Weight Gain and Related Comorbidities Following Antiretroviral Initiation in the 2000s: A Systematic Literature Review.

Antiretroviral therapies (ARTs) benefit millions with human immunodeficiency virus. However, concerns about subsequent weight gain and related metabolic complications have emerged. Early ARTs are associated with adipose tissue changes. While newer ARTs may have fewer adipose alterations, it is unclear whether they lead to increased weight gain. A systematic literature review was performed to describe current published literature describing the use of newer ARTs, weight gain, and related comorbidities. Titles and abstracts were screened, focusing on studies that examined ART initiation and subsequent weight gain; publications were then ranked based on publication type, methodology, and comorbidities, emphasizing US studies with large patient cohorts. This yielded a comprehensive review of the 50 publications on weight gain and a range of related comorbidities, including diabetes and hypertension. Most of the studies describing weight gain found the most significant gains during the first year after initiating ART. Overall, patients gained ∼5 kg 18-96 months after initiating ART. Many of the studies reported altered weight-related comorbidities, including increased risk of diabetes and hypertension. Despite an expectation that newer ARTs may be safer, a review of the literature suggests that contemporary ART use is associated with pronounced weight gain and related comorbidities. Future studies should define and quantify the direct role of newer ARTs in weight gain and related comorbidities, as well as clarify the role of specific drug classes in metabolic disturbance, to improve intervention strategies.

Role of Yeasts in the Cranberry Fruit Rot Disease Complex.

Cranberry fruit rot (CFR) is an economically important disease caused by at least 10 species of filamentous fungi. Despite the application of fungicides, incidence of CFR is sometimes high, raising the possibility of a role for microbes other than fungi in the CFR complex. Isolation of microbes from rotten berries on culture media that favor either bacteria or yeasts resulted in mucoid colonies from <15% of dry-harvested rotten berries but up to 60% of wet-harvested berries. The mucoid colonies were identified as yeasts, primarily in the family Saccharomycetaceae. Inoculation of sound berries with three yeasts, Hanseniaspora uvarum, Pichia fermentans, and Pichia terricola, resulted in significantly higher incidence and severity of rot symptoms compared with mock-inoculated controls; these yeasts were recovered from inoculated berries, providing evidence of their pathogenicity. The minimum concentrations of azoxystrobin, chlorothalonil, and prothioconazole that resulted in 80% inhibition of growth compared with untreated controls (MIC80) were determined for a subset of yeasts. In general, MIC80s were higher for azoxystrobin and prothioconazole (usually >64 µg/ml) than for chlorothalonil (usually ≤1 µg/ml). To complement culture-dependent studies, DNA was isolated from wet- and dry-harvested rotten berries, and fungi were identified to the level of family by high-throughput sequencing of the fungal internal transcribed spacer region. There were no fungal families consistently detected among samples by one method (culturing or high-throughput sequencing) and missed by the other that have not previously been reported in cranberry; however, some fungal families were found to be more abundant by one method versus the other. Harvest method (wet or dry) had a significant effect on the composition of fungal communities of rotten berries (P < 0.001), and operational taxonomic units representing the Saccharomycetaceae were more abundant in wet- than dry-harvested berries. Taken together, the results suggest that some yeasts are pathogenic to cranberry and may be especially relevant in wet-harvested berries.

Correction of GSK3ß at young age prevents muscle pathology in mice with myotonic dystrophy type 1.

Myotonic dystrophy type 1 (DM1) is a progressive neuromuscular disease caused by expanded CUG repeats, which misregulate RNA metabolism through several RNA-binding proteins, including CUG-binding protein/CUGBP1 elav-like factor 1 (CUGBP1/CELF1) and muscleblind 1 protein. Mutant CUG repeats elevate CUGBP1 and alter CUGBP1 activity via a glycogen synthase kinase 3ß (GSK3ß)-cyclin D3-cyclin D-dependent kinase 4 (CDK4) signaling pathway. Inhibition of GSK3ß corrects abnormal activity of CUGBP1 in DM1 mice [human skeletal actin mRNA, containing long repeats ( HSALR) model]. Here, we show that the inhibition of GSK3ß in young HSALR mice prevents development of DM1 muscle pathology. Skeletal muscle in 1-yr-old HSALR mice, treated at 1.5 mo for 6 wk with the inhibitors of GSK3, exhibits high fiber density, corrected atrophy, normal fiber size, with reduced central nuclei and normalized grip strength. Because CUG-GSK3ß-cyclin D3-CDK4 converts the active form of CUGBP1 into a form of translational repressor, we examined the contribution of CUGBP1 in myogenesis using Celf1 knockout mice. We found that a loss of CUGBP1 disrupts myogenesis, affecting genes that regulate differentiation and the extracellular matrix. Proteins of those pathways are also misregulated in young HSALR mice and in muscle biopsies of patients with congenital DM1. These findings suggest that the correction of GSK3ß-CUGBP1 pathway in young HSALR mice might have a positive effect on the myogenesis over time.-Wei, C., Stock, L., Valanejad, L., Zalewski, Z. A., Karns, R., Puymirat, J., Nelson, D., Witte, D., Woodgett, J., Timchenko, N. A., Timchenko, L. Correction of GSK3ß at young age prevents muscle pathology in mice with myotonic dystrophy type 1.

Mouse models of the fragile X premutation and fragile X-associated tremor/ataxia syndrome.

Carriers of the fragile X premutation (FPM) have CGG trinucleotide repeat expansions of between 55 and 200 in the 5'-UTR of FMR1, compared to a CGG repeat length of between 5 and 54 for the general population. Carriers were once thought to be without symptoms, but it is now recognized that they can develop a variety of early neurological symptoms as well as being at risk for developing the late onset neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Several mouse models have contributed to our understanding of FPM and FXTAS, and findings from studies using these models are summarized here. This review also discusses how this information is improving our understanding of the molecular and cellular abnormalities that contribute to neurobehavioral features seen in some FPM carriers and in patients with FXTAS. Mouse models show much of the pathology seen in FPM carriers and in individuals with FXTAS, including the presence of elevated levels of Fmr1 mRNA, decreased levels of fragile X mental retardation protein, and ubiquitin-positive intranuclear inclusions. Abnormalities in dendritic spine morphology in several brain regions are associated with neurocognitive deficits in spatial and temporal memory processes, impaired motor performance, and altered anxiety. In vitro studies have identified altered dendritic and synaptic architecture associated with abnormal Ca(2+) dynamics and electrical network activity. FPM mice have been particularly useful in understanding the roles of Fmr1 mRNA, fragile X mental retardation protein, and translation of a potentially toxic polyglycine peptide in pathology. Finally, the potential for using these and emerging mouse models for preclinical development of therapies to improve neurological function in FXTAS is considered.

Genome-wide alteration of 5-hydroxymethylcytosine in a mouse model of fragile X-associated tremor/ataxia syndrome.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder in which patients carry premutation alleles of 55-200 CGG repeats in the FMR1 gene. To date, whether alterations in epigenetic regulation modulate FXTAS has gone unexplored. 5-Hydroxymethylcytosine (5hmC) converted from 5-methylcytosine (5mC) by the ten-eleven translocation (TET) family of proteins has been found recently to play key roles in neuronal functions. Here, we undertook genome-wide profiling of cerebellar 5hmC in a FXTAS mouse model (rCGG mice) and found that rCGG mice at 16 weeks showed overall reduced 5hmC levels genome-wide compared with age-matched wild-type littermates. However, we also observed gain-of-5hmC regions in repetitive elements, as well as in cerebellum-specific enhancers, but not in general enhancers. Genomic annotation and motif prediction of wild-type- and rCGG-specific differential 5-hydroxymethylated regions (DhMRs) revealed their high correlation with genes and transcription factors that are important in neuronal developmental and functional pathways. DhMR-associated genes partially overlapped with genes that were differentially associated with ribosomes in CGG mice identified by bacTRAP ribosomal profiling. Taken together, our data strongly indicate a functional role for 5hmC-mediated epigenetic modulation in the etiology of FXTAS, possibly through the regulation of transcription.

Design factors that influence PCR amplification success of cross-species primers among 1147 mammalian primer pairs.

BACKGROUND: Cross-species primers have been used with moderate success to address a variety of questions concerning genome structure, evolution, and gene function. However, the factors affecting their success have never been adequately addressed, particularly with respect to producing a consistent method to achieve high throughput. Using 1,147 mammalian cross-species primer pairs (1089 not previously reported), we tested several factors to determine their influence on the probability that a given target will amplify in a given species under a single amplification condition. These factors included: number of mismatches between the two species (the index species) used to identify conserved regions to which the primers were designed, GC-content of the gene and amplified region, CpG dinucleotides in the primer region, degree of encoded protein conservation, length of the primers, and the degree of evolutionary distance between the target species and the two index species. RESULTS: The amplification success rate for the cross-species primers was significantly influenced by the number of mismatches between the two index species (6-8% decrease per mismatch in a primer pair), the GC-content within the amplified region (for the dog, GC > or = 50%, 56.9% amplified; GC<50%, 74.2% amplified), the degree of protein conservation (R2 = 0.14) and the relatedness of the target species to the index species. For the dog, 598 products of 930 primer pairs (64.3%) (excluding primers in which dog was an index species) were sequenced and shown to be the expected product, with an additional three percent producing the incorrect sequence. When hamster DNA was used with the single amplification condition in a microtiter plate-based format, 510 of 1087 primer pairs (46.9%) produced amplified products. The primer pairs are spaced at an average distance of 2.3 Mb in the human genome and may be used to produce up to several hundred thousand bp of species-specific sequence. CONCLUSION: The most important factors influencing the proportion of successful amplifications are the number of index species mismatches, GC-richness of the target amplimer, and the relatedness of the target species to the index species, at least under the single PCR condition used. The 1147 cross-species primer pairs can be used in a high throughput manner to generate data for studies on the genetics and genomics of non-sequenced mammalian genomes.