Aspirin inhibits MMP-2 and MMP-9 expression and activity through PPARalpha/gamma and TIMP-1-mediated mechanisms in cultured mouse celiac macrophages

Aspirin exposure coupled with hypoxia interferes energy metabolism, antioxidant and autophagic processes and causes liver injury in estuarine goby Mugilogobius chulae

Toxicity assessments of pollutants often overlook the impact of environmental factors like hypoxia, which can alter chemical toxicity with unexpected consequences. In this study, Mugilogobius chulae, an estuarine fish, was used to investigate the effects of hypoxia (H), aspirin (ASA), and their combination (H_ASA) exposure over 24, 72, and 168 h. We employed RNA-seq analysis, expression of key gene expression profiling, enzymatic activity assays, and histopathological and ultrastructural examinations of liver tissue to explore the effects and mechanisms of ASA-coupled hypoxia exposure in fish. Results showed that glycolysis was inhibited, and lipolysis was enhanced in ASA/H_ASA groups. The PPAR signaling pathway was activated, increasing fatty acid β-oxidation and lipophagy to mitigate energy crisis. Both ASA and H_ASA exposures induced p53 expression and inhibited the TOR pathway to combat environmental stress. However, a greater energy demand and heightened sensitivity to ASA were observed in H_ASA compared to ASA exposure. Disruptions in energy and detoxification pathways led to increased stress responses, including enhanced antioxidant activities, autophagy, and apoptotic events, as observed in organelle structures. Overall, sub-chronic H_ASA exposure caused liver injury in M. chulae by affecting energy metabolism, antioxidant regulation, and autophagy processes. This study highlights the influence of hypoxia on ASA toxicity in fish, providing valuable insights for ecological risk assessment of NSAIDs.

Acetylsalicylic acid reduces cigarette smoke withdrawal-induced anxiety in rats via modulating the expression of NFĸB, GLT-1, and xCT

Background: Chronic exposure to cigarette smoke produces neuroinflammation and long-term changes in neurotransmitter systems, especially glutamatergic systems. Objective: We examined the effects of cigarette smoke on astroglial glutamate transporters as well as NF-κB expression in mesocorticolimbic brain regions, prefrontal cortex (PFC) and nucleus accumbens (NAc). The behavioral consequences of cigarette smoke exposure were assessed using open field (OF) and light/dark (LD) tests to assess withdrawal-induced anxiety-like behavior. Methods: Sprague-Dawley rats were randomly assigned to five experimental groups: a control group exposed only to standard room air, a cigarette smoke exposed group treated with saline vehicle, two cigarette smoke exposed groups treated with acetylsalicylic acid (ASA) (15 mg/kg and 30 mg/kg, respectively), and a group treated only with ASA (30 mg/kg). Cigarette smoke exposure was performed for 2 h/day, 5 days/week, for 31 days. Behavioral tests were conducted weekly, 24 h after cigarette smoke exposure, during acute withdrawal. At the end of week 4, rats were given either saline or ASA 45 min before cigarette exposure for 11 days. Results: Cigarette smoke increased withdrawal-induced anxiety, and 30 mg/kg ASA attenuated this effect. Cigarette smoke exposure increased the relative mRNA and protein expression of nuclear factor ĸB (NFĸB) in PFC and NAc, and ASA treatment reversed this effect. Also, cigarette smoke decreased the relative mRNA and protein expression of glutamate transporter1 (GLT-1) and the cystine-glutamate transporter (xCT) in the PFC and the NAc, while ASA treatment normalized their expression. Conclusion: Cigarette smoke caused neuroinflammation, alterations in glutamate transporter expression, and increased anxiety-like behavior, and these effects were attenuated by acetylsalicylic acid treatment.

Beta-Sitosterol Modulates the Migration of Vascular Smooth Muscle Cells via the PPARG/AMPK/mTOR Pathway

INTRODUCTION

The increased migration of vascular smooth muscle cells (VSMCs) is an essential pathological factor in the early development of atherosclerosis. Beta-sitosterol (BS), a natural phytosterol abundant in plant seeds, exhibits various bioactivities, including cardioprotective effects. However, its effects on VSMC migration and underlying mechanisms remain to be explored.

METHOD AND RESULT

BS inhibited the proliferation and migration of angiotensin II-induced A7r5 cells and reduced intracellular oxidative stress. Targets related to VSMC migration and the targets of BS were screened, cross-referenced, and analyzed by network pharmacology combined with molecular docking technology. The identified targets were verified at the protein and gene levels using Western blotting and quantitative PCR, respectively. BS was observed to activate peroxisome proliferator-activated receptor-γ (PPARG) and adenosine 5'-monophosphate-activated protein kinase (AMPK) and negatively regulate mammalian target of rapamycin (mTOR) expression. Furthermore, a PPARG inhibitor reversed the BS-induced activation of AMPK and mTOR.

CONCLUSION

This study indicated that regulation of the PPARG/AMPK/mTOR signaling pathway could potentially contribute to the inhibitory effects of BS on angiotensin II-induced VSMC migration.

A dual mechanism fully blocks ethanol relapse: Role of vagal innervation

Previous studies showed that vagotomy markedly inhibits alcohol self-administration. Present studies hypothesised that vagotomy significantly adds to the inhibition of alcohol relapse induced by drugs that reduce the alcohol-induced hyperglutamatergic state (e.g., N-acetylcysteine + acetylsalicylic acid). The alcohol relapse paradigm tested gauges the elevated alcohol intake observed in animals that had consumed ethanol chronically, were subjected to a prolonged alcohol deprivation and are subsequently allowed ethanol re-access. Ethanol-drinker rats (UChB) were exposed to 10% and 20% ethanol and water concurrently for 4 months, were alcohol deprived for 14 days and were thereafter allowed re-access to the ethanol solutions. An initial binge-like drinking episode is observed upon ethanol re-access, followed by a protracted elevated ethanol intake that exceeds the predeprivation intake baseline. Prior to ethanol re-access, animals were (i) administered N-acetylcysteine (40 mg/kg/day) + acetylsalicylic acid (15 mg/kg/day), (ii) were bilaterally vagotomised, (iii) were exposed to both treatments or (iv) received no treatments. The initial binge-like relapse intake and a protracted elevated ethanol intake observed after repeated ethanol deprivations/re-access cycles were inhibited by 50%-70% by the administration of N-acetylcysteine + acetylsalicylic acid and by 40%-70% by vagotomy, while the combined vagotomy plus N-acetylcysteine + acetylsalicylic acid treatment inhibited both the initial binge-like intake and the protracted ethanol intake by >95% (p < 0.001), disclosing a dual mechanism of ethanol relapse and subsequent inhibition beyond that induced by either treatment alone. Future exploration into the mechanism by which vagal activity contributes to ethanol relapse may have translational promise.

Profiling oxylipins released from human platelets activated through the GPVI collagen receptor

In addition to haemostasis, platelets are involved in pathological processes, often driven by material released upon activation. Interaction between collagen and glycoprotein VI (GPVI) is a primary platelet stimulus that liberates arachidonic acid and linoleic acid from membrane phospholipids. These are oxidised by cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) to eicosanoids and other oxylipins with various biological properties. Using liquid chromatography-tandem mass spectrometry we found that GPVI-stimulated platelets released significant levels of ten oxylipins; the well documented TxA2 and 12-HETE, PGD₂ and PGE_2, as well as 8-, 9-, 11-, and 15-HETE, 9- and 13-HODE.¹ Levels of oxylipins released from washed platelets mirrored those from platelets stimulated in the presence of plasma, indicating generation from intracellular, rather than exogenous AA/LA. Inhibition of COX-1 with aspirin, as expected, completely abolished production of TxA₂ and PGD/E₂, but also significantly inhibited the release of 11-HETE (89 ± 3%) and 9-HODE (74 ± 6%), and reduced 15-HETE and 13-HODE by ∼33 %. Inhibition of 12-LOX by either esculetin or ML355 inhibited the release of all oxylipins apart from 15-HETE. These findings suggest routes to modify the production of bioactive molecules released by activated platelets.

Immune treatments for alcohol use disorder: A translational framework

While the immune system is essential for survival, an excessive or prolonged inflammatory response, such as that resulting from sustained heavy alcohol use, can damage the host and contribute to psychiatric disorders. A growing body of literature indicates that the immune system plays a critical role in the development and maintenance of alcohol use disorder (AUD). As such, there is enthusiasm for treatments that can restore healthy levels of inflammation as a mechanism to reduce drinking and promote recovery. In this qualitative literature review, we provide a conceptual rationale for immune therapies and discuss progress in medications development for AUD focused on the immune system as a treatment target. This review is organized into sections based on primary signaling pathways targeted by the candidate therapies, namely: (a) toll-like receptors, (b) phosphodiesterase inhibitors, (c) peroxisome proliferator-activated receptors, (d) microglia and astrocytes, (e) other immune pharmacotherapies, and (f) behavioral therapies. As relevant within each section, we examine the basic biological mechanisms of each class of therapy and evaluate preclinical research testing the role of the therapy on mitigating alcohol-related behaviors in animal models. To the extent available, translational findings are reviewed with discussion of completed and ongoing randomized clinical trials and their findings to date. An applied and clinically focused approach is taken to identify the potential clinical applications of the various treatments reviewed. We conclude by delineating the most promising candidate treatments and discussing future directions by considering opportunities for immune treatment development and personalized medicine for AUD.

Could Lipoxins Represent a New Standard in Ischemic Stroke Treatment?

Introduction: Cardiovascular diseases including stroke are one of the most common causes of death. Their main cause is atherosclerosis and chronic inflammation in the body. An ischemic stroke may occur as a result of the rupture of unstable atherosclerotic plaque. Cardiovascular diseases are associated with uncontrolled inflammation. The inflammatory reaction produces chemical mediators that stimulate the resolution of inflammation. One of these mediators is lipoxins—pro-resolving mediators that are derived from the omega-6 fatty acid family, promoting inflammation relief and supporting tissue regeneration. Aim: The aim of the study was to review the available literature on the therapeutic potential of lipoxins in the context of ischemic stroke. Material and Methods: Articles published up to 31 January 2021 were included in the review. The literature was searched on the basis of PubMed and Embase in terms of the entries: ‘stroke and lipoxin’ and ‘stroke and atherosclerosis’, resulting in over 110 articles in total. Studies that were not in full-text English, letters to the editor, and conference abstracts were excluded. Results: In animal studies, the injection/administration of lipoxin A4 improved the integrity of the blood–brain barrier (BBB), decreased the volume of damage caused by ischemic stroke, and decreased brain edema. In addition, lipoxin A4 inhibited the infiltration of neutrophils and the production of cytokines and pro-inflammatory chemokines, such as interleukin (Il-1β, Il-6, Il-8) and tumor necrosis factor-α (TNF-α). The beneficial effects were also observed after introducing the administration of lipoxin A4 analog—BML-111. BML-111 significantly reduces the size of a stroke and protects the cerebral cortex, possibly by reducing the permeability of the blood–brain barrier. Moreover, more potent than lipoxin A4, it has an anti-inflammatory effect by inhibiting the production of pro-inflammatory cytokines and increasing the amount of anti-inflammatory cytokines. Conclusions: Lipoxins and their analogues may find application in reducing damage caused by stroke and improving the prognosis of patients after ischemic stroke.

Effect of combined acetylsalicylic acid and statins treatment on intracranial aneurysm rupture

Background

Acetylsalicylic acid (ASA) and statins have been identified as potentially reducing the risk of intracranial aneurysms (IA) rupture. We aim to determine the effect of this drugs on the risk of rupture of IA.

Patients and methods

We performed a retrospective cohort study from a prospective database of patients with IA treated in our institution between January 2013 and December 2018. Demographics, previous oral treatments, presence of multiple aneurysms, size of aneurysm, lobulation, location and morphology of the aneurysms were recorded. Patients were dichotomized as ruptured and unruptured IA.

Results

A total of 408 IA were treated, of which 283 (68.6%) were in women. The median age was 53, 194 (47.5%) were ruptured IA. 38 patients (9.3%) were receiving ASA and 84 (20.6%) were receiving statins at the moment of the IA diagnosis. In the multivariable regression analysis, ASA plus statin use and multiple aneurysms were independently associated with unruptured IA (OR 5.01, 95% CI, 1.37–18.33, P = 0.015 and OR 2.72, 95% CI 1.68–4.27, P<0.001, respectively). Whereas, lobulated wall aneurysm and PComA/AComA location were inversely and independently associated with unruptured IA condition (OR 0.34, 95% CI 0.21–0.55, P<0.001 and OR 0.37, 95% CI 0.23–0.60, P<0.001, respectively). However, ASA and statins in monotherapy were not independently associated with unruptured IA condition.

Conclusions

In our study population ASA plus statins treatment is independently associated with unruptured IA. Larger and prospective studies are required to explore this potential protective effect against IA rupture.

Administration of N-acetylcysteine Plus Acetylsalicylic Acid Markedly Inhibits Nicotine Reinstatement Following Chronic Oral Nicotine Intake in Female Rats

Background

Nicotine is the major addictive component of cigarette smoke and the prime culprit of the failure to quit smoking. Common elements perpetuating the use of addictive drugs are (i) cues associated with the setting in which drug was used and (ii) relapse/reinstatement mediated by an increased glutamatergic tone (iii) associated with drug-induced neuroinflammation and oxidative stress.

Aims

The present study assessed the effect of the coadministration of the antioxidant N-acetylcysteine (NAC) plus the anti-inflammatory acetylsalicylic acid (ASA) on oral nicotine reinstatement intake following a post-deprivation re-access in female rats that had chronically and voluntarily consumed a nicotine solution orally. The nicotine-induced oxidative stress and neuroinflammation in the hippocampus and its effects on the glutamate transporters GLT-1 and XCT mRNA levels in prefrontal cortex were also analyzed.

Results

The oral coadministration of NAC (40 mg/kg/day) and ASA (15 mg/kg/day) inhibited by 85% of the oral nicotine reinstatement intake compared to control (vehicle), showing an additive effect of both drugs. Acetylsalicylic acid and N-acetylcysteine normalized hippocampal oxidative stress and blunted the hippocampal neuroinflammation observed upon oral nicotine reinstatement. Nicotine downregulated GLT-1 and xCT gene expression in the prefrontal cortex, an effect reversed by N-acetylcysteine, while acetylsalicylic acid reversed the nicotine-induced downregulation of GLT-1 gene expression. The inhibitory effect of N-acetylcysteine on chronic nicotine intake was blocked by the administration of sulfasalazine, an inhibitor of the xCT transporter.

Conclusion

Nicotine reinstatement, following post-deprivation of chronic oral nicotine intake, downregulates the mRNA levels of GLT-1 and xCT transporters, an effect reversed by the coadministration of N-acetylcysteine and acetylsalicylic acid, leading to a marked inhibition of nicotine intake. The combination of these drugs may constitute a valuable adjunct in the treatment of nicotine-dependent behaviors.

Aspirin and N-acetylcysteine co-administration markedly inhibit chronic ethanol intake and block relapse binge drinking: Role of neuroinflammation-oxidative stress self-perpetuation

Chronic alcohol intake leads to neuroinflammation and cell injury, proposed to result in alterations that perpetuate alcohol intake and cued relapse. Studies show that brain oxidative stress is consistently associated with alcohol-induced neuroinflammation, and literature implies that oxidative stress and neuroinflammation perpetuate each other. In line with a self-perpetuating mechanism, it is hypothesized that inhibition of either oxidative stress or neuroinflammation could reduce chronic alcohol intake and relapse. The present study conducted on alcohol-preferring rats shows that chronic ethanol intake was inhibited by 50% to 55% by the oral administration of low doses of either the antioxidant N-acetylcysteine (40 mg/kg/d) or the anti-inflammatory aspirin (ASA; 15 mg/kg/d), while the co-administration of both dugs led to a 70% to 75% (P < .001) inhibition of chronic alcohol intake. Following chronic alcohol intake, a prolonged alcohol deprivation, and subsequent alcohol re-access, relapse drinking resulted in blood alcohol levels of 95 to 100 mg/dL in 60 minutes, which were reduced by 60% by either N-acetylcysteine or aspirin and by 85% by the co-administration of both drugs (blood alcohol: 10 to 15 mg/dL; P < .001). Alcohol intake either on the chronic phase or following deprivation and re-access led to a 50% reduction of cortical glutamate transporter GLT-1 levels, while aspirin administration fully returned GLT-1 to normal levels. N-acetylcysteine administration did not alter GLT-1 levels, while N-acetylcysteine may activate the cystine/glutamate transport xCT, presynaptically inhibiting relapse. Overall, the study suggests that a neuroinflammation/oxidative stress self-perpetuation cycle maintains chronic alcohol intake and relapse drinking. The co-administration of anti-inflammatory and antioxidant agents may have translational value in alcohol-use disorders.

The role of inflammation and potential pharmacological therapy in intracranial aneurysms

Intracranial aneurysms remain important clinical concern. There is relatively low risk of rupture of symptomless aneurysms incidentally found in MRA or CTA performed due to other indications. Not all of the intracranial aneurysms should or can be treated with neurosurgery intervention or endovascular embolization. Clinical strategy for small, symptomless, unruptured aneurysms is still questionable. Mechanisms underlying aneurysms formation, progression and rupture are poorly understood. Inflammation is one of the factors suspected to participate in these processes. Therefore the aim of this manuscript is to present current state of knowledge about the role of inflammation in the formation and progression of intracranial aneurysms and in their rupture process. Current knowledge about possible pharmacological treatment of intracranial aneurysms will also be presented. Macrophages infiltration seems to participate in the formation of intracranial aneurysms. Inhibition of signals sent by macrophages may prevent the aneurysms formation. Inflammation present in the wall of the aneurysm seems to be also related to the aneurysm's rupture risk. However it does not seem to be the only cause of the degeneration, but it can be a possible target of drug therapy. Some preliminary studies in humans indicate the potential role of aspirin as a factor that decrease the level of inflammation and lower the risk of rupture of intracranial aneurysms. However further research including a greater number of subjects and a prospective randomized design are necessary to assess the role of aspirin in preventing strategy for small, symptomless, unruptured intracranial aneurysms.

The Role of FAK in the Secretion of MMP9 after CD147 Stimulation in Macrophages

To investigate whether focal adhesion kinase (FAK) can participate in the secretion of matrix metalloproteinase 9 (MMP9) after CD147 stimulation in THP-1 induced macrophages; thus, to explore the potential treatment perspectives for acute coronary syndrome (ACS).Phorbol-12-myristate-13-acetate (PMA) was used to induce THP-1 cells to differentiate into macrophages. To confirm the peak mRNA and protein expression of FAK and MMP9 after the stimulation of CD147, the macrophages were divided into 5 groups (0, 3, 6, 9, and 12 hours), with 0 hours group as control group. To investigate the role of FAK in the secretion of MMP9, with stimulation of CD147 for 9 hours, FAK inhibitor 14 was used to inhibit FAK Y397 phosphorylation. The mRNA and protein expressions were quantified by qRT-PCR and western blotting, respectively. (1) Relative mRNA expression of FAK and MMP9 were both significantly up-regulated (all P < 0.05) after stimulation of CD147, FAK peaked at 9 hours (3.908 ± 0.106 versus 1, P < 0.05), whereas MMP9 peaked at 6 hours (2.522 ± 0.062 versus 1, P < 0.05). (2) Relative protein expression of FAK, pFAK, and MMP9 were all significantly increased after CD147 stimulation (all P < 0.05), FAK (1.930 ± 0.024 versus 1, P < 0.05) and pFAK (1.737 ± 0.021 versus 1, P < 0.05) peaked at 9 hours, whereas MMP9 peaked at 6 hours (1.527 ± 0.033 versus 1, P < 0.05). (3) CD147 up-regulates FAK, pFAK, and MMP9 mRNA and protein expressions in a dose-dependent manner. (4) FAK inhibitor 14 significantly reduced the relative protein expression level of pFAK (0.077 ± 0.012 versus 1, P < 0.05) and MMP9 (0.133 ± 0.012) at 9 hours after CD147 stimulation.The results demonstrated that FAK Y397 phosphorylation was involved in the secretion of MMP9 after CD147 stimulation in macrophages and may play a role in the regulation of ACS.

Apo-10'-lycopenoic acid inhibits cancer cell migration and angiogenesis and induces peroxisome proliferator-activated receptor γ

SCOPE

We have previously shown that apo-10'-lycopenoic acid (ALA), a derivative of lycopene through cleavage by carotene-9',10'-oxygenase, inhibits tumor progression and metastasis in both liver and lung cancer animal models. The underlying mechanism remains unknown. We hypothesized that ALA inhibits cancer cell motility and angiogenesis by up-regulating peroxisome proliferator-activated receptor γ (PPARγ) which is involved in controlling angiogenesis, tumor progression and metastasis.

METHODS AND RESULTS

ALA treatment, in dose-dependent manner, was effective at inhibiting migration and invasion of liver and lung cancer cells (HuH7 and A549) in both Transwell and wound-healing models, as well as suppressing actin remodeling and ruffling/lamellipodia formation in HuH7 and immortalized lung BEAS-2B cells. ALA treatment resulted in suppression of angiogenesis in both tube formation and aortic ring assays and inhibition of matrix metalloproteinase-2 expression and activation in both HuH7 and A549 cells. Additionally, ALA dose-dependently increased the mRNA expression and protein levels of PPARγ in human THLE-2 liver cells.

CONCLUSION

ALA inhibits cancer cell motility and angiogenesis and induces PPARγ expression, which could be one of the potential mechanisms for ALA protecting against tumor progression.

Matrix metalloproteinase-2 of human carotid atherosclerotic plaques promotes platelet activation

Purified active matrix metalloproteinase-2 (MMP-2) is able to promote platelet aggregation. We aimed to assess the role of MMP-2 expressed in atherosclerotic plaques in the platelet-activating potential of human carotid plaques and its correlation with ischaemic events. Carotid plaques from 81 patients undergoing endarterectomy were tested for pro-MMP-2 and TIMP-2 content by zymography and ELISA. Plaque extracts were incubated with gel-filtered platelets from healthy volunteers for 2 minutes before the addition of a subthreshold concentration of thrombin receptor activating peptide-6 (TRAP-6) and aggregation was assessed. Moreover, platelet deposition on plaque extracts immobilised on plastic coverslips under high shear-rate flow conditions was measured. Forty-three plaque extracts (53%) potentiated platelet aggregation (+233 ± 26.8%), an effect prevented by three different specific MMP-2 inhibitors (inhibitor II, TIMP-2, moAb anti-MMP-2). The pro-MMP-2/TIMP-2 ratio of plaques potentiating platelet aggregation was significantly higher than that of plaques not potentiating it (3.67 ± 1.21 vs 1.01 ± 0.43, p<0.05). Moreover, the platelet aggregation-potentiating effect, the active-MMP-2 content and the active MMP-2/pro-MMP-2 ratio of plaque extracts were significantly higher in plaques from patients who developed a subsequent major cardiovascular event. In conclusion, atherosclerotic plaques exert a prothrombotic effect by potentiating platelet activation due to their content of MMP-2; an elevated MMP-2 activity in plaques is associated with a higher rate of subsequent ischaemic cerebrovascular events.

Aspirin suppresses TNF-α-induced MMP-9 expression via NF-κB and MAPK signaling pathways in RAW264.7 cells

Numerous studies have indicated that the expression of matrix metalloproteinase-9 (MMP-9) contributes to the atherosclerotic plaque hemorrhage and rupture. Aspirin, a non-steroidal anti-inflammation drug, has been known for its anti-platelet effect in the prevention of the vascular complications of atherosclerosis. The present study aimed to investigate the pharmacological effects of aspirin on tumor necrosis factor-α (TNF-α)-induced MMP-9 expression and the underlying molecular mechanisms in murine macrophage RAW264.7 cells. Western blot analysis indicated that the protein level of MMP-9 was reduced by aspirin in a dose-dependent manner. In addition, downregulation of MMP-9 mRNA and activity were detected in aspirin-treated cells using quantitative polymerase chain reaction and a gelatin zymography assay separately. It was also observed that aspirin has a suppressive effect on the activation of nuclear factor (NF)-κB and inhibits the phosphorylation of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinases 1/2, p38 and c-Jun N-terminal kinase. Furthermore, subsequent to inhibition of the MAPK pathway by specific inhibitors (PD98059, SB203580 and SP600125), the expression of MMP-9 was reduced, indicating that the inhibitory effect of aspirin on MMP-9 in TNF-α-treated RAW264.7 cells may be, at least in part, through suppression of NF-κB activation and the MAPK pathway. These findings support the notion that aspirin has therapeutic potential application in the prevention and treatment of atherosclerosis disease.

Synergetic Neuroprotective Effect of Docosahexaenoic Acid and Aspirin in SH-Y5Y by Inhibiting miR-21 and Activating RXRα and PPARα

Parkinson's disease (PD) is a serious neurodegenerative disorder that lacks effective therapeutic methods. In this research, expressions of PPARα, RXRα, and miR-21 were evaluated in PD patients and normal controls. To investigate the effects of miR-21, docosahexaenoic acid (DHA) and aspirin (ASA) on PD, as well as the relationships between them, SH-Y5Y cells were treated with DHA, ASA, or both for 24 h. The assay showed that levels of miR-21 were increased and levels of PPARα were decreased in PD patients compared with normal controls. miR-21 was negatively correlated with PPARα in PD patients. DHA and ASA could activate RXRα and PPARα, respectively. Additionally, DHA upregulated PPARα expression by inhibiting miR-21 in SH-Y5Y cells. A combination of DHA and ASA efficiently enhanced heterodimer formations of PPARα and RXRα and increased the expression of neurotrophic factors PSD-95, brain-derived neurotrophic factor (BDNF), and glial cell-derived neurotrophic factor (GDNF), while inhibiting NFκB and COX2. These findings suggest that a combination of DHA and ASA could significantly improve the expression of PSD-95, BDNF, and GDNF by promoting heterodimerization of PPARα and RXRα, thus supplying a new therapeutic method for PD.

Application of dynamic topic models to toxicogenomics data

Background

All biological processes are inherently dynamic. Biological systems evolve transiently or sustainably according to sequential time points after perturbation by environment insults, drugs and chemicals. Investigating the temporal behavior of molecular events has been an important subject to understand the underlying mechanisms governing the biological system in response to, such as, drug treatment. The intrinsic complexity of time series data requires appropriate computational algorithms for data interpretation. In this study, we propose, for the first time, the application of dynamic topic models (DTM) for analyzing time-series gene expression data.

Results

A large time-series toxicogenomics dataset was studied. It contains over 3144 microarrays of gene expression data corresponding to rat livers treated with 131 compounds (most are drugs) at two doses (control and high dose) in a repeated schedule containing four separate time points (4-, 8-, 15- and 29-day). We analyzed, with DTM, the topics (consisting of a set of genes) and their biological interpretations over these four time points. We identified hidden patterns embedded in this time-series gene expression profiles. From the topic distribution for compound-time condition, a number of drugs were successfully clustered by their shared mode-of-action such as PPARɑ agonists and COX inhibitors. The biological meaning underlying each topic was interpreted using diverse sources of information such as functional analysis of the pathways and therapeutic uses of the drugs. Additionally, we found that sample clusters produced by DTM are much more coherent in terms of functional categories when compared to traditional clustering algorithms.

Conclusions

We demonstrated that DTM, a text mining technique, can be a powerful computational approach for clustering time-series gene expression profiles with the probabilistic representation of their dynamic features along sequential time frames. The method offers an alternative way for uncovering hidden patterns embedded in time series gene expression profiles to gain enhanced understanding of dynamic behavior of gene regulation in the biological system.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1225-0) contains supplementary material, which is available to authorized users.

A novel polymer-free ciglitazone-coated vascular stent: in vivo and ex vivo analysis of stent endothelialization in a rabbit iliac artery model

AIM

Peroxisome proliferator-activated receptor-gamma (PPARg) agonists have known pleiotropic cardiovascular effects with favourable properties in vascular remodeling, and specifically in suppression of vascular smooth muscle cell proliferation. A novel vascular stent coating using the PPARg ligand ciglitazone (CCS) was investigated regarding its effects on endothelialization after 7 and 28 days.

METHODS

Microporous bare metal stents (BMS) were coated with ciglitazone by ultrasonic flux with a load of 255 μg ciglitazone/stent. SixteenNew Zealand white rabbits, fed a with high cholesterol diet, underwent stent implantation in both iliac arteries. Everolimus-eluting stents (EES) and BMS were comparators. Histology (CD 31 immunostaining, confocal and scanning electron microscopy, morphometry) was performed after 7 and 28 days and by OCT (optical coherence tomography) in vivo after 28 days.

RESULTS

Microscopy showed comparable results with near complete endothelialization in CCS and BMS (%CD31 above stent struts after 7 days: 67.92±36.35 vs. 84.48±23.86; p = 0.55; endothel % above stent struts: 77.22±27.9 vs. 83.89±27.91; p = 0.78). EES were less endothelialized with minimal fibrin deposition, not found in BMS and CCS (% CD 31 above struts after 28 days, BMS: 100.0±0.0 vs. EES: 95.9±3.57 vs. CCS: 100.0±0.0; p = 0.0292). OCT revealed no uncovered struts in all stents after 28 days.

CONCLUSIONS

Polymer-free coating with ciglitazone, a PPARg agonist is feasible and stable over time. Our data prove unimpaired endothelial coverage of a ciglitazone-coated vascular stent system by histology and OCT. Thus, this PPARg agonist coating deserves further investigation to evaluate its potency on local neointimal suppression.

Relationship of serum polyunsaturated fatty acids with cytokines in colorectal cancer

AIM: To investigate the relationship of serum levels of polyunsaturated fatty acid (PUFA) with kinds of cytokines in colorectal cancer (CRC).

METHODS: Serum samples of 100 CRC patients were collected. The concentration of total n-3 PUFA which included C18:3 n-3, C20:5 n-3, C22:5 n-3, C22:6 n-3 and the total n-6 PUFA included C18:2 n-6, C18:3 n-6, C20:3 n-6, C20:4 n-6, and C22:5 n-6 were detected on GC-2010 Plus Gas Chromatograph with a OmegawaxTM 250 column. Cytokines were detected by MagPlexTM-C microspheres. P values for the trend were estimated by creating a continuous variable using the median value within quartiles.

RESULTS: Interleukin-6 (IL-6) showed significantly positive association with the C20:4 n-6 (P for trend = 0.004). Interferon gamma (IFN-γ) showed significant positive association with the C22:5 n-3 (P for trend = 0.035). IL-8 and matrix metalloproteinase-9 (MMP-9) showed significant inverse association with the C22:6 n-3 (P for trend = 0.049, and 0.021). MMP-2 showed significant inverse association with the C20:5 n-3 (P for trend = 0.008). MMP-7 showed significantly positive association with the ratio of n-6 PUFA and n-3 PUFA (P for trend = 0.008). MMP-7 also showed significantly inverse association with the ratio of C20:4 n-6 and (n-6 PUFA + n-3 PUFA) (P for trend = 0.024). IL-10 (P for trend = 0.023) and IL-6 (P for trend = 0.036) showed significantly positive association with the ratio of C20:4 n-6 and C20:5 n-3.

CONCLUSION: Our data suggested that serum levels of PUFA is related to the inflammation of CRC, and also play different role in regulation of immune response.

Telmisartan prevents proliferation and promotes apoptosis of human ovarian cancer cells through upregulating PPARγ and downregulating MMP‑9 expression

The mortality rate of ovarian cancer is the highest of all gynecological malignancies. Telmisartan is a commonly used clinical angiotensin receptor blocker, which has antihypertensive, anti‑inflammatory and antithrombotic effects. In the present study, it was investigated whether telmisartan could exert anticancer effects on ovarian cancer cells through upregulating peroxisome proliferator‑activated receptor γ (PPARγ) and downregulating matrix metalloproteinase‑9 (MMP‑9) expression. A 3.3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was conducted to analyze the proliferation of HEY cells. A Caspase‑3 Activity Assay kit and an Annexin V‑fluorescein isothiocyanate/propidium iodide kit were used to analyze the apoptosis of HEY cells. In addition, a gelatin zymography assay and reverse trancription‑quantitative polymerase chain reaction were included to analyze the expression of PPARγ and MMP‑9 in HEY cells. The data showed that telmisartan could significantly decrease cell viability and induce the apoptosis of HEY cells in a time‑ and dose‑dependent manner. Furthermore, telmisartan could also dose‑dependently increase the expression of PPARγ and decrease the expression of MMP‑9 in HEY cells. In addition, downregulation of the expression of PPARγ by small interfering (si)RNA could reduce the effect of telmisartan on ovarian cancer cells and increase the expression of MMP‑9. In conclusion, the results indicated that telmisartan prevents proliferation and promotes apoptosis of human ovarian cancer cells by upregulating PPARγ and downregulating MMP‑9 expression.

Aspirin and P2Y12 inhibition attenuate platelet-induced ovarian cancer cell invasion

BACKGROUND

Platelet-cancer cell interactions play a key role in successful haematogenous metastasis. Disseminated malignancy is the leading cause of death among ovarian cancer patients. It is unknown why different ovarian cancers have different metastatic phenotypes. To investigate if platelet-cancer cell interactions play a role, we characterized the response of ovarian cancer cell lines to platelets both functionally and at a molecular level.

METHODS

Cell lines 59 M and SK-OV-3 were used as in vitro model systems of metastatic ovarian cancer. Platelet cloaking of each cell line was quantified by flow cytometry. Matrigel invasion chamber assays were used to assess the invasive capacity of the cell lines. The induction of an EMT was assessed by morphology analysis and by gene expression analysis of a panel of 11 EMT markers using TaqMan RT-PCR.

RESULTS

SK-OV-3 cells adhered to and activated more platelets than 59 M cells (p = 0.0333). Platelets significantly promoted the ability of only SK-OV-3 cells to invade (p ≤ 0.0001). Morphology and transcritpome analysis indicated that platelets induce an epithelial-to-mesenchymal transition phenotype in both cells lines, with a more exaggerated response in SK-OV-3 cells. Next, we investigated if antiplatelet agents could abrogate the platelet-induced aggressive phenotype in SK-OV-3 cells. Both aspirin (p ≤ 0.05) and 2-methylthioadenosine 5'-monophosphate triethylammonium salt hydrate (P2Y12 inhibitor; p ≤ 0.01) significantly decreased their invasion capacity, and effectively reverted invasion to levels comparable to SK-OV-3 cells alone.

CONCLUSION

While there is increasing evidence for the cancer-protective effect of aspirin, this study suggests P2Y12 inhibition may also play a role. Understanding these complex interactions between platelets and cancer cells could ultimately allow the establishment of therapies tailored to inhibiting metastasis, thus significantly reducing cancer morbidity.

Peroxisome Proliferator-Activated Receptor α in Lipid Metabolism and Atherosclerosis

Atherosclerosis is a chronic inflammatory disease with deposition of excessive cholesterol in the arterial intima. Peroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor that can activate or inhibit the expression of many target genes by forming a heterodimer complex with the retinoid X receptor. Activation of PPARα plays an important role in the metabolism of multiple lipids, including high-density lipoprotein, cholesterol, low-density lipoprotein, triglyceride, phospholipid, bile acids, and fatty acids. Increased PPARα activity also mitigates atherosclerosis by blocking macrophage foam cell formation, vascular inflammation, vascular smooth muscle cell proliferation and migration, plaque instability, and thrombogenicity. Clinical use of synthetic PPARα agonist fibrate improved dyslipidemia and attenuated atherosclerosis-related disease risk. This review summarizes PPARα in lipid and lipoprotein metabolism and atherosclerosis, and also highlights its potential therapeutic benefits.

Involvement of MIF in basement membrane damage in chronically UVB-exposed skin in mice

Solar ultraviolet (UV) B radiation is known to induce matrix metalloproteinases (MMPs) that degrade collagen in the basement membrane. Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that plays an essential role in the pathophysiology of skin inflammation induced by UV irradiation. This study examined the effects of MIF on basement membrane damage following chronic UVB irradiation in mice. The back skin of MIF transgenic (Tg) and wild-type (WT) mice was exposed to UVB three times a week for 10 weeks. There was a decrease in intact protein levels of type IV collagen and increased basement membrane damage in the exposed skin of the MIF Tg mice compared to that observed in the WT mice. Moreover, the skin of the MIF Tg mice exhibited higher MIF, MMP-2 and MMP-9 expression and protein levels than those observed in the WT mice. We also found that chronic UVB exposure in MIF Tg mice resulted in higher levels of neutrophil infiltration in the dermis compared with that observed in the WT mice. In vitro experiments revealed that MIF induced increases in the MMPs expression, including that of MMP-9 in keratinocytes and MMP-2 in fibroblasts. Cultured neutrophils also secreted MMP-9 stimulated by MIF. Therefore, MIF-mediated basement membrane damage occurs primarily through MMPs activation and neutrophil influx in murine skin following chronic UVB irradiation.

Matrix metalloproteinases as drug targets in preeclampsia

Preeclampsia is an important syndrome complicating pregnancy. While the pathogenesis of preeclampsia is not entirely known, poor placental perfusion leading to widespread maternal endothelial dysfunction is accepted as a major mechanism. It has been suggested that altered placental expression of matrix metalloproteinases (MMPs) may cause shallow cytotrophoblastic invasion and incomplete remodeling of the spiral arteries. MMPs are also thought to link placental ischemia to the cardiovascular alterations of preeclampsia. In fact, MMPs may promote vasoconstriction and surface receptors cleavage affecting the vasculature. Therefore, the overall goal of this review article is to provide an overview of the pathophisiology of preeclampsia, more specifically regarding the role of MMPs in the pathogenesis of preeclampsia and the potential of MMP inhibitors as therapeutic options.

Angiotensin-converting enzyme-inhibitors, statins and the risk of hemorrhage from cerebral dural arteriovenous fistulae

Leptomeningeal venous drainage and symptomatic presentation are known risk factors for cerebral dural arteriovenous fistula (dAVF) hemorrhage. An evaluation of potentially modifiable risk factors such as hypertension and medication usage has not been undertaken to our knowledge. The authors thus reviewed a cohort of 45 consecutive patients with cerebral dAVF with leptomeningeal venous drainage and compared the rate of hemorrhagic presentation for patients with and without a history of hypertension, hyperlipidemia or the usage of certain medications. Logistic regression was performed to determine the statistical significance of associations of each factor with hemorrhagic presentation. On univariate analysis, angiotensin-converting enzyme (ACE)-inhibitors (odds ratio [OR] 0.100, 95% confidence interval [CI] 0-0.764, p=0.024) and statins (OR 0.142, 95% CI 0.025-0.825, p=0.030) were associated with a statistically significant lower rate of hemorrhagic presentation. A trend toward a lower rate of hemorrhagic presentation was seen for patients taking aspirin (OR 0.153, 95% CI 0.016-1.43, p=0.10). These trends continued on multivariate analysis; however they did not meet statistical significance (p>0.05). Beta-blockers, calcium channel blockers, warfarin and selective serotonin reuptake inhibitors did not have a statistically significant association with the rate of hemorrhagic presentation (p>0.05). Although limited by small sample size, these results may suggest a beneficial effect of statins and ACE-inhibitors on the rate of dAVF hemorrhagic presentation, potentially as a result of anti-inflammatory, anti-angiogenic or even venous antithrombotic mechanisms. Despite this study's limitations, we hope it encourages further evaluation of potentially modifiable risk factors for vascular malformation hemorrhage.

The effects of PPARγ agonist rosiglitazone on neointimal hyperplasia in rabbit carotid anastomosis model

Background

Neointimal hyperplasia involving smooth muscle cell (SMC) proliferation, migration and extracellular matrix (ECM) degradation is an important component of atherosclerosis. It develops as a response to vascular injury after balloon angioplasty and vascular graft placement. Matrix metalloproteinases (MMPs) induce SMC proliferation, migration and contribute to intimal hyperplasia by degrading ECM. PPARγ agonists inhibit SMC proliferation, migration and lesion formation. In this study, we aimed to investigate the effects of PPARγ agonist rosiglitazone on neointimal hyperplasia and gelatinase (MMP-2 and MMP-9) expressions in rabbit carotid anastomosis model.

Methods

New Zealand white rabbits (n = 13, 2.7–3.2 kg) were divided into placebo and treatment groups. Right carotid artery (CA) was transected and both ends were anastomosed. Treatment group (n = 6) received rosiglitazone (3 mg/kg/day/p.o.) and placebo group (n = 7) received PBS (phosphate buffered saline, 2.5 ml/kg/day/p.o.) for 4 weeks postoperatively. After the sacrification, right and left CAs were isolated. Morphometric analyses and immunohistochemical examinations for gelatinases were performed.

Results

Intimal area (0.055 ± 0.005 control vs 0.291 ± 0.020 μm² anastomosed, p < 0,05) and index (0.117 ± 0.002 control vs 0.574 ± 0.013 anastomosed, p < 0,01) significantly increased in anastomosed arteries compared to control arteries from placebo group. However, in rosiglitazone-treated group, intimal area (0.291 ± 0.020 PBS vs 0.143 ± 0.027 rosiglitazone, p < 0,05) and index (0.574 ± 0.013 PBS vs 0.263 ± 0.0078 rosiglitazone, p < 0,01) significantly decreased. Furthermore, gelatinase immunopositivity was found to have significantly increased in anastomosed arteries from placebo group and decreased with rosiglitazone treatment.

Conclusions

These results suggest that rosiglitazone may prevent neointimal hyperplasia, which is the most important factor involved in late graft failure, by inhibiting gelatinase enzyme expression.

Matrix metalloproteinases in diabetic retinopathy: potential role of MMP-9

INTRODUCTION

Diabetic retinopathy remains one of the most feared complications of diabetes. Despite extensive research in the field, the molecular mechanism responsible for the development of this slow progressing disease remains unclear. In the pathogenesis of diabetic retinopathy, mitochondria are damaged and inflammatory mediators are elevated before the histopathology associated with the disease can be observed. Matrix metalloproteinases (MMPs) regulate a variety of cellular functions including apoptosis and angiogenesis. Diabetic environment stimulates the secretion of several MMPs that are considered to participate in complications, including retinopathy, nephropathy and cardiomyopathy. Patients with diabetic retinopathy and also animal models have shown increased MMP-9 and MMP-2 in their retina and vitreous. Recent research has shown that MMPs have dual role in the development of diabetic retinopathy; in the early stages of the disease (pre-neovascularization), MMP-2 and MMP-9 facilitate the apoptosis of retinal capillary cells, possibly via damaging the mitochondria, and in the later phase, they help in neovascularization.

AREAS COVERED

This article reviews the literature to evaluate the role of MMPs, especially MMP-9, in the development of diabetic retinopathy, and presents existing evidence that the inhibitors targeted toward MMP-9, depending on the duration of diabetes at the times their administration could have potential to prevent the progression of this blinding disease, and protect the vision loss.

EXPERT OPINION

Inhibitors of MMPs could have dual role: in the early stages of the diseases, inhibit capillary cell apoptosis, and if the disease has progressed to the angiogenic stage, inhibit the growth of new vessels.

Aspirin as a promising agent for decreasing incidence of cerebral aneurysm rupture

BACKGROUND AND PURPOSE

Chronic inflammation is postulated as an important phenomenon in intracranial aneurysm wall pathophysiology. This study was conducted to determine if aspirin use impacts the occurrence of intracranial aneurysm rupture.

METHODS

Subjects enrolled in the International Study of Unruptured Intracranial Aneurysms (ISUIA) were selected from the prospective untreated cohort (n=1691) in a nested case-control study. Cases were subjects who subsequently had a proven aneurysmal subarachnoid hemorrhage during a 5-year follow-up period. Four control subjects were matched to each case by site and size of aneurysm (58 cases, 213 control subjects). Frequency of aspirin use was determined at baseline interview. Aspirin frequency groups were analyzed for risk of aneurysmal hemorrhage. Bivariable and multivariable analyses were performed using conditional logistic regression.

RESULTS

A trend of a protective effect for risk of unruptured intracranial aneurysm rupture was observed. Patients who used aspirin 3× weekly to daily had an OR for hemorrhage of 0.40 (95% CI, 0.18-0.87); reference group, no use of aspirin), patients in the "< once a month" group had an OR of 0.80 (95% CI, 0.31-2.05), and patients in the "> once a month to 2×/week" group had an OR of 0.87 (95% CI, 0.27-2.81; P=0.025). In multivariable risk factor analyses, patients who used aspirin 3 times weekly to daily had a significantly lower odds of hemorrhage (adjusted OR, 0.27; 95% CI, 0.11-0.67; P=0.03) compared with those who never take aspirin.

CONCLUSIONS

Frequent aspirin use may confer a protective effect for risk of intracranial aneurysm rupture. Future investigation in animal models and clinical studies is needed.

A lipoxin A4 analog ameliorates blood-brain barrier dysfunction and reduces MMP-9 expression in a rat model of focal cerebral ischemia-reperfusion injury

LXA(4) methyl ester (LXA(4)ME), a lipoxin A(4) analog, reduces ischemic insult in the rat models of transient or permanent cerebral ischemic injury. We investigated whether LXA(4)ME could ameliorate blood-brain barrier (BBB) dysfunction after stroke by reducing matrix metalloproteinase (MMP)-9 expression. Adult male rats were subjected to 2-h middle cerebral artery occlusion (MCAO) followed by 24-h reperfusion. Brain infarctions were detected by triphenyltetrazolium chloride (TTC) staining. BBB dysfunction was determined by examining brain edema and Evans Blue extravasation. Temporal expression of MMP-9 was determined by zymography and Western blot. The presence of tissue inhibitors of metalloproteinase-1 (TIMP-1) was also determined by Western blot in tissue protein sample. Brain edema and Evans Blue leakage were significantly reduced after stroke in the LXA(4)ME group and were associated with reduced brain infarct volumes. MMP-9 activity and expression were inhibited by LXA(4)ME after stroke. In addition, LXA(4)ME significantly increased TIMP-1 protein levels. Our results indicate that LXA(4)ME reduces brain injury by improving BBB function in a rat model of MCAO, and that a relationship exists between BBB permeability and MMP-9 expression following ischemic insult. Furthermore, these results suggest that LXA(4)ME-mediated reduction of MMP-9 following stroke are attributed to increased TIMP-1 expression.

Mesalamine restores angiogenic balance in experimental ulcerative colitis by reducing expression of endostatin and angiostatin: novel molecular mechanism for therapeutic action of mesalamine

Mesalamine (5-aminosalicylate acid, 5-ASA) is an effective treatment for ulcerative colitis (UC). The mechanisms of its actions are not fully understood. Because angiogenesis is critical for healing UC, we examined whether 5-ASA alters the angiogenic balance between angiogenic factors [e.g., vascular endothelial growth factor (VEGF)] and antiangiogenic factors (e.g., endostatin and angiostatin) in the colon in experimental UC. Rats were treated with saline or 5-ASA (100 mg/kg) twice daily and euthanized 3 or 7 days after iodoacetamide-induced UC. Clinical signs (e.g., lethargy, diarrhea) and UC lesions were measured. Expression of VEGF, endostatin, angiostatin, tissue necrosis factor alpha (TNF-alpha), and matrix metalloproteinases (MMPs) 2 and 9 was determined by Western blots, enzyme-linked immunosorbent assay, and zymography in the distal colon. 5-ASA treatment reduced lethargy and diarrhea and significantly decreased colonic lesions (by approximately 50%) compared with saline treatment in UC (both, P < 0.05). 5-ASA did not reverse the increased levels of VEGF, but it significantly reduced expression of endostatin and angiostatin in UC compared with vehicle treatment (both, P < 0.05). Furthermore, 5-ASA treatment significantly diminished increased activity of TNF-alpha and MMP9 in UC. This is the first demonstration that 5-ASA treatment reverses an imbalance between the angiogenic factor VEGF and antiangiogenic factors endostatin and angiostatin in experimental UC. The effect of 5-ASA in UC may be caused by the down-regulation of expression of endostatin and angiostatin by modulation of MMP2 and MMP9 via inhibition of TNFalpha. The inhibition of antiangiogenic factors may represent a novel molecular mechanism of the therapeutic action of 5-ASA.