Comprehensive overview of disease models for Wolfram syndrome: toward effective treatments.

Wolfram syndrome (OMIM 222300) is a rare autosomal recessive disease with a devastating array of symptoms, including diabetes mellitus, optic nerve atrophy, diabetes insipidus, hearing loss, and neurological dysfunction. The discovery of the causative gene, WFS1, has propelled research on this disease. However, a comprehensive understanding of the function of WFS1 remains unknown, making the development of effective treatment a pressing challenge. To bridge these knowledge gaps, disease models for Wolfram syndrome are indispensable, and understanding the characteristics of each model is critical. This review will provide a summary of the current knowledge regarding WFS1 function and offer a comprehensive overview of established disease models for Wolfram syndrome, covering animal models such as mice, rats, flies, and zebrafish, along with induced pluripotent stem cell (iPSC)-derived human cellular models. These models replicate key aspects of Wolfram syndrome, contributing to a deeper understanding of its pathogenesis and providing a platform for discovering potential therapeutic approaches.

[Advances in diagnosis and treatment of Wolfram syndrome and related molecular mechanism].

Wolfram syndrome is a rare genetic spectrum disorder characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness, accompanied by other variable clinical manifestations. At present, the prognosis of this syndrome is very poor, the specific molecular mechanism is not clear, effective treatments are lacking to delay, prevent or reverse the development of Wolfram syndrome, and many patients die prematurely due to severe neurological dysfunction. This increases the urgency of the research on the pathogenic molecular mechanism related to Wolfram syndrome and the development of new therapies. This article summarizes the research progress on the pathogenic molecular mechanism and treatment status of Wolfram syndrome, in order to provide reference for the further mechanism research, prevention and treatment of Wolfram syndrome.

[Genetic protocol in primary care for rare diseases: Wolfram syndrome as a prototype]. / Protocolo genético en Atención Primaria para enfermedades raras: el síndrome de Wolfram como prototipo.

Rare diseases, despite their individual low frequency, affect 7% of the population all combined. Consequently, every primary care practitioner (PCP) will have several of these patients under his care. 80% of rare diseases are genetically determined, which makes genetic counseling fundamental in these cases. The follow-up of patients with Wolfram syndrome (WS) can be used to design a protocol to support these patients, with the participation of researchers and healthcare professionals specialized in WS, the patients themselves and their familial environment. This protocol can be suitable for the diagnosis and management of other diseases as well. The main steps of every genetic clinical procedure are developed in this article, emphasizing the role of PCP in supporting patients and their families and in transmitting genetic information in a comprehensible manner.

Wolfram syndrome, a rare neurodegenerative disease: from pathogenesis to future treatment perspectives.

BACKGROUND: Wolfram syndrome (WS), a rare genetic disorder, is considered the best prototype of endoplasmic reticulum (ER) diseases. Classical WS features are childhood-onset diabetes mellitus, optic atrophy, deafness, diabetes insipidus, neurological signs, and other abnormalities. Two causative genes (WFS1 and WFS2) have been identified. The transmission of the disease takes place in an autosomal recessive mode but autosomal dominant mutations responsible for WS-related disorders have been described. Prognosis is poor, death occurs at the median age of 39 years with a major cause represented by respiratory failure as a consequence of brain stem atrophy and neurodegeneration. The aim of this narrative review is to focus on etiology, pathogenesis and natural history of WS for an adequate patient management and for the discussion of future therapeutic interventions. MAIN BODY: WS requires a multidisciplinary approach in order to be successfully treated. A prompt diagnosis decreases morbidity and mortality through prevention and treatment of complications. Being a monogenic pathology, WS represents a perfect model to study the mechanisms of ER stress and how this condition leads to cell death, in comparison with other prevalent diseases in which multiple factors interact to produce the disease manifestations. WS is also an important disease prototype to identify drugs and molecules associated with ER homeostasis. Evidence indicates that specific metabolic diseases (type 1 and type 2 diabetes), neurodegenerative diseases, atherosclerosis, inflammatory pathologies and also cancer are closely related to ER dysfunction. CONCLUSIONS: Therapeutic strategies in WS are based on drug repurposing (i.e., investigation of approved drugs for novel therapeutic indications) with the aim to stop the progression of the disease by reducing the endoplasmic reticulum stress. An extensive understanding of WS from pathophysiology to therapy is fundamental and more studies are necessary to better manage this devastating disease and guarantee the patients a better quality of life and longer life expectancy.

A calcium-dependent protease as a potential therapeutic target for Wolfram syndrome.

Wolfram syndrome is a genetic disorder characterized by diabetes and neurodegeneration and considered as an endoplasmic reticulum (ER) disease. Despite the underlying importance of ER dysfunction in Wolfram syndrome and the identification of two causative genes, Wolfram syndrome 1 (WFS1) and Wolfram syndrome 2 (WFS2), a molecular mechanism linking the ER to death of neurons and ß cells has not been elucidated. Here we implicate calpain 2 in the mechanism of cell death in Wolfram syndrome. Calpain 2 is negatively regulated by WFS2, and elevated activation of calpain 2 by WFS2-knockdown correlates with cell death. Calpain activation is also induced by high cytosolic calcium mediated by the loss of function of WFS1. Calpain hyperactivation is observed in the WFS1 knockout mouse as well as in neural progenitor cells derived from induced pluripotent stem (iPS) cells of Wolfram syndrome patients. A small-scale small-molecule screen targeting ER calcium homeostasis reveals that dantrolene can prevent cell death in neural progenitor cells derived from Wolfram syndrome iPS cells. Our results demonstrate that calpain and the pathway leading its activation provides potential therapeutic targets for Wolfram syndrome and other ER diseases.

Wolfram Syndrome: Diagnosis, Management, and Treatment.

Wolfram syndrome is a rare genetic disorder characterized by juvenile-onset diabetes mellitus, diabetes insipidus, optic nerve atrophy, hearing loss, and neurodegeneration. Although there are currently no effective treatments that can delay or reverse the progression of Wolfram syndrome, the use of careful clinical monitoring and supportive care can help relieve the suffering of patients and improve their quality of life. The prognosis of this syndrome is currently poor, and many patients die prematurely with severe neurological disabilities, raising the urgency for developing novel treatments for Wolfram syndrome. In this article, we describe natural history and etiology, provide recommendations for diagnosis and clinical management, and introduce new treatments for Wolfram syndrome.

A Pair of Siblings With Wolfram Syndrome: A Review of the Literature and Treatment Options.

Wolfram syndrome (WS) is a rare genetic disorder typically characterized by juvenile onset diabetes mellitus, optic atrophy, hearing loss, diabetes insipidus, and neurodegeneration. There would be a high index of clinical suspicion for WS when clinical manifestations of type 1 diabetes and optic atrophy present together. Genetic analysis is often required to confirm the diagnosis. We describe a pair of Chinese siblings diagnosed with WS at ages 20 and 24 years, respectively. DNA sequencing of the WFS1 gene which encodes for Wolframin ER Transmembrane Glycoprotein identified a heterozygous nonsense variant NM_006005.3: c.1999C>T p.(Gln667*) and a heterozygous missense variant c.2170C>T p.(Pro724Ser) in exon 8 of the gene for both siblings. There is no curative treatment for WS and management of this debilitating disease is aimed at treating individual clinical manifestations, slowing disease progression, and improving quality of life. Treatment with liraglutide, a glucagon-like-peptide-1 receptor agonist, and tauroursodeoxycholic acid was started for the younger sibling, the proband. There was reduction in insulin requirements and improvement in glycemic control. The other sibling was not offered liraglutide due to her complex treatment regimen for end-organ failure. Genetic testing is a valuable tool to detect WS early to allow precise and prompt diagnosis, thereby facilitating the coordinated care from a multidisciplinary team of clinicians.

Clinical management and obstetric outcome in WFS1 Wolfram syndrome spectrum disorder: A case report and literature review.

OBJECTIVE: Wolfram Syndrome (WS) is a rare autosomal recessive neurodegenerative disorder caused by mutations in WFS1 or CISD2 (WFS2). We present a rare case report of pregnancy with WFS1 spectrum disorder (WFS1-SD) in our hospital and reviewed literature to provide the management of pregnancy in these patients through multi-disciplinary cooperation. CASE REPORT: A 31-year-old (gravida 6, para 1) woman with WFS1-SD conceived naturally. During the pregnancy, she adjusted insulin intermittently to control blood glucose and monitored intraocular pressure changes under the guidance of doctors without any complications. Cesarean section was delivered at 37+4 weeks of gestation due to breech position and uterine scar and the neonatal weight was 3200 g. Apgar score 10 at 1 min, 10 at 5-min and 10 at 10 min, respectively. This rare case had a good maternal and infant outcome under multidisciplinary management. CONCLUSION: WS is an extremely rare disease. Limited information is available on the impact and management of WS on maternal physiologic adaptation and fetal outcome. This case provide a guide for clinicians to raise awareness of this rare disease and strengthen the management of pregnancy in these patients.

Metabolic Treatment of Wolfram Syndrome.

Wolfram Syndrome (WS) is a very rare genetic disorder characterized by several symptoms that occur from childhood to adulthood. Usually, the first clinical sign is non-autoimmune diabetes even if other clinical features (optic subatrophy, neurosensorial deafness, diabetes insipidus) may be present in an early state and may be diagnosed after diabetes' onset. Prognosis is poor, and the death occurs at the median age of 39 years as a consequence of progressive respiratory impairment, secondary to brain atrophy and neurological failure. The aim of this paper is the description of the metabolic treatment of the WS. We reported the experience of long treatment in patients with this syndrome diagnosed in pediatric age and followed also in adult age. It is known that there is a correlation between metabolic control of diabetes, the onset of other associated symptoms, and the progression of the neurodegenerative alterations. Therefore, a multidisciplinary approach is necessary in order to prevent, treat and carefully monitor all the comorbidities that may occur. An extensive understanding of WS from pathophysiology to novel possible therapy is fundamental and further studies are needed to better manage this devastating disease and to guarantee to patients a better quality of life and a longer life expectancy.

Wolfram Syndrome 1: From Genetics to Therapy.

Wolfram syndrome 1 (WS1) is a rare neurodegenerative disease transmitted in an autosomal recessive mode. It is characterized by diabetes insipidus (DI), diabetes mellitus (DM), optic atrophy (OA), and sensorineural hearing loss (D) (DIDMOAD). The clinical picture may be complicated by other symptoms, such as urinary tract, endocrinological, psychiatric, and neurological abnormalities. WS1 is caused by mutations in the WFS1 gene located on chromosome 4p16 that encodes a transmembrane protein named wolframin. Many studies have shown that wolframin regulates some mechanisms of ER calcium homeostasis and therefore plays a role in cellular apoptosis. More than 200 mutations are responsible for WS1. However, abnormal phenotypes of WS with or without DM, inherited in an autosomal dominant mode and associated with one or more WFS1 mutations, have been found. Furthermore, recessive Wolfram-like disease without DM has been described. The prognosis of WS1 is poor, and the death occurs prematurely. Although there are no therapies that can slow or stop WS1, a careful clinical monitoring can help patients during the rapid progression of the disease, thus improving their quality of life. In this review, we describe natural history and etiology of WS1 and suggest criteria for a most pertinent approach to the diagnosis and clinical follow up. We also describe the hallmarks of new therapies for WS1.

Collaboration for rare diabetes: understanding new treatment options for Wolfram syndrome.

BACKGROUND: Wolfram Syndrome is a very rare genetic disease causing diabetes mellitus, blindness, deafness, diabetes insipidus, and progressive brainstem degeneration. Neurologic symptoms of affected patients include ataxia, sleep apnea, loss of bladder control, dysphagia, loss of taste, and accompanying psychiatric symptoms as a sign of progressive neurodegeneration. Its genetic cause is mainly biallelic mutations of the Wolframin endoplasmatic reticulum transmembrane glycoprotein gene Wfs1. These result in increased ER stress, which in turn induces apoptosis and leads to the depletion of the corresponding cells and a loss of their physiological functions. Though diabetes mellitus is mostly treated by insulin, there is still no proven cure for the disease in general. It leads to premature death in affected individuals-usually within the 4th decade of live. CURRENT RESEARCH AND TREATMENT TRIALS: Clinical studies are currently being conducted at various locations worldwide to test a therapy for the disease using various approaches. POTENTAIL OF VIRTUAL NETOWRKING: As rare diseases in general represent a major challenge for individual clinicians and researchers due to the rarity of diagnosis, the lack of evidence and of value of existing research, international cooperation, coordination and networking leading to an alignment of different stakeholders is necessary to support patients and increase knowledge about these diseases, like wolfram syndrome. CONCLUSION: ENDO-ERN and EURRECA are two EU-funded networks that aim to promote knowledge sharing, education and research on rare endocrine diseases.

[Clinical characteristics of Wolfram syndrome].

OBJECTIVE: Wolfram syndrome (WFS) is a rare, autosomal recessive inherited disease characterized by various clinical manifestations. The aim of this study was to investigate clinical characteristics of WFS. METHODS: One case of WFS was reported. Combined with the clinical data of 8 cases of WFS which had been reported in China between 1994 and 2007, the clinical characteristics of WFS were reviewed. RESULTS: Insulin-dependent diabetes mellitus as the earliest manifestation was found in all of the 9 patients, with a median onset age of 5.0 years. Optic atrophy occurred in 8 patients (onset age: 8.5 years), diabetes insipidus in 7 patients (onset age: 8.5 years) and deafness in 7 patients (onset age: 9.8 years). Short stature was found in 6 patients and hydroureteronephrosis in 4 patients. CONCLUSIONS: Insulin-dependent diabetes mellitus was the first presentation in children with WFS. Optic atrophy, diabetes insipidus and deafness were common complications, with a various onset age.

Current Landscape of Treatments for Wolfram Syndrome.

Wolfram syndrome is a rare genetic spectrum disorder characterized by insulin-dependent diabetes mellitus, optic nerve atrophy, and progressive neurodegeneration, and ranges from mild to severe clinical symptoms. There is currently no treatment to delay, halt, or reverse the progression of Wolfram syndrome, raising the urgency for innovative therapeutics for this disease. Here, we summarize our vision for developing novel treatment strategies and achieving a cure for Wolfram-syndrome-spectrum disorder.

[Hereditary optic neuropathies in pediatric ophthalmology]. / Neuropathies optiques héréditaires en ophtalmo-pédiatrie.

INTRODUCTION: Hereditary optic neuropathies (HON) often begin in adulthood. However, some of them can have an early onset. These may have specific clinical features and natural histories. PATIENTS AND METHODS: Retrospective study of HON patients with onset before the age of 14 years seen in a referral center. In addition to the age of onset, we evaluated the genetic etiology, visual acuity at 15 years, last best corrected visual acuity, optic disc appearance, visual field and extra-ophthalmological manifestations. RESULTS: Forty-four patients (16 women) were included; i.e. 27.8% of all patients followed for HON. The mean age of onset was 8.5±3.3 years, with an onset earlier than 3 years in 5 patients. An etiology was not found in 8 patients. Of the remaining 36 patients, 12 had Leber's hereditary optic neuropathy (LHON), 11 had dominant optic atrophy, 12 had WS/WS-like syndrome, 2 had recessive optic atrophy and 1 had spastic paraplegia type 7. For 78 eyes of 40 patients (mean age 26.9±14.5 years), the mean last visual acuity was 0.80±0.33 LogMAR, with differences according to genetic forms. Visual acuity was less than or equal to counting fingers for 7 eyes (29.1%) of 4 WS/WS-like patients and one LHON patient. CONCLUSION: Early onset NOH are not unusual. Their visual prognosis is as severe as adult onset NOH, with variations depending on the underlying genetic causes.

Advances in diagnosis and treatment of Wolfram syndrome and related molecular mechanism / 中华预防医学杂志

Wolfram syndrome is a rare genetic spectrum disorder characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness, accompanied by other variable clinical manifestations. At present, the prognosis of this syndrome is very poor, the specific molecular mechanism is not clear, effective treatments are lacking to delay, prevent or reverse the development of Wolfram syndrome, and many patients die prematurely due to severe neurological dysfunction. This increases the urgency of the research on the pathogenic molecular mechanism related to Wolfram syndrome and the development of new therapies. This article summarizes the research progress on the pathogenic molecular mechanism and treatment status of Wolfram syndrome, in order to provide reference for the further mechanism research, prevention and treatment of Wolfram syndrome.

[Wolfram syndrome. Report of 3 cases]. / Le syndrome de Wolfram. A propos de 3 cas.

Wolfram's syndrome is an autosomal recessive neurodegenerative disease. The major manifestations consist of diabetes mellitus and bilateral optic atrophy and are sufficient to establish the diagnosis. Urinary manifestations constitute an integral part of the syndrome, as they are present in up to 62% of cases and represent one of the major causes of morbidity. Three cases allow emphasize the difficulty of treatment, which is essentially symptomatic, and largely guided by the results of the various complementary investigations, especially urodynamic assessment. Although the causes of this syndrome are multifactorial and complex, it appears that the urinary lesions are at least temporarily improved by correction of excessive bladder pressure.