The Effects of 6-Chromanol SUL-138 during Hypothermic Machine Perfusion on Porcine Deceased Donor Kidneys

Diminishing ischemia-reperfusion injury (IRI) by improving kidney preservation techniques offers great beneficial value for kidney transplant recipients. Mitochondria play an important role in the pathogenesis of IRI and are therefore interesting targets for pharmacological interventions. Hypothermic machine perfusion (HMP), as a preservation strategy, offers the possibility to provide mitochondrial–targeted therapies. This study focuses on the addition of a mitochondrial protective agent SUL—138 during HMP and assesses its effect on kidney function and injury during normothermic reperfusion. In this case, 30 min of warm ischemia was applied to porcine slaughterhouse kidneys before 24 h of non–oxygenated HMP with or without the addition of SUL—138. Functional assessment was performed by 4 h normothermic autologous blood reperfusion. No differences in renal function or perfusion parameters were found between both groups. ATP levels were lower after 30 min of warm ischemia in the SUL–138 group (n.s, p = 0.067) but restored significantly during 24 h of HMP in combination with SUL—138. Aspartate aminotransferase (ASAT) levels were significantly lower for the SUL—138 group. SUL—138 does not influence renal function in this model. Restoration of ATP levels during 24 h of HMP with the addition of SUL in combination with lower ASAT levels could be an indication of improved mitochondrial function

Inhibition of Ferroptosis Enables Safe Rewarming of HEK293 Cells following Cooling in University of Wisconsin Cold Storage Solution

The prolonged cooling of cells results in cell death, in which both apoptosis and ferroptosis have been implicated. Preservation solutions such as the University of Wisconsin Cold Storage Solution (UW) encompass approaches addressing both. The use of UW improves survival and thus extends preservation limits, yet it remains unclear how exactly organ preservation solutions exert their cold protection. Thus, we explored cooling effects on lipid peroxidation and adenosine triphosphate (ATP) levels and the actions of blockers of apoptosis and ferroptosis, and of compounds enhancing mitochondrial function. Cooling and rewarming experiments were performed in a cellular transplantation model using Human Embryonic Kidney (HEK) 293 cells. Cell viability was assessed by neutral red assay. Lipid peroxidation levels were measured by Western blot against 4-Hydroxy-Nonenal (4HNE) and the determination of Malondialdehyde (MDA). ATP was measured by luciferase assay. Cooling beyond 5 h in Dulbecco's Modified Eagle Medium (DMEM) induced complete cell death in HEK293, whereas cooling in UW preserved ~60% of the cells, with a gradual decline afterwards. Cooling-induced cell death was not precluded by inhibiting apoptosis. In contrast, the blocking of ferroptosis by Ferrostatin-1 or maintaining of mitochondrial function by the 6-chromanol SUL150 completely inhibited cell death both in DMEM- and UW-cooled cells. Cooling for 24 h in UW followed by rewarming for 15 min induced a ~50% increase in MDA, while concomitantly lowering ATP by &gt;90%. Treatment with SUL150 of cooled and rewarmed HEK293 effectively precluded the increase in MDA and preserved normal ATP in both DMEM- and UW-cooled cells. Likewise, treatment with Ferrostatin-1 blocked the MDA increase and preserved the ATP of rewarmed UW HEK293 cells. Cooling-induced HEK293 cell death from hypothermia and/or rewarming was caused by ferroptosis rather than apoptosis. UW slowed down ferroptosis during hypothermia, but lipid peroxidation and ATP depletion rapidly ensued upon rewarming, ultimately resulting in complete cell death. Treatment throughout UW cooling with small-molecule Ferrostatin-1 or the 6-chromanol SUL150 effectively prevented ferroptosis, maintained ATP, and limited lipid peroxidation in UW-cooled cells. Counteracting ferroptosis during cooling in UW-based preservation solutions may provide a simple method to improve graft survival following cold static cooling.</p

The hibernation-derived compound SUL-138 shifts the mitochondrial proteome towards fatty acid metabolism and prevents cognitive decline and amyloid plaque formation in an Alzheimer’s disease mouse model

Background: Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease worldwide and remains without effective cure. Increasing evidence is supporting the mitochondrial cascade hypothesis, proposing that loss of mitochondrial fitness and subsequent ROS and ATP imbalance are important contributors to AD pathophysiology. Methods: Here, we tested the effects of SUL-138, a small hibernation-derived molecule that supports mitochondrial bioenergetics via complex I/IV activation, on molecular, physiological, behavioral, and pathological outcomes in APP/PS1 and wildtype mice. Results: SUL-138 treatment rescued long-term potentiation and hippocampal memory impairments and decreased beta-amyloid plaque load in APP/PS1 mice. This was paralleled by a partial rescue of dysregulated protein expression in APP/PS1 mice as assessed by mass spectrometry-based proteomics. In-depth analysis of protein expression revealed a prominent effect of SUL-138 in APP/PS1 mice on mitochondrial protein expression. SUL-138 increased the levels of proteins involved in fatty acid metabolism in both wildtype and APP/PS1 mice. Additionally, in APP/PS1 mice only, SUL-138 increased the levels of proteins involved in glycolysis and amino acid metabolism pathways, indicating that SUL-138 rescues mitochondrial impairments that are typically observed in AD. Conclusion: Our study demonstrates a SUL-138-induced shift in metabolic input towards the electron transport chain in synaptic mitochondria, coinciding with increased synaptic plasticity and memory. In conclusion, targeting mitochondrial bioenergetics might provide a promising new way to treat cognitive impairments in AD and reduce disease progression

Incidence and Prediction of Unrelated Mortality After Successful Endoscopic Eradication Therapy for Barrett's Neoplasia

Background &amp; Aims: Follow-up (FU) strategies after endoscopic eradication therapy (EET) for Barrett's neoplasia do not consider the risk of mortality from causes other than esophageal adenocarcinoma (EAC). We aimed to evaluate this risk during long-term FU, and to assess whether the Charlson Comorbidity Index (CCI) can predict mortality. Methods: We included all patients with successful EET from the nationwide Barrett registry in the Netherlands. Data were merged with National Statistics for accurate mortality data. We evaluated annual mortality rates (AMRs, per 1000 person-years) and standardized mortality ratio for other-cause mortality. Performance of the CCI was evaluated by discrimination and calibration. Results: We included 1154 patients with a mean age of 64 years (±9). During median 59 months (p25–p75 37–91; total 6375 person-years), 154 patients (13%) died from other causes than EAC (AMR, 24.1; 95% CI, 20.5–28.2), most commonly non-EAC cancers (n = 58), cardiovascular (n = 31), or pulmonary diseases (n = 26). Four patients died from recurrent EAC (AMR, 0.5; 95% CI, 0.1–1.4). Compared with the general Dutch population, mortality was significantly increased for patients in the lowest 3 age quartiles (ie, age &lt;71 years). Validation of CCI in our population showed good discrimination (Concordance statistic, 0.78; 95% CI, 0.72–0.84) and fair calibration. Conclusion: The other-cause mortality risk after successful EET was more than 40 times higher (48; 95% CI, 15–99) than the risk of EAC-related mortality. Our findings reveal that younger post-EET patients exhibit a significantly reduced life expectancy when compared with the general population. Furthermore, they emphasize the strong predictive ability of CCI for long-term mortality after EET. This straightforward scoring system can inform decisions regarding personalized FU, including appropriate cessation timing.</p

Sex Differences in Neoplastic Progression in Barrett's Esophagus:A Multicenter Prospective Cohort Study

Recommendations in Barrett’s esophagus (BE) guidelines are mainly based on male patients. We aimed to evaluate sex differences in BE patients in (1) probability of and (2) time to neoplastic progression, and (3) differences in the stage distribution of neoplasia. We conducted a multicenter prospective cohort study including 868 BE patients. Cox regression modeling and accelerated failure time modeling were used to estimate the sex differences. Neoplastic progression was defined as highgrade dysplasia (HGD) and/or esophageal adenocarcinoma (EAC). Among the 639 (74%) males and 229 females that were included (median follow-up 7.1 years), 61 (7.0%) developed HGD/EAC. Neoplastic progression risk was estimated to be twice as high among males (HR 2.26, 95% CI 1.11–4.62) than females. The risk of HGD was found to be higher in males (HR 3.76, 95% CI 1.33–10.6). Time to HGD/EAC (AR 0.52, 95% CI 0.29–0.95) and HGD (AR 0.40, 95% CI 0.19–0.86) was shorter in males. Females had proportionally more EAC than HGD and tended to have higher stages of neoplasia at diagnosis. In conclusion, both the risk of and time to neoplastic progression were higher in males. However, females were proportionally more often diagnosed with (advanced) EAC. We should strive for improved neoplastic risk stratification per individual BE patient, incorporating sex disparities into new prediction models

The Effects of 6-Chromanol SUL-138 during Hypothermic Machine Perfusion on Porcine Deceased Donor Kidneys

Diminishing ischemia-reperfusion injury (IRI) by improving kidney preservation techniques offers great beneficial value for kidney transplant recipients. Mitochondria play an important role in the pathogenesis of IRI and are therefore interesting targets for pharmacological interventions. Hypothermic machine perfusion (HMP), as a preservation strategy, offers the possibility to provide mitochondrial–targeted therapies. This study focuses on the addition of a mitochondrial protective agent SUL—138 during HMP and assesses its effect on kidney function and injury during normothermic reperfusion. In this case, 30 min of warm ischemia was applied to porcine slaughterhouse kidneys before 24 h of non–oxygenated HMP with or without the addition of SUL—138. Functional assessment was performed by 4 h normothermic autologous blood reperfusion. No differences in renal function or perfusion parameters were found between both groups. ATP levels were lower after 30 min of warm ischemia in the SUL–138 group (n.s, p = 0.067) but restored significantly during 24 h of HMP in combination with SUL—138. Aspartate aminotransferase (ASAT) levels were significantly lower for the SUL—138 group. SUL—138 does not influence renal function in this model. Restoration of ATP levels during 24 h of HMP with the addition of SUL in combination with lower ASAT levels could be an indication of improved mitochondrial function

The 6-hydroxychromanol derivative SUL-109 ameliorates renal injury after deep hypothermia and rewarming in rats

Background. Mitochondrial dysfunction plays an important role in kidney damage in various pathologies, including acute and chronic kidney injury and diabetic nephropathy. In addition to the well-studied ischaemia/reperfusion (I/R) injury, hypothermia/rewarming (H/R) also inflicts acute kidney injury. Substituted 6-hydroxychromanols are a novel class of mitochondrial medicines that ameliorate mitochondrial oxidative stress and protect the mitochondrial network. To identify a novel 6-hydroxychromanol that protects mitochondrial structure and function in the kidney during H/R, we screened multiple compounds in vitro and subsequently assessed the efficacy of the 6-hydroxychromanol derivatives SUL-109 and SUL-121 in vivo to protect against kidney injury after H/R in rats. Methods. Human proximal tubule cell viability was assessed following exposure to H/R for 48/4 h in the presence of various 6-hydroxychromanols. Selected compounds (SUL-109, SUL-121) or vehicle were administered to ketamine-anaesthetized male Wistar rats (IV 135 mu g/kg/h) undergoing H/R at 15 degrees C for 3 h followed by rewarming and normothermia for 1 h. Metabolic parameters and body temperature were measured throughout. In addition, renal function, renal injury, histopathology and mitochondrial fitness were assessed. Results. H/R injury in vitro lowered cell viability by 94 +/- 61%, which was counteracted dose-dependently by multiple 6-hydroxy-chomanols derivatives. In vivo, H/R in rats showed kidney injury molecule 1 expression in the kidney and tubular dilation, accompanied by double-strand DNA breaks and protein nitrosylation. SUL-109 and SUL-121 ameliorated tubular kidney damage, preserved mitochondrial mass and maintained cortical adenosine 50-triphosphate (ATP) levels, although SUL-121 did not reduce protein nitrosylation. Conclusions. The substituted 6-hydroxychromanols SUL-109 and SUL-121 ameliorate kidney injury during in vivo H/R by preserving mitochondrial mass, function and ATP levels. In addition, both 6-hydroxychromanols limit DNA damage, but only SUL-109 also prevented protein nitrosylation in tubular cells. Therefore SUL-109 offers a promising therapeutic strategy to preserve kidney mitochondrial function

The 6-hydroxychromanol derivative SUL-109 ameliorates renal injury after deep hypothermia and rewarming in rats

Background. Mitochondrial dysfunction plays an important role in kidney damage in various pathologies, including acute and chronic kidney injury and diabetic nephropathy. In addition to the well-studied ischaemia/reperfusion (I/R) injury, hypothermia/rewarming (H/R) also inflicts acute kidney injury. Substituted 6-hydroxychromanols are a novel class of mitochondrial medicines that ameliorate mitochondrial oxidative stress and protect the mitochondrial network. To identify a novel 6-hydroxychromanol that protects mitochondrial structure and function in the kidney during H/R, we screened multiple compounds in vitro and subsequently assessed the efficacy of the 6-hydroxychromanol derivatives SUL-109 and SUL-121 in vivo to protect against kidney injury after H/R in rats. Methods. Human proximal tubule cell viability was assessed following exposure to H/R for 48/4 h in the presence of various 6-hydroxychromanols. Selected compounds (SUL-109, SUL-121) or vehicle were administered to ketamine-anaesthetized male Wistar rats (IV 135 mu g/kg/h) undergoing H/R at 15 degrees C for 3 h followed by rewarming and normothermia for 1 h. Metabolic parameters and body temperature were measured throughout. In addition, renal function, renal injury, histopathology and mitochondrial fitness were assessed. Results. H/R injury in vitro lowered cell viability by 94 +/- 61%, which was counteracted dose-dependently by multiple 6-hydroxy-chomanols derivatives. In vivo, H/R in rats showed kidney injury molecule 1 expression in the kidney and tubular dilation, accompanied by double-strand DNA breaks and protein nitrosylation. SUL-109 and SUL-121 ameliorated tubular kidney damage, preserved mitochondrial mass and maintained cortical adenosine 50-triphosphate (ATP) levels, although SUL-121 did not reduce protein nitrosylation. Conclusions. The substituted 6-hydroxychromanols SUL-109 and SUL-121 ameliorate kidney injury during in vivo H/R by preserving mitochondrial mass, function and ATP levels. In addition, both 6-hydroxychromanols limit DNA damage, but only SUL-109 also prevented protein nitrosylation in tubular cells. Therefore SUL-109 offers a promising therapeutic strategy to preserve kidney mitochondrial function

Additional file of: A digital intake tool to avert outpatient visits in a FIT-based colorectal cancer screening population: study protocol of a multicentre, prospective non-randomized trial - the DIT-trial

Abstract Background Currently all participants of the Dutch colorectal cancer (CRC) screening program with a positive faecal immunochemical test (FIT) are seen at the outpatient clinic to assess their health status, receive information on colonoscopy and CRC risk, and provide informed consent. However, for many patients this information could probably also safely be exchanged in an online setting, in order to reduce the burden for patients, healthcare system, and environment. In this study we will evaluate if a face-to-face pre-colonoscopy consultation can be replaced by a Digital Intake Tool (DIT) in a CRC screening population. Methods This is a prospective multicentre single-arm, non-randomized study with a non-inferiority design. The DIT will triage a total of 1000 participants and inform them about CRC risk, colonoscopy, sedation, and provide bowel preparation instructions. Participants identified as high-risk (i.e., red-triaged) will be contacted by phone or scheduled for an appointment at the outpatient clinic. The primary outcome measure will be adequate bowel preparation rate, defined as the proportion of participants with a Boston Bowel Preparation (BBPS) score ≥ 6. To compare our primary outcome, we will use colonoscopy data from 1000 FIT positive participants who visited the outpatient clinic for pre-colonoscopy consultation. Secondary outcomes will include participation rate, colonoscopy adherence rate, patient experience in terms of satisfaction and anxiety, knowledge transfer, number of outpatient visits that can be averted by the DIT, and cost-effectiveness of the tool. Ethical approval was obtained from the Medical Ethical Committee of the Erasmus Medical Center (MEC-2021-0098). Discussion This study aims to assess if a face-to-face pre-colonoscopy consultation can be replaced by an eHealth assessment and education tool in a FIT-based CRC screening program. In case favourable results are established, the intervention evaluated in this study could significantly impact CRC screening programs, benefiting both patients and healthcare systems on a (inter)national scale. Additionally, it would enable more personalized care as the DIT can be easily customized and made feasible in other languages, thereby enhancing healthcare accessibility. Trial registration Dutch Trial Register: NL9315 , date of registration: March 8th, 2021

Additional file of: A digital intake tool to avert outpatient visits in a FIT-based colorectal cancer screening population: study protocol of a multicentre, prospective non-randomized trial - the DIT-trial

Abstract Background Currently all participants of the Dutch colorectal cancer (CRC) screening program with a positive faecal immunochemical test (FIT) are seen at the outpatient clinic to assess their health status, receive information on colonoscopy and CRC risk, and provide informed consent. However, for many patients this information could probably also safely be exchanged in an online setting, in order to reduce the burden for patients, healthcare system, and environment. In this study we will evaluate if a face-to-face pre-colonoscopy consultation can be replaced by a Digital Intake Tool (DIT) in a CRC screening population. Methods This is a prospective multicentre single-arm, non-randomized study with a non-inferiority design. The DIT will triage a total of 1000 participants and inform them about CRC risk, colonoscopy, sedation, and provide bowel preparation instructions. Participants identified as high-risk (i.e., red-triaged) will be contacted by phone or scheduled for an appointment at the outpatient clinic. The primary outcome measure will be adequate bowel preparation rate, defined as the proportion of participants with a Boston Bowel Preparation (BBPS) score ≥ 6. To compare our primary outcome, we will use colonoscopy data from 1000 FIT positive participants who visited the outpatient clinic for pre-colonoscopy consultation. Secondary outcomes will include participation rate, colonoscopy adherence rate, patient experience in terms of satisfaction and anxiety, knowledge transfer, number of outpatient visits that can be averted by the DIT, and cost-effectiveness of the tool. Ethical approval was obtained from the Medical Ethical Committee of the Erasmus Medical Center (MEC-2021-0098). Discussion This study aims to assess if a face-to-face pre-colonoscopy consultation can be replaced by an eHealth assessment and education tool in a FIT-based CRC screening program. In case favourable results are established, the intervention evaluated in this study could significantly impact CRC screening programs, benefiting both patients and healthcare systems on a (inter)national scale. Additionally, it would enable more personalized care as the DIT can be easily customized and made feasible in other languages, thereby enhancing healthcare accessibility. Trial registration Dutch Trial Register: NL9315 , date of registration: March 8th, 2021