Tracing the origin of adult intestinal stem cells.

Adult intestinal stem cells are located at the bottom of crypts of Lieberkühn, where they express markers such as LGR51,2 and fuel the constant replenishment of the intestinal epithelium1. Although fetal LGR5-expressing cells can give rise to adult intestinal stem cells3,4, it remains unclear whether this population in the patterned epithelium represents unique intestinal stem-cell precursors. Here we show, using unbiased quantitative lineage-tracing approaches, biophysical modelling and intestinal transplantation, that all cells of the mouse intestinal epithelium-irrespective of their location and pattern of LGR5 expression in the fetal gut tube-contribute actively to the adult intestinal stem cell pool. Using 3D imaging, we find that during fetal development the villus undergoes gross remodelling and fission. This brings epithelial cells from the non-proliferative villus into the proliferative intervillus region, which enables them to contribute to the adult stem-cell niche. Our results demonstrate that large-scale remodelling of the intestinal wall and cell-fate specification are closely linked. Moreover, these findings provide a direct link between the observed plasticity and cellular reprogramming of differentiating cells in adult tissues following damage5-9, revealing that stem-cell identity is an induced rather than a hardwired property.

Inhibition of WNT/ß-catenin signalling during sex-specific gonadal differentiation is essential for normal human fetal testis development.

Sex-specific gonadal differentiation is directed by complex signalling promoting development in either male or female direction, while simultaneously inhibiting the opposite pathway. In mice, the WNT/ß-catenin pathway promotes ovarian development and the importance of actively inhibiting this pathway to ensure normal testis development has been recognised. However, the implications of alterations in the tightly regulated WNT/ß-catenin signalling during human fetal gonad development has not yet been examined in detail. Thus, the aim of this study was to examine the consequences of dysregulating the WNT/ß-catenin signalling pathway in the supporting cell lineage during sex-specific human fetal gonad development using an established and extensively validated ex vivo culture model. Inhibition of WNT/ß-catenin signalling in human fetal ovary cultures resulted in only minor effects, including reduced secretion of RSPO1 and reduced cell proliferation although this was not consistently found in all treatment groups. In contrast, promotion of WNT/ß-catenin signalling in testes severely affected development and function. This included disrupted seminiferous cord structures, reduced cell proliferation, reduced expression of SOX9/AMH, reduced secretion of Inhibin B and AMH as well as loss of the germ cell population. Additionally, Leydig cell function was markedly impaired with reduced secretion of testosterone, androstenedione and INSL3. Together, this study suggests that dysregulated WNT/ß-catenin signalling during human fetal gonad development severely impairs testicular development and function. Importantly, our study highlights the notion that sufficient inhibition of the opposite pathway during sex-specific gonadal differentiation is essential to ensure normal development and function also applies to human fetal gonads.

A Novel Behavioral Intervention to Enhance Physical Activity for Older Veterans in a Skilled Nursing Facility.

Physical activity levels during skilled nursing facility (SNF) rehabilitation fall far below what is needed for successful community living and to prevent adverse events. This feasibility study's purpose was to evaluate the feasibility, acceptability, and preliminary effectiveness of an intervention designed to improve physical activity in patients admitted to SNFs for short-term rehabilitation. High-Intensity Rehabilitation plus Mobility combined a high-intensity (i.e., high weight, low repetition), progressive (increasing in difficulty over time), and functional resistance rehabilitation intervention with a behavioral economics-based physical activity program. The behavioral economics component included five mobility sessions/week with structured goal setting, gamification, and loss aversion (the idea that people are more likely to change a behavior in response to a potential loss over a potential gain). SNF physical therapists, occupational therapists, and a mobility coach implemented the High-Intensity Rehabilitation plus Mobility protocol with older Veterans (n = 18) from a single SNF. Participants demonstrated high adherence to the mobility protocol and were highly satisfied with their rehabilitation. Treatment fidelity scores for clinicians were ≥95%. We did not observe a hypothesized 40% improvement in step counts or time spent upright. However, High-Intensity Rehabilitation plus Mobility participants made clinically important improvements in short physical performance battery scores and gait speed from admission to discharge that were qualitatively similar to or slightly higher than historical cohorts from the same SNF that had received usual care or high-intensity rehabilitation alone. These results suggest a structured physical activity program can be feasibly combined with high-intensity rehabilitation for SNF residents following a hospital stay.

Identification of a window of androgen sensitivity for somatic cell function in human fetal testis cultured ex vivo.

BACKGROUND: Reduced androgen action during early fetal development has been suggested as the origin of reproductive disorders comprised within the testicular dysgenesis syndrome (TDS). This hypothesis has been supported by studies in rats demonstrating that normal male development and adult reproductive function depend on sufficient androgen exposure during a sensitive fetal period, called the masculinization programming window (MPW). The main aim of this study was therefore to examine the effects of manipulating androgen production during different timepoints during early human fetal testis development to identify the existence and timing of a possible window of androgen sensitivity resembling the MPW in rats. METHODS: The effects of experimentally reduced androgen exposure during different periods of human fetal testis development and function were examined using an established and validated human ex vivo tissue culture model. The androgen production was reduced by treatment with ketoconazole and validated by treatment with flutamide which blocks the androgen receptor. Testicular hormone production ex vivo was measured by liquid chromatography-tandem mass spectrometry or ELISA assays, and selected protein markers were assessed by immunohistochemistry. RESULTS: Ketoconazole reduced androgen production in testes from gestational weeks (GW) 7-21, which were subsequently divided into four age groups: GW 7-10, 10-12, 12-16 and 16-21. Additionally, reduced secretion of testicular hormones INSL3, AMH and Inhibin B was observed, but only in the age groups GW 7-10 and 10-12, while a decrease in the total density of germ cells and OCT4+ gonocytes was found in the GW 7-10 age group. Flutamide treatment in specimens aged GW 7-12 did not alter androgen production, but the secretion of INSL3, AMH and Inhibin B was reduced, and a reduced number of pre-spermatogonia was observed. CONCLUSIONS: This study showed that reduced androgen action during early development affects the function and density of several cell types in the human fetal testis, with similar effects observed after ketoconazole and flutamide treatment. The effects were only observed within the GW 7-14 period-thereby indicating the presence of a window of androgen sensitivity in the human fetal testis.

Prospective telehealth analysis of functional performance, frailty, quality of life, and mental health after COVID-19 hospitalization.

BACKGROUND: COVID-19 is a global pandemic with poorly understood long-term consequences. Determining the trajectory of recovery following COVID-19 hospitalization is critical for prioritizing care, allocating resources, facilitating prognosis, and informing rehabilitation. The purpose of this study was to prospectively evaluate recovery following COVID-19 hospitalization. METHODS: Participants age 18 years or older who were hospitalized for ≥24 h due to COVID-19 completed phone/video call virtual assessments (including the 10-time chair rise test) and survey forms at three time points (2-6, 12, and 18 weeks) after hospital discharge. Univariate logistic and linear regression models assessed the associations of the outcomes with primary predictors (categorical age, sex, race/ethnicity group, and categorical pre-hospitalization frailty) at baseline; the same were used to assess differences in change from week 2-6 (continuous outcomes) or outcome persistence/worsening (categorical) at last contact. RESULTS: One hundred nine adults (age 53.0 [standard deviation 13.1]; 53% female) participated including 43 (39%) age 60 or greater; 59% identified as an ethnic and/or racial minority. Over 18 weeks, the mean time to complete the 10-time chair rise test decreased (i.e., improved) by 6.0 s (95% CI: 4.1, 7.9 s; p < 0.001); this change did not differ by pre-hospital frailty, race/ethnicity group, or sex, but those age ≥ 60 had greater improvement. At weeks 2-6, 67% of participants reported a worse Clinical Frailty Scale category compared to their pre-hospitalization level, whereas 42% reported a worse frailty score at 18 weeks. Participants who did not return to pre-hospitalization levels were more likely to be female, younger, and report a pre-hospitalization category of 'very fit' or 'well'. CONCLUSIONS: We found that functional performance improved from weeks 2-6 to 18 weeks of follow-up; that incident clinical frailty developed in some individuals following COVID-19; and that age, sex, race/ethnicity, and pre-hospitalization frailty status may impact recovery from COVID-19. Notably, individuals age 60 and older were more likely than those under age 45 years to return to their pre-hospitalization status and to make greater improvements in functional performance. The results of the present study provide insight into the trajectory of recovery among a representative cohort of individuals hospitalized due to COVID-19.

The effects of selected inhibitors on human fetal adrenal steroidogenesis differs under basal and ACTH-stimulated conditions.

BACKGROUND: Disordered fetal adrenal steroidogenesis can cause marked clinical effects including virilization of female fetuses. In postnatal life, adrenal disorders can be life-threatening due to the risk of adrenal crisis and must be carefully managed. However, testing explicit adrenal steroidogenic inhibitory effects of therapeutic drugs is challenging due to species-specific characteristics, and particularly the impact of adrenocorticotropic hormone (ACTH) stimulation on drugs targeting steroidogenesis has not previously been examined in human adrenal tissue. Therefore, this study aimed to examine the effects of selected steroidogenic inhibitors on human fetal adrenal (HFA) steroid hormone production under basal and ACTH-stimulated conditions. METHODS: This study used an established HFA ex vivo culture model to examine treatment effects in 78 adrenals from 50 human fetuses (gestational weeks 8-12). Inhibitors were selected to affect enzymes critical for different steps in classic adrenal steroidogenic pathways, including CYP17A1 (Abiraterone acetate), CYP11B1/2 (Osilodrostat), and a suggested CYP21A2 inhibitor (Efavirenz). Treatment effects were examined under basal and ACTH-stimulated conditions in tissue from the same fetus and determined by quantifying the secretion of adrenal steroids in the culture media using liquid chromatography-tandem mass spectrometry. Statistical analysis was performed on ln-transformed data using one-way ANOVA for repeated measures followed by Tukey's multiple comparisons test. RESULTS: Treatment with Abiraterone acetate and Osilodrostat resulted in potent inhibition of CYP17A1 and CYP11B1/2, respectively, while treatment with Efavirenz reduced testosterone secretion under basal conditions. ACTH-stimulation affected the inhibitory effects of all investigated drugs. Thus, treatment effects of Abiraterone acetate were more pronounced under stimulated conditions, while Efavirenz treatment caused a non-specific inhibition on steroidogenesis. ACTH-stimulation prevented the Osilodrostat-mediated CYP11B1 inhibition observed under basal conditions. CONCLUSIONS: Our results show that the effects of steroidogenic inhibitors differ under basal and ACTH-stimulated conditions in the HFA ex vivo culture model. This could suggest that in vivo effects of therapeutic drugs targeting steroidogenesis may vary in conditions where patients have suppressed or high ACTH levels, respectively. This study further demonstrates that ex vivo cultured HFAs can be used to evaluate steroidogenic inhibitors and thereby provide novel information about the local effects of existing and emerging drugs that targets steroidogenesis.

Targeted Rhesus immunoglobulin for RhD-negative women undergoing an induced abortion: A clinical pilot study.

INTRODUCTION: The aim of this clinical pilot study was to examine the accuracy of noninvasive fetal RHD genotyping in early pregnancy (8+0  to 11+6  weeks) and to clarify whether targeted administration of Rhesus immunoglobulin (RhIg) is possible for women undergoing an induced abortion such that unnecessary injections can be avoided. The study examines the correlation between gestational age and the amount of cell-free fetal DNA in maternal plasma, the fetal fraction of DNA and whether transportation time or body mass index affects these parameters. MATERIAL AND METHODS: Fifty-two RhD-negative women undergoing a surgically induced abortion were included. A maternal blood sample was collected prior to the abortion and a tissue sample was collected from the placental part of the abortion material after the intervention. Fetal RhD type was determined by PCR analysis of cell-free fetal DNA extracted from maternal plasma and on DNA from the tissue sample, with the latter providing a reference standard. Copies of RHD/mL were determined on RHD-positive samples and the fetal fraction of DNA was calculated. RESULTS: We demonstrated complete concordance between results from plasma and tissue, with 31 RhD-positive and 21 RhD-negative samples, corresponding to 40% being RhD-negative, specificity 100% [95% confidence interval (CI) 88.8-100] and sensitivity 100% (95% CI 83.9-100). We found no significant correlation between gestational age and the amount or the fraction of cell-free fetal DNA in maternal plasma, nor did we find that transportation time or BMI significantly affected these factors in this setup. CONCLUSIONS: Fetal RHD genotyping can be accurately performed from the 8th week of gestation and unnecessary injections of RhIg can be avoided for women undergoing an induced abortion. A larger study is needed to determine a more accurate sensitivity for the analysis early in pregnancy.

Postprandial gut hormone responses and glucose metabolism in cholecystectomized patients.

Preclinical studies suggest that gallbladder emptying, via bile acid-induced activation of the G protein-coupled receptor TGR5 in intestinal L cells, may play a significant role in the secretion of the incretin hormone glucagon-like peptide-1 (GLP-1) and, hence, postprandial glucose homeostasis. We examined the secretion of gut hormones in cholecystectomized subjects to test the hypothesis that gallbladder emptying potentiates postprandial release of GLP-1. Ten cholecystectomized subjects and 10 healthy, age-, gender-, and body mass index-matched control subjects received a standardized fat-rich liquid meal (2,200 kJ). Basal and postprandial plasma concentrations of glucose, insulin, C-peptide, glucagon, GLP-1, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-2 (GLP-2), cholecystokinin (CCK), and gastrin were measured. Furthermore, gastric emptying and duodenal and serum bile acids were measured. We found similar basal glucose concentrations in the two groups, whereas cholecystectomized subjects had elevated postprandial glucose excursions. Cholecystectomized subjects had reduced postprandial concentrations of duodenal bile acids, but preserved postprandial plasma GLP-1 responses, compared with control subjects. Also, cholecystectomized patients exhibited augmented fasting glucagon. Basal plasma CCK concentrations were lower and peak concentrations were higher in cholecystectomized patients. The concentrations of GIP, GLP-2, and gastrin were similar in the two groups. In conclusion, cholecystectomized subjects had preserved postprandial GLP-1 responses in spite of decreased duodenal bile delivery, suggesting that gallbladder emptying is not a prerequisite for GLP-1 release. Cholecystectomized patients demonstrated a slight deterioration of postprandial glycemic control, probably because of metabolic changes unrelated to incretin secretion.

Using Wearable Technology to Quantify Physical Activity Recovery: Secondary Report From the AFTER (App-Facilitated Tele-Rehabilitation) Program for COVID-19 Survivors Randomized Study.

BACKGROUND: Knowledge on physical activity recovery after COVID-19 survival is limited. The AFTER (App-Facilitated Tele-Rehabilitation) program for COVID-19 survivors randomized participants, following hospital discharge, to either education and unstructured physical activity or a telerehabilitation program. Step count data were collected as a secondary outcome, and we found no significant differences in total step count trajectories between groups at 6 weeks. Further step count data were not analyzed. OBJECTIVE: The purpose of this analysis was to examine step count trajectories and correlates among all participants (combined into a single group) across the 12-week study period. METHODS: Linear mixed models with random effects were used to model daily steps over the number of study days. Models with 0, 1, and 2 inflection points were considered, and the final model was selected based on the highest log-likelihood value. RESULTS: Participants included 44 adults (41 with available Fitbit [Fitbit LLC] data). Initially, step counts increased by an average of 930 (95% CI 547-1312; P<.001) steps per week, culminating in an average daily step count of 7658 (95% CI 6257-9059; P<.001) at the end of week 3. During the remaining 9 weeks of the study, weekly step counts increased by an average of 67 (95% CI -30 to 163; P<.001) steps per week, resulting in a final estimate of 8258 (95% CI 6933-9584; P<.001) steps. CONCLUSIONS: Participants showed a marked improvement in daily step counts during the first 3 weeks of the study, followed by more gradual improvement in the remaining 9 weeks. Physical activity data and step count recovery trajectories may be considered surrogates for physiological recovery, although further research is needed to examine this relationship. TRIAL REGISTRATION: ClinicalTrials.gov NCT04663945; https://tinyurl.com/2p969ced.

Dexamethasone affects human fetal adrenal steroidogenesis and subsequent ACTH response in an ex vivo culture model.

Introduction: Administration of dexamethasone (DEX) has been used experimentally to suppress androgenization of external genitalia in 46,XX fetuses with congenital adrenal hyperplasia. Despite this, the prenatal biological mechanism-of-action of DEX on fetal development is not known. This study aimed to examine direct effects of DEX on human fetal adrenal (HFA) steroidogenic activity including possible effects on the subsequent response to ACTH-stimulation. Methods: Human fetal adrenal (HFA) tissue from 30 fetuses (1st trimester) were cultured ex vivo with A) DEX (10 µm) for 14 days, or B) DEX (10 µm) for 10 days followed by ACTH (1 nM) for 4 days. DEX-mediated effects on HFA morphology, viability, and apoptosis (immunohistochemistry), gene expression (quantitative PCR), and steroid hormone secretion (LC-MS/MS) were investigated. Results: DEX-treatment caused decreased androstenedione (p<0.05) and increased cortisol (p<0.01) secretion suggesting that direct effects on the adrenal gland may contribute to the negative feedback on the hypothalamic-pituitary-adrenal axis in vivo. An altered response to ACTH stimulation in HFA pre-treated with DEX included increased androgen (p<0.05) and reduced cortisol production (p<0.05), supporting clinical observations of a temporary decreased ACTH-response following prenatal DEX-treatment. Additionally, the secretion of corticosterone was decreased (p<0.0001) following ACTH-stimulation in the initially DEX-treated HFAs. Discussion: The observed effects suggest that prenatal DEX-treatment can cause direct effects on HFA steroidogenesis and in the subsequent response to ACTH-stimulation. This may indicate a requirement for careful monitoring of adrenal function in prenatally DEX-treated neonates, with particular focus on their mineralocorticoid levels.

Signs of a Glucose- and Insulin-Independent Gut-Bone Axis and Aberrant Bone Homeostasis in Type 1 Diabetes.

CONTEXT: Gut hormones seem to play an important role in postprandial bone turnover, which also may be affected by postprandial plasma glucose excursions and insulin secretion. OBJECTIVE: To investigate the effect of an oral glucose tolerance test (OGTT) and an isoglycemic intravenous glucose infusion (IIGI) on bone resorption and formation markers in individuals with type 1 diabetes and healthy controls. METHODS: This observational case-control study, conducted at the Center for Clinical Metabolic Research, Gentofte Hospital, Hellerup, Denmark, included 9 individuals with C-peptide negative type 1 diabetes and 8 healthy controls matched for gender, age, and body mass index. Subjects underwent an OGTT and a subsequent IIGI. We analyzed changes in bone resorption assessed by measurements of carboxy-terminal type I collagen crosslinks (CTX) and in bone formation as assessed by procollagen type I N-terminal propeptide (PINP) concentrations. RESULTS: Baseline CTX and PINP levels were similar in the 2 groups. Both groups exhibited significantly greater suppression of CTX during OGTT than IIGI. PINP levels were unaffected by OGTT and IIGI, respectively, in healthy controls. Participants with type 1 diabetes displayed impaired suppression of CTX-assessed bone resorption and inappropriate suppression of PINP-assessed bone formation during OGTT. CONCLUSION: Our data suggest the existence of a gut-bone axis reducing bone resorption in response to oral glucose independently of plasma glucose excursions and insulin secretion. Subjects with type 1 diabetes showed impaired suppression of bone resorption and reduced bone formation during OGTT, which may allude to the reduced bone mineral density and increased fracture risk characterizing these individuals.

Safety, feasibility and initial efficacy of an app-facilitated telerehabilitation (AFTER) programme for COVID-19 survivors: a pilot randomised study.

OBJECTIVES: Determine the safety, feasibility and initial efficacy of a multicomponent telerehabilitation programme for COVID-19 survivors. DESIGN: Pilot randomised feasibility study. SETTING: In-home telerehabilitation. PARTICIPANTS: 44 participants (21 female, mean age 52 years) discharged home following hospitalisation with COVID-19 (with and without intensive care unit (ICU) stay). INTERVENTIONS: Participants were block randomised 2:1 to receive 12 individual biobehaviourally informed, app-facilitated, multicomponent telerehabilitation sessions with a licenced physical therapist (n=29) or to a control group (n=15) consisting of education on exercise and COVID-19 recovery trajectory, physical activity and vitals monitoring, and weekly check-ins with study staff. Interventions were 100% remote and occurred over 12 weeks. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was feasibility, including safety and session adherence. Secondary outcomes included preliminary efficacy outcomes including tests of function and balance; patient-reported outcome measures; a cognitive assessment; and average daily step count. The 30 s chair stand test was the main secondary (efficacy) outcome. RESULTS: No adverse events (AEs) occurred during testing or in telerehabilitation sessions; 38% (11/29) of the intervention group compared with 60% (9/15) of the control group experienced an AE (p=0.21), most of which were minor, over the course of the 12-week study. 27 of 29 participants (93%; 95% CI 77% to 99%) receiving the intervention attended ≥75% of sessions. Both groups demonstrated clinically meaningful improvement in secondary outcomes with no statistically significant differences between groups. CONCLUSION: Fully remote telerehabilitation was safe, feasible, had high adherence for COVID-19 recovery, and may apply to other medically complex patients including those with barriers to access care. This pilot study was designed to evaluate feasibility; further efficacy evaluation is needed. TRIAL REGISTRATION NUMBER: NCT04663945.

Establishment of a Novel Human Fetal Adrenal Culture Model that Supports de Novo and Manipulated Steroidogenesis.

CONTEXT: Disorders affecting adrenal steroidogenesis promote an imbalance in the normally tightly controlled secretion of mineralocorticoids, glucocorticoids, and androgens. This may lead to differences/disorders of sex development in the fetus, as seen in virilized girls with congenital adrenal hyperplasia (CAH). Despite the important endocrine function of human fetal adrenals, neither normal nor dysregulated adrenal steroidogenesis is understood in detail. OBJECTIVE: Due to significant differences in adrenal steroidogenesis between human and model species (except higher primates), we aimed to establish a human fetal adrenal model that enables examination of both de novo and manipulated adrenal steroidogenesis. DESIGN AND SETTING: Human adrenal tissue from 54 1st trimester fetuses were cultured ex vivo as intact tissue fragments for 7 or 14 days. MAIN OUTCOME MEASURES: Model validation included examination of postculture tissue morphology, viability, apoptosis, and quantification of steroid hormones secreted to the culture media measured by liquid chromatography-tandem mass spectrometry. RESULTS: The culture approach maintained cell viability, preserved cell populations of all fetal adrenal zones, and recapitulated de novo adrenal steroidogenesis based on continued secretion of steroidogenic intermediates, glucocorticoids, and androgens. Adrenocorticotropic hormone and ketoconazole treatment of ex vivo cultured human fetal adrenal tissue resulted in the stimulation of steroidogenesis and inhibition of androgen secretion, respectively, demonstrating a treatment-specific response. CONCLUSIONS: Together, these data indicate that ex vivo culture of human fetal adrenal tissue constitutes a novel approach to investigate local effects of pharmaceutical exposures or emerging therapeutic options targeting imbalanced steroidogenesis in adrenal disorders, including CAH.

A 3D system to model human pancreas development and its reference single-cell transcriptome atlas identify signaling pathways required for progenitor expansion.

Human organogenesis remains relatively unexplored for ethical and practical reasons. Here, we report the establishment of a single-cell transcriptome atlas of the human fetal pancreas between 7 and 10 post-conceptional weeks of development. To interrogate cell-cell interactions, we describe InterCom, an R-Package we developed for identifying receptor-ligand pairs and their downstream effects. We further report the establishment of a human pancreas culture system starting from fetal tissue or human pluripotent stem cells, enabling the long-term maintenance of pancreas progenitors in a minimal, defined medium in three-dimensions. Benchmarking the cells produced in 2-dimensions and those expanded in 3-dimensions to fetal tissue identifies that progenitors expanded in 3-dimensions are transcriptionally closer to the fetal pancreas. We further demonstrate the potential of this system as a screening platform and identify the importance of the EGF and FGF pathways controlling human pancreas progenitor expansion.

Inappropriate glucagon response after oral compared with isoglycemic intravenous glucose administration in patients with type 1 diabetes.

Hyperglucagonemia following oral glucose ingestion in patients with type 1 diabetes (and type 2 diabetes) has been claimed to result from impaired intraislet insulin inhibition of glucagon. We looked at plasma glucagon responses to the oral glucose tolerance test (OGTT) and isoglycemic intravenous glucose infusion (IIGI) in patients with type 1 diabetes. Nine patients without residual beta-cell function [age: 25 +/- 9 yr; body mass index (BMI): 24 +/- 2 kg/m(2); fasting plasma glucose (FPG): 9.5 +/- 2.1 mM; Hb A(1c): 8.4 +/- 1.2% (mean +/- SD)] and eight healthy subjects (age: 28 +/- 5 yr; BMI: 24 +/- 3 kg/m(2); FPG: 5.3 +/- 0.2 mM; Hb A(1c): 5.0 +/- 0.1%) were examined on two separate occasions: 4-h 50-g OGTT and IIGI. Isoglycemia during IIGIs was obtained using 53 +/- 5 g of glucose in patients with type 1 diabetes and 30 +/- 3 g in control subjects (P < 0.001), resulting in gastrointestinal-mediated glucose disposal [100% x (glucose(OGTT) - glucose(IIGI)/glucose(OGTT))] of -6 +/- 9 and 40 +/- 6% (P < 0.01), respectively. Equal glucagon suppression during the two glucose stimuli was observed in healthy subjects, whereas patients with type 1 diabetes exhibited less inhibition in response to OGTT compared with IIGI (AUC: 1,519 +/- 129 vs. 1,240 +/- 86 pM.4 h; P = 0.03). This difference was even more pronounced during the initial 40 min with paradoxical hypersecretion of glucagon during OGTT and suppression during IIGI (AUC: 37 +/- 13 vs. -33 +/- 16 pM.40 min; P = 0.02). These results suggest that the inappropriate glucagon response to glucose in patients with type 1 diabetes occurs as a consequence of the oral administration way, suggesting a role of the gastrointestinal tract, possibly via glucagonotropic signaling from gut hormones (e.g., glucose-dependent insulinotropic polypeptide), in type 1 diabetic hyperglucagonemia.

On the role of glucose-dependent insulintropic polypeptide in postprandial metabolism in humans.

We investigated the role of glucose-dependent insulintropic polypeptide (GIP) in the regulation of gastric emptying (GE), appetite, energy intake (EI), energy expenditure (EE), plasma levels of triglycerides (TAG), and free fatty acids (FFA) in humans. First, 20 healthy males received intravenous infusion of GIP (0.8 pmol.kg(-1).min(-1)) or saline for 300 min during and after a fixed meal (protocol 1). GE was measured using paracetamol, appetite sensations using visual analog scales, EE using indirect calorimetry, and EI during a subsequent ad libitum meal (at 300 min). Next, 10 healthy males received intravenous infusions of Intralipid, glucose, or Intralipid plus glucose, with and without GIP (1.5 pmol.kg(-1).min(-1)) for 300 min (protocol 2). In protocol 1, GIP did not have any effect on GE, EI, EE, removal of TAG, or FFA and did not influence the subjective feeling of hunger, satiety, fullness or prospective food consumption compared with saline. In protocol 2, no difference was seen in the plasma TAG on Intralipid + GIP/saline and Intralipid + glucose + GIP/saline days. FFA concentrations were lower on Intralipid + glucose + GIP/saline days (P < 0.05) compared with Intralipid + GIP/saline days and on Intralipid + GIP day (P < 0.004) compared with Intralipid + saline day. Insulin increased on all GIP days compared with saline days (P < 0.05). In conclusion, while confirming its insulinotropic effects, these data suggest that GIP does not affect GE, appetite, energy intake, EE, or the clearance rate of the applied TAG formulation in humans. However, both insulin and GIP lower post-Intralipid FFA concentration, GIP probably via stimulation of insulin secretion, increasing FFA reesterification.

The intestinotrophic peptide, GLP-2, counteracts the gastrointestinal atrophy in mice induced by the epidermal growth factor receptor inhibitor, erlotinib, and cisplatin.

PURPOSE: Erlotinib, an epidermal-growth-factor receptor inhibitor, belongs to a new generation of targeted cancer therapeutics. Gastrointestinal side-effects are common and have been markedly aggravated when erlotinib is combined with cytostatics. We examined the effects of erlotinib alone and combined with the cytostatic, cisplatin, on the gastrointestinal tract and examined whether glucagon-like peptide-2 (GLP-2), an intestinal hormone with potent intestinotrophic properties, might counteract the possible damaging effects of the treatments. EXPERIMENTAL DESIGN: Groups of ten mice were treated for 10 days with increasing doses of erlotinib alone or in combination with cisplatin and/or GLP-2. Weight and length of the gastrointestinal organs were determined and histological sections were analyzed with morphometric methods as well as BrdU- and ApopTag-staining to determine mitotic and apoptotic activity. RESULTS: Erlotinib was found to induce small-intestinal and colonic growth inhibition through an increased apoptotic activity but had no effect on mitotic activity. The combined treatment with cisplatin synergistically aggravated the intestinal growth inhibition. Erlotinib, and especially the combination therapy, increased the weight of the stomach contents considerably. Concomitant treatment with GLP-2 counteracted the intestinal mucosal atrophy induced both by erlotinib alone and combined with cisplatin through a reduction of the apoptotic activity. There was no influence on the mitotic activity. CONCLUSIONS: The findings demonstrate that the intestinal mucosal damage induced by erlotinib alone and in combination with cisplatin can be counteracted by GLP-2 treatment, which might suggest a role for GLP-2 in the treatment of the gastrointestinal side-effects caused by these cancer therapeutics.

Role of GLP-1 induced glucagon suppression in type 2 diabetes mellitus.

This project consisted of two parts: a biochemical part and clinical studies. The overall aim was to elucidate the defective regulation of glucagon secretion in type 2 diabetes (T2DM). The aim in the biochemical part was to develop a glucagon ELISA by using C- and N-terminal antibodies generated in the laboratory. Much effort was put into this attempt; however, we were unsuccessful and had to use an alternative method in our attempt to characterize the paradoxical diabetic glucagon response further. By using Sep-Pac and HPLC separation methods, plasma from patients with T2DM known to have a defective suppression of glucagon was analyzed using three antibodies and RIA. In this way the hyperglucagonaemia was found to consist mainly of authentic glucagon, rather than abnormally processed forms. The first clinical study included ten healthy controls matched to ten patients with T2DM. The aim was to investigate if GLP-1 induced glucagon inhibition was dose dependent and if suppression was equally potent in healthy controls and T2DM patients. Further, we investigated if the potency of the inhibition depended on the prevailing plasma glucose (PG) level. All participants were investigated with increasing doses of GLP-1 administered as iv-infusions and saline (control) during a glycaemic clamp at fasting plasma glucose (FPG) levels. Patients were investigated on a third occasion with GLP-1 infusions after an over-night normalisation of PG using adjustable insulin infusions. From these experiments we were able to conclude that GLP-1-induced glucagon inhibition is dose-dependent, but surprisingly GLP-1 suppressed the alpha cell equally potently in patients and controls - and the suppression was independent of PG level. Therefore we concluded that the paradoxical glucagon response to orally ingested glucose is not caused by decreased potency of GLP-1 with respect to glucagon suppression. It may be due to the decreased secretion of this hormone reported in earlier studies. My second protocol aimed towards quantifying the glucose-lowering effect of GLP-1-induced glucagon inhibition seen in patients with T2DM. The glucose-lowering effect of GLP-1 is due to both insulin stimulation leading to peripheral glucose disposal and glucagon inhibition resulting in decreased stimulation of hepatic glucose production. With a five-day protocol including both glycaemic and pancreatic clamps in ten patients with T2DM we were able to isolate the contribution of glucagon suppression to the increased glucose turn-over seen during a GLP-1-glycaemic clamp, and interestingly it was equal to the known insulinotropic effect of GLP-1. Finally, we investigated patients with type 1 diabetes (T1DM) and no residual beta cell function with oral glucose tolerance test (OGTT) and isoglycaemic intravenous glucose infusion (IIGI) in order to evaluate any differences in glucagon response to glucose +/- gastri-intestinal (GI)-stimulation. Here we found that despite a perfectly normal inhibition of glucagon during the IIGI in the T1DM, they had a defective glucagon suppression in response to orally ingested glucose and a paradoxical secretion of glucagon was seen as in T2DM. Hereby, we proved that glucagon suppression in response to hyperglycaemia does not entirely depend on intra-islet insulin effects as has been suggested. Therefore we conclude that GI-tract factors rather than intraislet dysregulation explain the paradoxical glucagon response in patients with diabetes.

Endometrial scratch injury with office hysteroscopy before IVF/ICSI: A randomised controlled trial.

OBJECTIVE: Endometrial scratch injury (ESI) has been proposed to improve endometrial receptivity and thereby increase implantation rates in assisted reproductive technology (ART) treatment. ESI has been widely incorporated into clinical practice despite inconclusive evidence of its effect on reproductive outcomes. We aimed to assess pregnancy and live birth rates in subfertile women receiving ESI before IVF treatment in comparison to controls. STUDY DESIGN: This was a randomised controlled trial (RCT) with no blinding of participants, investigators or health care personnel. Women in ART treatment were allocated to either office hysteroscopy with ESI (ESI group) or no intervention (control group). In total 184 women in IVF/ICSI treatment with minimum one previous failed IVF/ICSI cycle, were included in the final analysis. The primary outcome was positive serum hCG (s-hCG). Secondary outcomes were ongoing pregnancy and live birth rate. Only per-protocol analyses were performed as all patients included at one centre had to be excluded. The trial is registered at ClinicalTrials.gov, NCT01743391. RESULTS: Our results showed a non-significant increase in positive s-hCG (OR 1.23, 95 % CI (0.65-2.33)), ongoing pregnancy (OR 1.52, 95 % CI (0.73-3.17)), and live birth rates (OR 1.69, 95 % CI (0.78-3.64)) per randomised woman between the ESI and the control group. CONCLUSION: We observed no significant differences in positive s-hCG or other reproductive outcomes in the ESI vs. the control group. While the crude estimates of positive reproductive outcomes were higher in the ESI group, statistical significance was not reached, and the study was not powered to show smaller differences. However, data from this study will be re-evaluated in the context of an individual participant data meta-analysis (IPD-MA) of RCTs on ESI.

Secretion of parathyroid hormone may be coupled to insulin secretion in humans.

OBJECTIVE: Parathyroid hormone (PTH) is a key hormone in regulation of calcium homeostasis and its secretion is regulated by calcium. Secretion of PTH is attenuated during intake of nutrients, but the underlying mechanism(s) are unknown. We hypothesized that insulin acts as an acute regulator of PTH secretion. METHODS: Intact PTH was measured in plasma from patients with T1D and matched healthy individuals during 4-h oral glucose tolerance tests (OGTT) and isoglycemic i.v. glucose infusions on 2 separate days. In addition, expression of insulin receptors on surgical specimens of parathyroid glands was assessed by immunochemistry (IHC) and quantitative PCR (qPCR). RESULTS: The inhibition of PTH secretion was more pronounced in healthy individuals compared to patients with T1D during an OGTT (decrementalAUC0-240min: -5256 ± 3954 min × ng/L and -2408 ± 1435 min × ng/L, P = 0.030). Insulin levels correlated significantly and inversely with PTH levels, also after adjusting for levels of several gut hormones and BMI (P = 0.002). Expression of insulin receptors in human parathyroid glands was detected by both IHC and qPCR. CONCLUSION: Our study suggests that insulin may act as an acute regulator of PTH secretion in humans.