Neuroblastoma (NB) is a pediatric malignancy characterized by a marked reduction in aerobic energy metabolism. Recent preclinical data indicate that targeting this metabolic phenotype by a ketogenic diet (KD), especially in combination with calorie restriction, slows tumor growth and enhances metronomic cyclophosphamide (CP) therapy of NB xenografts. Because calorie restriction would be contraindicated in most cancer patients, the aim of the present study was to optimize the KD such that the tumors are sensitized to CP without the need of calorie restriction. In a NB xenograft model, metronomic CP was combined with KDs of different triglyceride compositions and fed to CD1-nu mice ad libitum. Metronomic CP in combination with a KD containing 8-carbon medium-chain triglycerides exerted a robust anti-tumor effect, suppressing growth and causing a significant reduction of tumor blood-vessel density and intratumoral hemorrhage, accompanied by activation of AMP-activated protein kinase in NB cells. Furthermore, the KDs caused a significant reduction in the serum levels of essential amino acids, but increased those of serine, glutamine and glycine. Our data suggest that targeting energy metabolism by a modified KD may be considered as part of a multimodal treatment regimen to improve the efficacy of classic anti-NB therapy.

The regulatory peptide galanin is broadly distributed in the central- and peripheral nervous systems as well as in non-neuronal tissues, where it exerts its diverse physiological functions via three G-protein-coupled receptors (GAL 1-3 -R). Regulatory peptides are important mediators of the cross-communication between the nervous- and immune systems and have emerged as a focus of new therapeutics for a variety of inflammatory diseases. Studies on inflammatory animal models and immune cells revealed both pro- and anti-inflammatory functions of galanin. Here, we probed specific immune-related functions of the galanin system and found galanin and GAL 1 -R and GAL 2 -R mRNA to be expressed in a range of human immune cells. In particular, macrophages displayed differentiation- and polarization-dependent expression of galanin and its receptors. Exposure to exogenous galanin affected the cytokine/chemokine expression profile of macrophages differently, depending on their differentiation and polarization, and mainly modulated the expression of chemokines (CCL2, CCL3, CCL5 and CXCL8) and anti-inflammatory cytokines (TGF-β, IL-10 and IL-1Ra), especially in type-1 macrophages. Cytokine/chemokine expression levels in interferon-gamma- and lipopolysaccharide-polarized macrophages were upregulated whereas in unpolarized macrophages they were downregulated upon galanin treatment for 20 hours. This study illuminates the regulation of important cytokines/chemokines in macrophages by galanin, depending on specific cell activation.

The neuropeptide galanin (GAL) is widely distributed in the central and peripheral nervous systems. It is a modulator of various physiological and pathological processes, and it mediates its effects via three G protein-coupled receptors (GAL 1-3 receptors). A role for GAL as a modulator of mood and anxiety was suggested, because GAL and its receptors are highly expressed in limbic brain structures of rodents. In recent years, numerous studies of animal models have suggested an involvement of GAL and GAL 1 and GAL 2 receptors in anxiety-and depression-related behavior. However, to date, there is sparse literature implicating GAL 3 receptors in behavioral functions. Therefore, we studied the behavior of GAL 3 receptor-deficient (GAL 3 -KO) mice to elucidate whether GAL 3 receptors are involved in mediating behavior-associated actions of GAL. The GAL 3 -KO mouse line exhibited normal breeding and physical development. In addition to behavioral tests, phenotypic characterization included analysis of hematology, amino acid profiles, metabolism, and sudomotor function. In contrast to WT littermates, male GAL 3 -KO mice exhibited an anxietylike phenotype in the elevated plus maze, open field, and light/ dark box tests, and they were less socially affiliated than WT animals to a stranger mouse in a social interaction test. In conclusion, our data suggest involvement of GAL 3 receptors in GAL-mediated effects on mood, anxiety, and behavior, making it a possible target for alternative treatment strategies for mood disorders.T hirty years ago, Tatemoto et al. (1) isolated the neuropeptide galanin (GAL), a 29-aa (30-aa in humans) peptide, from porcine intestine. The peptide is highly conserved throughout evolution and found in many other species. GAL is widely distributed in the CNS and peripheral nervous system, and it has a variety of biological and physiological functions, ranging from energy homeostasis, reproduction, and feeding to cognition and learning (2). In the murine brain, GAL mRNA is extensively expressed in the hypothalamic and brainstem areas. The highest expression levels were observed in the preoptic, periventricular, and dorsomedial hypothalamic nuclei; bed nucleus of the stria terminalis (BNST); medial and lateral amygdala; locus coeruleus; and nucleus of the solitary tract (3). Furthermore, GAL coexists with the serotonin and norepinephrine systems in the rodent brain and acts as an inhibitory neuromodulator of norepinephrine, serotonin, dopamine, glutamate, and acetylcholine function (4). The expression pattern and neuromodulatory functions of GAL suggest a role for this neuropeptide in mood disorders like anxiety and depression. Accordingly, administration of GAL via the intracerebroventricular (i.c.v.) route or into the dopaminergic ventral tegmental area induced depression-like behavior in the rat forced swim test (FST) (5, 6). Several studies in GAL-overexpressing transgenic mice reported an increased depression-like behavior in the FST (7, 8) but found no differences in anxiety-related behavior und...

Vertebrate respiratory chain complex III consists of eleven subunits. Mutations in five subunits either mitochondrial (MT-CYB) or nuclear (CYC1, UQCRC2, UQCRB, and UQCRQ) encoded have been reported. Defects in five further factors for assembly (TTC19, UQCC2, and UQCC3) or iron-sulphur cluster loading (BCS1L and LYRM7) cause complex III deficiency. Here, we report a second patient with UQCC2 deficiency. This girl was born prematurely; pregnancy was complicated by intrauterine growth retardation and oligohydramnios. She presented with respiratory distress syndrome, developed epileptic seizures progressing to status epilepticus, and died at day 33. She had profound lactic acidosis and elevated urinary pyruvate. Exome sequencing revealed two homozygous missense variants in UQCC2, leading to a severe reduction of UQCC2 protein. Deficiency of complexes I and III was found enzymatically and on the protein level. A review of the literature on genetically distinct complex III defects revealed that, except TTC19 deficiency, the biochemical pattern was very often a combined respiratory chain deficiency. Besides complex III, typically, complex I was decreased, in some cases complex IV. In accordance with previous observations, the presence of assembled complex III is required for the stability or assembly of complexes I and IV, which might be related to respirasome/supercomplex formation.