Moris, Demetrios MD, PhD, MACS; Felekouras, Evangelos MD, PhD; Chrousos, George P. MD, MACP, MACE, PhD Author Information
Brain organoids are three-dimensional cultures that contain multiple types of cells and cytoarchitectures, and resemble fetal human brain structurally and functionally. These organoids are being used increasingly to model brain development and disorders, however, they only partially recapitulate such processes, because of several limitations, including inability to mimic the distinct cortical layers, lack of functional neuronal circuitry as well as non-neural cells and gyrification, and increased cellular stress. Efforts to create improved brain organoid culture systems have led to region-specific organoids, vascularized organoids, glia-containing organoids, assembloids, sliced organoids and polarized organoids. Assembloids are fused region-specific organoids, which attempt to recapitulate inter-regional and inter-cellular interactions as well as neural circuitry development by combining multiple brain regions and/or cell lineages. As a result, assembloids can be used to model subtle functional aberrations that reflect complex neurodevelopmental, neuropsychiatric and neurodegenerative disorders. Mammalian organisms possess a highly complex neuroendocrine system, the stress system, whose main task is the preservation of systemic homeostasis, when the latter is threatened by adverse forces, the stressors. The main central parts of the stress system are the paraventricular nucleus of the hypothalamus and the locus caeruleus/norepinephrine-autonomic nervous system nuclei in the brainstem; these centers innervate each other and interact reciprocally as well as with various other CNS structures. Chronic dysregulation of the stress system has been implicated in major pathologies, the so-called chronic non-communicable diseases, including neuropsychiatric, neurodegenerative, cardiometabolic and autoimmune disorders, which lead to significant population morbidity and mortality. We speculate that brain organoids and/or assembloids could be used to model the development, regulation and dysregulation of the stress system and to better understand stress-related disorders. Novel brain organoid technologies, combined with high-throughput single-cell omics and gene editing, could, thus, have major implications for precision medicine.
Abstract Background Childhood obesity represents a major health problem of our century. The benefits of natural products, such as honey, in the management of obesity have gained renewed interest. In this study, we investigated the effect of honey on glucose and insulin concentrations in obese prepubertal girls. Materials and Methods Thirty healthy obese girls aged 10.55 (± SEM :0.34) years with a mean body mass index ( BMI ) above the 97th centile for age (28.58 ± 1.40 kg/m 2 , BMI z ‐score 2.96) underwent a standard oral glucose tolerance test ( OGTT ) followed by an oral honey tolerance test ( OHTT ) 2 weeks later. Both solutions contained 75 g of glucose. Subsequently, subjects were randomized to receive either 15 g of honey or 15 g of marmalade daily, while both groups complied with dietetic instructions. Six months later all subjects were re‐evaluated with an OGTT and an OHTT . Results At the end of the study, all subjects demonstrated a significant reduction in BMI (27.57 ± 1.40, z ‐score: 2.54 vs 28.58 ± 1.40 kg/m 2 , z ‐score: 2.96, P < 0.001), however, there were no significant differences in BMI and all parameters tested between the group that received honey and the control group. The areas under the concentration–time curve for glucose and insulin for the entire population were significantly lower following ingestion of honey than glucose solution ( P < 0.001) both at the beginning and at the end of study. Conclusions These findings indicate that honey does not have an effect on stimulated plasma glucose and serum insulin concentrations compared with the standard glucose solution in obese prepubertal girls.
Stress exposure is highly prevalent in the general population; however, the experience of stress during vulnerable periods of development has substantial and permanent effects on brain structure and function and physical health in adulthood. Stress, the state of threatened homeostasis, is generally associated with a time-limited activation of the stress system, i.e., the hypothalamic-pituitary-adrenal axis and the arousal/sympathetic nervous system, tailored to the stressful stimulus also known as the stressor. On the other hand, chronic stress may be associated with lingering hyper- or hyposecretion of mediators of the stress system. This chronic condition is called dyshomeostasis, allostasis, or cacostasis and is associated with increased mental and physical morbidity in the long term. Stressful or traumatic experiences during fetal life, early childhood, and adolescence have been related to persistent neuroendocrine and epigenetic changes. Further, brain structures involved in the stress response, such as those of the stress system, the hippocampus, and the amygdala, may be programmed early on for a life of adversity.
This project has received funding from the European Unions Horizon 2020 research and innovation programme under grant agreement No 769129.