Citations

Mayo Clinic

Clear

2931 citation(s) found for "Ryan, M".

P-1228. Posaconazole Oral Suspension vs. Crushed Delayed-Release Tablets: Probability of Pharmacokinetic Target Attainment with Enteral Tube Administration
Bhattarai, Nirjan , O’Connell, Casey, Robinson, John, Cole, Kristin, Johnson, Tanner M , Stevens, Ryan W W, Wieruszewski, Patrick M. , Ilges, Dan , Stevens, Ryan W.

Open Forum Infectious Diseases | January 12, 2026 | Volume: 13 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofaf695.1420 Get It

Abstract Background Posaconazole immediate release (IR) suspension is the standard product for enteral feeding tube (EFT) administration but has erratic pharmacokinetic behavior and results in sub satisfactory concentrations. Limited evidence suggests that the posaconazole oral delayed-release (DR) tablets may be crushed. Methods This was a retrospective cohort study of hospitalized adults who received EFT administration of posaconazole IR suspension or crushed DR tablets between 2018 and 2024. Patients were eligible if they had at least one serum concentration drawn ≥5 days after posaconazole initiation. The primary outcome was the attainment of therapeutic (≥700ng/mL for prophylaxis, ≥1,000ng/mL for treatment) serum concentration within 30 days. Secondary outcomes included time to therapeutic serum concentration, adverse drug effects, and frequency of clogged EFT. Multivariable cox proportional hazards regression was used to assess the relationship between posaconazole formulation and attainment of therapeutic concentrations while adjusting for confounding variables. Results Of the included patients, 100 received DR tablets and 48 received IR suspension. There were no significant differences in baseline characteristics or severity of illness. Among DR tablet and IR suspension recipients, 59% and 23% achieved therapeutic concentrations, respectively (p < 0.001). After adjusting for age, sex, BMI, drug interactions, posaconazole indication, malabsorptive gastrointestinal conditions, IR suspension was significantly less likely than crushed DR tablets to achieve therapeutic posaconazole concentrations within 30-days (HR 0.37, 95% CI 0.20-0.71; p < 0.003). The crushed DR tablet group required less total daily posaconazole to achieve therapeutic concentrations (400 vs 600 mg/day, p = 0.003). Clogged EFTs were more frequent in the crushed DR tablet group (27% vs 10%, p = 0.022), while no differences were observed in the occurrence of hepatotoxicity or hypokalemia. Conclusion Administration of crushed posaconazole DR tablets via EFT is more likely to attain therapeutic concentrations compared to IR suspension. The optimal technique for administering crushed DR tablets to prevent EFT complications warrants investigation. Disclosures Patrick M. Wieruszewski, PharmD, FCCM, Wolters Kluwer/UpToDate: Advisor/Consultant
P-68. Effect of hypoalbuminemia on blood culture clearance and outcomes in methicillin-susceptible Staphylococcus aureus bacteremia managed with antistaphylococcal penicillins or cefazolin
Stevens, Ryan W W, Baddour, L.M., Cole, Kristin, Kooda, Kirstin , Robinson, John, Stevens, Ryan W. , DeSimone, Daniel C. , Ilges, Dan

Open Forum Infectious Diseases | January 12, 2026 | Volume: 13 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofaf695.297 Get It

Abstract Background Methicillin-susceptible Staphylococcus aureus bacteremia (MS-SAB) is treated with antistaphylococcal penicillins (ASP) or cefazolin. Altered pharmacokinetics in the setting of hypoalbuminemia may reduce the likelihood of therapeutic success in patients receiving highly protein bound beta-lactams. ASPs and cefazolin are 94% and 80% protein bound, respectively. We assessed the impact of hypoalbuminemia (≤2.5 g/dL) on clinical outcomes in patients with MS-SAB treated with ASPs or cefazolin.Table 1:Unweighted and weighted analysis of full cohort by albumin statusTable 2:Weighted analysis of cefazolin and ASP cohorts by albumin status Methods This single center, retrospective study included adults (≥18 years) admitted with community-acquired MS-SAB between 1/1/2006 and 12/31/2019 who received ASPs or cefazolin and had a serum albumin obtained between the date of first culture positivity and 72 hours of definitive therapy. Exclusion criteria included receipt of ≥5 days of MSSA active empiric therapy prior to definitive, polymicrobial bacteremia, antibiotics for an indication other than MS-SAB, or central nervous system infection. The primary outcome was failure to clear blood cultures within 72 hours of definitive therapy initiation. Propensity score weighting was used to adjust for baseline differences between cohorts. Results 160 patients were included with 61 (38.1%) being hypoalbuminemic (Table 1). In the propensity score weighted analysis, the primary outcome occurred in 37% of patients with an albumin ≤2.5 g/dL vs. 10.2% with an albumin >2.5 g/dL (p< 0.001). This finding was consistent in both ASP and cefazolin subgroups (Table 2). Hospital length of stay was longer in hypoalbuminemic patients but did not represent a statistically significant difference in the weighted overall analysis (15.9 vs. 11.6 days, p=0.8). There was no difference in inpatient mortality in any of the cohorts analyzed. 90-day all-cause mortality was higher in hypoalbuminemic patients only in the cefazolin subgroup analysis (20.7% vs 4.9%, p=0.019). Conclusion The presence of hypoalbuminemia was associated with failure to clear blood cultures within 72 hours of definitive therapy initiation in patients with MS-SAB. While no significant difference in mortality was observed overall, the higher mortality in the cefazolin subgroup warrants further research on the impact of hypoalbuminemia on clinical outcomes in patients with MS-SAB. Disclosures Larry M. Baddour, MD, UpToDate, Inc.: Royalty payments (authorship duties).
P-4. The Clinical Characteristics and Outcomes of Combination Therapy on Methicillin-susceptible Staphylococcus aureus Bacteremia: A 5-Year Experience
Al-Shokri, Shaikha D., Saleh, Omar M Abu, Yetmar, Zachary, Stevens, Ryan W W, Al-Shokri, Shaikha D. , Kim, Myeongji , Saleh, Omar Abu , Ranganath, Nischal , Yetmar, Zachary A. , Stevens, Ryan W. , Chesdachai, Supavit

Open Forum Infectious Diseases | January 12, 2026 | Volume: 13 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofaf695.235 Get It

Abstract Background Despite effective therapy for methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia with anti-staphylococcal penicillins (ASP; e.g., oxacillin, nafcillin) or cefazolin, persistent bacteremia is associated with poorer clinical outcomes and increased complications. Emerging strategies, such as combination therapy with an ASP or cefazolin and ertapenem, have demonstrated the potential to accelerate microbiologic clearance in persistent MSSA bacteremia. However, despite its increasing utilization in clinical practice, data on the effectiveness of this combination regimen remains limited. We sought to describe the clinical characteristics and outcomes of patients with MSSA bacteremia receiving combination therapy. Methods We performed a single-center, retrospective study of adult patients with MSSA bacteremia who received ASP or cefazolin and ertapenem combination therapy from 2019-2023. Time to blood culture clearance, in-hospital mortality, and 90-day relapse were examined. Results A total of 57 patients were included: median age of 65 years [IQR 53-73] with 75.4% male. MSSA bacteremia complicated by infective endocarditis and cardiac implantable electronic device infection occurred in 35.1% and 12.3%, respectively. The median length-of-stay was 16 days [IQR 12-28], and 57.9% required ICU admission. Forty (70.2%) patients underwent source control interventions such as valve replacement, device extraction or surgical debridement. The median duration of bacteremia prior to combination therapy initiation was 4 days [IQR 3-6]. Blood culture clearance occurred in a median of 1 day. The median duration of combination therapy was 4 days [IQR 3-6]. In-hospital mortality was 15.8%. None of the patients surviving the hospitalization experienced relapsed bacteremia within 90 days. Conclusion This study supports growing evidence that combination therapy may offer benefits in managing persistent MSSA bacteremia, specifically with regards to time to blood culture clearance. Further investigation is warranted to determine optimal timing of combination therapy and if known benefits of combination therapy translate into superior clinical outcomes as compared to monotherapy. Disclosures All Authors: No reported disclosures
299. Consequences of Delaying Surgical Intervention in Patients with Native Joint Septic Arthritis
Matsuo, Takahiro, B, Khodadadi Ryan, Lahr, B., Saleh, Omar M Abu, Suh, Gina A, Lahr, Brian D. , Saleh, Omar Abu , Damronglerd, Pansachee , McHugh, Jack , Zein, Said El , Suh, Gina A. , Tande, Aaron J.

Open Forum Infectious Diseases | January 12, 2026 | Volume: 13 | Issue: Supplement_1 | Pages: No page available

10.1093/ofid/ofaf695.101 Get It

Abstract Background Native joint septic arthritis (NJSA) is a serious musculoskeletal infection requiring timely surgical intervention to prevent long-term morbidity. Although current guidelines recommend early surgical debridement, supporting data, particularly on long-term outcomes, remain scarce. Given this, we evaluated the association between surgical timing and 1-year clinical outcomes using the Desirability of Outcome Ranking (DOOR) framework, applied for the first time in NJSA.Table 1.Desirability of Outcome Ranking (DOOR) ordinal scaleTable 2.Baseline demographic, clinical characteristics, and treatment outcomes Methods We conducted a retrospective multicenter cohort study of adults (≥18 years) with NJSA who underwent surgery across Mayo Clinic campuses between 2012 and 2021. Clinical outcomes at one year were assessed using a 9-level DOOR scale, incorporating survival, treatment failure (relapse, reinfection, readmission, or significant surgical events), and joint recovery (full vs qualified) (Table 1). Time to surgery from hospital admission was analyzed both as a continuous variable and as categories: < 1, 1–2, or ≥3 days.Table 3.Associations between duration and outcomesFigure 1.Association Between Time to Surgery and DOOR Scores in Native Joint Septic Arthritis.A) Distribution of Modified DOOR Scores by Surgical Timing. B) Modeled Probability of DOOR Scores by Time to Surgery. Results Among 268 patients (median age 62 years, 61% male), 30% underwent surgery < 1 day from admission, 47% within 1–2 days, and 24% at ≥3 days. At 1 year, 57% achieved full recovery without unfavorable events (DOOR score 1), while treatment failure occurred in 34% (Table 2). In unadjusted analyses, longer surgical delay was significantly associated with higher DOOR scores (per IQR increase [from 0 to 2 days], OR: 1.5; 95% CI: 1.0–2.1; p = 0.026) and with increased 1-year mortality (HR: 1.7; 95% CI: 1.1–2.6; p = 0.019) and treatment failure (HR: 1.5; 95% CI: 1.1–2.0; p = 0.007). Similar results were obtained when delay was used as a categorical 3-level variable, with the highest risk observed in patients undergoing surgery after ≥3 days. After adjusting for age and Charlson index, only the association between surgical delay and treatment failure remained statistically significant (HR: 1.5; 95% CI, 1.1–2.0; p=0.016) (Table 3, Figure 1). Conclusion Delayed surgical intervention for management of NJSA was independently associated with higher risk of treatment failure at 1 year. These findings reinforce current guideline recommendations for timely operative management and further underscore the potential of the DOOR framework to capture clinically meaningful, multidimensional outcomes in NJSA. Disclosures All Authors: No reported disclosures
Oral rehydration solution for the management of fluid and electrolyte disturbances in patients with an ileostomy: A scoping review
Hoeg, Austin , Jaques, Jessica, Johnson, Remy, Kocher, Megan , Vaughn, Byron P. , Khoruts, Alexander , Jahansouz, Cyrus , Rd, Hurt, Teigen, Levi , Hoeg, Austin J , Hurt, Ryan T. , Teigen, Levi M , Weingarden, Alexa R.

Journal of Parenteral and Enteral Nutrition | January 9, 2026 | Volume: 50 | Issue: 3 | Pages: 339-351

10.1002/jpen.70050 | PMID 41508901 Get It

Abstract Ileostomy creation is common among patients with colorectal cancer, diverticulitis, and inflammatory bowel disease. Surgical removal or diversion of the colon can result in nutrition complications, most notably dehydration—a leading cause of hospital readmission—and increased risk of kidney injury. Existing studies on fluid and electrolyte management after ileostomy largely focus on short bowel syndrome or high‐output stomas, overlooking the physiological implications of ileostomy creation, even in patients with normal output. Given the absence of standardized oral rehydration protocols and limited interventional data, a scoping review was conducted to map the current evidence on oral rehydration solutions for postoperative fluid and electrolyte management in adults without short bowel syndrome or high‐output stoma. Comprehensive searches across five databases identified 5738 articles, of which 6 met inclusion criteria. Eligible studies examined adults with ileostomy for any standard indication in which oral rehydration solution use was a study objective. The included studies were methodologically heterogeneous, encompassing randomized controlled, crossover, double‐blinded comparator, retrospective cohort, and qualitative designs. Collectively, available evidence supports a pivotal role for oral rehydration solutions in both short‐term and long‐term management after ileostomy, improving hydration and reducing complications. This review highlights the need for standardized, evidence‐based oral rehydration regimens and underscores opportunities to reduce postoperative morbidity, kidney injury, and hospital readmissions while optimizing long‐term outcomes in this growing patient population.
Heterogeneous tau patterns in atypical AD are explained by connectivity‐associated tau progression
Bruin, Hannah de , Groot, Colin , (ADNI), Alzheimer's Disease Neuroimaging Initiative, Barthel, Henryk, Bischof, Gérard N. , Boon, Baayla D.C., Brendel, Matthias, Cash, David M, Day, Gregory S, Dickerson, Brad C., Dyck, Christopher H van, Flier, Wiesje M. van der, Fredericks, Carolyn , Fryer, Tim D. , Giessen, Elsmarieke van de, Gordon, Brian A., Radford, Jonathan Graff, Hansson, Oskar H., Höglinger, Günter U, Hönig, Merle C., Irwin, David J., Jones, P Simon, Josephs, Keith A., Katsumi, Yuta , Lee, Eddie B., Xiong, Chengjie , McGinnis, Scott M., Mecca, Adam P. , O'Brien, John T, O'Dell, Ryan S, Rabinovici, Gil D., Rahmouni, Nesrine, Rosa‐Neto, Pedro, Sabri, Osama, Schott, Jonathan M, Schroeter, Matthias L, Seeley, William W., Servaes, Stijn, Sintini, Irene , Smith, Ruben, Stevenson, Jenna , Strandberg, Olof, Therriault, Joseph, Tideman, Pontus , Touroutoglou, Alexandra , Trainer, Anne, Wekselman, Fattin, Weston, Philip SJ., Whitwell, Jennifer L., Yong, Keir X X, O’Brien, John T. , Rabinovici, Gil D. , Day, Gregory S. , O'Brien, John Tiernan , Day, Gregory S , Xiong, Chengjie , Rabinovici, Gil D , Groot, Colin , Initiative, Alzheimer's Disease Neuroimaging, Blazhenets, Ganna , Boellaard, Ronald , Boon, Baayla D.C. , Brendel, Matthias , Cash, David M. , Coath, William , Dickerson, Brad C., Doering, Elena , Drzezga, Alexander E. , Dyck, Christopher H. van , Eimeren, Thilo van , Flier, Wiesje M. van der , Giessen, Elsmarieke van de , Gordon, Brian A. , Grinberg, Lea T. , Hansson, Oskar , Hobbs, Diana A. , Höglinger, Günter U. , Irwin, David J. , Jones, Peter Simon , Josephs, Keith A. , Joie, Renaud La , Lee, Eddie B, Malpetti, Maura , Mohanty, Rosaleena , Nasrallah, Ilya M. , O’Dell, Ryan S. , Palleis, Carla , Perneczky, Robert , Phillips, Jeffrey S , Putcha, Deepti , Rahmouni, Nesrine , Rosa-Neto, Pedro , Rowe, James B. , Rullmann, Michael , Saur, Dorothee , Schildan, Andreas , Schott, Jonathan M. , Schroeter, Matthias L , Seeley, William W. , Servaes, Stijn , Spina, Salvatore , Stomrud, Erik , Therriault, Joseph , Visser, Denise , Weston, Philip S.J. , Whitwell, Jennifer L. , Wolk, David A. , Yong, Keir , Pijnenburg, Yolande A.L. , Franzmeier, Nicolai , Ossenkoppele, Rik

Alzheimer's & Dementia | January 7, 2026 | Volume: 21 | Issue: S2 | Pages: No page available

10.1002/alz70856_104871 Get It

Abstract Background The link between regional tau load and clinical manifestation of Alzheimer's disease (AD) highlights the importance of characterizing spatial tau distribution. In typical (memory‐predominant) AD, the spatial progression of tau pathology mirrors the functional connections from temporal lobe epicenters. However, atypical (non‐amnestic‐predominant) AD variants with heterogeneous tau patterns provide a key opportunity to assess the universality of connectivity as a scaffold for tau progression. Method We included tau‐PET data from 320 subjects with atypical AD, characterized by highly heterogeneous tau patterns ( n = 139 posterior cortical atrophy/PCA‐AD; n = 103 logopenic variant primary progressive aphasia/lvPPA‐AD; n = 35 behavioural variant AD/bvAD; n = 43 corticobasal syndrome/CBS‐AD) from 14 sites, with a subset of patients ( n = 78) having longitudinal tau‐PET data. As an independent sample, we further included regional post‐mortem tau stainings from 93 atypical AD patients from two sites ( n = 19 PCA‐AD, n = 32 lvPPA‐AD, n = 23 bvAD, n = 19 CBS‐AD). Gaussian mixture modeling was used to harmonize different tau‐PET tracers by transforming tau‐PET standardized uptake value ratios to tau positivity probabilities (a uniform scale ranging from 0% to 100%). Using linear regression, we assessed whether 1) brain regions with stronger functional connectivity showed greater covariance in cross‐sectional and longitudinal tau‐PET and post‐mortem tau pathology, and 2) functional connectivity of tau‐PET epicenters and tau‐PET accumulation epicenters was associated with cross‐sectional and longitudinal tau patterns. Result Tau‐PET epicenters—defined as the 5% brain regions with the highest tau load—aligned with clinical variants, e.g. a posterior pattern in PCA‐AD (“visual AD”) and left‐hemispheric temporal predominance in lvPPA‐AD (“language AD”) (Figure 1). More strongly functionally connected regions showed correlated concurrent tau‐PET levels, which was confirmed with post‐mortem data (Figure 2). Moreover, the connectivity profile of tau‐PET epicenters and accumulation epicenters corresponded to tau‐PET progression patterns (Figure 3). Conclusion Our data are consistent with the hypothesis that tau propagation occurs along functional connections originating from local epicenters, across all AD clinical variants. Since tau proteinopathy is a key driver of neurodegeneration and cognitive decline, this finding may advance personalized medicine and participant‐specific endpoints in clinical trials.
Rationale and design of a randomized, sham-controlled, clinical trial for evaluation of the Edwards APTURE transcatheter shunt system (ALT-FLOW II)
Kereiakes, Dean J, Tedford, Ryan J, Lindenfeld, JoAnn, Gray, William A. , Zahr, Firas, Lurz, Phillip, Hibbert, B., Baron, Suzanne J., Jorde, Ulrich P, Teerlink, John R, Kahwash, Rami , Lilly, S. Mary, Böhm, M, Windecker, S, Butler, Javed, Harrington, Robert A, Tedford, Ryan J. , Hibbert, Benjamin , Jorde, Ulrich P. , Kereiakes, Dean J , Tedford, Ryan J , Zahr, Firas , Hibbert, Benjamin , Teerlink, John R , Kahwash, Rami , Böhm, Michael , Windecker, Stephan , Butler, Javed , Kereiakes, Dean J. , Lindenfeld, JoAnn , Zahr, Firas , Cavalcante, João L. , Lilly, Scott M, Windecker, Stephan , Butler, Javed , Harrington, Robert A.

European Journal of Heart Failure | January 6, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1093/ejhf/xuaf016 | PMID 41771068 Get It

Abstract Aims Heart failure (HF) with preserved (HFpEF) and mildly reduced (HFmrEF) ejection fraction are prevalent, yet frequently underdiagnosed syndromes associated with high morbidity and mortality, impaired quality of life, and escalating healthcare expenditures. Although guideline-directed medications like SGLT2 inhibitors have been shown to reduce the risk of hospitalization and cardiovascular death, their use remains limited and substantial residual risk persists. This trial aims to evaluate the safety and performance of a novel left-atrium-to-coronary-sinus shunt (Edwards APTURE transcatheter shunt system) in HFpEF and HFmrEF patients. Methods ALT-FLOW II is a prospective multi-centre, randomized, sham-controlled, double-blinded (patient and assessor) trial. Approximately 100 symptomatic HF patients aged ≥18 years with left ventricular ejection fraction >40% and exercise pulmonary capillary wedge pressure (PCWP) ≥25 mm Hg with a PCWP to right atrial pressure gradient ≥8 mm Hg will be randomized 1:1 to the APTURE shunt vs sham control. Key exclusion criteria include severe HF, significant valvular disease, and more than mild right ventricular dysfunction. The primary endpoints are the safety of the APTURE device at 30 days and change in workload-corrected PCWP normalized to bodyweight at 6 months. Secondary endpoints include changes in patient-reported outcomes, and hemodynamic and echocardiographic parameters through 5 years. The trial will also explore the impact of the device on short-term cardiac remodelling and intra-cardiac flow patterns using multi-modality imaging. Conclusions The ALT-FLOW II trial will evaluate the safety and performance of the APTURE system in symptomatic HFpEF and HFmrEF patients with elevated left atrial pressure.
Proceedings of the 30th Annual Congress of the International Liver Transplantation Society
Wilson, Elizabeth A. , Khan, Mohammad Qasim , Kyaw, A Mi Mi , Magistri, P., Tejedor, Marta , Kathirvel, Manikandan , Moral, Kenan , Shankar, Sadhana , Mao, Shennen A. , Alconchel, Felipe, Maira, Tommaso Di , Hakeem, Abdul Rahman , Rammohan, Ashwin, Alconchel, Felipe , Tejedor, Marta , Magistri, Paolo , Mao, Shennen A , Alconchel, Felipe , Di Maira, Tommaso , Chadha, Ryan , Rammohan, Ashwin , Wilson, Elizabeth , Shankar, Sadhana , Mathew, Johns Shaji , Patel, Madhukar S. , Syn, Nicholas L. X. , Chadha, Ryan , Khan, Mohammad Qasim

Liver Transplantation | January 5, 2026 | Volume: 32 | Issue: 5 | Pages: 765-778

10.1097/lvt.0000000000000802 | PMID 41490533 Get It

The 2025 Annual Congress of the International Liver Transplantation Society (ILTS), themed “ Advancing Liver Transplantation: Embracing Innovation for the Future ,” was held from May 28 to 31 in Singapore. The meeting offered a comprehensive scientific program, featuring 92 sessions and 7 pre-congress workshops spanning living donor liver transplantation, advanced surgery, anesthesia and critical care, transplant oncology and immunology, basic science, pediatrics, and more. The program emphasized collaboration and innovation to advance patient outcomes in liver transplantation. In this report, the ILTS Vanguard Committee summarizes the key proceedings of the congress.
Cross‐Sectional Studies: Strengths, Limitations, and Methodological Considerations
Baumeister, Sebastian‐Edgar , Kocher, Thomas , Holtfreter, Birte , Holtfreter, Birte , Demmer, Ryan T , Papapanou, Panos N , Demmer, Ryan T.

Journal of Periodontal Research | January 5, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1111/jre.70063 | PMID 41487096 Get It

ABSTRACT Cross‐sectional studies capture health states, exposures, and risk factors at a single time point, providing essential data for estimating disease prevalence and informing public health planning. These studies serve multiple epidemiological purposes: characterizing population health, monitoring temporal trends through repeated surveys, and evaluating interventions via interrupted time series designs. They also offer practical advantages for validating self‐reported measures and creating diagnostic models. Cross‐sectional designs are efficient and well‐suited to descriptive epidemiology, but they have limited utility for causal inference. The simultaneous measurement of exposures and outcomes creates temporal ambiguity that fundamentally constrains etiologic interpretation. However, causal inferences can be strengthened under specific conditions—when temporal sequence is unambiguous (e.g., genetic variants preceding outcomes) or when valid instrumental variables are available. This methodological tutorial equips readers with concepts and tools to critically appraise cross‐sectional studies across the application domains outlined and to design and analyze their own cross‐sectional studies that yield high‐quality epidemiologic descriptions.
ercc6 deficient zebrafish exhibit UV and metronidazole sensitivity, increased oxygen consumption, and impaired hair cell mechanoelectrical transduction which can be restored by the superoxide dismutase mimetic MnTBAP
Herrera, Gabriel A Hernandez, Dugdale, Joseph , Wallace, Jasmine G , Cotter, Ryan P. , Jolliffe, Alyssa M. , Clark, Karl J. , Schimmenti, Lisa A. , Hernandez-Herrera, Gabriel A. , Hernandez Herrera, Gabriel A , Dugdale, Joseph A , Clark, Karl J , Schimmenti, Lisa A , Cotter, Ryan P

Human Molecular Genetics | December 30, 2025 | Volume: 35 | Issue: 4 | Pages: No page available

10.1093/hmg/ddaf203 | PMID 41527836 Get It

Abstract Cockayne Syndrome is an ultra-rare premature aging condition associated with UV sensitivity, neurocognitive decline, retinopathy, metronidazole-induced lethality, and sensorineural hearing loss. In 70% of affected patients, bi-allelic pathogenic variants in ERCC6 are identified. Although the role of ERCC6 in DNA damage repair has been studied, little is known about the mechanism for defective ERCC6 function in clinical findings, particularly hearing loss. To identify the mechanism of disease caused by pathogenic variants in ERCC6, we developed a zebrafish (Danio rerio) ercc6 loss of function model. We assessed survival after UV and metronidazole exposure, measured basal respiration rates, and evaluated mechanoelectrical transduction function and counts of lateral line hair cells. We found that UV exposure significantly reduces ercc6−/− larval viability. Metronidazole treatment results in complete lethality; wildtype controls show nearly complete survival. ercc6−/− embryos have significantly increased oxygen consumption, suggesting abnormal mitochondrial function. Phalloidin staining of lateral line hair cells with and without UV treatment shows no difference in hair cell counts per neuromast between treatment groups. Mechanoelectrical transduction function after UV exposure, measured by FM1–43 uptake, is reduced. Metronidazole lethality is reduced, oxygen consumption rates are restored, and mechanoelectrical transduction function is preserved by treatment with Mn(III)tetrakis(4-benzoic acid)porphyrin Chloride (MnTBAP), a superoxide dismutase mimetic. We propose that defective mitochondrial function and increased reactive oxygen species levels provide a mechanism for hair cell dysfunction in this model of Cockayne Syndrome. These results provide a foundation for further experiments to explore disease mechanisms and treatment modalities for this premature aging condition.