Cardiac Remodeling After Hypertensive Pregnancy Following Physician-Optimized Blood Pressure Self-Management: The POP-HT Randomized Clinical Trial Imaging Substudy.

BACKGROUND: Hypertensive pregnancy disorders are associated with adverse cardiac remodeling, which can fail to reverse in the postpartum period in some women. The Physician-Optimized Postpartum Hypertension Treatment trial demonstrated that improved blood pressure control while the cardiovascular system recovers postpartum associates with persistently reduced blood pressure. We now report the effect on cardiac remodeling. METHODS: In this prospective, randomized, open-label, blinded end point trial, in a single UK hospital, 220 women were randomly assigned 1:1 to self-monitoring with research physician-optimized antihypertensive titration or usual postnatal care from a primary care physician and midwife. Participants were 18 years of age or older, with preeclampsia or gestational hypertension, requiring antihypertensives on hospital discharge postnatally. Prespecified secondary cardiac imaging outcomes were recorded by echocardiography around delivery, and again at blood pressure primary outcome assessment, around 9 months postpartum, when cardiovascular magnetic resonance was also performed. RESULTS: A total of 187 women (101 intervention; 86 usual care) underwent echocardiography at baseline and follow-up, at a mean 258±14.6 days postpartum, of which 174 (93 intervention; 81 usual care) also had cardiovascular magnetic resonance at follow-up. Relative wall thickness by echocardiography was 0.06 (95% CI, 0.07-0.05; P<0.001) lower in the intervention group between baseline and follow-up, and cardiovascular magnetic resonance at follow-up demonstrated a lower left ventricular mass (-6.37 g/m2; 95% CI, -7.99 to -4.74; P<0.001), end-diastolic volume (-3.87 mL/m2; 95% CI, -6.77 to -0.98; P=0.009), and end-systolic volume (-3.25 mL/m2; 95% CI, 4.87 to -1.63; P<0.001) and higher left and right ventricular ejection fraction by 2.6% (95% CI, 1.3-3.9; P<0.001) and 2.8% (95% CI, 1.4-4.1; P<0.001), respectively. Echocardiography-assessed left ventricular diastolic function demonstrated a mean difference in average E/E' of 0.52 (95% CI, -0.97 to -0.07; P=0.024) and a reduction in left atrial volumes of -4.33 mL/m2 (95% CI, -5.52 to -3.21; P<0.001) between baseline and follow-up when adjusted for baseline differences in measures. CONCLUSIONS: Short-term postnatal optimization of blood pressure control after hypertensive pregnancy, through self-monitoring and physician-guided antihypertensive titration, associates with long-term changes in cardiovascular structure and function, in a pattern associated with more favorable cardiovascular outcomes. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04273854.

Long-Term Blood Pressure Control After Hypertensive Pregnancy Following Physician-Optimized Self-Management: The POP-HT Randomized Clinical Trial.

Importance: Pregnancy hypertension results in adverse cardiac remodeling and higher incidence of hypertension and cardiovascular diseases in later life. Objective: To evaluate whether an intervention designed to achieve better blood pressure control in the postnatal period is associated with lower blood pressure than usual outpatient care during the first 9 months postpartum. Design, Setting, and Participants: Randomized, open-label, blinded, end point trial set in a single hospital in the UK. Eligible participants were aged 18 years or older, following pregnancy complicated by preeclampsia or gestational hypertension, requiring antihypertensive medication postnatally when discharged. The first enrollment occurred on February 21, 2020, and the last follow-up, November 2, 2021. The follow-up period was approximately 9 months. Interventions: Participants were randomly assigned 1:1 to self-monitoring along with physician-optimized antihypertensive titration or usual postnatal care. Main Outcomes and Measures: The primary outcome was 24-hour mean diastolic blood pressure at 9 months postpartum, adjusted for baseline postnatal blood pressure. Results: Two hundred twenty participants were randomly assigned to either the intervention group (n = 112) or the control group (n = 108). The mean (SD) age of participants was 32.6 (5.0) years, 40% had gestational hypertension, and 60% had preeclampsia. Two hundred participants (91%) were included in the primary analysis. The 24-hour mean (SD) diastolic blood pressure, measured at 249 (16) days postpartum, was 5.8 mm Hg lower in the intervention group (71.2 [5.6] mm Hg) than in the control group (76.6 [5.7] mm Hg). The between-group difference was -5.80 mm Hg (95% CI, -7.40 to -4.20; P < .001). Similarly, the 24-hour mean (SD) systolic blood pressure was 6.5 mm Hg lower in the intervention group (114.0 [7.7] mm Hg) than in the control group (120.3 [9.1] mm Hg). The between-group difference was -6.51 mm Hg (95% CI, -8.80 to -4.22; P < .001). Conclusions and Relevance: In this single-center trial, self-monitoring and physician-guided titration of antihypertensive medications was associated with lower blood pressure during the first 9 months postpartum than usual postnatal outpatient care in the UK. Trial Registration: ClinicalTrials.gov Identifier: NCT04273854.

Effects of environmental impact labels on the sustainability of food purchases: Two randomised controlled trials in an experimental online supermarket.

Providing consumers with product-specific environmental impact information for food products (ecolabels) may promote more sustainable purchasing, needed to meet global environmental targets. Two UK studies investigated the effectiveness of different ecolabels using an experimental online supermarket platform. Study 1 (N = 1051 participants) compared three labels against control (no label), while Study 2 (N = 4979) tested four designs against control. Study 1 found significant reductions in the environmental impact score (EIS) for all labels compared to control (labels presented: values for four environmental indicators [-3.9 percentiles, 95%CIs: -5.2,-2.6]; a composite score [taking values from A to E; -3.9, 95%CIs: -5.2,-2.5]; or both together [-3.2, 95%CIs: -4.5,-1.9]). Study 2 showed significant reductions in EIS compared to control for A-E labels [-2.3, 95%CIs: -3.0,-1.5], coloured globes with A-E scores [-3.2, 95%CIs:-3.9,-2.4], and red globes highlighting 'worse' products [-3.2, 95%CIs:-3.9,-2.5]. There was no evidence that green globes highlighting 'better' products were effective [-0.5, 95%CIs:-1.3,0.2]. Providing ecolabels is a promising intervention to promote the selection of more sustainable products.

Oxford Food and Activity Behaviors 20-item questionnaire to assess personal weight management strategies: Development and testing.

OBJECTIVE: The aim of this study was to develop a shortened Oxford Food and Activity Behaviors (OxFAB) questionnaire to identify the cognitive and behavioral strategies used by individuals during weight-management attempts. METHODS: This study reduced an existing 117-item questionnaire (the original OxFAB questionnaire) through identifying clusters of techniques from the responses of 278 people living with obesity and, within those clusters, identifying the most representative question or questions. Questions were rephrased to cover multiple strategies at the domain level, with several alternative phrasings developed for new questions. Face validity was tested through think-aloud interviews with 12 people living with obesity. Questions were rephrased accordingly and tested using test-retest (n = 172). Prevalence- and bias-adjusted κ (PABAK) were calculated, and questions with PABAK < 0.41 were rewritten and evaluated in a new test-retest sample (n = 130). RESULTS: OxFAB20 consists of 20 questions covering diet, physical activity, and cognitive strategies for weight management. Test-retest resulted in a mean PABAK score of 0.56 (SD = 0.14). Questions were revised where appropriate. The questionnaire is available for use via a CC-BY license. CONCLUSIONS: The OxFAB20 questionnaire provides a practical tool for researchers to identify the cognitive and behavioral strategies used by individuals during attempts at weight control.

Donor age significantly influences the Raman spectroscopic biomolecular fingerprint of human pancreatic extracellular matrix proteins following collagenase-based digestion.

Despite the enormous advances in the field of clinical pancreatic islet transplantation over the past two decades, the human islet isolation procedure remains suboptimal. Islets are extracted (isolated) from the exocrine tissue of donor pancreases using neutral protease (NP) and collagenase-based enzymes, which digest the extracellular matrix (ECM) scaffold surrounding human islets. This process remains highly variable and current isolation enzyme blends are ineffective at digesting pancreases from younger donors with low body mass indexes (BMI). However, age-related differences in pancreatic matrix digestion have not been studied in detail at the molecular level. To address this, we investigated ECM digestion in purified ECM proteins and in pancreatic tissue sections from younger (≤30 years; n = 5) and older (>55 years; n = 5) BMI matched donors, using Raman microspectroscopy (RMS). The Raman spectral profiles for purified collagens I, IV, VI and laminins were significantly altered following controlled enzyme treatment. Pancreatic cryosections were treated with Serva collagenase, NP, or the two enzymes combined, at clinically relevant concentrations. RMS demonstrated that the ECM at the islet-exocrine interface was differentially digested with respect to donor age. The action of collagenase was affected to a greater extent than NP. RMS is a powerful, marker-independent technology for characterising the human pancreatic ECM and demonstrating differences between donor types. Ongoing detailed studies using RMS will assist the development of donor-specific enzyme blends, increasing the overall success of human islet isolation and benefiting many people with type 1 diabetes worldwide. STATEMENT OF SIGNIFICANCE: Pancreatic islet transplantation is a minimally invasive treatment, which can reverse Type 1 Diabetes Mellitus (T1DM) in selected patients. Islets of Langerhans are extracted (isolated) from the exocrine tissue of human donor pancreases using neutral protease (NP) and collagenase-based enzymes, which digest the extracellular matrix (ECM) scaffold surrounding human islets. This process remains highly variable and current enzymes are ineffective at digesting pancreases from younger donors. Using Raman microspectroscopy we demonstrate that donor age affects the enzymatic digestion of the pancreatic ECM at the molecular level. Collagenase activity is affected to a greater extent than NP. These findings will assist the development of donor-specific enzymes, thereby increasing the overall success of islet isolation and benefiting many people with T1DM worldwide.

Does Islet Size Really Influence Graft Function After Clinical Islet Transplantation?

BACKGROUND: It has been proposed that islet transplants comprised primarily of small rather than large islets may provide better graft function, due to their lower susceptibility to hypoxic damage. Our aim was to determine whether islet size correlated with in vivo graft function in islet transplant recipients with C peptide-negative type 1 diabetes when islets have undergone pretransplant islet culture. METHODS: Human pancreatic islets were isolated, cultured for 24 hours and infused by standardized protocols. Ninety-minute stimulated C-peptide concentrations were determined during a standard meal tolerance test 3 months posttransplant. The islet isolation index (IEq/islet number) was determined immediately after isolation and again before transplantation (after tissue culture). This was correlated with patient insulin requirement or stimulated C-peptide. RESULTS: Changes in insulin requirement did not significantly correlate with islet isolation index. Stimulated C-peptide correlated weakly with IEq at isolation (P = 0.40) and significantly with IEq at transplantation (P = 0.018). Stimulated C-peptide correlated with islet number at isolation (P = 0.013) and more strongly with the islet number at transplantation (P = 0.001). In contrast, the correlation of stimulated C-peptide and islet isolation index was weaker (P = 0.018), and this was poorer at transplantation (P = 0.034). Using linear regression, the strongest association with graft function was islet number (r = 0.722, P = 0.001). Islet size was not related to graft function after adjusting for islet volume or number. CONCLUSIONS: These data show no clear correlation between islet isolation index and graft function; both small and large islets are suitable for transplantation, provided the islets have survived a short culture period postisolation.

Development of a Simple In Vitro Assay to Assess Digestion of the Extracellular Matrix of the Human Pancreas by Collagenase Enzyme Blends.

Despite huge advances in the field of islet transplantation over the last two decades, current islet isolation methods remain suboptimal, with transplantable yields obtained in less than half of all pancreases processed worldwide. Successful islet isolation is dependent on the ability of collagenase-based enzyme blends to digest extracellular matrix components at the islet-exocrine interface. The limited availability of donor pancreases hinders the use of full-scale islet isolations to characterize pancreas digestion by different enzyme components or blends, or allow the influence of inter-pancreatic variability between donors to be explored. We have developed a method that allows multiple enzyme components to be tested on any one pancreas. Biopsies of 0.5 cm3 were taken from seven standard (age ≥45) and eight young (age ≤35) pancreases. Serial cryosections were treated with Serva collagenase, neutral protease (NP), or the two enzymes together at clinically relevant concentrations. Following digestion, insulin and either collagen IV or laminin-α5 were detected by immunofluorescent labeling. Protein loss at the islet-exocrine interface was semi-quantified morphometrically, with reference to a control section. Differential digestion of the two proteins based on the enzyme components used was seen, with protein digestion significantly influenced by donor age. Treatment with collagenase and NP alone was significantly more effective at digesting collagen IV in the standard donor group, as was the NP mediated digestion of laminin-α5. Collagenase alone was not capable of significantly digesting laminin-α5 in either donor group. Combining the two enzymes ameliorated the age-related differences in the digestion of both proteins. No significant differences in protein loss were detected by the method when analyzed by two independent operators, demonstrating the reproducibility of the assay. The development of this simple yet reproducible assay has implications for both enzyme batch testing and identifying inter-donor digestion variability, while utilizing small amounts of both enzyme and human tissue.

In Vitro Assessment of Human Islet Vulnerability to Instant Blood-Mediated Inflammatory Reaction (IBMIR) and Its Use to Demonstrate a Beneficial Effect of Tissue Culture.

Culture of human pancreatic islets is now routinely carried out prior to clinical islet allotransplantation, using conditions that have been developed empirically. One of the major causes of early islet destruction after transplantation is the process termed instant blood-mediated inflammatory reaction (IBMIR). The aim of this study was to develop in vitro methods to investigate IBMIR and apply them to the culture conditions used routinely in our human islet isolation laboratory. Freshly isolated or precultured (24 h, 48 h) human islets were incubated in either ABO-compatible allogeneic human blood or Hank's buffered salt solution (HBSS) for 1 h at 37°C. Tissue factor (TF) expression and leukocyte migration were assessed by light microscopy. TF was also quantified by ELISA. To assess ß-cell function, glucose-stimulated insulin secretion (GSIS) assay was carried out. The extent of islet ß-cell damage was quantified using a proinsulin assay. Islets cultured for 24 h had higher GSIS when compared to freshly isolated or 48-h precultured islets. Freshly isolated islets had significantly higher TF content than 24-h and 48-h precultured islets. Incubation of freshly isolated human islets in allogeneic human blood released 6.5-fold higher level of proinsulin in comparison to freshly isolated human islets in HBSS. The high level of proinsulin released was significantly attenuated when precultured islets (24 h or 48 h) were exposed to fresh blood. Histological examination of fresh islets in blood clot showed that some islets were fragmented, showing signs of extraislet insulin leakage and extensive neutrophil infiltration and necrosis. These features were markedly reduced when the islets were cultured for 24 h. These results suggest that our standard 24-h islet culture is markedly beneficial in attenuating IBMIR, as evidenced by increased GSIS, lower content of TF, decrease islet fragmentation, and proinsulin release.

Impact of saturated, polyunsaturated and monounsaturated fatty acid-rich micelles on lipoprotein synthesis and secretion in Caco-2 cells.

Meal fatty acids have been shown to modulate the size and composition of triacylglycerol (TAG)-rich lipoproteins influencing the magnitude and duration of the postprandial plasma TAG response. As a result there is considerable interest in the origin of these meal fatty-acid induced differences in particle composition. Caco-2 cells were incubated over 4 days with fatty acid mixtures resembling the composition of saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA)-rich meals fed in a previous postprandial study to determine their impact on lipoprotein synthesis and secretion. The MUFA- and PUFA-rich mixtures supported greater intracellular TAG, but not cholesterol accumulation compared with the SFA-rich mixture (P < 0.001). The MUFA-rich mixture promoted significantly greater TAG and cholesterol secretion than the other mixtures and significantly more apolipoprotein B-100 secretion than the PUFA-rich mixture (P < 0.05). Electron microscopy revealed the SFA-rich mixture had led to unfavourable effects on cellular morphology, compared with the unsaturated fatty acid-rich mixtures. Our findings suggest the MUFA-rich mixture, may support the formation of a greater number of TAG-rich lipoproteins, which is consistent with indirect observations from our human study. Our electron micrographs are suggestive that some endocytotic uptake of MUFA-rich taurocholate micelles may promote greater lipoprotein synthesis and secretion in Caco-2 cells.

Differences in cell morphology, lipid and apo B secretory capacity in caco-2 cells following long term treatment with saturated and monounsaturated fatty acids.

The suitability of the caco-2 cell line as a model for studying the long term impact of dietary fatty acids on intestinal lipid handling and chylomicron production was examined. Chronic supplementation of caco-2 cells with palmitic acid (PA) resulted in a lower triacylglycerol secretion than oleic acid (OA). This was coupled with a detrimental effect of PA, but not OA, on transepithelial electrical resistance (TER) measurements, suggesting a loss of structural integrity across the cell monolayer. Addition of OA reversed the adverse effects of PA and stearic acid on TER and increased the ability of cells to synthesise and accumulate lipid, but did not normalise the secretion of lipids by caco-2 cells. Increasing amounts of OA and decreasing amounts of PA in the incubation media markedly improved the ability of cells to synthesise apolipoprotein B and secrete lipids. Real time RT-PCR revealed a down regulation of genes involved in lipoprotein synthesis following PA than OA. Electron microscopy showed adverse effects of PA on cellular morphology consistent with immature enterocytes such as stunted microvilli and poor tight junction formation. In conclusion, previously reported differences in lipoprotein secretion by caco-2 cells supplemented with saturated fatty acids (SFA) and OA may partly reflect early cytotoxic effects of SFA on cellular integrity and function.

Apolipoprotein E enrichment of immuno-separated chylomicron and chylomicron remnants following saturated fatty acids.

AIM: We examined the effect of meal fatty acids on lipid and apolipoprotein concentrations of very low density lipoprotein (VLDL) and chylomicron/chylomicron remnants in lipid fractions with a Svedberg flotation rate (Sf) 60-400 and Sf 20-60. METHODS AND RESULTS: Six healthy middle-aged men received in random order mixed meals enriched with saturated (SFA), polyunsaturated (PUFA) or monounsaturated (MUFA) fatty acids on 3 occasions. VLDL and chylomicron/chylomicron remnants in the lipid fractions were separated by immunoaffinity chromatography against apo B-100. In the Sf 60-400 chylomicron/chylomicron remnants, triacylglycerol and cholesterol concentrations were significantly lower following PUFA compared with SFA and MUFA (P < or = 0.05). Apolipoprotein (apo) E responses were significantly higher after SFA in chylomicron/chylomicron remnants and VLDL compared with PUFA and MUFA (P < 0.007). However, apo B responses (particle number) were higher following MUFA than SFA (P = 0.039 for chylomicron/chylomicron remnants). Composition of the chylomicron/chylomicron remnants (expressed per particle) revealed differences in their triacylglycerol and apo E contents; in the Sf 60-400 fraction, SFA-rich chylomicron/chylomicron remnants contained significantly more triacylglycerol than MUFA (P = 0.028), more apo E than PUFA- and MUFA-rich particles (P < 0.05) and in the Sf 20-60 fraction, more apo E than MUFA (P = 0.009). CONCLUSION: There are specific differences in the composition of chylomicron/chylomicron remnants formed after saturated compared with unsaturated fatty acid-rich meals which could determine their metabolic fate in the circulation and subsequent atherogenicity.

Acute effects of meal fatty acids on postprandial NEFA, glucose and apo E response: implications for insulin sensitivity and lipoprotein regulation?

Our aim was to determine whether meal fatty acids influence insulin and glucose responses to mixed meals and whether these effects can be explained by variations in postprandial NEFA and Apo, which regulate the metabolism of triacylglycerol-rich lipoproteins (Apo C and E). A single-blind crossover study examined the effects of single meals enriched in saturated fatty acids SFA), n-6 PUFA and MUFA on plasma metabolite and insulin responses. The triacylglycerol response following the PUFA meal showed a lower net incremental area under the curve than following the SFA and MUFA meals (P<0.007). Compared with the SFA meal, the PUFA meal showed a lower net incremental area under the curve for the NEFA response from initial suppression to the end of the postprandial period (180-480 min; P<0.02), and both PUFA and MUFA showed a lower net incremental glucose response (P<0.02), although insulin concentrations were similar between meals. The pattern of the Apo E response was also different following the SFA meal (P<0.02). There was a significant association between the net incremental NEFA (180-480 min) and glucose response (rs=0.409, P=0.025), and in multiple regression analysis the NEFA response accounted for 24 % of the variation in glucose response. Meal SFA have adverse effects on the postprandial glucose response that may be due to greater elevations in NEFA arising from differences in the metabolism of SFA- v. PUFA- and MUFA-rich lipoproteins. Elevated Apo E responses to high-SFA meals may have important implications for the hepatic metabolism of triacylglycerol-rich lipoproteins.

Greater enrichment of triacylglycerol-rich lipoproteins with apolipoproteins E and C-III after meals rich in saturated fatty acids than after meals rich in unsaturated fatty acids.

BACKGROUND: Although there is considerable interest in the postprandial events involved in the absorption of dietary fats and the subsequent metabolism of diet-derived triacylglycerol-rich lipoproteins, little is known about the effects of meal fatty acids on the composition of these particles. OBJECTIVE: We examined the effect of meal fatty acids on the lipid and apolipoprotein contents of triacylglycerol-rich lipoproteins. DESIGN: Ten normolipidemic men received in random order a mixed meal containing 50 g of a mixture of palm oil and cocoa butter [rich in saturated fatty acids (SFAs)], safflower oil [n-6 polyunsaturated fatty acids (PUFAs)], or olive oil [monounsaturated fatty acids (MUFAs)] on 3 occasions. Fasting and postprandial apolipoproteins B-48, B-100, E, C-II, and C-III and lipids (triacylglycerol and cholesterol) were measured in plasma fractions with Svedberg flotation rates (S(f)) >400, S(f) 60-400, and S(f) 20-60. RESULTS: Calculation of the composition of the triacylglycerol-rich lipoproteins (expressed per mole of apolipoprotein B) showed notable differences in the lipid and apolipoprotein contents of the SFA-enriched particles in the S(f) > 400 and S(f) 60-400 fractions. After the SFA meal, triacylglycerol-rich lipoproteins in these fractions showed significantly greater amounts of triacylglycerol and of apolipoproteins C-II (S(f) 60-400 fraction only), C-III, and E than were found after the MUFA meal (P < 0.02) and more cholesterol, apolipoprotein C-III (S(f) > 400 fraction only), and apolipoprotein E than after the PUFA meal (P < 0.02). CONCLUSIONS: Differences in the composition of S(f) > 400 and S(f) 60-400 triacylglycerol-rich lipoproteins formed after saturated compared with unsaturated fatty acid-rich meals may explain differences in the metabolic handling of dietary fats.