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1.
bioRxiv ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38260661

RESUMO

Absent in Melanoma (AIM) 2 is a gene that is induced by interferon and acts as a cytosolic sensor for double-stranded (ds) DNA. It forms the AIM2 inflammasome, leading to the production of interleukin (IL)-1ß and IL-18. Our previous research demonstrated that mice lacking AIM2 exhibit spontaneous obesity, insulin resistance, and inflammation in adipose tissue. In this study, we aimed to explore the impact of AIM2 gene deletion on bone structure in adult and aged mice. Utilizing micro-computed tomography (micro-CT), we discovered that female mice lacking AIM2 showed an increase in the total cross-sectional area at 5 months of age, accompanied by an increase in cortical thickness in the mid-diaphysis of the femur at both 5 and 15 months of age. At 15 months of age, the cortical bone mineral density (BMD) significantly decreased in AIM2 null females compared to wild-type (WT) mice. In AIM2 null mice, both trabecular bone volume and BMD at the distal metaphysis of the femur significantly decreased at 5 and 15 months of age. Similarly, micro-CT analysis of the L4 vertebra revealed significant decreases in trabecular bone volume and BMD in aged AIM2 null females compared to WT mice. Histological examination of femurs from aged mice demonstrated increased bone marrow adiposity in AIM2 null mice, accompanied by a significant increase in CD45-/CD31-/Sca1+/Pdgfa+ adipose progenitor cells, and a decrease in the ratio of CD31-/CD31+ osteogenic progenitor cells, as determined by flow cytometry of bone marrow cells. Our findings suggest that AIM2 deficiency affects bone health by promoting adipogenesis in bone marrow cells and inducing a pro-inflammatory environment, potentially contributing to the decreased bone mineral density.

2.
bioRxiv ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38076995

RESUMO

The "Mlx" and "Myc" Networks share many common gene targets. Just as Myc's activity depends upon its heterodimerization with Max, the Mlx Network requires that the Max-like factor Mlx associate with the Myc-like factors MondoA or ChREBP. We show here that body-wide Mlx inactivation, like that of Myc, accelerates numerous aging-related phenotypes pertaining to body habitus and metabolism. The deregulation of numerous aging-related Myc target gene sets is also accelerated. Among other functions, these gene sets often regulate ribosomal and mitochondrial structure and function, genomic stability and aging. Whereas "MycKO" mice have an extended lifespan because of a lower cancer incidence, "MlxKO" mice have normal lifespans and a somewhat higher cancer incidence. Like Myc, Mlx, MondoA and ChREBP expression and that of their target genes, deteriorate with age in both mice and humans, underscoring the importance of life-long and balanced cross-talk between the two Networks to maintain normal aging.

3.
Curr Opin Pediatr ; 35(6): 703-709, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37811914

RESUMO

PURPOSE OF REVIEW: Pediatric solid organ transplant recipients are a unique and growing patient population who are at risk for metabolic bone disease both before and after transplantation. RECENT FINDINGS: The odds of sustaining a fracture in adulthood are significantly higher if an individual has sustained at least one childhood fracture, therefore, close monitoring before and after transplant is essential. Emerging data in patients with chronic kidney disease mineral and bone disorder (CKD-MBD) and hepatic osteodystrophy highlights the role of fibroblast growth factor 23 in the pathogenesis of metabolic bone disease in these conditions. While dual X-ray absorptiometry (DXA) is the most widely used imaging modality for assessment of bone mass in children, quantitative computer tomography (QCT) is an emerging modality, especially for patients with glucocorticoid-induced osteoporosis. SUMMARY: Solid organ transplantation improves organ function and quality of life; however, bone mineral density can decline following transplantation, particularly during the first three to six months. Immunosuppressive medications, including glucocorticoids, are a major contributing factor. Following transplant, treatment should be tailored to achieve mineral homeostasis, correct nutritional deficiencies, and improve physical conditioning. In summary, early identification and treatment of metabolic bone disease can improve the bone health status of pediatric transplant recipients as they enter adulthood. VIDEO ABSTRACT: http://links.lww.com/MOP/A71.


Assuntos
Doenças Ósseas Metabólicas , Transplante de Órgãos , Humanos , Criança , Densidade Óssea , Qualidade de Vida , Absorciometria de Fóton , Transplante de Órgãos/efeitos adversos , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/etiologia , Glucocorticoides/efeitos adversos
4.
Obesity (Silver Spring) ; 31(11): 2740-2749, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37731271

RESUMO

OBJECTIVE: The objective of this study was to quantify the effects of a 4-week, supervised, high-intensity interval training (HIIT) on intrahepatic triglyceride content (IHTG, percentage), cardiorespiratory fitness (CRF), and cardiometabolic markers in adolescents with obesity. METHODS: A total of 40 adolescents (age 13-18 y, BMI 36.7 ± 5.8 kg/m2 ) at risk for metabolic dysfunction-associated steatotic liver disease (MASLD) based on obesity and elevated Fibroscan measured controlled attenuation parameter (CAP) scores were randomized to HIIT three times a week for 4 weeks (n = 34) or observation (control; n = 6). Liver magnetic resonance imaging proton-density fat-fraction (MRI-PDFF), CAP, oral glucose tolerance test, serum alanine aminotransferase, dual-energy x-ray absorptiometry, and CRF tests were performed before and after intervention. Within- and between-group differences were compared. RESULTS: A total of 13 (38%) and 4 (66%) children had MASLD by MRI-PDFF (IHTG ≥ 5%) in the HIIT and control groups, respectively. The implemented HIIT protocol had no impact on CRF or IHTG (baseline 5.26%, Δ = -0.31 percentage points, 95% CI: -0.77 to 0.15; p = 0.179), but it decreased the 2-h glucose concentration (baseline 116 mg/dL, Δ = -11 mg/dL; 95% CI: -17.6 to -5.5; p < 0.001). When limiting the analysis to participants with MASLD (n = 17), HIIT decreased IHTG (baseline 8.81%, Δ = -1.05 percentage points, 95% CI: -2.08 to -0.01; p = 0.048). Between-group comparisons were not different. CONCLUSIONS: The implemented exercise protocol did not reduce IHTG, but it led to modest improvement in markers of cardiometabolic health.


Assuntos
Doenças Cardiovasculares , Doenças Metabólicas , Obesidade Infantil , Adolescente , Humanos , Exercício Físico , Fígado/diagnóstico por imagem , Sobrepeso , Obesidade Infantil/diagnóstico por imagem , Obesidade Infantil/terapia
5.
Antioxidants (Basel) ; 12(7)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37508015

RESUMO

Aging is associated with a decline in mitochondrial function which may contribute to age-related diseases such as neurodegeneration, cancer, and cardiovascular diseases. Recently, mitochondrial Complex II has emerged as an important player in the aging process. Mitochondrial Complex II converts succinate to fumarate and plays an essential role in both the tricarboxylic acid (TCA) cycle and the electron transport chain (ETC). The dysfunction of Complex II not only limits mitochondrial energy production; it may also promote oxidative stress, contributing, over time, to cellular damage, aging, and disease. Intriguingly, succinate, the substrate for Complex II which accumulates during mitochondrial dysfunction, has been shown to have widespread effects as a signaling molecule. Here, we review recent advances related to understanding the function of Complex II, succinate signaling, and their combined roles in aging and aging-related diseases.

6.
Cell Rep ; 42(8): 112830, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37481724

RESUMO

MYC proto-oncogene dysregulation alters metabolism, translation, and other functions in ways that support tumor induction and maintenance. Although Myc+/- mice are healthier and longer-lived than control mice, the long-term ramifications of more complete Myc loss remain unknown. We now describe the chronic consequences of body-wide Myc inactivation initiated postnatally. "MycKO" mice acquire numerous features of premature aging, including altered body composition and habitus, metabolic dysfunction, hepatic steatosis, and dysregulation of gene sets involved in functions that normally deteriorate with aging. Yet, MycKO mice have extended lifespans that correlate with a 3- to 4-fold lower lifetime cancer incidence. Aging tissues from normal mice and humans also downregulate Myc and gradually alter many of the same Myc target gene sets seen in MycKO mice. Normal aging and its associated cancer predisposition are thus highly linked via Myc.


Assuntos
Senilidade Prematura , Neoplasias , Humanos , Camundongos , Animais , Senilidade Prematura/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Incidência , Neoplasias/patologia , Envelhecimento
7.
Front Endocrinol (Lausanne) ; 13: 937093, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992154

RESUMO

Despite the wealth of information on biomarkers of diabetes complications in adults with type 1 diabetes, data in the pediatric population is limited. Diabetic nephropathy (DN), the leading cause of mortality in type 1 diabetes T1D), could be potentially missed in youth, as albuminuria, the current "gold" standard, may be transient and may not reflect permanent renal impairment. Soluble alpha KL has emerged as a potential marker of early diabetic nephropathy. Seventy-nine pediatric patients with type 1 diabetes meeting ISPAD criteria for nephropathy screening were consecutively recruited (90% Caucasian, 51% male, mean age 16.1 ± 3.1 years, duration of T1D 7.2 ± 3.9 years, 2-year average HbA1c 8.0 ± 1.3%, and serum and urine samples were collected for analysis. Serum Klotho (KL) and circulating miRNA levels of select miRNA involved in the pathogenesis of DN were estimated. KL had a strong inverse correlation with diabetes duration and HbA1c, two important risk factors in the development of diabetes complications. Serum miR-192 were negatively associated with KL among children with prolonged duration of diabetes (≥12 years) after adjustment for age and sex. In cell culture, overexpression of miR-192 significantly downregulated KL mRNA and protein levels, and reduced KL levels in the media. miR-192 mimic reduced luciferase activity in a reporter containing the KL 3' UTR (60% compared to controls, p<0.01), and the inhibitor rescued it. Deletion of a potential binding site for miR-192 in the KL 3'UTR completely abolished the effect of miR-192 in the reporter assay, suggesting that KL is a direct target gene of miR-192. Overexpression of miR-192 significantly increased oxidative stress (MDA) and expression of inflammatory and senescence markers IL-6 and p16. Inhibition of miR-192 significantly reduced levels of MDA, IL-6 and p16. In summary, we demonstrate an increase in miR-192 and a decrease in KL levels in children with prolonged duration of T1D. We demonstrate a novel role for miR-192 in directly regulating KL levels, and through that, senescence and oxidative stress, key pathological processes in the development of DN. miR-192 and/or KL levels are altered with severity and duration of diabetes and could serve as early biomarkers for DN.


Assuntos
Diabetes Mellitus Tipo 1 , Nefropatias Diabéticas , MicroRNAs , Adolescente , Adulto , Biomarcadores/urina , Criança , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Feminino , Hemoglobinas Glicadas , Humanos , Interleucina-6 , Proteínas Klotho , Masculino , Adulto Jovem
8.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743153

RESUMO

Acute myocardial infarction (MI) is one of the leading causes of death worldwide. Early identification of ischemia and establishing reperfusion remain cornerstones in the treatment of MI, as mortality and morbidity can be significantly reduced by establishing reperfusion to the affected areas. The aim of the current study was to investigate the metabolomic changes in the serum in a swine model of MI induced by ischemia and reperfusion (I/R) injury, and to identify circulating metabolomic biomarkers for myocardial injury at different phases. Female Yucatan minipigs were subjected to 60 min of ischemia followed by reperfusion, and serum samples were collected at baseline, 60 min of ischemia, 4 h of reperfusion, and 24 h of reperfusion. Circulating metabolites were analyzed using an untargeted metabolomic approach. A bioinformatic approach revealed that serum metabolites show distinct profiles during ischemia and during early and late reperfusion. Some notable changes during ischemia include accumulation of metabolites that indicate impaired mitochondrial function and N-terminally modified amino acids. Changes in branched-chain amino-acid metabolites were noted during early reperfusion, while bile acid pathway derivatives and intermediates predominated in the late reperfusion phases. This indicates a potential for such an approach toward identification of the distinct phases of ischemia and reperfusion in clinical situations.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Animais , Doença da Artéria Coronariana/complicações , Feminino , Isquemia/complicações , Metabolômica , Isquemia Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/metabolismo , Reperfusão/efeitos adversos , Suínos , Porco Miniatura
9.
J Clin Invest ; 132(14)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35700043

RESUMO

Hepatic inflammation is culpable for the evolution of asymptomatic steatosis to nonalcoholic steatohepatitis (NASH). Hepatic inflammation results from abnormal macrophage activation. We found that FoxO1 links overnutrition to hepatic inflammation by regulating macrophage polarization and activation. FoxO1 was upregulated in hepatic macrophages, correlating with hepatic inflammation, steatosis, and fibrosis in mice and patients with NASH. Myeloid cell conditional FoxO1 knockout skewed macrophage polarization from proinflammatory M1 to the antiinflammatory M2 phenotype, accompanied by a reduction in macrophage infiltration in liver. These effects mitigated overnutrition-induced hepatic inflammation and insulin resistance, contributing to improved hepatic metabolism and increased energy expenditure in myeloid cell FoxO1-knockout mice on a high-fat diet. When fed a NASH-inducing diet, myeloid cell FoxO1-knockout mice were protected from developing NASH, culminating in a reduction in hepatic inflammation, steatosis, and fibrosis. Mechanistically, FoxO1 counteracts Stat6 to skew macrophage polarization from M2 toward the M1 signature to perpetuate hepatic inflammation in NASH. FoxO1 appears to be a pivotal mediator of macrophage activation in response to overnutrition and a therapeutic target for ameliorating hepatic inflammation to stem the disease progression from benign steatosis to NASH.


Assuntos
Proteína Forkhead Box O1 , Hepatopatia Gordurosa não Alcoólica , Hipernutrição , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fibrose , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hipernutrição/patologia
10.
Biochim Biophys Acta Gen Subj ; 1866(1): 130010, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525397

RESUMO

BACKGROUND: Humanin is an endogenous mitochondria-derived peptide that plays critical roles in oxidative stress, inflammation and CAD. In this study, we measured the levels of circulating humanin, markers of oxidative stress and inflammation in patients with unstable angina and MI and studied the relationship between these parameters and major adverse cardiac events (MACE). METHODS: A total of 327 subjects were recruited from the inpatient department at First Hospital of Jilin University and divided into 3 groups [control, angina and myocardial infarction (MI)] based on the clinical data and the results of the angiography. Serum humanin and thiobarbituric acid reactive substances (TBARS) were measured at the time of initial admission. The hospitalization data and MACE of all patients were collected. RESULTS: Circulating humanin levels were lower in the angina group compared to controls [124.22 ±â€¯63.02 vs. 157.77 ±â€¯99.93 pg/ml, p < 0.05] and even lower in MI patients [67.17 ±â€¯24.35 pg/ml, p < 0.05 vs controls] and oxidative stress marker were higher in MI patients compared to the control and angina groups [12.94 ±â€¯4.55 vs. 8.26 ±â€¯1.66 vs. 9.06 ±â€¯2.47 umol/ml, p < 0.05]. Lower circulating humanin levels was an independent risk factor of MI patients. Circulating humanin levels could be used to predict MACE in angina group. CONCLUSIONS: Lower circulating humanin levels was an independent risk factor for CAD, and a potential prognostic marker for mild CAD. GENERAL SIGNIFICANCE: Humanin may become a new index for the diagnosis and treatment of CAD.


Assuntos
Doença da Artéria Coronariana/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/análise , Adulto , Angina Pectoris/metabolismo , Angina Pectoris/fisiopatologia , Biomarcadores/sangue , Doença da Artéria Coronariana/sangue , Feminino , Coração , Humanos , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/sangue , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias , Infarto do Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Prognóstico , Fatores de Risco
11.
Biochim Biophys Acta Gen Subj ; 1866(2): 130066, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34896254

RESUMO

Mitochondria-derived peptides (MDPs) are bioactive peptides encoded by and secreted from the mitochondria. To date, a few MDPs including humanin, MOTS-c and SHLP1-6, and their diverse biological functions have been identified. The first and most studied MDP is humanin, a 24-amino-acid poly peptide. It was first identified in 2001 in the surviving neurons of patient with Alzheimer's disease, and since then has been well characterized for its neuro-protective effect through inhibition of apoptosis. Over the past two decades, humanin has been reported to play critical roles in aging as well as multiple diseases including metabolic disorders, cardiovascular diseases, and autoimmune disease. Humanin has been shown to modulate multiple biological processes including autophagy, ER stress, cellular metabolism, oxidative stress, and inflammation. A role for humanin has been shown in a wide range of cardiovascular diseases, such as coronary heart disease, atherosclerosis, and myocardial fibrosis. In this minireview, we will summarize the literature demonstrating a role for humanin in cardio-protection following myocardial ischemia-reperfusion induced injury and the potential mechanisms that mediate it.


Assuntos
Traumatismo por Reperfusão Miocárdica
12.
Sci Diabetes Self Manag Care ; 47(6): 447-456, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34935539

RESUMO

PURPOSE: The purpose of this study is to survey parents of youth with type 1 diabetes during the COVID-19 pandemic with school closures to better understand the implications of the school day on health care behaviors. METHODS: A cross-sectional, online survey was distributed to parents of youth with type 1 diabetes ≤19 years of age in a large, academic diabetes center. Questions encompassed perceived changes in management behaviors and plans for return to school. Subgroup analysis compared parent responses by child's age, reported stressors, and socioeconomic markers. RESULTS: Parents reported a worsening in their child's diabetes health behaviors during school closures compared to what they perceived during a regular school day before the pandemic. More than half of parents reported feeling that their child was unable to maintain a normal routine, with particular implications for snacking between meals, daily physical activity, and sleep habits. Families with adolescents or those experiencing multiple pandemic-related stressors reported greater challenges. In open-ended responses, families highlighted difficulty in balancing school, work, and diabetes care and expressed concerns about the mental health repercussions of school closures for their children. Nearly half of parents reported being at least moderately worried about return to school, whereas only a minority reported seeking guidance from their diabetes provider. CONCLUSIONS: Parent-reported disruptions of school-day routines frequently had adverse consequences for diabetes management in this population. These findings highlight the importance of a school-day routine for children with type 1 diabetes; during closures, families may benefit from mitigating strategies to maintain effective habits.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Adolescente , Criança , Estudos Transversais , Diabetes Mellitus Tipo 1/epidemiologia , Comportamentos Relacionados com a Saúde , Humanos , Pandemias , Pais , SARS-CoV-2 , Instituições Acadêmicas
13.
Artigo em Inglês | MEDLINE | ID: mdl-36994343

RESUMO

Background: In response to the COVID-19 pandemic, many countries relaxed restrictions on telemedicine, allowing for a robust transition to virtual visits for routine care. In response, centers rapidly instituted and scaled telemedicine for pediatric diabetes care. Despite numerous center reports on their experience, little is known about parent perspectives on the widespread increase of telemedicine for pediatric diabetes appointments. Objective: To assess parent satisfaction with virtual care for pediatric diabetes during the COVID-19 pandemic. Methods: We conducted an online, cross-sectional survey of parents of youth with diabetes who receive care at a large, academic diabetes center regarding their perspectives on newly introduced virtual appointments. Parents were surveyed at two time points during the pandemic using a validated scale which was adapted for diabetes. We explored demographic and clinical factors which may influence parental satisfaction. Results: Overall, parents expressed high levels of satisfaction (>90%) with functional aspects of the visit, though only approximately half (56%) felt the visit was as good as an in-person encounter. Nearly three-quarters (74%) would consider using telemedicine again in the future. Prior use of telemedicine significantly influenced parent satisfaction, suggesting that parent preferences may play a role in continued use of telemedicine in the future. There was no difference in responses across the two timepoints, suggesting high satisfaction early in the pandemic which persisted. Conclusions: If permissive policies for telemedicine continue, diabetes centers could adopt hybrid in-person and virtual care models, while considering various stakeholder perspectives (providers and patients) and equity in access to virtual care.

14.
J Sch Nurs ; 37(4): 259-269, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366301

RESUMO

The purpose of this cross-sectional, descriptive, pilot study was to examine the correlations in sleep between caregivers (≥18 years) and young (6-12 years) children with type 1 diabetes. Sleep was measured in both parent and child over 7 days using actigraphy and a sleep diary. Parents completed questionnaires on sleep, stress, depressive symptoms, and demographics. Children completed pediatric anxiety and fatigue questionnaires, and A1C (Hemoglobin A1c) was documented at clinic. Descriptive statistics and Pearson correlations were used to analyze data. Parents (N = 18, mean age: 39.3 ± 5.4 years, 100% Caucasian, 83% mothers) and children (N = 18, mean age: 9.6 ± 2.4 years, diagnosed for mean 3.0 ± 2.4 years, 66% female, mean A1C: 7.5 ± 0.8%) were recruited. Strong to moderate correlations were found for several measures including sleep measures based on actigraphy: mean sleep duration (hours; 7.6 ± 0.7 for parents and 8.8 ± 0.8 for children; r = .638, p = .004), mean sleep efficiency (r = .823, p < .001), and mean daily wake after sleep onset (minutes; r = .530, p = .024).


Assuntos
Cuidadores , Diabetes Mellitus Tipo 1 , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pais , Projetos Piloto , Sono
16.
JACC Basic Transl Sci ; 5(7): 699-714, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32760857

RESUMO

With the complexities that surround myocardial ischemia/reperfusion (MI/R) injury, therapies adjunctive to reperfusion that elicit beneficial pleiotropic effects and do not overlap with standard of care are necessary. This study found that the mitochondrial-derived peptide S14G-humanin (HNG) (2 mg/kg), an analogue of humanin, reduced infarct size in a large animal model of MI/R. However, when ischemic time was increased, the infarct-sparing effects were abolished with the same dose of HNG. Thus, although the 60-min MI/R study showed that HNG cardioprotection translates beyond small animal models, further studies are needed to optimize HNG therapy for longer, more patient-relevant periods of cardiac ischemia.

17.
Biochem Biophys Res Commun ; 527(1): 162-166, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446361

RESUMO

Dicarboxylic fatty acids, taken as a nutritional supplement or produced endogenously via omega oxidation of monocarboxylic fatty acids, may have therapeutic potential for rare inborn errors of metabolism as well as common metabolic diseases such as type 2 diabetes. Breakdown of dicarboxylic acids yields acetyl-CoA and succinyl-CoA as products, the latter of which is anaplerotic for the TCA cycle. However, little is known about the metabolic pathways responsible for degradation of dicarboxylic acids. Here, we demonstrated with whole-cell fatty acid oxidation assays that both mitochondria and peroxisomes contribute to dicarboxylic acid degradation. Several mitochondrial acyl-CoA dehydrogenases were tested for activity against dicarboxylyl-CoAs. Medium-chain acyl-CoA dehydrogenase (MCAD) exhibited activity with both six and 12 carbon dicarboxylyl-CoAs, and the capacity for dehydrogenation of these substrates was significantly reduced in MCAD knockout mouse liver. However, when dicarboxylic acids were fed to normal mice, the expression of MCAD did not change, while expression of peroxisomal fatty acid oxidation enzymes was greatly upregulated. In conclusion, mitochondrial fatty acid oxidation, and in particular MCAD, contributes to dicarboxylic acid degradation, but feeding dicarboxylic acids induces only the peroxisomal pathway.


Assuntos
Acil-CoA Desidrogenases/metabolismo , Ácidos Dicarboxílicos/metabolismo , Ácidos Graxos/metabolismo , Mitocôndrias/enzimologia , Animais , Masculino , Camundongos , Camundongos Knockout
18.
Neoreviews ; 21(1): e14-e29, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894079

RESUMO

Physiologic adaptations in the postnatal period, along with gradual establishment of enteral feeding, help maintain plasma glucose concentrations in the neonatal period. The definition of normal plasma glucose in the neonatal period has been a subject of debate because of a lack of evidence linking a set plasma or blood glucose concentration to clinical symptoms or predictors of short- and long-term outcomes. However, there is consensus that maintaining plasma glucose in the normal range for age is important to prevent immediate and long-term neurodevelopmental consequences of hypoglycemia or hyperglycemia. The specific management strategy for abnormal glucose levels in neonates depends on the underlying etiology, and interventions could include nutritional changes, medications, hormone therapy, or even surgery. Here, we will review the physiological processes that help maintain plasma glucose in newborns and discuss the approach to a newborn with disordered glucose homeostasis, with an emphasis on the endocrine basis of abnormal glucose homeostasis.


Assuntos
Glicemia , Endocrinologia , Homeostase , Hiperglicemia , Hipoglicemia , Doenças do Recém-Nascido , Glicemia/fisiologia , Homeostase/fisiologia , Humanos , Hiperglicemia/sangue , Hiperglicemia/diagnóstico , Hiperglicemia/etiologia , Hiperglicemia/terapia , Hipoglicemia/sangue , Hipoglicemia/diagnóstico , Hipoglicemia/etiologia , Hipoglicemia/terapia , Recém-Nascido , Doenças do Recém-Nascido/sangue , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/etiologia , Doenças do Recém-Nascido/terapia
19.
Diabetologia ; 62(12): 2325-2339, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31511929

RESUMO

AIMS/HYPOTHESIS: Absent in melanoma 2 (AIM2) is a cytosolic sensor for double-stranded DNA and a tumour suppressor. Binding of double-stranded DNA to AIM2 forms the AIM2 inflammasome, leading to activation of caspase-1 and production of IL-1ß and IL-18. Although inflammasome-independent effects of AIM2 have been reported, its role in energy metabolism is unknown. We aimed to evaluate the effect of AIM2 in energy metabolism and glucose homeostasis. METHODS: Male and female whole body Aim2 knockout (Aim2-/-) mice were used in the current study. Body weight, food intake, body composition, energy expenditure, fasting blood glucose levels, GTT and body temperature were measured at indicated time points. RNA sequencing was carried out on gonadal white adipose tissue (gWAT) in 14-month-old female mice. mRNA and protein levels in tissues were analysed by quantitative real-time PCR and immunoblot. Immune cell infiltration in gWAT was examined by flow cytometry. Stromal vascular fractions isolated from gWAT were used to investigate adipocyte differentiation. RESULTS: Male and female Aim2-/- mice were obese compared with wild-type controls from 7 weeks of age until 51 weeks of age, with increased adiposity in both subcutaneous and visceral fat depots. While there were no differences in food intake, Aim2-/- mice demonstrated decreased energy expenditure and impaired brown adipose tissue function compared with wild-type controls. Fasting glucose and insulin levels were elevated, and Aim2-/- mice were glucose intolerant on intraperitoneal GTT. RNA sequencing revealed marked upregulation of the IFN-inducible gene Ifi202b, which encodes protein 202 (p202) and elevated inflammatory signalling in gWAT of Aim2-/- mice. Increased infiltration of total and Ly6Clow monocytes was noted at 8 weeks of age in gWAT, before the onset of obesity and insulin resistance. Ifi202b knockdown blocked adipogenesis in stromal vascular fractions and reduced inflammation in bone marrow-derived macrophages, demonstrating a key role of p202 in mediating the increased adipogenesis and inflammation in Aim2-/- mice. CONCLUSIONS/INTERPRETATION: These results demonstrate a fundamental role for AIM2 in energy metabolism, inflammation and insulin resistance. Our studies establish a novel link between the innate immunity proteins, AIM2 and p202, and metabolism.


Assuntos
Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Proteínas de Ligação a DNA/metabolismo , Inflamação/metabolismo , Resistência à Insulina/genética , Obesidade/metabolismo , Tecido Adiposo Marrom/metabolismo , Adiposidade/genética , Animais , Glicemia/metabolismo , Temperatura Corporal/genética , Proteínas de Ligação a DNA/genética , Ingestão de Alimentos/genética , Metabolismo Energético/genética , Jejum/metabolismo , Feminino , Inflamação/genética , Masculino , Camundongos , Camundongos Knockout , Obesidade/genética
20.
Am J Physiol Renal Physiol ; 317(5): F1318-F1330, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509011

RESUMO

The incidence of diabetes mellitus has significantly increased among women of childbearing age, and it has been shown that prenatal exposure to maternal diabetes increases the risk of associated congenital anomalies of the kidney. Congenital anomalies of the kidney are among the leading causes of chronic kidney disease in children. To better understand the effect of maternal diabetes on kidney development, we analyzed wild-type offspring (DM_Exp) of diabetic Ins2+/C96Y mice (Akita mice). DM_Exp mice at postnatal day 34 have a reduction of ~20% in the total nephron number compared with controls, using the gold standard physical dissector/fractionator method. At the molecular level, the expression of the nephron progenitor markers sine oculis homeobox homolog 2 and Cited1 was increased in DM_Exp kidneys at postnatal day 2. Conversely, the number of early developing nephrons was diminished in DM_Exp kidneys. This was associated with decreased expression of the intracellular domain of Notch1 and the canonical Wnt target lymphoid enhancer binding factor 1. Together, these data suggest that the diabetic intrauterine environment impairs the differentiation of nephron progenitors into nephrons, possibly by perturbing the Notch and Wnt/ß-catenin signaling pathways.


Assuntos
Diabetes Gestacional , Insulina/genética , Néfrons/crescimento & desenvolvimento , Células-Tronco/metabolismo , Animais , Animais Recém-Nascidos , Diferenciação Celular , Feminino , Predisposição Genética para Doença , Genótipo , Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Masculino , Camundongos , Mutação , Gravidez , Fatores de Transcrição/metabolismo
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