Project description:ObjectivesEpigenetic mechanisms influence the development and maintenance of complex phenotypes and may also contribute to the evolution of species-specific phenotypes. With respect to skeletal traits, little is known about the gene regulation underlying these hard tissues or how tissue-specific patterns are associated with bone morphology or vary among species. To begin exploring these topics, this study evaluates one epigenetic mechanism, DNA methylation, in skeletal tissues from five nonhuman primate species which display anatomical and locomotor differences representative of their phylogenetic groups.Materials and methodsFirst, we test whether intraspecific variation in skeletal DNA methylation is associated with intraspecific variation in femur morphology. Second, we identify interspecific differences in DNA methylation and assess whether these lineage-specific patterns may have contributed to species-specific morphologies. Specifically, we use the Illumina Infinium MethylationEPIC BeadChip to identify DNA methylation patterns in femur trabecular bone from baboons (n = 28), macaques (n = 10), vervets (n = 10), chimpanzees (n = 4), and marmosets (n = 6).ResultsSignificant differentially methylated positions (DMPs) were associated with a subset of morphological variants, but these likely have small biological effects and may be confounded by other variables associated with morphological variation. Conversely, several species-specific DMPs were identified, and these are found in genes enriched for functions associated with complex skeletal traits.DiscussionOverall, these findings reveal that while intraspecific epigenetic variation is not readily associated with skeletal morphology differences, some interspecific epigenetic differences in skeletal tissues exist and may contribute to evolutionarily distinct phenotypes. This work forms a foundation for future explorations of gene regulation and skeletal trait evolution in primates.
Project description:The aim of this study was to characterize the genome-wide DNA methylation profiles of nonhuman primate trabecular bone samples (n=58), identify how they relate to aspects of femur bone morphology, and assess how these epigenetic patterns vary between taxa. The Illumina Infinium MethylationEPIC array was used to assess genome-wide methylation patterns.
Project description:Uterine stretch is thought to induce preterm labor in women with twin and higher order pregnancies, but the pathophysiology remains unclear. We investigated the pathogenesis of stretch-induced preterm birth for the first time in a pregnant nonhuman primate model. Eleven chronically catheterized pregnant monkeys (Macaca nemestrina) at 118-125 days gestation (term=172 days) received either: 1) inflation of intra-amniotic balloons (N=6) or 2) saline inoculation (N=5). Cesarean section and fetal necropsy was performed due to preterm labor or to collect tissues, except in one case where the animal delivered spontaneously, reducing samples for microarray analysis to ten (five stretch and five control animals). Amniotic fluid and maternal plasma were analyzed for multiple cytokines and prostaglandins using Luminex, enzyme-linked immunosorbent assay and Analysis of Covariance. Ribonucleic acid was extracted from the myometrium in the lower uterus at Cesarean section and analyzed by microarray and quantitative reverse transcriptase polymerase chain reaction.
Project description:Uterine stretch is thought to induce preterm labor in women with twin and higher order pregnancies, but the pathophysiology remains unclear. We investigated the pathogenesis of stretch-induced preterm birth for the first time in a pregnant nonhuman primate model.
Project description:Viruses resembling human TT virus (TTV) were searched for in sera from nonhuman primates by PCR with primers deduced from well-conserved areas in the untranslated region. TTV DNA was detected in 102 (98%) of 104 chimpanzees, 9 (90%) of 10 Japanese macaques, 4 (100%) of 4 red-bellied tamarins, 5 (83%) of 6 cotton-top tamarins, and 5 (100%) of 5 douroucoulis tested. Analysis of the amplification products of 90 to 106 nucleotides revealed TTV DNA sequences specific for each species, with a decreasing similarity to human TTV in the order of chimpanzee, Japanese macaque, and tamarin/douroucouli TTVs. Full-length viral sequences were amplified by PCR with inverted nested primers deduced from the untranslated region of TTV DNA from each species. All animal TTVs were found to be circular with a genomic length at 3.5 to 3.8 kb, which was comparable to or slightly shorter than human TTV. Sequences closely similar to human TTV were determined by PCR with primers deduced from a coding region (N22 region) and were detected in 49 (47%) of the 104 chimpanzees; they were not found in any animals of the other species. Sequence analysis of the N22 region (222 to 225 nucleotides) of chimpanzee TTV DNAs disclosed four genetic groups that differed by 36.1 to 50.2% from one another; they were 35.0 to 52.8% divergent from any of the 16 genotypes of human TTV. Of the 104 chimpanzees, only 1 was viremic with human TTV of genotype 1a. It was among the 53 chimpanzees which had been used in transmission experiments with human hepatitis viruses. Antibody to TTV of genotype 1a was detected significantly more frequently in the chimpanzees that had been used in transmission experiments than in those that had not (8 of 28 [29%] and 3 of 35 [9%], respectively; P = 0.038). These results indicate that species-specific TTVs are prevalent in nonhuman primates and that human TTV can cross-infect chimpanzees.
Project description:The network organization of the human brain varies across individuals, changes with development and aging, and differs in disease. Discovering the major dimensions along which this variability is displayed remains a central goal of both neuroscience and clinical medicine. Such efforts can be usefully framed within the context of the brain's modular network organization, which can be assessed quantitatively using computational techniques and extended for the purposes of multi-scale analysis, dimensionality reduction, and biomarker generation. Although the concept of modularity and its utility in describing brain network organization is clear, principled methods for comparing multi-scale communities across individuals and time are surprisingly lacking. Here, we present a method that uses multi-layer networks to simultaneously discover the modular structure of many subjects at once. This method builds upon the well-known multi-layer modularity maximization technique, and provides a viable and principled tool for studying differences in network communities across individuals and within individuals across time. We test this method on two datasets and identify consistent patterns of inter-subject community variability, demonstrating that this variability - which would be undetectable using past approaches - is associated with measures of cognitive performance. In general, the multi-layer, multi-subject framework proposed here represents an advance over current approaches by straighforwardly mapping community assignments across subjects and holds promise for future investigations of inter-subject community variation in clinical populations or as a result of task constraints.
Project description:The identification of the most efficient method for whole central nervous system targeting that is translatable to humans and the safest route of adeno-associated virus (AAV) administration is a major concern for future applications in clinics. Additionally, as many AAV serotypes were identified for gene introduction into the brain and the spinal cord, another key to human gene-therapy success is to determine the most efficient serotype. In this study, we compared lumbar intrathecal administration through catheter implantation and intracerebroventricular administration in the cynomolgus macaque. We also evaluated and compared two AAV serotypes that are currently used in clinical trials: AAV9 and AAVrh10. We demonstrated that AAV9 lumbar intrathecal delivery using a catheter achieved consistent transgene expression in the motor neurons of the spinal cord and in the neurons/glial cells of several brain regions, whereas AAV9 intracerebroventricular delivery led to a consistent transgene expression in the brain. In contrast, AAVrh10 lumbar intrathecal delivery led to rare motor neuron targeting. Finally, we found that AAV9 efficiently targets respiratory and skeletal muscles after injection into the cerebrospinal fluid (CSF), which represents an outstanding new property that can be useful for the treatment of diseases affecting both the central nervous system and muscle.
Project description:BACKGROUND:Because prostate specific antigen (PSA) is released at increased levels into the blood early in the development of prostate cancer, benign prostatic hyperplasia (BPH) and prostatitis, it is widely used as a marker for these diseases. However, PSA has clinical limitations as a screen for prostatic diseases due to its low sensitivity and specificity. There is a strong need to better understand the biology of PSA and factors affecting its serum levels. METHODS:We evaluated cynomolgus macaques, rhesus macaques, baboons, and marmosets for their suitability as models for the study of PSA biology and prostatic diseases. RESULTS:Prostates of several nonhuman primates are anatomically similar to the human counterpart. Anti-human PSA antibody detected PSA antigens in all the Old World monkeys (cynomolgus macaques, rhesus macaques, and baboons) but not in marmosets. Of the Old World monkeys, cynomolgus macaques have the highest serum PSA levels; baboons have the lowest. Serum PSA levels from macaques includes a number of outlier samples with unusually high values. We also report two cases of abnormal pathologies in macaques accompanied by high serum PSA levels. One case consisted of prostatic hyperplasia involving both glandular and basal cells in a cynomolgus macaque and another of glandular hyperplasia and atrophy in a rhesus macaque. The finding that pathological changes in the prostate of macaques may lead to increases in serum PSA is worthy of further exploration. CONCLUSION:Cynomolgus macaques and rhesus macaques are promising animal models for PSA biology studies.
Project description:Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the United States. Human epidemiological studies provide challenges for understanding mechanisms that regulate initiation and progression of CVD due to variation in lifestyle, diet, and other environmental factors. Studies describing metabolic and physiologic aspects of CVD, and those investigating genetic and epigenetic mechanisms influencing CVD initiation and progression, have been conducted in multiple Old World nonhuman primate (NHP) species. Major advantages of NHPs as models for understanding CVD are their genetic, metabolic, and physiologic similarities with humans, and the ability to control diet, environment, and breeding. These NHP species are also genetically and phenotypically heterogeneous, providing opportunities to study gene by environment interactions that are not feasible in inbred animal models. Each Old World NHP species included in this review brings unique strengths as models to better understand human CVD. All develop CVD without genetic manipulation providing multiple models to discover genetic variants that influence CVD risk. In addition, as each of these NHP species age, their age-related comorbidities such as dyslipidemia and diabetes are accelerated proportionally 3 to 4 times faster than in humans.In this review, we discuss current CVD-related research in NHPs focusing on selected aspects of CVD for which nonprimate model organism studies have left gaps in our understanding of human disease. We include studies on current knowledge of genetics, epigenetics, calorie restriction, maternal calorie restriction and offspring health, maternal obesity and offspring health, nonalcoholic steatohepatitis and steatosis, Chagas disease, microbiome, stem cells, and prevention of CVD.