Rescue of Photoreceptor Degeneration by Curcumin in Transgenic Rats with P23H Rhodopsin Mutation

The P23H mutation in the rhodopsin gene causes rhodopsin misfolding, altered trafficking and formation of insoluble aggregates leading to photoreceptor degeneration and autosomal dominant retinitis pigmentosa (RP). There are no effective therapies to treat this condition. Compounds that enhance dissociation of protein aggregates may be of value in developing new treatments for such diseases. Anti-protein aggregating activity of curcumin has been reported earlier. In this study we present that treatment of COS-7 cells expressing mutant rhodopsin with curcumin results in dissociation of mutant protein aggregates and decreases endoplasmic reticulum stress. Furthermore we demonstrate that administration of curcumin to P23H-rhodopsin transgenic rats improves retinal morphology, physiology, gene expression and localization of rhodopsin. Our findings indicate that supplementation of curcumin improves retinal structure and function in P23H-rhodopsin transgenic rats. This data also suggest that curcumin may serve as a potential therapeutic agent in treating RP due to the P23H rhodopsin mutation and perhaps other degenerative diseases caused by protein trafficking defects

H2AX phosphorylation screen of cells from radiosensitive cancer patients reveals a novel DNA double-strand break repair cellular phenotype

BACKGROUND: About 1-5% of cancer patients suffer from significant normal tissue reactions as a result of radiotherapy (RT). It is not possible at this time to predict how most patients' normal tissues will respond to RT. DNA repair dysfunction is implicated in sensitivity to RT particularly in genes that mediate the repair of DNA double-strand breaks (DSBs). Phosphorylation of histone H2AX (phosphorylated molecules are known as gammaH2AX) occurs rapidly in response to DNA DSBs, and, among its other roles, contributes to repair protein recruitment to these damaged sites. Mammalian cell lines have also been crucial in facilitating the successful cloning of many DNA DSB repair genes; yet, very few mutant cell lines exist for non-syndromic clinical radiosensitivity (RS).\ud \ud METHODS: Here, we survey DNA DSB induction and repair in whole cells from RS patients, as revealed by gammaH2AX foci assays, as potential predictive markers of clinical radiation response.\ud \ud RESULTS: With one exception, both DNA focus induction and repair in cell lines from RS patients were comparable with controls. Using gammaH2AX foci assays, we identified a RS cancer patient cell line with a novel ionising radiation-induced DNA DSB repair defect; these data were confirmed by an independent DNA DSB repair assay.\ud \ud CONCLUSION: gammaH2AX focus measurement has limited scope as a pre-RT predictive assay in lymphoblast cell lines from RT patients; however, the assay can successfully identify novel DNA DSB repair-defective patient cell lines, thus potentially facilitating the discovery of novel constitutional contributions to clinical RS

Dedicated anticoagulation management protocols in fragility femoral fracture care – a source of significant variance and limited effectiveness in improving time to surgery: The hip and femoral fracture anticoagulation surgical timing evaluation (HASTE) study

\ua9 2024 The Author(s)Introduction: Approximately 20 % of femoral fragility fracture patients take anticoagulants, typically warfarin or Direct Oral AntiCoagulant (DOAC). These can impact timing of surgery affecting patient survival. Due to several possible approaches and numerous factors to consider in the preoperative workup of anticoagulated patients, potential for variations in clinical practice exist. Some hospitals employ dedicated anticoagulation management protocols to address this issue, and to improve time to surgery. This study aimed to determine the proportion of hospitals with such protocols, compare protocol guidance between hospitals, and evaluate the effectiveness of protocols in facilitating prompt surgery. Methods: Data was prospectively collected through a collaborative, multicentre approach involving hospitals across the UK. Femoral fragility fracture patients aged ≥60 years and admitted to hospital between 1st May to 31st July 2023 were included. Information from dedicated anticoagulation management protocols were collated on several domains relating to perioperative care including administration of reversal agents and instructions on timing of surgery as well as others. Logistic regression was used to evaluate effects of dedicated protocols on time to surgery. Results: Dedicated protocols for management of patients taking warfarin and DOACs were present at 41 (52.6 %) and 43 (55.1 %) hospitals respectively. For patients taking warfarin, 39/41 (95.1 %) protocols specified the dose of vitamin k and the most common was 5 milligrams intravenously (n=21). INR threshold values for proceeding to surgery varied between protocols; 1.5 (n=28), 1.8 (n=6), and 2 (n=6). For patients taking DOACs, 35/43 (81.4 %) and 8/43 (18.6 %) protocols advised timing of surgery based on renal function and absolute time from last dose respectively. Analysis of 10,197 patients from 78 hospitals showed fewer patients taking DOACs received surgery within 36 h of admission at hospitals with a dedicated protocol compared to those without (adjusted OR 0.73, 95% CI 0.54–0.99, p=0.040), while there were no differences among patients taking warfarin (adjusted OR 1.64, 95% CI 0.75–3.57, p=0.219). Conclusions: Around half of hospitals employed a dedicated anticoagulation management protocol for femoral fragility fracture patients, and substantial variation was observed in guidance between protocols. Dedicated protocols currently being used at hospitals were ineffective at improving the defined targets for time to surgery