Mandibuloacral dysplasia (MAD) is a rare disease resulting from a mutation of LMNA gene encoding lamins A and C. The most common mutation associated with this disease is a homozygous arginine 527 replacement by histidine. Three female patients originating from two unrelated families from Northeast Egypt were examined. Their growth was retarded; they had microcephaly, widened cranial sutures, prominent eyes and cheeks, micrognathia, dental crowding, hypoplastic mandible, acro-osteolysis of distal phalanges, and joint contractures. In addition, they presented some progeroid features, such as pinched nose, premature loss of teeth, loss of hair, scleroderma-like skin atrophy, spine rigidity, and waddling gait. The clinical presentation of the disease varied between the patient originating from Family 1 and patients from Family 2, suggesting that unknown, possibly epigenetic factors, modify the course of the disease. The first symptoms of the disease appeared at the age of 2.5 (a girl from Family 1), 5, and 3 years (girls from Family 2). All patients had the same, novel homozygous c.1580G4T LMNA mutation, resulting in the replacement of arginine 527 by leucine. Computational predictions of such substitution effects suggested that it might alter protein stability and increase the tendency for protein aggregation, and as a result, might influence its interaction with other proteins. In addition, restriction fragment-length polymorphism analysis performed in 178 unrelated individuals showed that up to 1.12% of inhabitants of Northeast Egypt might be heterozygous carriers of this mutation, suggesting the presence of a founder effect in this area.
European Journal of Human Genetics (2012) 0, 000–000. doi:10.1038/ejhg.2012.77
Mohammad Al-Haggar, Agnieszka Madej-Pilarczyk, Lukasz Kozlowski, Janusz M Bujnicki, Sohier Yahia, Dina Abdel-Hadi, Amany Shams, Nermin Ahmad, Sahar Hamed and
Monika Puzianowska-Kuznicka
Thursday, May 3, 2012
Cardiomyopathy and angiogenesis defects of Wistar rat fetuses of diabetic and hypercholesterolemic mothers
A b s t r a c t
Objective: We aimed to illustrate the histogenesis, lactic dehydrogenase isoenzymes electrophoresis, and DNA damage of cardiac muscles and blood vessels during prenatal life of maternal diabetic or hypercholesterolemic mother.
Methods: Eighty fertile male and virgin female Wistar rats (1 male/3 females), weighing approximately 130 g, were mated and zero date of gestation was determined. Diabetes was induced at the fifth day of gestation by intraperitoneal injection of a single dose of 60 mg streptozotocin/kg body weight in citrate buffer, pH 4.6. At the same time, hypercholesterolemia was carried out by feeding virgin rats a diet containing 3% cholesterol for 6 wk before the onset of conception. Pregnant rats were arranged into three groups: control, diabetic, and hypercholesterolemic (n = 20). The animals were sacrificed and embryos were separated at 7-, 13-, 15-, 17-, and 19 d old, respectively, and subjected to light and transmission electron microscopy, lactic dehydrogenases isoenzymes electrophoresis, DNA fragmentation, and comet assay. The sera of the mothers were examined for fasting glucose level, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, and creatine phosphokinase levels.
Results: Diabetic and hypercholesterolemic mothers exhibited a significant increase of sera cholesterol level, low-density lipoprotein, and creatine phosphokinase activity. Histologic findings of embryos of diabetic and hypercholesterolemic mothers revealed cardiomyopathy and malformation of blood vessels with an apparent degeneration of their endothelium. Transmission electron microscopy possessed massive necrosis of muscle fibers, disorganization of Z and I bands, and mitochondrial damage. Lactic dehydrogenase isoenzyme electrophoresis was altered and genomic DNA fragmentation was markedly increased.
Conclusion: Maternal diabetes or hypercholesterolemia led to marked alterations in blood vessel differentiation as well as to cardiomyopathy during prenatal growth as assessed by the disruption of fine structures, abnormal lactic dehydrogenase isoenzymes electrophoresis, and an increase of DNA damage. These may be attributed to the marked oxidative stress and liberation of free oxygen radicals, which interrupted the myocardium structure and function during organogenesis.
Nutrition, 20 April, 2012, PMID: 22521615 [PubMed - as supplied by publisher]
Objective: We aimed to illustrate the histogenesis, lactic dehydrogenase isoenzymes electrophoresis, and DNA damage of cardiac muscles and blood vessels during prenatal life of maternal diabetic or hypercholesterolemic mother.
Methods: Eighty fertile male and virgin female Wistar rats (1 male/3 females), weighing approximately 130 g, were mated and zero date of gestation was determined. Diabetes was induced at the fifth day of gestation by intraperitoneal injection of a single dose of 60 mg streptozotocin/kg body weight in citrate buffer, pH 4.6. At the same time, hypercholesterolemia was carried out by feeding virgin rats a diet containing 3% cholesterol for 6 wk before the onset of conception. Pregnant rats were arranged into three groups: control, diabetic, and hypercholesterolemic (n = 20). The animals were sacrificed and embryos were separated at 7-, 13-, 15-, 17-, and 19 d old, respectively, and subjected to light and transmission electron microscopy, lactic dehydrogenases isoenzymes electrophoresis, DNA fragmentation, and comet assay. The sera of the mothers were examined for fasting glucose level, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, and creatine phosphokinase levels.
Results: Diabetic and hypercholesterolemic mothers exhibited a significant increase of sera cholesterol level, low-density lipoprotein, and creatine phosphokinase activity. Histologic findings of embryos of diabetic and hypercholesterolemic mothers revealed cardiomyopathy and malformation of blood vessels with an apparent degeneration of their endothelium. Transmission electron microscopy possessed massive necrosis of muscle fibers, disorganization of Z and I bands, and mitochondrial damage. Lactic dehydrogenase isoenzyme electrophoresis was altered and genomic DNA fragmentation was markedly increased.
Conclusion: Maternal diabetes or hypercholesterolemia led to marked alterations in blood vessel differentiation as well as to cardiomyopathy during prenatal growth as assessed by the disruption of fine structures, abnormal lactic dehydrogenase isoenzymes electrophoresis, and an increase of DNA damage. These may be attributed to the marked oxidative stress and liberation of free oxygen radicals, which interrupted the myocardium structure and function during organogenesis.
Nutrition, 20 April, 2012, PMID: 22521615 [PubMed - as supplied by publisher]
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