Global periorbital skin rejuvenation by a topical eye cream containing low molecular weight heparan sulfate (LMW-HS) and a blend of naturally derived extracts.

BACKGROUND: Maintaining a youthful appearance is a priority for many people. Global eye rejuvenation is sought more frequently and at a younger age than other treatments. Major concerns around the eye area are periorbital hyperpigmentation, puffiness, and lines and wrinkles. Glycosaminoglycans (GAGs) are complex carbohydrates that modulate skin health, repair and renew skin's appearance. Heparan sulfate (HS) is the most biologically active GAG, although it is too large and polar to penetrate the skin. Low Molecular Weight Heparan Sulfate (LMW-HS) is a smaller version of HS designed for skin penetration while preserving its activity. In this study, we investigated the effects of a topical eye cream containing LMW-HS and a blend of naturally derived extracts to address global periorbital rejuvenation. METHOD: A single-center, open-label study including female and male subjects (n = 15) was conducted to evaluate the efficacy and tolerability of an eye cream containing LMW-HS and a blend of naturally derived extracts applied twice daily for 12 weeks. RESULTS: Improvements in the appearance of periorbital hyperpigmentation and fine and coarse wrinkles were observed as early as week 2 with continuous improvement up to 12 weeks. Decrease in puffiness (73%) and dark circles (93%) were reported by subjects. The test product was highly rated by subjects on performance and attributes and was well tolerated by all the subjects in this study. CONCLUSION: Results demonstrated that an eye cream containing LMW-HS and a blend of naturally derived extracts achieved global skin rejuvenation by improving appearance of periorbital hyperpigmentation, puffiness, and fine and coarse wrinkles.

Design and synthesis of structurally defined heparan sulfate (HS)-FK506 conjugates as an exogenous approach to investigate biological functions of nucleus HS.

Although heparan sulfate (HS) is widely implicated in numerous physiological and pathological processes, the biological function of nucleus HS remains underexplored, largely due to its complex structure and high hydrophilic property. To supplement these efforts, ideal vehicles are drawing attention as they combine attractive features including lipid solubility for penetrating cell membrane, high affinity binding to its target receptor, metabolic stability, and no cellular actions resulting in toxicity. Herein, we develop a convenient and promising strategy to prepare HS-FK506 conjugates for membrane transport and entry into nucleus, where click chemistry takes easily place between the exocyclic allyl group of a clinic drug FK506 and thiol as a handle incorporated into HS analogues. HS derivatives for constructing the conjugates were synthesized using a cutting-edge chemoenzymatic method. Meantime, [35S] labeled 3'-phosphoadenosine 5'-phosphosulfate (PAP35S) and [14C] glucuronic acid (Glc A) were adopted to label HS-FK506 conjugates, respectively, to evaluate their efficiency of nucleus entry, as a result, 14C Glc A was sensitive, effective and reliable whereas PAP35S gave rise to a mixture of labeled compounds, hampering the understanding of structure-function relationship of nucleus HS. Compared with the corresponding HS, the amount of HS-FK506 conjugates to translocate into nucleus from radioactive assay experiments sharply increased, e.g. tridecasaccharide-FK506 1d increased by approximate 10 folds, offering a simple and robust platform for enabling hydrophilic compounds including carbohydrates to translocate into nucleus and shedding light on their biological functions.

Heparán sulfatos, amiloidosis y neurodegeneración / Heparan sulphates, amyloidosis and neurodegeneration

Introducción. Numerosos trastornos neurodegenerativos se han asociado directamente a la acumulación de fibras amiloides. Estas fibras están formadas por proteínas o péptidos con conformaciones alteradas y que se agregan in vivo en asociación con polisacáridos de tipo heparán sulfatos. Objetivos. Examinar los conceptos más recientes sobre la biología de los heparán sulfatos y su papel en la agregación del péptido Abeta, de la proteína tau, de la alfa-sinucleína y de los priones, y analizar sus implicaciones en trastornos neurodegenerativos como las enfermedades de Alzheimer y de Parkinson y las enfermedades priónicas. Desarrollo. In vitro, los heparán sulfatos han desempeñado un papel importante en el proceso de oligomerización y fibrilación de proteínas o péptidos amiloidógenos, en la estabilización de estos cuerpos y su resistencia a la proteólisis, participando así en la formación de una gran variedad de fibras amiloides. Los heparán sulfatos se han relacionado también con el proceso de internalización de fibras proamiloides durante el proceso de propagación intercelular (spreading) considerado como central en la evolución de las proteinopatías, cuyo mejor ejemplo es la enfermedad de Alzheimer. Conclusión. Este trabajo sugiere que las estructuras finas de los heparán sulfatos, sus localizaciones celulares y tisulares, así como sus concentraciones locales, pueden regular los procesos de amiloidosis. Avances en la comprensión de esta área de la gliconeurobiología permitirán mejorar la comprensión de los mecanismos celulares y moleculares del proceso neurodegenerativo (AU)

Introduction. A number of neurodegenerative disorders have been linked directly to the accumulation of amyloid fibres. These fibres are made up of proteins or peptides with altered structures and which join together in vivo in association with heparan sulphate-type polysaccharides. AIMS. To examine the most recent concepts in the biology of heparan sulphates and their role in the aggregation of the peptide Abeta, of tau protein, of alpha-synuclein and of prions. The study also seeks to analyse their implications in neurodegenerative disorders such as Alzheimers and Parkinson’s disease and prion diseases. Development. In vitro, heparan sulphates have played an important role in the process of oligomerisation and fibrillation of amyloidogenic proteins or peptides, in the stabilisation of these bodies and their resistance to proteolysis, thereby participating in the formation of a wide range of amyloid fibres. Heparan sulphates have also been related to the internalisation of pro-amyloid fibres during the process of intercellular propagation (spreading), which is considered to be crucial in the development of proteinopathies, the best example of which is Alzheimers disease. Conclusion This study suggests that the fine structures of heparan sulphates, their localisation in cells and tissues, together with their local concentration, may regulate the amyloidosis processes. The advances made in the understanding of this area of glyconeurobiology will make it possible to improve the understanding of the cell and molecular mechanisms underlying the neurodegenerative process (AU)

Controlled delivery of the heparan sulfate/FGF-2 complex by a polyelectrolyte scaffold promotes maximal hMSC proliferation and differentiation.

Growth factors and other regulatory molecules are required to direct differentiation of bone marrow-derived human mesenchymal stem cells (hMSC) along specific lineages. However, the therapeutic use of growth factors is limited by their susceptibility to degradation, and the need to maintain prolonged local release of growth factor at levels sufficient to stimulate hMSC. The aim of this study was to investigate whether a device containing heparan sulfate (HS), which is a co-factor in growth factor-mediated cell proliferation and differentiation, could potentiate and prolong the delivery of fibroblast growth factor-2 (FGF-2) and thus enhance hMSC stimulation. To this aim, we synthesized cationic polyelectrolyte polymers covalently and non-covalently anchored to HS and evaluated their effect on hMSC proliferation. Polymers non-covalently bound to HS resulted in the release of an HS/FGF-2 complex rather than FGF-2 alone. The release of this complex significantly restored hMSC proliferation, which was abolished in serum-free medium and only partially restored by the release of FGF-2 alone as occurred with polymer covalently bound to HS. We also demonstrate that exposure to HS/FGF-2 during early growth but not during post-confluence is essential for hMSC differentiation down the fibroblast lineage, which suggests that both factors are required to establish the correct stem cell commitment that is necessary to support subsequent differentiation. In conclusion, the delivery platform described here is a step towards the development of a new class of biomaterial that enables the prolonged, non-covalent binding and controlled delivery of growth factors and cofactors without altering their potency.

PI-88 and novel heparan sulfate mimetics inhibit angiogenesis.

The heparan sulfate (HS) mimetic PI-88 is a promising inhibitor of tumor growth and metastasis expected to commence phase III clinical evaluation in 2007 as an adjuvant therapy for postresection hepatocellular carcinoma. Its anticancer properties are attributed to inhibition of angiogenesis via antagonism of the interactions of angiogenic growth factors and their receptors with HS. It is also a potent inhibitor of heparanase, an enzyme that plays a key role in both metastasis and angiogenesis. A series of PI-88 analogs have been prepared with enhanced chemical and biological properties. The new compounds consist of single, defined oligosaccharides with specific modifications designed to improve their pharmacokinetic properties. These analogs all inhibit heparanase and bind to the angiogenic fibroblast growth factor 1 (FGF-1), FGF-2, and vascular endothelial growth factor with similar affinity to PI-88. However, compared with PI-88, some of the newly designed compounds are more potent inhibitors of growth factor-induced endothelial cell proliferation and of endothelial tube formation on Matrigel. Representative compounds were also tested for antiangiogenic activity in vivo and were found to reduce significantly blood vessel formation. Moreover, the pharmacokinetic profile of several analogs was also improved, as evidenced primarily by lower clearance in comparison with PI-88. The current data support the development of HS mimetics as potent antiangiogenic anticancer agents.

Danaparoid sodium reduces ischemia/reperfusion-induced liver injury in rats by attenuating inflammatory responses.

This study was undertaken to examine the mechanism by which danaparoid sodium (DS), a heparinoid that contains mainly heparan sulfate, prevents reperfusion-induced hepatic damage in a rat model of ischemia/reperfusion (I/R)-induced liver injury. Administration of DS significantly reduced liver injury and inhibited the decrease in hepatic tissue blood flow in rats. DS attenuated hepatic I/R-induced increases in hepatic tissue levels of tumor necrosis factor (TNF) and myeloperoxidase (MPO) in vivo. In contrast, neither monocytic TNF production nor neutrophil activation was inhibited by DS in vitro. DS enhanced I/R-induced increases in levels of calcitonin-gene related peptide (CGRP), a neuropeptide released from sensory neurons, and of 6-ketoprostaglandin (PG) F (1a) , a stable metabolite of PGI (2) , in liver tissues. The therapeutic effects of DS were not seen in animals pretreated with capsazepine, an inhibitor of sensory neuron activation. The distribution of heparan sulfate in the perivascular area was significantly increased by DS administration in this rat model. DS significantly increased CGRP release from isolated rat dorsal root ganglion neurons (DRG) in vitro, while DX-9065a, a selective inhibitor of activated factor X, did not. DS enhanced anandamide-induced CGRP release from DRG in vitro. These observations strongly suggested that DS might reduce I/R-induced liver injury in rats by attenuating inflammatory responses. These therapeutic effects of DS might be at least partly explained by its enhancement of sensory neuron activation, leading to the increase the endothelial production of PGI (2) .

Bone-specific heparan sulfates induce osteoblast growth arrest and downregulation of retinoblastoma protein.

The heparan sulfate (HSs) sugars of the extracellular matrix (ECM) play a key role during both development and wound repair in regulating the flow of growth and adhesive factors across their cell surface receptors. The aim of this study was to assess the structural and functional differences of HS chains extracted from the conditioned media (soluble), cell surface, and ECM of primary human osteoblast cultures, and to analyze their effects on osteoblast cell growth. HS chains from these compartments were characterized through a combination of enzymatic degradation, anion exchange chromatography, and molecular sieving. Although the chains were all approximately the same size, they varied systematically in their sulfate content, suggesting differences in their protein-binding domains. When added to pre-confluent hFOB1.19 osteoblast cultures, HS doses exceeding 500 ng/ml inhibited proliferation, without affecting viability, irrespective of their origin. Furthermore, HS doses of 500 ng/ml also downregulated retinoblastoma, Cyclin A and CDK1 protein expression, indicating that high doses of osteoblast HS negatively regulate cell cycle, resulting in growth arrest; when high doses of HS were withdrawn after a prolonged period, linear cell growth was reestablished. Thus, despite differences in sulfation, HS from either the soluble, cell surface, or matrix compartments of primary human osteoblast cultures are functionally similar with respect to their effects on growth. Binding assays revealed that the HS chains bound TGFbeta1, a known inhibitor of osteoprogenitor growth, at higher affinity than a suite of other bone-related, heparin-binding growth factors. Overcoming such sugar-mediated inhibition may prove important for wound repair.

Danaparoid: a review of its use in thromboembolic and coagulation disorders.

UNLABELLED: Danaparoid (danaparoid sodium) is a low molecular weight heparinoid which has undergone clinical study for use as continued anticoagulant therapy in patients with heparin-induced thrombocytopenia (HIT), for the prophylaxis and treatment of deep vein thrombosis (DVT), and for the treatment of disseminated intravascular coagulation (DIC). A nonblind study in patients with HIT has reported that complete clinical resolution is significantly more likely in patients receiving danaparoid than in patients receiving dextran 70. In addition, retrospective analyses and noncomparative data support the use of danaparoid for continued anticoagulant therapy in patients with HIT. Studies in patients undergoing hip surgery have shown that danaparoid significantly reduces the incidence of postoperative DVT compared with aspirin, warfarin, dextran 70 and heparin-dihydroergotamine, while additional data suggest no difference between danaparoid, enoxaparin and dalteparin. In patients undergoing abdominal or thoracic surgery for removal of a malignancy, danaparoid reduced the incidence of postoperative DVT compared with placebo, but showed no significant difference when compared with unfractionated heparin (UFH). Two studies have compared danaparoid with UFH in the prophylaxis of DVT following acute ischaemic stroke; twice daily danaparoid was significantly superior to UFH whereas there was no significant difference between a once-daily dosage and UFH. Danaparoid did not differ from UFH in terms of efficacy in the treatment of existing DVT. In all comparative studies examining the efficacy of danaparoid in the prophylaxis or treatment of DVT (versus warfarin, dextran 70, enoxaparin, dalteparin, aspirin, heparin-dihydroergotamine, UFH and placebo), the incidence of haemorrhagic complications did not differ between treatment groups. In patients with DIC, 61.9% of those patients receiving danaparoid experienced either disappearance or reduction of symptoms of DIC whereas 62% of those receiving UFH showed either no change or aggravation of their symptoms. There was no significant difference between treatment groups in tolerability or overall improvement of DIC. CONCLUSIONS: Danaparoid is an effective anticoagulant agent which has undergone clinical evaluation in a wide range of disease indications. Current guidelines support the use of danaparoid in prophylaxis of DVT following ischaemic stroke, and in patients who develop HIT. Danaparoid has shown efficacy in DIC, and for DVT prophylaxis in patients undergoing hip surgery although further data are required to establish the role of danaparoid in these indications. In particular, double-blind trials comparing danaparoid with such recommended therapies as the low molecular weight heparins will provide more definitive data on the place of danaparoid in the clinical management of these conditions and ultimately lead to improved patient outcomes.

Pharmacokinetic studies of dalteparin (Fragmin), enoxaparin (Clexane), and danaparoid sodium (Orgaran) in stable chronic hemodialysis patients.

BACKGROUND: Low molecular weight heparins (LMWHs) and danaparoid are an alternative to unfractionated heparin (UH) for anticoagulation during hemodialysis. Few data are available concerning their duration of action and whether drug accumulation occurs with continued use. We performed a prospective randomized study of the pharmacokinetics of dalteparin and enoxaparin plus danaparoid in 21 hemodialysis patients. METHODS: Patients were randomly assigned to administration of enoxaparin, 40 mg; dalteparin, 2,500 U; or danaparoid, 34 U/kg, for 4 weeks. Antifactor Xa levels were measured at the end of weeks 1 and 4 immediately before the injection and at prescribed intervals up to 48 hours postinjection. RESULTS: No bleeding or thrombotic episodes occurred during the study. Mean antifactor Xa activities 4 hours postinjection were 0.2 +/- 0.035 (SEM), 0.38 +/- 0.028, and 0.54 +/- 0.051 U/mL week 1 and 0.26 +/- 0.038, 0.40 +/- 0.055, and 0.64 +/- 0.050 U/mL week 4 for dalteparin, enoxaparin, and danaparoid, respectively. Both weeks 1 and 4, antifactor Xa activity 3 hours postdose was significantly greater for danaparoid sodium compared with enoxaparin and dalteparin. There were no significant differences between antifactor Xa activity week 4 versus week 1 for enoxaparin and dalteparin; however, danaparoid sodium levels during dialysis were significantly greater after 4 weeks of treatment (P = 0.0328, 1 hour; P = 0.003, 2 hours; P = 0.0128, 3 and 4 hours). CONCLUSION: Dalteparin and enoxaparin provide adequate anticoagulation for hemodialysis using single bolus injections at relatively low doses. Danaparoid sodium at the current recommended dosage resulted in greater anticoagulation than enoxaparin or dalteparin and may have an

Heparan sulfate enhances invasion by human colon carcinoma cell lines through expression of CD44 variant exon 3.

CD44 variant exon (CD44v) 3 is a heparan sulfate-binding isoform of CD44. The role of CD44v3 in invasion and metastasis associated with heparan sulfate in colon cancer cell lines and cases of colon cancer was examined. Expression of CD44v3 mRNA and protein was observed in five of six human colorectal cancer cell lines. Colo320 and WiDr cells expressed CD44v3 at high levels. Heparan sulfate treatment increased the invasive activity of Colo320 and WiDr cells to rates 14.3 and 12.6 times higher, respectively, than that of untreated cells. However, heparan sulfate treatment did not affect cell growth. Repression of CD44v3 protein production by antisense S-oligodeoxynucleotide treatment reduced the binding affinities and capacities for heparan sulfate by Colo320 and WiDr cells in comparison with that of control cells, and it also reduced the invasiveness of both cell lines to one-fifth that of control cells. In heparan sulfate-treated Colo320 cells, the levels of CD44v3 protein in the Triton X-100-insoluble fraction and moesin-precipitated fraction were increased, suggesting that heparan sulfate treatment facilitates association of CD44 molecules with the cytoskeleton. Immunohistochemical analysis showed CD44v3 to be expressed in 21 of 37 (57%) colorectal cancer cases. Positive CD44v3 expression was associated with more advanced pathological stage and poorer prognosis than negative CD44v3 expression. These data support a role for CD44v3 in invasion and metastasis by colorectal carcinoma cells.

A beta and perlecan in rat brain: glial activation, gradual clearance and limited neurotoxicity.

A beta1-40 and perlecan (A beta + perlecan) were infused into rat hippocampus for 1 week via osmotic pumps. At the end of the infusion a deposit of A beta immunoreactive material was found surrounding the infusion site. No neurons could be identified within this A beta deposit. The neuron-free area resulting from A beta + perlecan was significantly larger than that found after infusions of A beta40-1 and perlecan (reverse A beta + perlecan), perlecan alone or phosphate-buffered saline vehicle. Following infusion of A beta + perlecan, the glial cells segregated in a manner similar to that associated with compacted amyloid plaques in Alzheimer's disease (AD). Activated microglia/macrophages were prevalent within the A beta deposit while the perimeter of the deposit was delimited by reactive astrocytes. Thioflavin S and Congo red staining indicated a beta-pleated sheet conformation of the A beta deposits, implying formation of fibrils. Intact, apparently healthy neurons were found immediately adjacent to the A beta + perlecan deposit. In contrast, reverse A beta peptide did not form congophilic deposits despite the presence of perlecan. Apoptotic profiles visualized with bisbenzamide or TUNEL staining of fragmented DNA were not seen at any of the infusion sites, yet were readily seen in hippocampal sections from animals treated with kainic acid. At 8 weeks, A beta immunoreactivity, Thioflavin S and Congo red staining was reduced, indicating that A beta was being cleared. There also was no evidence of neuron loss by Nissl or TUNEL staining. The zone of apparent necrosis did not expand between 1 and 8 weeks, and in some instances appeared to contract. The consistency of the A beta + perlecan infusion method in producing reliable A beta amyloid deposits permits estimates of the rate at which fibrillar A beta amyloid can be removed from the brain, and may provide a useful model to study this process in vivo. However, the absence of clearly identifiable degenerating/dying neurons at the 1 or 8 week survival times suggests that either fibrillar A beta + perlecan slowly displaced the brain parenchyma during infusion, or neurons were killed very gradually during the process of clearing the A beta.

Danaparoid sodium.

Danaparoid sodium (Orgaran, Organon) is a heparinoid glycosamino-glycuronan antithrombotic agent approved for the prophylaxis of post-operative deep vein thrombosis (DVT), which may lead to pulmonary embolism (PE) in patients undergoing elective hip replacement surgery. Danaparoid is a low molecular weight heparinoid consisting of a mixture of heparan sulphate (84%), dermatan sulphate (12%) and small amounts of chondroitin sulphate (4%), whose antithrombotic activity has been well established. Its pharmacological effect is exerted primarily by inhibiting Factors Xa (FXa) and IIa (FIIa) at a ratio greater than heparin, with a minimal effect on platelet function. Danaparoid exhibits low cross-reactivity with heparin-induced antibodies when compared with heparin or low molecular weight heparins (LMWH), thereby making it an excellent choice for the management of heparin-induced thrombocytopenia (HIT). It has excellent bioavailability following s.c. injection. Danaparoid has little effect on routine coagulation tests (activated partial thromboplastin time [aPTT], prothrombin time [PT], and thrombin time [TT]). Patients with elevated serum creatinine should be monitored carefully. For its FDA approved indication (DVT prophylaxis during hip replacement surgery), its cost per day is approximately eight times more than LMWH. Even though monitoring is not routinely necessary according to the manufacturer for its approved indication, monitoring is frequently necessary when it is used in other clinical scenarios. Its higher cost than comparable therapies for DVT prophylaxis and the low availability of the FXa assay in most non-tertiary care hospitals has limited the widespread use of danaparoid. Danaparoid has been found to be effective in the treatment of HIT although this is an off label use, despite being the most frequent reason why danaparoid is used.

A chronopharmacodynamic study on standard heparin, a low molecular weight heparin (nadroparin) and danaproid: establishing and comparing the daily variations of these drugs in rats.

The effects of dosing time on the anticoagulant activity of unfractionated heparin, low molecular weight heparin (nadroparin) and danaproid were investigated. The chronopharmacological comparisons of the drugs were done on the anti-Xa, anti-IIa activities and activated partial thromboplastin time assays. Several dosing times were considered and an analysis based on a population approach was adopted. Under unfractionated heparin, the pharmacological activities did not exhibit significant daily variations. In contrast, significant daily profiles were observed in all the biological assays performed with low molecular weight heparin. Anti-Xa and anti-IIa activities showed some fluctuations over a 24-hour period with a peak at noon. As for the variations of the activated partial thromboplastin time, two peaks were noted early in the morning and at the beginning of nightfall. As for danaproid, only a daytime maximum of anti-Xa activity could be found.

Heparin induced thrombocytopenia: diagnosis and contemporary antithrombin management.

Heparin-induced thrombocytopenia (HIT) may be complicated by severe thrombotic complications and death. Currently no specific laboratory test is available to make the diagnosis. When HIT is clinically suspected, heparin should be discontinued immediately. While no specific therapy for HIT exists, there is increasing evidence that acute antithrombin therapy may significantly reduce morbidity and mortality. Among several agents, the direct antithrombins, such as r-hirudin and argatroban, look the most promising for acute treatment.

Pharmacokinetics of danaparoid sodium, dalteparin sodium and heparin determined by inhibitory effect on the activated coagulation factor X activity after single intravenous administration in rabbits.

The inhibitory effect on the activated coagulation factor X activity (anti-Xa activity) in plasma and urine of danaparoid sodium (DAS, CAS 9005-49-6) was compared with that of dalteparin sodium (DLS, CAS 9041-08-1) and heparin (CAS 9005-49-6) after single intravenous administration at a dose of 640 anti-Xa U/kg to male rabbits. The elimination of half-life of DAS was 9.90 h and was 6.0 times longer than that of DLS and 16.5 times longer than that of heparin. The area under the plasma concentration-time curve (AUC) of DAS was 47.13 +/- 14.55 anti-Xa U.h/ml and was 2.4 times larger than that of DLS and 2.9 times larger than that of heparin. The urinary cumulative excretion of anti-Xa activity of DAS and DLS was 42.6 +/- 6.4% and 16.4 +/- 0.8% of dose, respectively, in 24 h after dosing, respectively. But the anti-Xa activity in urine was not detected at any sampling points after administration of heparin. DAS has a longer elimination half-life and a higher renal excretion of anti-Xa activity than that of DLS and heparin. Therefore, in comparison to DLS and heparin, it seems that the anticoagulant activity of DAS has a long duration.

Altered distribution of heparan sulfate proteoglycans in psoriasis.

Heparan sulfate proteoglycans (HSPGs) are components of the basement membrane (BM) of various tissues. They consist of a core protein and negatively charged glycosaminoglycan side chains: the heparan sulfate (HS) moieties. In psoriasis, uninvolved skin of psoriasis patients and in normal skin, the distribution of HSPGs was studied immunohistochemically by means of three different monoclonal antibodies: JM-72, directed against the HSPG-core protein, JM-13 against the sulfated domains of HS and JM-403 against the unmodified/low sulfated parts of HS. In psoriasis JM-13 staining was consistently absent in the tips of the dermal papillae, whereas JM-13 showed a continuous staining in the BM of uninvolved and normal skin. JM-403 staining was present in BM of all specimens. In addition, a honeycomb-like staining was found in epidermis of normal skin and to a lesser extent in uninvolved skin, due to binding with plasma membrane-associated HS. In psoriasis this JM-403 staining of the epidermis was invariably absent. JM-72 showed a continuous staining of BM in all biopsies. In conclusion, normal human skin and involved psoriatic skin show clear differences in expression of HS. These data may provide insight into the role of HSPGs in psoriasis, which remains further to be elucidated.

Danaparoid. A review of its pharmacology and clinical use in the management of heparin-induced thrombocytopenia.

Danaparoid, a low molecular weight heparinoid consisting of a mixture of heparan, dermatan and chondroitin sulfates, has well established antithrombotic activity. The drug has a high antifactor Xa to antifactor IIa (thrombin) activity ratio, a low tendency to cause bleeding and minimal effects on the fibrinolytic system. Danaparoid has a low cross-reactivity rate with heparin-associated antiplatelet antibodies (0 to 20%; mean approximately 10%). This represents a significant advantage over low molecular weight heparins (LMWHs) as a potential replacement agent for unfractionated heparin (UFH) in patients with immune-mediated (type II) heparin-induced thrombocytopenia (HIT). In a worldwide compassionate-use programme involving a total of 667 patients with HIT to date, 93% of danaparoid treatment courses were considered to be successful. Thrombocytopenia resolved in 91% of episodes. In a multicentre randomised comparative trial of danaparoid and dextran in patients with HIT plus thrombosis (HITT), significantly more danaparoid than dextran recipients had resolution of thromboses, and an effective clinical response was achieved in significantly more danaparoid recipients. Results of a retrospective case-controlled study of danaparoid and ancrod in patients with HITT showed significantly fewer new or progressive thromboses with danaparoid. In the compassionate-use programme, danaparoid was associated with a mortality rate of 10.4% during treatment (up to 3.5 years) and 7.8% during the follow-up period (3 months). 14 of 114 deaths during the follow-up period were considered to be related to danaparoid therapy. A mortality rate of 23.5% was reported in patients accepted for but not treated with, danaparoid. Mortality rates with danaparoid, ancrod and dextran in the comparative studies were similar (7, 11 and 12%, respectively). Severe bleeding was reported in 3.1% of patients in the compassionate-use programme, persistent or recurrent thrombocytopenia in 2.6% and new thromboembolic events/extension of existing thrombosis in 1.7%. The incidence of bleeding was similar with danaparoid and dextran in a comparative trial. Although in vitro cross-reactivity does not always translate into clinical cross-reactivity, testing is currently recommended, when possible, before initiation of danaparoid therapy. Thus, danaparoid appears to be an effective and well tolerated replacement agent for UFH in many patients with HIT who require further anticoagulation. The drug has low cross-reactivity with HIT-associated antibodies. Further comparative trials are needed to confirm these promising findings.

[Heparan sulfate: its kinetic effects on fibrinolytic-coagulative parameters after oral administration]. / Eparansolfato: cinetica degli effetti su parametri fibrinolitico-coagulativi dopo somministrazione orale.

The effects of the oral administration of 100 or 200 mg of heparan sulphate or placebo over time were assessed in nine healthy volunteers. Blood samples were collected at 1, 2, 4, 6, 8 and 12 hours after administration to assay prothrombin activity, partially activated thromboplastin time, and the activation to tPA and PAI-1. A significant increase (P < 0.001) of tPA activity and a reduced inhibition of fibrinolytic systems by PAI-1 were observed. These effects, which were clearly dose-dependent, appeared 2 hours after administration and persisted for 6-8 hours. On the contrary, no changes were recorded in coagulative tests at the doses used.

Differences in the solubility and susceptibility to proteolytic degradation of basement-membrane components in adult and embryonic mouse tissues.

We have studied susceptibility of basement membranes in a variety of tissues to solubility in guanidine hydrochloride and to proteolytic degradation by trypsin and thermolysin. Unfixed sections from embryonic and adult mouse tissues and the EHS tumor were subjected to solvent buffers or digested with enzymes. The retention or disappearance of the basement-membrane components nidogen, laminin, collagen IV, and heparan sulfate proteoglycan was subsequently assayed by immunofluorescence. Our data showed that in all tissues nidogen was the most readily solubilized component and the most susceptible to proteolytic degradation. With few exceptions, nidogen in embryonic tissues was more susceptible to degradation than that in adult tissues, and this correlated well with the susceptibility of the other basement-membrane components to be degraded. We conclude that basement membranes differ quite markedly in their solubility and their susceptibility to proteolytic degradation and that these properties reflect differences in their molecular structure.