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Journal of Ocular Pharmacology and... Apr 2023Losartan is an angiotensin II receptor blocker (ARB) that impedes transforming growth factor (TGF) beta signaling by inhibiting activation of signal transduction... (Review)
Review
Losartan is an angiotensin II receptor blocker (ARB) that impedes transforming growth factor (TGF) beta signaling by inhibiting activation of signal transduction molecule extracellular signal-regulated kinase (ERK). Studies supported the efficacy of topical losartan in decreasing scarring fibrosis after rabbit Descemetorhexis, alkali burn, and photorefractive keratectomy injuries, and in case reports of humans with scarring fibrosis after surgical complications. Clinical studies are needed to explore the efficacy and safety of topical losartan in the prevention and treatment of corneal scarring fibrosis, and other eye diseases and disorders where TGF beta has a role in pathophysiology. These include scarring fibrosis associated with corneal trauma, chemical burns, infections, surgical complications, and persistent epithelial defects, as well as conjunctival fibrotic diseases, such as ocular cicatricial pemphigoid and Stevens-Johnson syndrome. Research is also needed to explore the efficacy and safety of topical losartan for hypothesized treatment of transforming growth factor beta-induced ()-related corneal dystrophies (Reis-Bu¨cklers corneal dystrophy, lattice corneal dystrophy type 1, and granular corneal dystrophies type 1 and type 2) where deposited mutant protein expression is modulated by TGF beta. Investigations could also explore the efficacy and safety of topical losartan treatments to reduce conjunctival bleb scarring and shunt encapsulation following glaucoma surgical procedures. Losartan and sustained release drug delivery devices could be efficacious in treating intraocular fibrotic diseases. Dosing suggestions and precautions that should be considered in trials of losartan are detailed. Losartan, as an adjuvant to current treatments, has the potential to augment pharmacological therapeutics for many ocular diseases and disorders where TGF beta plays a central role in pathophysiology.
Topics: Animals; Humans; Rabbits; Losartan; Cicatrix; Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Corneal Dystrophies, Hereditary; Eye Diseases; Fibrosis; Transforming Growth Factor beta; Corneal Injuries
PubMed: 36877777
DOI: 10.1089/jop.2022.0174 -
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 -
American Journal of Cardiovascular... Jul 2023Few data are available regarding the efficacy and safety of a single-pill combination (SPC) consisting of four medications in patients with concomitant hypertension and... (Randomized Controlled Trial)
Randomized Controlled Trial
A Randomized, Multicenter, Double-blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of a Quadruple Combination of Amlodipine, Losartan, Rosuvastatin, and Ezetimibe in Patients with Concomitant Essential Hypertension and Dyslipidemia.
BACKGROUND
Few data are available regarding the efficacy and safety of a single-pill combination (SPC) consisting of four medications in patients with concomitant hypertension and dyslipidemia.
OBJECTIVE
We aimed to determine the efficacy and tolerability of a fixed-dose SPC consisting of 5 mg amlodipine, 100 mg losartan, 20 mg rosuvastatin, and 10 mg ezetimibe (A/L/R/E) in patients with concomitant hypertension and dyslipidemia.
METHODS
This was a 14-week, randomized, multicenter, double-blind, placebo-controlled, phase III clinical trial. In total, 145 patients were randomized to receive A/L/R/E, A/L, or L/R/E. The primary endpoints were the average change in the low-density lipoprotein cholesterol (LDL-C) level in the A/L/R/E and A/L groups and the sitting systolic blood pressure (sitSBP) in the A/L/R/E and L/R/E groups. The numbers of patients with adverse drug reactions (ADRs) were compared as safety variables.
RESULTS
The average percentage change in the LDL-C level as the least squares mean (LSM) from the baseline LDL-C level at the end of the 8-week treatment was - 59.0% in the A/L/R/E group and 0.2% in the A/L group (LSM difference - 59.2, 95% confidence interval [CI] - 68.1 to - 50.4; p < 0.0001). The average change in the sitSBP as the LSM was - 15.8 mmHg in the A/L/R/E group and -4.7 mmHg in the L/R/E group (LSM difference - 11.1, 95% CI - 16.8 to - 5.4; p = 0.0002). No ADRs occurred in the A/L/R/E group.
CONCLUSIONS
A/L/R/E as an SPC could be an effective treatment for patients with hypertension and dyslipidemia without significant safety issues.
CLINICAL TRIALS REGISTRATION
NCT04074551 (registered 30 August 2019).
Topics: Humans; Losartan; Rosuvastatin Calcium; Antihypertensive Agents; Ezetimibe; Cholesterol, LDL; Blood Pressure; Amlodipine; Hypertension; Essential Hypertension; Dyslipidemias; Double-Blind Method; Treatment Outcome
PubMed: 37395974
DOI: 10.1007/s40256-023-00590-9 -
Clinical Cardiology Aug 2023This study aimed to evaluate the efficacy of single-pill combination (SPC) antihypertensive drugs in patients with uncontrolled essential hypertension. Through Searching... (Meta-Analysis)
Meta-Analysis Review
This study aimed to evaluate the efficacy of single-pill combination (SPC) antihypertensive drugs in patients with uncontrolled essential hypertension. Through Searching Pubmed, EMBASE, the Cochrane Library, and Web of Science collected only randomized controlled trials on the efficacy of single-pill combination antihypertensive drugs in people with uncontrolled essential hypertension. The search period is from the establishment of the database to July 2022. The methodological quality of the included studies was assessed using the Cochrane Risk of Bias Assessment, and statistical analyses were performed using Review Manage 5.3 and Stata 15.1 software. This review ultimately included 32 references involving 16 273 patients with uncontrolled essential hypertension. The results of the network meta-analysis showed that a total of 11 single-pill combination antihypertensive drugs were included, namely: Amlodipine/valsartan, Telmisartan/amlodipine, Losartan/HCTZ, Candesartan/HCTZ, Amlodipine/benazepril, Telmisartan/HCTZ, Valsartan/HCTZ, Irbesartan/amlodipine, Amlodipine/losartan, Irbesartan/HCTZ, and Perindopril/amlodipine. According to SUCRA, Irbesartan/amlodipine may rank first in reducing systolic blood pressure (SUCRA: 92.2%); Amlodipine/losartan may rank first in reducing diastolic blood pressure (SUCRA: 95.1%); Telmisartan/amlodipine may rank first in blood pressure control rates (SUCRA: 83.5%); Amlodipine/losartan probably ranks first in diastolic response rate (SUCRA: 84.5%). Based on Ranking Plot of the Network, we can conclude that single-pill combination antihypertensive drugs are superior to monotherapy, and ARB/CCB combination has better advantages than other SPC in terms of systolic blood pressure, diastolic blood pressure, blood pressure control rate, and diastolic response rate. However, due to the small number of some drug studies, the lack of relevant studies has led to not being included in this study, which may impact the results, and readers should interpret the results with caution.
Topics: Humans; Antihypertensive Agents; Losartan; Hypertension; Telmisartan; Irbesartan; Angiotensin Receptor Antagonists; Network Meta-Analysis; Hydrochlorothiazide; Valine; Drug Therapy, Combination; Angiotensin-Converting Enzyme Inhibitors; Amlodipine; Valsartan; Tetrazoles; Blood Pressure; Essential Hypertension
PubMed: 37432701
DOI: 10.1002/clc.24082 -
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 -
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 -
Pharmacological Research Dec 2021Angiotensin II (AngII) is implicated in neuroinflammation, blood-brain barrier (BBB) disruption, and autonomic dysfunction in hypertension. We have previously shown that...
Angiotensin II (AngII) is implicated in neuroinflammation, blood-brain barrier (BBB) disruption, and autonomic dysfunction in hypertension. We have previously shown that exogenous AngII stimulates Toll-like receptor 4 (TLR4) via AngII type 1 receptor (AT1R), inducing activation of hypothalamic microglia ex vivo, and that AngII-AT1R signaling is necessary for the loss of BBB integrity in spontaneously hypertensive rats (SHRs). Herein, we hypothesized that microglial TLR4 and AT1R signaling interactions represent a crucial mechanistic link between AngII-mediated neuroinflammation and BBB disruption, thereby contributing to sympathoexcitation in SHRs. Male SHRs were treated with TAK-242 (TLR4 inhibitor; 2 weeks), Losartan (AT1R inhibitor; 4 weeks), or vehicle, and age-matched to control Wistar Kyoto rats (WKYs). TLR4 and AT1R inhibitions normalized increased TLR4, interleukin-6, and tumor necrosis factor-α protein densities in SHR cardioregulatory nuclei (hypothalamic paraventricular nucleus [PVN], rostral ventrolateral medulla [RVLM], and nucleus tractus solitarius [NTS]), and abolished enhanced microglial activation. PVN, RVLM, and NTS BBB permeability analyses revealed complete restoration after TAK-242 treatment, whereas SHRs presented with elevated dye leakage. Mean arterial pressure was normalized in Losartan-treated SHRs, and attenuated with TLR4 inhibition. In conscious assessments, TLR4 blockade rescued SHR baroreflex sensitivity to vasoactive drugs, and reduced the SHR pressor response to ganglionic blockade to normal levels. These data suggest that TLR4 activation plays a substantial role in mediating a feed-forward pro-hypertensive cycle involving BBB disruption, neuroinflammation, and autonomic dysfunction, and that TLR4-specific therapeutic interventions may represent viable alternatives in the treatment of hypertension.
Topics: Angiotensin II Type 1 Receptor Blockers; Animals; Arterial Pressure; Baroreflex; Brain; Heart Rate; Hypertension; Losartan; Male; Microglia; Neuroinflammatory Diseases; Permeability; Rats, Inbred SHR; Rats, Inbred WKY; Receptor, Angiotensin, Type 1; Sulfonamides; Toll-Like Receptor 4; Rats
PubMed: 34610452
DOI: 10.1016/j.phrs.2021.105877