Postnatal Loss of the Insulin Receptor in Osteoprogenitor Cells Does Not Impart a Metabolic Phenotype

The relationship between osteoblast-specific insulin signaling, osteocalcin activation and gluco-metabolic homeostasis has proven to be complex and potentially inconsistent across animal-model systems and in humans. Moreover, the impact of postnatally acquired, osteoblast-specific insulin deficiency on the pancreas-to-skeleton-to-pancreas circuit has not been studied. To explore this relationship, we created a model of postnatal elimination of insulin signaling in osteoprogenitors. Osteoprogenitor-selective ablation of the insulin receptor was induced after ~10 weeks of age in IRl°x/lox/Osx-Cre+/− genotypic male and female mice (designated postnatal-OIRKO). At ~21 weeks of age, mice were then phenotypically and metabolically characterized. Postnatal-OIRKO mice demonstrated a significant reduction in circulating concentrations of undercarboxylated osteocalcin (ucOC), in both males and females compared with control littermates. However, no differences were observed between postnatal-OIRKO and control mice in: body composition (lean or fat mass); fasting serum insulin; HbA1c; glucose dynamics during glucose tolerance testing; or in pancreatic islet area or islet morphology, demonstrating that while ucOC is impacted by insulin signaling in osteoprogenitors, there appears to be little to no relationship between osteocalcin, or its derivative (ucOC), and glucose homeostasis in this model

Preserving and Restoring Bone with Continuous Insulin Infusion Therapy in a Mouse Model of Type 1 Diabetes

Those with type 1 diabetes (T1D) are more likely to suffer a fracture than age- and sex-matched individuals without diabetes, despite daily insulin therapy. In rodent studies examining the effect of bone- or glucose-targeting therapies on preventing the T1D-related decrease in bone strength, insulin co-therapy is often not included, despite the known importance of insulin signaling to bone mass accrual. Therefore, working toward a relevant pre-clinical model of diabetic bone disease, we assessed the effect of continuous subcutaneous insulin infusion (CSII) therapy at escalating doses on preserving bone and the effect of delayed CSII on rescuing the T1D-related bone deterioration in an established murine model of T1D. Osmotic minipumps were implanted in male DBA/2 J mice 2 weeks (prevention study) and 6 weeks (rescue study) after the first injection of streptozotocin (STZ) to deliver insulin at 0, 0.0625, 0.125, or 0.25 IU/day (prevention study; n = 4–5 per dose) and 0 or 0.25 IU/day (rescue study; n = 10 per group). CSII lasted 4 weeks in both studies, which also included age-matched, non-diabetic DBA/2 J mice (n = 8–12 per study). As the insulin dose increased, blood glucose decreased, body weight increased, a serum maker of bone resorption decreased, and a serum marker of bone formation increased such that each end-point characteristic was linearly correlated with dose. There were insulin dose-dependent relationships (femur diaphysis) with cross-sectional area of cortical bone and cortical thickness (micro-computed tomography) as well as structural strength (peak force endured by the mid-shaft during three-point bending). Likewise, trabecular bone volume fraction (BV/TV), thickness, and number (distal femur metaphysis) increased as the insulin dose increased. Delayed CSII improved glycated hemoglobin (HbA1c), but blood glucose levels remained relatively high (well above non-diabetic levels). Interestingly, it returned the resorption and formation markers to similar levels as those seen in non-T1D control mice. This apparent return after 4 weeks of CSII translated to a partial rescue of the structural strength of the femur mid-shaft. Delayed CSII also increased Tb.Th to levels seen in non-T1D controls but did not fully restore BV/TV. The use of exogenous insulin should be considered in pre-clinical studies investigating the effect of T1D on bone as insulin therapy maintains bone structure without necessarily lowering glucose below diabetic levels

The Impact of SGLT2 Inhibitors, Compared with Insulin, on Diabetic Bone Disease in a Mouse Model of Type 1 Diabetes

Skeletal co-morbidities in type 1 diabetes include an increased risk for fracture and delayed fracture healing, which are intertwined with disease duration and the presence of other diabetic complications. As such, chronic hyperglycemia is undoubtedly a major contributor to these outcomes, despite standard insulin-replacement therapy. Therefore, using the streptozotocin (STZ)-induced model of hypoinsulinemic hyperglycemia in DBA/2J male mice, we compared the effects of two glucose lowering therapies on the fracture resistance of bone and markers of bone turnover. Twelve week-old diabetic (DM) mice were treated for 9 weeks with: 1) oral canagliflozin (CANA, dose range ~10-16 mg/kg/day), an inhibitor of the renal sodium-dependent glucose co-transporter type 2 (SGLT2); 2) subcutaneous insulin, via minipump (INS, 0.125 units/day); 3) co-therapy (CANA + INS); or 4) no treatment (STZ, without therapy). These groups were also compared to non-diabetic control groups. Untreated diabetic mice experienced increased bone resorption and significant deficits in cortical and trabecular bone that contributed to structural weakness of the femur mid-shaft and the lumbar vertebra, as determined by three-point bending and compression tests, respectively. Treatment with either canagliflozin or insulin alone only partially rectified hyperglycemia and the diabetic bone phenotype. However, when used in combination, normalization of glycemic control was achieved, and a prevention of the DM-related deterioration in bone microarchitecture and bone strength occurred, due to additive effects of canagliflozin and insulin. Nevertheless, CANA-treated mice, whether diabetic or non-diabetic, demonstrated an increase in urinary calcium loss; FGF23 was also increased in CANA-treated DM mice. These findings could herald ongoing bone mineral losses following CANA exposure, suggesting that certain CANA-induced skeletal consequences might detract from therapeutic improvements in glycemic control, as they relate to diabetic bone disease

Multilingual global e-learning pediatric endocrinology and diabetes curriculum for front line health care providers in resource-limited countries: Development study

Background: Electronic learning (e-learning) is a widely accessible, low-cost option for learning remotely in various settings that allows interaction between an instructor and a learner. Objective: We describe the development of a free and globally accessible multilingual e-learning module that provides education material on topics in pediatric endocrinology and diabetes and that is intended for first-line physicians and health workers but also trainees or medical specialists in resource-limited countries. Methods: As complements to concise chapters, interactive vignettes were constructed, exemplifying clinical issues and pitfalls, with specific attention to the 3 levels of medical health care in resource-limited countries. The module is part of a large e-learning portal, ESPE e-learning, which is based on ILIAS (Integriertes Lern-, Informations-und Arbeitskooperations-System), an open-source web-based learning management system. Following a review by global experts, the content was translated by native French, Spanish, Swahili, and Chinese-speaking colleagues into their respective languages using a commercial web-base

Addressing Energy Poverty through Transitioning to a Carbon-Free Environment

The excessive consumption of fossil fuels not only leads to resource depletion, but also involves negative environmental effects on both public health and the climate. However, Greece’s renewable energy (RE) capacity is considerable and could meet a great part of the country’s energy needs while helping to tackle the ecological problem our planet faces. At the same time, the deployment of renewable energy sources (RES) can facilitate the creation of new jobs and enable households to become energy independent, while addressing energy poverty. The present study investigates the views and attitudes of citizens of the Thessaloniki conurbation towards RES. To collect the data, structured questionnaires were used, which were completed through personal interviews. Moreover, random sampling was performed to select the sample, and in total 420 citizens participated in the survey. Results showed that the respondents supported the replacement of lignite plants with renewable energy sources since they perceived that they constitute a necessary solution providing opportunities for economic growth and improvement to their quality of life. Finally, the vast majority expressed increased interest in future investment in photovoltaic systems, which in their opinion could contribute to improving air quality and increasing the energy independence not only of Greece but also of households

Biomechanical Stimulation of Muscle Constructs Influences Phenotype of Bone Constructs by Modulating Myokine Secretion

ABSTRACT Diabetes is a chronic metabolic disorder that can lead to diabetic myopathy and bone diseases. The etiology of musculoskeletal complications in such metabolic disorders and the interplay between the muscular and osseous systems are not well understood. Exercise training promises to prevent diabetic myopathy and bone disease and offer protection. Although the muscle‐bone interaction is largely biomechanical, the muscle secretome has significant implications for bone biology. Uncoupling effects of biophysical and biochemical stimuli on the adaptive response of bone during exercise training may offer therapeutic targets for diabetic bone disease. Here, we have developed an in vitro model to elucidate the effects of mechanical strain on myokine secretion and its impact on bone metabolism decoupled from physical stimuli. We developed bone constructs using cross‐linked gelatin, which facilitated osteogenic differentiation of osteoprogenitor cells. Then muscle constructs were made from fibrin, which enabled myoblast differentiation and myotube formation. We investigated the myokine expression by muscle constructs under strain regimens replicating endurance (END) and high‐intensity interval training (HIIT) in hyperglycemic conditions. In monocultures, both regimens induced higher expression of Il15 and Igf1, whereas END supported more myoblast differentiation and myotube maturation than HIIT. When co‐cultured with bone constructs, HIIT regimen increased Glut4 expression in muscle constructs more than END, supporting higher glucose uptake. Likewise, the muscle constructs under the HIIT regimen promoted a healthier and more matured bone phenotype than END. Under static conditions, myostatin (Mstn) expression was significantly downregulated in muscle constructs co‐cultured with bone constructs compared with monocultures. Together, our in vitro co‐culture system allowed orthogonal manipulation of mechanical strain on muscle constructs while facilitating bone‐muscle biochemical cross‐talk. Such systems can provide an individualized microenvironment that allows decoupled biomechanical manipulation, help identify molecular targets, and develop engineered therapies for metabolic bone disease. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research

Preserving and restoring bone with continuous insulin infusion therapy in a mouse model of type 1 diabetes

Those with type 1 diabetes (T1D) are more likely to suffer a fracture than age- and sex-matched individuals without diabetes, despite daily insulin therapy. In rodent studies examining the effect of bone- or glucose-targeting therapies on preventing the T1D-related decrease in bone strength, insulin co-therapy is often not included, despite the known importance of insulin signaling to bone mass accrual. Therefore, working toward a relevant pre-clinical model of diabetic bone disease, we assessed the effect of continuous subcutaneous insulin infusion (CSII) therapy at escalating doses on preserving bone and the effect of delayed CSII on rescuing the T1D-related bone deterioration in an established murine model of T1D. Osmotic minipumps were implanted in male DBA/2 J mice 2 weeks (prevention study) and 6 weeks (rescue study) after the first injection of streptozotocin (STZ) to deliver insulin at 0, 0.0625, 0.125, or 0.25 IU/day (prevention study; n = 4–5 per dose) and 0 or 0.25 IU/day (rescue study; n = 10 per group). CSII lasted 4 weeks in both studies, which also included age-matched, non-diabetic DBA/2 J mice (n = 8–12 per study). As the insulin dose increased, blood glucose decreased, body weight increased, a serum maker of bone resorption decreased, and a serum marker of bone formation increased such that each end-point characteristic was linearly correlated with dose. There were insulin dose-dependent relationships (femur diaphysis) with cross-sectional area of cortical bone and cortical thickness (micro-computed tomography) as well as structural strength (peak force endured by the mid-shaft during three-point bending). Likewise, trabecular bone volume fraction (BV/TV), thickness, and number (distal femur metaphysis) increased as the insulin dose increased. Delayed CSII improved glycated hemoglobin (HbA1c), but blood glucose levels remained relatively high (well above non-diabetic levels). Interestingly, it returned the resorption and formation markers to similar levels as those seen in non-T1D control mice. This apparent return after 4 weeks of CSII translated to a partial rescue of the structural strength of the femur mid-shaft. Delayed CSII also increased Tb.Th to levels seen in non-T1D controls but did not fully restore BV/TV. The use of exogenous insulin should be considered in pre-clinical studies investigating the effect of T1D on bone as insulin therapy maintains bone structure without necessarily lowering glucose below diabetic levels

Ten-years experience of a global and freely accessible e-Learning website for paediatric endocrinology and diabetes

The European Society for Paediatric Endocrinology (ESPE) interactive website https://www.espe-elearning.org was first published online in 2012. We describe the various applications of the content of the e-Learning website that has been greatly expanded over the last 10 years. A large module on paediatric diabetes was added with the support of the International Society for Paediatric and Adolescent Diabetes (ISPAD). A separate multilingual module was created that focuses on front-line health care providers in limited resource settings. This module has been well received particularly in targeted parts of the world. E-learning may also be an opportunity to expand or tailor educational activities for learners according to their differing learning needs. The e-Learning website provides guidelines for those interested in general pediatrics, neonatology, clinical genetics and pediatric gynecology. We also describe various new applications such as masterclasses in the format of interactive video lectures and joined and complementary e-Learning/e-Consultation webinars. Finally, international certification was recently realized as e-Learning courses were recognized by the European Accreditation Council for Continuing Medical Education (EACCME). As a result of the social distancing measures introduced to control the COVID-19 pandemic digital education, whether individual or in a virtual classroom setting, has become even more important since e-Learning can connect and engage individuals across geographic boundaries as well as those who live in remote areas. The future of education delivery may include hybrid learning strategies, which include in-person and e-Learning platforms. Combined e-Learning and e-Consultation webinars illustrate how international academic institutions, learned medical specialty societies and networks are uniquely placed to deliver balanced, disease oriented and patient-centred e-Learning education and at the same time as providing expert consultation

10 years' experience of a global and freely accessible e-Learning website for paediatric endocrinology and diabetes

The European Society for Paediatric Endocrinology (ESPE) interactive website https://www.espe-elearning.org was first published online in 2012. We describe the various applications of the content of the e-Learning website that has been greatly expanded over the last 10 years. A large module on paediatric diabetes was added with the support of the International Society for Paediatric and Adolescent Diabetes (ISPAD). A separate multilingual module was created that focuses on front-line health care providers in limited resource settings. This module has been well received particularly in targeted parts of the world. E-learning may also be an opportunity to expand or tailor educational activities for learners according to their differing learning needs. The e-Learning website provides guidelines for those interested in general pediatrics, neonatology, clinical genetics and pediatric gynecology. We also describe various new applications such as masterclasses in the format of interactive video lectures and joined and complementary e-Learning/e-Consultation webinars. Finally, international certification was recently realized as e-Learning courses were recognized by the European Accreditation Council for Continuing Medical Education (EACCME). As a result of the social distancing measures introduced to control the COVID-19 pandemic digital education, whether individual or in a virtual classroom setting, has become even more important since e-Learning can connect and engage individuals across geographic boundaries as well as those who live in remote areas. The future of education delivery may include hybrid learning strategies, which include in-person and e-Learning platforms . Combined e-Learning and e-Consultation webinars illustrate how international academic institutions, learned medical specialty societies and networks are uniquely placed to deliver balanced, disease oriented and patient-centred e-Learning education and at the same time as providing expert consultation . Moreover, they are well equipped to maintain professional standards and to offer appropriate accreditation

Bringing the Pediatric Endocrine Spanish Speaking Community Together: First Virtual Pediatric Endocrine Meeting in Low- and Middle-Income Countries in Central and South America

BackgroundPediatric endocrinology is a specialty that is struggling worldwide to maintain adequately trained professionals. Pediatric endocrine care in Central America and Caribbean countries is often performed by pediatricians or adult endocrinologists due to the limited number of pediatric endocrinologists. These health care providers are seldom members of endocrine societies and frequently lack formal training in the field. ObjectiveIn this study, we describe the scope of a virtual conference in pediatric endocrinology and diabetes targeted to low- and middle-income countries to provide equal opportunities for access to medical education for health care professionals. MethodsThe virtual conference was sponsored by the Pediatric Endocrine Society (North America), Asociación Costarricense de Endocrinología (previously, Asociación Nacional Pro Estudio de la Diabetes, Endocrinología y Metabolismo), and Asociacion Centroamericana y del Caribe de Endocrinologia Pediátrica. The conference was free to participants and comprised 23 sessions that were either synchronous with ability for real-time interactive sessions or asynchronous sessions, where content was available online to access at their convenience. Topics included idiopathic short stature, polycystic ovarian syndrome, diabetes mellitus, telemedicine, Turner syndrome, congenital adrenal hyperplasia, obesity, central precocious puberty, and subclinical hypothyroidism. The participants were asked to evaluate the conference after its completion with a questionnaire. ResultsA total of 8 speakers from Spain, Canada, Costa Rica, and the United States delivered the virtual event to 668 health care professionals from Guatemala, Venezuela, Dominican Republic, Costa Rica, Ecuador, Peru, Uruguay, Mexico, Honduras, Argentina, the United States, Bolivia, Chile, Panama, El Salvador, Nicaragua, Paraguay, Belize, Spain, and Colombia. Name, profession, and country were fully disclosed by 410 (61.4%) of the 668 health care professionals. The profession or level of training of participants were as follows: pediatric endocrinologists (n=129, 19.3%), pediatricians (n=116, 17.4%), general practitioners (n=77, 11.5%), adult endocrinologists (n=34, 5.1%), medical students (n=23, 3.4%), residents in various specialties (n=14, 2.1%), and others (n=17, 2.6%). A total of 23 sessions were offered, most of which were bilingual (Spanish and English). Feedback from the evaluation questionnaire indicated that the content of the conference was very relevant to the participants’ professional practice. Additionally, the participants reported that they were very satisfied with the organization, the web-based platform, and the sessions of the conference. ConclusionsLack of accessibility to the latest and cutting-edge medical education in pediatric endocrinology and diabetes for medical professionals from low- and middle-income countries can be overcome with a virtual conference. Online availability, low cost, and easy-to-use technology were well received from the participants, who were overall very satisfied by the quality and the relevance of the sessions to their professional practice