Echocardiographic characterization of age- and sex-associated differences in cardiac function and morphometry in nonhuman primates.

Aging per se is a major risk factor for cardiovascular diseases and is associated with progressive changes in cardiac structure and function. Rodent models are commonly used to study cardiac aging, but do not closely mirror differences as they occur in humans. Therefore, we performed a 2D echocardiographic study in non-human primates (NHP) to establish age- and sex-associated differences in cardiac function and morphometry in this animal model.

Parental genetic contributions to neonatal temperament in a nonhuman primate (Macaca mulatta) model.

Temperament is an individual's nature and is widely believed to have a heritable foundation. Few studies, however, have evaluated paternal and maternal contributions to the triadic dimensions of temperament. Rhesus monkeys are widely utilized to model genetic contributions to human development due to their close genetic-relatedness and common temperament structure, providing a powerful translational model for investigating paternal and maternal genetic influences on temperament.

Multi-group multi-time point confirmatory factor analysis of the triadic structure of temperament: A nonhuman primate model.

Attempts to describe the latent structure of human infant temperament have led some to suggest the existence of three major dimensions. An earlier exploratory factor analysis (EFA) supported a triadic structure of temperament in week-old rhesus monkey infants, paralleling the structure in human infants. This study sought to confirm the latent triadic structure of temperament across the first month of life in a larger sample of rhesus monkey infants (N = 668), reared by their mothers or in a neonatal nursery.

Increased Drp1 Acetylation by Lipid Overload Induces Cardiomyocyte Death and Heart Dysfunction.

Rationale: Lipid overload-induced heart dysfunction is characterized by cardiomyocyte death, myocardial remodeling, and compromised contractility, but the impact of excessive lipid supply on cardiac function remains poorly understood.

Objective: To investigate the regulation and function of the mitochondrial fission protein Drp1 (dynamin-related protein 1) in lipid overload-induced cardiomyocyte death and heart dysfunction.

Methods And Results: Mice fed a high-fat diet (HFD) developed signs of obesity and type II diabetes mellitus, including hyperlipidemia, hyperglycemia, hyperinsulinemia, and hypertension.

Effects of Reducing Norepinephrine Levels via DSP4 Treatment on Amyloid-β Pathology in Female Rhesus Macaques (Macaca Mulatta).

The degeneration in the locus coeruleus associated with Alzheimer's disease suggests an involvement of the noradrenergic system in the disease pathogenesis. The role of depleted norepinephrine was tested in adult and aged rhesus macaques to develop a potential model for testing Alzheimer's disease interventions. Monkeys were injected with the noradrenergic neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) or vehicle at 0, 3, and 6 months; brains were harvested at 9 months.

Low Inherent Sensitivity to the Intoxicating Effects of Ethanol in Rhesus Monkeys with Low CSF Concentrations of the Serotonin Metabolite 5-Hydroxyindoleacetic Acid.

Background: Type 2 alcoholism is characterized by low serotonin system functioning and has a high degree of heritability, with offspring of alcoholics often showing a reduced response to the intoxicating effects of ethanol (EtOH), which is thought to be marker for future alcohol use disorders (AUDs). As such, an important aim of studies investigating the origins of AUDs is to understand the relationship between serotonin system functioning and level of intoxication. A nonhuman primate model was used to evaluate observational ratings of sensitivity to EtOH and to further investigate the relationship between central serotonin activity and behavioral response to EtOH.

Intermittent Access to Ethanol Induces Escalated Alcohol Consumption in Primates.

Background: Escalation of voluntary alcohol drinking is characteristic of alcohol addiction and can be induced in rodents using intermittent access to alcohol. This model has been used to evaluate candidate therapeutics, but key systems involved in the transition into alcohol addiction, such as CRF, differ in their organization between rodents and primates. We examined the ability of an intermittent access schedule to induce escalation of voluntary alcohol drinking in non-human primates and used this model to assess the role of corticotropin releasing hormone (CRF) signaling in this process.

An overview of nonhuman primates in aging research.

A graying human population and the rising costs of healthcare have fueled the growing need for a sophisticated translational model of aging. Nonhuman primates (NHPs) experience aging processes similar to humans and, as a result, provide an excellent opportunity to study a closely related species. Rhesus monkeys share >92% homology and are the most commonly studied NHP.

Mitochondrial compromise in 3-year old patas monkeys exposed in utero to human-equivalent antiretroviral therapies.

Antiretroviral (ARV) drug therapy, given during pregnancy for prevention of mother-to-child transmission of human immunodeficiency virus 1 (HIV-1), induces fetal mitochondrial dysfunction in some children. However, the persistence/reversibility of that dysfunction is unclear. Here we have followed Erythrocebus patas (patas) monkey offspring for up to 3 years of age (similar in development to a 15-year old human) after exposure of the dams to human-equivalent in utero ARV exposure protocols.

Rhesus macaques (Macaca mulatta) with self-injurious behavior show less behavioral anxiety during the human intruder test.

Self-injurious behavior (SIB) has been linked to anxiety in the human literature, but relatively few studies have explored this link in rhesus macaques. A widely used behavioral assessment of anxiety, the human intruder test (HIT), employs the mildly stressful stimulus of an unfamiliar experimenter to assess anxious behavior in macaques. The HIT was conducted on 59 (20 male) laboratory housed rhesus macaques, 30 with a record of SIB (10 male).

Resveratrol prevents high fat/sucrose diet-induced central arterial wall inflammation and stiffening in nonhuman primates.

Central arterial wall stiffening, driven by a chronic inflammatory milieu, accompanies arterial diseases, the leading cause of cardiovascular (CV) morbidity and mortality in Western society. An increase in central arterial wall stiffening, measured as an increase in aortic pulse wave velocity (PWV), is a major risk factor for clinical CV disease events. However, no specific therapies to reduce PWV are presently available.

The influence of age on serum concentrations of cardiac troponin I: results in rats, monkeys, and commercial sera.

Cardiac troponins serve as serum biomarkers of myocardial injury. The current study examined the influence of age on serum concentrations of cardiac troponin I (cTnI). An ultrasensitive immunoassay was used to monitor cTnI concentrations in Sprague-Dawley (SD) rats and Erythrocebus patas monkeys of different ages.

Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study.

Calorie restriction (CR), a reduction of 10–40% in intake of a nutritious diet, is often reported as the most robust non-genetic mechanism to extend lifespan and healthspan. CR is frequently used as a tool to understand mechanisms behind ageing and age-associated diseases. In addition to and independently of increasing lifespan, CR has been reported to delay or prevent the occurrence of many chronic diseases in a variety of animals.

Delayed imitation of lipsmacking gestures by infant rhesus macaques (Macaca mulatta).

Human infants are capable of accurately matching facial gestures of an experimenter within a few hours after birth, a phenomenon called neonatal imitation. Recent studies have suggested that rather than being a simple reflexive-like behavior, infants exert active control over imitative responses and 'provoke' previously imitated gestures even after a delay of up to 24 h. Delayed imitation is regarded as the hallmark of a sophisticated capacity to control and flexibly engage in affective communication and has been described as an indicator of innate protoconversational readiness.

Visual discrimination of male and female faces by infant rhesus macaques.

Recent studies have revealed that human infants process female faces differently from male faces. To test whether a similar preference for female faces exists in other primates, we presented nursery-reared infant rhesus macaques with photographs of macaque faces and human faces. At <1 month old, infant macaques preferentially oriented towards female macaque faces when faces were presented upright.

Sex differences in play behavior in juvenile tufted capuchin monkeys (Cebus apella).

According to the motor training hypothesis, play behavior in juvenile primates improves motor skills that are required in later adult life. Sex differences in juvenile play behavior can therefore be expected when adult animals assume distinct sexually dimorphic roles. Tufted capuchin monkeys show sexually dimorphic levels of physical antagonism in both inter- and intra-group encounters.

The effects of fur rubbing on the social behavior of tufted capuchin monkeys.

Fur rubbing has often been attributed as a social as well as a medicinal function in capuchin monkeys, yet to date there have been no studies investigating the effects of fur rubbing on subsequent group dynamics. Here, we report for the first time how social group cohesion is affected by fur rubbing in tufted capuchin monkeys. Fifteen captive capuchins were each observed six times for 45 min, three times following the provision of materials typically used for fur rubbing (onion) and three times following control food items (apple).

Rapid tolerance and locomotor sensitization in ethanol-naïve adolescent rhesus macaques.

Background: Acute and chronic tolerance, as well as locomotor sensitization, have been linked to ethanol intake. This study examined the change in response between 2 acutely administered doses of ethanol in adolescent rhesus macaques, with the objective of investigating rapid tolerance and locomotor sensitization to the behavioral effects of ethanol, and whether these phenomena are related to voluntary ethanol consumption in nonhuman primates.

Methods: Rhesus macaques (n = 109, 42 males, 67 females) were administered 2 sequential intravenous doses of ethanol (2.

Use of animal-operated folding perches by rhesus macaques (Macaca mulatta).

Providing captive or laboratory animals with the best possible living conditions has led to many ideas about how caging environments can be enhanced and the animals' lives can be enriched. This study focused primarily on 2 issues: more efficient use of existing caging and providing animals with a measure of control over their environments. We designed a new springloaded folding perching apparatus that, when modified for size, could be added to almost any caging system.

Endometriosis: clinical monitoring and treatment procedures in Rhesus Monkeys.

The National Institute on Aging (NIA) sponsored a workshop on September 8, 2004, to discuss the incidence, diagnosis, and clinical treatment of endometriosis in rhesus monkey colonies. Because of the growing number of aging studies using rhesus monkeys, this disease has become more prevalent as monkeys are living into advanced ages in captivity. The objective of the workshop was to gather information from various NIA-supported aging rhesus colonies on the incidence, clinical manifestations, indicators for early detection, and possible treatment options for endometriosis.

Association between the recombinant human serotonin transporter linked promoter region polymorphism and behavior in rhesus macaques during a separation paradigm.

Human studies have suggested an association between a variable length polymorphism in the serotonin transporter gene promoter region and vulnerability to anxiety and depression. Relative to the long (l) allele, the short (s) allele increases the risk of developing depression in individuals exposed to stressful life events. An orthologue of the human variant is present in rhesus macaques and allows for studies in animals exposed to stress.

Age-dependent variation in behavior following acute ethanol administration in male and female adolescent rhesus macaques (Macaca mulatta).

Background: There has been considerable focus on the adolescent stage of development in the study of alcohol use and the etiology of alcohol-related problems. Because adolescence is a process of dynamic change rather than a discrete or static stage of development, it is important to consider ontogenetic changes in the response to ethanol within the adolescent time period. In rodents, levels of ethanol-induced motor impairment have been shown to increase from early to late adolescence.

Early predictors of self-biting in socially-housed rhesus macaques (Macaca mulatta).

The development of self-biting behavior in captive monkeys is little understood and poses a serious risk to their well-being. Although early rearing conditions may influence the expression of this behavior, not all animals reared under similar conditions self-bite. The purpose of this study was to examine the effects of three rearing conditions on biting behavior and to determine whether early infant behavior can predict later self-biting.