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Aldosterone through the mineralocorticoid receptor MR has detrimental effects on cardiovascular disease. It reduces the bioavailability of nitric oxide and impairs endothelium-dependent vasodilatation. In resistance arteries, aldosterone impairs the sensitivity of vascular smooth muscle cells to nitric oxide by promoting the local secretion of histamine which activates H2 receptors. The present experiments tested in vivo and ex vivo the hypothesis that systemic H2-receptor antagonism reduces arterial blood pressure and improves vasodilatation in angiotensin II-induced chronic hypertension. Hypertension was induced by intravenous infusion of angiotensin II (60 ng kg-1 min-1) in conscious, unrestrained mice infused concomitantly with the H2-receptor antagonist ranitidine (27.8 µg kg-1 min-1) or vehicle for 24 days. Heart rate and arterial blood pressure were recorded by indwelling arterial catheter. Resistance (mesenteric) and conductance (aortae) arteries were harvested for perfusion myography and isometric tension recordings by wire myography, respectively. Plasma was analyzed for aldosterone concentration. ANGII infusion resulted in elevated arterial blood pressure and while in vivo treatment with ranitidine reduced plasma aldosterone concentration, it did not reduce blood pressure. Ranitidine improved ex vivo endothelial function (acetylcholine 10-9 to 10-6 mol L-1) in mesenteric resistance arteries. This was abolished by ex vivo treatment with aldosterone (10-9 mol L-1, 1 h). In aortic segments, in vivo ranitidine treatment impaired relaxation. Activation of histamine H2 receptors promotes aldosterone secretion, does not affect arterial blood pressure, and protects endothelial function in conduit arteries but promotes endothelial dysfunction in resistance arteries during angiotensin II-mediated hypertension. Aldosterone contributes little to angiotensin II-induced hypertension in mice.
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Aldosterona , Hipertensão , Camundongos , Animais , Angiotensina II/farmacologia , Pressão Arterial , Histamina/farmacologia , Antagonistas dos Receptores H2 da Histamina/efeitos adversos , Ranitidina/efeitos adversos , Óxido Nítrico , Pressão Sanguínea , Endotélio Vascular , Artérias MesentéricasRESUMO
Despite the recent advances in our understanding of the role of lipids, metabolites, and related enzymes in mediating kidney injury, there is limited integrated multi-omics data identifying potential metabolic pathways driving impaired kidney function. The limited availability of kidney biopsies from living donors with acute kidney injury has remained a major constraint. Here, we validated the use of deceased transplant donor kidneys as a good model to study acute kidney injury in humans and characterized these kidneys using imaging and multi-omics approaches. We noted consistent changes in kidney injury and inflammatory markers in donors with reduced kidney function. Neighborhood and correlation analyses of imaging mass cytometry data showed that subsets of kidney cells (proximal tubular cells and fibroblasts) are associated with the expression profile of kidney immune cells, potentially linking these cells to kidney inflammation. Integrated transcriptomic and metabolomic analysis of human kidneys showed that kidney arachidonic acid metabolism and seven other metabolic pathways were upregulated following diminished kidney function. To validate the arachidonic acid pathway in impaired kidney function we demonstrated increased levels of cytosolic phospholipase A2 protein and related lipid mediators (prostaglandin E2) in the injured kidneys. Further, inhibition of cytosolic phospholipase A2 reduced injury and inflammation in human kidney proximal tubular epithelial cells in vitro. Thus, our study identified cell types and metabolic pathways that may be critical for controlling inflammation associated with impaired kidney function in humans.
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Injúria Renal Aguda , Fenótipo , Humanos , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/etiologia , Masculino , Pessoa de Meia-Idade , Metabolômica/métodos , Feminino , Transplante de Rim/efeitos adversos , Adulto , Citometria por Imagem/métodos , Rim/patologia , Rim/metabolismo , Fosfolipases A2/metabolismo , Ácido Araquidônico/metabolismo , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Transcriptoma , Dinoprostona/metabolismo , Dinoprostona/análise , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Biópsia , MultiômicaRESUMO
Endothelial dysfunction develops with age and may precede cardiovascular disease. Animal data suggest that T-type calcium channels play an important role in endothelial function, but data from humans are lacking. This study included 15 healthy, sedentary, elderly males for a double blinded, randomized controlled trial. For 8 weeks, they were given 40 mg/day of either efonidipine (L- and T-type calcium channel blocker (CCB)) or nifedipine (L-type CCB). Vascular function was evaluated by graded femoral arterial infusions of acetylcholine (ACh; endothelium-dependent vasodilator) and sodium nitroprusside (endothelium-independent vasodilator) both with and without co-infusion of N-acetylcysteine (NAC; antioxidant). We measured leg blood flow and mean arterial pressure and calculated leg vascular conductance to evaluate the leg vascular responses. Despite no significant change in blood pressure in either group, we observed higher leg blood flow responses (Δ 0.43 ± 0.45 l/min, P = 0.006) and leg vascular conductance (Δ 5.38 ± 5.67 ml/min/mmHg, P = 0.005) to intra-arterial ACh after efonidipine, whereas there was no change in the nifedipine group, and no differences between groups. We found no upregulation of endothelial nitric oxide synthase in vastus lateralis muscle biopsies within or between groups. Smooth muscle cell responsiveness was unaltered by efonidipine or nifedipine. Intravenous co-infusion of NAC did not affect endothelium-dependent vasodilatation in either of the CCB groups. These results suggest that 8 weeks' inhibition of T- and L-type calcium channels augments endothelium-dependent vasodilatory function in healthy elderly males. Further studies are required to elucidate if T-type calcium channel inhibition can counteract endothelial dysfunction.
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Bloqueadores dos Canais de Cálcio , Canais de Cálcio Tipo T , Endotélio Vascular , Nifedipino , Nitrofenóis , Humanos , Masculino , Canais de Cálcio Tipo T/metabolismo , Canais de Cálcio Tipo T/efeitos dos fármacos , Idoso , Bloqueadores dos Canais de Cálcio/farmacologia , Nifedipino/farmacologia , Projetos Piloto , Método Duplo-Cego , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Di-Hidropiridinas/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Vasodilatadores/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Compostos Organofosforados/farmacologia , Acetilcolina/farmacologia , Perna (Membro)/irrigação sanguínea , Nitroprussiato/farmacologia , Pessoa de Meia-IdadeRESUMO
Endothelial cell (EC) injury is a crucial contributor to the progression of diabetic kidney disease (DKD), but the specific EC populations and mechanisms involved remain elusive. Kidney ECs (n = 5464) were collected at three timepoints from diabetic BTBRob/ob mice and non-diabetic littermates. Their heterogeneity, transcriptional changes, and alternative splicing during DKD progression were mapped using SmartSeq2 single-cell RNA sequencing (scRNAseq) and elucidated through pathway, network, and gene ontology enrichment analyses. We identified 13 distinct transcriptional EC phenotypes corresponding to different kidney vessel subtypes, confirmed through in situ hybridization and immunofluorescence. EC subtypes along nephrons displayed extensive zonation related to their functions. Differential gene expression analyses in peritubular and glomerular ECs in DKD underlined the regulation of DKD-relevant pathways including EIF2 signaling, oxidative phosphorylation, and IGF1 signaling. Importantly, this revealed the differential alteration of these pathways between the two EC subtypes and changes during disease progression. Furthermore, glomerular and peritubular ECs also displayed aberrant and dynamic alterations in alternative splicing (AS), which is strongly associated with DNA repair. Strikingly, genes displaying differential transcription or alternative splicing participate in divergent biological processes. Our study reveals the spatiotemporal regulation of gene transcription and AS linked to DKD progression, providing insight into pathomechanisms and clues to novel therapeutic targets for DKD treatment.
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Processamento Alternativo , Nefropatias Diabéticas , Células Endoteliais , Análise de Célula Única , Transcriptoma , Animais , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Camundongos , Análise de Célula Única/métodos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Rim/metabolismo , Rim/patologia , Regulação da Expressão Gênica , Transcrição Gênica , Perfilação da Expressão Gênica/métodos , MasculinoRESUMO
Background: Malignant pleural effusion (MPE) is a common and debilitating condition seen in advanced cancer disease, and life-expectancy is short. Symptoms include pain and severe shortness of breath. Current first-line treatment options include pleural drainage using catheters as well as pleurodesis. However, these treatment modalities are often inefficient and patients need repeated procedures. Pressurized IntraThoracic Aerosol Chemotherapy (PITAC) is a minimally invasive procedure, where antineoplastic agents are nebulized under pressure into the pleural space. Content: We present the preliminary safety, feasibility, and response assessment data for PITAC based on a comprehensive literature review. Summary: Five retrospective studies reported data on 38 PITACs in 21 patients. Data were heterogeneous and incomplete on several important aspects such as procedure, safety, local effect and long-term outcomes. PITAC seems technically feasible with a low risk of complications and may provide some reduction in MPE in selected cases. Outlook: PITAC seems feasible, but prospective phase I and II studies are needed to define safety, indications, and efficacy.
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Genotype by environment interactions (G × E) are frequently observed in herbage production. Understanding the underlying biological mechanisms is important for achieving stable and predictive outputs across production environments. The microbiome is gaining increasing attention as a significant contributing factor to G × E. Here, we focused on the soil microbiome of perennial ryegrass (Lolium perenne L.) grown under field conditions and investigated the soil microbiome variation across different ryegrass varieties to assess whether environmental factors, such as seasonality and nitrogen levels, affect the microbial community. We identified bacteria, archaea, and fungi operational taxonomic units (OTUs) and showed that seasonality and ryegrass variety were the two factors explaining the largest fraction of the soil microbiome diversity. The strong and significant variety-by-treatment-by-seasonal cut interaction for ryegrass dry matter was associated with the number of unique OTUs within each sample. We identified seven OTUs associated with ryegrass dry matter variation. An OTU belonging to the Solirubrobacterales (Thermoleophilales) order was associated with increased plant biomass, supporting the possibility of developing engineered microbiomes for increased plant yield. Our results indicate the importance of incorporating different layers of biological data, such as genomic and soil microbiome data to improve the prediction accuracy of plant phenotypes grown across heterogeneous environments.
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Lolium , Solo , Lolium/genética , Estações do Ano , Nitrogênio , GenótipoRESUMO
Aldosterone has been suggested to be involved in the microvascular complications observed in type 2 diabetes. We aimed to investigate the effect of mineralocorticoid receptor (MR) blockade on endothelial function in individuals with type 2 diabetes compared to healthy controls. We included 12 participants with type 2 diabetes and 14 controls. We measured leg hemodynamics at baseline and during femoral arterial infusion of acetylcholine and sodium nitroprusside before and 8 weeks into treatment with MR blockade (eplerenone). Acetylcholine infusion was repeated with concomitant n-acetylcysteine (antioxidant) infusion. No difference in leg blood flow or vascular conductance was detected before or after the treatment with MR blockade in both groups and there was no difference between groups. Infusion of n-acetylcysteine increased baseline blood flow and vascular conductance, but did not change the vascular response to acetylcholine before or after treatment with MR blockade. Skeletal muscle eNOS content was unaltered by MR blockade and no difference between groups was detected. In conclusion, we found no effect of MR blockade endothelial function in individuals with and without type 2 diabetes. As the individuals with type 2 diabetes did not have vascular dysfunction, these results might not apply to individuals with vascular dysfunction.
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Diabetes Mellitus Tipo 2 , Receptores de Mineralocorticoides , Humanos , Acetilcolina/administração & dosagem , Acetilcolina/farmacologia , Acetilcolina/uso terapêutico , Acetilcisteína , Aldosterona , Diabetes Mellitus Tipo 2/tratamento farmacológicoRESUMO
BACKGROUND: Growth differentiation factor-15 (GDF-15) has been associated with senescence, lower muscle strength, and physical performance in healthy older people. Still, it is not clear whether GDF-15 can be utilized as a biomarker of sarcopenia and frailty in the early stages of hospitalization. We investigated the association of plasma GDF-15 with sarcopenia and frailty in older, acutely admitted medical patients. METHODS: The present study is based on secondary analyses of cross-sectional data from the Copenhagen PROTECT study, a prospective cohort study including 1071 patients ≥65 years of age admitted to the acute medical ward at Copenhagen University Hospital, Bispebjerg, Denmark. Muscle strength was assessed using handgrip strength, and lean mass was assessed using direct segmental multifrequency bioelectrical impedance analyses and used to clarify the potential presence of sarcopenia defined according to guidelines from the European Working Group on Sarcopenia in Older People. Frailty was evaluated using the Clinical Frailty Scale. Plasma GDF-15 was measured using electrochemiluminescence assays from Meso Scale Discovery (MSD, Rockville, MD, USA). RESULTS: We included 1036 patients with completed blood samples (mean age 78.9 ± 7.8 years, 53% female). The median concentration of GDF-15 was 2669.3 pg/mL. Systemic GDF-15 was significantly higher in patients with either sarcopenia (P < 0.01) or frailty (P < 0.001) compared with patients without the conditions. Optimum cut-off points of GDF-15 relating to sarcopenia and frailty were 1541 and 2166 pg/mL, respectively. CONCLUSIONS: Systemic GDF-15 was higher in acutely admitted older medical patients with sarcopenia and frailty compared with patients without. The present study defined the optimum cut-off for GDF-15, related to the presence of sarcopenia and frailty, respectively. When elevated above the derived cutoffs, GDF-15 was strongly associated with frailty and sarcopenia in both crude and fully adjusted models.
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Biomarcadores , Fragilidade , Fator 15 de Diferenciação de Crescimento , Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Biomarcadores/sangue , Estudos Transversais , Fragilidade/sangue , Fator 15 de Diferenciação de Crescimento/sangue , Hospitalização , Estudos Prospectivos , Sarcopenia/sangue , Sarcopenia/diagnósticoRESUMO
Aim: Postmortem Computed Tomography (PMCT) is gradually introduced at forensic institutes. Image reconstruction software can increase diagnostic potential in CT by increasing distinction between structures and reduction of artifacts. The aim of this study was to develop and evaluate novel image reconstruction parameters for postmortem conditions, to increase image quality and diagnostic potential of CT scans. Method: Twenty PMCT scans of deceased hereof two in severe decay were subjected to four reconstruction techniques: a standard reconstruction algorithm, the detail reconstruction algorithm and two novel algorithms based on the standard algorithm, but with different Hounsfield settings. Image quality was evaluated by visual grading analysis (VGA) by four forensic radiologist observers. Results: The VGA did not prove that any of the reconstruction techniques were superior to the others. For standard and detail, the two pre-defined reconstruction algorithms, VGA scores were indiscernible and were superior to the equally indiscernible Hounsfield reconstructions on parameters translated into Sharpness and Low Contrast Resolution. The two alternative Hounsfield settings were superior with respect to Noise and Artifacts/Beam Hardening. Conclusion: The study elucidates the possiblity for multiple reconstructions specialized for PMCT conditions, to accommodate the special conditions when working with the deceased. Despite the lack of clear improvements in the tested reconstructions, this study provides an insight into some of the possibilities of improving PMCT quality using reconstruction techniques.
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The consequences of short-term disuse are well known, but effective countermeasures remain elusive. This study investigated the effects of neuromuscular electrical stimulation (NMES) during 5 days of bed rest on retaining lower limb muscle mass and muscle function in healthy young and old participants. One leg received NMES of the quadriceps muscle (3 × 30min/day) (NMES), and the other served as a control (CON). Isometric quadriceps strength (MVC), rate of force development (RFD), lower limb lean mass, and muscle thickness were assessed pre-and post-intervention. Muscle thickness remained unaltered with NMES in young and increased in old following bed rest, while it decreased in CON legs. In old participants, mid-thigh lean mass (MTLM) was preserved with NMES while decreased in CON legs. In the young, only a tendency to change with bed rest was detected for MTLM. MVC and early-phase RFD decreased in young and old, irrespective of NMES. In contrast, late-phase RFD was retained in young participants with NMES, while it decreased in young CON legs, and in the old, irrespective of NMES. NMES during short-term bed rest preserved muscle thickness but not maximal muscle strength. While young and old adults demonstrated similar adaptive responses in preventing the loss of skeletal muscle thickness, RFD was retained in the young only.
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Repouso em Cama , Força Muscular , Humanos , Repouso em Cama/efeitos adversos , Masculino , Força Muscular/fisiologia , Adulto , Feminino , Idoso , Músculo Quadríceps/fisiologia , Músculo Quadríceps/inervação , Músculo Esquelético/fisiologia , Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/métodos , Adulto Jovem , Contração Isométrica/fisiologia , Envelhecimento/fisiologia , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Abnormalities of resistance arteries may play essential roles in the pathophysiology of aging and hypertension. Deficiency of the vascular extracellular matrix protein MFAP4 (microfibrillar-associated protein 4) has previously been observed as protective against aberrant arterial remodeling. We hypothesized that MFAP4-deficiency would reduce age- and hypertension-dependent arterial changes in extracellular matrix composition and stiffening. METHODS: Mesenteric arteries were isolated from old (20-23 months) littermate Mfap4+/+ and Mfap4-/- mice, and 2-photon excitation microscopy imaging was used to quantify elastin and collagen volumes and dimensions in the vascular wall. Ten-week-old littermate Mfap4+/+ and Mfap4-/- mice were subjected to 20 days of continuous Ang II (angiotensin II) infusion and hypertension was monitored using invasive blood pressure measurements. Arterial stiffness, responses to vascular constrictors, and myogenic tone were monitored using wire- or pressure-myography. Collagen contents were assessed by Western blotting. RESULTS: MFAP4-deficiency significantly increased collagen volume and elastin fragmentation in aged mesenteric arteries without affecting arterial stiffness. MFAP4-deficient mice exhibited reduced diastolic pressure in Ang II-induced hypertension. There was no significant effect of MFAP4-deficiency on mesenteric artery structural remodeling or myogenic tone, although collagen content in mesenteric arteries was tendentially increased in hypertensive Mfap4+/+ mice relative to Mfap4-/- mice. Increased efficacy of vasoconstrictors (phenylephrine, thromboxane) and reduced stiffness were observed in Ang II-treated Mfap4-/- mouse mesenteric arteries in ex vivo myography recordings. CONCLUSIONS: MFAP4-deficiency reduces the elastin/collagen ratio in the aging resistance artery without affecting arterial stiffness. In contrast, MFAP4-deficiency reduces the stiffness of resistance arteries and ameliorates Ang II-induced hypertension.
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Envelhecimento , Angiotensina II , Proteínas da Matriz Extracelular , Hipertensão , Artérias Mesentéricas , Resistência Vascular , Rigidez Vascular , Animais , Camundongos , Envelhecimento/fisiologia , Angiotensina II/farmacologia , Pressão Sanguínea/fisiologia , Colágeno/metabolismo , Modelos Animais de Doenças , Elastina/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/deficiência , Hipertensão/fisiopatologia , Hipertensão/metabolismo , Hipertensão/genética , Artérias Mesentéricas/fisiopatologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Camundongos Knockout , Resistência Vascular/fisiologia , Rigidez Vascular/fisiologia , Rigidez Vascular/efeitos dos fármacosRESUMO
Introduction: Inflammation is a significant contributor to cardiorenal morbidity and mortality in diabetic kidney disease (DKD). The pathophysiological mechanisms linking systemic, subacute inflammation and local, kidney injury-initiated immune maladaptation is partially understood. Methods: Here, we explored the expression of proinflammatory cytokines in patients with DKD; investigated mouse models of type 1 and type 2 diabetes (T2D); evaluated glomerular signaling in vitro; performed post hoc analyses of systemic and urinary markers of inflammation; and initiated a phase 2b clinical study (FRONTIER-1; NCT04170543). Results: Transcriptomic profiling of kidney biopsies from patients with DKD revealed significant glomerular upregulation of interleukin-33 (IL-33). Inhibition of IL-33 signaling reduced glomerular damage and albuminuria in the uninephrectomized db/db mouse model (T2D/DKD). On a cellular level, inhibiting IL-33 improved glomerular endothelial health by decreasing cellular inflammation and reducing release of proinflammatory cytokines. Therefore, FRONTIER-1 was designed to test the safety and efficacy of the IL-33-targeted monoclonal antibody tozorakimab in patients with DKD. So far, 578 patients are enrolled in FRONTIER-1. The baseline inflammation status of participants (N > 146) was assessed in blood and urine. Comparison to independent reference cohorts (N > 200) validated the distribution of urinary tumor necrosis factor receptor 1 (TNFR1) and C-C motif chemokine ligand 2 (CCL2). Treatment with dapagliflozin for 6 weeks did not alter these biomarkers significantly. Conclusion: We show that blocking the IL-33 pathway may mitigate glomerular endothelial inflammation in DKD. The findings from the FRONTIER-1 study will provide valuable insights into the therapeutic potential of IL-33 inhibition in DKD.
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Purpose To investigate the effect of benzalkonium chloride (BAK)-preserved latanoprost and bimatoprost, polyquad (PQ)-preserved travoprost, and preservative-free (PF) latanoprost and tafluprost, all prostaglandin analogues (PGAs), on human conjunctival goblet cell (GC) survival. Furthermore, to investigate the effect of BAK-preserved and PF latanoprost on the cytokine secretion from GC. Methods Primary human conjunctival GCs were cultivated from donor tissue. Lactate dehydrogenase (LDH) and tetrazolium dye colorimetric (MTT) assays were used for the assessment of GC survival. A cytometric bead array was employed for measuring secretion of interleukin (IL)-6 and IL-8 from GC. Results BAK-preserved latanoprost and bimatoprost reduced cell survival by 28% (p = 0.0133) and 20% (p = 0.0208), respectively, in the LDH assay compared to a negative control. BAK-preserved latanoprost reduced cell proliferation by 54% (p = 0.003), BAK-preserved bimatoprost by 45% (p = 0.006), PQ-preserved travoprost by 16% (p = 0.0041), and PF latanoprost by 19% (p = 0.0001), in the MTT assay compared to a negative control. Only PF tafluprost did not affect the GCs in either assay. BAK-preserved latanoprost caused an increase in the secretion of pro-inflammatory IL-6 and IL-8 (p = 0.0001 and p = 0.0019, respectively) compared to a negative control, which PF latanoprost did not. Conclusion BAK-preserved PGA eye drops were more cytotoxic to GCs than PQ-preserved and PF PGA eye drops. BAK-preserved latanoprost induced an inflammatory response in GC. Treatment with PF and PQ-preserved PGA eye drops could mean better tolerability and adherence in glaucoma patients compared to treatment with BAK-preserved PGA eye drops. (AU)