Renal fibrosis is the final common pathway of chronic kidney disease progression and a critical histological predictor of renal function decline and allograft failure. Routine clinical monitoring with estimated glomerular filtration rate (eGFR) and albuminuria is insensitive to the development of fibrosis. Renal biopsy is invasive, which limits repeated assessment and suffers from sampling bias. Consequently, non-invasive imaging biomarkers that can accurately quantify fibrosis, monitor disease progression, and predict outcomes are highly desirable. Multiparametric magnetic resonance imaging (mpMRI) offers extensive characterization of renal structural and functional properties. Previous work has indicated that MRI measures are associated with fibrosis development and with declining renal function. However, there remains a sparsity of longitudinal data and comprehensive validation of MRI measures against histology and measured glomerular filtration rate (mGFR). Our ongoing longitudinal study aims to validate mpMRI against reference standard kidney biopsy in kidney transplant recipients (KTR) and to compare the time-dependent trajectories of imaging and functional markers across living kidney donors (LKD), KTR and healthy control (HC) cohorts to assess their prognostic value for mGFR decline. Participants: 32 living kidney donors (LKD), 32 KTR, and 32 healthy controls (HC). Inclusion criteria: LKD and KTR who have been approved for transplant. HC must show no evidence of renal disease and have normal blood pressure. Exclusion criteria: Contraindications to MRI or severe claustrophobia. Time points: Baseline investigations prior to transplant surgery, with follow-up assessments at 3-, 12-, and 24-months post-transplant. Data collection: mpMRI is performed at 3T. The MRI protocol includes structural T1-weighted and T2-weighted imaging, T1 mapping, T2 mapping, T2* mapping, DWI, pseudo-continuous ASL, non-contrast-enhanced angiography, and phase-contrast measurement of renal artery flow. Glomerular filtration rate will be measured by [99mTc]Tc-DTPA clearance. A baseline allograft biopsy is performed in all KTR during the transplantation surgery. Subsequent protocol biopsies are planned at 3, 12, and 24 months in KTR. Extent of fibrosis is quantified using quantitative stereology. Primary outcome: Longitudinal association between quantitative MRI measures and histologically determined renal fibrosis. Secondary outcomes: Longitudinal divergence of MRI and functional markers across cohorts; diagnostic performance for fibrosis; and predictive value for mGFR decline in KTR and LKD. Linear mixed models will be used to study longitudinal associations. Receiver operating characteristic curve analysis will assess diagnostic performance. Recruitment for the MPRENAL study commenced in November 2024. As of March 2026, enrolment is ongoing with 42 participants recruited. Full data analysis and results are projected for December 2029. Successful completion of this study is expected to provide robust histological validation of mpMRI and establish its utility as a non-invasive tool for monitoring renal health. ClinicalTrials.gov NCT06210555; https://clinicaltrials.gov/ct2/show/NCT06210555

Surgical resection remains the primary curative approach for malignant liver tumors and liver regeneration is essential for patient recovery following major hepatic resection. While its molecular and cellular mechanisms have been extensively studied, the in vivo metabolic dynamics underlying early regeneration remain incompletely characterized. Hyperpolarized [1-13C]pyruvate MRI (HP-MRI) offers a unique, noninvasive method to assess real-time metabolic fluxes in regenerating liver tissue. Twelve male Wistar rats were randomized to either 70% partial hepatectomy (PH; n = 6) or nonsurgical controls (n = 6). On postoperative day 1, all animals underwent HP-MRI and multiparametric proton MRI. Metabolic fluxes were quantified using area-under-the-curve ratios for lactate-to-pyruvate (L/P), alanine-to-pyruvate (A/P), and lactate-to-alanine (L/A). The PH group showed significantly higher L/P (0.267 [95% CI: 0.225-0.310] vs. 0.168 [95% CI: 0.135-0.200]; p < 0.001) and A/P (0.236 [95% CI: 0.153-0.319] vs. 0.150 [95% CI: 0.128-0.172]; p = 0.028) ratios compared to controls, indicating increased exchange of pyruvate to lactate and alanine. L/A ratios remained unchanged. These findings were supported by elevated biochemical markers of hepatic injury and changes in quantitative MRI parameters, including reduced ADC and IVIM flow fraction. HP-MRI revealed increased glycolytic and transaminase activity during early liver regeneration, consistent with the metabolic demands of hepatocyte proliferation. These results demonstrate the feasibility of HP-MRI for noninvasive metabolic assessment of liver regeneration in vivo and additionally provide insights into early regenerative metabolism. This suggests HP-MRI as a promising tool for assessing postoperative recovery in patients undergoing major hepatectomy.

AIM:Ketosis may represent a therapeutic target for age-related impairments in skeletal muscle function. This study investigated acute effects of ketosis on metabolic economy, mitochondrial function, and contractile parameters in skeletal muscle of young and older adults. METHODS:Twelve young (20-25 years) and twelve older (65-85 years) healthy men, matched by age-adjusted V̇O2max, participated in a randomized, crossover, double-blind intervention with ingestion of ketone monoester or placebo on separate study days. On both days, a low-dose, continuous glucose infusion blocked endogenous ketone production. Metabolic economy, oxidative capacity, muscle performance, intramuscular pH, and relative decline in peak power were assessed in the tibialis anterior through phosphorous MR spectroscopy (31P-MRS) and dynamometer recordings. Mitochondrial function of the quadriceps femoris muscle was assessed by high-resolution respirometry. RESULTS:Ketosis had no effect on metabolic economy in either young or older participants. The older group showed lower metabolic economy compared to the young group. In older participants, ketones increased ATP production and time-torque derived work capacity. Oxidative capacity was similar between groups and remained unaffected by ketones. In the older group, ketones improved peak power and increased both muscle relative decline in peak power and contraction-induced pH decline. Complex I + II respiration was lower in older compared to young participants, with no effect of ketones. CONCLUSION:Ketosis enhanced skeletal muscle work capacity and ATP production in older but not young adults, suggesting an age-specific effect of ketone bodies on muscle function that operates independently of changes in metabolic economy and mitochondrial function. These findings support ketosis as a promising ergogenic therapy for older adults. TRIAL REGISTRATION:The study was pre-registered at clinicaltrials.gov (NCT05732909).

OBJECTIVES:Medical disease-modifying treatments are lacking in Parkinson's disease (PD). Physical exercise is potentially an inexpensive and easily accessible disease-modifying therapy, but this remains to be studied using recent promising magnetic resonance imaging (MRI) markers of disease progression. The objective was to determine whether 24 weeks of moderate to high-intensity progressive aerobic exercise affects brain MRI measures in people with PD (pwPD). METHODS:A 24-week randomized controlled multicenter trial (with a 24-week follow-up) was conducted, including an exercise group (supervised aerobic exercise followed by self-guided physical activity) and a control group (habitual lifestyle). Patients older than 40 years with mild to moderate impairments (Hoehn & Yahr score ≤3) were randomized (1:1). The primary outcome was R2* (effective transverse relaxation rate) after 24 weeks, which was analyzed using the intention-to-treat principle. Additional outcomes included free water and neuromelanin levels in the substantia nigra, cardiorespiratory fitness, the Movement Disorder Society-sponsored Revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS), and levodopa equivalent daily dose (LEDD). RESULTS:Seventy participants were randomized to exercise (n = 36) or control (n = 34). R2* did not change over the intervention period (between-group difference: -1.14 [-5.14; 2.87], mean [95%CI]). Similarly, no significant effects were seen in cardiorespiratory fitness (+1.64 mL O2/min/kg [-0.23; 3.51]) and MDS-UPDRS III (-0.7 [-5.3; 4.0]), whereas LEDD increased less following exercise (-78.4 [-154.6; -2.1]). CONCLUSION:These findings do not support a neuroprotective effect of progressive aerobic exercise on R2* in pwPD, whereas the intervention appears to benefit the efficacy of levodopa. CLINICAL TRIAL REGISTRATION:Clinicaltrials.gov identifier: NCT04379778.

BACKGROUND:The aim of this study was to compare a normal saline bolus versus epinephrine during resuscitation on mortality and brain injury assessed by magnetic resonance spectroscopy (MRS) in newborn piglets. METHODS:Thirty-two newborn piglets were subjected to hypoxic cardiac arrest and randomized to resuscitation with epinephrine (0.01 mg/kg, n = 16) or saline bolus (0.9%, 10 mL/kg, n = 16). A sham group received no intravenous treatment (n = 8). Brain MRS and magnetic resonance imaging (MRI) were performed 18 h after resuscitation. The primary outcome was a composite of death or severe brain damage determined by MRS. Secondary outcomes were mortality, time to return of spontaneous circulation (ROSC), and MRI/MRS measures of brain injury. RESULTS:There was no difference between piglets resuscitated with saline bolus vs. epinephrine in the primary outcome (RR: 0.94, 95% CI: 0.56, 1.58). The two groups were also similar with regards to mortality, time to ROSC, and MRS/MRI-outcomes. Sham piglets had a higher mortality (RR: 1.50, 95% CI: 0.88, 2.55) than intravenous treatment groups, although not statistically significant. CONCLUSION:Saline bolus during resuscitation was as effective as epinephrine in preventing death and brain injury, as determined by MRS. Saline bolus may be a relevant alternative to epinephrine during neonatal resuscitation. IMPACT:Saline bolus is as effective as epinephrine in achieving return of spontaneous circulation in newborn piglets with hypoxic cardiac arrest. Saline bolus and epinephrine result in similar brain outcomes measured by magnetic resonance spectroscopy at 18 h. Saline bolus and epinephrine achieve similar time to return of spontaneous circulation and 18-h survival. This study adds to the limited evidence regarding the effect of saline volume expansion during neonatal resuscitation and underlines the need for clinical trials.

PURPOSE:To investigate changes in cerebral perfusion and cerebral oedema following cardiac arrest over a 24-h period. METHOD:Sixteen pigs were randomised to two groups: cardiac arrest group (n = 10) and sham group (n = 6). The cardiac arrest group was subjected to myocardial infarction and 9 min of untreated cardiac arrest. Cerebral blood flow and oedema were evaluated by repeated magnetic resonance imaging (MRI) at 3, 6, 12, and 24 h after achieving return of spontaneous circulation (ROSC). Sham pigs underwent MRI scans at corresponding time points. RESULTS:Global cerebral blood flow was lower in the cardiac arrest group with a mean group difference of 14.1 mL 100 g-1 min-1 (95% CI: 1.1-27.1; p = 0.028) at 6 h and 15.1 mL 100 g-1 min-1 (95% CI: 1.9-28.3; p = 0.018) at 12 h. Indications of cytotoxic oedema were present at 6 h in the form of lower apparent diffusion coefficient in the cardiac arrest group in the left cortex with a mean difference of 57.8·10-6 mm2/s (95% CI: 12.8-102.8; p = 0.006) and in the right cortex with a mean difference of 64.4 10-6 mm2/s (95% CI: 21.3-107.5; p = 0.001). Neuronal damage was evident by higher neuron specific enolase at 24 h in the cardiac arrest group with a mean difference of -1.14 μg/L (95% CI: -1.77 to -0.50; p < 0.001). CONCLUSION:We have demonstrated time-dependent cerebral hypoperfusion and region-specific cytotoxic oedema. Our results suggest that cerebral perfusion and cerebral oedema are potential targets of neuroprotection and their development can be evaluated by MRI.

Background:Multiparametric MRI (mpMRI) offers non-invasive characterization of renal microstructure and function, but its clinical translation is hindered by the lack of standardized post-processing. Manual segmentation is widely used but inherently observer-dependent. This study aimed to quantify the intra- and interobserver variability in manual segmentation of a comprehensive renal mpMRI protocol in a diverse cohort of patients with biopsy-confirmed chronic kidney disease (CKD). Methods:Seventy-two patients scheduled for diagnostic kidney biopsy were prospectively enrolled. Participants underwent mpMRI on a 1.5-T system prior to biopsy, including kidney volume assessment, T1 mapping, T2* [blood oxygen level-dependent (BOLD)], diffusion-weighted imaging [apparent diffusion coefficient (ADC)], arterial spin labeling (ASL), phase-contrast renal artery flow, and T1-rho mapping. Manual segmentation of the renal cortex and medulla was performed on three representative coronal slices. Two trained independent observers (one nephrologist, one radiologist) analyzed the cohort to assess interobserver variability. One observer repeated the full analysis after a six-month washout period to assess intraobserver variability. Agreement was evaluated using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Results:Complete datasets were available for 64 patients (mean estimated glomerular filtration rate 44 mL/min/1.73 m2; range, 3-132 mL/min/1.73 m2). Intra- and interobserver ICCs indicated good-to-excellent agreement for T1, T2*, and ADC in both cortical and medullary compartments (ICC range, 0.84-0.99). ASL showed excellent intraobserver reliability (ICC =0.94), but interobserver agreement was only good (ICC =0.78). Renal artery flow measurements also demonstrated good intra- and interobserver agreement (ICC =0.82 for both). T1-rho showed moderate-to-good intraobserver agreement (ICC range, 0.73-0.81) but was limited by image quality. Conclusions:Manual segmentation of renal cortex and medulla yields highly reproducible measurements for T1, T2*, ADC, renal artery flow and ASL in a mixed CKD population, supporting their validity for clinical research. However, the proportional bias in the Bland-Altmann plots for ASL and renal artery flow highlights the necessity for rigorous standardization of vessel selection and potential automation to ensure reliability across different readers.

Purpose To assess the feasibility of hyperpolarized [1-13C]pyruvate MRI (HP-MRI) as an adjunct to standard CT/MRI-based Liver Imaging Reporting and Data System (LI-RADS) categorization for noninvasive metabolic characterization of hepatocellular carcinoma (HCC). Materials and Methods This prospective, exploratory, single-center study included participants with liver lesions and control participants who underwent HP-MRI between June 2023 and June 2025. Lesions identified on CT and/or MRI scans were categorized according to LI-RADS. HP-MRI metabolic readout included ratios from dynamic 13C imaging, such as the lactate-to-pyruvate (L/P) ratio, alanine-to-pyruvate (A/P) ratio, alanine-to-lactate (A/L) ratio, and corresponding tumor-to-background ratios (TBRs). Established HCCs were compared with indeterminate lesions that subsequently progressed to HCC using unpaired t tests and Hedges g. Results Fourteen participants were included (median age, 64 years; IQR, 53-70 years]; 14 [100%] male): 10 participants with lesions on CT/MRI scans and four control participants. A/P and A/L ratios were lower in indeterminate lesions that progressed (n = 4) than established HCCs (n = 5), both in absolute measures and indexed to TBRs (P < .05), whereas there was no evidence of differences in the L/P ratio. In contrast, L/P TBR was higher in indeterminate lesions that progressed than in established HCCs (P = .03). Alanine-indexed TBRs showed large effect sizes, with Hedges g ranging from 2.01 (95% CI: 0.33, 3.70) to 3.02 (95% CI: 0.97, 5.08). One LI-RADS category 3 (LR-3) lesion under surveillance showed no early progression, and progression could not be confirmed for an LR-4 lesion. Conclusion Adjunctive HP-MRI provided complementary lesion-level metabolic information beyond standard CT and/or MRI, and a reduced A/L ratio emerged as a candidate marker of malignant progression. Keywords: Liver, Oncology, Cirrhosis, Hepatocellular Carcinoma Supplemental material is available for this article. Clinical Trials Information System hosted by the European Medicines Agency (EU-CTIS 2024-512490-27-00) © RSNA, 2026.

Aortic annuloplasty (AA) is an innovative surgical technique for aortic root (AR) enlargement. It is performed by implanting sutures, bands, or rings, either externally or internally the AR, hereby reducing its diameter. This study evaluates the impact of AA approaches on AR hemodynamic by employing a porcine-specific workflow combining in vivo magnetic resonance imaging (MRI), in vitro experiments and in silico fluid-structure interaction (FSI) simulations investigating external single ring AA. CAD models of native and post-annuloplasty ARs were segmented from in vivo porcine MRI data and served as the basis for fabricating 3D-printed resin phantoms and implementing computational digital twins. The former were tested on a pulsatile flow-loop, whereas the latter were integrated in FSI simulations, with time-dependent boundary conditions based on the resultant experimental pressure waveforms. Additionally, a proof-of-concept validation of the in silico model against in vivo data is proposed. Computational results of the two cases were compared in terms of fluid velocity, vorticity, helicity, and wall shear stresses, providing a step towards understanding the complex interactions between the AR and blood flow dynamics. Results suggested that the presence of the ring increased the systolic jet flow and post-valve velocities (three-fold increase), reduced the backward, vortical flow during diastole (∼ 9% decrease), and induced modifications in bulk flow and wall shear stresses distribution. Furthermore, the development of an animal-specific digital twin of a post-AA AR represents a significant advancement in the field, providing a valuable tool for future research and for clinical applications to aid AA decision-making process.

Partial hepatectomy (PH) is the primary treatment for liver malignancies, leveraging the liver’s regenerative capacity and metabolic potential. Transient hepatic steatosis is a common occurrence following PH. This study aimed to evaluate the utility of MRI-derived proton density fat fraction (MRI-PDFF) for assessing hepatic lipid content in the regenerating rat liver by correlating it with stereological lipid quantification, used as a histological reference standard. Rats were randomly assigned to 70%PH (n = 6) or no surgery (n = 6) and evaluated at postoperative day 1. Regeneration ratio was calculated, and lipid-specific biochemistry was measured. Hepatocyte proliferation and volume, as well as lipid volume per hepatocyte, were estimated using stereological analyses. Proton density fat fraction was quantified using MRI. Compared to controls, the PH group showed increased regeneration ratio, hepatocyte volume, and cell proliferation. Hepatic lipid accumulation was elevated, as demonstrated by both stereology and MRI. A strong positive correlation was observed between stereological lipid volume per hepatocyte and MRI-PDFF. High-density lipoprotein cholesterol levels were reduced in the PH group. This study demonstrates that stereological analysis and MRI-PDFF are complementary and reliable methods for quantifying hepatic steatosis in the regenerating rat liver. Their strong correlation supports MRI-PDFF for non-invasive, longitudinal monitoring.

Partial hepatectomy (PH) is the primary treatment for liver malignancies, leveraging the liver’s regenerative capacity and metabolic potential. Transient hepatic steatosis is a common occurrence following PH. This study aimed to evaluate the utility of MRI-derived proton density fat fraction (MRI-PDFF) for assessing hepatic lipid content in the regenerating rat liver by correlating it with stereological lipid quantification, used as a histological reference standard. Rats were randomly assigned to 70

To assess multi-site and multi-vendor accuracy, and intra- and inter-scanner variability of T1 and T2 measurements using the ISMRM/NIST System MRI phantom at room temperature. T1 and T2 measurements were acquired using standardized NIST protocols on 13 scanners (1.5 T and 3 T) from 3 vendors at 7 sites and compared with reference values at room temperature. Pearson’s correlation (r) and accuracy error were used for comparison with reference values, while inter-scanner agreement was assessed using the coefficient of variation (CV

To validate multi-site and multi-vendor ADC measurements using the QIBA/NIST diffusion MRI phantom at room temperature. ADC measurements were performed on 12 scanners (evenly split between 1.5 and 3 T) from three vendors at five sites and compared with reference values at room temperature. We adopted Pearson’s correlation (r) and accuracy error for comparison with reference values; within scanner coefficient of variation (CVintra α =0.05) to compare accuracy, repeatability and precision across field strengths, vendors, and scanners. Temperature adjusted ADCs were well correlated with NIST reference values (r ≥ 0.997 for 1.5 T, r ≥ 0.996 for 3 T). Median accuracy error was lower than 5 × 10−3 mm2/s), accuracy error was < 10

PURPOSE:Reliable information about renal blood supply is important to understand kidney physiology and diseases. Arterial spin labeling MR (ASL-MR) imaging and [15O]H2O positron emission tomography (PET) can noninvasively measure tissue perfusion but have never been directly compared. Using a hybrid PET/MR scanner, we performed simultaneous cortex perfusion measurements to assess repeatability and reproducibility of both modalities and establish their mutual correlation. METHODS:Ten healthy subjects (mean 25 years, 5 males) with normal glomerular filtration rate were examined twice, 16 days (range 12-23) apart. Repeatability was assessed on Day 1 with two successive examinations. A single scan on Day 2 was used to assess reproducibility. RESULTS:Single-kidney perfusion varied between individuals from 150 to 422 mL/min/100 mL for ASL-MR and from 184 to 470 mL/min/100 mL for PET. Repeatability and reproducibility were comparable between ASL-MR and PET. Bias was generally low (-13 to 5 mL/min/100 mL), but 95% limits of agreement (LoAs) were wide, ranging from 69 to 88 mL/min/100 mL. Overall, correlations between ASL-MR and PET perfusion values were weak, and in a linear mixed-effects model, bias was 18 and LoA 136 mL/min/100 mL. Agreement between ASL-MR and PET was acceptable at perfusion values between approximately 250 and 350 mL/min/100 mL. At lower perfusion, PET exceeded ASL-MR, whereas the opposite was observed at higher perfusion. CONCLUSION:ASL-MR and [15O]H2O PET renal cortical perfusion show comparable repeatability and reproducibility. Although perfusion obtained with the two modalities overall correlate weakly, there is an acceptable agreement in the mid-physiological range.

Although pig-to-baboon cardiac xenotransplantation has become increasingly successful, challenges remain in its clinical translation, particularly in addressing xenograft overgrowth. While several causes can be managed through genetic modifications and hemodynamic control, growth persists. Research on myocardial architecture and interspecies variation is limited. This study employs diffusion tensor imaging to probe the orientation of cardiomyocytes and their aggregations and aims to investigate whether these parameters may act as intrinsic factors, contributing to xenograft overgrowth in a setting of extrinsic hemodynamic mismatch. Five pig and five baboon ex-vivo hearts were compared by cardiac diffusion tensor magnetic resonance imaging. Myocardial architecture was assessed by quantifying helical, intrusion and E3-angles in left ventricle, septum and right ventricle. Notable differences were found in E3-angles of the left ventricle. The E3 angle was closer to 0° throughout the baboon myocardium. The epicardial E3-angle differed by -9°, midwall by -17.1°, and endocardial by -23.7° The myocardial architecture observed in baboon hearts may support a greater contractional deformation, potentially reflecting an enhanced contractile potential as compared to the porcine heart. Further ex- and in-vivo investigation of both pre- and post-transplantation animals is warranted to assess the exact functional implications of these myocardial architecture differences.

BACKGROUND:Aortic annuloplasty, involving the implantation of an external ring around the aortic root to reduce annular dimensions, is a promising treatment for aortic valve insufficiency. However, its hemodynamic effects remain underexplored due to the absence of computational models validated by experimental and clinical data. METHODS:This study introduces a computational fluid-structure interaction (FSI) model of supra valvular aortic annuloplasty using 4D-flow magnetic resonance imaging (MRI). Native and post-annuloplasty conditions of idealized aortic root phantoms, including the aortic valve, were CAD-modelled and 3D-printed with elastic resin. These phantoms were tested in a mock circulatory flow-loop providing normal pulsatile physiologic conditions using a glycerol-water mixture to simulate blood viscosity. Flow and pressure data collected from sensors were used as boundary conditions for FSI simulations. Experimental velocity fields from 4D-flow MRI were compared to computational results to assess model accuracy. RESULTS:MRI scans of the annuloplasty model showed an increased peak systolic velocity (up to 145.4 cm/s) and localized flow alterations, corresponding to a higher pressure gradient across the valve. During regurgitation, the annuloplasty model showed broader velocity distributions compared to the native condition. The FSI simulations closely matched 4D-flow MRI data, with strong correlation coefficients (r > 0.93) and minimal Bland-Altman differences, particularly during systolic phases. CONCLUSIONS:This study establishes an integrative methodology combining in-vitro, in-silico, and clinical imaging techniques to evaluate aortic annuloplasty hemodynamics. The in-vitro validated digital twin framework offers a pathway for patient-specific modelling, enabling prediction of surgical outcomes and optimization of aortic valve repair strategies.

The aim was to establish combined H215O PET/MRI during ex vivo normothermic machine perfusion (NMP) of isolated porcine kidneys. We examined whether changes in renal arterial blood flow (RABF) are accompanied by changes of a similar magnitude in renal blood perfusion (RBP) as well as the relation between RBP and renal parenchymal oxygenation (RPO). Methods: Pig kidneys (n = 7) were connected to a NMP circuit. PET/MRI was performed at two different pump flow levels: a blood-oxygenation-level-dependent (BOLD) MRI sequence performed simultaneously with a H215O PET sequence for determination of RBP. Results: RBP was measured using H215O PET in all kidneys (flow 1: 0.42–0.76 mL/min/g, flow 2: 0.7–1.6 mL/min/g). We found a linear correlation between changes in delivered blood flow from the perfusion pump and changes in the measured RBP using PET imaging (r2 = 0.87). Conclusion: Our study demonstrated the feasibility of combined H215O PET/MRI during NMP of isolated porcine kidneys with tissue oxygenation being stable over time. The introduction of H215O PET/MRI in nephrological research could be highly relevant for future pre-transplant kidney evaluation and as a tool for studying renal physiology in healthy and diseased kidneys.

Glucagon-like peptide-1 receptor agonists (GLP-1ras) and sodium–glucose cotransporter 2 inhibitors (SGLT2is) have shown kidney-protective effects. Improved kidney oxygenation and haemodynamic changes are suggested mechanisms; however, human data are scarce. We therefore investigated whether semaglutide (GLP-1ra), empagliflozin (SGLT2i) or their combination improve kidney oxygenation and perfusion. The trial was undertaken at Aarhus University Hospital, Denmark. A total of 120 people with type 2 diabetes (HbA1c ≥48 mmol/mol [6.5

Background: Coffee consumption is inversely associated with type 2 diabetes. Cafestol, a bioactive compound in coffee, has demonstrated glucose-lowering and insulin-secretory properties in cell and animal studies. The acute effects of cafestol on glucose metabolism in humans have only been briefly investigated, and longer-term effects have not been explored. This study aimed to assess the effects of purified cafestol on insulin sensitivity and other metabolic parameters in healthy individuals with increased waist circumference at risk of developing type 2 diabetes. Methods: A 12-week randomized, placebo-controlled, parallel trial was conducted with 40 participants. Insulin suppression tests, mixed meal tests, and MRI scans were performed before and after the intervention. Results: Administering 6 mg of cafestol twice daily did not alter insulin sensitivity or glucose tolerance but led to significant reductions in body weight (2%), visceral fat volume (5%), and gamma-glutamyl transferase levels (15%) compared to the placebo. Conclusions: Cafestol may hold promise for weight and visceral fat reduction. Cafestol did not improve insulin sensitivity or glucose tolerance in this study but might still contribute to the observed inverse association between coffee consumption and type 2 diabetes. Future research should explore higher dosages and longer treatment durations, particularly in individuals with impaired glucose metabolism and type 2 diabetes.