Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 396
Filtrar
1.
bioRxiv ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39229169

RESUMEN

Iron-sulfur clusters (ISCs) are cell-essential cofactors present in ∼60 proteins including subunits of OXPHOS complexes I-III, DNA polymerases, and iron-sensing proteins. Dysfunctions in ISC biosynthesis are associated with anemias, neurodegenerative disorders, and metabolic diseases. To assess consequences of acute ISC inhibition in a whole body setting, we developed a mouse model in which key ISC biosynthetic enzyme NFS1 can be acutely and reversibly suppressed. Contrary to in vitro ISC inhibition and pharmacological OXPHOS suppression, global NFS1 inhibition rapidly enhances lipid utilization and decreases adiposity without affecting caloric intake and physical activity. ISC proteins decrease, including key proteins involved in OXPHOS (SDHB), lipoic acid synthesis (LIAS), and insulin mRNA processing (CDKAL1), causing acute metabolic inflexibility. Age-related metabolic changes decelerate loss of adiposity substantially prolonged survival of mice with NFS1 inhibition. Thus, the observation that ISC metabolism impacts organismal fuel choice will aid in understanding the mechanisms underlying ISC diseases with increased risk for diabetes. Highlights: Acute ISC inhibition leads to rapid loss of adiposity in miceMulti-metabolic pathway disruption upon ISC deficiency blocks energy storageNfs1 inhibition induces glucose dyshomeostasis due to ISC deficiency in ß-cellsEnergy distress caused by inhibition of ISC synthesis is attenuated in aged mice.

2.
Acta Biomater ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39236796

RESUMEN

In vivo molecular imaging tools hold immense potential to drive transformative breakthroughs by enabling researchers to visualize cellular and molecular interactions in real-time and/or at high resolution. These advancements will facilitate a deeper understanding of fundamental biological processes and their dysregulation in disease states. Here, we develop and characterize a self-assembling protein nanomicelle called collagen type I binding - thermoresponsive assembled protein (Col1-TRAP) that binds tightly to type I collagen in vitro with nanomolar affinity. For ex vivo visualization, Col1-TRAP is labeled with a near-infrared fluorescent dye (NIR-Col1-TRAP). Both Col1-TRAP and NIR-Col1-TRAP display approximately a 3.8-fold greater binding to type I collagen compared to TRAP when measured by surface plasmon resonance (SPR). We present a proof-of-concept study using NIR-Col1-TRAP to detect fibrotic type I collagen deposition ex vivo in the livers of mice with non-alcoholic steatohepatitis (NASH). We show that NIR-Col1-TRAP demonstrates significantly decreased plasma recirculation time as well as increased liver accumulation in the NASH mice compared to mice without disease over 4 hours. As a result, NIR-Col1-TRAP shows potential as an imaging probe for NASH with in vivo targeting performance after injection in mice. STATEMENT OF SIGNIFICANCE: Direct molecular imaging of fibrosis in NASH patients enables the diagnosis and monitoring of disease progression with greater specificity and resolution than do elastography-based methods or blood tests. In addition, protein-based imaging probes are more advantageous than alternatives due to their biodegradability and scalable biosynthesis. With the aid of computational modeling, we have designed a self-assembled protein micelle that binds to fibrillar and monomeric collagen in vitro. After the protein was labeled with near-infrared fluorescent dye, we injected the compound into mice fed on a NASH diet. NIR-Col1-TRAP clears from the serum faster in these mice compared to control mice, and accumulates significantly more in fibrotic livers.This work advances the development of targeted protein probes for in vivo fibrosis imaging.

3.
Atherosclerosis ; 3942024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39131441

RESUMEN

Background and aims: In hyperglycemia, inflammation, oxidative stress and aging, Damage Associated Molecular Patterns (DAMPs) accumulate in conditions such as atherosclerosis. Binding of DAMPs to receptors such as the receptor for advanced glycation end products (RAGE) activates signal transduction cascades that contribute to cellular stress. The cytoplasmic domain (tail) of RAGE (ctRAGE) binds to the formin Diaphanous1 (DIAPH1), which is important for RAGE signaling. This Review will detail the evidence linking the RAGE/DIAPH1 signaling pathway to atherosclerosis and envisages future therapeutic opportunities from the "inside-out" point of view in affected cells. Methods: PubMed was searched using a variety of search terms, including "receptor for advanced glycation end products" along with various combinations including "and atherosclerosis," "soluble RAGE and atherosclerosis," "statins and RAGE," "PPAR and RAGE" and "SGLT2 inhibitor and RAGE." Results: In non-diabetic and diabetic mice, antagonism or global deletion of Ager (the gene encoding RAGE) retards progression and accelerates regression of atherosclerosis. Global deletion of Diaph1 in mice devoid of the low density lipoprotein receptor (Ldlr) significantly attenuates atherosclerosis; mice devoid of both Diaph1 and Ldlr display significantly lower plasma and liver concentrations of cholesterol and triglyceride compared to mice devoid of Ldlr. Associations between RAGE pathway and human atherosclerosis have been identified based on relationships between plasma/serum concentrations of RAGE ligands, soluble RAGEs and atherosclerosis. Conclusions: Efforts to target RAGE/DIAPH1 signaling through a small molecule antagonist therapeutic strategy hold promise to quell accelerated atherosclerosis in diabetes and in other forms of cardiovascular disease.


Asunto(s)
Aterosclerosis , Forminas , Receptor para Productos Finales de Glicación Avanzada , Transducción de Señal , Aterosclerosis/metabolismo , Animales , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Humanos , Forminas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Ratones
4.
BMJ Open ; 14(8): e081201, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39181563

RESUMEN

PURPOSE: We developed a comprehensive sleeve gastrectomy (SG) weight loss study cohort and biorepository to uncover mechanisms, biomarkers and predictive factors of weight loss, weight maintenance and amelioration of obesity-related comorbidities. For this purpose, we collected psychosocial, anthropometric, clinical data and a variety of samples pre-surgery, intraoperatively and 1.5, 3, 12 and 24 months post-surgery. For longer-term assessment, the collection of psychosocial and anthropometric data was extended to 10 years. Here, we present in-depth characterisation of the cohort and detailed overview of study procedures as a foundation for future analyses. PARTICIPANTS: We consented 647 participants between June 2017 and March 2020 from two bariatric surgery clinics in New York City-one major urban hospital and one private hospital. Of 355 participants who provided baseline data, 300 underwent SG. Of these, 79% are females with an average age of 38 years, 68% are Hispanic, 20% are non-Hispanic Black and 11% are non-Hispanic White. FINDINGS TO DATE: We collected intraoperative adipose and stomach tissues from 282 patients and biosamples (blood, urine, saliva, stool) from 245 patients at 1.5 months, 238 at 3 month, 218 at 12 months and 180 at 24 months post-surgery. We are currently collecting anthropometric and psychosocial data annually until 10 years post-surgery. Data analysis is currently underway. FUTURE PLANS: Our future research will explore the variability in weight loss outcomes observed in our cohort, particularly among Black and Hispanic patients in comparison to their White counterparts. We will identify social determinants of health, metabolic factors and other variables that may predict weight loss success, weight maintenance and remission of obesity-related comorbidities. Additionally, we plan to leverage our biorepository for collaborative research studies. We will complete long-term follow-up data by December 2031. We plan to apply for funding to expand biosample collection through year 10 to provide insights into the mechanisms of long-term weight maintenance.


Asunto(s)
Gastrectomía , Obesidad Mórbida , Pérdida de Peso , Humanos , Femenino , Adulto , Gastrectomía/métodos , Masculino , Obesidad Mórbida/cirugía , Estudios Longitudinales , Persona de Mediana Edad , Cirugía Bariátrica/métodos , Estados Unidos , Proyectos de Investigación , Estudios de Cohortes
8.
BMC Musculoskelet Disord ; 25(1): 391, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762469

RESUMEN

BACKGROUND: Pain is common in individuals with cerebral palsy (CP) and the most reported pain site is the foot/lower leg. We analyzed the prevalence of pain in the foot/lower leg and the associations with age, sex, gross motor function, and clinical findings in individuals with CP. METHOD: This was a cross-sectional register-study, based on data reported to the Swedish Cerebral Palsy Follow-up Program (CPUP). All participants in CPUP, four years-of-age or older, were included. Pearson chi-square tests and logistic regression were used to analyze the prevalence and degree of pain in the foot/lower leg. RESULTS: In total, 5,122 individuals were included from the CPUP database: 58% were males and 66% were under 18 years-of-age. Overall, 1,077 (21%) reported pain in the foot/lower leg. The odds ratios (ORs) of pain were higher in females (OR 1.31, 95% confidence interval (CI) 1.13-1.53), individuals who could ambulate (Gross Motor Function Classification System Level I (OR 1.84, CI 1.32-2.57) and II (OR 2.01, CI 1.46-2.79) compared to level V), and in individuals with decreased range of motion of the ankle (dorsiflexion 1-10 degrees (OR 1.43, CI 1.13-1.83) and ≤ 0 degrees (OR 1.46, CI 1.10-1.93) compared to ≥ 20 degrees). With increasing age the OR of pain increased (OR 1.02, CI 1.01-1.03) as well as the reported pain intensity (p < 0.001). CONCLUSIONS: Pain in the foot and lower leg appears to be a significant problem in individuals with CP, particularly in those who walk. As with pain in general in this population, both pain intensity and frequency increase with age. The odds of pain in the foot and lower leg were increased in individuals with limited dorsiflexion of the ankle. Given the cross-sectional design causality cannot be inferred and it is unknown if pain causes decreased range of motion of the ankle or if decreased range of motion causes pain. Further research is needed on causal pathways and importantly on prevention.


Asunto(s)
Parálisis Cerebral , Pierna , Sistema de Registros , Humanos , Parálisis Cerebral/epidemiología , Parálisis Cerebral/complicaciones , Parálisis Cerebral/fisiopatología , Masculino , Femenino , Estudios Transversales , Adulto , Adolescente , Niño , Adulto Joven , Suecia/epidemiología , Preescolar , Prevalencia , Pie/fisiopatología , Persona de Mediana Edad , Dolor/epidemiología , Dolor/diagnóstico , Dolor/etiología , Dimensión del Dolor
9.
Disabil Health J ; 17(3): 101627, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38637232

RESUMEN

BACKGROUND: Thanks to improved medical care, individuals with spina bifida (SB) live well into adulthood and go through the process of reproductive maturation and the development of sexual desires. However, access to reproductive counselling and contraceptive use has been reported to be lower for women with physical and intellectual disabilities compared to the general population. OBJECTIVE: We investigated oral contraceptive use in women with SB, residing in Sweden and how use varies based on the level of lesion and demographic factors. METHODS: This was a population-based case-control study using annual data from national registers from 2006 to 2015. The sample consisted of 7045 women aged 15-49 years, of which 1173 had a diagnosis of SB. χ2 tests and logistic regression were used to investigate the study objective. RESULTS: The rate of oral contraceptive use in women with SB was 24.6 % compared to 34.5 % among the general population. After adjusting for potential confounders women with SB were found to have a lower probability of using oral contraceptives (OR 0.63 95 % CI 0.56-0.71) compared to women without SB. Among women with SB, those with diagnoses Q05.8 (Sacral SB without hydrocephalus) and Q05.9 (SB unspecified) had a higher likelihood of using oral contraceptives compared to other Q05 diagnoses. CONCLUSION: Women with SB had a lower likelihood of being on oral contraceptives compared to the control group. Further research should investigate if the lower use indicates that oral contraceptives are not an inappropriate method of contraception for women with SB.


Asunto(s)
Conducta Anticonceptiva , Anticonceptivos Orales , Personas con Discapacidad , Disrafia Espinal , Humanos , Femenino , Suecia/epidemiología , Disrafia Espinal/epidemiología , Adulto , Adolescente , Estudios de Casos y Controles , Adulto Joven , Persona de Mediana Edad , Conducta Anticonceptiva/estadística & datos numéricos , Personas con Discapacidad/estadística & datos numéricos , Modelos Logísticos , Sistema de Registros , Anticoncepción/estadística & datos numéricos , Anticoncepción/métodos
10.
Proc Natl Acad Sci U S A ; 121(15): e2400675121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38564634

RESUMEN

Atherosclerosis is fueled by a failure to resolve lipid-driven inflammation within the vasculature that drives plaque formation. Therapeutic approaches to reverse atherosclerotic inflammation are needed to address the rising global burden of cardiovascular disease (CVD). Recently, metabolites have gained attention for their immunomodulatory properties, including itaconate, which is generated from the tricarboxylic acid-intermediate cis-aconitate by the enzyme Immune Responsive Gene 1 (IRG1/ACOD1). Here, we tested the therapeutic potential of the IRG1-itaconate axis for human atherosclerosis. Using single-cell RNA sequencing (scRNA-seq), we found that IRG1 is up-regulated in human coronary atherosclerotic lesions compared to patient-matched healthy vasculature, and in mouse models of atherosclerosis, where it is primarily expressed by plaque monocytes, macrophages, and neutrophils. Global or hematopoietic Irg1-deficiency in mice increases atherosclerosis burden, plaque macrophage and lipid content, and expression of the proatherosclerotic cytokine interleukin (IL)-1ß. Mechanistically, absence of Irg1 increased macrophage lipid accumulation, and accelerated inflammation via increased neutrophil extracellular trap (NET) formation and NET-priming of the NLRP3-inflammasome in macrophages, resulting in increased IL-1ß release. Conversely, supplementation of the Irg1-itaconate axis using 4-octyl itaconate (4-OI) beneficially remodeled advanced plaques and reduced lesional IL-1ß levels in mice. To investigate the effects of 4-OI in humans, we leveraged an ex vivo systems-immunology approach for CVD drug discovery. Using CyTOF and scRNA-seq of peripheral blood mononuclear cells treated with plasma from CVD patients, we showed that 4-OI attenuates proinflammatory phospho-signaling and mediates anti-inflammatory rewiring of macrophage populations. Our data highlight the relevance of pursuing IRG1-itaconate axis supplementation as a therapeutic approach for atherosclerosis in humans.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Animales , Humanos , Ratones , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/genética , Colesterol , Inflamación/metabolismo , Leucocitos Mononucleares/metabolismo , Lípidos , Placa Aterosclerótica/tratamiento farmacológico , Succinatos/metabolismo
11.
Obes Sci Pract ; 10(1): e729, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38187121

RESUMEN

Objective: HbA1c is an insensitive marker for assessing real-time dysglycemia in obesity. This study investigated whether 1-h plasma glucose level (1-h PG) ≥155 mg/dL (8.6 mmol/L) during an oral glucose tolerance test (OGTT) and continuous glucose monitoring (CGM) measurement of glucose variability (GV) better reflected dysglycemia than HbA1c after weight loss from metabolic and bariatric surgery. Methods: This was a prospective cohort study of 10 participants with type 2 diabetes compared with 11 participants with non-diabetes undergoing sleeve gastrectomy (SG). At each research visit; before SG, and 6 weeks and 6 months post-SG, body weight, fasting lipid levels, and PG and insulin concentrations during an OGTT were analyzed. Mean amplitude of glycemic excursions (MAGE), a CGM-derived GV index, was analyzed. Results: The 1-h PG correlated with insulin resistance markers, triglyceride/HDL ratio and triglyceride glucose index in both groups before surgery. At 6 months, SG caused 22% weight loss in both groups. Despite a reduction in HbA1c by 3.0 ± 1.3% in the diabetes group (p < 0.01), 1-h PG, and MAGE remained elevated, and the oral disposition index, which represents pancreatic ß-cell function, remained reduced in the diabetes group when compared to the non-diabetes group. Conclusions: Elevation of GV markers and reduced disposition index following SG-induced weight loss in the diabetes group underscores persistent ß-cell dysfunction and the potential residual risk of diabetes complications.

13.
J Card Fail ; 30(4): 580-591, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37625581

RESUMEN

BACKGROUND: Venous congestion (VC) is a hallmark of symptomatic heart failure (HF) requiring hospitalization; however, its role in the pathogenesis of HF progression remains unclear. We investigated whether peripheral VC exacerbates inflammation, oxidative stress and neurohormonal and endothelial cell (EC) activation in patients with HF with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Two matched groups of patients with HFrEF and with no peripheral VC vs without recent HF hospitalization were studied. We modeled peripheral VC by inflating a cuff around the dominant arm, targeting ∼ 30 mmHg increase in venous pressure (venous stress test [VST]). Blood and ECs were sampled before and after 90 minutes of VST. We studied 44 patients (age 53 ± 12 years, 32% female). Circulating endothelin-1, tumor necrosis factor-α, interleukin-6, isoprostane, angiotensin II (ang-2), angiopoietin-2, vascular cell adhesion molecule-1, and CD146 significantly increased after the VST. Enhanced endothelin-1 and angiopoietin-2 responses to the VST were present in patients with vs without recent hospitalization and were prospectively associated with incident HF-related events; 6698 messenger ribonucleic acid (mRNA probe sets were differentially expressed in ECs after VST. CONCLUSIONS: Experimental VC exacerbates inflammation, oxidative stress, neurohormonal and EC activation and promotes unfavorable transcriptome remodeling in ECs of patients with HFrEF. A distinct biological sensitivity to VC appears to be associated with high risk for HF progression.


Asunto(s)
Insuficiencia Cardíaca Sistólica , Insuficiencia Cardíaca , Hiperemia , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Masculino , Angiopoyetina 2/metabolismo , Endotelina-1 , Volumen Sistólico , Inflamación , Células Endoteliales , Estrés Oxidativo
14.
J Sch Health ; 94(2): 105-116, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37853427

RESUMEN

BACKGROUND: Students with intellectual and developmental disabilities (IDD) and the staff who support them were largely in-person during the 2021-2022 school year, despite their continued vulnerability to infection with SARS-CoV-2. This qualitative study aimed to understand continued perceptions of weekly SARS-CoV-2 screening testing of students and staff amidst increased availability of vaccinations. METHODS: Twenty-three focus groups were held with school staff and parents of children with IDD to examine the perceptions of COVID-19 during the 2021-2022 school year. Responses were analyzed using a directed thematic content analysis approach. RESULTS: Four principal themes were identified: strengths and opportunities of school- and district-level mitigation policies; experience at school with the return to in-person learning; facilitators and barriers to participation in SARS-CoV-2 screening testing; and perceptions of SARS-CoV-2 testing in light of vaccine availability. IMPLICATIONS FOR SCHOOL HEALTH POLICY, PRACTICE, AND EQUITY: Despite the increased availability of vaccines, school staff and families agreed that saliva-based SARS-CoV-2 screening testing helped increase comfort with in-person learning as long as the virus was present in the community. CONCLUSION: To keep children with IDD in school during the pandemic, families found SARS-CoV-2 screening testing important. Clearly communicating school policies and mitigation strategies facilitated peace of mind and confidence in the school district.


Asunto(s)
COVID-19 , Niño , Humanos , COVID-19/epidemiología , Prueba de COVID-19 , Estudios de Seguimiento , SARS-CoV-2 , Política de Salud
15.
PLoS Biol ; 21(12): e3002448, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38048365

RESUMEN

Globally, obesity is on the rise. Research over the past 20 years has highlighted the far-reaching multisystem complications of obesity, but a better understanding of its complex pathogenesis is needed to identify safe and lasting solutions.


Asunto(s)
Obesidad , Humanos , Obesidad/epidemiología
16.
J Pediatr Rehabil Med ; 16(4): 657-663, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143399

RESUMEN

PURPOSE: This project aimed to launch an international learning community to guide the development of a spina bifida (SB) curriculum for global health trainees. METHODS: Using a descriptive study design, a convenience sample of SB curricula were identified in 2022-23 by members of the Spina Bifida World Congress Outreach Committee and evaluated during a series of monthly Zoom calls to discuss SB education in a global health context. Participants included (1) leadership from the ReachAnother Foundation, (2) invited panelists from the Spina Bifida World Congress Global Health Symposium, and (3) global health students and preceptors. Education initiatives in Ethiopia, Sweden, Argentina, Ecuador, and the United States were evaluated vis-à-vis format and content. RESULTS: All of the education initiatives referenced the framework of the World Health Organization International Classification of Functioning, Disability and Health. Formats varied and included both virtual and interactive workshops, print materials, videos, and guides for small group discussion. Content addressed four domains: Folate Prevention, Neurosurgical Training, After Care, and Data Collection. A multidisciplinary approach, partnerships with families, and workforce pipeline training were identified as guiding themes for educating the next generation of SB researchers and clinicians in global health settings. CONCLUSION: The Spina Bifida Global Learning Collaborative is a transnational group of advocates, clinicians, and investigators whose mission is the advancement of SB-related global health education. Lessons learned from the collaborative are being leveraged to develop a global health curriculum for learners, which may improve services for individuals with SB around the globe.


Asunto(s)
Disrafia Espinal , Humanos , Salud Global , Curriculum , Argentina , Suecia
17.
J Rehabil Med ; 55: jrm18244, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38010218

RESUMEN

OBJECTIVE: To analyse survival rates and causes of death in adults with spina bifida in Sweden compared with a matched control group. DESIGN AND METHODS: This population-based study included 11,900 adults born between 1950 and 1997. Three national Swedish registers were used to identify individuals with a diagnosis of spina bifida and a matched control group without spina bifida in the period 1990-2015. International Classification of Diseases codes were used to identify causes of death. Survival analysis was conducted and causes of death in the 2 groups were compared. RESULTS: There was a lower probability of survival for people with spina bifida in all age groups (p < 0.001) compared with the control group. The most prevalent causes of death in people with spina bifida were congenital, respiratory, nervous, cardiovascular, genitourinary, and injuries. People with spina bifida had a higher probability of dying from congenital (p < 0.001), respiratory (p = 0.002), genitourinary (p < 0.002), and nervous-related (p < 0.001) and lower probability of injury-related deaths (p < 0.001). CONCLUSION: Adults with spina bifida in Sweden have a lower survival rate compared with the general population, with the frequency of certain causes of death differing between the two groups. In order to reduce excess premature mortality, prevention and careful management of potentially fatal conditions are essential throughout a patient's lifespan.


Asunto(s)
Disrafia Espinal , Humanos , Adulto , Suecia/epidemiología , Estudios de Casos y Controles , Causas de Muerte , Proyectos de Investigación
18.
Lakartidningen ; 1202023 11 15.
Artículo en Sueco | MEDLINE | ID: mdl-37965934

RESUMEN

CPUP is a combined follow-up program and national quality registry for cerebral palsy (CP). Since its inception in southern Sweden in 1994, CPUP has expanded geographically to cover all of Sweden, and similar programs are used in several northern European countries. Over 95% of all children with CP in Sweden, and a growing proportion of adults, are followed according to CPUP. The content of CPUP has been developed to involve most professions working with CP. CPUP has led to significant medical improvements. As an example, the percentage of individuals developing hip dislocation has decreased from 10% to 0.5%. The program's strengths include its interdisciplinary collaboration, user involvement, and the ability to inform and improve the quality of care systematically. Nevertheless, challenges include the need for ongoing funding and support. CPUP's success exemplifies how national quality registers can integrate into healthcare, enabling a shift from reactive to proactive care.


Asunto(s)
Parálisis Cerebral , Luxación de la Cadera , Niño , Adulto , Humanos , Estudios de Seguimiento , Parálisis Cerebral/epidemiología , Parálisis Cerebral/terapia , Sistema de Registros , Suecia/epidemiología
19.
J Biol Chem ; 299(11): 105342, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37832872

RESUMEN

The diaphanous-related formin, Diaphanous 1 (DIAPH1), is required for the assembly of Filamentous (F)-actin structures. DIAPH1 is an intracellular effector of the receptor for advanced glycation end products (RAGE) and contributes to RAGE signaling and effects such as increased cell migration upon RAGE stimulation. Mutations in DIAPH1, including those in the basic "RRKR" motif of its autoregulatory domain, diaphanous autoinhibitory domain (DAD), are implicated in hearing loss, macrothrombocytopenia, and cardiovascular diseases. The solution structure of the complex between the N-terminal inhibitory domain, DID, and the C-terminal DAD, resolved by NMR spectroscopy shows only transient interactions between DID and the basic motif of DAD, resembling those found in encounter complexes. Cross-linking studies placed the RRKR motif into the negatively charged cavity of DID. Neutralizing the cavity resulted in a 5-fold decrease in the binding affinity and 4-fold decrease in the association rate constant of DAD for DID, indicating that the RRKR interactions with DID form a productive encounter complex. A DIAPH1 mutant containing a neutralized RRKR binding cavity shows excessive colocalization with actin and is unresponsive to RAGE stimulation. This is the first demonstration of a specific alteration of the surfaces responsible for productive encounter complexation with implications for human pathology.


Asunto(s)
Citoesqueleto de Actina , Actinas , Forminas , Humanos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Citoesqueleto/metabolismo , Forminas/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Transducción de Señal
20.
Nat Commun ; 14(1): 6900, 2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-37903764

RESUMEN

Inter-organelle contact and communication between mitochondria and sarco/endoplasmic reticulum (SR/ER) maintain cellular homeostasis and are profoundly disturbed during tissue ischemia. We tested the hypothesis that the formin Diaphanous-1 (DIAPH1), which regulates actin dynamics, signal transduction and metabolic functions, contributes to these processes. We demonstrate that DIAPH1 interacts directly with Mitofusin-2 (MFN2) to shorten mitochondria-SR/ER distance, thereby enhancing mitochondria-ER contact in cells including cardiomyocytes, endothelial cells and macrophages. Solution structure studies affirm the interaction between the Diaphanous Inhibitory Domain and the cytosolic GTPase domain of MFN2. In male rodent and human cardiomyocytes, DIAPH1-MFN2 interaction regulates mitochondrial turnover, mitophagy, and oxidative stress. Introduction of synthetic linker construct, which shorten the mitochondria-SR/ER distance, mitigated the molecular and functional benefits of DIAPH1 silencing in ischemia. This work establishes fundamental roles for DIAPH1-MFN2 interaction in the regulation of mitochondria-SR/ER contact networks. We propose that targeting pathways that regulate DIAPH1-MFN2 interactions may facilitate recovery from tissue ischemia.


Asunto(s)
Células Endoteliales , Mitocondrias , Humanos , Masculino , Retículo Endoplásmico/metabolismo , Células Endoteliales/metabolismo , Forminas/metabolismo , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , Isquemia/genética , Isquemia/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Transducción de Señal , Animales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA