A new paradigm of neuromuscular electrical stimulation for the quadriceps femoris muscle.

PURPOSE: Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for quadriceps muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the quadriceps femoris muscle in healthy subjects. METHODS: Ten healthy subjects completed two experimental sessions (c-NMES and m-NMES), that were randomly presented in a cross-over design. Maximal electrically evoked force at pain threshold, self-reported discomfort at different levels of evoked force, and fatigue-induced force declines during and following a series of 20 NMES contractions were compared between c-NMES and m-NMES. RESULTS: m-NMES resulted in greater evoked force (P < 0.05) and lower discomfort in comparison to c-NMES (P < 0.05-0.001), but fatigue time course and magnitude did not differ between the two conditions. CONCLUSIONS: The use of quadriceps m-NMES appears legitimate for (re)training purposes because it generated stronger contractions and was less discomfortable than c-NMES (due to multiple current pathways and/or lower current density with larger electrodes).

Combining MAR elements and transposable vectors for more reliable transgene integration and expression

Integration without cytotoxic effects and long-term expression of a transgene constitutes a major challenge in gene therapy and biotechnology applications. In this context, transposons represent an attractive system for gene transfer because of their ability to promote efficient integration of a transgene in a variety of cell lines. However, the transgene integration can lead to insertional mutagenesis and/or unstable transgene expression by epigenetic modifications. These unwanted events may be limited by the use of chromatin control elements called MARs (matrix attachment regions). Indeed, the insertion of these DNA elements next to the transgene usually results in higher and more stable expression by maintaining transgene chromatin in an active configuration and preventing gene silencing. In this study, we tested if the inclusion of the MAR 1-68 in the piggyBac transposon system may lead to efficient and safer transgene integration and ensure reliable stable and long-term expression of a transgene. The MAR-containing transposon construct was tested in CHO cells, for biotechnology applications, and in mesoangioblast cells that can differentiate into muscle cells and are important candidates for potential stem cell therapies of myopathies. We showed that the addition of the MAR 1 -68 in the piggyBac transposon did not interfere with transposition, thereby maintaining high frequency of transgene integrations in these cells. Moreover, the MAR allowed higher transgene expression from fewer transposon integration events. We also found that enriched transgene-expressing cell populations could be obtained without the need of selection pressure. Since antibiotic-enforced selection protocols often result in a higher integrated copy number and mosaic expression patterns, this strategy could benefit many applications in which a low copy number of integrated transgenes and antibiotic-free conditions are desired. In addition, the intramuscular transplantation of mouse tibialis anterior muscles with mesoangioblasts containing the transposon led to widespread and sustained myofiber transgene expression after differentiation of these cells in vivo. These findings indicated that piggyBac vectors may provide a viable approach to achieve stable gene transfer in the context of Duchenne muscular dystrophy therapy. - L'intégration sans effets cytotoxiques et l'expression à long terme d'un transgène constituent un défi majeur en thérapie génique et en biotechnologie. Dans ce contexte, les transposons représentent un système attrayant pour le transfert de gènes en raison de leur capacité à promouvoir l'intégration efficace d'un transgène dans une variété de lignées cellulaires. Toutefois, l'intégration d'un transgène peut conduire à une mutagénèse insertionnelle et/ou à une expression instable due au silençage du transgène suite à des modifications épigénétiques. Ces événements indésirables de silençage génique peuvent être diminués par l'utilisation d'éléments de contrôle de la chromatine appelés MAR (matrix attachment region). En effet, l'insertion de ces éléments d'ADN à proximité du transgène se traduit généralement par une expression plus élevée et plus stable de celui-ci, en permettant le maintien d'une chromatine dans une configuration active autour du transgène et en empêchant l'inactivation du gène. Dans cette étude, nous avons testé si l'inclusion du MAR 1-68 dans le système transposon piggyBac peut améliorer l'efficacité d'intégration de façon sécuritaire et l'expression à long terme d'un transgène. Le transposon contenant l'élément MAR a été testé dans les cellules CHO, couramment utilisées en biotechnologie, et dans des cellules progénitrices appelées mésoangioblastes, qui peuvent se différencier en cellules musculaires, et qui constituent ainsi des candidats prometteurs pour la thérapie à partir de cellules souches de patients souffrant de myopathie. Nous avons montré que l'addition du MAR 1-68 dans le transposon piggyBac n'interfère pas avec la transposition et permet de maintenir une fréquence élevée d'intégration du transgène dans ces deux types cellulaires. De plus, il semble que cette association mène à une meilleure expression du transgène à partir de peu d'événements d'intégration du transposon. En outre, ces populations enrichies en cellules exprimant de façon stable le transgène ont pu être obtenues sans avoir recours à une pression de sélection. Etant donné que les protocoles de sélection basée sur l'utilisation d'antibiotiques conduisent souvent à un nombre plus élevé de copies intégrées et à la variégation de l'expression du transgène et qu'ils impliquent une longue culture in vitro, cette stratégie pourrait profiter à des applications pour lesquelles on souhaite un faible nombre de copies intégrées et/ou l'utilisation d'antibiotiques n'est pas souhaitable. De plus, la transplantation intramusculaire de mésoangioblastes contenant le transposon dans le muscle tibial antérieur de souris a conduit, après la différentiation de ces cellules in vivo, à une expression constante et étendue du transgène dans les myofibres. Ces résultats indiquent que les vecteurs piggyBac pourraient fournir une approche viable pour assurer un transfert de gènes stables dans le contexte d'un traitement de la dystrophic musculaire de Duchenne.

A comprehensive analysis of gene expression profiles in distal parts of the mouse renal tubule.

The distal parts of the renal tubule play a critical role in maintaining homeostasis of extracellular fluids. In this review, we present an in-depth analysis of microarray-based gene expression profiles available for microdissected mouse distal nephron segments, i.e., the distal convoluted tubule (DCT) and the connecting tubule (CNT), and for the cortical portion of the collecting duct (CCD; Zuber et al., Proc Natl Acad Sci USA 106:16523-16528, 2009). Classification of expressed transcripts in 14 major functional gene categories demonstrated that all principal proteins involved in maintaining the salt and water balance are represented by highly abundant transcripts. However, a significant number of transcripts belonging, for instance, to categories of G-protein-coupled receptors or serine/threonine kinases exhibit high expression levels but remain unassigned to a specific renal function. We also established a list of genes differentially expressed between the DCT/CNT and the CCD. This list is enriched by genes related to segment-specific transport functions and by transcription factors directing the development of the distal nephron or collecting ducts. Collectively, this in silico analysis provides comprehensive information about relative abundance and tissue specificity of the DCT/CNT and the CCD expressed transcripts and identifies new candidate genes for renal homeostasis.

Neurochemical profile of the mouse hypothalamus using in vivo 1H MRS at 14.1T.

The hypothalamus plays an essential role in the central nervous system of mammals by among others regulating glucose homeostasis, food intake, temperature, and to some extent blood pressure. Assessments of hypothalamic metabolism using, e.g. (1)H MRS in mouse models can provide important insights into its function. To date, direct in vivo (1)H MRS measurements of hypothalamus have not been reported. Here, we report that in vivo single voxel measurements of mouse hypothalamus are feasible using (1)H MRS at 14.1T. Localized (1)H MR spectra from hypothalamus were obtained unilaterally (2-2.2 microL, VOI) and bilaterally (4-4.4 microL) with a quality comparable to that of hippocampus (3-3.5 microL). Using LCModel, a neurochemical profile consisting of 21 metabolites was quantified for both hypothalamus and hippocampus with most of the Cramér-Rao lower bounds within 20%. Relative to the hippocampus, the hypothalamus was characterized by high gamma-aminobutryric acid and myo-inositol, and low taurine concentrations. When studying transgenic mice with no glucose transporter isoform 8 expressed, small metabolic changes were observed, yet glucose homeostasis was well maintained. We conclude that a specific neurochemical profile of mouse hypothalamus can be measured by (1)H MRS which will allow identifying and following metabolic alterations longitudinally in the hypothalamus of genetic modified models.

Dysfunction of epithelial sodium transport: from human to mouse.

The highly amiloride-sensitive epithelial sodium channel (ENaC) is an apical membrane constituent of cells of many salt-absorbing epithelia. In the kidney, the functional relevance of ENaC expression has been well established. ENaC mediates the aldosterone-dependent sodium reabsorption in the distal nephron and is involved in the regulation of blood pressure. Mutations in genes encoding ENaC subunits are causative for two human inherited diseases: Liddle's syndrome, a severe form of hypertension associated with ENaC hyperfunction, and pseudohypoaldosteronism (PHA-1), a salt-wasting syndrome caused by decreased ENaC function. Transgenic mouse technologies provide a useful tool to study the role of ENaC in vivo. Different mouse lines have been established in which each of the ENaC subunits was affected. The phenotypes observed in these mice demonstrated that each subunit is essential for survival and for regulation of sodium transport in kidney and colon. Moreover, the alpha subunit plays a specific role in the control of fluid absorption in the airways at birth. Such mice can now be used to study the role of ENaC in various organs and can serve as models to understand the pathophysiology of these human diseases.

Differential distribution of MAP1a and aldolase c in adult mouse cerebellum.

MAP1a is a microtubule-associated protein with an apparent molecular weight of 360 kDa that is found in the axonal and dendritic processes of neurons. Two monoclonal anti-MAP1a antibodies anti-A and anti-BW6, revealed different epitope distributions in the adult mouse cerebellum. Anti-A stained Purkinje and granule cells uniformly throughout the cerebellum. In contrast, anti-BW6 selectively stained the dendriites of a subset of Purkinje cells, revealing parasagittal bands of immunoreactivity in the molecular layer. The compartmentation of the BW6 epitope was compared to the Purkine cells as revealed by immunostaining with anti-zebrin II, a well known antigen expressed selectively by bands of Purkinje cells. The anti-BW6 staining pattern was complementary to the zebrin II bands, the zebrin II- Purkinjke cells having BW6+ dendrites. These results demonstrate that MAP1a is present in two forms in the mouse cerebellum, one of which is segregated into parasagittal bands. This may indicate a unique MAP1a isoform or may reflect differences in the metabolic states of Purkinje cell classes, and regional differences in their functions.

Assessing dystrophies and other muscle diseases at the nanometer scale by atomic force microscopy.

AIM: Atomic force microscopy nanoindentation of myofibers was used to assess and quantitatively diagnose muscular dystrophies from human patients. MATERIALS & METHODS: Myofibers were probed from fresh or frozen muscle biopsies from human dystrophic patients and healthy volunteers, as well as mice models, and Young's modulus stiffness values were determined. RESULTS: Fibers displaying abnormally low mechanical stability were detected in biopsies from patients affected by 11 distinct muscle diseases, and Young's modulus values were commensurate to the severity of the disease. Abnormal myofiber resistance was also observed from consulting patients whose muscle condition could not be detected or unambiguously diagnosed otherwise. DISCUSSION & CONCLUSION: This study provides a proof-of-concept that atomic force microscopy yields a quantitative read-out of human muscle function from clinical biopsies, and that it may thereby complement current muscular dystrophy diagnosis.

Techniques d'évaluation de la force des muscles respiratoires. [Techniques for assessing respiratory muscle strength.]

La faiblesse des muscles respiratoires peut entraîner une dyspnée, un encombrement bronchique et une insuffisance respiratoire potentiellement fatale. L'évaluation de la force musculaire respiratoire s'impose donc dans les affections neuro-musculaires, mais également dans les situations de dyspnée inexpliquée par une première évaluation cardiaque et pulmonaire. À la spirométrie, une faiblesse musculaire est suspectée sur la base de la boucle débit-volume montrant un débit de pointe émoussé et une fin prématurée de l'expiration. Une diminution importante de la capacité vitale en position couchée suggère une paralysie diaphragmatique. La force inspiratoire est mesurée par la pression inspiratoire maximale (PImax) contre une quasi-occlusion des voies aériennes. Ce test relativement difficile est d'interprétation délicate en cas de collaboration insuffisante. La mesure de la pression nasale sniff (SNIP) est une alternative utile, car elle élimine le problème des fuites autour de l'embout buccal et la réalisation du reniflement est facile. De même, la pression trans-diaphragmatique sniff mesure la force du diaphragme au moyen de sondes oesophagienne et gastrique. En cas de collaboration insuffisante, on peut recourir à la stimulation magnétique des nerfs phréniques qui induit une contraction non-volontaire du diaphragme. La force expiratoire est mesurée par la pression expiratoire maximale (PEmax) contre une quasi-occlusion. La force disponible pour tousser est mesurée par la pression gastrique à la toux, ou plus simplement par le débit de pointe à la toux. Chez les patients à risque, la mesure de la force des muscles respiratoires permet d'instaurer à temps une assistance ventilatoire ou à la toux.

Binding of low concentration of peptide to H-2Kd produced in insect cells requires mouse beta 2-microglobulin co-expression.

A recombinant baculovirus expressing the murine class I MHC heavy chain H-2Kd cDNA under the transcriptional control of Autografa californica nuclear polyhedrosis virus (AcNPV) polyhedrin promoter has been isolated and used to infect Sf9 lepidopteran cells either alone or in association with a previously isolated virus expressing mouse beta 2-microglobulina (beta 2-ma). When infected with the heavy chain-encoding virus alone, H-2Kd was produced in a beta 2-m-free conformation detected on the surface of infected cells by conformation-independent antibodies. When Sf9 cells were co-infected with both viruses, approximately 10% of the heavy chain pool was engaged in the formation of native heterodimeric MHC class I molecules, which were glycosylated and transported to the cell surface as demonstrated by radio-binding experiments and flow cytometry. The assembly of the recombinant class I molecule was dependent on peptide, since heterodimer formation was brought about by H-2Kd-specific peptide ligands both in vivo, upon incubation with dually infected cells, and in vitro, in cell-free detergent extracts. In addition, a change in heavy chain conformation was brought about upon incubation with high concentrations (100 microM) of an H-2Kd-restricted octapeptide epitope from Plasmodium berghei. Furthermore, using low concentrations (3 nM) of a photoaffinity label derivative of this peptide, we show direct binding to cells co-expressing class I heavy chain and mouse beta 2-m but not to cells expressing free heavy chain only.

Antigen-secretory IgA immune complexes are retro-transported into mouse Peyer's patches: immunotargeting to dendritic cells

RÉSUMÉ Les plaques de Peyer (PP) représentent le site d'entrée majeur des pathogènes au niveau des muqueuses intestinales. Après avoir traversé la cellule M, l'antigène est pris en charge par les cellules dendritiques (DC) de la région sub-épithéliale du dôme des PP. Ces dernières activent une réponse immunitaire qui conduit à la production de l'IgA de sécrétion (SIgA), l'anticorps majeur au niveau muqueux. Des études précédentes dans notre laboratoire ont démontré qu'après administration de SIgA dans des anses intestinales de souris, les SIgA se lient spécifiquement aux cellules M, entrent dans les PP, et sont éventuellement internalisées par les DC. Le but de ce travail est de comprendre la relevance biologique de l'entrée des SIgA dans les PP et leur relevance physiologique dans l'homéostasie mucosale. Dans un premier temps, nous avons montré en utilisant une méthode de purification optimisée basée sur une isolation magnétique, que, en plus des DC myéloïdes (CD11c+/CD11b+) et des DC lymphoïdes (CD11c+/CD8+), les PP de souris contiennent un nouveau sous-type de DC exprimant les marqueurs CD11c et CD19. L'utilisation de la microscopie confocale nous a permis de démontrer que les DC myéloïdes internalisent des SIgA, contrairement aux DC lymphoïdes qui n'interagissent pas avec les SIgA, alors que le nouveau sous-type de DC exprimant CD19 lie les SIgA. En plus, nous avons démontré qu'aucune des DC de rate, de ganglion bronchique ou de ganglion inguinal interagit avec les SIgA. Dans le but d'explorer si les SIgA peuvent délivrer des antigènes aux DC des PP in vivo, nous avons administré des complexes immunitaires formés de Shigella flexneri complexées à des SIgA, dans des anses intestinales de souris. Nous avons observé une entrée dans les PP, suivie d'une migration vers les ganglions mésentériques drainants, contrairement aux Shigella flexneri seules, qui n'infectent pas la souris par la voie intestinale. Shigella flexneri délivrée par SIgA n'induit pas de destruction tissulaire au niveau de l'intestin. En plus de l'exclusion immunitaire, ces résultats suggèrent un nouveau rôle des SIgA, qui consiste à transporter des antigènes à l'intérieur des PP dans un contexte non-inflammatoire. RÉSUMÉ DESTINÉ À UN LARGE PUBLIC L'intestin a pour rôle principal d'absorber les nutriments digérés tout au long du tube digestif, et de les faire passer dans le compartiment intérieur sanguin. Du fait de son exposition chronique avec un monde extérieur constitué d'aliments et de bactéries, l'intestin est un endroit susceptible aux infections et a donc besoin d'empêcher l'entrée de microbes. Pour cela, l'intestin est tapissé de "casernes" appelées les plaques de Peyer, qui appartiennent à un système de défense appelé système immunitaire muqueux. Les plaques de Peyer sont composées de différents types de cellules, ayant pour rôle de contrôler l'entrée de microbes et de développer une réaction immunitaire lors d'infection. Cette réaction immunitaire contre les microbes (antigènes) débute par la prise en charge de l'antigène par des sentinelles, les cellules dendritiques. L'antigène est préparé de façon à être reconnu par d'autres cellules appelées lymphocytes T capables d'activer d'autres cellules, les lymphocytes B. La réaction immunitaire résulte dans la production par les lymphocytes B d'un anticorps spécifique appelé IgA de sécrétion (SIgA) au niveau de la lumière intestinale. De manière classique, le rôle de SIgA au niveau de la lumière intestinale consiste à enrober les microbes et donc exclure leur entrée dans le compartiment intérieur. Dans ce travail, nous avons découvert une nouvelle fonction des SIgA qui consiste à introduire des antigènes dans les plaques de Peyer, et de les diriger vers les cellules dendritiques. Sachant que les SIgA sont des anticorps qui ne déclenchent pas de réactions de défense violentes dites inflammatoires, l'entrée des antigènes via SIgA serait en faveur d'une défense intestinale maîtrisée sans qu'il y ait d'inflammation délétère. Ces résultats nous laissent supposer que l'entrée d'antigènes via SIgA pourrait conduire le système immunitaire muqueux à reconnaître ces antigènes de manière appropriée. Ce mécanisme pourrait expliquer les désordres immunitaires de types allergiques et maladies auto-immunitaires que l'on rencontre chez certaines personnes déficientes en IgA, chez qui cette lecture d'antigènes de manière correcte serait inadéquate. ABSTRACT Peyer's patches (PP) represent the primary site for uptake and presentation of ingested antigens in the intestine. Antigens are sampled by M cells, which pass them to underlying antigen-presenting cells including dendritic cells (DC). This leads to the induction of mucosal T cell response that is important for the production of secretory IgA (SIgA), the chief antibody at mucosal surfaces. Previous studies in the laboratory have shown that exogenous SIgA administrated into mouse intestinal loop binds specifically to M cells, enter into PP, and is eventually internalized by DC. The aim of this work is to understand the biological significance of the SIgA uptake by PP DC and its physiological relevance for mucosal homeostasis. As a first step, we have shown by using an optimized MACS method that, in addition to the CD11c+/CD11b+ (myeloid DC) and CD11c+/CD8+ (lymphoid DC) subtypes, mouse PP contain a novel DC subtype exhibiting both CD11c and CD19 markers. By using a combination of MACS isolation and confocal microscopy, we have demonstrated that in contrast to the lymphoid DC which do not interact with SIgA, the myeloid DC internalize SIgA, while the CD19+ subtype binds SIgA on its surface. Neither spleen DC, nor bronchial-lymph node DC, nor inguinal lymph node DC exhibit such a binding specificity. To test whether SIgA could deliver antigens to PP DC in vivo, we administered SIgA-Shigella flexneri immune complexes into mouse intestinal loop containing a PP. We found that (i) SIgA-Shigella flexneri immune complexes enter the PP and are internalized by sub-epithelial dome PP DC, in contrast to Shigella flexneri alone that does not penetrate the intestinal epithelia in mice, (ii) immune complexes migrate to the draining mesenteric lymph node, (iii) Shigella flexneri carried via SIgA do not induce intestinal tissue destruction. Our results suggest that in addition to immune exclusion, SIgA transports antigens back to the PP under non-inflammatory conditions.

NCoR1 is a conserved physiological modulator of muscle mass and oxidative function.

Transcriptional coregulators control the activity of many transcription factors and are thought to have wide-ranging effects on gene expression patterns. We show here that muscle-specific loss of nuclear receptor corepressor 1 (NCoR1) in mice leads to enhanced exercise endurance due to an increase of both muscle mass and of mitochondrial number and activity. The activation of selected transcription factors that control muscle function, such as MEF2, PPARβ/δ, and ERRs, underpins these phenotypic alterations. NCoR1 levels are decreased in conditions that require fat oxidation, resetting transcriptional programs to boost oxidative metabolism. Knockdown of gei-8, the sole C. elegans NCoR homolog, also robustly increased muscle mitochondria and respiration, suggesting conservation of NCoR1 function. Collectively, our data suggest that NCoR1 plays an adaptive role in muscle physiology and that interference with NCoR1 action could be used to improve muscle function.

The relationship between monocarboxylate transporters 1 and 4 expression in skeletal muscle and endurance performance in athletes

The purpose of this study was to examine the relationship between skeletal muscle monocarboxylate transporters 1 and 4 (MCT1 and MCT4) expression, skeletal muscle oxidative capacity and endurance performance in trained cyclists. Ten well-trained cyclists (mean +/- SD; age 24.4 +/- 2.8 years, body mass 73.2 +/- 8.3 kg, VO(2max) 58 +/- 7 ml kg(-1) min(-1)) completed three endurance performance tasks [incremental exercise test to exhaustion, 2 and 10 min time trial (TT)]. In addition, a muscle biopsy sample from the vastus lateralis muscle was analysed for MCT1 and MCT4 expression levels together with the activity of citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD). There was a tendency for VO(2max) and peak power output obtained in the incremental exercise test to be correlated with MCT1 (r = -0.71 to -0.74; P < 0.06), but not MCT4. The average power output (P (average)) in the 2 min TT was significantly correlated with MCT4 (r = -0.74; P < 0.05) and HAD (r = -0.92; P < 0.01). The P (average) in the 10 min TT was only correlated with CS activity (r = 0.68; P < 0.05). These results indicate the relationship between MCT1 and MCT4 as well as cycle TT performance may be influenced by the length and intensity of the task.

Comparative gene prediction in human and mouse

The completion of the sequencing of the mouse genome promises to help predict human genes with greater accuracy. While current ab initio gene prediction programs are remarkably sensitive (i.e., they predict at least a fragment of most genes), their specificity is often low, predicting a large number of false-positive genes in the human genome. Sequence conservation at the protein level with the mouse genome can help eliminate some of those false positives. Here we describe SGP2, a gene prediction program that combines ab initio gene prediction with TBLASTX searches between two genome sequences to provide both sensitive and specific gene predictions. The accuracy of SGP2 when used to predict genes by comparing the human and mouse genomes is assessed on a number of data sets, including single-gene data sets, the highly curated human chromosome 22 predictions, and entire genome predictions from ENSEMBL. Results indicate that SGP2 outperforms purely ab initio gene prediction methods. Results also indicate that SGP2 works about as well with 3x shotgun data as it does with fully assembled genomes. SGP2 provides a high enough specificity that its predictions can be experimentally verified at a reasonable cost. SGP2 was used to generate a complete set of gene predictions on both the human and mouse by comparing the genomes of these two species. Our results suggest that another few thousand human and mouse genes currently not in ENSEMBL are worth verifying experimentally.

Hypothalamus transcriptome profile suggests an anorexia-cachexia syndrome in the anx/anx mouse model

The anx/anx mouse displays poor appetite and lean appearance and is considered a good model for the study of anorexia nervosa. To identify new genes involved in feeding behavior and body weight regulation we performed an expression profiling in the hypothalamus of the anx/anx mice. Using commercial microarrays we detected 156 differentially expressed genes and validated 92 of those using TaqMan low-density arrays. The expression of a set of 87 candidate genes selected based on literature evidences was also quantified by TaqMan low-density arrays. Our results showed enrichment in deregulated genes involved in cell death, cell morphology and cancer as well as an alteration of several signaling circuits involved in energy balance including neuropeptide Y and melanocortin signaling. The expression profile along with the phenotype led us to conclude that anx/anx mice resemble the anorexia-cachexia syndrome typically observed in cancer, infection with human immunodeficiency virus or chronic diseases, rather than starvation, and that anx/anx mice could be considered a good model for the treatment and investigation of this condition.