Selected Grantee Publications
Western-Style Diet Consumption Impairs Maternal Insulin Sensitivity and Glucose Metabolism During Pregnancy in a Japanese Macaque Model
Elsakr et al., Scientific Reports. 2021.
https://www.nature.com/articles/s41598-021-92464-w
Using a Japanese macaque model, investigators assessed the metabolic effects of obesity and a calorically dense, Western-style diet (WSD; 36.3% fat), either alone or together, on maternal glucose tolerance and insulin levels in dams during pregnancy (n = 95 females followed over multiple pregnancies [n = 273]). With prolonged WSD feeding, multiple diet switches, and/or increasing age and parity, WSD was associated with increasingly higher insulin levels during glucose tolerance testing, indicative of insulin resistance. The results suggest that prolonged or recurrent calorically dense WSD and/or increased parity, rather than obesity per se, drive excess insulin resistance and metabolic dysfunction. Supported by ORIP (P51OD011092), NIDDK and NIMH.
Rhesus Macaques Build New Social Connections After a Natural Disaster
Testard et al., Current Biology. 2021.
https://www.sciencedirect.com/science/article/pii/S0960982221003687
Climate change has increased the frequency and intensity of weather-related disasters such as hurricanes and floods. In 2017, Puerto Rico suffered its worst natural disaster, Hurricane Maria, leaving 3,000 dead and provoking a mental health crisis. Cayo Santiago Island, home to a population of rhesus macaques (Macaca mulatta), was devastated by this storm. Testard et al. compared social networks of two groups of macaques before and after the hurricane and found an increase in affiliative social connections, driven largely by monkeys most socially isolated before Hurricane Maria. Further analysis revealed monkeys invested in building new relationships rather than strengthening existing ones. Supported by ORIP (P40OD012217), NIA, and NIMH.
A Novel Tau-Based Rhesus Monkey Model of Alzheimer’s Pathogenesis
Beckman et al., Alzheimer’s & Dementia. 2021.
https://pubmed.ncbi.nlm.nih.gov/33734581/
Alzheimer’s disease (AD) is becoming more prevalent as the population ages, but there are no effective treatments for this devastating condition. Researchers developed a rhesus monkey model of AD by targeting the entorhinal cortex with an adeno-associated virus expressing mutant tau protein. Within 3 months they observed evidence of misfolded tau propagation, similar to what is hypothesized for AD patients. Treated monkeys developed robust alterations in AD core biomarkers in cerebrospinal fluid and blood. These results highlight the initial stages of tau seeding and propagation in rhesus macaques, a potentially powerful translational model with which to test new AD therapies. Supported by ORIP (P51OD011107) and NIA.
Creb5 Establishes the Competence for Prg4 Expression in Articular Cartilage
Zhang et al., Communications Biology. 2021.
https://doi.org/10.1038/s42003-021-01857-0
Cells comprising the superficial zone of articular cartilage express lubricin, encoded by the Prg4 gene, that lubricates joints. Researchers identified Creb5 as a transcription factor that is required for TGF-β and EGFR signaling to induce Prg4 expression. Forced expression of Creb5 in deep-zone chondrocytes of articular cartilage confers competence for TGF-β and EGFR signals to induce Prg4 expression. The researchers showed that Creb5 directly binds to two Prg4 promoter-proximal regulatory elements, which work together with a more distal regulatory element to drive induction of Prg4 by TGF-β. Thus, Creb5 is a critical regulator of Prg4/lubricin expression in the articular cartilage. Supported by ORIP (U42OD11158), NIAMS, and NIDDK.
A Chromosome-Level Genome of Astyanax mexicanus Surface Fish for Comparing Population-Specific Genetic Differences Contributing to Trait Evolution
Warren et al., Nature Communications. 2021.
https://pubmed.ncbi.nlm.nih.gov/33664263/
Identifying the genetic factors that underlie complex traits is central to understanding the mechanistic underpinnings of evolution. Cave-dwelling Astyanax mexicanus populations are well adapted to subterranean life and many populations appear to have evolved troglomorphic (morphological adaptation of an animal to living in the constant darkness of caves) traits independently, while the surface-dwelling populations can be used as a proxy for the ancestral form. Warren et al. present a high-resolution, chromosome-level surface fish genome, enabling the first genome-wide comparison between surface fish and cavefish populations. Using this resource, they performed quantitative trait locus (QTL) mapping analyses and found new candidate genes for eye loss (dusp26). They also generated the first genome-wide evaluation of deletion variability across cavefish populations to gain insight into this potential source of cave adaptation. The surface fish genome reference now provides a more complete resource for comparative, functional and genetic studies of drastic trait differences within a species. Supported by ORIP (R24OD011198), NIA, NICHD, NIGMS, amd NIDCR.
Natural Killer Cells Activated Through NKG2D Mediate Lung Ischemia-Reperfusion Injury
Calabrese et al., Journal of Clinical Investigation. 2021.
https://www.jci.org/articles/view/137047
Pulmonary ischemia-reperfusion injury (IRI) causes early mortality and has no effective therapies. While natural killer (NK) cells are innate lymphocytes capable of recognizing injured cells, their roles in acute lung injury are incompletely understood. Here, investigators demonstrated that NK cells were increased in frequency and cytotoxicity in 2 different IRI mouse models. They showed that NK cells trafficked to the lung tissue from peripheral reservoirs and were more mature within lung tissue. Acute lung ischemia-reperfusion injury was blunted in a NK cell–deficient mouse strain but restored with adoptive transfer of NK cells. In human lung tissue, NK cells were increased at sites of ischemia-reperfusion injury and activated NK cells were increased in prospectively-collected human bronchoalveolar lavage in subjects with severe IRI. These data support a causal role for recipient peripheral NK cells in pulmonary IRI via NK cell NKG2D receptor ligation. Therapies targeting NK cells may hold promise in acute lung injury. Supported by ORIP (S10OD026940), NHLBI, and NIDDK.
Germline Transmission of Donor, Maternal and Paternal mtDNA in Primates
Ma et al., Human Reproduction. 2021.
https://doi.org/10.1016/j.immuni.2021.02.001
Mitochondrial gene mutations contribute to incurable human disorders. The possibility of using mitochondrial replacement therapy (MRT) to prevent transmission of pathogenic mitochondrial (mt)DNA was explored in rhesus macaques. Development of spindle MRT transfer in oocytes in 5 female rhesus macaques resulted in healthy and fertile offspring. These results demonstrate that MRT is compatible with normal postnatal development, including overall health and reproductive fitness in nonhuman primates with no detected adverse effects. Additional research is needed to more fully explore the use of MRT to prevent disorders as this study had a limited number of animals with only one female offspring. Supported by ORIP (P51OD0092) and NIA.
Lipocalin-2 Is an Anorexigenic Signal in Primates
Petropoulou et al., eLife. 2020.
https://doi.org/10.7554/eLife.58949
The hormone lipocalin-2 (LCN2) suppresses food intake in mice. Researchers demonstrated that LCN2 increases after a meal and reduces hunger in people with normal weight or overweight, but not in obese individuals. The researchers also showed that LCN2 crosses the blood-brain barrier and binds to the hypothalamus in vervet monkeys. LCN2 was found to bind to the hypothalamus in human, baboon, and rhesus macaque brain sections. When injected into vervets, LCN2 suppressed food intake and lowered body weight without toxic effects in short-term experiments. These findings lay the groundwork to investigate whether LCN2 might be a useful treatment for obesity. Supported by ORIP (P40OD010965), NCATS, NIDDK, NIA, and NHLBI.
Estrogen Acts Through Estrogen Receptor 2b to Regulate Hepatobiliary Fate During Vertebrate Development
Chaturantabut et al., Hepatology. 2020.
https://aasldpubs.onlinelibrary.wiley.com/doi/full/10.1002/hep.31184
During liver development, bipotent progenitor cells differentiate into hepatocytes and biliary epithelial cells to ensure a functional liver. The developmental cues controlling the differentiation of committed progenitors into these cell types are not completely understood. These authors report an essential role for estrogenic regulation in vertebrate liver development to affect hepatobiliary fate decisions. The studies identify17β-estradiol (E2), nuclear estrogen receptor 2b (esr2b), and downstream bone morphogenetic protein (BMP) activity as important regulators of hepatobiliary fate decisions during vertebrate liver development. These results have significant implications for liver development in infants exposed to abnormal estrogen levels or estrogenic compounds during pregnancy. Supported by ORIP (R24OD017870) and NIDDK.
Fructose Stimulated De Novo Lipogenesis Is Promoted by Inflammation
Jelena et al., Nature Metabolism. 2020.
https://pubmed.ncbi.nlm.nih.gov/32839596
Non-alcoholic fatty liver disease (NAFD) affects 30% of adult Americans. While NAFD starts as simple steatosis with little liver damage, its severe manifestation as non-alcoholic steatohepatitis (NASH) is a leading cause of liver failure, cirrhosis, and cancer. Fructose consumption is proposed to increase the risk of hepatosteatosis and NASH. Excessive intake of fructose causes barrier deterioration and low-grade endotoxemia. Using a mouse model, the study examined the mechanism of how fructose triggers these alterations and their roles in hepatosteatosis and NASH pathogenesis. The results demonstrated that microbiota-derived Toll-like receptor (TLR) agonists promote hepatosteatosis without affecting fructose-1-phosphate (F1P) and cytosolic acetyl-CoA. Activation of mucosal-regenerative gp130 signaling, administration of the YAP-induced matricellular protein CCN1 or expression of the antimicrobial peptide Reg3b (beta) counteract fructose-induced barrier deterioration, which depends on endoplasmic-reticulum stress and subsequent endotoxemia. Endotoxin engages TLR4 to trigger TNF production by liver macrophages, thereby inducing lipogenic enzymes that convert F1P and acetyl-CoA to fatty acid in both mouse and human hepatocytes. The finding may be of relevance to several common liver diseases and metabolic disorders. Supported by ORIP (S10OD020025), NCI, NIEHS, NIDDK, NIAID, and NIAAA.