Partial lipodystrophy with severe insulin resistance and adult progeria Werner syndrome

Abstract

BackgroundLaminopathies, due to mutations in LMNA, encoding A type-lamins, can lead to premature ageing and/or lipodystrophic syndromes, showing that these diseases could have close physiopathological relationships. We show here that lipodystrophy and extreme insulin resistance can also reveal the adult progeria Werner syndrome linked to mutations in WRN, encoding a RecQ DNA helicase.MethodsWe analysed the clinical and biological features of two women, aged 32 and 36, referred for partial lipodystrophic syndrome which led to the molecular diagnosis of Werner syndrome. Cultured skin fibroblasts from one patient were studied.ResultsTwo normal-weighted women presented with a partial lipodystrophic syndrome with hypertriglyceridemia and liver steatosis. One of them had also diabetes. Both patients showed a peculiar, striking lipodystrophic phenotype with subcutaneous lipoatrophy of the four limbs contrasting with truncal and abdominal fat accumulation. Their oral glucose tolerance tests showed extremely high levels of insulinemia, revealing major insulin resistance. Low serum levels of sex-hormone binding globulin and adiponectin suggested a post-receptor insulin signalling defect. Other clinical features included bilateral cataracts, greying hair and distal skin atrophy. We observed biallelic WRN null mutations in both women (p.Q748X homozygous, and compound heterozygous p.Q1257X/p.M1329fs). Their fertility was decreased, with preserved menstrual cycles and normal follicle-stimulating hormone levels ruling out premature ovarian failure. However undetectable anti-müllerian hormone and inhibin B indicated diminished follicular ovarian reserve. Insulin-resistance linked ovarian hyperandrogenism could also contribute to decreased fertility, and the two patients became pregnant after initiation of insulin-sensitizers (metformin). Both pregnancies were complicated by severe cervical incompetence, leading to the preterm birth of a healthy newborn in one case, but to a second trimester-abortion in the other. WRN-mutated fibroblasts showed oxidative stress, increased lamin B1 expression, nuclear dysmorphies and premature senescence.ConclusionsWe show here for the first time that partial lipodystrophy with severe insulin resistance can reveal WRN-linked premature aging syndrome. Increased expression of lamin B1 with altered lamina architecture observed in WRN-mutated fibroblasts could contribute to premature cellular senescence. Primary alterations in DNA replication and/or repair should be considered as possible causes of lipodystrophic syndromes.

Congenital generalized lipodystrophies—new insights into metabolic dysfunction

“…[12][13][14][15] By contrast, the other types of lipodystrophy-mandibuloacral dysplasia, autoinflammatory lipodystrophy, progeroid syndromes associated lipodystrophy, SHORT syndrome associated lipodystrophy and Keppen-Lubinsky syndrome associ ated lipodystrophy-are extremely rare and in total each subtype has been reported in no more than 30 patients (Box 1). 10,11,[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] However, FPLD has autosomal dominant inheritance and some patients with subtle loss of fat from the extremities might not receive an accurate diagnosis; therefore, the prevalence of this lipodystrophy might be higher than is reported. CGL has the most extreme pheno type with loss of nearly all the body fat at birth ( Figure 1) and early development of metabolic complications in childhood.…”

Current Diagnosis, Treatment and Clinical Challenges in the Management of Lipodystrophy Syndromes in Children and Young People

“…Lipodystrophy is a part of the clinical picture in many progeroid syndromes (1,47,48). There are also several other complex syndromes associated with lipodystrophy (1).…”

Stem cell aging in adult progeria

“…Adult WS patients mostly develop type 2 diabetes mellitus. Antidiabetic drugs like metformin, biguanide, and thiazolidinediones have been reported to improve insulin sensitivity in WS patients [ 75 – 77 ]. In addition to improve diabetes, metformin plays a second role in extending lifespan, as shown in animal models and clinical trials [ 78 , 79 ].…”