J Neuroinflammation. 2015 Aug 12;12:145. doi: 10.1186/s12974-015-0364-y.

ABSTRACT

BACKGROUND: It has recently become evident that activating/inhibitory cell surface immune receptors play a critical role in regulating immune and inflammatory processes in the central nervous system (CNS). The immunoreceptor CD300f expressed on monocytes, neutrophils, and mast cells modulates inflammation, phagocytosis, and outcome in models of autoimmune demyelination, allergy, and systemic lupus erythematosus. On the other hand, a finely regulated inflammatory response is essential to induce regeneration after injury to peripheral nerves since hematogenous macrophages, together with resident macrophages and de-differentiated Schwann cells, phagocyte distal axonal and myelin debris in a well-orchestrated inflammatory response. The possible roles and expression of CD300f and its ligands have not been reported under these conditions.

METHODS: By using quantitative PCR (QPCR) and CD300f-IgG2a fusion protein, we show the expression of CD300f and its ligands in the normal and crush injured sciatic nerve. The putative role of CD300f in peripheral nerve regeneration was analyzed by blocking receptor-ligand interaction with the same CD300f-IgG2a soluble receptor fusion protein in sciatic nerves of Thy1-YFP-H mice injected at the time of injury. Macrophage M1/M2 polarization phenotype was also analyzed by CD206 and iNOS expression.

RESULTS: We found an upregulation of CD300f mRNA and protein expression after injury. Moreover, the ligands are present in restricted membrane patches of Schwann cells, which remain stable after the lesion. The lesioned sciatic nerves of Thy1-YFP-H mice injected with a single dose of CD300f-IgG2a show long lasting effects on nerve regeneration characterized by a lower number of YFP-positive fibres growing into the tibial nerve after 10 days post lesion (dpl) and a delayed functional recovery when compared to PBS- or IgG2a-administered control groups. Animals treated with CD300f-IgG2a show at 10 dpl higher numbers of macrophages and CD206-positive cells and lower levels of iNOS expression than both control groups. At later time points (28 dpl), increased numbers of macrophages and iNOS expression occur.

CONCLUSIONS: Taken together, these results show that the pair CD300f ligand is implicated in Wallerian degeneration and nerve regeneration by modulating both the influx and phenotype of macrophages.

PMID:26259611 | PMC:PMC4531482 | DOI:10.1186/s12974-015-0364-y

FEBS Lett. 2015 Nov 14;589(22):3479-91. doi: 10.1016/j.febslet.2015.07.031. Epub 2015 Jul 29.

ABSTRACT

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous, pleiotropic disorder, characterized by both congenital and late onset defects. From the analysis of the mutational burden in patients to the functional characterization of the BBS proteins, this syndrome has become a model for both understanding oligogenic patterns of inheritance and the biology of a particular cellular organelle: the primary cilium. Here we briefly review the genetics of BBS to then focus on the function of the BBS proteins, not only in the context of the cilium but also highlighting potential extra-ciliary roles that could be relevant to the etiology of the disorder. Finally, we provide an overview of how the study of this rare syndrome has contributed to the understanding of cilia biology and how this knowledge has informed on the cellular basis of different clinical manifestations that characterize BBS and the ciliopathies.

PMID:26231314 | DOI:10.1016/j.febslet.2015.07.031

Gen Comp Endocrinol. 2015 Oct 1;222:158-66. doi: 10.1016/j.ygcen.2015.06.015. Epub 2015 Jul 2.

ABSTRACT

Secretoneurin (SN) in the preoptic area and pituitary of mammals and fish has a conserved close association with the vasopressin and oxytocin systems, members of a peptide family that are key in the modulation of sexual and social behaviors. Here we show the presence of SN-immunoreactive cells and projections in the brain of the electric fish, Brachyhypopomus gauderio. Secretoneurin colocalized with vasotocin (AVT) and isotocin in cells and fibers of the preoptic area. In the rostral pars distalis of the pituitary, many cells were both SN and prolactin-positive. In the hindbrain, at the level of the command nucleus of the electric behavior (pacemaker nucleus; PN), some of SN-positive fibers colocalized with AVT. We also explored the potential neuromodulatory role of SN on electric behavior, specifically on the rate of the electric organ discharge (EOD) that signals arousal, dominance and subordinate status. Each EOD is triggered by the command discharge of the PN, ultimately responsible for the basal EOD rate. SN modulated diurnal basal EOD rate in freely swimming fish in a context-dependent manner; determined by the initial value of EOD rate. In brainstem slices, SN partially mimicked the in vivo behavioral effects acting on PN firing rate. Taken together, our results suggest that SN may regulate electric behavior, and that its effect on EOD rate may be explained by direct action of SN at the PN level through either neuroendocrine and/or endocrine mechanisms.

PMID:26141148 | DOI:10.1016/j.ygcen.2015.06.015

Cell Tissue Res. 2015 Dec;362(3):557-68. doi: 10.1007/s00441-015-2223-7. Epub 2015 Jun 18.

ABSTRACT

Tissue injury triggers a complex network of cellular and molecular responses. Although cell migration and proliferation are the most conspicuous, several other responses, such as apoptosis and increased protease activity, are necessary for a proper restitution of the tissue. In this work, we study the leukocyte elastase inhibitor (LEI) expression during wound healing of bovine corneal endothelial monolayers in culture. LEI is a multifunctional protein with anti-protease and anti-apoptotic activity. When properly cleaved, it is transformed into L-DNase II, a pro-apoptotic enzyme and translocated to the nucleus. We found that early after injury LEI increases its protein and mRNA expressions, without nuclear translocation and returns to basal levels immediately after wound closure. This increase is blocked by N-acetylcysteine, suggesting that production of reactive oxygen species immediately after wounding is involved in the LEI increase. Another finding of this work is that there is an acidification of the cells at the wound border which, in contrast to other cell types, does not determine nuclear translocation of the protein. Taken together, the results of this work suggest that the function of LEI during wound healing is related to its activity as a protease inhibitor and/or to its anti-apoptotic activity.

PMID:26085342 | DOI:10.1007/s00441-015-2223-7

Mol Ther Methods Clin Dev. 2014 Oct 15;1:14047. doi: 10.1038/mtm.2014.47. eCollection 2014.

ABSTRACT

Traumatic brain injury (TBI) remains as one of the leading causes of mortality and morbidity worldwide and there are no effective treatments currently available. Gene therapy applications have emerged as important alternatives for the treatment of diverse nervous system injuries. New strategies are evolving with the notion that each particular pathological condition may require a specific vector. Moreover, the lack of detailed comparative studies between different vectors under similar conditions hampers the selection of an ideal vector for a given pathological condition. The potential use of lentiviral vectors versus several modular protein-based nanovectors was compared using a controlled cortical impact model of TBI under the same gene therapy conditions. We show that variables such as protein/DNA ratio, incubation volume, and presence of serum or chloroquine in the transfection medium impact on both nanovector formation and transfection efficiency in vitro. While lentiviral vectors showed GFP protein 1 day after TBI and increased expression at 14 days, nanovectors showed stable and lower GFP transgene expression from 1 to 14 days. No toxicity after TBI by any of the vectors was observed as determined by resulting levels of IL-1β or using neurological sticky tape test. In fact, both vector types induced functional improvement per se.

PMID:26015985 | PMC:PMC4362363 | DOI:10.1038/mtm.2014.47

Reprod Fertil Dev. 2015 May 20. doi: 10.1071/RD14460. Online ahead of print.

ABSTRACT

This study analysed the temporal association between ovarian cyst development induced by neonatal androgenisation and sympathetic innervation. Neonatal rats (postnatal Days 1 to 5) were treated with testosterone or dihydrotestosterone and the effects were evaluated at postnatal Days 20, 40, 90 or 180. Ovulation rate, number of cystic follicles and density of sympathetic fibres were analysed. The effects of surgical denervation or gonadotrophin stimulation were also assessed. Rats exposed to testosterone showed no oestrous cycle activity and did not ovulate, maintaining a polycystic ovarian morphology at all ages studied. Also, a significant increase in ovarian density of noradrenergic fibres was detected at postnatal Days 90 and 180. Sympathectomy was unable to re-establish ovarian activity; however, human chorionic gonadotrophin stimulation was enough to induce ovulation. The impact of dihydrotestosterone on ovarian function was less noticeable, showing the coexistence of corpora lutea and cystic structures without changes in sympathetic innervation. Our findings suggest that a remodelling of ovarian sympathetic innervation occurs as a response to modifications in the pattern of follicular growth induced by testosterone. A role of sympathetic innervation in the maintenance of the polycystic condition is suggested.

PMID:25989716 | DOI:10.1071/RD14460

PLoS One. 2015 Apr 30;10(4):e0123928. doi: 10.1371/journal.pone.0123928. eCollection 2015.

ABSTRACT

CMRF35-like molecule-1 (CLM-1) belongs to a receptor family mainly expressed in myeloid cells that include activating and inhibitory receptors. CLM-1 contains two ITIMs and a single immunoreceptor tyrosine-based switch motif (ITSM), although also displays a binding site for p85α regulatory subunit of PI3K. By using murine primary microglial cultures, we show the presence of all CLM members in microglial cells and characterize the expression of CLM-1 both in basal conditions and during microglial activation. The TLR4 agonist lipopolysaccharide (LPS) and the TLR3 agonist polyinosinic-polycytidylic acid (Poly I:C) induce an increase in microglial CLM-1 mRNA levels in vitro, whereas the TLR2/6 heterodimer agonist peptidoglycan (PGN) produces a marked decrease. In this study we also describe a new soluble isoform of CLM-1 that is detected at mRNA and protein levels in basal conditions in primary microglial cultures. Interestingly, CLM-1 engagement enhances the transcription of the pro-inflammatory mediators TNFα, COX-2 and NOS-2 in microglial cells challenged with LPS. These results reveal that CLM-1 can acts as a co-activating receptor and suggest that this receptor could play a key role in the regulation of microglial activation.

PMID:25927603 | PMC:PMC4415817 | DOI:10.1371/journal.pone.0123928

Biotechnol Adv. 2015 Mar-Apr;33(2):277-87. doi: 10.1016/j.biotechadv.2015.02.004. Epub 2015 Feb 16.

ABSTRACT

The increasing incidence of diseases affecting the central nervous system (CNS) demands the urgent development of efficient drugs. While many of these medicines are already available, the Blood Brain Barrier and to a lesser extent, the Blood Spinal Cord Barrier pose physical and biological limitations to their diffusion to reach target tissues. Therefore, efforts are needed not only to address drug development but specially to design suitable vehicles for delivery into the CNS through systemic administration. In the context of the functional and structural versatility of proteins, recent advances in their biological fabrication and a better comprehension of the physiology of the CNS offer a plethora of opportunities for the construction and tailoring of plain nanoconjugates and of more complex nanosized vehicles able to cross these barriers. We revise here how the engineering of functional proteins offers drug delivery tools for specific CNS diseases and more transversally, how proteins can be engineered into smart nanoparticles or 'artificial viruses' to afford therapeutic requirements through alternative administration routes.

PMID:25698504 | DOI:10.1016/j.biotechadv.2015.02.004

Reprod Biol. 2014 Dec;14(4):289-92. doi: 10.1016/j.repbio.2014.07.002. Epub 2014 Aug 8.

ABSTRACT

Electron microscopy analysis performed in five infertile human subjects after sperm selection by swim-up followed by magnetic activated cell sorting (MACS) demonstrated a decrease in the number of spermatozoa with characteristics compatible with cell death. However, no significant differences were found when the swim-up/MACS semen fraction was compared with swim-up fraction alone.

PMID:25454495 | DOI:10.1016/j.repbio.2014.07.002

Free Radic Biol Med. 2014 May;70:204-13. doi: 10.1016/j.freeradbiomed.2014.02.019. Epub 2014 Feb 26.

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by motor neuron degeneration that ultimately results in progressive paralysis and death. Growing evidence indicates that mitochondrial dysfunction and oxidative stress contribute to motor neuron degeneration in ALS. To further explore the hypothesis that mitochondrial dysfunction and nitroxidative stress contribute to disease pathogenesis at the in vivo level, we assessed whether the mitochondria-targeted antioxidant [10-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)decyl]triphenylphosphonium methane sulfonate (MitoQ) can modify disease progression in the SOD1(G93A) mouse model of ALS. To do this, we administered MitoQ (500 µM) in the drinking water of SOD1(G93A) mice from a time when early symptoms of neurodegeneration become evident at 90 days of age until death. This regime is a clinically plausible scenario and could be more easily translated to patients as this corresponds to initiating treatment of patients after they are first diagnosed with ALS. MitoQ was detected in all tested tissues by liquid chromatography/mass spectrometry after 20 days of administration. MitoQ treatment slowed the decline of mitochondrial function, in both the spinal cord and the quadriceps muscle, as measured by high-resolution respirometry. Importantly, nitroxidative markers and pathological signs in the spinal cord of MitoQ-treated animals were markedly reduced and neuromuscular junctions were recovered associated with a significant increase in hindlimb strength. Finally, MitoQ treatment significantly prolonged the life span of SOD1(G93A) mice. Our results support a role for mitochondrial nitroxidative damage and dysfunction in the pathogenesis of ALS and suggest that mitochondria-targeted antioxidants may be of pharmacological use for ALS treatment.

PMID:24582549 | DOI:10.1016/j.freeradbiomed.2014.02.019

Neuroscience. 2014 Jan 31;258:347-54. doi: 10.1016/j.neuroscience.2013.11.021. Epub 2013 Nov 21.

ABSTRACT

The intrinsic properties of spherical neurons play a fundamental role in the sensory processing of self-generated signals along a fast electrosensory pathway in electric fish. Previous results indicate that the spherical neuron's intrinsic properties depend mainly on the presence of two resonant currents that tend to clamp the voltage near the resting potential. Here we show that these are: a low-threshold potassium current blocked by 4-aminopyridine and a mixed cationic current blocked by cesium chloride. We also show that the low-threshold potassium current also causes the long refractory period, explaining the necessary properties that implement the dynamic filtering of the self-generated signals previously described. Comparative data from other fish and from the auditory system indicate that other single spiking onset neurons might differ in the channel repertoire observed in the spherical neurons of Gymnotus omarorum.

PMID:24269939 | DOI:10.1016/j.neuroscience.2013.11.021

J Exp Biol. 2013 Jul 1;216(Pt 13):2380-92. doi: 10.1242/jeb.082651.

ABSTRACT

This review deals with the question: what is the relationship between the properties of a neuron and the role that the neuron plays within a given neural circuit? Answering this kind of question requires collecting evidence from multiple neuron phenotypes and comparing the role of each type in circuits that perform well-defined computational tasks. The focus here is on the spherical neurons in the electrosensory lobe of the electric fish Gymnotus omarorum. They belong to the one-spike-onset phenotype expressed at the early stages of signal processing in various sensory modalities and diverse taxa. First, we refer to the one-spike neuron intrinsic properties, their foundation on a low-threshold K(+) conductance, and the potential roles of this phenotype in different circuits within a comparative framework. Second, we present a brief description of the active electric sense of weakly electric fish and the particularities of spherical one-spike-onset neurons in the electrosensory lobe of G. omarorum. Third, we introduce one of the specific tasks in which these neurons are involved: the trade-off between self- and allo-generated signals. Fourth, we discuss recent evidence indicating a still-undescribed role for the one-spike phenotype. This role deals with the blockage of the pathway after being activated by the self-generated electric organ discharge and how this blockage favors self-generated electrosensory information in the context of allo-generated interference. Based on comparative analysis we conclude that one-spike-onset neurons may play several functional roles in animal sensory behavior. There are specific adaptations of the neuron's 'response function' to the circuit and task. Conversely, the way in which a task is accomplished depends on the intrinsic properties of the neurons involved. In short, the role of a neuron within a circuit depends on the neuron and its functional context.

PMID:23761463 | DOI:10.1242/jeb.082651

Neurol Res. 2013 Apr;35(3):308-19. doi: 10.1179/1743132812Y.0000000139. Epub 2012 Dec 26.

ABSTRACT

BACKGROUND: The zinc finger protein A20 is an ubiquitinating/deubiquitinating enzyme essential for the termination of inflammatory reactions through the inhibition of nuclear factor kappaB (NF-kappaB) signaling. Moreover, it also shows anti-apoptotic activities in some cell types and proapoptotic/pronecrotic effects in others. Although it is known that the regulation of inflammatory and cell death processes are critical in proper brain functioning and that A20 mRNA is expressed in the CNS, its role in the brain under physiological and pathological conditions is still unknown.

METHODS: In the present study, we have evaluated the effects of A20 overexpression in mixed cortical cultures in basal conditions: the in vivo pattern of endogenous A20 expression in the control and N-methyl-d-aspartate (NMDA) excitotoxically damaged postnatal day 9 immature rat brain, and the post-injury effects of A20 overexpression in the same lesion model.

RESULTS: Our results show that overexpression of A20 in mixed cortical cultures induced significant neuronal death by decreasing neuronal cell counts by 45 ± 9%. in vivo analysis of endogenous A20 expression showed widespread expression in gray matter, mainly in neuronal cells. However, after NMDA-induced excitotoxicity, neuronal A20 was downregulated in the neurodegenerating cortex and striatum at 10-24 hours post-lesion, and it was re-expressed at longer survival times in reactive astrocytes located mainly in the lesion border. When A20 was overexpressed in vivo 2 hours after the excitotoxic damage, the lesion volume at 3 days post-lesion showed a significant increase (20.8 ± 7.0%). No A20-induced changes were observed in the astroglial response to injury.

CONCLUSIONS: A20 is found in neuronal cells in normal conditions and is also expressed in astrocytes after brain damage, and its overexpression is neurotoxic for cortical neurons in basal mixed neuron-glia culture conditions and exacerbates postnatal brain excitotoxic damage.

PMID:23336395 | DOI:10.1179/1743132812Y.0000000139

PLoS One. 2012;7(4):e34776. doi: 10.1371/journal.pone.0034776. Epub 2012 Apr 3.

ABSTRACT

Mitochondrial dysfunction is one of the pathogenic mechanisms that lead to neurodegeneration in Amyotrophic Lateral Sclerosis (ALS). Astrocytes expressing the ALS-linked SOD1(G93A) mutation display a decreased mitochondrial respiratory capacity associated to phenotypic changes that cause them to induce motor neuron death. Astrocyte-mediated toxicity can be prevented by mitochondria-targeted antioxidants, indicating a critical role of mitochondria in the neurotoxic phenotype. However, it is presently unknown whether drugs currently used to stimulate mitochondrial metabolism can also modulate ALS progression. Here, we tested the disease-modifying effect of dichloroacetate (DCA), an orphan drug that improves the functional status of mitochondria through the stimulation of the pyruvate dehydrogenase complex activity (PDH). Applied to astrocyte cultures isolated from rats expressing the SOD1(G93A) mutation, DCA reduced phosphorylation of PDH and improved mitochondrial coupling as expressed by the respiratory control ratio (RCR). Notably, DCA completely prevented the toxicity of SOD1(G93A) astrocytes to motor neurons in coculture conditions. Chronic administration of DCA (500 mg/L) in the drinking water of mice expressing the SOD1(G93A) mutation increased survival by 2 weeks compared to untreated mice. Systemic DCA also normalized the reduced RCR value measured in lumbar spinal cord tissue of diseased SOD1(G93A) mice. A remarkable effect of DCA was the improvement of grip strength performance at the end stage of the disease, which correlated with a recovery of the neuromuscular junction area in extensor digitorum longus muscles. Systemic DCA also decreased astrocyte reactivity and prevented motor neuron loss in SOD1(G93A) mice. Taken together, our results indicate that improvement of the mitochondrial redox status by DCA leads to a disease-modifying effect, further supporting the therapeutic potential of mitochondria-targeted drugs in ALS.

PMID:22509356 | PMC:PMC3318006 | DOI:10.1371/journal.pone.0034776

Horm Metab Res. 2012 Jul;44(8):569-76. doi: 10.1055/s-0032-1306343. Epub 2012 Mar 27.

ABSTRACT

Steroid hormones modulate a wide array of physiological processes including development, metabolism, and reproduction in various species. It is generally believed that these biological effects are predominantly mediated by their binding to specific intracellular receptors resulting in conformational change, dimerization, and recruitment of coregulators for transcription-dependent genomic actions (classical mechanism). In addition, to their cognate ligands, intracellular steroid receptors can also be activated in a "ligand-independent" manner by other factors including neurotransmitters. Recent studies indicate that rapid, nonclassical steroid effects involve extranuclear steroid receptors located at the membrane, which interact with cytoplasmic kinase signaling molecules and G-proteins. The current review deals with various mechanisms that function together in an integrated manner to promote hormone-dependent actions on the central and sympathetic nervous systems.

PMID:22454239 | PMC:PMC3646380 | DOI:10.1055/s-0032-1306343

BMC Res Notes. 2012 Jan 26;5:69. doi: 10.1186/1756-0500-5-69.

ABSTRACT

BACKGROUND: Complex traits like cancer, diabetes, obesity or schizophrenia arise from an intricate interaction between genetic and environmental factors. Complex disorders often cluster in families without a clear-cut pattern of inheritance. Genomic wide association studies focus on the detection of tens or hundreds individual markers contributing to complex diseases. In order to test if a subset of single nucleotide polymorphisms (SNPs) from candidate genes are associated to a condition of interest in a particular individual or group of people, new techniques are needed. High-resolution melting (HRM) analysis is a new method in which polymerase chain reaction (PCR) and mutations scanning are carried out simultaneously in a closed tube, making the procedure fast, inexpensive and easy. Preterm birth (PTB) is considered a complex disease, where genetic and environmental factors interact to carry out the delivery of a newborn before 37 weeks of gestation. It is accepted that inflammation plays an important role in pregnancy and PTB.

METHODS: Here, we used real time-PCR followed by HRM analysis to simultaneously identify several gene variations involved in inflammatory pathways on preterm labor. SNPs from TLR4, IL6, IL1 beta and IL12RB genes were analyzed in a case-control study. The results were confirmed either by sequencing or by PCR followed by restriction fragment length polymorphism.

RESULTS: We were able to simultaneously recognize the variations of four genes with similar accuracy than other methods. In order to obtain non-overlapping melting temperatures, the key step in this strategy was primer design. Genotypic frequencies found for each SNP are in concordance with those previously described in similar populations. None of the studied SNPs were associated with PTB.

CONCLUSIONS: Several gene variations related to the same inflammatory pathway were screened through a new flexible, fast and non expensive method with the purpose of analyzing their association to PTB. It can easily be used for simultaneously analyze any set of SNPs, either as the first choice for new association studies or as a complement to large-scale genotyping analysis. Given that inflammatory pathway is in the base of several diseases, it is potentially useful to analyze a broad range of disorders.

PMID:22280494 | PMC:PMC3298535 | DOI:10.1186/1756-0500-5-69

Reproduction. 2012 Feb;143(2):183-93. doi: 10.1530/REP-11-0056. Epub 2011 Nov 11.

ABSTRACT

Oestradiol (E(2)) is a key hormone in the regulation of reproductive processes. The aims of this work were a) to examine the distributions of oestrogen receptor α (ERα) and ERβ in the neurons of the superior mesenteric ganglion (SMG) in the oestrus stage by immunohistochemistry, b) to demonstrate whether E(2) in the SMG modifies progesterone (P(4)), androstenedione (A(2)) and nitrite release in the ovarian compartment on oestrus day and c) to demonstrate whether E(2) in the ganglion modifies the activity and gene expression in the ovary of the steroidogenic enzymes 3β-hydroxysteroid dehydrogenase (3β-HSD) and 20α-hydroxysteroid dehydrogenase (20α-HSD). The ex vivo SMG-ovarian nervous plexus-ovary system was used. E(2), tamoxifen (Txf) and E(2) plus Txf were added in the ganglion to measure ovarian P(4) release, while E(2) alone was added to measure ovarian A(2) and nitrites release. Immunohistochemistry revealed cytoplasmic ERα immunoreactivity only in the neural somas in the SMG. E(2) increased ovarian P(4) and A(2) release at 15, 30 and 60 min but decreased nitrites. The activity and gene expression of 3β-HSD increased, while the activity and gene expression of 20α-HSD did not show changes with respect to the control. Txf in the ganglion diminished P(4) release only at 60 min. E(2) plus Txf in the ganglion reverted the effect of E(2) alone and the inhibitory effect of Txf. The results of this study demonstrate that ERα activation in the SMG has an impact on ovarian steroidogenesis in rats, thus providing evidence for the critical role of peripheral system neurons in the control of ovarian functions under normal and pathological conditions.

PMID:22080140 | DOI:10.1530/REP-11-0056

Proc Natl Acad Sci U S A. 2011 Nov 1;108(44):18126-31. doi: 10.1073/pnas.1110689108. Epub 2011 Oct 18.

ABSTRACT

Motoneuron loss and reactive astrocytosis are pathological hallmarks of amyotrophic lateral sclerosis (ALS), a paralytic neurodegenerative disease that can be triggered by mutations in Cu-Zn superoxide dismutase (SOD1). Dysfunctional astrocytes contribute to ALS pathogenesis, inducing motoneuron damage and accelerating disease progression. However, it is unknown whether ALS progression is associated with the appearance of a specific astrocytic phenotype with neurotoxic potential. Here, we report the isolation of astrocytes with aberrant phenotype (referred as "AbA cells") from primary spinal cord cultures of symptomatic rats expressing the SOD1(G93A) mutation. Isolation was based on AbA cells' marked proliferative capacity and lack of replicative senescence, which allowed oligoclonal cell expansion for 1 y. AbA cells displayed astrocytic markers including glial fibrillary acidic protein, S100β protein, glutamine synthase, and connexin 43 but lacked glutamate transporter 1 and the glial progenitor marker NG2 glycoprotein. Notably, AbA cells secreted soluble factors that induced motoneuron death with a 10-fold higher potency than neonatal SOD1(G93A) astrocytes. AbA-like aberrant astrocytes expressing S100β and connexin 43 but lacking NG2 were identified in nearby motoneurons, and their number increased sharply after disease onset. Thus, AbA cells appear to be an as-yet unknown astrocyte population arising during ALS progression with unprecedented proliferative and neurotoxic capacity and may be potential cellular targets for slowing ALS progression.

PMID:22010221 | PMC:PMC3207668 | DOI:10.1073/pnas.1110689108

Brain Pathol. 2012 May;22(3):318-28. doi: 10.1111/j.1750-3639.2011.00537.x. Epub 2011 Oct 31.

ABSTRACT

It is well known that cell surface immune receptors play a critical role in regulating immune and inflammatory processes in the central nervous system (CNS). We have analyzed the function of cluster of differentiation (CD)300f immunoreceptor in a model of excitotoxic rat brain damage. First, to explore the presence of endogenous ligand(s) for this receptor we used a human CD300f-Ig soluble protein and confocal microscopy, showing specific staining mainly in CNS white matter and on the surface of oligodendrocytes and certain astrocytes. Next, we demonstrated in a model of in vivo rat brain excitotoxic damage that the overexpression of human CD300f induced a significant reduction in the lesion volume. To validate these results, we cloned the rat ortholog of CD300f protein (rCD300f). The overexpression of rCD300f receptor had a comparable neuroprotective effect after the acute brain injury and a similar CNS staining pattern when stained with the rCD300f-Ig soluble protein. Interestingly, when we analyzed the expression pattern of rCD300f in brain cells by quantitative polymerase chain reaction and immunohistochemistry, we detected the expression of CD300f as expected in microglial cells, but also in oligodendrocytes and neurons. These data suggest that the neuroprotective role of CD300f would be the result of a complex network of cell interactions.

PMID:21951326 | PMC:PMC8092960 | DOI:10.1111/j.1750-3639.2011.00537.x

Andrologia. 2012 Feb;44(1):59-65. doi: 10.1111/j.1439-0272.2010.01106.x. Epub 2011 May 19.

ABSTRACT

Sperm morphology has consistently been the best indicator of male fertility. Transmission electron microscopy currently provides the most information on the subcellular details of sperm structure. Recently, assessment of sperm DNA damage has been employed to assess fertility potential. The purpose of this work was to link sperm DNA damage, evaluated by an intercalated fluorescent dye, with the structural characteristics of sperm. Conventional semen analysis was performed on samples from men undergoing fertility evaluation. Thirty men were evaluated and assigned to three subgroups based on strict criteria for sperm morphology: normal morphology (>14% normal forms), intermediate morphology (5-14% normal forms), and poor morphology (<5% normal forms). By quantifying acridine orange-positive cells and ultrastructural sperm defects, we found that the poor morphology pattern group showed a positive association between sperm carrying damaged DNA and the percentage of sperm nucleus with vacuoles (P = 0.01). No statistically significant correlations were established in other ultrastructural characteristics of sperm, including immature chromatin, lytic changes, or abnormal sperm tails. These results suggest that zones without chromatin in the sperm nucleus reflect underlying chromosomal or DNA defects in severe teratozoospermic men. This association should be considered in the evaluation of male fertility.

PMID:21592172 | DOI:10.1111/j.1439-0272.2010.01106.x