Liver-specific deletion of the growth hormone receptor reveals essential role of growth hormone signaling in hepatic lipid metabolism

Growth hormone (GH) plays a pivotal role in growth and metabolism, with growth promotion mostly attributed to generation of insulin-like growth factor I (IGF-I) in liver or at local sites of GH action, whereas the metabolic effects of GH are considered to be intrinsic to GH itself. To distinguish the effects of GH from those of IGF-I, we developed a Cre-lox-mediated model of tissue-specific deletion of the growth hormone receptor (GHR). Near total deletion of the GHR in liver (GHRLD) had no effect on total body or bone linear growth despite a >90% suppression of circulating IGF-I; however, total bone density was significantly reduced. Circulating GH was increased 4-fold, and GHRLD displayed insulin resistance, glucose intolerance, and increased circulating free fatty acids. Livers displayed marked steatosis, the result of increased triglyceride synthesis and decreased efflux; reconstitution of hepatic GHR signaling via adenoviral expression of GHR restored triglyceride output to normal, whereas IGF-I infusion did not correct steatosis despite restoration of circulating GH to normal. Thus, with near total absence of circulating IGF-I, GH action at the growth plate, directly and via locally generated IGF-I, can regulate bone growth, but at the expense of diabetogenic, lipolytic, and hepatosteatotic consequences. Our results indicate that IGF-I is essential for bone mineral density, whereas hepatic GH signaling is essential to regulate intrahepatic lipid metabolism. We propose that circulating IGF-I serves to amplify the growth-promoting effects of GH, while simultaneously dampening the catabolic effects of GH.

Molecular imaging of the skeleton: quantitative real-time bioluminescence monitoring gene expression in bone repair and development

Monitoring gene expression in vivo, noninvasively, is a critical issue in effective gene therapy systems. To date, there are no adequate molecular imaging techniques, which quantitatively monitor gene expression in vivo in skeletal development and repair. The aim of this study was to monitor gene expression in skeletal development and repair, using a real-time molecular imaging system, which quantitatively and noninvasively detects bioluminescence in vivo. Our experimental model consisted of transgenic mice harboring the luciferase marker gene under the regulation of the human osteocalcin (hOC) promoter. A new light detection cooled charge coupled device (CCCD) camera was applied to monitor luciferase expression. In vitro, mesenchymal stem cells (MSCs) isolated from bone marrow of transgenic mice exhibited hOC promoter regulation, detected by luciferase expression that correlated with their osteogenic differentiation. During development from 1 week to 1.5 years, transgenic mice exhibited transgene expression in a wide spectrum of skeletal organs, including calvaria, vertebra, tail, and limbs, reaching a peak at 1 week in most of the skeletal organs. In two skeletal repair models, bone fracture and marrow ablation, the noninvasive CCCD system revealed a peak of luciferase expression at 6 days postsurgery. All quantitative, noninvasive, real-time CCCD measurements correlated with a luciferase biochemical assay and luciferase immunohistochemistry, which demonstrated luciferase expression in hypertrophic chondrocytes and trabecular osteoblasts. Our studies show for the first time (1) the CCCD detection system is a reliable quantitative gene detection tool for the skeleton in vivo, (2) expression of luciferase regulated by the hOC promoter is significantly decreased with age in most skeletal sites, and (3) the dynamics of hOC regulation during mice skeletal development and repair in real time, quantitatively and noninvasively.

Plastic debris as nesting material in a Kittiwake-(Rissa tridactyla)-colony at the Jammerbugt, Northwest Denmark

This paper continues the investigations of Clemens and Hartwig from 1992 on the proportion of garbage used as nesting material in the Kittiwake colony at Bulbjerg in the Jammerbugt in Northwest Denmark. Whereas in the year 1992 plastic garbage items were included in 39.3% of 466 Kittiwake nests in the Bulbjerg colony, in 2005 57.2% of 311 nests contained plastic debris. Although it has been forbidden to dispose of plastic garbage into the marine environment since the implementation of the MARPOL 73/78-Agreement/Annex V (Regulation for the Prevention of Pollution by Ship Waste) of 1989 and especially since the declaration of the North Sea as a MARPOL-Special Area for garbage in 1991, the pollution of the oceans and the North Sea is still an ubiquitous problem, particularly with regard to plastic waste. Plastic waste is presumably not used preferentially for nest-building, but in the context of available nesting material in the waters surrounding the breeding colony. Therefore the share of garbage parts in nests of certain species of birds is an indicator of the amount of waste in the natural environment in the vicinity of their breeding site.

Co-ordination of TGF-beta and FGF signaling pathways in bone organ cultures

Transforming growth factor-beta (TGF-beta) is known to regulate chondrocyte proliferation and hypertrophic differentiation in embryonic bone cultures by a perichondrium dependent mechanism. To begin to determine which factors in the perichondrium mediate the effects of TGF-beta, we studied the effect of Insulin-like Growth Factor-1 (IGF-I) and Fibroblast Growth Factors-2 and -18 (FGF2, FGF18) on metatarsal organ cultures. An increase in chondrocyte proliferation and hypertrophic differentiation was observed after treatment with IGF-I. A similar effect was seen after the perichondrium was stripped from the metatarsals suggesting IGF-I acts directly on the chondrocytes. Treatment with FGF-2 or FGF-18 resulted in a decrease in bone elongation as well as hypertrophic differentiation. Treatment also resulted in a decrease in BrdU incorporation into chondrocytes and an increase in BrdU incorporation in perichondrial cells, similar to what is seen after treatment with TGF-beta1. A similar effect was seen with FGF2 after the perichondrium was stripped suggesting that, unlike TGF-beta, FGF2 acts directly on chondrocytes to regulate proliferation and hypertrophic differentiation. To test the hypothesis that TGF-beta regulates IGF or FGF signaling, activation of the receptors was characterized after treatment with TGF-beta. Activation was measured as the level of tyrosine phosphorylation on the receptor. Treatment with TGF-beta for 24h did not alter the level of IGFR-I tyrosine phosphorylation. In contrast, treatment with TGF-beta resulted in and increase in tyrosine phosphorylation on FGFR3 without alterations in total FGFR3 levels. TGF-beta also stimulated expression of FGF18 mRNA in the cultures and the effects of TGF-beta on metatarsal development were blocked or partially blocked by pretreatment with FGF signaling inhibitors. The results suggest a model in which FGF through FGFR3 mediates some of the effects of TGF-beta on embryonic bone formation.

Ultraviolet A radiation and COVID-19 deaths in the USA with replication studies in England and Italy

Background

Understanding factors impacting deaths from COVID‐19 is of the highest priority. Seasonal variation in environmental meteorological conditions affects the incidence of many infectious diseases and may also affect COVID‐19. Ultraviolet (UV) A (UVA) radiation induces release of cutaneous photolabile nitric oxide (NO) impacting the cardiovascular system and metabolic syndrome, both COVID‐19 risk factors. NO also inhibits the replication of SARS‐CoV2.

Objectives

To investigate the relationship between ambient UVA radiation and COVID‐19 deaths.

Methods

COVID‐19 deaths at the county level, across the USA, were modelled in a zero‐inflated negative‐binomial model with a random effect for states adjusting for confounding by demographic, socioeconomic and long‐term environmental variables. Only those areas where UVB was too low to induce significant cutaneous vitamin D3 synthesis were modelled. We used satellite‐derived estimates of UVA, UVB and temperature and relative humidity. Replication models were undertaken using comparable data for England and Italy.

Results

The mortality rate ratio (MRR) in the USA falls by 29% [95% confidence interval (CI) 40% to 15%) per 100 kJ m^–2 increase in mean daily UVA. We replicated this in independent studies in Italy and England and estimate a pooled decline in MRR of 32% (95% CI 48% to 12%) per 100 kJ m^–2 across the three studies.

Conclusions

Our analysis suggests that higher ambient UVA exposure is associated with lower COVID‐19‐specific mortality. Further research on the mechanism may indicate novel treatments. Optimized UVA exposure may have population health benefits.

Statistical analyses of the results of 25 years of beach litter surveys on the south-eastern North Sea coast

In the North Sea, the amount of litter present in the marine environment represents a severe environmental problem. In order to assess the magnitude of the problem and measure changes in abundance, the results of two beach litter monitoring programmes were compared and analysed for long-term trends applying multivariate techniques. Total beach litter pollution was persistently high. Spatial differences in litter abundance made it difficult to identify long-term trends: Partly more than 8000 litter items year(-1) were recorded on a 100 m long survey site on the island of Scharhörn, while the survey site on the beach on the island of Amrum revealed abundances lower by two orders of magnitude. Beach litter was dominated by plastic with mean proportions of 52%-91% of total beach litter. Non-parametric time series analyses detected many significant trends, which, however, did not show any systematic spatial patterns. Cluster analyses partly led to groupings of beaches according to their expositions to sources of litter, wind and currents. Surveys in short intervals of one to two weeks were found to give higher annual sums of beach litter than the quarterly surveys of the OSPAR method. Surveys at regular intervals of four weeks to five months would make monitoring results more reliable.

The European Semester 2015-2018: themes and progress of country specific recommendations on health

Background

The European Semester (ES) is a policy coordination and scrutiny framework at EU-level for surveillance of fiscal and macro-economic policies in Member States. Health systems have not evaded that scrutiny. The analysis focusses on how health systems reforms are being endorsed in Country Specific Recommendations (CSRs) and how the ES process links to planning and implementation of national health system reforms over the period 2015-2018.

Methods

A descriptive content analysis of CSRs with a search for the keywords and phrases ‘health’, OR ‘healthcare’, OR ‘long-term care’ was performed for the years 2015-2018. Furthermore, CSRs addressing health systems were classified according to whether they were targeting access, quality or sustainability; and categorized regarding organisation and governance, financing, physical and human resources, and provision of services. Finally, implementation progress on the health CSRs was rated according to EC’s own evaluation scheme derived from the preceding year’s country report.

Results

CSRs with health system recommendations have featured continuously in the ES process each year and have stabilised in number. The themes of health CSRs are still dominated by financial sustainability, cost-effectiveness and of financing, although other health system goals and domains, particularly access, are increasingly addressed. There is a high degree of consistency on the content of health CSRs over the years for each country addressed. Progress with implementation of health CSRs is disappointing so far, based on the EC evaluations. No clear link between discontinuation of health CSRs and evidence of progress in implementing the CSR can be discerned.

Conclusions

The results uncovered some of the links between national and European institutions leveraging the ES to push health system reforms. However, a more balanced and long-term view is needed for the ES to contribute solidly to complementing national efforts in a complex reform context.

Key messages

Health CSRs are still dominated by financial sustainability considerations while other health system goals and domains are increasingly addressed. Progress with implementation of health CSRs is disappointing so far, although a longer-term perspective is needed to pay tribute to the complex reform environment of health system reforms.

Advancing the social return on investment framework to capture the social value of public health interventions: semistructured interviews and a review of scoping reviews

OBJECTIVES

Investment in public health has far-reaching impacts, not only on physical health but also on communities, economies and the environment. There is increasing demand to account for the wider impact of public health and the social value that can be created, which can be captured through the use of the social return on investment (SROI) framework. This study aims to explore the application of SROI and identify areas of advancement for its use in public health.

STUDY DESIGN AND METHODS

Publically available SROI studies of public health interventions previously identified through published systematic scoping reviews were examined through a methodological lens. This was complemented by semistructured interviews with key public health academic experts with experience in the field of SROI. The results were thematically analysed and triangulated.

RESULTS

In total, 53 studies and nine interviews were included in the analysis. All interviewees agreed that SROI is a suitable framework to demonstrate the social value of public health interventions. Developmental aspects were also identified through the analysis. This included a more systematic use of SROI principles and methodological developments. Lastly, it was identified that further advancements were needed to promote awareness of SROI and how it can be used to generate investment.

CONCLUSION

By identifying key areas for advancement, the results from this study can be used to further refine the SROI framework for use within the speciality to promote investment in services and interventions that demonstrate maximum value to people, communities, economies and the environment.

20-Year trends of hospitalisation among people with dementia: a region-wide retrospective cohort study from Lombardy, Italy

OBJECTIVES

The aim of this study was to investigate the trends of hospitalisations among people with dementia, linking region-wide hospital and demographic health records.

STUDY DESIGN

A retrospective cohort study was conducted using hospitalisation health records from the Lombardy region in Italy.

METHODS

The study included people aged ≥65 years with a diagnosis of dementia who were hospitalised between 2002 and 2020 in Lombardy, which is the most populated region in Italy with 10 million inhabitants. Using data on resident population, this study computed rates of hospitalisation by calendar year, age, sex and cause of hospitalisation.

RESULTS

In total, 340,144 hospitalised patients with dementia were included in the study. The rate of hospitalisation was 100.6 per 10,000 in 2002 and progressively decreased to 65.1 per 10,000 in 2020. The average age at hospitalisation in 2002 was 78.9 years for men and 81.8 years for women, which increased to 82.0 years and 84.2 years, respectively, in 2020. Respiratory diseases caused 10.4% of all hospitalisations in 2002 and grew steadily to 26.8% in 2020, becoming the leading cause of hospital admissions since 2017.

CONCLUSIONS

Hospitalisation patterns for people with dementia have changed over the last 20 years, reflecting evolving epidemiological trends and the impact of healthcare policies. Region-wide administrative health record data analysis should be further utilised to explore the health needs of people with dementia and inform the planning, implementation and monitoring of effective prevention strategies in this population group.

Leveraging Citizen Science to Improve Urban Public Health

Background

Mobile health approaches in community based participatory projects keep the promise to encourage sustainable behavior in citizens by engaging communities in data collection and connecting their individual level behavior to larger level community health. This review evaluates the effectiveness of the implementation of citizen science for health promotion of non-communicable diseases in urban community-based participatory research projects.

Methods

A scoping review was conducted using PRISMA-ScR. Pubmed and Web of Science were searched for citizen science studies. We included research 1.) conducted in an urban setting, 2.) related to environmental sustainability, 3.) focused on non-communicable diseases, and 4.) applied citizen science methodology.

Results

32 community-based participatory research projects were identified using the following data collection technologies: mobile applications (n = 7), photovoice (n = 6), Stanford Healthy Neighborhood Discovery Tool (n = 6), monitoring (n = 6), mixed-methods (n = 4) and sensors (n = 3). The Stanford Healthy Neighborhood Discovery Tool was most effective at delivering real time data collection, exploring new communication and dissemination opportunities for remote and marginalized communities, and at offering a flexible and cost-effective approach to identify health promotion interventions. Studies that implemented photovoice tools and mobile applications had challenges with regard to recruitment and retention of participants as well as privacy concerns.

Conclusions

Mobile health technologies in community-based participatory research projects may be a promising way to uncover unknown local risk factors, raise awareness and identifying targeted policy solutions to promote healthy and sustainable environments in urban spheres. The effectiveness of mobile health applications for health promotion of non-communicable diseases may vary between community-based participatory studies by data collection method.

Key messages

• Mobile health technologies in communities may be a promising way to promote healthy and sustainable environments by raising awareness and offering targeted policy solutions in urban spheres.

• The effectiveness of mobile health applications for health promotion of non-communicable diseases may vary between community-based participatory studies by data collection method.