Ovarian cancer G protein-coupled receptor 1 deficiency exacerbates crystal deposition and kidney injury in oxalate nephropathy in female mice

Ovarian cancer G protein-coupled receptor 1 (OGR1) (Gpr68) and G protein-coupled receptor 4 (GPR4) (Gpr4) are proton-activated G protein-coupled receptors that are stimulated upon increased extracellular acidity. These receptors have various physiological and pathophysiological roles in renal acid–base physiology, tissue inflammation, and fibrosis among others. Their function in injured renal tissue, however, remains mostly unclear. To address this, we investigated their role in crystalline nephropathy by increasing the oxalate intake of GPR4 KO and OGR1 KO mice. After 10 days of high-oxalate intake and 4 days of recovery, renal crystal content, histopathology, filtration function, and inflammation were assessed. While GPR4 deficiency did not show major alterations in disease progression, OGR1 KO mice had higher urinary calcium levels and exacerbated crystal accumulation accompanied by decreased creatinine clearance and urea excretion and a decreased presence of regulatory T (Treg) cells in kidney tissue. When lowering the severity of the kidney injury, OGR1 KO mice were more prone to develop crystalline nephropathy. In this setting, OGR1 KO mice displayed an increased activation of the immune system and a higher production of proinflammatory cytokines by T cells and macrophages. Taken together, in the acute setting of oxalate-induced nephropathy, the lack of the proton-activated G protein-coupled receptor (GPCR) GPR4 does not influence disease. OGR1 deficiency, however, increases crystal deposition leading to impaired kidney function. Thus, OGR1 may be important to limit kidney crystal deposition, which might subsequently be relevant for the pathophysiology of oxalate kidney stones or other crystallopathies

Paradoxical antidepressant effects of alcohol are related to acid sphingomyelinase and its control of sphingolipid homeostasis

Alcohol is a widely consumed drug that can lead to addiction and severe brain damage. However, alcohol is also used as self-medication for psychiatric problems, such as depression, frequently resulting in depression-alcoholism comorbidity. Here, we identify the first molecular mechanism for alcohol use with the goal to self-medicate and ameliorate the behavioral symptoms of a genetically induced innate depression. An induced over-expression of acid sphingomyelinase (ASM), as was observed in depressed patients, enhanced the consumption of alcohol in a mouse model of depression. ASM hyperactivity facilitates the establishment of the conditioned behavioral effects of alcohol, and thus drug memories. Opposite effects on drinking and alcohol reward learning were observed in animals with reduced ASM function. Importantly, free-choice alcohol drinking—but not forced alcohol exposure—reduces depression-like behavior selectively in depressed animals through the normalization of brain ASM activity. No such effects were observed in normal mice. ASM hyperactivity caused sphingolipid and subsequent monoamine transmitter hypo-activity in the brain. Free-choice alcohol drinking restores nucleus accumbens sphingolipid- and monoamine homeostasis selectively in depressed mice. A gene expression analysis suggested strong control of ASM on the expression of genes related to the regulation of pH, ion transmembrane transport, behavioral fear response, neuroprotection and neuropeptide signaling pathways. These findings suggest that the paradoxical antidepressant effects of alcohol in depressed organisms are mediated by ASM and its control of sphingolipid homeostasis. Both emerge as a new treatment target specifically for depression-induced alcoholism. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00401-016-1658-6) contains supplementary material, which is available to authorized users

Pijn en neurocognitieve stoornissen: stand van zaken en de weg nog te gaan

The detection and treatment of pain is hampered by cognitive disorders. In this review we discuss the epidemiology of pain in cognitive disorders, and elaborate further on the current state of the art on pain in these populations. We will specifically highlight current gaps and recommendations for the future for the following knowledge domains: 1) Biology and neuropathology, 2) Assessment and evaluation, 3) Treatment and management, and 4) Contextual factors such as the organization and education. We identify the following knowledge gaps: 1) (Biology): Do pain experience and pain expressions change in different types of cognitive disorders, and how? 2) (Assessment): How to recognize, evaluate and assess pain, in case the self-report of pain is no longer reliable? 3) (Treatment): Which treatment possibilities are effective? How can we organize this in an interdisciplinary way? And how to monitor this? How can we ensure proper implementation of pain assessment and treatment in clinical practice? Specifically with regard to non-pharmacological treatment, how can we communicate observations from different disciplines, family members and clinicians to improve the detection of pain as well as treatment monitoring/evaluation? 4) (Contextual): How can we increase knowledge and skills on pain in cognitive impairment within educational training?

Pijn en neurocognitieve stoornissen: stand van zaken en de weg nog te gaan

Cognitieve stoornissen kunnen de beleving van pijn veranderen en de diagnostiek en behandeling bemoeilijken. In deze review wordt vanuit een interdisciplinair perspectief de epidemiologie van pijn bij cognitieve stoornissen en de stand van zaken besproken, en samengevat waar de kennishiaten nog liggen. Dit wordt gedaan vanuit vier domeinen, namelijk 1) biologie en neuropathologie, 2) beoordeling en assessment, 3) behandeling en management, en 4) contextuele factoren zoals organisatie en opleiding. De kennishiaten bij deze 4 domeinen zijn: 1) (Biologie): Hoe verandert de pijnervaring en de uiting van pijn bij de verschillende vormen van cognitieve stoornissen? Wat zijn de oorzaak en de gevolgen van pijn in deze groepen? 2) (Assessment): Hoe herkennen, beoordelen en meten we pijn goed, als zelfrapportage niet betrouwbaar is? 3) (Behandeling): Welke behandelingen voor pijn zijn effectief? Hoe kun je die goed interdisciplinair uitvoeren? Hoe zorgen we voor goede implementatie van pijn meten en pijnbehandeling? Vooral ook van niet-farmacologisch behandelen, hoe kunnen we observaties tussen verschillende disciplines, of tussen familie en zorgverleners, beter communiceren zodat herkenning van pijn, en monitoring/evaluatie van behandeling wordt verbeterd? 4) (Contextueel): Wat kunnen we in het onderwijs doen om meer begrip, kennis en vaardigheden op dit gebied te ontwikkelen