Mouse Studies to Shape Clinical Trials for Mitochondrial Diseases: High Fat Diet in Harlequin Mice

BACKGROUND: Therapeutic options in human mitochondrial oxidative phosphorylation (OXPHOS) diseases have been poorly evaluated mostly because of the scarcity of cohorts and the inter-individual variability of disease progression. Thus, while a high fat diet (HFD) is often recommended, data regarding efficacy are limited. Our objectives were 1) to determine our ability to evaluate therapeutic options in the Harlequin OXPHOS complex I (CI)-deficient mice, in the context of a mitochondrial disease with human hallmarks and 2) to assess the effects of a HFD. METHODS AND FINDINGS: Before launching long and expensive animal studies, we showed that palmitate afforded long-term death-protection in 3 CI-mutant human fibroblasts cell lines. We next demonstrated that using the Harlequin mouse, it was possible to draw solid conclusions on the efficacy of a 5-month-HFD on neurodegenerative symptoms. Moreover, we could identify a group of highly responsive animals, echoing the high variability of the disease progression in Harlequin mice. CONCLUSIONS: These results suggest that a reduced number of patients with identical genetic disease should be sufficient to reach firm conclusions as far as the potential existence of responders and non responders is recognized. They also positively prefigure HFD-trials in OXPHOS-deficient patients

Doxorubicin-induced chronic dilated cardiomyopathy—the apoptosis hypothesis revisited

The chemotherapeutic agent doxorubicin (DOX) has significantly increased survival rates of pediatric and adult cancer patients. However, 10% of pediatric cancer survivors will 10–20 years later develop severe dilated cardiomyopathy (DCM), whereby the exact molecular mechanisms of disease progression after this long latency time remain puzzling. We here revisit the hypothesis that elevated apoptosis signaling or its increased likelihood after DOX exposure can lead to an impairment of cardiac function and cause a cardiac dilation. Based on recent literature evidence, we first argue why a dilated phenotype can occur when little apoptosis is detected. We then review findings suggesting that mature cardiomyocytes are protected against DOX-induced apoptosis downstream, but not upstream of mitochondrial outer membrane permeabilisation (MOMP). This lack of MOMP induction is proposed to alter the metabolic phenotype, induce hypertrophic remodeling, and lead to functional cardiac impairment even in the absence of cardiomyocyte apoptosis. We discuss findings that DOX exposure can lead to increased sensitivity to further cardiomyocyte apoptosis, which may cause a gradual loss in cardiomyocytes over time and a compensatory hypertrophic remodeling after treatment, potentially explaining the long lag time in disease onset. We finally note similarities between DOX-exposed cardiomyocytes and apoptosis-primed cancer cells and propose computational system biology as a tool to predict patient individual DOX doses. In conclusion, combining recent findings in rodent hearts and cardiomyocytes exposed to DOX with insights from apoptosis signal transduction allowed us to obtain a molecularly deeper insight in this delayed and still enigmatic pathology of DC

Circulating microRNAs as novel biomarkers for diabetes mellitus.

Diabetes mellitus is characterized by insulin secretion from pancreatic β cells that is insufficient to maintain blood glucose homeostasis. Autoimmune destruction of β cells results in type 1 diabetes mellitus, whereas conditions that reduce insulin sensitivity and negatively affect β-cell activities result in type 2 diabetes mellitus. Without proper management, patients with diabetes mellitus develop serious complications that reduce their quality of life and life expectancy. Biomarkers for early detection of the disease and identification of individuals at risk of developing complications would greatly improve the care of these patients. Small non-coding RNAs called microRNAs (miRNAs) control gene expression and participate in many physiopathological processes. Hundreds of miRNAs are actively or passively released in the circulation and can be used to evaluate health status and disease progression. Both type 1 diabetes mellitus and type 2 diabetes mellitus are associated with distinct modifications in the profile of miRNAs in the blood, which are sometimes detectable several years before the disease manifests. Moreover, circulating levels of certain miRNAs seem to be predictive of long-term complications. Technical and scientific obstacles still exist that need to be overcome, but circulating miRNAs might soon become part of the diagnostic arsenal to identify individuals at risk of developing diabetes mellitus and its devastating complications

Relationship between quality of life and distress in infertility: a validation study of the Dutch FertiQoL

BACKGROUND: This study examined the relationship between emotional distress as measured by the Hospital Anxiety and Depression Scale (HADS) and the Fertility Quality of Life (FertiQoL) questionnaire. METHODS: The FertiQoL and HADS were distributed to a random sample of 785 patients attending 29 Dutch clinics for medically assisted reproduction. FertiQoL was psychometrically tested for reliability. Pearson's correlations were calculated between subscales of FertiQoL and HADS. Using an independent t-test, differences between patient subgroups were computed for both instruments. The threshold for clinically meaningful depression/anxiety on the HADS subscales was used to ascertain the critical threshold for high distress on the FertiQoL scales. RESULTS: FertiQoL and HADS were completed by 583 patients (response 74%). Reliability of FertiQoL scales was high (reliability coefficient between 0.72 and 0.91). Significant negative correlations were found between FertiQoL subscales and HADS scores for anxiety and depression, ranging from -0.29 to -0.71. Means on FertiQoL scales and HADS scales of couples undergoing an assisted reproductive technology (ART) treatment and a non-ART treatment did not differ significantly. Patients scoring above the HADS threshold for pathology on anxiety had an average FertiQoL score of 58.8, whereas patients exceeding the HADS depression threshold had a FertiQoL total score of 51.9 (range 0-100). CONCLUSIONS: Our study confirms the expected negative relation between quality of life as measured by FertiQoL and anxiety and depression. The data support that FertiQoL reliably measures QoL in women facing infertility. FertiQoL enables clinicians to tailor care more specifically to the patient in a comprehensive way

Predicting dropout in fertility care: a longitudinal study on patient-centredness

Item does not contain fulltextSTUDY QUESTION: Are clinic factors, including patients' experiences with patient-centred care, associated with dropout in fertility care? SUMMARY ANSWER: Clinic factors, including patients' experiences with patient-centred care, are not related to dropout. WHAT IS KNOWN ALREADY: In fertility care, a significant proportion of patients do not achieve pregnancy because they discontinue treatment prematurely. Many studies have tried to identify factors predicting dropout, showing incompatible results. However, these studies mainly focus on factors at the treatment and patient level, while clinic factors have received little attention. STUDY DESIGN, SIZE, DURATION: This prospective, longitudinal study was nested within a large RCT, which aims to improve the level of patient-centredness of Dutch fertility care. Of the 1620 infertile women who were invited to participate, the baseline measurement of the study (T0) included 693 women who completed a questionnaire about their experiences with patient-centred fertility care. The follow-up of the patients was 1 year (T1). PARTICIPANTS/MATERIALS, SETTING, METHODS: All included women suffered from infertility and were undergoing treatment in one of the 32 Dutch clinics involved in the trial. Levels of patient-centredness were determined using the Patient-Centredness Questionnaire-Infertility (PCQ-Infertility) at T0. Meanwhile, a professionals' questionnaire was used to gather additional information on characteristics of the clinic (e.g. the number of patients per year or the presence of a fertility nurse). After 1 year, at T1 measurement, patients completed a questionnaire on their current status in fertility care, including their main reason for discontinuation if applicable. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 693 non-pregnant women completed the questionnaire set at T0 and 534 women (77.1%) provided consent for follow-up. At T1 measurement, 434 women (81.3%) completed the questionnaire and 153 of these women (35.2%) continued treatment while 76 women (17.5%) dropped out. Another 175 women (40.3%) had achieved pregnancy and 30 patients (7.9%) were advised to discontinue treatment for medical reasons. Neither levels of patient-centredness nor the additional clinic characteristics differed significantly between dropouts and compliers. However, patients who did not receive assisted reproduction treatment (ART; e.g. underwent intrauterine insemination, IUI) before they dropped out had significantly lower scores on the PCQ-Infertility subscale 'Respect for patients' values' than patients who continued their treatment [odds ratio (OR) 0.57; 95% confidence interval (CI) 0.34-0.95]. Patients who received ART and, subsequently, dropped out had higher scores on the PCQ-Infertility subscale 'Patient involvement' than those receiving non-ART (OR 2.39; 95% CI 1.02-5.59). LIMITATIONS, REASONS FOR CAUTION: We were not able to follow-up a significant proportion (ca. 19%) of the 1620 women who were invited for T0 measurement, which might have biased our results. We also excluded patients who were still in the diagnostic work-up stage and this might have influenced our results as it is known that patients dropout at this stage. As the PCQ-Infertility was validated in patients who were already undergoing treatment, we decided to focus on this patient group only. WIDER IMPLICATIONS OF THE FINDINGS: The results of this study provide a better insight into those factors influencing dropout from the perspective of factors in the clinic itself. Although most clinic factors were not related to dropout, clinic factors might be of use when predicting dropout for specific patient groups, such as patients receiving ART and non-ART. Future research should involve an exploration of more specific predictors of dropout at the patient, treatment and clinic levels. STUDY FUNDING/COMPETING INTERESTS: This work was supported by Merck Serono, the Netherlands. No competing interests declared