 55 years or older, previously untreated with angiotensin II drugs and diagnosed (National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association criteria) with mild-to-moderate Alzheimer's disease, and who had capacity to consent, were recruited from 23 UK National Health Service hospital trusts. After undergoing a 4-week, open-label phase of active treatment then washout, participants were randomly assigned (1:1) oral over-encapsulated preparations of either 100 mg losartan (after an initial two-dose titration stage) or matched placebo daily for 12 months. Randomisation, minimised by age and baseline medial temporal lobe atrophy score, was undertaken online or via pin-access service by telephone. Participants, their study companions, and study personnel were masked to group assignment. The primary outcome, analysed by the intention-to-treat principle (ie, participants analysed in the group to which they were randomised, without imputation for missing data), was change in whole brain volume between baseline and 12 months, measured using volumetric MRI and determined by boundary shift interval (BSI) analysis. The trial is registered with the International Standard Randomised Controlled Trial Register (ISRCTN93682878) and the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT 2012-003641-15), and is completed.
FINDINGS
Between July 22, 2014, and May 17, 2018, 261 participants entered the open-label phase. 211 were randomly assigned losartan (n=105) or placebo (n=106). Of 197 (93%) participants who completed the study, 171 (81%) had complete primary outcome data. The mean brain volume (BSI) reduction was 19·1 mL (SD 10·3) in the losartan group and 20·0 mL (10·8) in the placebo group. The difference in total volume reduction between groups was -2·29 mL (95% CI -6·46 to 0·89; p=0·14). The number of adverse events was low (22 in the losartan group and 20 in the placebo group) with no differences between treatment groups. There was one treatment-related death per treatment group.
INTERPRETATION
12 months of treatment with losartan was well tolerated but was not effective in reducing the rate of brain atrophy in individuals with clinically diagnosed mild-to-moderate Alzheimer's disease. Further research is needed to assess the potential therapeutic benefit from earlier treatment in patients with milder cognitive impairment or from longer treatment periods.
FUNDING
Efficacy and Mechanism Evaluation Programme (UK Medical Research Council and National Institute for Health Research).
Topics: Alzheimer Disease; Atrophy; Brain; Double-Blind Method; Humans; Losartan; Middle Aged; State Medicine; Treatment Outcome
PubMed: 34687634
DOI: 10.1016/S1474-4422(21)00263-5 -
Journal of Cardiology Jul 2023Serum uric acid (SUA) is activated in catabolic, hypoxic, and inflammatory conditions characteristic of heart failure (HF) and is a source of reactive oxygen species.... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Serum uric acid (SUA) is activated in catabolic, hypoxic, and inflammatory conditions characteristic of heart failure (HF) and is a source of reactive oxygen species. Losartan is unique among other angiotensin receptor blockers in reducing SUA.
OBJECTIVES
To study the patient characteristics and outcome associations by SUA levels, as well as the effect of high- vs. low-dose losartan on SUA levels in HF.
METHODS
HEAAL was a double-blind trial, comparing the effect of two doses of losartan 150 (high dose) vs. 50 (low dose) mg/day among 3834 patients with symptomatic HF, a left ventricular ejection fraction≤40 %, and known intolerance to angiotensin-converting enzyme inhibitors. In the present study, we studied the associations of SUA with outcomes and the effect of high- vs. low-dose losartan on SUA levels, incident hyperuricemia, and gout.
RESULTS
Patients with higher SUA had more comorbidities, worse renal function, were more symptomatic, used diuretics more frequently, and were 1.5- to 2-fold more likely to experience HF hospitalizations and cardiovascular death. The benefit of high-dose losartan to improve HF outcomes was not influenced by baseline SUA levels (interaction p > 0.1). Compared with low-dose, high-dose losartan reduced SUA by -0.27 (-0.34 to -0.21) mg/dL, p < 0.001. The incidence of hyperuricemia was reduced with high-dose losartan, but the incidence of gout was not.
CONCLUSIONS
In HEAAL, hyperuricemia was associated with worse outcomes. High-dose losartan reduced SUA and hyperuricemia more than low-dose and the cardiovascular benefits of high-dose losartan were not modified by SUA levels.
Topics: Humans; Losartan; Uric Acid; Hyperuricemia; Stroke Volume; Ventricular Function, Left; Heart Failure
PubMed: 37030532
DOI: 10.1016/j.jjcc.2023.04.005 -
Journal of Clinical Hypertension... Oct 2023Serum urate is a risk factor for hypertension and gout. The DASH diet and losartan independently lower blood pressure (BP); however, their effects on serum urate are... (Randomized Controlled Trial)
Randomized Controlled Trial
Serum urate is a risk factor for hypertension and gout. The DASH diet and losartan independently lower blood pressure (BP); however, their effects on serum urate are understudied. We performed a post-hoc analysis of the DASH-losartan trial, which randomized participants with hypertension in parallel fashion to the DASH diet or a standard American diet (control) and in crossover fashion to 4-week losartan or placebo. Serum urate was measured at baseline and after each 4-week period. Diets were designed to maintain weight constant. We examined the effects of DASH (vs control) and/or losartan (vs placebo) on serum urate, overall and among those with baseline serum urate ≥6 mg/dL, using generalized estimating equations. Of 55 participants (mean age 52 years, 58% women, 64% Black), mean (±SD) baseline ambulatory SBP/DBP was 146±12/91±9 and mean (±SD) serum urate was 5.2±1.2 mg/dL. The DASH diet did not significantly reduce urate levels overall (mean difference -0.05 mg/dL; 95%CI: -0.39, 0.28), but did decrease levels among participants with baseline hyperuricemia (-0.33 mg/dL; 95%CI: -0.87, 0.21; P-interaction=0.007 across hyperuricemia groups). Losartan significantly decreased serum urate (-0.23 mg/dL; 95%CI: -0.40, -0.05) with greater effects on serum urate among adults <60 years old versus adults ≥60 years old (-0.33 mg/dL vs 0.16 mg/dL, P interaction = 0.003). In summary, the DASH diet significantly decreased serum urate among participants with higher urate at baseline, while losartan significantly reduced serum urate, especially among younger adults. Future research should examine the effects of these interventions in patients with hyperuricemia or gout.
Topics: Humans; Adult; Female; Middle Aged; Male; Hypertension; Losartan; Uric Acid; Hyperuricemia; Dietary Approaches To Stop Hypertension; Gout
PubMed: 37695134
DOI: 10.1111/jch.14721