An undesired side effect of cancer treatment is potential subfertility or infertility. Timely cryopreservation of semen is the best modality to ensure fertility. This retrospective data analysis established the usage rate of cryopreserved semen from cancer patients. Pubertal and post-pubertal patients who could become infertile as a result of cancer (treatment) were offered the option to cryopreserve semen prior to treatment. Of the 898 patients who cryopreserved their semen in our hospital, 96 (10.7%) used this for assisted reproductive technology. The live birth rates for intrauterine insemination, in-vitro fertilization, intracytoplasmic sperm injection and cryopreserved embryo transfer were 13%, 29%, 32% and 17%, respectively. Of all couples involved, 77% achieved parenthood, i.e. 60 of the 78 patients (with complete follow-up) fathered at least one child.

Myotonic dystrophy protein kinase (DMPK) is a Ser/Thr-type protein kinase with unknown function, originally identified as the product of the gene that is mutated by triplet repeat expansion in patients with myotonic dystrophy type 1 (DM1). Alternative splicing of DMPK transcripts results in multiple protein isoforms carrying distinct C termini. Here, we demonstrate by expressing individual DMPKs in various cell types, including C 2 C 12 and DMPK ؊/؊ myoblast cells, that unique sequence arrangements in these tails control the specificity of anchoring into intracellular membranes. Mouse DMPK A and C were found to associate specifically with either the endoplasmic reticulum (ER) or the mitochondrial outer membrane, whereas the corresponding human DMPK A and C proteins both localized to mitochondria. Expression of mouse and human DMPK A-but not C-isoforms in mammalian cells caused clustering of ER or mitochondria. Membrane association of DMPK isoforms was resistant to alkaline conditions, and mutagenesis analysis showed that proper anchoring was differentially dependent on basic residues flanking putative transmembrane domains, demonstrating that DMPK tails form unique tail anchors. This work identifies DMPK as the first kinase in the class of tail-anchored proteins, with a possible role in organelle distribution and dynamics.Myotonic dystrophy protein kinase (DMPK) was discovered more than a decade ago as the product of the gene that is altered by (CTG) n repeat expansion in patients with myotonic dystrophy type 1 (DM1) (6, 13, 31). Study of DMPK has thus far been aimed primarily at its normal physiological role, because the coding information of the DMPK gene remains unaltered in DM1 patients and disease-causing effects of mutation appear to act primarily at the RNA rather than at the protein level (28,40). Bioinformatic, biochemical, and cell biological studies demonstrated that DMPK is an evolutionarily new protein found only in skeletal, cardiac, and smooth muscle and epithelial cells in mammals (reference 45 and our unpublished data).The protein is related to Rho-kinase type protein kinases (14, 26) and belongs to the family of AGC-kinases, with myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK␣/␤) (29) and human p160 ROCK , rat ROK␣, Caenorhabditis elegans LET-502, and murine citron Rho-interacting kinase (54) as its closest homologues. These kinases modulate the actin cytoskeleton by regulating myosin phosphatase activity or by directly phosphorylating the myosin regulatory light chain, thereby affecting stress fiber formation, smooth muscle contraction, and cytokinesis (2, 11, 39).Recent findings revealed that DMPK may participate in a variety of cellular processes. As potential substrates for DMPK, phospholemman (34), the ␤-subunit of DHPR (51), MKBP (49), CUGBP/hNab50 (41), and the myosin phosphatase targeting subunit 1 (MYPT1) (35, 54) have been identified. The latter finding could point to a role for DMPK in cytoskeletal movement or intracellular transport dynamics, similar to the function of...

The central melanocortin (MC) system mediates its effects on food intake via MC3 (MC3R) and MC4 receptors (MC4R). Although the role of MC4R in meal size determination, satiation, food preference, and motivation is well established, the involvement of MC3R in the modulation of food intake has been less explored. Here, we investigated the role of MC3R on the incentive motivation for food, which is a crucial component of feeding behavior. Dopaminergic neurons within the ventral tegmental area (VTA) have a crucial role in the motivation for food. We here report that MC3Rs are expressed on VTA dopaminergic neurons and that pro-opiomelanocortinergic (POMC) neurons in the arcuate nucleus of the hypothalamus (Arc) innervate these VTA dopaminergic neurons. Our findings show that intracerebroventricular or intra-VTA infusion of the selective MC3R agonist γMSH increases responding for sucrose under a progressive ratio schedule of reinforcement, but not free sucrose consumption in rats. Furthermore, ex vivo electrophysiological recordings show increased VTA dopaminergic neuronal activity upon γMSH application. Consistent with a dopamine-mediated effect of γMSH, the increased motivation for sucrose after intra-VTA infusion of γMSH was blocked by pretreatment with the dopamine receptor antagonist α-flupenthixol. Taken together, we demonstrate an Arc POMC projection onto VTA dopaminergic neurons that modulates motivation for palatable food via activation of MC3R signaling.

The striatum harbors two neuronal populations that enable action selection. One population represents the striatonigral pathway, expresses the dopamine receptor D1 (DRD1) and promotes the execution of motor programs, while the other population represents the striatopallidal pathway, expresses the dopamine receptor D2 (DRD2) and suppresses voluntary activity. The two populations integrate distinct sensorimotor, cognitive, and emotional information streams and their combined activity enables the selection of adaptive behaviors. Characterization of these populations is critical to the understanding of their role in action selection, because it aids the identification of the molecular mechanisms that separate them. To that end, we used fluorescent in situ hybridization to quantify the percentage of striatal cells that (co)express dopaminergic receptors and receptors of the cannabinoid, melanocortin or opioid neurotransmitters systems. Our main findings are that the cannabinoid 1 receptor is equally expressed on both populations with a gradient from dorsal to ventral striatum, that the opioid receptors have a preference for expression with either the DRD1 or DRD2 and that the melanocortin 4 receptor (MC4R) is predominantly expressed in ventral parts of the striatum. In addition, we find that the level of MC4R expression determines its localization to either the DRD1 or the DRD2 population. Thereby, we provide insight into the sensitivity of the two dopaminoceptive populations to these neurotransmitters and progress the understanding of the mechanisms that enable action selection.

The role of the melanocortin (MC) system in feeding behavior is well established. Food intake is potently suppressed by central infusion of the MC 3/4 receptor agonist α-melanocyte stimulating hormone (α-MSH), whereas the MC 3/4 receptor inverse-agonist Agouti Related Peptide (AGRP) has the opposite effect. MC receptors are widely expressed in both hypothalamic and extra-hypothalamic brain regions, including nuclei involved in food reward and motivation, such as the nucleus accumbens (NAc) and the ventral tegmental area. This suggests that MCs modulate motivational aspects of food intake. To test this hypothesis, rats were injected intracerebroventricularly with α-MSH or AGRP and their motivation for sucrose was tested under a progressive ratio schedule of reinforcement. Food motivated behavior was dose-dependently decreased by α-MSH. Conversely, AGRP increased responding for sucrose, an effect that was blocked by pretreatment with the dopamine receptor antagonist α-flupenthixol. In contrast to progressive ratio responding, free intake of sucrose remained unaltered upon α-MSH or AGRP infusion. In addition, we investigated whether the effects of α-MSH and AGRP on food motivation were mediated by the NAc shell. In situ hybridization of MC3 and MC4 receptor expression confirmed that the MC4 receptor was expressed throughout the NAc, and injection of α-MSH and AGRP into the NAc shell caused a decrease and an increase in motivation for sucrose, respectively. These data show that the motivation for palatable food is modulated by MC4 receptors in the NAc shell, and demonstrate cross-talk between the MC and dopamine system in the modulation of food motivation.