Comparative therapeutic strategies for preventing aortic rupture in a mouse model of vascular Ehlers-Danlos syndrome

Vascular Ehlers-Danlos syndrome is a rare inherited disorder caused by genetic variants in type III collagen. Its prognosis is especially hampered by unpredictable arterial ruptures and there is no therapeutic consensus. We created a knock-in Col3a1^+/G182R mouse model and performed a complete genetic, molecular and biochemical characterization. Several therapeutic strategies were also tested. Col3a1^+/G182R mice showed a spontaneous mortality caused by thoracic aortic rupture that recapitulates the vascular Ehlers-Danlos syndrome with a lower survival rate in males, thin non-inflammatory arteries and an altered arterial collagen. Transcriptomic analysis of aortas showed upregulation of genes related to inflammation and cell stress response. Compared to water, survival rate of Col3a1^+/G182R mice was not affected by beta-blockers (propranolol or celiprolol). Two other vasodilating anti-hypertensive agents (hydralazine, amlodipine) gave opposite results on aortic rupture and mortality rate. There was a spectacular beneficial effect of losartan, reversed by the cessation of its administration, and a marked deleterious effect of exogenous angiotensin II. These results suggest that blockade of the renin angiotensin system should be tested as a first-line medical therapy in patients with vascular Ehlers-Danlos syndrome.

Vascular Ehlers-Danlos syndrome (vEDS) is a rare vascular genetic disease leading to life-threatening arterial and colonic fragility in young adulthood. We created a new mutant mouse with a typical disease-causing variant in the gene responsible for vEDS. This mouse recapitulates the vEDS vascular features with spontaneous mortality due to aortic rupture. We also tested several antihypertensive therapeutic strategies to improve the survival of this mouse. Only one of the 5 tested medications, losartan, which blocks the activity of angiotensin II, a vasoconstricting hormone, improves the survival of this mouse. Moreover, the deleterious effect of angiotensin II administration further highlights the role of angiotensin II on susceptibility to aortic rupture in this mouse. These results support the interest of a therapeutic trial in vEDS patients using angiotensin II receptor blockers.

Targetable cellular signaling events mediate vascular pathology in vascular Ehlers-Danlos syndrome

Vascular Ehlers-Danlos syndrome (vEDS) is an autosomal-dominant connective tissue disorder caused by heterozygous mutations in the COL3A1 gene, which encodes the pro-α 1 chain of collagen III. Loss of structural integrity of the extracellular matrix is believed to drive the signs and symptoms of this condition, including spontaneous arterial dissection and/or rupture, the major cause of mortality. We created 2 mouse models of vEDS that carry heterozygous mutations in Col3a1 that encode glycine substitutions analogous to those found in patients, and we showed that signaling abnormalities in the PLC/IP3/PKC/ERK pathway (phospholipase C/inositol 1,4,5-triphosphate/protein kinase C/extracellular signal-regulated kinase) are major mediators of vascular pathology. Treatment with pharmacologic inhibitors of ERK1/2 or PKCβ prevented death due to spontaneous aortic rupture. Additionally, we found that pregnancy- and puberty-associated accentuation of vascular risk, also seen in vEDS patients, was rescued by attenuation of oxytocin and androgen signaling, respectively. Taken together, our results provide evidence that targetable signaling abnormalities contribute to the pathogenesis of vEDS, highlighting unanticipated therapeutic opportunities.

Skeletal fragility: an emerging complication of Ehlers-Danlos syndrome

Ehlers-Danlos syndrome (EDS) is an emerging cause of skeletal fragility. Mechanism of bone damage are probably multifactorial in line with the different skeletal phenotypes that can be found in clinical practice. A structured approach to clinical management of bone metabolic complication in EDS is proposed.

[EHLERS-DANLOS SYNDROME OF THE HYPERMOBILE TYPE: A MULTISYSTEMIC DISORDER. CONTRIBUTION OF SKIN ULTRASTRUCTURE TO INDIVIDUAL MANAGEMENT]

Ehlers-Danlos syndrome (EDS) represents a heterogeneous group of disorders of the connective tissue structure. Currently, several types are distinguished following a limited set of clinical signs and genetic mutations. However, there is a lack of specificity of most recognized genetic alterations with the current clinical typing. In addition, the criteria from dermatopathology, ultrastructure and biomechanics are not considered. In addition, the established EDS frontiers are hazardous because a series of anatomo-clinical signs are not considered in the classical EDS concept. The hypermobile type EDS represents an example of the diagnostic uncertainties. It results that guidelines based on evidence-based medicine cannot be established. Only an individual management can be offered to the concerned patients.

Effects of disulfiram treatment in patients with Menkes disease and occipital horn syndrome

The clinical and biochemical effects of disulfiram were evaluated in three boys with the disorders characterized by copper deficiency due to the defect of ATP7A. Two suffered from Menkes disease (MD) and one from occipital horn syndrome. Disulfiram was orally given, in addition to a parenteral administration of copper-histidine in the case of MD patients. Serum levels of copper and ceruloplasmin slightly increased in one MD patient, and he showed favorable emotional expression and behavior more often than before according to his caretakers. However, no obvious changes were observed in the other two patients. Serum ratios of noradrenaline to dopamine, and adrenaline to dopamine, which are thought to be the indicators of dopamine β-hydroxylase activity, one of the copper requiring enzymes, were unaltered after disulfiram treatment. No adverse effects were recognized during the treatment period in all patients. Although the major improvement was not observed clinically or biochemically by disulfiram treatment so far, the trial will be continued to see the possible effects in these disorders with copper transport defect.

Syndrome d’Ehlers-Danlos vasculaire

The vascular type of Ehlers-Danlos syndrome (EDS) is a rare genetic disease transmitted as an autosomal dominant trait. It is distinguished from other forms of EDS by its unstable acrogeric morphotype and by vascular, gastrointestinal, and obstetrical complications. Diagnosis is based on various clinical signs, noninvasive imaging, and on the identification of a mutation of the COL3A1 gene, which provides diagnostic certainty but has a sensitivity of only 61%. When two major diagnostic criteria are present, a genetic test should be proposed, performed and its result presented in a multidisciplinary group. The precautionary principle requires that preventive measures be implemented when the diagnosis is suspected. All artery puncture, surgery, and gastrointestinal and uterine endoscopy are contraindicated, permissible only in life-threatening emergencies. Straining against a closed glottis and all other situations or drugs likely to raise blood pressure must be avoided. Contraception must be discussed to avoid pregnancy during the diagnostic period. Arterial lesions suggestive of the disease include dissecting aneurysms of the internal carotid and iliac arteries and of the anterior visceral branches of the abdominal aorta, fusiform aneurysms of the splenic artery, and early onset nontraumatic direct carotid-cavernous fistulae. Early-onset varicose veins, spontaneous peritonitis or unusually important perineal lesions after giving birth should also attract the physician's attention. Psychological treatment and support of patients and their families is essential, to help them both to live with their disease and to deal with the information and screening issues. The prognosis of Ehlers-Danlos syndrome, vascular type, is grim but there is wide interindividual variability and life expectancy is best among patients receiving regular follow-up. Management by an experienced multidisciplinary team, implementation of drastic prevention measures and, depending on the results of the BBEST study, the possible prescription of beta-blockers should help to reduce the risk of complications and justify hope for a real improvement in prognosis in the near future.

Matrix metalloproteinase inhibitor therapy to prevent complications as well as therapy for Ehler-Danlos syndrome

Matrixmetalloproteinase inhibitors have been developed as anti-cancer agents. Their usage in pancreatic cancer and other such malignancies is under trial at present. An interesting undesired-effect of one of these agents is contracture of the hand. Ehler-Danlos syndrome is an inherited group of diseases with varying types. At present there is no known treatment or prevention for the complications associated with this inherited condition. Sometimes it is the adverse events of a drug, which provides an insight into its efficacy for another indication. It is hereby being hypothesized that the matrixmetalloproteinase inhibitors especially marimastat may be an effective drug for treatment of Ehler-Danlos syndrome and/or prevention of its major complications.

Effect of dexamethasone on the assembly of the matrix of fibronectin and on its receptors organization in Ehlers-Danlos syndrome skin fibroblasts

The effect of dexamethasone (DEX) on the expression of fibronectin (FN), proalpha(1)(I) collagen (Col1), integrin alpha(2), alpha(5)and beta(1)subunits mRNAs, were studied by quantitative in situ hybridization (ISH) with radiolabelled probes in relationship with the organization of the extracellular matrix (ECM) of FN in human skin fibroblasts. In particular, two fibroblast strains were analysed, one derived from a control donor, typically organizing a rich ECM of FN, and the other from a patient affected by Ehlers-Danlos syndrome (EDS), which did not assemble the FN-ECM. Treatment of both fibroblast strains with 10(-7) m DEX slightly enhanced the level of FN mRNA (by about 1.5-fold), did not influence the level of alpha(5)subunit mRNA and reduced Col1, alpha(2)and beta(1)integrin subunits mRNAs by 2-3-fold. These results show that, in these cells, DEX coordinately downregulates the expression of Col1 and its specific integrin alpha(2)beta(1). Moreover, DEX regulates in a different manner the alpha(5)and beta(1)subunits forming the main FN receptor (FNR) in skin fibroblasts. Immunofluorescence microscopy evidencing the FN-ECM and integrins containing alpha(5)and beta(1)subunits showed that in control cells DEX induced a slight enhancement of the FN-ECM and of the alpha(5)beta(1)receptors patches. Therefore, in these cells the decrease of beta(1)FN receptor subunit mRNA, as well as the decrease of Col1 and its receptor mRNAs, did not influence the FN-ECM assembly. In EDS fibroblasts, DEX decreased the cytoplasmic accumulation of FN and induced the assembly of a rich FN-ECM through the formation of large FNR integrin patches, codistributing with the FN-ECM. We suggest that in EDS skin fibroblasts DEX corrects the defective FN-ECM favouring the sorting and the organization of FN and its alpha(5)beta(1)integrin receptor.

[Effect of therapy with beta-adrenoblockers and vitamin complexes on indices of oxyproline excretion in various hereditary connective tissue diseases]

Excretion of hydroxyproline with urine was studied in 16 children (5-14 years old) with Marphan-Like syndrome and Marphan, Ehlers-Dunlos and Larson syndromes after therapy involving propranolol and a complex of vitamins (ascorbic acid, riboflavin and pyridoxine) and recommended on the basis of echocardiographic analyses. The therapeutic course appears to cause quantitative and qualitative correction of collagen and apparently of elastin fibrilles development. Depending on initial patterns of hydroxyproline excretion and the syndrome form the correction could be complete or partial, while positive effect of the treatment was stable or provisional. The data obtained suggest that the complex treatment developed might be applied as a preoperative therapy of the patients with Marphan-like syndrome as well as with syndromes of Marphan and Ehlers-Dunlos before thoracoplastics caused by hereditary chest deformation and by impairments of cardiovascular system.

Pregnancy management and successful outcome of Ehlers-Danlos syndrome type IV

Ehlers-Danlos syndrome type IV (EDS IV) is a rare but serious disorder of connective tissue that is characterized by the abnormal production or secretion of type III collagen. Experience with pregnant patients exhibiting this syndrome is limited. This report describes the successful management of a pregnancy in a woman with EDS IV that included activity restriction and complete bed rest after 32 weeks, use of 1-desamino-8-D-arginine vasopressin (DDAVP) before delivery to improve coagulation, and cesarean section before the onset of labor. The possibility of prenatal diagnosis based on genetic linkage studies also is discussed.

Vitamin C and human wound healing

Clinical studies provide evidence that wound healing in subjects judged not deficient in vitamin C can be significantly accelerated with supplements of this nutrient above the recommended daily allowance (RDA). The authors administered daily dosages of 500 to 3,000 mg., which is roughly 8 to 50 times the RDA of 60 mg., to subjects recovering from surgery, other injuries, decubital ulcers, and leg ulcers induced by hemolytic anemia. Genetic impairment of collagen synthesis has also been observed to be responsive to ascorbic acid supplementation in an 8-year-old boy with Type VI Ehlers-Danlos syndrome. Four grams of ascorbic acid daily produced a significant improvement in the quality of newly synthesized collagen but did not alter that formed prior to the supplementation of C. The combined evidence in this review provides a substantial base for further research, both clinical and experimental trials, concerning the interrelationships between vitamin C and the body's healing potential.

[Treatment of the Ehlers-Danlos syndrome with zinc (author's transl)]

Oral administration of zinc sulfate did not improve the clinical conditions in two patients with Ehlers-Danlos-Syndrome type I. Zinc levels in serum and hair were normal before and during treatment.

[A case of Ehlers-Danlos-syndrome and its zinc therapy (author's transl)]

An 8-year-old boy presented a typical Ehlers-Danlos-syndrome. The light- and electromicroscopic findings of both skin- and muscle-biopsy cannot explain the symptoms. A deficiency of zinc and, resulting from this, a defective cohesiveness of collagenous and elastic fibres seems possible. After oral zinc treatment a significant therapeutic effect was seen.

Inherited human collagen lysyl hydroxylase deficiency: ascorbic acid response

A patient is described with congenital hypotonia, lax joints, friable skin, hemorrhagic scars, high-arched palate, and borderline microcornea. Acid hydrolyzed whole skin collagen had a reduced hydroxylysine content of 0.5 residues per 1,000 as compared to 5.1 +/- 0.7 in control skin. Collagen lysyl hydroxylase in dialyzed subcellular fractions of cultured skin fibroblasts required L-ascorbate as a principal cofactor. Activity of this enzyme in cultured skin fibroblasts derived from this patient, his father, and mother were 17%, 66%, and 39% of control values, respectively. Collagen prolyl hydroxylase activity was normal. Pharmacologic amounts of oral vitamin C (4 gm/day) produced an increase and withdrawal resulted in abrupt diminution of urinary excretion of hydroxylysine. Over a two-year period the patient's wound healing and muscle strength improved and corneal diameter increased. Hydroxylysine content of the skin did not increase.

[Efficacy of prolonged therapy with vitamins C and A and radiologic changes in the Ehlers-Danlos syndrome]

Two children of the same sex, almost of equal age, and suffering from the Ehlers-Danlos syndrome were followed up for a period of seven years. One of the children was subjected to a systematic treatment with vitamins C and A, Lipovitan, sulphuric mineral waters, and kinesitherapy. The non-treated child is serving as control person for the treated one. Thus it has been possible to evaluate the efficacy of the therapy administered to the first child and also to state the osseous progressive changes in the non-treated child.