Plasminogen activator inhibitor-1 is involved in glucocorticoid-induced decreases in angiogenesis during bone repair in mice

INTRODUCTION

Glucocorticoids delay fracture healing and induce osteoporosis. Angiogenesis plays an important role in bone repair after bone injury. Plasminogen activator inhibitor-1 (PAI-1) is the principal inhibitor of plasminogen activators and an adipocytokine that regulates metabolism. However, the mechanisms by which glucocorticoids delay bone repair remain unclear.

MATERIALS AND METHODS

Therefore, we herein investigated the roles of PAI-1 and angiogenesis in glucocorticoid-induced delays in bone repair after femoral bone injury using PAI-1-deficient female mice intraperitoneally administered dexamethasone (Dex).

RESULTS

PAI-1 deficiency significantly attenuated Dex-induced decreases in the number of CD31-positive vessels at damaged sites 4 days after femoral bone injury in mice. PAI-1 deficiency also significantly ameliorated Dex-induced decreases in the number of CD31- and endomucin-positive type H vessels and CD31-positive- and endomucin-negative vessels at damaged sites 4 days after femoral bone injury. Moreover, PAI-1 deficiency significantly mitigated Dex-induced decreases in the expression of vascular endothelial growth factor as well as hypoxia inducible factor-1α, transforming growth factor-β1, and bone morphogenetic protein-2 at damaged sites 4 days after femoral bone injury.

CONCLUSION

The present results demonstrate that Dex-reduced angiogenesis at damaged sites during the early bone-repair phase after femoral bone injury partly through PAI-1 in mice.

The causal impact of gut microbiota on circulating adipokine concentrations: a two-sample Mendelian randomization study

PURPOSE

Evidence from previous experimental and observational research demonstrates that the gut microbiota is related to circulating adipokine concentrations. Nevertheless, the debate as to whether gut microbiome composition causally influences circulating adipokine concentrations remains unresolved. This study aimed to take an essential step in elucidating this issue.

METHODS

We used two-sample Mendelian randomization (MR) to causally analyze genetic variation statistics for gut microbiota and four adipokines (including adiponectin, leptin, soluble leptin receptor [sOB-R], and plasminogen activator inhibitor-1 [PAI-1]) from large-scale genome-wide association studies (GWAS) datasets. A range of sensitivity analyses was also conducted to assess the stability and reliability of the results.

RESULTS

The composite results of the MR and sensitivity analyses revealed 22 significant causal associations. In particular, there is a suggestive causality between the family Clostridiaceae1 (IVW: β = 0.063, P = 0.034), the genus Butyrivibrio (IVW: β = 0.029, P = 0.031), and the family Alcaligenaceae (IVW: β=-0.070, P = 0.014) and adiponectin. Stronger causal effects with leptin were found for the genus Enterorhabdus (IVW: β=-0.073, P = 0.038) and the genus Lachnospiraceae (NK4A136 group) (IVW: β=-0.076, P = 0.01). Eight candidate bacterial groups were found to be associated with sOB-R, with the phylum Firmicutes (IVW: β = 0.235, P = 0.03) and the order Clostridiales (IVW: β = 0.267, P = 0.028) being of more interest. In addition, the genus Roseburia (IVW: β = 0.953, P = 0.022) and the order Lactobacillales (IVW: β=-0.806, P = 0.042) were suggestive of an association with PAI-1.

CONCLUSION

This study reveals a causal relationship between the gut microbiota and circulating adipokines and may help to offer novel insights into the prevention of abnormal concentrations of circulating adipokines and obesity-related diseases.

Plasminogen Activator Inhibitor-1 4G/5G Promoter Polymorphism in Indian Patients with Deep Vein Thrombosis

A single guanosine deletion/insertion (4G/5G) polymorphism in the promoter region of plasminogen activator inhibitor-1 (PAI-1) gene encoding PAI-1 protein has been investigated in deep vein thrombosis (DVT) patients. The association between PAI-1 4G/5G polymorphism and increased risk of DVT has been reported in some studies, while others have reported a lack of association. The present study aimed to investigate if the PAI-1 4G/5G polymorphism is associated with an increased risk of DVT in the Indian population and to assess its association with thrombophilic risk factors. Fifty-two adult patients with a history of chronic or recurrent DVT and 52 healthy adult controls were genotyped for PAI-1 4G/5G polymorphism. Plasma levels of PAI-1 and other thrombophilic risk factors were also measured. PAI-1 4G/5G polymorphism was not significantly associated with an increased risk of DVT. Protein C deficiency was significantly associated with the 4G/4G genotype. Patients with the 4G/4G genotype had significantly reduced PAI-1 levels as compared to the controls. PAI-1 4G/5G polymorphism did not significantly contribute to an increased risk of DVT in the Indian population. However, in the presence of thrombophilic risk factor abnormalities, the risk of DVT is increased in individuals with the 4G/4G genotype in the Indian cohort.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12288-023-01660-3.

Critical roles of PAI-1 in lipopolysaccharide-induced acute lung injury

PURPOSE

Plasminogen activator inhibitor-1 (PAI-1) is the main inhibitor of fibrinolytic systems. The effect of PAI-1 on inflammatory response is still inconsistent. Our study was conducted to investigate its effects on inflammation to clarify the role of PAI-1 in acute lung injury (ALI) induced by lipopolysaccharide (LPS).

MATERIAL AND METHODS

ALI models were established in wild-type (WT) and PAI-1 knockout (KO) mice by LPS intervention for 48 ​h. Lung histopathology, wet-dry ratio, total cell count and TNF-α concentration in bronchoalveolar lavage fluid (BALF), and inflammation related proteins were detected. Flow cytometry was used to sort neutrophils, macrophages, regulatory T cells (Treg) and T helper cell 17 (Th17). RNA sequencing was performed to find differentially expressed genes. Masson staining and immunohistochemistry were used to analyze pulmonary fiber deposition and proliferation.

RESULTS

Compared with ALI (WT) group, the wet-dry ratio, the total number of BALF cells, the concentration of TNF-α in BALF, and the expression of pp65 in the lung tissue was increased in ALI (PAI-1 KO) group, with increased proportion of neutrophils, decreased proportion of macrophages and decreased proportion of Treg/Th17 in the lung tissue. Collagen fiber deposition and PCNA expression were lighter in ALI (PAI-1 KO) group than ALI (WT) group. PPI analysis showed that PAI-1 was closely related to TNF, IL-6, IL-1β, Smad2/3 and mainly concentrated in the complement and coagulation system, TNF-α and IL-17 signaling pathways.

CONCLUSIONS

PAI-1 KO could aggravate ALI induced by LPS at 48 ​h. PAI-1 may be an important target to improve the prognosis of ALI.

No Observed Difference in Inflammatory and Coagulation Markers Following Diets Rich in n-6 Polyunsaturated Fat vs Monounsaturated Fat in Adults With Untreated Hypercholesterolemia: A Randomized Trial

BACKGROUND

Inflammatory and prothrombotic responses are hallmark to the progression of cardiovascular disease and may be influenced by the type of dietary fat. Cottonseed oil (CSO) is rich in n-6 polyunsaturated fats and improves traditional cardiovascular disease risk factors such as cholesterol profiles. However, some clinicians are still hesitant to promote n-6 polyunsaturated fats consumption despite growing evidence suggesting they may not be independently pro-inflammatory.

OBJECTIVE

To investigate the inflammatory and coagulation marker responses to an 8-week diet intervention rich in either CSO or olive oil (OO) (OO is rich in monounsaturated fat) in adults with untreated hypercholesterolemia.

DESIGN

This was a secondary analysis of a parallel-arm randomized clinical trial with the main outcome of cholesterol measures.

PARTICIPANTS/SETTING

Participants included in this analysis were 42 sedentary adults aged 30 to 75 years (62% women) in the Athens, GA, area, between May 2018 and June 2021, with untreated hypercholesterolemia or elevated blood lipids and body mass index >18.5. Hypercholesterolemia was defined as at least two blood lipid levels in a borderline undesirable/at risk range (total cholesterol level ≥180 mg/dL, low-density lipoprotein cholesterol level ≥110 mg/dL, high-density lipoprotein cholesterol level <50 mg/dL, or triglyceride level ≥130 mg/dL), or at least one in an undesirable range (total cholesterol level ≥240 mg/dL, low-density lipoprotein cholesterol level ≥160 mg/dL, high-density lipoprotein cholesterol level <40 mg/dL, or triglyceride level ≥200 mg/dL).

INTERVENTION

Participants were randomly assigned to either the CSO or OO group in a partial outpatient feeding trial. Meals from the study provided approximately 60% of their energy needs with 30% of energy needs from either CSO or OO for 8 weeks. Participants fulfilled their remaining energy needs with meals of their choosing.

MAIN OUTCOME MEASURES

Fasting plasma concentrations of inflammatory markers, including C-reactive protein, tumor necrosis factor-α, interleukin-6, and interleukin-1β were measured at baseline and 8 weeks. Markers of coagulation potential, including plasminogen activator inhibitor-1, and tissue factor were measured at the same time points.

STATISTICAL ANALYSES PERFORMED

Repeated measures linear mixed models were used with treatment and visit in the model for analyses of all biochemical markers.

RESULTS

There were no significant differences in fasting C-reactive protein (P = 0.70), tumor necrosis factor-α (P = 0.98), interleukin-6 (P = 0.21), interleukin-1β (P = 0.13), plasminogen activator inhibitor-1 (P = 0.29), or tissue factor (P = 0.29) between groups across the intervention.

CONCLUSIONS

Inflammation and coagulation marker responses to diets rich in CSO vs OO were not significantly different between groups, and neither group showed changes in these markers in adults with untreated hypercholesterolemia. This provides additional evidence suggesting that dietary n-6 polyunsaturated fats may not promote inflammation compared with monounsaturated fatty acids, even in adults at increased risk for cardiovascular disease.

Involvement of plasminogen activator inhibitor-1 in p300/p53-mediated age-related atrial fibrosis

Plasminogen activator inhibitor-1 (PAI-1), a key regulator of the fibrinolytic system, is also intimately involved in the fibrosis. Although PAI-1 may be involved in the occurrence of atrial fibrillation (AF) and thrombosis in the elderly, but whether it participated in aging-related atrial fibrosis and the detailed mechanism is still unclear. We compared the transcriptomics data of young (passage 4) versus senescent (passage 14) human atrial fibroblasts and found that PAI-1 was closely related to aging-related fibrosis. Aged mice and senescent human and mouse atrial fibroblasts underwent electrophysiological and biochemical studies. We found that p300, p53, and PAI-1 protein expressions were increased in the atrial tissue of aged mice and senescent human and mouse atrial fibroblasts. Curcumin or C646 (p300 inhibitor), or p300 knockdown inhibited the expression of PAI-1 contributing to reduced atrial fibroblasts senescence, atrial fibrosis, and the AF inducibility. Furthermore, p53 knockdown decreased the protein expression of PAI-1 and p21 in senescent human and mouse atrial fibroblasts. Our results suggest that p300/p53/PAI-1 signaling pathway participates in the mechanism of atrial fibrosis induced by aging, which provides new sights into the treatment of elderly AF.

Pharmacological inhibition of plasminogen activator inhibitor-1 prevents memory deficits and reduces neuropathology in APP/PS1 mice

RATIONALE

Extracellular proteolytic activity plays an important role in memory formation and the preservation of cognitive function. Previous studies have shown increased levels of plasminogen activator inhibitor-1 (PAI-1) in the brain of mouse models of Alzheimer's disease (AD) and plasma of AD patients, associated with memory and cognitive decline; however, the exact function of PAI-1 in AD onset and progression is largely unclear.

OBJECTIVE

In this study, we evaluated a novel PAI-1 inhibitor, TM5A15, on its ability to prevent or reverse memory deficits and decrease Aβ levels and plaque deposition in APP/PS1 mice.

METHODS

We administered TM5A15 mixed in a chow diet to 3-month and 9-month-old APP/PS1 mice before and after neuropathological changes were distinguishable. We then evaluated the effects of TM5A15 on memory function and neuropathology at 9 months and 18 months of age.

RESULTS

In the younger mice, 6 months of TM5A15 treatment protected against recognition and short-term working memory impairment. TM5A15 also decreased oligomer levels and amyloid plaques, and increased mBDNF expression in APP/PS1 mice at 9 months of age. In aged mice, 9 months of TM5A15 treatment did not significantly improve memory function nor decrease amyloid plaques. However, TM5A15 treatment showed a trend in decreasing oligomer levels in APP/PS1 mice at 18 months of age.

CONCLUSION

Our results suggest that PAI-1 inhibition could improve memory function and reduce the accumulation of amyloid levels in APP/PS1 mice. Such effects are more prominent when TM5A15 is administered before advanced AD pathology and memory deficits occur.

BIRC5: A novel therapeutic target for lung cancer stem cells and glioma stem cells

Baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5) is also known as survivin. BIRC5, a member of the apoptosis inhibitor (IAP) family, negatively regulates apoptosis or programmed cell death by inhibiting caspase activation. Due to these properties, overexpression of BIRC5 enables specific survival and division associated with cancer malignancies. In addition, BIRC5 is highly expressed in stem cells, but not present at all in terminally differentiated cells. On this basis, there is speculation that BIRC5 may be involved in the regulation of cancer stem cells (CSCs), but few study results have been reported. In addition, the molecular mechanisms of BIRC5 regulation are not yet well understood. Through the present study, it was confirmed that BIRC5 is a key factor regulating CSCs and epithelial to mesenchymal transition (EMT). BIRC5 was simultaneously overexpressed in lung cancer stem cells (LCSCs) and glioma stem cells (GSCs), and when the expression was suppressed, the characteristics of CSCs disappeared. In addition, plasminogen activator inhibitor-1 (PAI-1), a secreted factor regulated by BIRC5, is involved in signaling mechanisms that regulate cancer stem cells and EMT, and PAI-1 forms an autocrine chain. Based on these results, BIRC5 is proposed as a novel therapeutic target protein for LCSCs and GSCs.

Ziqi Dihuang decoction ameliorates thrombosis in septic rats by inhitbiting plasminogen activator inhibitor-1

Introduction

Sepsis is now a global medical burden with high morbility and mortality. The focus of this study was to evaluate the effects of Ziqi Dihuang (ZQDH) decoction on inflammatory and thrombosis-related parameters in septic rats.

Mothods

A rat model of sepsis was established by cecal ligation and puncture (CLP). Male Sprague-Dawley rats were randomly divided into Sham group, CLP group, ZQDH-1ow group (0.735 g/kg) and ZQDH-high group (1.47 g/kg). Rats in ZQDH groups were given ZQDH decoction by gavage for 7 days before CLP. White blood cells (WBC), inflammatory cell infiltration of liver, kidney and lung, as well as serum levels of tumor necrosis factor (TNF-α), interleukin-6 (IL-6) and reactive oxygen species (ROS) were used to assess systemic inflammatory response. Coagulation and fibrinolytic indexes included platelet count, coagulation function, fibrin deposition, and levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) in serum, liver, kidney and lung.

Results

LPS rats showed significant changes in inflammatory and thrombosis-related parameters such as increased WBC and inflammatory factors, decreased platelet counts, and increased tPA and PAI-1 concentrations in serum and organs. ZQDH decoction pretreatment can significantly inhibit the infiltration of inflammatory cells in the lung, and inhibit the production of TNF-α, IL-6 and ROS in a dose-dependent manner. ZQDH decoction also ameliorated thrombocytopenia, renal fibrin deposition, and tPA and PAI-1 levels in serum and organs.

Conclusion

These results suggest that ZQDH decoction can dose-dependently relieve systemic inflammatory injury and regulate fibrinolysis system in septic rats, which may be mediated by PAI-1.

Site-specific PEGylation of recombinant tissue-type plasminogen activator

Tissue-type plasminogen activator (tPA) is the gold standard for emergency treatment of ischemic stroke, which is the third leading cause of death worldwide. Major challenges of tPA therapy are its rapid elimination by plasminogen activator inhibitor-1 (PAI-1) and hepatic clearance, leading to the use of high doses and consequent serious side effects, including internal bleeding, swelling and low blood pressure. In this regard, we developed three polyethylene glycol (PEG)ylated tPA bioconjugates based on the recombinant human tPA drug Alteplase using site-specific conjugation strategies. The first bioconjugate with PEGylation at the N-terminus of tPA performed by reductive alkylation showed a reduced proteolytic activity of 68 % compared to wild type tPA. PEGylation at the single-free cysteine of tPA with linear and branched PEG revealed similar proteolytic activities as the wild-type protein. Moreover, both bioconjugates with PEG-cysteine-modification showed 2-fold slower inhibition kinetics by PAI-1. All bioconjugates increased in hydrodynamic size as a critical requirement for half-life extension.

Roles of four targets in the pathogenesis of graves' orbitopathy

Graves' orbitopathy (GO) is an autoimmune disease that involves complex immune systems. The mainstays of clinical management for this disease are surgery, targeted drugs therapy, and no-targeted drugs drug therapy. targeted drugs can improve therapeutic efficacy and enhance the quality of life for GO patients. However, as a second-line treatment for GO, targeted drugs such as tocilizumab and rituximab have very limited therapeutic effects and may be accompanied by side effects. The introduction of Teprotumumab, which targets IGF-IR, has made significant progress in the clinical management of GO. The pathophysiology of GO still remains uncertain as it involves a variety of immune cells and fibroblast interactions as well as immune responses to relevant disease targets of action. Therfore, learning more about immune response feedback pathways and potential targets of action will assist in the treatment of GO. In this discussion, we explore the pathogenesis of GO and relevant work, and highlight four potential targets for GO: Interleukin-23 receptor (IL-23 R), Leptin receptor (LepR), Orbital fibroblast activating factors, and Plasminogen activator inhibitor-1 (PAI-1). A deeper understanding of the pathogenesis of GO and the role of potential target signaling pathways is crucial for effective treatment of this disease.

A ketogenic diet containing medium-chain triglycerides reduces REM sleep duration without significant influence on mouse circadian phenotypes

Ketogenic diets (KDs) affect the circadian rhythms of behavior and clock gene expression in experimental animals. However, these diets were designed to simulate a fasting state; thus, whether these effects are caused by diet-induced ketogenesis or persistent starvation is difficult to distinguish. The present study aimed to define the effects of a KD containing medium-chain triglycerides (MCT-KD) that increase blood ketone levels without inducing carbohydrate starvation, on circadian rhythms and sleep regulation. Mice were fed with a normal diet (CTRL) or MCT-KD for 2 weeks. Blood β-hydroxybutyrate levels were significantly increased up to 2 mM by the MCT-KD, whereas body weight gain and blood glucose levels were identical between the groups, suggesting that ketosis accumulated without carbohydrate starvation in the MCT-KD mice. Circadian rhythms of wheel-running activity and core body temperature were almost identical, although wheel-running was slightly reduced in the MCT-KD mice. The circadian expression of the core clock genes, Per1, Per2, Bmal1, and Dbp in the hypothalamus, heart, liver, epididymal adipose tissues, and skeletal muscle were almost identical between the CTRL and MCT-KD mice, whereas the amplitude of hepatic Per2 and adipose Per1 expression was increased in MCT-KD mice. The MCT-KD reduced the duration of rapid-eye-movement (REM) sleep without affecting the duration of non-REM sleep and the duration of wakefulness. These findings suggested that the impact of ketone bodies on circadian systems are limited, although they might reduce locomotor activity and REM sleep duration.

Associations of circulating levels of phthalate metabolites with cytokines and acute phase reactants in a Spanish human cohort

The associations between human phthalate exposure and the onset of chronic diseases with an immunological component (e.g., metabolic syndrome, cancer) remain unclear, partly due to the uncertainties in the underlying mechanisms. This study investigates cross-sectional associations of the concentrations of 10 phthalate metabolites with 19 cytokines and acute phase proteins in 213 serum samples of Spanish adults. The associations were explored by Spearman's correlation, multivariable linear regression, and weighted quantile sum regression analyses. In the multivariable analyses, levels of plasminogen activator inhibitor (PAI)-1 were positively associated with mono-n-butyl phthalate (fold-change per one IQR increase in phthalate levels, 95% Confidence Interval: 1.65, 1.45-1.88) and mono-iso-butyl phthalate (3.07, 2.39-3.95), mono-ethyl phthalate (2.05, 1.62-2.61), as well as categorized mono-iso-decyl and mono-benzyl phthalates. The same phthalates also were significantly associated with leptin, interleukin (IL)-18 and monocyte chemoattractant protein-1. Moreover, the proinflammatory markers IL-1β, IL-17, IL-8, IL-6, IL-12, tumor necrosis factor, and lipopolysaccharide-binding protein showed positive and negative associations with, respectively, mono-(2-ethyl-hexyl) and mono-methyl phthalates. Finally, phthalate mixtures were positively associated with PAI-1, leptin, IL-18, IL-12, IL-8 and IL-1β. Despite the cross-sectional design limitation, these associations point to relevant subclinical immuno-inflammatory actions of these pollutants, warranting confirmation in future studies.

Laboratory evaluation of a new integrative assay to phenotype plasma fibrinolytic system

BACKGROUND

There is currently no universal and standardized test available to phenotype plasma fibrinolytic system.

AIMS

Our main aims were to evaluate the performances of the 'global fibrinolysis capacity' assay (GFC) performed with the Lysis Timer® instrument, and to study the influence of some preanalytical conditions.

METHOD

Euglobulin clot lysis time (ECLT) and GFC were performed under several preanalytical conditions.

RESULTS

GFC showed satisfactory intra- and inter-run precision. Frozen controls and reagents showed stability over the studied period. There was no statistically significant difference between GFC assessed in plasma samples processed at 4 °C or at 20 °C. GFC assessed with frozen-thawed plasma samples was prolonged when compared to fresh samples (p = 0.014). The centrifugation scheme had no influence on PAI-1 activity levels, GFC and ECLT. Reference interval for GFC ranges from 29.3 (C I90% = 26.9-31.9) to 49.5 (90% CI = 45.9-52.2) minutes. In addition, a preliminary study in 40 healthy volunteers and 43 adult patients referred for investigation of a bleeding disorder was conducted to compare GFC and ECLT assays in their ability to classify samples with shortened or prolonged clot lysis times. Disagreements between ECLT and GFC were observed for 23 samples (out of 83), most of them minor.

CONCLUSION

GFC is suitable and convenient for a broad clinical use and can be performed with frozen-thawed plasma samples. Unlike ECLT, GFC is designed to take into account the balance between inhibitors and activators of the fibrinolytic system and could detect both hypo- and hyperfibrinolytic states. Whether it is as suitable as or even better than ECLT to detect a bleeding tendency due to a hyperactive fibrinolytic system deserves to be properly investigated.

Association between short-term exposure to ambient air pollution and biomarkers of coagulation: A systematic review and meta-analysis

Ambient air pollution is one of the major global risk factors for cardiovascular health, and coagulation changes have been proposed to mediate this risk. Plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor (vWF), soluble P-selectin (sP-selectin) and tissue plasminogen activator (t-PA) are major coagulation biomarkers. However, there has been no systematic meta-analysis to summarize associations of ambient air pollution with these coagulation biomarkers. To assess the overall associations between ambient particulate matter (PM_2.5, PM₁₀), ozone (O₃), nitrogen dioxide (NO₂), carbon monoxide (CO) and major coagulation biomarkers including PAI-1, vWF, sP-selectin and t-PA based on the existing epidemiological research. We performed a systematic literature search of publications reporting the associations of ambient air pollutants (PM_2.5, PM₁₀, O₃, NO_2, and CO) with coagulation biomarkers (PAI-1, vWF, sP-selectin and t-PA) in PubMed, Web of Science, EMBASE, and Scopus databases as of April 5, 2022. Then, we performed a random-effect meta-analysis, which included 27 articles, and then identified the potential sources of heterogeneity. The pooled percent changes of coagulation biomarkers per 10 μg/m³ increase in short-term exposure to ambient PM_2.5 were 2.43% (95% CI: 0.59%, 4.29%) in PAI-1, 1.08% (95% CI: 0.21%, 1.96%) in vWF and 1.14% (95% CI: 0.59%, 1.68%) in sP-selectin, respectively. We also found significant associations of short-term exposure to ambient O₃ with PAI-1 (1.62%, 95% CI: 0.01%, 3.25%), sP-selectin (9.59%, 95% CI:2.78%, 16.86%) and t-PA (0.45%, 95% CI: 0.02%, 0.88%), respectively. Short-term exposures to ambient PM₁₀, NO₂ and CO were not significantly associated with changes in coagulation biomarkers. In conclusion, short-term exposures to PM_2.5 and O₃ are associated with significant increases in coagulation biomarkers, suggesting an activated coagulation state upon air pollution exposure.

Curcumin intervention during progressive fibrosis controls inflammatory cytokines and the fibrinolytic system in pulmonary fibrosis

Persistent injuries and chronic inflammation paired with dysregulated healing process in the lungs leads to scarring and stiffening of the tissue leading to a condition called pulmonary fibrosis. There is no efficacious therapy against the condition because of the poorly understood pathophysiology of the disease. Curcumin is well known anti-inflammatory natural compound and is shown to have beneficial effects in many diseases. It is also reported to show antifibrotic activities in pulmonary fibrosis. There are evidences that fibrinolytic system plays a crucial role in the development of pulmonary fibrosis. We aimed to see whether curcumin could regulate inflammation and fibrinolysis in murine model of pulmonary fibrosis. We prepared BLM induced pulmonary fibrosis model by administering BLM at a dose of 2 mg/ kg bodyweight. Curcumin (75 mg/kg body wt) was instilled intraperitoneally on different time points. The effect of curcumin on inflammatory cytokines and fibrinolytic system was studied using molecular biology techniques like RT-PCR, western blot and immunohistochemistry/immunofluorescence. We observed that BLM brought changes in the expressions of components in the fibrinolytic system, i.e. BLM favoured fibrin deposition by increasing the expression of PAI-1 (plasminogen activator inhibitor) and decreasing the expression of uPA (Urokinase plasminogen activator) and uPAR (Urokinase plasminogen activator receptor). We also demonstrate that curcumin could restore the normal expression of fibrinolytic components, uPA, uPAR and PAI-1. Curcumin could also minimize the expression of key enzymes in tissue remodeling in pulmonary fibrosis, MMP-2 and MMP-9, which were elevated in the BLM treated group. Our data suggest that curcumin exerts an anti-inflammatory and antifibrotic effect in lungs. We highlight curcumin as a feasible adjuvant therapy option against pulmonary fibrosis.

Phosphate and Cellular Senescence

Cellular senescence is one type of permeant arrest of cell growth and one of increasingly recognized contributor to aging and age-associated disease. High phosphate and low Klotho individually and synergistically lead to age-related degeneration in multiple organs. Substantial evidence supports the causality of high phosphate in cellular senescence, and potential contribution to human aging, cancer, cardiovascular, kidney, neurodegenerative, and musculoskeletal diseases. Phosphate can induce cellular senescence both by direct phosphotoxicity, and indirectly through downregulation of Klotho and upregulation of plasminogen activator inhibitor-1. Restriction of dietary phosphate intake and blockage of intestinal absorption of phosphate help suppress cellular senescence. Supplementation of Klotho protein, cellular senescence inhibitor, and removal of senescent cells with senolytic agents are potential novel strategies to attenuate phosphate-induced cellular senescence, retard aging, and ameliorate age-associated, and phosphate-induced disorders.

Plasminogen Activator Inhibitor-1 4G/5G Promoter Polymorphism in Adults with Splanchnic Vein Thrombosis: A Case-Control Study

The role of PAI-1 4G/5G polymorphism in venous thrombosis is unclear. PAI-1 4G/4G genotype is associated with elevated levels of PAI-1 resulting in a hypofibrinolytic state and hence increased thrombotic risk. In this study, we assessed the role of PAI-1 4G/5G promoter polymorphism in adult patients with splanchnic vein thrombosis. A total of 40 cases (portal vein thrombosis and Budd-Chiari syndrome) and 40 healthy controls were evaluated for the PAI-1 4G/5G polymorphism by amplification refractory mutation system polymerase chain reaction along with thrombophilia workup. The frequency of PAI-1 4G/4G homozygous, 4G/5G heterozygous and 5G/5G homozygous genotypes were 17.5%, 42.5% and 40%, respectively among cases and 22.5%, 50% and 27.5%, respectively among controls and the difference was not statistically significant (p = 0.61). The  PAI-1 4G/4G genotype was significantly associated with the cases with deranged thrombophilic risk factor (both inherited and acquired) (p = 0.02).

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12288-021-01454-5.

Role of plasminogen activator inhibitor-1 in muscle wasting induced by a diabetic state in female mice

Muscle wasting is a complication in patients with diabetes and leads to a reduced quality of life. However, the detailed mechanisms of diabetes-induced muscle wasting remain unknown. Plasminogen activator inhibitor-1 (PAI-1), a serine protease inhibitor that suppresses plasminogen activator activity, is involved in the pathophysiology of various diseases, including diabetes. In the present study, we examined the role of endogenous PAI-1 in the decrease in muscle mass and the impaired grip strength induced by the diabetic state by employing streptozotocin (STZ)-treated PAI-1-deficient female mice. The analyses of skeletal muscles and grip strength were performed in PAI-1-deficient and wild-type mice 4 weeks after the induction of a diabetic state by STZ administration. PAI-1 deficiency did not affect muscle mass in the lower limbs measured by quantitative computed tomography or tissue weights of the tibialis anterior, gastrocnemius and soleus muscles of female mice with or without STZ treatment. On the other hand, PAI-1 deficiency significantly aggravated grip strength decreased by STZ in female mice. PAI-1 deficiency did not affect the mRNA levels of Pax7, MyoD, myogenin or myosin heavy chain in either the tibialis anterior or soleus muscles of female mice with or without STZ treatment. In conclusion, we revealed for the first time that PAI-1 deficiency aggravates grip strength impaired by the diabetic state in female mice, although it did not affect diabetes-decreased muscle mass.

healthy controls: a systematic review and meta-analysis

INTRODUCTION

Major depressive disorder (MDD) is a severe mental health condition that affects millions of people worldwide. Etiologically, several factors may play a role in its development. Previous studies have reported elevated plasminogen activator inhibitor-1 (PAI-1) levels in patients with depression, suggesting that PAI-1 levels might be linked to the etiology of MDD.

METHODS

We systematically searched the following online databases: MEDLINE, Scopus, and Web of Science up to September 10, 2020, to identify studies in which PAI-1 levels were reported in subjects with MDD. Subsequently we used RevMan 5.3 to perform a meta-analysis of data extracted from the included studies using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and PICO criteria for the search and analysis.

RESULTS

Six studies that reported mean ± standard deviation (SD) were included in the analysis, with a total of 507 MDD patients and 3,453 controls. The overall standardized mean difference (SMD) was 0.27 (95% confidence interval [95% CI] 0.01-0.53). PAI-1 serum levels were 0.27 SDs higher in MDD patients than in controls. The test for overall effect was significant (z = 2.04, p = 0.04). Substantial heterogeneity was detected among the studies, demonstrated by the inconsistency test (I² = 72%) and the chi-square test (χ² = 18.32; p = 0.003).

CONCLUSIONS

This systematic review and meta-analysis showed that MDD might be related to elevated PAI-1 levels. We propose larger prospective clinical studies to further investigate this clinical correlation and validate the clinical significance of these observations.

Role of plasminogen activator inhibitor-1 in oral tongue squamous cell carcinoma: An immunohistochemical and in vitro analysis

OBJECTIVE

To evaluate the influence of plasminogen activator inhibitor-1 (PAI-1) on the biological behavior and prognosis of oral tongue squamous cell carcinoma (OTSCC).

METHODS

Immunoexpression of PAI-1 was analyzed in 60 OTSCC specimens and classified as low-expression (≤50% of positive cells) or high-expression (>50%). In vitro effects of recombinant human PAI-1 (rhPAI-1) were assessed through functional assays on the OTSCC-derived cell line SCC-25. Three cell groups were evaluated: G0 (control), G10 (10 nM rhPAI-1), and G20 (20 nM rhPAI-1).

RESULTS

High membrane expression of PAI-1 was associated with tumor budding (p = 0.046) and high-risk cases (p = 0.043). Cytoplasmic and membrane expression of PAI-1 was not associated with patient survival. Cell viability (p = 0.020) and progression to the S-phase of the cell cycle (p = 0.024) were higher in G10 and G20 at 24 h. The percentages of apoptotic/necrotic cells were not affected by rhPAI-1. The presence of rhPAI-1 increased cell migration (p = 0.039) and invasion (p = 0.039) after 24 and 72 h, respectively.

CONCLUSION

Our findings indicate the involvement of PAI-1 in the biological behavior of OTSCC, although its expression may not predict patient survival. The in vitro results suggest that PAI-1 stimulates cell proliferation, migration and invasion and may contribute to the aggressive phenotype of OTSCC.

Biomarkers of endothelial dysfunction and outcomes in coronavirus disease 2019 (COVID-19) patients: A systematic review and meta-analysis

BACKGROUND

Several studies have reported that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can directly infect endothelial cells, and endothelial dysfunction is often found in severe cases of coronavirus disease 2019 (COVID-19). To better understand the prognostic values of endothelial dysfunction in COVID-19-associated coagulopathy, we conducted a systematic review and meta-analysis to assess biomarkers of endothelial cells in patients with COVID-19.

METHODS

A literature search was conducted on online databases for observational studies evaluating biomarkers of endothelial dysfunction and composite poor outcomes in COVID-19 patients.

RESULTS

A total of 1187 patients from 17 studies were included in this analysis. The estimated pooled means for von Willebrand Factor (VWF) antigen levels in COVID-19 patients was higher compared to healthy control (306.42 [95% confidence interval (CI) 291.37-321.48], p < 0.001; I²:86%), with the highest VWF antigen levels was found in deceased COVID-19 patients (448.57 [95% CI 407.20-489.93], p < 0.001; I²:0%). Meta-analysis showed that higher plasma levels of VWF antigen, tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 antigen (PAI-1) antigen, and soluble thrombomodulin (sTM) were associated with composite poor outcome in COVID-19 patients ([standardized mean difference (SMD) 0.74 [0.33-1.16], p < 0.001; I²:80.4%], [SMD 0.55 [0.19-0.92], p = 0.003; I²:6.4%], [SMD 0.33 [0.04-0.62], p = 0.025; I²:7.9%], and [SMD 0.55 [0.10-0.99], p = 0.015; I²:23.6%], respectively).

CONCLUSION

The estimated pooled means show increased levels of VWF antigen in COVID-19 patients. Several biomarkers of endothelial dysfunction, including VFW antigen, t-PA, PAI-1, and sTM, are significantly associated with increased composite poor outcomes in patients with COVID-19.

PROSPERO REGISTRATION NUMBER

CRD42021228821.

Cadmium induces plasminogen activator inhibitor-1 via Smad2/3 signaling pathway in human endothelial EA.hy926 cells

Modulation of the blood coagulation fibrinolytic system is an essential function of vascular endothelial cells. Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) are major fibrinolytic regulatory proteins synthesized by vascular endothelial cells; fibrinolytic activity is dependent on the balance between these proteins. Previously, we have reported that cadmium, an initiator of ischemic heart disease, induces PAI-1 expression and suppresses fibrinolytic activity in cultured human vascular endothelial cells. However, the key molecules involved in cadmium-induced PAI-1 induction remain unclear. Herein, we investigated the contribution of Smad2 and Smad3, transcriptional factors involved in PAI-1 induction via transforming growth factor-β, using the human vascular endothelial cell line EA.hy926 cells in culture. Our findings indicated that cadmium induces PAI-1 expression without affecting t-PA expression up to 20 µM, a non-cytotoxic concentration, and PAI-1 induction by cadmium is partly mediated via Smad2 and Smad3. This study provides a possible mechanism underlying cadmium-induced vascular disorders.

Involvement of plasminogen activator inhibitor-1 and its related molecules in atrial fibrosis in patients with atrial fibrillation

Atrial fibrillation is the most common form of cardiac arrhythmia. Atrial fibrosis is a significant feature of atrial fibrillation though its mechanism is not well understood. We searched the Gene Expression Omnibus database to compare mRNA expression patterns between atrial fibrillation and sinus rhythm samples; one hundred and forty eight differentially expressed genes were identified. Most of these genes were significantly enriched in the extracellular matrix organization process and collagen-activated tyrosine kinase receptor signaling pathway. To screen hub genes involved in atrial fibrosis, we constructed a protein-protein interaction network and found that three hub genes (SERPINE1/plasminogen activator inhibitor-1/PAI-1, TIMP Metallopeptidase Inhibitor 3/TIMP3 and decorin/DCN) play vital roles in atrial fibrosis, especially plasminogen activator inhibitor-1. Elevated plasminogen activator inhibitor-1 expression was positively correlated with the p53 signaling pathway. Plasminogen activator inhibitor-1 and p53 protein expression levels were verified in patients with sinus rhythm and atrial fibrillation by Western blot analysis. Compared with the sinus rhythm controls, p53 and plasminogen activator inhibitor-1 protein expressions were upregulated in the atrial tissues of patients with atrial fibrillation. p53 was also found to regulate plasminogen activator inhibitor-1 based on the results of cellular and molecular experiments. Thus, the p53/plasminogen activator inhibitor-1 signaling axis may participate in the pathophysiological processes of atrial fibrillation, and plasminogen activator inhibitor-1 may serve as a new therapeutic biomarker in atrial fibrillation.

Hemostatic state of children with type 1 diabetes

PURPOSE

Hyperglycemia is one of the factors responsible for the molecular alterations that modify hemostasis. The aim of this study was to determine the levels of circulating molecules that have a prothrombotic impact on the child and adolescent population with type 1 diabetes mellitus.

METHODS

There were 35 patients with type 1 diabetes mellitus (11.0±2.5 years of age and a median 3.7±2.0 years of the disease) with no vascular complications and 20 healthy controls with similar age, sex, and body mass index included in the study. The evaluated parameters were fibrinogen, plasminogen activator inhibitor-1 (PAI1), von Willebrand factor antigen, and standard coagulation tests (platelet count, prothrombin time, and activated partial thromboplastin time). Glycemic control was evaluated by hemoglobin A1c and fasting blood glucose tests, and the presence of retinopathy and nephropathy was ruled out. The data obtained were analyzed by IBM SPSS Statistics ver. 20.0 and expressed as mean±standard deviation. The Pearson correlation coefficient was applied to investigate correlations between variables.

RESULTS

Diabetic patients showed significantly higher levels of fibrinogen (308±66 mg/dL vs. 246±18 mg/dL, P=0.0001), PAI-1 (41.6±12 ng/mL vs. 11.7±1.0 ng/mL, P=0.0001), and von Willebrand factor antigen (284%±55% vs. 121%±19%, P=0.0001). However, standard coagulation tests did not show differences between the 2 groups. PAI-1 was correlated with glycemia, hemoglobin A1c, fibrinogen, and von Willebrand factor antigen.

CONCLUSION

Elevated levels of fibrinogen, PAI-1, and von Willebrand factor antigen were found in the pediatric and adolescent population with type 1 diabetes mellitus, which suggests a prothrombotic state.

PAI-1 4G/4G Genotype Is Associated with Recurrent Implantation Failure: a Systematic Review and Meta-analysis

To detect the association between PAI-1 -675 4G/5G polymorphism and recurrent implantation failure (RIF). We performed this meta-analysis by searching databases of PubMed, EMBASE, OVID, and CNKI (China National Knowledge Infrastructure) for case-control studies that evaluated the association between PAI 4G/5G polymorphism and RIF. Meta-analysis was performed using the random-effects model. The odds ratios (ORs) with 95% confidence intervals (CIs) were reported to evaluate the association. Meta-regression and subgroup analysis were performed to explore the source of heterogeneity. Sensitivity analysis and trim-and-fill analysis were performed to explore the robustness of the meta-analysis. Eight case-control studies consisted of 1273 women were included in this meta-analysis (including 697 RIF patients and 576 control participants). The combined results showed that the homozygous genotype of PAI-1 -675 4G/4G was significantly associated with RIF (OR 2.79, 95%CI 1.53-5.08, P-value = 0.0008). Meta-regression and subgroup analysis showed that sample origin is the primary source of heterogeneity (P-value for meta-regression: 0.005). Study quality also explains some heterogeneity (P-value for meta-regression: 0.03). Sensitivity analysis showed that the result was not significantly changed after excluding one study each time. Trim-and-fill analysis showed that the result was not significantly changed after filled with three studies. PAI -675 4G/4G genotype may serve as one of the predisposing factors of RIF. Women with PAI-1 4G/4G genotype were at higher risk of RIF. However, more high-quality studies are needed to confirm the conclusion.

Retinal vasodilatory responses are inversely associated with plasminogen activator inhibitor-1: The African-PREDICT study

AIMS

Plasminogen activator inhibitor-1 (PAI-1), traditionally associated with fibrinolysis, is increasingly implicated in impaired vascular function. However, studies on its association with microvascular function are limited to the cutaneous and coronary microvascular beds in older and diseased individuals. To better understand its potential involvement in the early stages of disease development, we investigated the associations of retinal vasodilatory responses to flicker light with PAI-1 activity (PAI-1_act) in young and healthy individuals.

METHODS

We included healthy Black and White women and men (n = 518; aged 20-30 years), and measured plasma PAI-1_act and retinal vasodilatory responses to flicker light provocation. We also collected demographic and lifestyle data, measured blood pressure, anthropometry, blood lipids, inflammatory and other biomarkers.

RESULTS

In multivariate regression analyses, maximal retinal venular dilation associated independently and inversely with PAI-1_act (adj. R² = 0.11; β = -0.15; p = 0.001) in the total group. In exploratory subgroup analyses, this association remained in White women (adj. R² = 0.07; β = -0.23; p = 0.005), and was more robust with younger age and lower blood pressure and in non-smokers, but also with greater central adiposity, higher low-density lipoprotein cholesterol and inflammation (all p < 0.05).

CONCLUSIONS

Our data suggest that in young individuals, PAI-1 may already be associated with subclinical microvascular dysfunction.

Efficacy of Sanqi (Radix Notoginseng) in treating cerebral hemorrhage in rats with traumatic brain injury

OBJECTIVE

To evaluate the protective efficacy of Sanqi (Radix Notoginseng) on cerebral hemorrhage in a rat model of traumatic brain injury (TBI) by investigating plasminogen activator inhibitor-1 (PAI-1), tissue-type plasminogen activator (t-PA), nuclear factor-κB (NF-κB, p-p65), nitric oxide (NO), endothelin (ET), cluster differentiation (CD61CD62), and coagulation.

METHODS

The free-fall method was used to create a rat model of TBI. Forty-eight rats were randomly divided into six groups: the blank group, sham group, model group, low-dose Sanqi (Radix Notoginseng) group, middle-dose Sanqi (Radix Notoginseng) group, and high-dose Sanqi (Radix Notoginseng) group. At 24 h after the model was created, we investigated brain MRI, brain tissue morphology using HE staining, flow cytometry, and immunohistochemical changes.

RESULTS

Cerebral hemorrhage was aggravated in TBI rats (observed in brain specimens, brain MRI, and brain tissue HE). Cerebral immunohistochemistry results demonstrated that the expression of t-PA, PAI-1 and p-p65 increased significantly in TBI rats, while t-PA/PAI-1 had a significant decrease. In addition, CD61CD62, D2D, and ET were significantly increased in TBI rats, and PT and APTT were significantly prolonged; in contrast, NO was significantly decreased. Sanqi (Radix Notoginseng) decreased cerebral hemorrhage in TBI rats (observed in brain MRI and brain tissue HE), and increased t-PA/PAI-1, CD61CD62 significantly. It also significantly decreased the expression of t-PA, PAI-1, and p-p65 in brain immunohistochemistry and significantly decreased PT, APTT, D2D, and ET. However, there were no differences in NO between the model group and the Sanqi (Radix Notoginseng) group.

CONCLUSION

Sanqi (Radix Notoginseng) can decrease the expression of p-p65, increase t-PA/PAI-1, and stem traumatic intracranial hemorrhage in a TBI rat model.

Atrial fibrillation: the role of hypoxia-inducible factor-1-regulated cytokines

Atrial fibrillation (AF) is a common arrhythmia that has major morbidity and mortality. Hypoxia plays an important role in AF initiation and maintenance. Hypoxia-inducible factor (HIF), the master regulator of oxygen homeostasis in cells, plays a fundamental role in the regulation of multiple chemokines and cytokines that are involved in different physiological and pathophysiological pathways. HIF is also involved in the pathophysiology of AF induction and propagation mostly through structural remodeling such as fibrosis; however, some of the cytokines discussed have even been implicated in electrical remodeling of the atria. In this article, we highlight the association between HIF and some of its related cytokines with AF. Additionally, we provide an overview of the potential diagnostic benefits of using the mentioned cytokines as AF biomarkers. Research discussed in this review suggests that the expression of these cytokines may correlate with patients who are at an increased risk of developing AF. Furthermore, cytokines that are elevated in patients with AF can assist clinicians in the diagnosis of suspect paroxysmal AF patients. Interestingly, some of the cytokines have been elevated specifically when AF is associated with a hypercoagulable state, suggesting that they could be helpful in the clinician's and patient's decision to begin anticoagulation. Finally, more recent research has demonstrated the promise of targeting these cytokines for the treatment of AF. While still in its early stages, tools such as neutralizing antibodies have proved to be efficacious in targeting the HIF pathway and treating or preventing AF.

Drospirenone Effects on the Plasminogen Activator System in Immortalized Human Endometrial Endothelial Cells

Drospirenone (DRSP) is a fourth-generation progestin that interacts with the progesterone receptor (PR) and androgen receptor (AR) in addition to uniquely interacting to the mineralocorticoid receptor (MR). The known effects of DRSP via the mineralocorticoid receptor (MR) are limited. This study seeks to determine if DRSP alters plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) in human immortalized endometrial endothelial cells (HEEC) and if such changes in the plasminogen activator system (PAS) are mediated through the MR or AR. The in vitro cell culture experiments utilizing an immortalized human endometrial endothelial cell line evaluated two concentrations of DRSP on PAI-1 and tPA levels in the culture media using specific enzyme-linked immunoassays (ELISA). Experiments adding DRSP with an androgen receptor blocker, flutamide, or a mineralocorticoid receptor agonist, aldosterone, were performed to elucidate which receptor(s) mediated the PAS effects. DRSP 10 μM significantly decreased both HEEC levels of PAI-1 and tPA to 0.75 ± 0.04 and 0.82 ± 0.05 of control, respectively. These direct effects were blunted by flutamide, an AR antagonist. PAI-1 and tPA were not changed by the MR agonist, aldosterone. DRSP significantly decreased both PAI-1 and tPA in the HEECs via the androgen receptor.

Empagliflozin decreases the plasma concentration of plasminogen activator inhibitor-1 (PAI-1) in patients with type 2 diabetes: Association with improvement of fibrinolysis

AIMS

Elevation of the plasma concentration of plasminogen activator inhibitor-1 (PAI-1), a rapid-acting inhibitor of fibrinolysis, is associated with development of vascular thrombotic diseases, including coronary artery disease and stroke. We investigated the effects of empagliflozin, a sodium-glucose co-transporter-2 (SGLT2) inhibitor, on the plasma concentration of PAI-1 and fibrinolytic activity in patients with type 2 diabetes.

METHODS

In a randomized, active-controlled, open-label trial, 51 patients with type 2 diabetes were randomly allocated at a 2:1 ratio to receive empagliflozin (10 mg/day, n = 31) or standard therapy (n = 18) for 12 weeks. We measured the plasma concentrations of PAI-1 and plasmin-α2-antiplasmin complex (PAP) as indicators of fibrinolytic activity. Serum leptin and high-molecular weight (HMW) adiponectin were also measured.

RESULTS

In 49 patients who completed the trial, baseline plasma PAI-1 showed a positive correlation with body weight, visceral fat area (VFA), γ-glutamyltranspeptidase (GGT), leptin, and the platelet count, while it showed a negative correlation with HDL cholesterol and PAP. Body weight and VFA decreased significantly in the empagliflozin group, but not in the control group. The serum level of GGT showed a significant decrease at 12 weeks in the empagliflozin group, while it was unchanged in the control group. Serum HMW adiponectin increased significantly in the empagliflozin group. Plasma PAI-1 decreased significantly by 25% in the empagliflozin group, but not in the control group. In the empagliflozin group, the change of plasma PAI-1 was positively correlated with the changes of body weight and leptin, but was negatively correlated with the change of PAP.

CONCLUSIONS

Empagliflozin reduced the plasma PAI-1 concentration through its synergistic actions of a glucose-lowering effect, VFA loss, and restoring the adipokine balance. (Clinical trial registry: UMIN000025418).

Effects of lisinopril treatment on the pathophysiology of PCOS and plasminogen activator inhibitor-1 concentrations in rats

RESEARCH QUESTION

Angiotensin-converting enzyme inhibition results in a significant reduction in plasma concentrations of plasminogen activator inhibitor-1 (PAI-1). What are the effects of lisinopril treatment on PAI-1 concentrations and the morphology and function of the ovaries in the letrozole-induced polycystic ovary syndrome (PCOS) rat model?

DESIGN

This prospective randomized controlled animal study involved female Wistar albino rats. Twelve rats were assigned as controls (group I). In the study group (n = 48), letrozole (an aromatase inhibitor) was administered for PCOS modelling for 9 weeks. After confirming disrupted oestrous cycles, the study group was randomized into two groups: group II (n = 24; letrozole only) and group III (n = 24; letrozole + lisinopril 15 mg/kg per day). After 12 weeks, each group was divided randomly into two. Biochemical, histopathological and immunohistochemical analyses was performed in subgroups designated A, and fertilization rates were studied in subgroups designated B.

RESULTS

Lisinopril treatment reduced the weight and area of the ovaries, the number and wall thickness of cystic follicles, and serum concentrations of LH and testosterone, relative to group II (P < 0.001). Circulating PAI-1 concentrations were significantly different among three groups (7.7 ± 0.9 ng/ml, 9.8 ± 0.7 ng/ml and 8.6 ± 0.7 ng/ml for groups IA, IIA and IIIA; P < 0.001). Pregnancy rates were 100%, 0% and 16.7% in groups IB, IIB and IIIB.

CONCLUSIONS

In the letrozole-induced rodent PCOS model, lisinopril modifies the action of letrozole, possibly by inhibition of systemic and ovarian production of PAI-1. The use of PAI-1 inhibitors deserves further investigation in understanding the pathogenesis of PCOS.

Upregulated miR-224-5p suppresses osteoblast differentiation by increasing the expression of Pai-1 in the lumbar spine of a rat model of congenital kyphoscoliosis

Congenital scoliosis is defined by the presence of structural anatomical malformations that arise from failures of vertebral formation or segmentation before and after birth. The understanding of genetic background and key genes for congenital scoliosis is still poor. We herein report that the excess expression of plasminogen activator inhibitor-1 (Pai-1) induced by the upregulation of miR-224-5p is involved in the pathogenesis of congenital kyphoscoliosis through impaired osteoblast differentiation. We first investigated the variety and progression of abnormalities of the lumbar spines in Ishibashi (IS) rats, a rat model of congenital kyphoscoliosis. The rats had already shown fusion and division of the primary ossification center at postnatal day 4. Over time, the rats showed various abnormalities of the lumbar spine, including the fusion of the annular epiphyseal nucleus. At postnatal day 42, spinal curvature was clearly observed due to the fusion of the vertebral bodies. Using a microRNA array, we found that the expression of miR-224-5p was increased in the lumbar spine of the rats at postnatal day 4. The expression of Pai-1, which is involved in osteoblast differentiation regulated by miR-224-5p, was also increased, while the levels of type I collagen, a marker of osteoblast differentiation, were decreased in the lumbar spine. These results indicate that the aberrant expression of miRNA-224-5p and its target genes is involved in the impaired osteoblast differentiation and may provide a partial molecular explanation for the pathogenesis of congenital scoliosis.

Evaluation of plasminogen activator inhibitor-1 as a biomarker of unplanned revascularization and major adverse cardiac events in coronary angiography and percutaneous coronary intervention

BACKGROUND

The stented coronary artery remains at high-risk of complications, particularly in the form of stent thrombosis and in-stent restenosis. Improving our ability to identify patients at high-risk for these complications may provide opportunities for intervention. PAI-1 has been implicated in the pathophysiology of stent complications in preclinical studies, suggesting it may be a clinically valuable biomarker to predict adverse events following percutaneous coronary intervention.

METHODS

Plasma PAI-1 levels were measured in 910 subjects immediately after coronary angiography between 2015 and 2019. The primary outcome was the incidence of unplanned revascularization (UR) at 12 months. The secondary outcome was the incidence of major adverse cardiac events (MACE).

RESULTS

UR and MACE occurred in 49 and 103 patients in 12 months. Reduced plasma PAI-1 levels were associated with UR (4386.1 pg/mL [IQR, 2778.7-6664.6], n = 49, vs. 5247.6 pg/mL [IQR, 3414.1-7836.1], n = 861; p = 0.04). Tertile PAI-1 levels were predictive of UR after adjustment for known clinical risk factors associated with adverse outcomes. In post-hoc landmark analysis, UR was enhanced with low plasma PAI-1 levels for late complications (beyond 30 days). Finally, an updated systematic review and meta-analysis did not reveal an association between plasma PAI-1 and MACE.

CONCLUSION

PAI-1 levels are not independently associated with UR nor MACE in patients undergoing angiography but associated with UR following adjustment with known clinical factors. In our landmark analysis, low PAI-1 levels were associated with UR for late stent complications. As such, future studies should focus on the mediatory role of PAI-1 in the pathogenesis of stent complications.

Lupeol suppresses plasminogen activator inhibitor-1-mediated macrophage recruitment and attenuates M2 macrophage polarization

Tumor-associated macrophages (TAMs) are closely related with poor prognosis of cancers. The current study investigated whether lupeol regulates TAMs by focusing on the recruitment and polarization of macrophages. We found that lupeol suppressed the recruitment of THP-1 macrophages (THP-1 cells differentiated into macrophages) towards H1299 lung carcinoma cells by inhibiting plasminogen activator inhibitor-1 (PAI-1) production from H1299 cells. The reduced migration of THP-1 macrophages by lupeol was recovered by adding recombinant human PAI-1 as a chemoattractant. Knockdown of PAI-1 or treatment of tiplaxtinin, a PAI-1 inhibitor, in H1299 cells abrogated the chemotaxis of macrophages. Furthermore, lupeol suppressed the interleukin (IL)-4- and IL-13-induced M2 macrophage polarization. The mRNA expression of M2 macrophage markers and the phosphorylation of signal transducer and activator of transcription 6 (STAT6) were commonly decreased by lupeol in RAW264.7 cells. In addition, lupeol-suppressed M2 macrophage polarization led to the reduced migration of Lewis lung carcinoma (LLC) cells. Taken together, our results suggest that lupeol attenuates PAI-1-mediated macrophage recruitment towards cancer cells and inhibits M2 macrophage polarization.

Role of plasminogen activator inhibitor-1 in methotrexate-induced epithelial-mesenchymal transition in alveolar epithelial A549 cells

There is increasing evidence that epithelial-mesenchymal transition (EMT) contributes to the development of organ fibrosis. We demonstrated that methotrexate (MTX) clearly induced EMT through the transforming growth factor (TGF)-β-related signaling pathway in human alveolar epithelial cell line, A549. However, critical factors associated with MTX-induced EMT have not yet been identified. In our study, we attempted to identify factors playing a crucial role in MTX-induced EMT in A549 cells. We focused on plasminogen activator inhibitor-1 (PAI-1) as the possible target for the prevention of MTX-induced EMT-related lung injury. Comprehensive gene expression analysis by microarray revealed that mRNA expression level of PAI-1 was clearly increased by MTX treatment. In addition, using several cloned A549 cells, we found a good correlation between MTX-induced increase in mRNA expression levels of α-smooth muscle actin (SMA), a representative EMT marker, and PAI-1. Furthermore, MTX upregulated mRNA and protein expression levels of PAI-1 in A549 cells; this upregulation was canceled by co-treatment with SB431542, a TGF-β-related signaling pathway inhibitor. Notably, tiplaxtinin, a PAI-1 inhibitor, and knockdown of urokinase-type plasminogen activator receptor (uPAR) prevented MTX-induced EMT in A549 cells. These findings indicate that MTX may induce EMT via upregulation of PAI-1 expression and interaction of PAI-1 with uPAR in A549 cells.

PAI-1 is involved in delayed bone repair induced by glucocorticoids in mice

Glucocorticoid (GC) treatments induce osteoporosis and chronic GC treatments have been suggested to induce delayed bone repair; however, the mechanisms by which GC induces delayed bone repair remain unclear. We herein investigated the roles of plasminogen activator inhibitor-1 (PAI-1) in GC-induced effects on bone repair after femoral bone injury using female mice with a PAI-1 deficiency and their wild-type counterparts. Dexamethasone (Dex) increased plasma PAI-1 levels as well as PAI-1 mRNA levels in the adipose tissues and muscles of wild-type mice. PAI-1 deficiency significantly blunted Dex-induced delayed bone repair in mice. Moreover, PAI-1 deficiency significantly blunted Runx2 mRNA levels suppressed by Dex as well as Dex-induced osteoblast apoptosis at the damaged site 7 days after bone injury in mice. On the other hand, PAI-1 deficiency did not affect adipogenic gene expression enhanced by Dex at the damaged site 7 days after bone injury in mice. In conclusion, we herein showed for the first time that PAI-1 is involved in delayed bone repair after bone injury induced by GC in mice. PAI-1 may influence early stage osteoblast differentiation and apoptosis during the osteoblastic restoration phase of the bone repair process.

Triglyceride/HDL-cholesterol ratio and plasminogen activator inhibitor-1 independently predict high pulse pressure in sickle cell trait and disease

We hypothesised that TG/HDL-C ratio and PAI-1 would be associated with high pulse pressure (PP) in young adults with sickle cell trait (SCT) and sickle cell disease (SCD). We compared the clinical, biochemical, and cardiometabolic parameters among individuals with normal genotype (HbAA; n = 60), SCT (HbAS; n = 60), and SCD (HbSS; n = 60), all in steady state. Using multivariate linear regression analysis, high PP was positively related to TG/HDL-C ratio in SCT (β = 0.307; p = .014) and PAI-1 (β = 0.499; p = .001) in SCD. The curve of receiver operating characteristic also showed that TG/HDL-C ratio and PAI-1 are efficient predictors of high PP in SCT carriers and SCD patients, respectively. This study suggests that increased levels of TG/HDL-C ratio and PAI-1 may be salient risk factors that would promote the development of arterial stiffness and other CVD in SCT carriers and SCD patients.

Evaluation of p53 and Its Target Gene Expression as Potential Biomarkers of Cholangiocarcinoma in Thai Patients

BACKGROUND

Cholangiocarcinoma (CCA), a common cancer in northeastern Thailand, is a severe disease with poor prognosis and short survival time following diagnosis. DNA damage in CCA is believed to be caused by liver fluke infection in combination with exposure to carcinogens. p53, a tumor suppressor, is the most mutated gene in human cancers including liver fluke-associated CCA. Hence, expression patterns of p53 and its target genes may be useful for diagnosis and/or prognosis of CCA patients.

METHODS

Differential mRNA expression of p53 and its target genes, namely, FUCA1, ICAM2 MDM2, p21, PAI-1, S100A9, and WIP1 in CCA tissue samples (n = 30) relative to matched adjacent non-tumor tissues was determined by quantitative RT-PCR and compared to clinicopathological features. Level of p53 protein was determined by immunohistochemistry and correlated with the expression of its target genes.

RESULTS

Immunohistochemistry showed elevation of p53 protein level in 77% of the cases, while RT-PCR showed downregulation of p53 mRNA and its seven target genes in 23% and 47-97% of the samples. PAI-1 was down-regulated in almost all CCA samples, thus highlighting it as a potential diagnostic marker for CCA. However, no significant clinical associations were found except for down-regulation of WIP1 that was significantly correlated with non-papillary type tissue (p-value = 0.001) and with high p53 protein level (p-value = 0.007).

CONCLUSION

Our results demonstrated statistically significant association between down-regulation of WIP1 with non-papillary type and with high p53 protein level, and PAI-1 was down-regulated in almost all CCA. Therefore, expression level of WIP1 and PAI-1 may be useful for predicting p53 functional status and as a potential diagnostic marker of CCA, respectively.

Inhibition of plasminogen activator inhibitor-1 attenuates against intestinal fibrosis in mice

Background/Aims

Intestinal fibrosis is a major complication of Crohn’s disease (CD). The profibrotic protein transforming growth factor-β (TGF-β) has been considered to be critical for the induction of the fibrotic program. TGF-β has the ability to induce not only the expression of extracellular matrix (ECM) including collagen, but also the production of plasminogen activator inhibitor-1 (PAI-1) that prevents enzymatic degradation of the ECM during the onset of fibrotic diseases. However, the significance of PAI-1 in the developing intestinal fibrosis has not been fully understood. In the present study, we examined the actual expression of PAI-1 in fibrotic legion of intestinal inflammation and its correlation with the abnormal ECM deposition.

Methods

Chronic intestinal inflammation was induced in BALB/c mice using 8 repeated intrarectal injections of 2,4,6-trinitrobenzene sulfonic acid (TNBS). TM5275, a PAI-1 inhibitor, was orally administered as a carboxymethyl cellulose suspension each day for 2 weeks after the sixth TNBS injection.

Results

Using a publicly available dataset (accession number, GSE75214) and TNBS-treated mice, we observed increases in PAI-1 transcripts at active fibrotic lesions in both patients with CD and mice with chronic intestinal inflammation. Oral administration of TM5275 immediately after the onset of intestinal fibrosis upregulated MMP-9 (matrix metalloproteinase 9) and decreased collagen accumulation, resulting in attenuation of the fibrogenesis in TNBS-treated mice.

Conclusions

PAI-1-mediated fibrinolytic system facilitates collagen degradation suppression. Hence, PAI-1 inhibitor could be applied as an anti-fibrotic drug in CD treatment.

Correlation between PAI-1 rs1799889 polymorphism and venous thromboembolism: A meta-analysis of 48 case-control studies

BACKGROUND

We performed this meta-analysis to better assess the relationship between plasminogen activator inhibitor-1 (PAI-1) rs1799889 polymorphism and the risk of venous thromboembolism.

METHOD

Eligible studies were searched in PubMed, Medline, Embase, Web of Science and CNKI. Odds ratios with 95% confidence intervals were calculated.

RESULT

A total of 48 studies with 14,806 participants were analyzed. No positive results were detected in overall analyses. Further subgroup analyses revealed that the PAI-1 rs1799889 polymorphism was significantly associated with the risk of venous thromboembolism in Caucasians and East Asians. When we stratified available data according to type of disease, we found that the PAI-1 rs1799889 polymorphism was significantly correlated with the risk of DVT. No any other positive results were observed in overall and subgroup analyses.

CONCLUSION

Our findings indicate that the PAI-1 rs1799889 polymorphism may serve as a potential biological marker for venous thromboembolism in Caucasians and East Asians.

Circulating miR-30c as a predictive biomarker of type 2 diabetes mellitus with coronary heart disease by regulating PAI-1/VN interactions. Life Sci. 2019;239:117092. [PMID: 31760103 DOI: 10.1016/j.lfs.2019.117092]

AIMS

Type 2 diabetes mellitus (DM2) is associated with coronary heart disease (CHD) and is characterized by high levels of plasminogen activator inhibitor (PAI)-1. Circulating microRNAs have been reported as potential diagnostic biomarkers for DM2 and CHD. However, the underlying mechanisms have largely remained unclear.

MAIN METHODS

The changes of circulating miR-30c, PAI-1 and vitronetin (VN) in plasma from CHD, noncomplicated (NC) + DM2, CHD + DM2 subjects and control individuals were assessed by quantitative reverse transcription PCR (qRT-PCR) and ELISA assays, respectively. The effects of miR-30c on VN expression by targeting PAI-1 were assessed in vitro SMC and in ex vivo plasma, using bioinformatic analysis, miRNA transfection, luciferase assays, qRT-PCR and western blot, respectively.

KEY FINDINGS

We found that decreased circulating miR-30c was negatively correlated with the severity of coronary lesions and the resulting elevated PAI-1 and VN levels. Circulating miR-30c significantly distinguished between patients with CHD + DM2, NC + DM2, CHD and control subjects, and that were significantly associated with certain risk factors for progression from a normal individual to one with CHD + DM2. Furthermore, we also showed that miR-30c plays a previously unrecognized role in regulating the expression of VN levels via regulating PAI-1 levels in vitro SMC and in ex vivo plasma.

SIGNIFICANCE

These findings provide a novel regulatory mechanism of miR-30c in regulating PAI-1/VN interactions and that may serve as a diagnostic biomarker of DM2 that is complicated with CHD.

Performance of plasminogen activator inhibitor-1 as a biomarker in patients undergoing coronary angiography: Analytical and biological considerations

INTRODUCTION AND OBJECTIVE

Target lesion failure continues to limit the efficacy of percutaneous coronary intervention despite advancements in stent design and medical therapy. Identification of biomarkers to risk stratify patients after percutaneous coronary intervention has the potential to focus therapies on cohorts with increased benefits. Plasminogen activator inhibitor-1 has been identified as a candidate biomarker. Herein, we evaluate biological variables which impact plasminogen activator inhibitor-1 levels and analytical characteristics which impact its utility as a biomarker in humans.

METHODS

Plasma plasminogen activator inhibitor-1 was measured in 689 patients undergoing coronary angiography. Plasminogen activator inhibitor-1 levels were measured. Clinical and procedural characteristics were collected in a prospective registry.

RESULTS

Plasma plasminogen activator inhibitor-1 analytical (CV_a = 4.1%), intra-individual (CV_i = 44.0%) and inter-individual (CV_g = 118.6%) variations with reference change value of 122.3% were calculated. Plasminogen activator inhibitor-1 levels were elevated in patients with cardiovascular risk factors, including type 2 diabetes, pre-diabetes, smokers, obesity, hypertension, and daytime variation in procedure and blood draw.

CONCLUSION

Variation in plasma plasminogen activator inhibitor-1 levels is influenced by multiple biological and procedural characteristics. The performance of plasma plasminogen activator inhibitor-1 is consistent with biomarkers in clinical use (N-terminal pro-B-type natriuretic peptide and C-reactive protein) and its applicability is promising.

Inherited disorders of the fibrinolytic pathway

Deficiencies or excessive activation of the  fibrinolytic system can result in severe, lifelong bleeding disorders. The most severe clinical phenotype is caused by α2-Antiplasmin (α2-AP) deficiency which results in excess fibrinolysis due to the inability to inhibit plasmin. Another bleeding disorder due to a defect in the fibrinolytic pathway results from Plasminogen activator inhibitor-1 (PAI-1) deficiency causing enhanced fibrinolysis due to the decreased inhibition of plasminogen activators resulting in increased conversion of plasminogen to plasmin. Both these disorders are rare and have an autosomal recessive pattern of inheritance. They can remain undetected as routine coagulation and platelet function tests are normal. A unique gain-of-function defect in fibrinolysis causes the Quebec platelet disorder (QPD) which is characterized by profibrinolytic platelets containing increased urokinase-type plasminogen activator (uPA) in the α-granules. A high index of suspicion based on clinical phenotype along with the availability of specialized hemostasis testing is required for timely and accurate diagnosis. Antifibrinolytic agents, such as tranexamic acid or ε-aminocaproic acid, are the mainstays of treatment which inhibit fibrinolysis by preventing the binding of plasminogen to fibrin and thereby stabilizing the fibrin clot. The purpose of this review is to summarize the pathogenesis, clinical phenotype, approaches to diagnosis and treatment for these three major disorders of fibrinolysis.

Role of tissue plasminogen activator and plasminogen activator inhibitor as potential biomarkers in psychosis

The identification of biological markers for psychosis has an impact on its diagnosis, prognosis, and likelihood of treatment response. Tissue plasminogen activator (tPA) is involved in important functions such as synaptic plasticity, long-term potentiation and neurogenesis. Plasminogen activator inhibitor (PAI-1) is the most important inhibitor of tPA. Preliminary studies have shown that schizophrenia patients have lower tPA and higher PAI-1 levels than the general population. The association of tPA and PAI-1 abnormalities with psychotic spectrum disorders, however, remains elusive. Our primary objective was to assess the plasma levels of tPA and PAI-1 in patients experiencing acute psychotic episodes as compared to those in healthy controls. In this prospective case-control study, we collected peripheral blood samples from psychiatric inpatients and healthy age, gender and race-matched subjects and determined plasma levels of tPA and PAI-1 by enzyme-linked immune-absorbent assays. Plasma levels of PAI-1 in patients with schizoaffective disorder were significantly lower as compared to those in control subjects (P = 0.03). tPA was lower in cases as compared to controls although it did not reach statistical significance. Asian patients and controls had lower PAI-1 levels. Further, Asian patients with schizoaffective disorder had significantly lower PAI-1 level compared to Asian patients with schizophrenia. Our results indicate that patients with schizoaffective disorder have lower PAI-1 levels than those with schizophrenia, affective psychosis, and healthy controls. Further studies are warranted to explore the potential of PAI-1 as a biomarker for diagnosing schizoaffective disorder.

Suppression of plasminogen activator inhibitor-1 (PAI-1) activity by crocin ameliorates lipopolysaccharide-induced thrombosis in rats

The imbalance between clot formation and fibrinolysis is mainly attributed to increased levels of plasminogen activator inhibitor type 1 (PAI-1), an inhibitor of fibrinolysis closely involved in inflammatory responses such as septic shock. This increase is mediated by many factors, including reactive oxygen species (ROS). The present study was designed to evaluate the prophylactic effect of crocin, a potent natural antioxidant, on PAI-1 in the rat model of endotoxic shock. Lipopolysaccharide-infused rats (500 μg/kg) showed significant changes in thrombosis-related haematological parameters such as decrease of platelet blood counts and increase (7 fold) of PAI-1 concentration in blood plasma. No effect on t-PA activity was observed. Crocin administration in two different doses (10 mg/kg and 100 mg/kg) 30 min prior to the injection of LPS, inhibited the reduction of platelet counts and ameliorated the concentration of PAI-1 in the liver and the brain. Moreover, crocin inhibited the deposition of fibrin in the renal glomeruli. No significant changes were recorded in the healthy groups of crocin (10 mg/kg and 100 mg/kg) compared to the control group. These data demonstrate the potential of crocin to prevent LPS-induced organ injury and suggest it is worthwhile to investigate the use of antioxidants for the treatment of septicemia.

Ketamine ameliorates depressive-like behaviors by tPA-mediated conversion of proBDNF to mBDNF in the hippocampus of stressed rats

Some studies have indicated that ketamine has a rapid antidepressant effects, but the underlying molecular mechanism is still unclear. Researchers have found that mature brain-derived neurotrophic factor (mBDNF) and its precursor proBDNF are related to depression; they elicit opposite effects on cellular functions. It is clear that tissue plasminogen activator (tPA) is a key regulatory element in the conversion of proBDNF to mBDNF. The chronic unpredicted mild stress (CUMS) procedure is a classical and reliable method to establish the model of depression. This study found that sucrose preference and locomotor activity were both reduced in CUMS-treated rats while were increased in those who were injected with ketamine. The hippocampal proBDNF/mBDNF ratio was downregulated after ketamine treatment in those rats, together with an increased level of tPA in the hippocampus. However, tPA activity was unaltered after ketamine intraperitoneal injection. Intrahippocampal injection of active plasminogen activator inhibitor-1 (inhibitor of tPA) before ketamine treatment reversed the antidepressant effects and upregulated the proBDNF/mBDNF ratio. The results of this study suggest that the antidepressant action induced by ketamine may be related to tPA-mediated conversion of proBDNF to mBDNF in the hippocampus.

PAI-1 secreted from metastatic ovarian cancer cells triggers the tumor-promoting role of the mesothelium in a feedback loop to accelerate peritoneal dissemination

The mesothelium, covered by a continuous monolayer of mesothelial cells, is the first protective barrier against metastatic ovarian cancer. However, mesothelial cells release tumor-promoting factors that accelerate the process of peritoneal metastasis. We identified cancer-associated mesothelial cells (CAMs) that had tumor-promoting potential. Here, we found that plasminogen activator inhibitor-1 (PAI-1) induced the formation of CAMs, after which CAMs increasingly secreted the oncogenic factors interleukin-8 (IL-8) and C-X-C motif chemokine ligand 5 (CXCL5), further promoting the metastasis of ovarian cancer cells in a feedback loop. After the formation of CAMs, PAI-1 activated the nuclear factor kappa B (NFκB) pathway in the CAMs, thus transcriptionally upregulating the expression of the downstream NFκB targets IL-8 and CXCL5. Moreover, PAI-1 correlated with peritoneal metastasis in ovarian cancer patients and indicated a poor prognosis. In both ex vivo and in vivo models, after PAI-1 expression was knocked down, the metastasis of ovarian cancer cells decreased significantly. Therefore, targeting PAI-1 may provide a potential target for future therapeutics to prevent the formation of CAMs and alleviate peritoneal metastasis in ovarian cancer patients.

Rising plasminogen activator inhibitor-1 and hypoadiponectinemia characterize the cardiometabolic biomarker profile of women with recent gestational diabetes

BACKGROUND

Gestational diabetes (GDM) and milder gestational impaired glucose tolerance (GIGT) identify women at risk of developing type 2 diabetes and cardiovascular disease later in life. Accordingly, the postpartum years after gestational dysglycemia can provide insight into early events in the natural history of these disorders. We thus sought to prospectively evaluate the relationship between gestational glucose tolerance and emerging cardiometabolic biomarkers [adiponectin, chemerin, retinol-binding protein-4 (RBP-4), C-reactive protein (CRP), plasminogen activator inhibitor-1 (PAI-1)] at both 1- and 3-years postpartum in a cohort reflecting the full spectrum of gestational dysglycemia (from normal to GIGT to GDM).

METHODS

Three-hundred-and-thirty-nine women completed a glucose challenge test (GCT) and oral glucose tolerance test (OGTT) in pregnancy, which identified 4 gestational glucose tolerance groups: GDM (n = 105); GIGT (n = 59); abnormal GCT with normal OGTT (n = 99); and normal GCT with normal OGTT (n = 76). At 1- and 3-years postpartum, the women underwent repeat OGTT with measurement of biomarkers (adiponectin/chemerin/RBP-4/CRP/PAI-1).

RESULTS

Serum adiponectin was lower in women with GDM and GIGT at both 1-year and 3-years (both P ≤ 0.002), whereas chemerin, RBP-4, CRP and PAI-1 showed no differences across the 4 groups. Importantly, the change in PAI-1 between 1- and 3-years progressively increased from the normal GCT group to the abnormal GCT group to GIGT to GDM (P = 0.03). Indeed, both GDM (t = 2.98, P = 0.003) and GIGT (t = 2.14, P = 0.03) independently predicted an increase in PAI-1 from 1- to 3-years postpartum.

CONCLUSIONS

Hypoadiponectinemia and rising PAI-1 over time are early features of the cardiometabolic biomarker profile of women with recent gestational dysglycemia.

High ApoD protein level in the round ligament fat depot of severely obese women is associated with an improved inflammatory profile

PURPOSE

Apolipoprotein D (ApoD) is a lipocalin participating in lipid transport. It binds to a variety of ligands, with a higher affinity for arachidonic acid, and is thought to have a diverse array of functions. We investigated a potential role for ApoD in insulin sensitivity, inflammation, and thrombosis-processes related to lipid metabolism-in severely obese women.

METHODS

We measured ApoD expression in a cohort of 44 severely obese women including dysmetabolic and non-dysmetabolic patients. Physical and metabolic characteristics of these women were determined from anthropometric measurements and blood samples. ApoD was quantified at the mRNA and protein levels in samples from three intra-abdominal adipose tissues (AT): omental, mesenteric and round ligament (RL).

RESULTS

ApoD protein levels were highly variable between AT of the same individual. High ApoD protein levels, particularly in the RL depot, were linked to lower plasma insulin levels (-40%, p = 0.015) and insulin resistance (-47%, p = 0.022), and increased insulin sensitivity (+10%, p = 0.008). Lower circulating pro-inflammatory PAI-1 (-39%, p = 0.001), and TNF-α (-19%, p = 0.030) levels were also correlated to high ApoD protein in the RL AT.

CONCLUSIONS

ApoD variability between AT was consistent with different accumulation efficiencies and/or metabolic functions according to the anatomic location of fat depots. Most statistically significant correlations implicated ApoD protein levels, in agreement with protein accumulation in target tissues. These correlations associated higher ApoD levels in fat depots with improved metabolic health in severely obese women.