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Purpose: PET imaging using [ 11 C]metoclopramide revealed the importance of P-glycoprotein (P-gp, ABCB1) in mediating the brain-to-blood efflux of substrates across the blood-brain barrier (BBB). In this work, the elimination rate constant from the brain (k E,brain ), calculated from dynamic PET images without the need for arterial blood sampling, was evaluated as an outcome parameter for the interpretation of [ 11 C]metoclopramide PET data., Procedures: k E,brain parameter was obtained by linear regression of log-transformed brain time-activity curves (TACs). k E,brain values (h -1 ) obtained under baseline conditions were compared with values obtained after complete P-gp inhibition using tariquidar in rats (n = 4) and baboons (n = 4) or after partial inhibition using cyclosporine A in humans (n = 10). In baboons, the sensitivity of k E,brain to measure complete P-gp inhibition was compared with outcome parameters derived from kinetic modeling using a 1-tissue compartment model (1-TCM). Finally, k E,brain -maps were generated in each species using PMOD software., Results: The linear part of the log-transformed brain TACs occurred from 10 to 30 min after radiotracer injection in rats, from 15 to 60 min in baboons, and from 20 to 60 min in humans. P-gp inhibition significantly decreased k E,brain values by 39 ± 12% in rats (p < 0.01), by 32 ± 6% in baboons (p < 0.001), and by 37 ± 22% in humans (p < 0.001). In baboons, P-gp inhibition consistently decreased the brain-to-plasma efflux rate constant k 2 (36 ± 9%, p < 0.01) leading to an increase in the total brain volume of distribution (V T , 101 ± 12%, p < 0.001). In all studied species, brain k E,brain -maps displayed decreased P-gp-mediated efflux across the BBB., Conclusions: k E,brain of [ 11 C]metoclopramide provides a simple outcome parameter to describe P-gp function in the living brain when arterial input function data are unavailable, although less sensitive than V T . k E,brain -maps represent easy to compute parametric images reflecting the effect of P-gp on [ 11 C]metoclopramide elimination from the brain., (© 2023. The Author(s), under exclusive licence to World Molecular Imaging Society.)

MicroRNAs (miRs) play an important role in the pathophysiology of endometriosis; however, the role of miR-210 in endometriosis remains unclear. This study explores the role of miR-210 and its targets, IGFBP3 and COL8A1, in ectopic lesion growth and development. Matched eutopic (EuE) and ectopic (EcE) endometrial samples were obtained for analysis from baboons and women with endometriosis. Immortalized human ectopic endometriotic epithelial cells (12Z cells) were utilized for functional assays. Endometriosis was experimentally induced in female baboons (n = 5). Human matched endometrial and endometriotic tissues were obtained from women (n = 9, 18-45 years old) with regular menstrual cycles. Quantitative reverse transcript polymerase chain reaction (RT-qPCR) analysis was performed for in vivo characterization of miR-210, IGFBP3, and COL8A1. In situ hybridization and immunohistochemical analysis were performed for cell-specific localization. Immortalized endometriotic epithelial cell lines (12Z) were utilized for in vitro functional assays. MiR-210 expression was decreased in EcE, while IGFBP3 and COL8A1 expression was increased in EcE. MiR-210 was expressed in the glandular epithelium of EuE but attenuated in those of EcE. IGFBP3 and COL8A1 were expressed in the glandular epithelium of EuE and were increased compared to EcE. MiR-210 overexpression in 12Z cells suppressed IGFBP3 expression and attenuated cell proliferation and migration. MiR-210 repression and subsequent unopposed IGFBP3 expression may contribute to endometriotic lesion development by increasing cell proliferation and migration., (© 2023. The Author(s).)

The beta-site amyloid precursor protein cleaving enzyme (BACE1) is responsible for initiating the generation of beta-amyloid, the major constituent of amyloid plaques in Alzheimer's disease (AD). The purpose of this study was to develop a specific BACE1 radioligand for visualization of the distribution pattern and quantification of the BACE1 protein in the rodent and monkey brain both in vitro by autoradiography and in vivo by positron emission tomography (PET). The BACE1 inhibitor RO6807936 originating from an in-house chemical drug optimization program was selected based on its PET tracer-like physicochemical properties and a favorable pharmacokinetic profile. Saturation binding analysis of [ 3 H]RO6807936 revealed specific and high-affinity binding (K D  = 2.9 nM) and a low B max value (4.3 nM) of the BACE1 protein in native rat brain membranes. [ 3 H]RO6807936 binding showed a ubiquitous distribution on rat brain slices in vitro with higher levels in the CA3 pyramidal cell layer and the granule cell layer of the hippocampus. In a next step, RO6807936 was successfully radiolabeled with carbon-11 and showed acceptable uptake in the baboon brain as well as a widespread and rather homogeneous distribution consistent with rodent data. In vivo blockade studies with a specific BACE1 inhibitor reduced uptake of the tracer to homogenous levels across brain regions and demonstrated specificity of the signal. Our data warrant further profiling of this PET tracer candidate in humans to investigate BACE1 expression in normal individuals and those with AD and as an imaging biomarker for target occupancy studies in clinical drug trials., (© 2023 John Wiley & Sons Ltd.)

Primary human mammary epithelial cells (pHMECs) are known to be remarkably difficult to engineer genetically. Here, we present a protocol for efficient transduction of pHMECs using a baboon retroviral envelope glycoprotein for pseudotyping of lentiviral vectors (BaEV-LVs). We describe the preparation of the BaEV-LVs, the isolation of pHMECs from breast samples, and the subsequent transduction of pHMECs. We also detail the use of CRISPRi technology to efficiently silence gene expression in pHMECs, which can then be used for functional assays. For complete details on the use and execution of this protocol, please refer to Richart et al. (2022). 1 ., Competing Interests: Declaration of interests E.V. is the inventor of the patent on pseudotyping of retroviral particles with BaEV envelope glycoproteins (patent WO 07290918.7)., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

After pig-to-baboon kidney transplantation, episodes of hypovolemia and hypotension from an unexplained mechanism have been reported. This study evaluated the renin-angiotensin-aldosterone system post-kidney xenotransplantation. Kidneys from genetically-engineered pigs were transplanted into 5 immunosuppressed baboons after the excision of the native kidneys. Immunosuppressive therapy was based on the blockade of the CD40/CD154 costimulation pathway. Plasma renin, angiotensinogen (AGT), angiotensin II (Ang II), aldosterone levels, and urine osmolality and electrolytes were measured in healthy pigs, healthy nonimmunosuppressed baboons, and immunosuppressed baboons with life-supporting pig kidney grafts. After pig kidney transplantation, plasma renin and Ang II levels were not significantly different, although Ang II trended lower, even though plasma AGT and potassium were increased. Plasma aldosterone levels were unchanged. Urine osmolality and sodium concentration were decreased. Even in the presence of increasing AGT and potassium levels, lower plasma Ang II concentrations may be because of reduced, albeit not absent, the reactivity of pig renin to cleave baboon AGT, suggesting an impaired response of the renin-angiotensin-aldosterone system to hypovolemic and hypotensive episodes. The maintenance of aldosterone may be protective. The reduced urine osmolality and sodium concentration reflect the decreased ability of the pig kidney to concentrate urine. These considerations should not prohibit successful clinical pig kidney xenotransplantation., (Copyright © 2022 American Society of Transplantation & American Society of Transplant Surgeons. All rights reserved.)

Kidney xenotransplantation is expected to contribute to resolving the shortage of kidneys from deceased human donors. Although progress in experimental life-supporting pig renal xenotransplantation has been encouraging, there are still issues to be considered before a clinical trial can be initiated. We attempted to clarify some of these by an in vitro study. Blood was drawn from healthy volunteers (Volunteers, n=20), patients with end-stage renal disease (ESRD, n=20) pre-operation (Pre), and on Day 1 (POD 1) and Day 14 (POD 14) after renal allotransplantation, brain-dead organ donors (DBD, n=20), and renal allotransplant recipients who were currently experiencing T cell-mediated rejection (Allo-TCMR, n=20). Serum IgM/IgG binding to, and complement-dependent cytotoxicity (CDC) of, PBMCs and RBCs from (a) wild-type (WT), (b) α1,3-galactosyltransferase gene-knockout (GTKO), (c) GTKO/beta-1,4-N-acety1 galactosaminyltransferase 2-knockout (GTKO/β4GalNT2KO), (d) GTKO/cytidine monophosphate-N-acetylneuraminic acid hydroxylase-knockout (GTKO/CMAHKO), and (e) GTKO/β4GalNT2KO/CMAHKO/hCD55 (TKO/hCD55) pigs were measured by flow cytometry. We obtained the following results: (i) Serum IgM/IgG binding and CDC in Volunteers were significantly greater to WT, GTKO, and GTKO/β4GalNT2KO PBMCs or RBCs than to GTKO/CMAHKO and TKO/hCD55 cells; (ii) ESRD, DBD, and Allo-TCMR serum antibody binding and CDC to WT pig PBMCs were significantly greater than to GTKO, GTKO/β4GalNT2KO, GTKO/CMAHKO, and TKO/hCD55 cells; (iii) antibody binding to GTKO/CMAHKO pig cells was significantly lower in hemodialysis than peritoneal dialysis patients. (iv) Two of twenty allotransplantation recipients' serum IgG binding to GTKO pig PBMCs increased on POD14 compared with Pre, but IgG binding to GTKO pig RBCs did not; (v) In all sera, the lowest antibody binding and CDC were to GTKO/CMAHKO and TKO/CD55 pig cells. We conclude (i) CMAHKO in the pig may be critical to the success of clinical pig kidney xenotransplantation, and may be the most important after GTKO, at least in Chinese patients; (ii) subjects with ESRD, or who are immunosuppressed after kidney allotransplantation, and DBD, have lower levels of antibody binding and CDC to genetically-engineered pig cells than do volunteers; (iii) TKO pigs with selected human 'protective' transgenes, e.g., CD55, are likely to prove to be the optimal sources of kidneys for clinical xenotransplantation., Competing Interests: Author JD is employed by Chengdu Clonorgan Biotechnology Co., LTD. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Li, Feng, Du, Xia, Cooper, Jiang, He, Pan, Chen and Wang.)

The King Baboon spider, Pelinobius muticus , is a burrowing African tarantula. Its impressive size and appealing coloration are tempered by reports describing severe localized pain, swelling, itchiness, and muscle cramping after accidental envenomation. Hyperalgesia is the most prominent symptom after bites from P. muticus , but the molecular basis by which the venom induces pain is unknown. Proteotranscriptomic analysis of P. muticus venom uncovered a cysteine-rich peptide, δ/κ-theraphotoxin-Pm1a (δ/κ-TRTX-Pm1a), that elicited nocifensive behavior when injected into mice. In small dorsal root ganglion neurons, synthetic δ/κ-TRTX-Pm1a (sPm1a) induced hyperexcitability by enhancing tetrodotoxin-resistant sodium currents, impairing repolarization and lowering the threshold of action potential firing, consistent with the severe pain associated with envenomation. The molecular mechanism of nociceptor sensitization by sPm1a involves multimodal actions over several ion channel targets, including Na V 1.8, K V 2.1, and tetrodotoxin-sensitive Na V channels. The promiscuous targeting of peptides like δ/κ-TRTX-Pm1a may be an evolutionary adaptation in pain-inducing defensive venoms., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)

In the mouse, the osteoblast-derived hormone Lipocalin-2 (LCN2) suppresses food intake and acts as a satiety signal. We show here that meal challenges increase serum LCN2 levels in persons with normal or overweight, but not in individuals with obesity. Postprandial LCN2 serum levels correlate inversely with hunger sensation in challenged subjects. We further show through brain PET scans of monkeys injected with radiolabeled recombinant human LCN2 (rh-LCN2) and autoradiography in baboon, macaque, and human brain sections, that LCN2 crosses the blood-brain barrier and localizes to the hypothalamus in primates. In addition, daily treatment of lean monkeys with rh-LCN2 decreases food intake by 21%, without overt side effects. These studies demonstrate the biology of LCN2 as a satiety factor and indicator and anorexigenic signal in primates. Failure to stimulate postprandial LCN2 in individuals with obesity may contribute to metabolic dysregulation, suggesting that LCN2 may be a novel target for obesity treatment., Competing Interests: PP, IM, SS, LH, KP, BB, NL, FB, JK, PC, FZ, NS, MB, SK, LS, MU, CM, KS, MJ, CC, SS, BL, AM, JM, MR, SK No competing interests declared, (© 2020, Petropoulou et al.)

In vertebrates, glucocorticoid secretion occurs in response to energetic and psychosocial stressors that trigger the hypothalamic-pituitary-adrenal (HPA) axis. Measuring glucocorticoid concentrations can therefore shed light on the stressors associated with different social and environmental variables, including dominance rank. Using 14,172 fecal samples from 237 wild female baboons, we test the hypothesis that high-ranking females experience fewer psychosocial and/or energetic stressors than lower-ranking females. We predicted that high-ranking females would have lower fecal glucocorticoid (fGC) concentrations than low-ranking females. Because dominance rank can be measured in multiple ways, we employ an information theoretic approach to compare 5 different measures of rank as predictors of fGC concentrations: ordinal rank; proportional rank; Elo rating; and two approaches to categorical ranking (alpha vs non-alpha and high-middle-low). Our hypothesis was supported, but it was also too simplistic. We found that alpha females exhibited substantially lower fGCs than other females (typical reduction = 8.2%). If we used proportional rank instead of alpha versus non-alpha status in the model, we observed a weak effect of rank such that fGCs rose 4.2% from the highest- to lowest-ranking female in the hierarchy. Models using ordinal rank, Elo rating, or high-middle-low categories alone failed to explain variation in female fGCs. Our findings shed new light on the association between dominance rank and the stress response, the competitive landscape of female baboons as compared to males, and the assumptions inherent in a researcher's choice of rank metric., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In humans and other animals, harsh conditions in early life can have profound effects on adult physiology, including the stress response. This relationship may be mediated by a lack of supportive relationships in adulthood. That is, early life adversity may inhibit the formation of supportive social ties, and weak social support is itself often linked to dysregulated stress responses. Here, we use prospective, longitudinal data from wild baboons in Kenya to test the links between early adversity, adult social bonds, and adult fecal glucocorticoid hormone concentrations (a measure of hypothalamic-pituitary-adrenal [HPA] axis activation and the stress response). Using a causal inference framework, we found that experiencing one or more sources of early adversity led to a 9 to 14% increase in females' glucocorticoid concentrations across adulthood. However, these effects were not mediated by weak social bonds: The direct effects of early adversity on adult glucocorticoid concentrations were 11 times stronger than the effects mediated by social bonds. This pattern occurred, in part, because the effect of social bonds on glucocorticoids was weak compared to the powerful effects of early adversity on glucocorticoid levels in adulthood. Hence, in female baboons, weak social bonds in adulthood are not enough to explain the effects of early adversity on glucocorticoid concentrations. Together, our results support the well-established notions that early adversity and weak social bonds both predict poor adult health. However, the magnitudes of these two effects differ considerably, and they may act independently of one another., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Vitamin D adequacy is essential for multiple physiologic processes. With limited exposure to sunlight for vitamin D 3 synthesis, captive primates are supplemented with vitamin D 3 (cholecalciferol). Vitamin D metabolite data from wild primates living indigenously could suggest optimum levels. The purpose of this study was to: 1) to explore whether baboons, a speciose genus whose members have significant exposed skin, coat color variation and wide geographical distribution, mirrors the skin pigmentation-vitamin D relationship found in humans; 2) compare vitamin D metabolite levels in wild and captive members of the same or similar baboon species; and 3) apply a recently developed method currently used in humans for measuring multiple vitamin D metabolites as a panel to explore if/how these metabolites can inform us on vitamin D sufficiency. Serum samples from males of three baboon species in the wild: Papio anubis (olive baboon, dark exposed skin), P. cynocephalus (yellow baboon, brown exposed skin), and P. hamadryas (hamadryas baboon, pink exposed skin), were compared with vitamin D supplemented captive olive baboons with sun exposure. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) measured vitamin D and its main metabolites. Cholecalciferol, 25 hydroxyvitamin D 2&3 (25(OH)D 2&3 ), and 24,25 dihydroxyvitamin D 2&3 (24,25(OH) 2 D 2&3 ), showed significant differences by species. The levels of cholecalciferol due to supplements in the captive olive baboons did not convert to higher 25(OH)D 3 while the wild olive baboons exhibited the lowest levels for both cholecalciferol and 25(OH)D 3 . Further metabolic conversion of 25(OH)D 3 to 24,25(OH) 2 D 3 indicated that all baboons had more similar conversion ratios and these were within the same range found for humans that are depicted as having adequate vitamin D levels. This study provided evidence that exposed skin color does influence vitamin D3 levels, with lower levels in darker skinned species, but these differences are eliminated in the downstream metabolite conversion indicating strong regulatory control., (© 2018 Wiley Periodicals, Inc.)

Understanding how environmental and social factors affect reproduction through variation in energetic condition remains understudied in wild animals, in large part because accurately and repeatedly measuring energetic condition in the wild is a challenge. Thyroid hormones (THs), such as triiodothyronine (T3) and thyroxine (T4), have a key role in mitigating metabolic responses to energy intake and expenditure, and therefore are considered important biomarkers of an animal's energetic condition. Recent method development has shown that T3 and T4 metabolites can be measured in feces, but studies measuring THs in wild populations remain rare. Here we measured fecal T3 metabolites (mT3) in baboons, and tested whether the conditions of collection and storage used for steroid hormones could also be used for mT3; we focused on mT3 as it is the biologically active form of TH and because fecal T4 metabolites (mT4) were below detection levels in our samples. We also tested if mT3 could be determined in freeze-dried samples stored for long periods of time, and if these concentrations reflected expected biological variations across seasons and reproductive states. Our results show that mT3 can be measured with accuracy and precision in baboon feces. The conditions of collection and storage we use for steroid hormones are appropriate for mT3 determination. In addition, mT3 concentrations can be determined in samples stored at -20 °C for up to 9 years, and are not predicted by the amount of time in storage. As expected, wild female baboons have lower mT3 concentrations during the dry season. Interestingly, mT3 concentrations are lower in pregnant and lactating females, possibly reflecting an energy sparing mechanism. Retroactive determination of mT3 concentration in stored, freeze-dried feces opens the door to novel studies on the role of energetic condition on fitness in wild animals., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Innovations in transgenic technology have facilitated improved xenograft survival. Additional gene expression appears to be necessary to overcome the remaining immune and biologic incompatibilities. We report for the first time the novel use of six-gene modifications within a pig-to-baboon cardiac xenotransplantation model., Methods: Baboons (8-15 kg) underwent heterotopic cardiac transplantation using xenografts obtained from genetically engineered pigs. Along with previously described modifications (GTKO, hCD46), additional expression of human transgenes for thromboregulation (endothelial protein C receptor, tissue factor pathway inhibitor, thrombomodulin), complement inhibition (decay accelerating factor), and cellular immune suppression (hCD39, hCD47) was used. Immunosuppression consisted of targeted T-cell and B-cell depletion and conventional anti-rejection agents., Results: Heterotopic cardiac transplantations were performed without complication. Flow cytometry and immunohistochemistry on donor biopsies confirmed transgenic phenotype. In contrast to the prior three-gene generation, significant coagulopathy or consumptive thrombocytopenia has not been observed in the six-gene cohort. As a result, these recipients have experienced decreased bleeding-related complications. Pro-inflammatory responses also appear to be mitigated based on cytokine analysis. Baboons survived the critical 30-day post-operative period when mortality has historically been highest, with no evidence of graft rejection., Conclusions: The inclusion of additional human genes in genetically engineered pigs appears to confer superior xenograft outcomes. Introduction of these genes has not been associated with adverse outcomes. This multifactorial approach to genetic engineering furthers the prospect of long-term cardiac xenograft survival and subsequent clinical application., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

In many mammals, maturational milestones such as dispersal and the attainment of adult dominance rank mark stages in the onset of reproductive activity and depend on a coordinated set of hormonal and socio-behavioral changes. Studies that focus on the link between hormones and maturational milestones are uncommon in wild mammals because of the challenges of obtaining adequate sample sizes of maturing animals and of tracking the movements of dispersing animals. We examined two maturational milestones in wild male baboons-adult dominance rank attainment and natal dispersal-and measured their association with variation in glucocorticoids (fGC) and fecal testosterone (fT). We found that rank attainment is associated with an increase in fGC levels but not fT levels: males that have achieved any adult rank have higher fGC than males that have not yet attained an adult rank. This indicates that once males have attained an adult rank they experience greater energetic and/or psychosocial demands than they did prior to attaining this milestone, most likely because of the resulting participation in both agonistic and sexual behaviors that accompany rank attainment. In contrast, natal dispersal does not produce sustained increases in either fGC or fT levels, suggesting that individuals are either well adapted to face the challenges associated with dispersal or that the effects of dispersal on hormone levels are ephemeral for male baboons., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Inhibition of procoagulant pathways may improve outcome in sepsis. We examined whether a dual short-acting thrombin (factor II) and factor X (FX)a inhibitor (SATI) ameliorates sepsis-induced disseminated intravascular coagulation (DIC) and is organ-protective., Methods: Escherichia coli were infused for 2 h in 22 anesthetized baboons. The control (CO) group (n = 8) received sterile isotonic solution only. In the treatment groups, SATI was administered starting 15 minutes after the end of the bacterial exposure. In the low-dose group (LD-SATI, n = 8), SATI was infused with 75 μg/kg/h for the first hour, followed by 23 μg/kg/h until the end of the study. In the high-dose SATI group (HD-SATI, n = 6), 225 μg/kg/h was administered for the first hour followed by continuous infusion of 69 μg/kg/h until termination of the study., Results: Sepsis-induced DIC was attenuated, as reflected by lower peak thrombin-antithrombin complexes (threefold) and D-dimer levels (twofold) in both SATI groups compared to the CO. This coincided with strongly improved cell/organ protection assessed by decreased levels of lactate dehydrogenase (threefold), creatinine (twofold), aspartate aminotransferase (threefold), and amylase (twofold) compared to the CO group. Anuria, which started at 8 h in the CO group, was prevented in both SATI groups. Peak interleukin-6 release at 12 h was prevented in the treatment groups. In both SATI groups, fewer catecholamines were necessary and no bleeding complications were observed., Conclusions: Dual inhibition of thrombin and FXa preserved activation of coagulation, protected organ function and ameliorated inflammation in severe Gram-negative sepsis in baboons. SATI could be a novel therapeutic agent against sepsis-induced DIC.

Glucose-dependent insulinotropic polypeptide (GIP) has important actions on whole body metabolic function. GIP and its receptor are also present in the central nervous system and have been linked to neurotrophic actions. Metabolic effects of central nervous system GIP signaling have not been reported. We investigated whether centrally administered GIP could increase peripheral plasma GIP concentrations and influence the metabolic response to a mixed macronutrient meal in nonhuman primates. An infusion and sampling system was developed to enable continuous intracerebroventricular (ICV) infusions with serial venous sampling in conscious nonhuman primates. Male baboons (Papio sp.) that were healthy and had normal body weights (28.9 ± 2.1 kg) were studied (n = 3). Animals were randomized to receive continuous ICV infusions of GIP (20 pmol·kg -1 ·h -1 ) or vehicle before and over the course of a 300-min mixed meal test (15 kcal/kg, 1.5g glucose/kg) on two occasions. A significant increase in plasma GIP concentration was observed under ICV GIP infusion (66.5 ± 8.0 vs. 680.6 ± 412.8 pg/ml, P = 0.04) before administration of the mixed meal. Increases in postprandial, but not fasted, insulin (P = 0.01) and pancreatic polypeptide (P = 0.04) were also observed under ICV GIP. Effects of ICV GIP on fasted or postprandial glucagon, glucose, triglyceride, and free fatty acids were not observed. Our data demonstrate that central GIP signaling can promote increased plasma GIP concentrations independent of nutrient stimulation and increase insulin and pancreatic polypeptide responses to a mixed meal., (Copyright © 2016 the American Physiological Society.)

Glycine is a co-agonist of glutamate at the NMDA receptor. Glycine transporter 1 (GlyT1) inhibitors are reported to be potential therapeutic agents for schizophrenia. (18)F-MK6577 is a new positron emission tomography (PET) radiotracer useful for imaging brain GlyT1 and its occupancy in humans. We devised a novel multi-infusion paradigm of radiolabeled and unlabeled compound and an iterative linear/nonlinear alternating fitting method to allow for the determination of in vivo affinity (Kd) and target concentration (Bmax) images, constraining Kd to be uniform across the brain. This paradigm was tested with (18)F-MK6577 in baboons. Voxel-based analysis produced high quality Bmax images and reliable Kd estimates, and also suggested that the nondisplaceable distribution volume (VND) is not uniform throughout the brain. In vivo GlyT1 Kd was estimated to be 1.87 nmol/L for (18)F-MK6577, and the rank order of GlyT1 distribution measured in the baboon brain was: high in the brainstem (133 nmol/L), medium in the cerebellum (83 nmol/L), and low in the cortex (30 nmol/L). These in vivo Kd and Bmax values agreed well with those determined in vitro, thus validating our novel multi-infusion approach.

Purpose: The objective of this study was to compare two different nebulizers: Eflow rapid® and Pari LC star® by scintigraphy and PK modeling to simulate epithelial lining fluid concentrations from measured plasma concentrations, after nebulization of CMS in baboons., Methods: Three baboons received CMS by IV infusion and by 2 types of aerosols generators and colistin by subcutaneous infusion. Gamma imaging was performed after nebulisation to determine colistin distribution in lungs. Blood samples were collected during 9 h and colistin and CMS plasma concentrations were measured by LC-MS/MS. A population pharmacokinetic analysis was conducted and simulations were performed to predict lung concentrations after nebulization., Results: Higher aerosol distribution into lungs was observed by scintigraphy, when CMS was nebulized with Pari LC® star than with Eflow Rapid® nebulizer. This observation was confirmed by the fraction of CMS deposited into the lung (respectively 3.5% versus 1.3%).CMS and colistin simulated concentrations in epithelial lining fluid were higher after using the Pari LC star® than the Eflow rapid® system., Conclusions: A limited fraction of CMS reaches lungs after nebulization, but higher colistin plasma concentrations were measured and higher intrapulmonary colistin concentrations were simulated with the Pari LC Star® than with the Eflow Rapid® system.

Intrauterine growth restriction increases the risk of perinatal complications and predisposes the infant to diabetes and cardiovascular disease in later life. Mechanisms by which maternal nutrient restriction (MNR) reduces fetal growth are poorly understood. We hypothesized that MNR decreases placental amino acid (AA) transporter activity, leading to reduced transplacental transfer of AAs. Pregnant baboons were fed either a control (ad libitum, n = 7), or MNR diet (70% of control diet, n = 7) from gestational day (GD) 30. At GD 165 (0.9 gestation), placentas (n = 7 in each group) were collected, and microvillous plasma membrane vesicles (MVM) isolated. MVM system A and system L AA transport was determined in vitro using radiolabeled substrates and rapid filtration techniques. In vivo transplacental AA transport was assessed by infusing nine (13)C- or (2)H-labeled essential AA as a bolus into the maternal circulation (n = 5 control, n = 4 MNR) at cesarean section. A fetal vein-to-maternal artery mole percent excess ratio for each essential AA was calculated. Fetal and placental weights were significantly reduced in the MNR group compared with controls (P < 0.01). The activity of system A and system L was markedly reduced by 73 and 84%, respectively, in MVM isolated from baboon placentas at GD 165 following MNR (P < 0.01). In vivo, the fetal vein-to-maternal artery mole percent excess ratio was significantly reduced for leucine, isoleucine, methionine, phenylalanine, threonine, and tryptophan in MNR baboons (P < 0.05). This is the first study to investigate placental AA transport in a nonhuman primate model of MNR. We demonstrate that the downregulation of system A and system L activity in syncytiotrophoblast MVM in MNR leads to decreased transplacental AA transport and, consequently, reduced circulating fetal AA concentrations, a potential mechanism linking maternal undernutrition to reduced fetal growth., (Copyright © 2015 the American Physiological Society.)

Reduced space can lead to crowding in social animals. Crowding increases the risk of agonistic interactions that, in turn, may require additional physiological defensive coping mechanisms affecting health. To determine the stress induced from increased social density in a group of nineteen baboons living in an indoor/outdoor enclosure, saliva cortisol levels and rates of anxiety-related behavior were analyzed across two unique crowding episodes. Initially, mean salivary cortisol levels when animals were restricted to their indoor quarters were compared to those when they also had access to their larger outdoor enclosure. Then, mean cortisol levels were compared before, during, and after two distinct crowding periods of long and short duration. Crowding resulted in significantly elevated cortisol during crowding periods compared to non-crowded periods. Cortisol levels returned to baseline following two crowding episodes contrasting in their length and ambient climate conditions. These cortisol elevations indicate greater metabolic costs of maintaining homeostasis under social stress resulting from reduced space. Self-directed behavior, conversely, was not reliably elevated during crowding. Results suggest that the potential for negative social interactions, and/or the uncertainty associated with social threat can cause physiological stress responses detected by salivary cortisol. Self-directed behavioral measures of stress may constitute inadequate indicators of social stress in colony-housed monkeys or represent subjective emotional arousal unrelated to hypothalamic-pituitary adrenal axis activation., (© 2015 Wiley Periodicals, Inc.)

Premature infants develop hyperglycemia shortly after birth, increasing their morbidity and death. Surviving infants have increased incidence of diabetes as young adults. Our understanding of the biological basis for the insulin resistance of prematurity and developmental regulation of glucose production remains fragmentary. The objective of this study was to examine maturational differences in insulin sensitivity and the insulin-signaling pathway in skeletal muscle and adipose tissue of 30 neonatal baboons using the euglycemic hyperinsulinemic clamp. Preterm baboons (67% gestation) had reduced peripheral insulin sensitivity shortly after birth (M value 12.5 ± 1.5 vs 21.8 ± 4.4 mg/kg · min in term baboons) and at 2 weeks of age (M value 12.8 ± 2.6 vs 16.3 ± 4.2, respectively). Insulin increased Akt phosphorylation, but these responses were significantly lower in preterm baboons during the first week of life (3.2-fold vs 9.8-fold). Preterm baboons had lower glucose transporter-1 protein content throughout the first 2 weeks of life (8%-12% of term). In preterm baboons, serum free fatty acids (FFAs) did not decrease in response to insulin, whereas FFAs decreased by greater than 80% in term baboons; the impaired suppression of FFAs in the preterm animals was paired with a decreased glucose transporter-4 protein content in adipose tissue. In conclusion, peripheral insulin resistance and impaired non-insulin-dependent glucose uptake play an important role in hyperglycemia of prematurity. Impaired insulin signaling (reduced Akt) contributes to the defect in insulin-stimulated glucose disposal. Counterregulatory hormones are not major contributors.

Baboons have natural antibodies against pig antigens. We have investigated whether there are differences in anti-non-Gal pig antibody levels between baboons maintained under specific pathogen-free (SPF) conditions and those housed under conventional conditions (non-SPF) that might be associated with improved outcome after pig-to-baboon organ transplantation. Baboons (n = 40) were housed indoors (SPF n = 8) or in indoor/outdoor pens (non-SPF n = 32) in colonies of similar size and structure. Non-SPF colonies harbor a number of pathogens common to non-human primate species, whereas many of these pathogens have been eliminated from the SPF colony. Complete blood cell counts (CBC), blood chemistry, and anti-non-Gal IgM and IgG levels were monitored. There were no significant differences in CBC or blood chemistry between SPF and non-SPF baboons. Anti-non-Gal IgM levels were significantly lower in the SPF baboons than in the non-SPF baboons (MFI 7.1 vs. 8.8, P < 0.05). One SPF and two non-SPF baboons had an MFI >20; if these three baboons are omitted, the mean MFIs were 4.8 (SPF) vs. 7.5 (non-SPF) (P < 0.05). Anti-non-Gal IgG was minimal in both groups (MFI 1.0 vs. 1.0). As their levels of anti-non-Gal IgM are lower, baboons maintained under SPF conditions may be beneficial for xenotransplantation studies as the initial binding of anti-pig IgM to an α1,3-galactosyltransferase gene-knockout pig organ may be less, thus resulting in less complement and/or endothelial cell activation. However, even under identical SPF conditions, an occasional baboon will express a high level of anti-non-Gal IgM, the reason for which remains uncertain., (© 2014 John Wiley & Sons A/S.)

Pneumococcal pneumonia is a leading cause of bacterial infection and death worldwide. Current diagnostic tests for detecting Streptococcus pneumoniae can be unreliable and can mislead clinical decision-making and treatment. To address this concern, we developed a preclinical model of pneumococcal pneumonia in nonhuman primates useful for identifying novel biomarkers, diagnostic tests, and therapies for human S. pneumoniae infection. Adult colony-bred baboons (n = 15) were infected with escalating doses of S. pneumoniae (Serotype 19A-7). We characterized the pathophysiological and serological profiles of healthy and infected animals over 7 days. Pneumonia was prospectively defined by the presence of three criteria: (1) change in white blood cell count, (2) isolation of S. pneumoniae from bronchoalveolar lavage fluid (BALF) or blood, and (3) concurrent signs/symptoms of infection. Animals given 10(9) CFU consistently met our definition and developed a phenotype of tachypnea, tachycardia, fever, hypoxemia, and radiographic lobar infiltrates at 48 hours. BALF and plasma cytokines, including granulocyte colony-stimulating factor, IL-6, IL-10, and IL-1ra, peaked at 24 to 48 hours. At necropsy, there was lobar consolidation with frequent pleural involvement. Lung histopathology showed alveolar edema and macrophage influx in areas of organizing pneumonia. Hierarchical clustering of peripheral blood RNA data at 48 hours correctly identified animals with and without pneumonia. Dose-dependent inoculation of baboons with S. pneumoniae produces a host response ranging from spontaneous clearance (10(6) CFU) to severe pneumonia (10(9) CFU). Selected BALF and plasma cytokine levels and RNA profiles were associated with severe pneumonia and may provide clinically useful parameters after validation.

Maternal undernutrition increases the risk of perinatal complications and predisposes offspring to obesity, diabetes, and cardiovascular disease later in life. Emerging evidence suggests that changes in placental function play a role in linking altered maternal nutrition in pregnancy to the subsequent development of adult disease. The susceptibility for disease in response to an adverse intrauterine environment differs distinctly between boys and girls, with girls typically having better outcomes. Here, we tested the hypothesis that regulation of the placental transcriptome by maternal nutrient reduction (NR) is dependent on fetal sex. We used a nonhuman primate model of NR in which maternal global food intake was reduced by 30% in baboons starting at gestational day (GD) 30. At GD 165 (term = GD 183), placental genome expression profiling of 6 control (n = 3 females, 3 males) and 6 nutrient restricted (n = 3 females, 3 males) fetuses was carried out followed by bioinformatic analysis. Surprisingly, there was no coordinated placental molecular response to decreased nutrient availability when analyzing the data without accounting for fetal sex. In contrast, female placentas exhibited a highly coordinated response that included upregulation of genes in networks, pathways, and functional groups related to programmed cell death and downregulation of genes in networks, pathways, and functional groups associated with cell proliferation. These changes were not apparent in the male placentas. Our data support the concept that female placentas initiate complex adaptive responses to an adverse intrauterine environment, which may contribute to increased survival and better pregnancy outcomes in girls.

Theropithecus was a common large-bodied primate that co-occurred with hominins in many Plio-Pleistocene deposits in East and South Africa. Stable isotope analyses of tooth enamel from T. brumpti (4.0-2.5 Ma) and T. oswaldi (2.0-1.0 Ma) in Kenya show that the earliest Theropithecus at 4 Ma had a diet dominated by C4 resources. Progressively, this genus increased the proportion of C4-derived resources in its diet and by 1.0 Ma, had a diet that was nearly 100% C4-derived. It is likely that this diet was comprised of grasses or sedges; stable isotopes cannot, by themselves, give an indication of the relative importance of leaves, seeds, or underground storage organs to the diet of this primate. Theropithecus throughout the 4- to 1-Ma time range has a diet that is more C4-based than contemporaneous hominins of the genera Australopithecus, Kenyanthropus, and Homo; however, Theropithecus and Paranthropus have similar proportions of C4-based resources in their respective diets.

θ-Defensins are the only natural cyclic proteins found in primates. They have strong antimicrobial activity related to their trisulfide ladders and macrocyclic conformation. A non-cyclic baboon θ-defensin (BTD) was synthesized by substituting valine with phenylalanine at position 17, at the C-terminal end of the BTD; this was termed "BTD-S." The antimicrobial activities of this synthetic peptide were investigated against Escherichia coli and two cotton phytopathogens: Verticillium dahliae and Fusarium oxysporum. The minimum inhibitory concentration (MIC) of BTD-S for E. coli was 10 μg/mL and for V. dahliae was 5 μg/mL, significantly lower than that for F. oxysporum (40.0 μg/mL). A time course analysis of fungal cultures indicated that the growth of V. dahliae was completely inhibited after 96 h of BTD-S treatment. Furthermore, hemolysis assays revealed that BTD-S was not toxic to mammalian cells as it could not induce lysis of sheep red blood cells even at ten times the MIC (50 μg/mL). Scanning electron microscopy and double-stained (calcofluor white and propidium iodide binding) fluorescence microscopy showed that exposure of spores of V. dahliae to BTD-S either disabled normal germination or disintegrated the spores. The size of cells exposed to BTD-S was significantly reduced compared with controls, and their number increased in a dose-dependent curve when measured by flow cytometry. These findings suggest that BTD-S has great potential to inhibit the growth of V. dahliae and can be utilized as an effective remedy to control economic losses caused by Verticillium wilt in the development of wilt-resistant cotton.

Purpose: (11)C-GSK931145 is a novel radioligand suitable for imaging the glycine transporter 1 (GlyT-1) in brain. In the present study, human dosimetry is estimated from baboon and human biodistribution data., Procedures: Three baboons and eight healthy human volunteers underwent whole-body positron emission tomography (PET) scans. Human dosimetry was estimated using three different region-of-interest (ROI) delineation methods that ranged in their complexity and execution time: ROIs drawn on anterior-posterior compressed PET images, on subsamples of the organs, and covering the whole-organ. Residence times for each organ were calculated as the area under the time-activity curves divided by the injected activity. Radiation dose estimates were calculated from organ residence times using the OLINDA/EXM software package., Results: The overall distribution of activity was similar in baboons and humans. Early scans presented high activity in the liver, and moderate activity in the lungs and kidneys. The principal route of clearance was intestinal and no urinary excretion was observed. The limiting organ with the highest radiation-absorbed dose was the liver. The mean effective dose in humans was 4.02 μSv/MBq (male phantom) and 4.95 μSv/MBq (female phantom) (ROIs drawn on subsamples of the organs). The human effective dose estimated from baboon data was ~15% larger than the effective dose estimated from human data., Conclusion: Human PET imaging of the glycine transporter-1 with (11)C-GSK931145 results in a moderate effective human radiation dose, which allows for multiple PET examinations in the same individual. Among the three methods compared to delineate ROIs, the organ subsampling method shows the best balance between quantitative accuracy and practical application.

Recognition of the strength of nonhuman primate models in investigating metabolic disorders has resulted in an expanded need for in vivo research techniques. We studied adipose metabolism in 10 baboons (13.0 ± 4.2 years old, 29.5 ± 5.5 kg). Part 1 evaluated the effect of different sedatives on the rate of appearance of plasma free fatty acids (RaFFA), assessed using ¹³C₄-labeled palmitate infusion (7 µmol/kg/min). Animals, were studied with no sedation, with complete isoflurane sedation, and with minimal midazolam infusion (0.04 mg/kg/h), with the last scheme allowing for the most consistent values and animals that were visually more calm. In Part 2, RaFFA and RaGlycerol (D₅-glycerol, 5 mg/kg lean body mass/h) were measured. From midnight to 0300, flux fell and came to a steady state between 0500 and 0700 h (RaFFA, 39.4 ± 29.8 μmol/kg fat mass/min; and RaGlycerol, 26.9 ± 7.3 μmol/kg/min). The RaFFA-to-RaGlycerol ratio was 1.5 ± 0.8 (49% reesterification). The decline in turnover throughout the night reflects natural circadian processes and was mirrored by reductions in FFA and glycerol to 0.62 and ± 0.14 and 0.16 and ± 0.03 mmol/l, respectively. The concurrent changes in both FFA and glycerol kinetics indicate physiologic validity of the method. These techniques will support needed research to determine mechanisms by which treatments act upon the adipocyte in vivo.

In conditions characterized by energetic constraints, such as in periods of low food availability, some trade-offs between reproduction and self-maintenance may be necessary; even year-round breeders may then be forced to exhibit some reproductive seasonality. Prior research has largely focused on female reproduction and physiology, and few studies have evaluated the impact of environmental factors on males. Here we assessed the effects of season and ambient temperatures on fecal glucocorticoid (fGC) and testosterone (fT) levels in male baboons in Amboseli, Kenya. The Amboseli basin is a highly challenging, semiarid tropical habitat that is characterized by strongly seasonal patterns of rainfall and by high ambient temperatures. We previously reported that female baboons were impacted by these challenging environmental conditions. We ask here whether male baboons in the same environment and groups as females exhibit similar physiological effects. We found that after accounting for male age and individual variability, males exhibited higher fGC levels and lower fT levels during the dry season than during the wet season. Furthermore, fT but not fGC levels were lower in months of high average daily maximum temperatures, suggesting a direct impact of heat on testes. Our results demonstrate that male baboons, like females, experience ecological stress that alters their reproductive physiology. The impact of the environment on male reproduction deserves more attention both in its own right and because alteration in male physiology may contribute to the reduction in female fertility observed inchallenging environments., (2010 Wiley-Liss, Inc.)

In the 75 years since the seminal observation of Clive McCay that restriction of calorie intake extends the lifespan of rats, a great deal has been learned about the effects of calorie restriction (CR; reduced intake of a nutritious diet) on aging in various short-lived animal models. Studies have demonstrated many beneficial effects of CR on health, the rate of aging, and longevity. Two prospective investigations of the effects of CR on long-lived nonhuman primate (NHP) species began nearly 25 years ago and are still under way. This review presents the design, methods, and main findings of these and other important contributing studies, which have generally revealed beneficial effects of CR on physiological function and the retardation of disease consistent with studies in other species. Specifically, prolonged CR appears to extend the lifespan of rhesus monkeys, which exhibited lower body fat; slower rate of muscle loss with age; lower incidence of neoplasia, cardiovascular disease, type 2 diabetes mellitus, and endometriosis; improved insulin sensitivity and glucose tolerance; and no apparent adverse effect on bone health, as well as a reduction in total energy expenditure. In addition, there are no reports of deleterious effects of CR on reproductive endpoints, and brain morphology is preserved by CR. Adrenal and thyroid hormone profiles are inconsistently affected. More research is needed to delineate the mechanisms of the desirable outcomes of CR and to develop interventions that can produce similar beneficial outcomes for humans. This research offers tremendous potential for producing novel insights into aging and risk of disease.

Extracellular matrix metalloproteinase inducer (EMMPRIN; BSG) regulates tissue remodeling through matrix metalloproteinases (MMPs). In human and non-human primates, endometrial remodeling is important for menstruation and the pathogenesis of endometriosis. We hypothesized that as in humans, BSG and MMPs are expressed in the endometrium of cycling baboons, and their expression is hormonally regulated by ovarian hormones, but endometriosis disrupts this regulation. BSG expression was evaluated in the baboon endometrium by q-PCR and immunohistochemistry. In the endometrium of control cycling animals, BSG mRNA levels were highest in late secretory stage tissue. BSG protein localized to glandular epithelial cells during the proliferative phase; whereas, secretory stage tissues expressed BSG in glandular and luminal epithelia with weak stromal staining. Several MMPs were differentially expressed throughout the menstrual cycle with the highest levels found during menstruation. In ovariectomized animals, BSG endometrial mRNA levels were highest with treatment of both estrogen and progesterone than that with only estrogen. Estrogen alone resulted in BSG protein localization primarily in the endometrial glandular epithelia, while estrogen and progesterone treatment displayed BSG protein localization in both the glandular and stromal cells. Exogenous hormone treatment resulted in differential expression patterns of all MMPs compared with the control cycling animals. In the eutopic endometrium of endometriotic animals, BSG mRNA levels and protein were elevated early but decreased later in disease progression. Endometriosis elevated the expression of all MMPs except MMP7 compared with the control animals. In baboons, BSG and MMP endometrial expression is regulated by both ovarian hormones, and their expression patterns are dysregulated in endometriotic animals.

The assessment of relatedness may be crucial in the evolution of socio-sexual behaviour, because it can be associated with fitness benefits mediated by both nepotism and inbreeding avoidance. In this context, one proposed mechanism for kin recognition is 'phenotype matching'; animals might compare phenotypic similarities between themselves and others in order to assess the probability that they are related. Among cues potentially used for kin discrimination, body odours constitute interesting candidates that have been poorly investigated in anthropoid primates so far, because of a mixture of theoretical considerations and methodological/experimental constraints. In this study, we used an indirect approach to examine the similarity in odour signals emitted by related individuals from a natural population of chacma baboons (Papio ursinus). For that purpose, we designed an innovative behavioural tool using mice olfactory abilities in a habituation-discrimination paradigm. We show that: (i) mice can detect odour differences between individuals of same sex and age class in another mammal species, and (ii) mice perceive a higher odour similarity between related baboons than between unrelated baboons. These results suggest that odours may play a role in both the signalling of individual characteristics and of relatedness among individuals in an anthropoid primate. The 'biological olfactometer' developed in this study offers new perspectives to the exploration of olfactory signals from a range of species.

Decreased maternal nutrient availability during pregnancy induces compensatory fetal metabolic and endocrine responses. Knowledge of cellular changes involved is critical to understanding normal and abnormal development. Several studies in rodents and sheep report increased fetal plasma cortisol and associated increased gluconeogenesis in response to maternal nutrient reduction (MNR) but observations in primates are lacking. We determined MNR effects on fetal liver phosphoenolpyruvate carboxykinase 1 (protein, PEPCK1; gene, PCK1 orthologous/homologous human chromosomal region 20q13.31) at 0.9 gestation (G). Female baboon social groups were fed ad libitum (control, CTR) or 70% CTR (MNR) from 0.16 to 0.9G when fetuses were delivered by caesarean section under general anaesthesia. Plasma cortisol was elevated in fetuses of MNR mothers (P < 0.05). Immunoreactive PEPCK1 protein was located around the liver lobule central vein and was low in CTR fetuses but rose to 63% of adult levels in MNR fetuses. PCK1 mRNA measured by QRT-PCR increased in MNR (2.3-fold; P < 0.05) while the 25% rise in protein by Western blot analysis was not significant. PCK1 promoter methylation analysis using bisulfite sequencing was significantly reduced in six out of nine CpG-dinucleotides evaluated in MNR compared with CTR liver samples. In conclusion, these are the first data from a fetal non-human primate indicating hypomethylation of the PCK1 promoter in the liver following moderate maternal nutrient reduction.

Background: Cigarette smoking and nicotine have complex effects on human physiology and behavior, including some effects similar to those elicited by inhibition of aromatase, the last enzyme in estrogen biosynthesis. We report the first in vivo primate study to determine whether there is a direct effect of nicotine administration on brain aromatase., Methods: Brain aromatase availability was examined with positron emission tomography and the selective aromatase inhibitor [(11)C]vorozole in six baboons before and after exposure to IV nicotine at .015 and .03 mg/kg., Results: Nicotine administration produced significant, dose-dependent reductions in [(11)C]vorozole binding. The amygdala and preoptic area showed the largest reductions. Plasma levels of nicotine and its major metabolite cotinine were similar to those found in cigarette smokers., Conclusions: Nicotine interacts in vivo with primate brain aromatase in regions involved in mood, aggression, and sexual behavior., (Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

The front-line tuberculosis (TB) chemotherapeutics isoniazid (INH), rifampicin (RIF), and pyrazinamide (PZA) have been labeled with carbon-11 and the biodistribution of each labeled drug has been determined in baboons using positron emission tomography (PET). Each radiosynthesis and formulation has been accomplished in 1 h, using [(11)C]CH(3)I to label RIF and [(11)C]HCN to label INH and PZA. Following iv administration, INH, PZA, RIF, and/or their radiolabeled metabolites clear rapidly from many tissues; however, INH, PZA, and/or their radiolabeled metabolites accumulate in the bladder while RIF and/or its radiolabeled metabolites accumulates in the liver and gall bladder, consistent with the known routes of excretion of the drugs. In addition, the biodistribution data demonstrate that the ability of the three drugs and their radiolabeled metabolites to cross the blood-brain barrier decreases in the order PZA > INH > RIF, although in all cases the estimated drug concentrations are greater than the minimum inhibitory concentration (MIC) values for inhibiting bacterial growth of Mycobacterium tuberculosis (MTB). The pharmacokinetic (PK) and drug distribution data have important implications for treatment of disseminated TB in the brain and pave the way for imaging the distribution of the pathogen in vivo.

[(11)C]befloxatone is a high-affinity, reversible, and selective radioligand for the in vivo visualization of the monoamine oxidase A (MAO-A) binding sites using positron emission tomography (PET). The multi-injection approach was used to study in baboons the interactions between the MAO-A binding sites and [(11)C]befloxatone. The model included four compartments and seven parameters. The arterial plasma concentration, corrected for metabolites, was used as input function. The experimental protocol-three injections of labeled and/or unlabeled befloxatone-allowed the evaluation of all the model parameters from a single PET experiment. In particular, the brain regional concentrations of the MAO-A binding sites (B'(max)) and the apparent in vivo befloxatone affinity (K(d)) were estimated in vivo for the first time. A high binding site density was found in almost all the brain structures (170+/-39 and 194+/-26 pmol/mL in the frontal cortex and striata, respectively, n=5). The cerebellum presented the lowest binding site density (66+/-13 pmol/mL). Apparent affinity was found to be similar in all structures (K(d)V(R)=6.4+/-1.5 nmol/L). This study is the first PET-based estimation of the B(max) of an enzyme.

Glucuronidation by UDP-glucuronyltransferase 2B enzymes (UGT2Bs) is a major pathway for the elimination of endobiotics and xenobiotics, including therapeutic drugs. Morphine, a probe drug for UGT2B7, is metabolized to morphine-3-beta-glucuronide (M3G) and morphine-6-beta-glucuronide (M6G) in humans. Morphine has been used in a series of experiments in the baboon to characterize developmental changes in fetal glucuronidation. This study identifies the baboon UGT2B family of enzymes, compares them with that of the human and the monkey (Macaca fascicularis), and measures the activity of the individual baboon UGT2Bs toward morphine. UGT2B cDNAs were cloned from the liver of adult and newborn baboons and expressed in human embryonic kidney 293 cells. The UGT activity toward morphine was assessed by the rate of formation of M3G and M6G by high-performance liquid chromatography. Eight baboon UGT2Bs were cloned and identified: UGT2B41 and UGT2B42, which are 90% homologous to human UGT2B4; UGT2B43, which is 93% homologous to human UGT2B15; and UGT2B39, UGT2B40, UGT2B44, UGT2B45, and UGT2B46, which are 89 to 91% homologous to human UGT2B7. Homology between baboon and monkey UGT2B ranged from 92.6 to 99.1%, with the primary protein structure of UGT2B43 being 99.1% identical to monkey UGT2B20, including a unique R96I substitution. Gene conversion interfered with the phylogenetic signal in the baboon UGT2B7-like and the monkey UGT2B4-like groups and led to concerted evolution of these enzymes. All of the baboon UGT2Bs metabolized morphine to both M3G and M6G. This study lays the foundation for investigating the regulation of UGT2B enzymes during fetal and neonatal development in the baboon.

The aim of the present study was to conduct a semiquantitative immunohistochemical investigation into the levels of intermediary proteins within the nuclear factor (NF)-kappaB pathway throughout the menstrual cycle in a non-human primate, namely the baboon (Papio anubis), with and without endometriosis. Formalin-fixed eutopic (n = 2-4) and ectopic (n = 6-7) endometrial tissues from baboons at the mid-luteal phase were embedded in paraffin and examined for NF-kappaB pathway components (i.e. IkappaB kinase (IKK) alpha, IKKbeta, phosphorylated (phospho-) IkappaBalpha and phospho-NF-kappaB p65 subunit), ubiquitin, 19S proteasome and the NF-kappaB activator tumour necrosis factor (TNF)-alpha. Similarly, endometrial tissues from baboons at the late follicular, mid-luteal and menses phase (n = 2-4) were investigated to determine the levels of these proteins throughout the menstrual cycle. Cytoplasmic stromal IKKalpha and glandular 19S proteasome immunostaining was elevated in the ectopic endometrium, whereas levels of ubiquitin, phospho-p65, IKKbeta, TNF-alpha and nuclear 19S proteasome were similar in the eutopic and ectopic endometrium. A significant decrease in phospho-IkappaBalpha nuclear immunostaining was observed within glandular cells of the ectopic endometrium. In the eutopic endometrium, IKKalpha, ubiquitin and 19S proteasome immunostaining was elevated in different phases of the menstrual cycle, whereas levels of phospho-p65, IKKbeta, phospho-IkappaBalpha and TNF-alpha remained unchanged. We have demonstrated that, in the baboon endometriosis model, levels of IKKalpha immunostaining are elevated, whereas those of phospho-IkappaBalpha are reduced, consistent with the hypothesis that excessive NF-kappaB activity plays a role in reducing ectopic endometrial apoptosis, which contributes to the pathophysiology of endometriosis. Further studies are required to confirm a causal association between elevated IKKalpha levels and reduced endometrial apoptosis.

Fatty acid desaturase 1 and 2 (FADS1 and FADS2) code for the key desaturase enzymes involved in the biosynthesis of long chain polyunsaturated fatty acids in mammals. FADS3 shares close sequence homology to FADS1 and FADS2 but the function of its gene product remains unknown. Alternative transcripts (AT) generated by alternative splicing (AS) are increasingly recognized as an important mechanism enabling a single gene to code for multiple gene products. We report the first AT of a FADS gene, FADS3, generated by AS. Aided by ORF Finder, we identified putative coding regions of eight AT for FADS3 with 1.34 kb (classical splicing), 1.14 (AT1), 0.77 (AT2), 1.25 (AT3), 0.51 (AT4), 0.74 (AT6), and 1.11 (AT7). In addition we identified a 0.51 kb length transcript (AT5) that has a termination codon within intron 8-9. The expression of each AT was analyzed in baboon neonate tissues and in differentiated and undifferentiated human SK-N-SH neuroblastoma cells. FADS3 AT are expressed in 12 neonate baboon tissues and showed reciprocal increases and decreases in expression changes in response to human neuronal cell differentiation. FADS3 AT, conserved in primates and under metabolic control in human cells, are a putative mediator of LCPUFA biosynthesis and/or regulation.

Background: A sub-optimal intrauterine environment alters the trajectory of fetal development with profound effects on life-time health. Altered methylation, a proposed epigenetic mechanism responsible for these changes, has been studied in non-primate species but not nonhuman primates. We tested the hypotheses that global methylation in fetal baboon demonstrates organ specificity, gestational age specificity, and changes with maternal nutritional status., Methods: We measured global DNA methylation in fetuses of control fed (CTR) and nutrient restricted mothers fed 70% of controls (MNR) for brain, kidney, liver and heart at 0.5 and 0.9 gestation (G)., Results: We observed organ and gestation specific changes that were modified by maternal diet. Methylation in CTR fetuses was highest in frontal cortex and lowest in liver. MNR decreased methylation in 0.5G kidney and increased methylation in 0.9G kidney and frontal cortex., Conclusion: These results demonstrate a potential epigenetic mechanism whereby reduced maternal nutrition has long-term programming effects on fetal organ development.

We employed a novel approach to identify the key loci that harbor genes influencing lipoprotein metabolism in approximately 2,000 pedigreed baboons fed various diets differing in levels of fat and cholesterol. In this study, 126 overlapping traits related to both LDL and HDL metabolism were normalized and subjected to genome-wide linkage screening. As was expected, the traits were highly, but not completely, correlated. We exploited the information in these correlated traits by focusing on those genomic regions harboring quantitative trait loci (QTL) for multiple traits, reasoning that the more influential genes would impact a larger number of traits. This study identified five major QTL clusters (each with at least two significant logarithm of the odds scores >4.7), two of which had not been previously reported in baboons. One of these mapped to the baboon ortholog of human chromosome 1p32-p34 and influenced concentrations of LDL-cholesterol on Basal and high-fat, low-cholesterol diets. The other novel QTL cluster mapped to the baboon ortholog of human chromosome 12q13.13-q14.1 and influenced LDL size properties on high-fat, low-cholesterol and high-fat, high-cholesterol, but not Basal, diets. Confirming the value of this approach, three of the QTL clusters replicated published linkage findings for the same or similar traits.

Circulating cortisol levels are often used to assess the biological stress response in captive primates. Some methods commonly used to collect blood samples may alter the stress response. As such, noninvasive means to analyze cortisol levels are increasingly being developed. We adapted an existing collection method to simultaneously obtain saliva from multiple socially living hamadryas baboons (Papio hamadryas hamadryas) and validated an enzyme-immunoassay kit to quantify cortisol within the saliva samples. Over a period of 12 months, saliva samples were regularly collected from approximately half of the 18-member colony, representing younger monkeys who were more willing to participate. The assay met the four criteria typically used to assess the effectiveness of a new analytical technique: parallelism, precision, accuracy, and sensitivity. Cortisol levels were also proportional to those expected given published plasma levels of cortisol in baboons. Further, salivary cortisol levels increased in individuals following significant stress-related events, such as removal from the group, indicating biological validation. The technique provided a reliable and effective means to assess a physiological indicator of stress in a social group without initiating a stress response owing to handling or sedation, and provided a real-time assessment of cortisol levels and reactivity.

Dominance status and reproductive experience are maternal characteristics that affect offspring traits in diverse taxa, including some cercopithecine primates. Maternal effects of this sort are widespread and are sources of variability in offspring fitness. We tested the hypothesis that maternal dominance rank and reproductive experience as well as a male's own age and dominance rank predicted chronic fecal glucocorticoid (fGC) concentrations in 17 subadult wild male baboons, Papio cynocephalus (median age 6.5 years), in the Amboseli basin, Kenya. Among these variables, maternal dominance rank at a subadult male's conception was the sole significant predictor of the male's fGC and accounted for 42% of fGC variance; sons of lower ranking mothers had higher fGC than did those of high-ranking mothers. This result is striking because subadult male baboons are approximately 4-6 years past the period of infant dependence on their mothers, and are larger than and dominant to all adult females. In addition, many males of this age have survived their mothers' death. Consequently, the influence of maternal dominance rank persisted well beyond the stage at which direct maternal influence on sons is likely. Persistence of these major maternal influences from the perinatal period may signal organizational effects of mothers on sons' HPA axis. Although short-term, acute, elevations in GC are part of adaptive responses to challenges such as predators and other emergencies, chronically elevated GC are often associated with stress-related pathologies and, thereby, adverse effects on fitness components.

Unlabelled: The methamphetamine molecule has a chiral center and exists as 2 enantiomers, d-methamphetamine (the more active enantiomer) and l-methamphetamine (the less active enantiomer). d-Methamphetamine is associated with more intense stimulant effects and higher abuse liability. The objective of this study was to measure the pharmacokinetics of d-methamphetamine for comparison with both l-methamphetamine and (-)-cocaine in the baboon brain and peripheral organs and to assess the saturability and pharmacologic specificity of binding., Methods: d- and l-methamphetamine and (-)-cocaine were labeled with (11)C via alkylation of the norprecursors with (11)C-methyl iodide using literature methods. Six different baboons were studied in 11 PET sessions at which 2 radiotracer injections were administered 2-3 h apart to determine the distribution and kinetics of (11)C-d-methamphetamine in brain and peripheral organs. Saturability and pharmacologic specificity were assessed using pretreatment with d-methamphetamine, methylphenidate, and tetrabenazine. (11)C-d-Methamphetamine pharmacokinetics were compared with (11)C-l-methamphetamine and (11)C-(-)-cocaine in both brain and peripheral organs in the same animal., Results: (11)C-d- and l-methamphetamine both showed high uptake and widespread distribution in the brain. Pharmacokinetics did not differ between enantiomers, and the cerebellum peaked earlier and cleared more quickly than the striatum for both. (11)C-d-Methamphetamine distribution volume ratio was not substantially affected by pretreatment with methamphetamine, methylphenidate, or tetrabenazine. Both enantiomers showed rapid, high uptake and clearance in the heart and lungs and slower uptake and clearance in the liver and kidneys. A comparison of (11)C-d-methamphetamine and (11)C-(-)-cocaine showed that (11)C-d-methamphetamine peaked later in the brain than did (11)C-(-)-cocaine and cleared more slowly. The 2 drugs showed similar behavior in all peripheral organs examined except the kidneys and pancreas, which showed higher uptake for (11)C-d-methamphetamine., Conclusion: Brain pharmacokinetics did not differ between d-and l-methamphetamine and thus cannot account for the more intense stimulant effects of d-methamphetamine. Lack of pharmacologic blockade by methamphetamine indicates that the PET image represents nonspecific binding, though the fact that methamphetamine is both a transporter substrate and an inhibitor may also play a role. A comparison of (11)C-d-methamphetamine and (11)C-(-)-cocaine in the same animal showed that the slower clearance of methamphetamine is likely to contribute to its previously reported longer-lasting stimulant effects relative to those of (-)-cocaine. High kidney uptake of d-methamphetamine or its labeled metabolites may account for the reported renal toxicity of d-methamphetamine in humans.

Chorionic gonadotropin (CG) is an early embryo-derived signal that is known to support the corpus luteum. An in vivo baboon model was used to study the direct actions of human CG (hCG) on the endometrium, during the periimplantation period. Endometrial gene expression was analyzed using microarrays. The endometrial biopsies were taken from hCG-treated (n = 5) and control (n = 6) animals on d 10 after ovulation. Class comparison identified 61 genes whose transcript levels differed between control and hCG-treated samples (48 increased, 13 decreased in mean expression level more than 2.5-fold; P < 0.01). Real-time PCR of transcript abundance confirmed up-regulation of several of these, including SerpinA3, matrix metalloproteinase 7, leukemia inhibitory factor (LIF), IL-6, and Complement 3 (P

Although the human and the nonhuman primate fetal adrenal glands undergo a highly unique pattern of cortical zone-specific intrauterine growth and development, studies of the regulatory components of the cell cycle responsible for this growth have not been conducted. Therefore, the present study determined expression of the cell cycle regulators, cyclin D1 and cyclin E, and their cyclin-dependent kinases, Cdk2, Cdk4, and Cdk6, and Ki67 a marker of cell proliferation within the baboon fetal adrenal cortex during advancing stages of gestation. Fetal adrenal glands were obtained on days 60 (early), 100 (mid), and 160-170 (late) of gestation (term = 184 days). Mean (+/- s.e.) cyclin D1 mRNA levels, determined by RT-PCR and expressed relative to 18S rRNA, were similar at early (0.85 +/- 0.09) and mid (1.04 +/- 0.08) gestation, then decreased (P < 0.001, ANOVA) approximately 50% by late gestation (0.57 +/- 0.04). Cyclin E mRNA levels were also similar at early (2.03 +/- 0.07) and mid (1.63 +/- 0.31) gestation, and decreased by 70% (P < 0.001) in late gestation (0.53 +/- 0.09). Coinciding with the decrease in cyclin D1 and cyclin E, the percentage of Ki67 positive cells in the definitive zone decreased twofold (P < 0.01) between mid (28.2 +/- 3.6) and late (13.8 +/- 1.7) gestation. The cyclin D1 and cyclin E proteins, determined by immunocytochemistry, were expressed at high levels in the definitive zone of baboon fetal adrenal gland, where they decreased between mid- and late gestation. In contrast, immunocytochemical expression of the functionally important steroidogenic enzyme Delta(5)-3beta-hydroxysteroid dehydrogenase (3beta-HSD) became abundant in the definitive and transitional zones with advancing pregnancy. However, fetal adrenal Cdk2, Cdk4, and Cdk6 mRNA levels and protein immunoexpression were similar in the baboon fetal adrenal at early-, mid-, and late gestation. In summary, expression of cyclin D1, cyclin E, and Ki67 decreased, while 3beta-HSD expression increased, in the fetal adrenal cortex, particularly in the definitive zone, between mid- and late-baboon gestation. We propose that a developmental decline in cellular proliferation permits functional differentiation of fetal adrenal cortical cells, leading to increased production of steroid hormones important for placental estrogen synthesis and maturation of organ systems within the developing fetus.

Background: In pregnant primates, the effect of post-prandial hyperglycemic or insulinemic states on leptin production is not known. Our goal was to conduct a controlled study using an established pregnant baboon model ( PAPIO ANUBIS) to determine whether acute glucose changes would have an effect on maternal or fetal plasma leptin levels., Methods: Two animals were operated on at 138 and 140 days of gestation (term approximately 184 days) by placing 4 cannulae in the maternal aorta, inferior vena cava, fetal carotid artery, and the amniotic cavity. At 145 and 150 days, glucose infusions were started via the maternal femoral vein. Animal 1 received 7.5 gm of glucose over a 2-hour period at 145 th day. Animal 2 received 20 gm of glucose over a 1-hour period at 150th day. Both animals remained ad libitum throughout the experiments. Maternal and fetal blood samples were obtained from the arterial lines before the glucose infusion and at half hour intervals to include 30 minutes post-infusion., Results: Significant changes from baseline concentrations were observed for maternal and fetal glucose and insulin concentrations in response to both glucose challenges. Maternal and fetal plasma leptin concentrations did not correlate with glucose or insulin changes., Conclusion: This preliminary study demonstrated that in primates, acute changes in circulating maternal or fetal glucose or insulin concentration do not affect maternal or fetal plasma leptin concentrations. These results suggest that alterations in leptin secretion by the maternal-placental-fetal unit may only occur in pathological states.

Interpretation of gene array data presents many potential pitfalls in adult tissues. Gene array techniques applied to fetal tissues present additional confounding pitfalls. The left lobe of the fetal liver is supplied with blood containing more oxygen than the right lobe. Since synthetic activity and cell function are oxygen dependent, we hypothesized major differences in mRNA expression between the fetal right and left liver lobes. Our aim was to demonstrate the need to evaluate RNA samples from both lobes. We performed whole genome expression profiling on left and right liver lobe RNA from six 90-day gestation baboon fetuses (term 180 days). Comparing right with left, we found 875 differentially expressed genes - 312 genes were up-regulated and 563 down-regulated. Pathways for damaged DNA binding, endonuclease activity, interleukin binding and receptor activity were up-regulated in right lobe; ontological pathways related to cell signalling, cell organization, cell biogenesis, development, intracellular transport, phospholipid metabolism, protein biosynthesis, protein localization, protein metabolism, translational regulation and vesicle mediated transport were down-regulated in right lobe. Molecular pathway analysis showed down-regulation of pathways related to heat shock protein binding, ion channel and transporter activities, oxygen binding and transporter activities, translation initiation and translation regulator activities. Genes involved in amino acid biosynthesis, lipid biosynthesis and oxygen transport were also differentially expressed. This is the first demonstration of RNA differences between the two lobes of the fetal liver. The data support the argument that a complete interpretation of gene expression in the developing liver requires data from both lobes.

Previous studies in rodents and sheep show that maternal nutrient restriction during pregnancy alters fetal renal development. To date, no studies using fetal baboon RNA with human Affymetrix gene chips have been published. In the present study we have (1) evaluated the specificity of the Affymetrix human gene array 'Laboratory on a Chip' system for use with fetal baboon mRNA and (2) investigated the effects of moderate maternal global nutrient restriction (NR; 70% of ad libitum animals) from early (30 days gestation (dG)) to mid-gestation (90 dG; term = 184 dG) on the fetal baboon kidney. Morphometric and blood measurements were made on 12 non-pregnant baboons before they were bred. All baboons were fed ad libitum until 30 days pregnant, at which time six control baboons continued to feed ad libitum (control - C) while six received 70% of the C diet on a weight adjusted basis. Fetal kidneys were collected following caesarean section at 90 dG, with samples flash frozen and fixed for histological assessment. Fetal hip circumference was decreased in the NR group (68 +/- 2 versus 75 +/- 2 mm), while fetal body weight and all other measurements of fetal size were not different between C and NR at 90 dG. Maternal body weight was decreased in the NR group (12.16 +/- 0.34 versus 13.73 +/- 0.55 kg). Having established the specificity of the Affymetrix system for fetal baboon mRNA, gene expression profiling of fetal kidneys in the context of our maternal nutrient restriction protocol shows that NR resulted in a down-regulation of genes in pathways related to RNA, DNA and protein biosynthesis, metabolism and catabolism. In contrast, genes in cell signal transduction, communication and transport pathways were up-regulated in the NR group. These changes indicate that even a moderate level of maternal global NR impacts fetal renal gene pathways. Our histological assessment of renal structure indicates decreased tubule density within the cortex of NR kidneys compared with controls. The number of glomerular cross-sections per unit area were unaffected by NR, suggesting that tubule tortuosity and/or tubule length was decreased in the NR kidney. Taken together the changes indicate that NR results in accelerated fetal renal differentiation. The negative impact of poor maternal nutrition on the fetal kidney may therefore be in part due to shortening of critical phases of renal growth resulting in decreased functional capacity in later life. These findings may have important implications for postnatal renal function, thereby contributing to the observed increased predisposition to hypertension and renal disease in the offspring of nutrient restricted mothers.

Baboons with high and low lipemic responses to dietary lipids differ in intestinal cholesterol absorption and hepatic cholesterol metabolism. ATP-binding cassette (ABC) transporters play an important role in cholesterol absorption and hepatic cholesterol metabolism. Using frozen tissues from high- and low-responding baboons maintained on the cholesterol and fat-enriched diet, we determined the relative expression of ABCA1, ABCG5, ABCG8, and 27-hydroxylase genes in the liver and intestine using TaqMan real-time polymerase chain reaction. There was no consistent difference in the expression of ABC-transporters and 27-hydroxylase in the intestine between high- and low-responding baboons. However, hepatic expression of sterol 27-hydroxylase, ABCG5, and ABCG8 was higher in low-responding baboons than in high-responding baboons. There was also a significant correlation between the expression of sterol 27-hydroxylase and ABCG5, and ABCG8 in both the liver and the intestine. These results suggest that differences in hepatic lipid metabolism but not in cholesterol absorption between high- and low-responding baboons observed previously may be mediated by the differences in the expression levels of 27-hydroxylase, ABCG5, and ABCG8.