The impact of heparin compounds on cellular inflammatory responses: a construct for future investigation and pharmaceutical development

Glycosaminoglycans' Ability to Promote Wound Healing: From Native Living Macromolecules to Artificial Biomaterials

Glycosaminoglycans (GAGs) are important for the occurrence of signaling molecules and maintenance of microenvironment within the extracellular matrix (ECM) in living tissues. GAGs and GAG-based biomaterial approaches have been widely explored to promote in situ tissue regeneration and repair by regulating the wound microenvironment, accelerating re-epithelialization, and controlling ECM remodeling. However, most approaches remain unacceptable for clinical applications. To improve insights into material design and clinical translational applications, this review highlights the innate roles and bioactive mechanisms of native GAGs during in situ wound healing and presents common GAG-based biomaterials and the adaptability of application scenarios in facilitating wound healing. Furthermore, challenges before the widespread commercialization of GAG-based biomaterials are shared, to ensure that future designed and constructed GAG-based artificial biomaterials are more likely to recapitulate the unique and tissue-specific profile of native GAG expression in human tissues. This review provides a more explicit and clear selection guide for researchers designing biomimetic materials, which will resemble or exceed their natural counterparts in certain functions, thereby suiting for specific environments or therapeutic goals.

The beneficial role of Hepcidin peptide inhibitor in improved the symptoms of COVID-19 in diabetics: anti-inflammatory and potential therapeutic effects

Coronavirus Disease 2019 (COVID-19) is a recent public health issue worldwide. Also, diabetes is a frequent condition with high mortality. There is a strong relationship between COVID-19 and diabetes. This article analyses the intricate relationship between COVID-19 and hepcidin. Hepcidin increases in aged non-insulin diabetic patients. Hepcidin is the last target treatment of several medications commonly used. Viral diseases, especially SARS-CoV19, can activate the hepcidin pathway leading to an elevation in the iron load. This increased iron is released into the bloodstream and results in cell death through ferroptosis, like free iron. Excess iron has pro-coagulative and toxic effects. Hepcidin overexpression and iron overload are associated with COVID-19 infection and can be considered potential targets for treatment. Several studies have shown dalteparin (anti-Hepcidin) could improve the symptoms of COVID-19 in diabetics by appropriately modulating and decreasing oxidative stress and inflammation. This finding can be leading to enhancing the existing knowledge about Therapeutic measures for reducing Covid-19 impairments in diabetics and is suggested as a possible therapeutic agent in diabetes.

The Potential Role of Heparin in Patients With COVID-19: Beyond the Anticoagulant Effect. A Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is responsible of variable clinical manifestations, ranging from no symptoms to severe pneumonia with acute respiratory distress syndrome, septic shock, and multi-organ failure resulting in death. To date no specific antiviral drug have been approved for COVID-19, so the treatment of the disease is mainly focused on symptomatic treatment and supportive care. Moreover, there are no treatments of proven efficacy to reduce the progression of the disease from mild/moderate to severe/critical. An activation of the coagulation cascade leading to severe hypercoagulability has been detected in these patients, therefore early anticoagulation may reduce coagulopathy, microthrombus formation, and the risk of organ damages. The role of heparin in COVID-19 is supported by a lot of studies describing its pleiotropic activity but it must be proven in clinical trials. Several protocols have been designed to assess the risk-benefit profile of heparin (low-molecular-weight or unfractionated heparin) in hospitalized subjects. Although prophylactic doses may be adequate in most patients, it is important to wait the results of clinical trials in order to define the appropriate effective dose able to improve disease outcome.

Continuous infusion of low-dose unfractionated heparin after aneurysmal subarachnoid hemorrhage: a preliminary study of cognitive outcomes

OBJECTIVE

Cognitive dysfunction occurs in up to 70% of aneurysmal subarachnoid hemorrhage (aSAH) survivors. Low-dose intravenous heparin (LDIVH) infusion using the Maryland protocol was recently shown to reduce clinical vasospasm and vasospasm-related infarction. In this study, the Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive changes in aSAH patients treated with the Maryland LDIVH protocol compared with controls.

METHODS

A retrospective analysis of all patients treated for aSAH between July 2009 and April 2014 was conducted. Beginning in 2012, aSAH patients were treated with LDIVH in the postprocedural period. The MoCA was administered to all aSAH survivors prospectively during routine follow-up visits, at least 3 months after aSAH, by trained staff blinded to treatment status. Mean MoCA scores were compared between groups, and regression analyses were performed for relevant factors.

RESULTS

No significant differences in baseline characteristics were observed between groups. The mean MoCA score for the LDIVH group (n = 25) was 26.4 compared with 22.7 in controls (n = 22) (p = 0.013). Serious cognitive impairment (MoCA ≤ 20) was observed in 32% of controls compared with 0% in the LDIVH group (p = 0.008). Linear regression analysis demonstrated that only LDIVH was associated with a positive influence on MoCA scores (β = 3.68, p =0.019), whereas anterior communicating artery aneurysms and fevers were negatively associated with MoCA scores. Multivariable linear regression analysis resulted in all 3 factors maintaining significance. There were no treatment complications.

CONCLUSIONS

This preliminary study suggests that the Maryland LDIVH protocol may improve cognitive outcomes in aSAH patients. A randomized controlled trial is needed to determine the safety and potential benefit of unfractionated heparin in aSAH patients.

MMX® technology and its applications in gastrointestinal diseases

The Multimatrix^® (MMX^®) preparation MMX^® is a recently obtained drug formulation developed to facilitate release of high concentrations of active drugs into the colon, with a homogeneous distribution along all colonic segments, particularly the most distal ones; the distal colonic tracts, indeed, are the most difficult to reach in significant amounts when a drug is given orally. The MMX^® formulation is characterized by a lipophilic matrix dispersed in a hydrophilic structure. Indeed, in the last few years, MMX^® technology has been widely used in the development of various drugs for the treatment of inflammatory and infectious gastrointestinal diseases localized in the colon. In particular, MMX^® mesalamine, budesonide and parnaparin formulations have been investigated in patients with ulcerative colitis, and the first two have reached worldwide registration for the treatment of this disease. Moreover, MMX^®-rifamycin is being positively tested in the treatment of colonic bacterial infections, including traveler's diarrhea. MMX^® technology is, thus, proving to be a very effective formulation for the treatment of various colonic diseases. This effectiveness has been related not only to specific colonic delivery, but also to its ability to act in a once-daily dosage, thus favouring patients' adherence to prescribed schedules of treatment. The effective delivery of the active molecule to the site of need in the colon is also associated with very low systemic absorption and very low rates of adverse events (AEs). In this paper, we have reviewed all clinical trials performed with an MMX^®-bound drug and all possible real-life reports, in order to give an overall evaluation of MMX^®.

Assessment of Pharmacological Prophylaxis for Acute Pancreatitis Following ERCP in Patients with Choledoholithiasis

Endoscopic retrograde cholangiopancreatography (ERCP) is an effective tool in the diagnostics and treatment of bile duct diseases. Although minimally invasive, the procedure is associated with a risk of complications, with acute pancreatitis being the most serious. In recent years, high hopes have been placed on pharmacological prevention of acute pancreatitis after ERCP. The aim of the study was assessment of the efficacy of low-molecular-weight heparin and somatostatin in combination with diclofenac in the prevention of acute pancreatitis after ERCP.

MATERIAL AND METHODS

The study enrolled three groups of 30 patients diagnosed with cholelithiasis; group I: patients who received low-molecular-weight heparin prior to ERCP, group II: patients who received somatostatin and diclofenac, group III: control group. The study assessed the incidence of acute pancreatitis, hyperamylasemia and increased CRP levels.

RESULTS

Acute pancreatitis was observed in 13.3% of group I patients, 10% of group II patients and 16.7% of group III patients (no statistical significance). Hyperamylasemia was observed in 16.7% of group I patients, 16.7% of group II patients and 43.3% of group III patients. These differences were statistically significant. No significant differences were found in the occurrence of increased CRP levels among the study groups.

CONCLUSIONS

No significant reduction in the occurrence of acute pancreatitis after ERCP was observed in patients who received pharmacological prophylaxis. A significant reduction in the occurrence of hyperamylasemia was found in drug-treated patients.

Novel Treatments in Neuroprotection for Aneurysmal Subarachnoid Hemorrhage

OPINION STATEMENT

New neuroprotective treatments aimed at preventing or minimizing "delayed brain injury" are attractive areas of investigation and hold the potential to have substantial beneficial effects on aneurysmal subarachnoid hemorrhage (aSAH) survivors. The underlying mechanisms for this "delayed brain injury" are multi-factorial and not fully understood. The most ideal treatment strategies would have the potential for a pleotropic effect positively modulating multiple implicated pathophysiological mechanisms at once. My personal management (RFJ) of patients with aneurysmal subarachnoid hemorrhage closely follows those treatment recommendations contained in modern published guidelines. However, over the last 5 years, I have also utilized a novel treatment strategy, originally developed at the University of Maryland, which consists of a 14-day continuous low-dose intravenous heparin infusion (LDIVH) beginning 12 h after securing the ruptured aneurysm. In addition to its well-known anti-coagulant properties, unfractionated heparin has potent anti-inflammatory effects and through multiple mechanisms may favorably modulate the neurotoxic and neuroinflammatory processes prominent in aneurysmal subarachnoid hemorrhage. In my personal series of patients treated with LDIVH, I have found significant preservation of neurocognitive function as measured by the Montreal Cognitive Assessment (MoCA) compared to a control cohort of my patients treated without LDIVH (RFJ unpublished data presented at the 2015 AHA/ASA International Stroke Conference symposium on neuroinflammation in aSAH and in abstract format at the 2015 AANS/CNS Joint Cerebrovascular Section Annual Meeting). It is important for academic physicians involved in the management of these complex patients to continue to explore new treatment options that may be protective against the potentially devastating "delayed brain injury" following cerebral aneurysm rupture. Several of the treatment options included in this review show promise and could be carefully adopted as the level of evidence for each improves. Other proposed neuroprotective treatments like statins and magnesium sulfate were previously thought to be very promising and to varying degrees were adopted at numerous institutions based on somewhat limited human evidence. Recent clinical trials and meta-analysis have shown no benefit for these treatments, and I currently no longer utilize either treatment as prophylaxis in my practice.

Cancer-Associated Thrombosis: Regulatory Mechanisms and Emerging Directions

Venous thrombosis is a common complication in cancer patients, and some cancer chemotherapies are associated with an increased risk of venous thromboembolism. The regulatory mechanisms that control thrombus formation and subsequent resolution in patients with cancer, however, are incompletely understood, and novel treatments for cancer-associated thrombosis may arise from a better understanding of such mechanisms. In this chapter, pathways that regulate cancer-associated thrombus formation are outlined, and the effects of anti-angiogenic cancer chemotherapies on venous thrombus resolution are highlighted. Potentially pro-thrombotic effects of anti-angiogenic agents are important considerations when managing the complications of venous thrombosis in cancer patients.

Anticoagulant effects of inhaled unfractionated heparin in the dog as determined by partial thromboplastin time and factor Xa activity

OBJECTIVE

To evaluate the anticoagulant effects of inhaled heparin in dogs.

DESIGN

This study was conducted in 3 phases. In phase 1, bronchoalveolar lavage fluid (BALf) was collected to generate an in vitro calibration curve to relate heparin concentration to the activated partial thromboplastin time (aPTT). In phase 2, heparin was administered via nebulization to determine the threshold dose needed to prolong systemic aPTT. In phase 3, the local anticoagulant activity of inhaled heparin was determined by measurement of BALf anti-Xa activity and aPTT.

SETTING

University teaching hospital.

ANIMALS

Six healthy intact female Walker Hounds were used in this study. Two dogs were used for each phase.

INTERVENTIONS

Inhaled unfractionated sodium heparin was administered in doses ranging from 50,000 to 200,000 IU.

RESULTS

In vitro addition of heparin to BALf caused a prolongation in aPTT. Inhaled heparin at doses as high as 200,000 IU failed to prolong systemic aPTT, and a threshold dose could not be determined. No significant local anticoagulant effects were detected.

CONCLUSIONS

Even at doses higher than those known to be effective in people, inhaled heparin appears to have no detectable local or systemic anticoagulant effects in dogs with the current delivery method.

Treatment with sulphated galactan inhibits macrophage chemotaxis and reduces intraplaque macrophage content in atherosclerotic mice

Experimental data from animal models and clinical studies support connections between the haemostasis and inflammation in atherogenesis. These interfaces among inflammation and thrombogenesis have been suggested as targets for pharmacological intervention to reduce disease progression. We hypothesize that the recently discovered antithrombotic drug Sulphated Galactan (SG) (isolated from the red marine alga Acanthophora muscoides) might reduce atherosclerotic plaque vulnerability and inflammatory gene expression in 10-week aged apolipoprotein E deficient (ApoE-/-) mice under high-cholesterol diet for additional 11weeks. Then, the underlying cellular mechanisms were investigated in vitro. SG (10mg/kg) or Vehicle was subcutaneously injected from week 6 until week 11 of the diet. Treatment with SG reduced intraplaque macrophage and Tissue Factor (TF) content as compared to Vehicle-treated animals. Intraplaque TF co-localized and positively correlated with macrophage rich-areas. No changes on atherosclerotic plaque size, and other intraplaque features of vulnerability (such as lipid, neutrophil, MMP-9 and collagen contents) were observed. Moreover, mRNA expression of MMPs, chemokines and genetic markers of Th1/2/reg/17 lymphocyte polarization within mouse aortic arches and spleens was not affected by SG treatment. In vitro, treatment with SG dose-dependently reduced macrophage chemotaxis without affecting TF production. Overall, the chronic SG treatment was well tolerated. In conclusion, our results indicate that SG treatment reduced intraplaque macrophage content (by impacting on cell recruitment) and, concomitantly, intraplaque TF content of potential macrophage origin in atherosclerotic mice.

The role of hepcidin in chronic mild stress-induced depression

Depression is one of the most prevalent challenges of mental conditions. Yet its exact etiology has not been clear. Chronic stress increases the production of cytokines, which can lead to depression. Hepcidin, an iron modulator, is involved in the inflammation process as well as iron homeostasis. This study was designed to investigate the role of hepcidin, on stress-induced depression. 60 male wistar rats were entered the experiment. We used a chronic unpredictable mild stress (for 28 days) as a rat model of depression. In stressed group, three subgroups were treated with three different doses of dalteparin (a hepcidin inhibitor): 70IU/kg, 100IU/kg and 140IU/kg daily, for 4 weeks. The animals in the stressed group had more depressive-like behavior than the control group. Moreover, chronic mild stress produced an increased serum interleukin-6 levels. These effects were accompanied by an obvious increase in hepcidin mRNA level and iron content in the hippocampus. These changes were blocked by the injection of dalteparin. In conclusion, inhibition of hepcidin may reduce many pathological changes seen in stress-induced depressive disorders.

Effects of enoxaparin on myeloperoxidase release during hemodialysis

Myeloperoxidase (MPO) is a proteolytic and prooxidant enzyme largely assembled with the vascular wall, and a heparin-binding protein. We studied if low-molecular-weight heparin enoxaparin administered for hemodialysis (HD) anticoagulation causes systemic MPO activation. Plasma MPO levels were measured in patients undergoing maintenance HD with an intravenous bolus of enoxaparin. Patients were retested during HD employing dialyzers with heparin-grafted polyacrylonitrile membrane and no systemic enoxaparin administration. During enoxaparin-anticoagulated HD plasma MPO levels strikingly increased in all patients (8.6-fold at 10 minutes and 3.3-fold at 120 minutes, both P < 0.0001). The increments were directly associated with the enoxaparin dosage and strongly inversely with the predialysis levels of the enzyme. The increase in plasma MPO during systemic heparin-free HD was significantly less pronounced. Enoxaparin administered for HD anticoagulation induces a marked and dose-dependent increase in plasma MPO as a plausibly favorable result of the liberation of the enzyme from the vascular wall.

Ascidian (chordate-tunicate) and mammalian heparin enemas attenuate experimental diversion colitis

AIM

We sought to investigate whether mammalian or ascidian Styela plicata heparin enemas could diminish inflammation in experimental diversion colitis.

METHODS

Wistar-specific pathogen-free rats were submitted to a Hartmann's end colostomy and treated with enemas containing mammalian or Styela plicata heparin, or saline. Enemas were administered 3 times a week in the excluded colon segment from 4 to 8 weeks after operation. The effect of treatment was evaluated using video-endoscopic and histologic scores, measuring the cytokines interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and transforming growth factor-β production in organ cultures by enzyme-linked immunosorbent assay, quantifying T cells and macrophages, and investigating nuclear factor-kappa B (NF-κB) and external mitogen-activated protein kinase (pERK) activation.

RESULTS

Treatment with either mammalian or Styela plicata heparins decreased colonoscopic and histologic scores (P < .02) and restored the densities of collagen fibers and the number of goblet cells (P < .03) in the diverted colon. Both heparin treatments decreased the accumulation of T cells and macrophages (P < .03), and the activation of NF-κB and pERK (P < .04) in the diverted colon. The high levels of cytokines IL-1β, TNF-α, and IL-6 from the diversion colitis explants decreased (P < .05) to near normal values with heparin treatments.

CONCLUSION

The improvement of experimental diversion colitis with heparin treatments indicates the anti-inflammatory effect of these compounds, even after topical administration. Further studies with the nonhemorrhagic heparin obtained from the invertebrate Styela plicata will be necessary to confirm its efficacy for the treatment of human diversion colitis and possibly other forms of colitis.

Low-dose intravenous heparin infusion in patients with aneurysmal subarachnoid hemorrhage: a preliminary assessment

OBJECT

Aneurysmal subarachnoid hemorrhage (aSAH) predisposes to delayed neurological deficits, including stroke and cognitive and neuropsychological abnormalities. Heparin is a pleiotropic drug that antagonizes many of the pathophysiological mechanisms implicated in secondary brain injury after aSAH.

METHODS

The authors performed a retrospective analysis in 86 consecutive patients with Fisher Grade 3 aSAH due to rupture of a supratentorial aneurysm who presented within 36 hours and were treated by surgical clipping within 48 hours of their ictus. Forty-three patients were managed postoperatively with a low-dose intravenous heparin infusion (Maryland low-dose intravenous heparin infusion protocol: 8 U/kg/hr progressing over 36 hours to 10 U/kg/hr) beginning 12 hours after surgery and continuing until Day 14 after the ictus. Forty-three control patients received conventional subcutaneous heparin twice daily as deep vein thrombosis prophylaxis.

RESULTS

Patients in the 2 groups were balanced in terms of baseline characteristics. In the heparin group, activated partial thromboplastin times were normal to mildly elevated; no clinically significant hemorrhages or instances of heparin-induced thrombocytopenia or deep vein thrombosis were encountered. In the control group, the incidence of clinical vasospasm requiring rescue therapy (induced hypertension, selective intraarterial verapamil, and angioplasty) was 20 (47%) of 43 patients, and 9 (21%) of 43 patients experienced a delayed infarct on CT scanning. In the heparin group, the incidence of clinical vasospasm requiring rescue therapy was 9% (4 of 43, p = 0.0002), and no patient suffered a delayed infarct (p = 0.003).

CONCLUSIONS

In patients with Fisher Grade 3 aSAH whose aneurysm is secured, postprocedure use of a low-dose intravenous heparin infusion may be safe and beneficial.

Nadroparin sodium activates Nrf2/HO-1 pathway in acetic acid-induced colitis in rats

Effects of nadroparin sodium, a low molecular weight heparin, in colitis was investigated by analyzing proteins implicated in nuclear factor E2-related factor-2/heme oxygenase-1 (Nrf2/HO-1) and nuclear factor kappa B (NF-κB) pathways. Twenty-eight rats were used. Colitis was induced by acetic acid (AA). Nadroparin sodium was given to prevention and treatment groups in addition to AA. Colitis was assessed histologically and levels of proteins were analyzed with Western blot. Nadroparin not only prevented and ameliorated the AA-induced colitis histopathologically but also decreased expression of colon NF-κB, activator protein-1, cyclooxygenase-2, tumor necrosis factor-alpha, and IL-6, which were significantly increased in group AA compared to control. The accumulation of Nrf2 in nuclear fraction and HO-1 found low in group AA was increased with nadroparin (p < 0.05). The mean malondialdehyde level increased with AA and was decreased significantly with nadroparin prevention and treatment (p < 0.001). Nadroparin sodium has both protective and therapeutic effects against colonic inflammation via exerting anti-oxidative and anti-inflammatory effects by modulating Nrf2/HO-1 and NF-κB pathways.

Heparin reduces neuroinflammation and transsynaptic neuronal apoptosis in a model of subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) can lead to disabling motor, cognitive, and neuropsychological abnormalities. Part of the secondary injury to cerebral tissues associated with SAH is attributable to the neuroinflammatory response induced by blood. Heparin is a pleiotropic compound that reduces inflammatory responses in conditions outside the central nervous system. Using a model of SAH devoid of global insult, we evaluated the effect of delayed intravenous (IV) infusion of heparin, at a dose that does not produce therapeutic anticoagulation, on neuroinflammation, myelin preservation, and apoptosis. Adult male rats underwent bilateral stereotactic injections of autologous blood (50 μL) into the subarachnoid space of the entorhinal cortex. The rats were implanted with mini-osmotic pumps that delivered either vehicle or unfractionated heparin (10 U/kg/h IV) beginning 12 h after SAH. No mechanical or hemorrhagic injury was observed in the hippocampus. In vehicle controls assessed at 48 h, SAH was associated with robust neuroinflammation in the adjacent cortex [neutrophils, activated phagocytic microglia, nuclear factor-kappa B, tumor necrosis factor-alpha, and interleukin-1beta] and neurodegeneration (Fluoro-Jade C staining and loss of NeuN). In the hippocampus, a muted neuroinflammatory response was indicated by Iba1-positive, ED1-negative microglia exhibiting an activated morphology. The perforant pathway showed Fluoro-Jade C staining and demyelination, and granule cells of the dentate gyrus had pyknotic nuclei, labeled with Fluoro-Jade C and showed upregulation of cleaved caspase-3, consistent with transsynaptic apoptosis. Administration of heparin significantly reduced neuroinflammation, demyelination, and transsynaptic apoptosis. We conclude that delayed IV infusion of low-dose unfractionated heparin may attenuate adverse neuroinflammatory effects of SAH.

Unfractionated heparin: multitargeted therapy for delayed neurological deficits induced by subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is associated with numerous "delayed neurological deficits" (DNDs) that have been attributed to multiple pathophysiological mechanisms, including ischemia, microthrombosis, free radical damage, inflammation, and vascular remodeling. To date, effective prophylactic therapy for SAH-induced DNDs has been elusive, due perhaps to the multiplicity of mechanisms involved that render typical, single-agent therapy seemingly futile. We hypothesized that heparin, which has multiple underappreciated salutary effects, might be useful as a multitargeted prophylactic agent against SAH-induced DNDs. We performed a comprehensive review of the literature to evaluate the potential utility of heparin in targeting the multiple pathophysiological mechanisms that have been identified as contributing to SAH-induced DNDs. Our literature review revealed that unfractionated heparin can potentially antagonize essentially all of the pathophysiological mechanisms known to be activated following SAH. Heparin binds >100 proteins, including plasma proteins, proteins released from platelets, cytokines, and chemokines. Also, heparin complexes with oxyhemoglobin, blocks the activity of free radicals including reactive oxygen species, antagonizes endothelin-mediated vasoconstriction, smooth muscle depolarization, and inflammatory, growth and fibrogenic responses. Our review suggests that the use of prophylactic heparin following SAH may warrant formal study.

Haemostatic system in inflammatory bowel diseases: New players in gut inflammation

Inflammation and coagulation constantly influence each other and are constantly in balance. Emerging evidence supports this statement in acute inflammatory diseases, such as sepsis, but it also seems to be very important in chronic inflammatory settings, such as inflammatory bowel disease (IBD). Patients with Crohn’s disease and ulcerative colitis have an increased risk of thromboembolic events, and several abnormalities concerning coagulation components occur in the endothelial cells of intestinal vessels, where most severe inflammatory abnormalities occur. The aims of this review are to update and classify the type of coagulation system abnormalities in IBD, and analyze the strict and delicate balance between coagulation and inflammation at the mucosal level. Recent studies on possible therapeutic applications arising from investigations on coagulation abnormalities associated with IBD pathogenesis will also be briefly presented and critically reviewed.

Long-term anticoagulation in Kawasaki disease: Initial use of low molecular weight heparin is a viable option for patients with severe coronary artery abnormalities

Patients with severe coronary artery involvement after Kawasaki disease (KD) require long-term systemic anticoagulation. We sought to compare our experience with thrombotic coronary artery occlusions, safety profile, and degree of coronary artery aneurysm regression in KD patients treated with low molecular weight heparin (LMWH) versus warfarin. Medical records of all KD patients diagnosed between January 1990 and April 2007 were reviewed. Of 1374 KD patients, 38 (3%) received systemic anticoagulation, 25 patients received LMWH from diagnosis onward, 12 of whom were subsequently switched to warfarin, and 13 received warfarin from onset. The frequency of thrombotic coronary artery occlusions was similar between drugs. Severe bleeding was more frequent in patients on warfarin, but minor bleeding was more frequent for patients on LMWH. Patients on warfarin were at greater risk of underanticoagulation or overanticoagulation (defined as achieving an anti-activated factor X level or an international normalized ratio below or above target level) than patients on LMWH (P < 0.05). Maximum coronary artery aneurysm z-scores diminished with time for patients on LMWH (P = 0.03) but not for those on warfarin (P = 0.55). This study suggests that LMWH is a potentially viable alternative for patients, especially young ones, with severe coronary artery involvement after KD.

Colonic treatments and targets: issues and opportunities

The colon provides a plethora of therapeutic opportunities. There are multiple disease targets, drug molecules, and colon-specific delivery systems to be explored. Clinical studies highlight the potential for systemic delivery via the colon, and the emerging data on the levels of cell membrane transporters and metabolic enzymes along the gut could prove advantageous for this. Often efflux transporters and metabolic enzyme levels are lower in the colon, suggesting a potential for improved bioavailability of drug substrates at this site. The locoregional distribution of multiple metabolic enzymes (including cytochromes), efflux transporters (including P-glycoprotein and breast cancer resistance proteins), and influx transporters (including the solute carrier family) along the intestine is summarized. Local delivery to the colonic mucosa remains a valuable therapeutic option. New therapies that target inflammatory mediators could improve the treatment of inflammatory bowel disease, and old and new anticancer molecules could, when delivered topically, prove to be beneficial adjuncts to the current systemic or surgical treatments. New issues such as pharmacogenomics, chronotherapeutics, and the delivery of prebiotics and probiotics are also discussed in this review. Targeting drugs to the colon utilizes various strategies, each with their advantages and flaws. The most promising systems are considered in the light of the physiological data which influence their in vivo behavior.

Unfractionated heparin and new heparin analogues from ascidians (chordate-tunicate) ameliorate colitis in rats

The anti-inflammatory effect of mammalian heparin analogues, named dermatan sulfate and heparin, isolated from the ascidian Styela plicata was accessed in a TNBS-induced colitis model in rats. Subcutaneous administration of the invertebrate compounds during a 7-day period drastically reduced inflammation as observed by the normalization of the macroscopic and histological characteristics of the colon. At the molecular level, a decrease in the production of TNF-alpha, TGF-beta, and VEGF was observed, as well as a reduction of NF-kappaB and MAPK kinase activation. At the cellular level, the heparin analogues attenuated lymphocyte and macrophage recruitment and epithelial cell apoptosis. A drastic reduction in collagen-mediated fibrosis was also observed. No hemorrhagic events were observed after glycan treatment. These results strongly indicate the potential therapeutic use of these compounds for the treatment of colonic inflammation with a lower risk of hemorrhage when compared with mammalian heparin.

Topical heparin: a promising agent for the prevention of tracheal stenosis in airway surgery

BACKGROUND

The protective effects of topical mitomycin-C (MMC) have been well documented for tracheal stenosis; however, to the best of our knowledge, the use of heparin as an anti-inflammatory agent to support wound healing in upper airway surgery was not studied before. The aim of this study was to investigate the efficacy of topical heparin for healing of tracheal re-implants in a rabbit's model and its resultant histological changes compared with that of MMC.

METHODS

In a rabbit model (n = 21), an elliptically shaped portion of the anterior tracheal wall was excised (3-4 tracheal cartilages) under anesthesia and immersed in an isotonic saline solution containing 0.4 mg/mL (0.04%) MMC (n = 7), heparin (liquemine) 5000 U/mL (n = 7), or none (n = 7) for 2 min and then re-implanted. The follow-up period was 2 wk for all animals and then both the larynx and the trachea were excised for histological evaluation. Hematoxylin-eosin (H and E) staining was applied to the excised tissues for microscopic evaluation.

RESULTS

Compared with controls, the granulation tissue formation score in MMC group (P = 0.03), and epithelial regeneration and inflammation scores in heparin group (P = 0.032 and P = 0.022, respectively) were more favorable. The fibrosis index and tracheal lumen ratio values were also more favorable in both MMC (P = 0.019 and P = 0.0028, respectively) and heparin (P = 0.023 and P = 0.0021, respectively) groups compared with controls on the 15th d.

CONCLUSIONS

Topical heparin application may have favorable effects on healing of tracheal autografts in a rabbit model. We suggest that heparin therapy should be further researched for the prevention of tracheal stenosis in airway surgery.

Effect of Sulodexide on Plasma Transforming Growth Factor-β1 in Healthy Volunteers

It is unknown whether the glycosaminoglycan drug sulodexide interferes with transforming growth factorβ1—a member of heparin-binding family and a potent regulator of human biology and diseases. Hence, a 2-week pilot study was performed in 11 healthy men. Sulodexide was initially administered intravenously in a single dose, then—orally for 12 days and—again intravenously on study completion. Initial injection had no effect on activated form of the growth factor measured in plasma after 10 and 120 min; no change was also observed after 120 min from drug ingestion on day 7. On final intravenous administration, the growth factor levels increased by almost 60% after 10 min and remained elevated; the 120-min levels directly correlated with sulodexide dosage. Baseline cytokine levels decreased during the 2-week trial by more than 50%. In conclusion, transforming growth factor-β1 release and likely downregulation of its expression may constitute novel pharmacological effects of sulodexide.

Efficacy of intracolonic administration of low-molecular-weight heparin CB-01-05, compared to other low-molecular-weight heparins and unfractionated heparin, in experimentally induced colitis in rat

PURPOSE

Parenteral administration of low-molecular-weight heparins (LMWHs) and unfractionated heparin (UFH) resulted effective in improving the symptoms of experimental colitis in rat. Today, there is little information about their activity by intracolonic instillation. The scope of this study was to evaluate the ability of CB-01-05 (a LMWH with a mean molecular weight of about 5,700), compared to a series of other LMWHs and to UFH, directly instilled into the distal colon of the rat, to ameliorate dinitrobenzene (DNB)-induced experimental colitis.

METHOD

Adult male Wistar rats underwent colitis induction by intracolonic instillation of DNB. Starting 24 h after colitis induction, CB-01-05 (0.005-0.9 mg), other LMWHs (0.3-0.6 mg), and UFH (0.6 mg) were instilled, by rectal route, into the distal colon once a day for three consecutive days. On the day following the last administration, the animals were sacrificed and the distal colon was isolated, weighed, macroscopically examined, and processed for histology. Additional experiments in rat splenocytes, performed in order to elucidate the anti-inflammatory mechanisms of CB-01-05, were performed.

RESULTS

Among the tested items, only CB-01-05 at doses ranging from 0.2 to 0.9 mg was significantly effective in reducing colon weight increase and in improving both the mucosal damaged area and the histological score. The other LMWHs resulted far less effective, showing decreasing activity closely related with the decrease of their molecular weight, thus demonstrating their biological nonequivalence. CB-01-05 resulted also more active than UFH. CB-01-05 was shown to interfere with cytokines production by rat splenocytes, mainly inhibiting interferon (IFN)-gamma expression.

CONCLUSIONS

CB-01-05 instilled into the colon is well tolerated, has strong anti-inflammatory effect on DNB-induced colitis in rat, and is the most effective agent among other LMWHs and UFH. These results suggest that the anti-inflammatory activity of CB-01-05, together with its topical administration, could represent a new approach in the management of ulcerative colitis.

Heparin Attenuates the Expression of TNFalpha-induced Cerebral Endothelial Cell Adhesion Molecule

Heparin is a well-known anticoagulant widely used in various clinical settings. Interestingly, recent studies have indicated that heparin also has anti-inflammatory effects on neuroinflammation-related diseases, such as Alzheimer's disease and meningitis. However, the underlying mechanism of its actions remains unclear. In the present study, we examined the anti-inflammatory mechanism of heparin in cultured cerebral endothelial cells (CECs), and found that heparin inhibited the tumor necrosis factor alpha(TNFalpha)-induced and nuclear factor kappa B (NF-kappaB)-dependent expression of adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), which are crucial for inflammatory responses. Heparin selectively interfered with NF-kappaB DNA-binding activity in the nucleus, which is stimulated by TNFalpha. In addition, non-anticoagulant 2,3-O desulfated heparin (ODS) prevented NF-kappaB activation by TNFalpha, suggesting that the anti-inflammatory mechanism of heparin action in CECs lies in heparin's ability to inhibit the expression of cell adhesion molecules, as opposed to its anticoagulant actions.

Oral, colonic-release low-molecular-weight heparin: an initial open study of Parnaparin-MMX for the treatment of mild-to-moderate left-sided ulcerative colitis

BACKGROUND

Efficacy of heparin and low-molecular-weight heparins (LMWHs) in inflammatory bowel disease (IBD) treatment has been suggested. The multimatrix oral formulation MMX releases active drugs in the colon, avoiding systemic absorption. Parnaparin sodium is the LMWH chosen to be carried in the MMX formulation.

AIM

To assess the safety of three different oral dosages (70, 140 and 210 mg once daily) of Parnaparin-MMX (CB-01-05) in left-sided ulcerative colitis (UC).

METHODS

Left-sided UC patients, with a mild-to-moderate relapse were enrolled. All patients received Parnaparin-MMX for 8 weeks. Clinical Activity Index (CAI), Disease Activity Index (DAI), Endoscopic Activity Index and IBD-QoL were assessed throughout the study. A strict clinical and laboratory follow-up, including assessment of anti-factor Xa activity, was performed. Clinical remission was defined as CAI <4.

RESULTS

Ten UC patients were enrolled. One patient retired for clinical deterioration. No relevant side effects, including either interference with haemostasis parameters or increased bleeding, were observed. At the end of the treatment, seven patients (70%) were in clinical remission, only one achieving endoscopic healing. Mean final CAI, DAI and IBD-QoL scores were significantly improved from baseline.

CONCLUSIONS

Parnaparin-MMX appears to be a safe treatment option in mild-to-moderate UC. Controlled studies are warranted.

The anti-inflammatory effects of heparin and related compounds

Heparin is a glycosaminoglycan well known for its anticoagulant properties. In addition, heparin possesses anti-inflammatory effects. Although the mechanisms responsible for the anticoagulant effects of heparin are well understood, those underlying its anti-inflammatory effects are not. This review presents some of the evidence from clinical and animal studies supporting an anti-inflammatory role for heparin and heparin-related derivatives. Potential mechanisms by which heparin can exert its anti-inflammatory effects are discussed. The clinical use of heparin as an anti-inflammatory agent has been held back by the fear of bleeding. Development of nonanticoagulant heparins or heparin derivatives should mitigate this concern.

Trousseau's syndrome: multiple definitions and multiple mechanisms

In 1865, Armand Trousseau noted that unexpected or migratory thrombophlebitis could be a forewarning of an occult visceral malignancy. An analysis by Sack and colleagues in 1977 extended the term Trousseau's syndrome to include chronic disseminated intravascular coagulopathy associated with microangiopathy, verrucous endocarditis, and arterial emboli in patients with cancer, often occurring with mucin-positive carcinomas. In recent times the term has been ascribed to various clinical situations, ranging all the way from these classic descriptions to any kind of coagulopathy occurring in the setting of any kind of malignancy. These multiple definitions of Trousseau's syndrome are partly the consequence of multiple pathophysiologic mechanisms that apparently contribute to the hypercoagulability associated with cancer. Even the classic syndrome probably represents a spectrum of disorders, ranging from exaggerated fluid-phased thrombosis dependent on prothrombotic agents such as tissue factor to a platelet- and endotheliumum-based selectin-dependent microangiopathy associated with mucin-producing carcinomas, along with thrombin and fibrin production. Also considered here are recent hypotheses about genetic pathways within tumor cells that might trigger these thrombotic phenomena, and the reasons why therapy with heparins of various kinds remain the preferred treatment, probably because of their salutary actions on several of the proposed pathologic mechanisms.

Alterations in cytoskeletal and immune function-related proteome profiles in whole rat lung following intratracheal instillation of heparin

Background

Heparin has been shown to modify fundamental biologic processes ranging from blood coagulation and cell proliferation to fibrogenesis and asthma. The goal of this study was to identify specific or broad biologic responses of the rat lung to intratracheal instillation of heparin by targeted proteomic analysis.

Methods

Rats were given either aerosolized 500 μg heparin in 250 μl saline or saline alone. Lungs were harvested at 0, 24, or 96 hours post-treatment and isolated proteins analyzed by two-dimensional gel electrophoresis. Proteins which increased and decreased significantly in treated groups above controls were then selected for identification by mass spectrometry.

Results

Although heparin treatments resulted in a general reduction in cytosolic protein expression, there were significant increases within members of discrete groups of proteins. At 24 hours, proteins which function in cytoskeletal organization and in calcium signaling were up-regulated between 2- and 27-fold above baseline and untreated controls. Increased proteins include annexins V and VI, septin 2, capping G protein, actin-related protein 3, moesin, RhoGDP dissociation inhibitor, and calcyclin. A group of proteins relating to immune response and tumor suppressor function were either up-regulated (tumor suppressor p30/hyaluronic acid binding protein-1, Parkinson disease protein 7, proteosome 28 subunit/interferon-γ inducible protein, and proteosome subunit macropain α-1) or strongly down-regulated (transgelin). At 96 hours, most proteins that had increased at 24 hours remained elevated but to a much lesser degree.

Conclusion

These cumulative observations demonstrate that whole lung heparin treatment results in significant up-regulation of selected groups of proteins, primarily those related to cytoskeletal reorganization and immune function, which may prove to be relevant biomarkers useful in analysis of lung exposures/treatments as well as in system biology studies.

Sulodexide induces hepatocyte growth factor release in humans

Heparin influences numerous pleiotropic growth factors, including hepatocyte growth factor (HGF), partially by their release from endothelial and extracellular matrix stores. The effects of sulodexide, a heparin-like glycosaminoglycan medication of growing importance in medicine, on HGF liberation are not known. We performed a 2-week open-label sulodexide trial in healthy male volunteers. The drug was initially administered intravenously (i.v.) in a single dose of 1200 Lipoprotein Lipase Releasing Units (LRU), then -- orally for 12 days (500 LRU twice a day), and -- again by i.v. route (1200 LRU) on day 14. Intravenous sulodexide injections were repeatedly found to induce marked and reproducible increases in immunoreactive plasma HGF levels (more than 3500% vs baseline after 10 min, and more than 1200% after 120 min), and remained unchanged when measured 120 min following oral sulodexide administration. The percentage increments in plasma HGF evoked by i.v. sulodexide at both time points and on both days inversely correlated with baseline levels of the growth factor. On day 14, the HGF levels after 120 min and their percentage increase vs baseline were strongly and directly dependent on i.v. sulodexide dose per kg of body weight. This study shows that sulodexide has a novel, remarkable and plausibly biologically important stimulating effect on the release of pleiotropic hepatocyte growth factor in humans.

Stimulation of Hepatocyte Growth Factor Production by Heparin-derived Oligosaccharides

We previously reported that heparin post-transcriptionally stimulates the production of hepatocyte growth factor (HGF). In this study, we addressed the size-dependency of heparin fragments on the HGF-inducing activity aiming to obtain fragments without antiblood coagulant activity. Heparin fragments, produced by digestion with heparinase, were size-fractionated and tested for HGF-inducing activity in cultured human fibroblasts. The HGF-inducing activity deceased with the reduction in oligosaccharide size. Decasaccharides exerted an activity comparable with undigested heparin, while smaller oligosaccharides showed lesser activities. The anticoagulant activity of heparin fragments also decreased with size and anticoagulant activity of decasaccharides was <13% that of undigested heparin. Further fractionation of decasaccharides by anion-exchange chromatography revealed that most of the decasaccharides had HGF-inducing activity and the extent of sulfation was roughly related to the activity. The lack of N-sulfation in heparin markedly reduced HGF-inducing activity, whereas 2-O-desulfation or 6-O-desulation had a lesser influence. Moreover, an N-sulfated disaccharide showed significant HGF-inducing activity, suggesting the involvement of N-sulfation in HGF-inducing activity. Because of the much reduced anticoagulant activity, potential applications of heparin-derived oligosaccharides such as decasaccharides is considerable as a therapeutic agent for many diseases.

Neuroprotective effect of pentosan polysulphate on ischemia-related neuronal death of the hippocampus

Pentosan polysulphate (PPS) negatively charged sulphated glycosaminoglycan was studied in ischemia-related hippocampal neuronal death and compared with a low molecular weight of heparin, named dalteparin in rats. Transient global ischemia was produced by four vessel-occlusion, the occlusion of the bilateral common carotid arteries following the electrocautherization of the vertebral arteries. 3mg/kg of PPS or 300IU/kg of dalteparin was administered i.v. immediately after 7min-occlusion/reperfusion. Seven days after the operation, the animals were perfused with 4% paraformaldehyde, and paraffinized coronal brain sections measuring 6microm in thickness were stained with hematoxylin and eosin. Neuronal damage was then estimated as a ratio of the number of degenerated neurons to that of both the surviving and degenerated neurons in three distinct area of the CA1 subfield. The ratio of neuronal death increased with the length of the occlusion-time, at 5, 7 and 10min. Both PPS and dalteparin significantly inhibited the neuronal damage induced by 7min-occlusion. These results demonstrated that both PPS and dalteparin could thus protect brain neurons against ischemia/reperfusion-induced damage thus suggesting that they may be potentially useful therapeutic agents for acute ischemic stroke.

The influence of various structural parameters of semisynthetic sulfated polysaccharides on the P-selectin inhibitory capacity

Selectin-mediated leukocyte rolling along the endothelium is of key importance for maintaining the cellular immune response. The anti-inflammatory activities of heparin have partly been related to inhibition of P-selectin binding. Heparin, however, suffers from its heterogeneous variable structure, the animal origin and multiple in vivo effects. As P-selectin is a promising target for anti-inflammatory approaches, we focused on P-selectin inhibition by other sulfated polysaccharides and compared them with six heparins. We examined 15 structurally defined semisynthetic sulfated glucans, non-animal-derived from the linear glucans phycarin, curdlan or pullulan. The derivatives gradually differ in their degree of sulfation, molecular weight, and glycosidic linkage. The inhibitory capacity was analysed in a parallel plate flow chamber, detecting the rolling of U937 cells on P-selectin layers. Unfractionated heparins displayed variabilities between different preparations. Considering fractionated heparins, exceeding of a minimal mass is essential for activity. Comparing the glucan sulfates, charge density is the most important parameter for P-selectin binding. Highly sulfated derivatives are excellent inhibitors, the reduced cell binding up to 16.2+/-6.4% strongly exceeded the heparin activities. Molecular weight is of minor effects, while glycosidic backbone linkage holds certain importance. To check the P-selectin inhibition in vivo, heparin and one phycarin sulfate were tested using intravital microscopy of microvasculature in mice. Both compounds significantly reduced the rolling fractions of activated platelets on endothelium as effective as a blocking P-selectin antibody. Our study indicates that semisynthetic glucan sulfates with optimal structures block P-selectin excellently and might become promising candidates for anti-inflammatory drugs to replace heparin for certain applications.

Heparins Increase Endothelial Nitric Oxide Bioavailability by Liberating Vessel-Immobilized Myeloperoxidase

BACKGROUND

Neutrophils and monocytes are centrally linked to vascular inflammatory disease, and leukocyte-derived myeloperoxidase (MPO) has emerged as an important mechanistic participant in impaired vasomotor function. MPO binds to and transcytoses endothelial cells in a glycosaminoglycan-dependent manner, and MPO binding to the vessel wall is a prerequisite for MPO-dependent oxidation of endothelium-derived nitric oxide (NO) and impairment of endothelial function in animal models. In the present study, we investigated whether heparin mobilizes MPO from vascular compartments in humans and defined whether this translates into increased vascular NO bioavailability and function.

METHODS AND RESULTS

Plasma MPO levels before and after heparin administration were assessed by ELISA in 109 patients undergoing coronary angiography. Whereas baseline plasma MPO levels did not differ between patients with or without angiographically detectable coronary artery disease (CAD), the increase in MPO plasma content on bolus heparin administration was higher in patients with CAD (P=0.01). Heparin treatment also improved endothelial NO bioavailability, as evidenced by flow-mediated dilation (P<0.01) and by acetylcholine-induced changes in forearm blood flow (P<0.01). The extent of heparin-induced MPO release was correlated with improvement in endothelial function (r=0.69, P<0.01). Moreover, and consistent with this tenet, ex vivo heparin treatment of extracellular matrix proteins, cultured endothelial cells, and saphenous vein graft specimens from CAD patients decreased MPO burden.

CONCLUSIONS

Mobilization of vessel-associated MPO may represent an important mechanism by which heparins exert antiinflammatory effects and increase vascular NO bioavailability. These data add to the growing body of evidence for a causal role of MPO in compromised vascular NO signaling in humans.

Low molecular weight heparin attenuates multiple organ failure in a murine model of disseminated intravascular coagulation*

OBJECTIVE

Bacterial sepsis causes widespread vascular inflammation that frequently leads to disseminated intravascular coagulation (DIC). Although intravascular coagulation contributes to organ failure, it is often debated whether anticoagulant therapy produces any beneficial effects in patients with DIC. The aim of this study was to document potential beneficial effects of low molecular weight heparin (LMWH) in a lipopolysaccharide-induced DIC model.

DESIGN

Controlled animal experiment combined with an in vitro laboratory study.

SETTING

Academic research laboratory.

SUBJECTS

C57BL/6 mice subjected to two injections of Serratia Marcescens lipopolysaccharide (LPS) resulting in the generalized Shwartzman's reaction as a model for DIC.

INTERVENTIONS

LMWH (5 IU of anti-Xa activity) or saline was administered before both LPS injections and 10 hrs after the first exposure to LPS. To test the effect of LMWH on LPS-driven monocyte inflammatory responses, a human monocyte-human umbilical vein endothelial cell co-culture was used to determine E-selectin expression as a marker of monocyte adherence.

MEASUREMENTS AND MAIN RESULTS

In our murine DIC model, LMWH had no effect on markers of inflammation. In addition, no effect of LMWH was detected on monocyte adherence in the human monocyte-human umbilical vein endothelial cell co-culture. Organ damage, contrarily, was significantly reduced as determined by hepatic necrosis (p < .05), lung epithelial protein leakage (p < .05), and creatinine release from kidneys into plasma (p < .01). LMWH protection from organ failure resulted in an increase in survival (p = .06) in this model for DIC.

CONCLUSIONS

These results demonstrate the significance of blood coagulation in the progression of DIC and hint at a beneficial role for LMWH anticoagulation in the management of DIC.

Heparin-disaccharide affects T cells: inhibition of NF-κB activation, cell migration, and modulation of intracellular signaling

We previously reported that disaccharides (DS), generated by enzymatic degradation of heparin or heparan sulfate, inhibit T cell-mediated immune reactions in rodents and regulate cytokine [tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-8, and IL-1beta] secretion by T cells, macrophages, or intestinal epithelial cells. Here, we investigated the effects of a trisulfated heparin DS (3S-DS) on two aspects of T cell function: secretion of proinflammatory cytokines and migration to an inflamed site. 3S-DS down-regulated nuclear factor-kappaB activity and reduced the secretion of TNF-alpha and interferon-gamma (IFN-gamma) by anti-CD3-activated T cells. In addition, 3S-DS inhibited CXC chemokine ligand 12 (CXCL12; stromal cell-derived factor-1alpha)-dependent migration in vitro and in vivo and decreased CXCL12-induced T cell adhesion to the extracellular matrix glycoprotein, fibronectin (FN). This inhibition was accompanied by attenuation of CXCL12-induced Pyk2 phosphorylation but did not involve internalization of the CXCL12 receptor, CXCR4, or phosphorylation of extracellular-regulated kinase. Despite inhibiting CXCL12-induced adhesion, 3S-DS, on its own, induced T cell adhesion to FN, which was accompanied by phosphorylation of Pyk2. A monosulfated DS showed no effect. Taken together, these data provide evidence that 3S-DS can regulate inflammation by inducing and modulating T cell-signaling events, desensitizing CXCR4, and modulating T cell receptor-induced responses.