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Campanile AA, Eckel LA, Keel PK. Elevated interleukin-6 in women with binge-eating spectrum disorders. Int J Eat Disord 2024; 57:1510-1517. [PMID: 38445571 PMCID: PMC11262979 DOI: 10.1002/eat.24183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 01/22/2024] [Accepted: 02/21/2024] [Indexed: 03/07/2024]
Abstract
OBJECTIVE Binge-eating spectrum disorders (BESD) involve large eating episodes accompanied by a sense of loss of control that occur in individuals with body weights spanning the full body mass index (BMI) spectrum. While research links BESD with peripheral inflammation, this literature is limited by underpowered studies and a failure to control for confounding variables that could promote inflammation independent of dysregulated eating, specifically elevated body adiposity and depression. Our study examined plasma interleukin-6 (IL-6), a marker of peripheral inflammation, in a sample of women with BESD and non-eating disorder controls, controlling for BMI, body adiposity, and depression. METHOD Participants (N = 94) included women with BESD (n = 73) or no eating disorder (n = 21) who completed structured clinical interviews in a larger study, selected to represent BMI categories ranging from underweight to obese in both groups. Fasting blood samples were processed for plasma IL-6 concentration via enzyme-linked immunosorbent assays. In addition to assessing group differences in plasma IL-6, exploratory analyses examined associations between IL-6 and biological and clinical markers of BESD. RESULTS Significantly elevated plasma IL-6 was found in women with BESD, relative to controls, that was not accounted for by BMI, adiposity, or depression. Plasma IL-6 was positively correlated with plasma leptin concentration, clinical assessments of eating disorder severity, and participants' largest self-reported eating episode. DISCUSSION Peripheral inflammation is specifically linked to presence of dysregulated eating independently from weight, adiposity, and depression in BESD. Future research should probe the potential role of neuroinflammation in altered eating behavior. PUBLIC SIGNIFICANCE This study provides the first demonstration that inflammation, characterized by elevated plasma IL-6 concentration, is uniquely associated with dysregulated eating in a transdiagnostic group of individuals with BESD. A better understanding of whether immune factors contribute to dysregulated eating could help identify novel biological targets for intervention.
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Affiliation(s)
- Alexis A. Campanile
- Division of Pharmacology and Toxicology, College of Pharmacy, University of Texas at Austin, Austin, Texas, USA
| | - Lisa A. Eckel
- Program in Neuroscience, Florida State University, Tallahassee, Florida, USA
- Department of Psychology, Florida State University, Tallahassee, Florida, USA
| | - Pamela K. Keel
- Department of Psychology, Florida State University, Tallahassee, Florida, USA
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2
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Lewis-Sanders D, Bullich S, Olvera MJ, Vo J, Hwang YS, Mizrachi E, Stern SA. Conditioned overconsumption is dependent on reinforcer type in lean, but not obese, mice. Appetite 2024; 198:107355. [PMID: 38621593 PMCID: PMC11308659 DOI: 10.1016/j.appet.2024.107355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/20/2024] [Accepted: 04/11/2024] [Indexed: 04/17/2024]
Abstract
Associative learning can drive many different types of behaviors, including food consumption. Previous studies have shown that cues paired with food delivery while mice are hungry will lead to increased consumption in the presence of those cues at later times. We previously showed that overconsumption can be driven in male mice by contextual cues, using chow pellets. Here we extended our findings by examining other parameters that may influence the outcome of context-conditioned overconsumption training. We found that the task worked equally well in males and females, and that palatable substances such as high-fat diet and Ensure chocolate milkshake supported learning and induced overconsumption. Surprisingly, mice did not overconsume when sucrose was used as the reinforcer during training, suggesting that nutritional content is a critical factor. Interestingly, we also observed that diet-induced obese mice did not learn the task. Overall, we find that context-conditioned overconsumption can be studied in lean male and female mice, and with multiple reinforcer types.
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Affiliation(s)
- Darielle Lewis-Sanders
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - Sebastien Bullich
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - Maria-Jose Olvera
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - John Vo
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - Yang-Sun Hwang
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - Elisa Mizrachi
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA
| | - Sarah A Stern
- Laboratory for Integrative Neural Circuits and Behavior, Max Planck Florida Institute for Neuroscience, 1 Max Planck Way, Jupiter, FL, 33458, USA.
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3
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Lewis-Sanders D, Bullich S, Olvera MJ, Vo J, Hwang YS, Stern SA. Conditioned overconsumption is dependent on reinforcer type in lean, but not obese, mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.31.573797. [PMID: 38260511 PMCID: PMC10802361 DOI: 10.1101/2023.12.31.573797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Associative learning can drive many different types of behaviors, including food consumption. Previous studies have shown that cues paired with food delivery while mice are hungry will lead increased consumption in the presence of those cues at later times. We previously showed that overconsumption can be driven in male mice by contextual cues, using chow pellets. Here we extended our findings by examining other parameters that may influence the outcome of context-conditioned overconsumption training. We found that the task worked equally well in males and females, and that palatable substances such as high-fat diet and Ensure chocolate milkshake supported learning and induced overconsumption. Surprisingly, mice did not overconsume when sucrose was used as the reinforcer during training, suggesting that nutritional content is a critical factor. Interestingly, we also observed that diet-induced obese mice did not learn the task. Overall, we find that context-conditioned overconsumption can be studied in lean males and female mice, and with multiple reinforcer types.
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Davis AB, Lloyd KR, Bollinger JL, Wohleb ES, Reyes TM. Adolescent high fat diet alters the transcriptional response of microglia in the prefrontal cortex in response to stressors in both male and female mice. Stress 2024; 27:2365864. [PMID: 38912878 PMCID: PMC11228993 DOI: 10.1080/10253890.2024.2365864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 05/28/2024] [Indexed: 06/25/2024] Open
Abstract
Both obesity and high fat diets (HFD) have been associated with an increase in inflammatory gene expression within the brain. Microglia play an important role in early cortical development and may be responsive to HFD, particularly during sensitive windows, such as adolescence. We hypothesized that HFD during adolescence would increase proinflammatory gene expression in microglia at baseline and potentiate the microglial stress response. Two stressors were examined, a physiological stressor [lipopolysaccharide (LPS), IP] and a psychological stressor [15 min restraint (RST)]. From 3 to 7 weeks of age, male and female mice were fed standard control diet (SC, 20% energy from fat) or HFD (60% energy from fat). On P49, 1 h before sacrifice, mice were randomly assigned to either stressor exposure or control conditions. Microglia from the frontal cortex were enriched using a Percoll density gradient and isolated via fluorescence-activated cell sorting (FACS), followed by RNA expression analysis of 30 genes (27 target genes, three housekeeping genes) using Fluidigm, a medium throughput qPCR platform. We found that adolescent HFD induced sex-specific transcriptional response in cortical microglia, both at baseline and in response to a stressor. Contrary to our hypothesis, adolescent HFD did not potentiate the transcriptional response to stressors in males, but rather in some cases, resulted in a blunted or absent response to the stressor. This was most apparent in males treated with LPS. However, in females, potentiation of the LPS response was observed for select proinflammatory genes, including Tnfa and Socs3. Further, HFD increased the expression of Itgam, Ikbkb, and Apoe in cortical microglia of both sexes, while adrenergic receptor expression (Adrb1 and Adra2a) was changed in response to stressor exposure with no effect of diet. These data identify classes of genes that are uniquely affected by adolescent exposure to HFD and different stressor modalities in males and females.
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Affiliation(s)
- Alyshia B Davis
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Kelsey R Lloyd
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Justin L Bollinger
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Eric S Wohleb
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Teresa M Reyes
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
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5
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Machado MMF, Ático EM, Banin RM, Hirata BKS, Kempe PRG, Pedroso AP, Thomaz FM, Oyama LM, Ribeiro EB, Bueno AA, Cerutti SM, Telles MM. Ginkgo biloba extract modulates astrocytic and microglial recruitment in the hippocampus and hypothalamus of menopause-induced ovariectomized rats. Brain Res 2023; 1822:148659. [PMID: 39492489 DOI: 10.1016/j.brainres.2023.148659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/05/2024]
Abstract
BACKGROUND Changes in steroid hormone levels associated with menopause are known to affect body composition, with increased accumulation of visceral fat and impaired actions of appetite-regulating neuropeptides. Anti-obesogenic, antioxidant, anti-inflammatory and neuromodulatory properties have been attributed to Ginkgo biloba extract (GbE) oral supplementation. HYPOTHESIS/PURPOSE We investigated in menopause-induced ovariectomized rats the effects of GbE oral supplementation on microglial reactivity and astrocyte recruitment in hippocampal and hypothalamic subregions involved in the regulation of feeding behavior and energy homeostasis. STUDY DESIGN/METHODS Ovariectomy (Ovx) or false-Ovx (Sham) surgery were performed in 2-month-old female Wistar rats. Sixty days after surgery, Ovx rats were gavaged daily for 14 days with either saline (Ovx + Veh) or GbE 500 mg/Kg (Ovx + GbE). Rats were subsequently sacrificed, brains harvested and subjected to immunohistochemistry and immunofluorescence analyses. RESULTS Ovx increased microglial reactivity in CA1, CA3 and dentate gyrus (DG) in the dorsal hippocampal formation (dHF), as well as in DG in the ventral hippocampal formation (vHF). Additionally, Ovx reduced astrocyte count in dHF CA3. The disturbances found in Ovx + Veh versus Sham were not found in Ovx + GbE versus Sham. Furthermore, higher astrocyte counts in DG of both dHF and vHF were found in Ovx + GbE as compared to Ovx + Veh. In the hypothalamus, Ovx + Veh showed reduced microglial reactivity in the arcuate (ARC) and ventromedial (VMH) nuclei as compared to Ovx + GbE. Ovx + GbE rats presented higher astrocyte counts in ARC compared to Sham rats. CONCLUSION Our results show for the first time in a rodent model of menopause that GbE supplementation modulates astrocyte and microglial recruitment and reactivity in hippocampal and hypothalamic subregions involved in feeding behavior and energy homeostasis. Future research employing other experimental models may further elucidate whether GbE supplementation possesses therapeutic properties upon glial cell reactivity to potentially alleviate changes in energy homeostasis associated with menopause.
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Affiliation(s)
- Meira M F Machado
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Esther M Ático
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Renata M Banin
- Discipline of Nutrition Physiology, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Bruna K S Hirata
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Paula R G Kempe
- Laboratory of Nerve Regeneration, Universidade de Campinas, Campinas, Brazil
| | - Amanda P Pedroso
- Discipline of Nutrition Physiology, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fernanda M Thomaz
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Lila M Oyama
- Discipline of Nutrition Physiology, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Eliane B Ribeiro
- Discipline of Nutrition Physiology, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Allain A Bueno
- College of Health, Life and Environmental Sciences, University of Worcester, Worcester WR2 6AJ, United Kingdom.
| | - Suzete M Cerutti
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil
| | - Mônica M Telles
- Post-graduate Program in Chemical Biology, Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo, Diadema, Brazil; Discipline of Nutrition Physiology, Department of Physiology, Universidade Federal de São Paulo, São Paulo, Brazil
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Muscat SM, Butler MJ, Mackey-Alfonso SE, Barrientos RM. Young adult and aged female rats are vulnerable to amygdala-dependent, but not hippocampus-dependent, memory impairment following short-term high-fat diet. Brain Res Bull 2023; 195:145-156. [PMID: 36870621 PMCID: PMC10257807 DOI: 10.1016/j.brainresbull.2023.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/18/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023]
Abstract
Global populations are increasingly consuming diets high in saturated fats and refined carbohydrates, and such diets have been well-associated with heightened inflammation and neurological dysfunction. Notably, older individuals are particularly vulnerable to the impact of unhealthy diet on cognition, even after a single meal, and pre-clinical rodent studies have demonstrated that short-term consumption of high-fat diet (HFD) induces marked increases in neuroinflammation and cognitive impairment. Unfortunately though, to date, most studies on the topic of nutrition and cognition, especially in aging, have been performed only in male rodents. This is especially concerning given that older females are more vulnerable to develop certain memory deficits and/or severe memory-related pathologies than males. Thus, the aim of the present study was to determine the extent to which short-term HFD consumption impacts memory function and neuroinflammation in female rats. Young adult (3 months) and aged (20-22 months) female rats were fed HFD for 3 days. Using contextual fear conditioning, we found that HFD had no effect on long-term contextual memory (hippocampus-dependent) at either age, but impaired long-term auditory-cued memory (amygdala-dependent) regardless of age. Gene expression of Il-1β was markedly dysregulated in the amygdala, but not hippocampus, of both young and aged rats after 3 days of HFD. Interestingly, modulation of IL-1 signaling via central administration of the IL-1 receptor antagonist (which we have previously demonstrated to be protective in males) had no impact on memory function following the HFD in females. Investigation of the memory-associated gene Pacap and its receptor Pac1r revealed differential effects of HFD on their expression in the hippocampus and amygdala. Specifically, HFD induced increased expression of Pacap and Pac1r in the hippocampus, whereas decreased Pacap was observed in the amygdala. Collectively, these data suggest that both young adult and aged female rats are vulnerable to amygdala-dependent (but not hippocampus-dependent) memory impairments following short-term HFD consumption, and identify potential mechanisms related to IL-1β and PACAP signaling in these differential effects. Notably, these findings are strikingly different than those previously reported in male rats using the same diet regimen and behavioral paradigms, and highlight the importance of examining potential sex differences in the context of neuroimmune-associated cognitive dysfunction.
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Affiliation(s)
- Stephanie M Muscat
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA; Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH, USA
| | - Michael J Butler
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - Sabrina E Mackey-Alfonso
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA; Medical Scientist Training Program, The Ohio State University, Columbus, OH, USA
| | - Ruth M Barrientos
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA; Department of Psychiatry and Behavioral Health, The Ohio State University, Columbus, OH, USA; Department of Neuroscience, The Ohio State University, Columbus, OH, USA; Chronic Brain Injury Program, The Ohio State University, Columbus, OH, USA.
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7
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Gaige S, Barbouche R, Barbot M, Boularand S, Dallaporta M, Abysique A, Troadec JD. Constitutively active microglial populations limit anorexia induced by the food contaminant deoxynivalenol. J Neuroinflammation 2022; 19:280. [PMID: 36403004 PMCID: PMC9675145 DOI: 10.1186/s12974-022-02631-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 10/26/2022] [Indexed: 11/21/2022] Open
Abstract
Microglia are involved in neuroinflammatory processes during diverse pathophysiological conditions. To date, the possible contribution of these cells to deoxynivalenol (DON)-induced brain inflammation and anorexia has not yet been evaluated. DON, one of the most abundant trichothecenes found in cereals, has been implicated in mycotoxicosis in both humans and farm animals. DON-induced toxicity is characterized by reduced food intake, weight gain, and immunological effects. We previously showed that exposure to DON induces an inflammatory response within the hypothalamus and dorsal vagal complex (DVC) which contributes to DON-induced anorexia. Here, in response to anorectic DON doses, we reported microglial activation within two circumventricular organs (CVOs), the area postrema (AP) and median eminence (ME) located in the DVC and the hypothalamus, respectively. Interestingly, this microglial activation was observed while DON-induced anorexia was ongoing (i.e., 3 and 6 h after DON administration). Next, we took advantage of pharmacological microglia deletion using PLX3397, a colony-stimulating factor 1 receptor (CSF1R)-inhibitor. Surprisingly, microglia-depleted mice exhibited an increased sensitivity to DON since non-anorectic DON doses reduced food intake in PLX3397-treated mice. Moreover, low DON doses induced c-Fos expression within feeding behavior-associated structures in PLX3397-treated mice but not in control mice. In parallel, we have highlighted heterogeneity in the phenotype of microglial cells present in and around the AP and ME of control animals. In these areas, microglial subpopulations expressed IBA1, TMEM119, CD11b and CD68 to varying degrees. In addition, a CD68 positive subpopulation showed, under resting conditions, a noticeable phagocytotic/endocytotic activity. We observed that DON strongly reduced CD68 in the hypothalamus and DVC. Finally, inactivation of constitutively active microglia by intraperitoneal administration of minocycline resulted in anorexia with a DON dose ineffective in control mice. Taken together, these results strongly suggest that various populations of microglial cells residing in and around the CVOs are maintained in a functionally active state even under physiological conditions. We propose that these microglial cell populations are attempting to protect the brain parenchyma from hazardous molecules coming from the blood. This study could contribute to a better understanding of how microglia respond to environmental contaminants.
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Affiliation(s)
- Stéphanie Gaige
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France
| | - Rym Barbouche
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France
| | - Manon Barbot
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France
| | - Sarah Boularand
- Aix-Marseille University, CNRS, Centrale Marseille, FSCM (FR1739), PRATIM, 13397, Marseille, France
| | - Michel Dallaporta
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France
| | - Anne Abysique
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France.
| | - Jean-Denis Troadec
- Aix-Marseille University, CNRS, Laboratoire de Neurosciences Cognitives, UMR 7291, 3 Place Victor Hugo, 13331, Marseille, France.
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Farhadi Z, Azizian H, Haji-Seyed-Javadi R, Khaksari M. A review: Effects of estrogen and estrogen receptor modulators on leptin resistance: Mechanisms and pathway. OBESITY MEDICINE 2022; 34:100446. [DOI: 10.1016/j.obmed.2022.100446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/07/2024]
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9
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Folick A, Cheang RT, Valdearcos M, Koliwad SK. Metabolic factors in the regulation of hypothalamic innate immune responses in obesity. Exp Mol Med 2022; 54:393-402. [PMID: 35474339 PMCID: PMC9076660 DOI: 10.1038/s12276-021-00666-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 05/13/2021] [Indexed: 12/14/2022] Open
Abstract
The hypothalamus is a central regulator of body weight and energy homeostasis. There is increasing evidence that innate immune activation in the mediobasal hypothalamus (MBH) is a key element in the pathogenesis of diet-induced obesity. Microglia, the resident immune cells in the brain parenchyma, have been shown to play roles in diverse aspects of brain function, including circuit refinement and synaptic pruning. As such, microglia have also been implicated in the development and progression of neurological diseases. Microglia express receptors for and are responsive to a wide variety of nutritional, hormonal, and immunological signals that modulate their distinct functions across different brain regions. We showed that microglia within the MBH sense and respond to a high-fat diet and regulate the function of hypothalamic neurons to promote food intake and obesity. Neurons, glia, and immune cells within the MBH are positioned to sense and respond to circulating signals that regulate their capacity to coordinate aspects of systemic energy metabolism. Here, we review the current knowledge of how these peripheral signals modulate the innate immune response in the MBH and enable microglia to regulate metabolic control.
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Affiliation(s)
- Andrew Folick
- Diabetes Center and Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Francisco, CA, USA
| | - Rachel T Cheang
- Diabetes Center and Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Francisco, CA, USA
| | - Martin Valdearcos
- Diabetes Center and Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Francisco, CA, USA.
| | - Suneil K Koliwad
- Diabetes Center and Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Francisco, CA, USA.
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10
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Glial Modulation of Energy Balance: The Dorsal Vagal Complex Is No Exception. Int J Mol Sci 2022; 23:ijms23020960. [PMID: 35055143 PMCID: PMC8779587 DOI: 10.3390/ijms23020960] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 02/04/2023] Open
Abstract
The avoidance of being overweight or obese is a daily challenge for a growing number of people. The growing proportion of people suffering from a nutritional imbalance in many parts of the world exemplifies this challenge and emphasizes the need for a better understanding of the mechanisms that regulate nutritional balance. Until recently, research on the central regulation of food intake primarily focused on neuronal signaling, with little attention paid to the role of glial cells. Over the last few decades, our understanding of glial cells has changed dramatically. These cells are increasingly regarded as important neuronal partners, contributing not just to cerebral homeostasis, but also to cerebral signaling. Our understanding of the central regulation of energy balance is part of this (r)evolution. Evidence is accumulating that glial cells play a dynamic role in the modulation of energy balance. In the present review, we summarize recent data indicating that the multifaceted glial compartment of the brainstem dorsal vagal complex (DVC) should be considered in research aimed at identifying feeding-related processes operating at this level.
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11
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Zhou J, Lin H, Xu P, Yao L, Xie Q, Mao L, Wang Y. Matcha green tea prevents obesity-induced hypothalamic inflammation via suppressing the JAK2/STAT3 signaling pathway. Food Funct 2021; 11:8987-8995. [PMID: 33001081 DOI: 10.1039/d0fo01500h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Obesity is an increasingly severe global health problem, leading to chronic inflammation and metabolic disorders in both peripheral tissues and the central nervous system. Matcha is a powdered green tea, and it is very popular in recent years as a beverage and food additive. Matcha green tea has been reported to have outstanding potential in regulating obesity-related metabolic syndrome. However, there are few studies on the regulation mechanism of matcha green tea on the central nervous system. In this study, we established a high-fat diet-induced obese mouse model. The results showed that dietary supplementation with matcha could effectively inhibit the weight gain, fat accumulation, glycemia and lipidemia increase, and excessive activation of microglia in the arcuate nucleus of the hypothalamus. Furthermore, we used different concentrations (100%, 80%, 60%, 40%, and 20%, v/v) of ethanol solution to prepare matcha ethanol extracts, and investigated their effects on palmitic acid-induced inflammation of microglial BV-2 cells. The results showed that matcha ethanol extracts could significantly reduce the release of inflammatory cytokines and the expression and phosphorylation of JAK2 and STAT3.
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Affiliation(s)
- Jihong Zhou
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
| | - Haiyu Lin
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
| | - Ping Xu
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
| | - Liyun Yao
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
| | - Qingyi Xie
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
| | - Limin Mao
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China. and Zhejiang Tea Group Co., Ltd, Hangzhou 310058, P. R. China
| | - Yuefei Wang
- Tea Research Institute, Zhejiang University, Zijingang Campus, Hangzhou 310058, P. R. China.
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12
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Alexaki VI. The Impact of Obesity on Microglial Function: Immune, Metabolic and Endocrine Perspectives. Cells 2021; 10:cells10071584. [PMID: 34201844 PMCID: PMC8307603 DOI: 10.3390/cells10071584] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 06/18/2021] [Accepted: 06/22/2021] [Indexed: 02/06/2023] Open
Abstract
Increased life expectancy in combination with modern life style and high prevalence of obesity are important risk factors for development of neurodegenerative diseases. Neuroinflammation is a feature of neurodegenerative diseases, and microglia, the innate immune cells of the brain, are central players in it. The present review discusses the effects of obesity, chronic peripheral inflammation and obesity-associated metabolic and endocrine perturbations, including insulin resistance, dyslipidemia and increased glucocorticoid levels, on microglial function.
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Affiliation(s)
- Vasileia Ismini Alexaki
- Institute for Clinical Chemistry and Laboratory Medicine, University Clinic Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany
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Lietzau G, Ntika S, Pintana H, Tracy L, Klein T, Nyström T, Darsalia V, Patrone C, Krizhanovskii C. A High-Fat Diet Increases Activation of the Glucagon-Like Peptide-1-Producing Neurons in the Nucleus Tractus Solitarii: an Effect that is Partially Reversed by Drugs Normalizing Glycemia. Cell Mol Neurobiol 2021; 42:1995-2002. [PMID: 33811589 PMCID: PMC9239971 DOI: 10.1007/s10571-021-01079-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/12/2021] [Indexed: 11/01/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is a peripheral incretin and centrally active peptide produced in the intestine and nucleus tractus solitarii (NTS), respectively. GLP-1 not only regulates metabolism but also improves cognition and is neuroprotective. While intestinal GLP-1-producing cells have been well characterized, less is known about GLP-1-producing neurons in NTS. We hypothesized that obesity-induced type 2 diabetes (T2D) impairs the function of NTS GLP-1-producing neurons and glycemia normalization counteracts this effect. We used immunohistochemistry/quantitative microscopy to investigate the number, potential atrophy, and activation (cFos-expression based) of NTS GLP-1-producing neurons, in non-diabetic versus obese/T2D mice (after 12 months of high-fat diet). NTS neuroinflammation was also assessed. The same parameters were quantified in obese/T2D mice treated from month 9 to 12 with two unrelated anti-hyperglycemic drugs: the dipeptidyl peptidase-4 inhibitor linagliptin and the sulfonylurea glimepiride. We show no effect of T2D on the number and volume but increased activation of NTS GLP-1-producing neurons. This effect was partially normalized by both anti-diabetic treatments, concurrent with decreased neuroinflammation. Increased activation of NTS GLP-1-producing neurons could represent an aberrant metabolic demand in T2D/obesity, attenuated by glycemia normalization. Whether this effect represents a pathophysiological process preceding GLP-1 signaling impairment in the CNS, remains to be investigated.
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Affiliation(s)
- Grazyna Lietzau
- Department of Clinical Science and Education, Karolinska Institutet, Sodersjukhuset Internal Medicine, 118 83, Stockholm, Sweden. .,Faculty of Medicine, Department of Anatomy and Neurobiology, Medical University of Gdansk, Gdansk, Poland.
| | - Stelia Ntika
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.,Department of Research, Södertälje Hospital, Södertälje, Sweden
| | - Hiranya Pintana
- Department of Clinical Science and Education, Karolinska Institutet, Sodersjukhuset Internal Medicine, 118 83, Stockholm, Sweden
| | - Linda Tracy
- Department of Research, Södertälje Hospital, Södertälje, Sweden
| | - Thomas Klein
- Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany
| | - Thomas Nyström
- Department of Clinical Science and Education, Karolinska Institutet, Sodersjukhuset Internal Medicine, 118 83, Stockholm, Sweden
| | - Vladimer Darsalia
- Department of Clinical Science and Education, Karolinska Institutet, Sodersjukhuset Internal Medicine, 118 83, Stockholm, Sweden
| | - Cesare Patrone
- Department of Clinical Science and Education, Karolinska Institutet, Sodersjukhuset Internal Medicine, 118 83, Stockholm, Sweden
| | - Camilla Krizhanovskii
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden. .,Department of Research, Södertälje Hospital, Södertälje, Sweden.
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14
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Evolution of the Human Diet and Its Impact on Gut Microbiota, Immune Responses, and Brain Health. Nutrients 2021; 13:nu13010196. [PMID: 33435203 PMCID: PMC7826636 DOI: 10.3390/nu13010196] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/30/2020] [Accepted: 01/07/2021] [Indexed: 12/18/2022] Open
Abstract
The relatively rapid shift from consuming preagricultural wild foods for thousands of years, to consuming postindustrial semi-processed and ultra-processed foods endemic of the Western world less than 200 years ago did not allow for evolutionary adaptation of the commensal microbial species that inhabit the human gastrointestinal (GI) tract, and this has significantly impacted gut health. The human gut microbiota, the diverse and dynamic population of microbes, has been demonstrated to have extensive and important interactions with the digestive, immune, and nervous systems. Western diet-induced dysbiosis of the gut microbiota has been shown to negatively impact human digestive physiology, to have pathogenic effects on the immune system, and, in turn, cause exaggerated neuroinflammation. Given the tremendous amount of evidence linking neuroinflammation with neural dysfunction, it is no surprise that the Western diet has been implicated in the development of many diseases and disorders of the brain, including memory impairments, neurodegenerative disorders, and depression. In this review, we discuss each of these concepts to understand how what we eat can lead to cognitive and psychiatric diseases.
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Thadathil N, Xiao J, Hori R, Alway SE, Khan MM. Brain Selective Estrogen Treatment Protects Dopaminergic Neurons and Preserves Behavioral Function in MPTP-induced Mouse Model of Parkinson's Disease. J Neuroimmune Pharmacol 2020; 16:667-678. [PMID: 33221984 DOI: 10.1007/s11481-020-09972-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 11/16/2020] [Indexed: 12/20/2022]
Abstract
Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra and loss of both motor and non-motor features. Several clinical and preclinical studies have provided evidence that estrogen therapy reduces the risk of PD but have limitations in terms of adverse peripheral effects. Therefore, we examined the potential beneficial effects of the brain-selective estrogen prodrug, 10β, 17β-dihydroxyestra-1,4-dien-3-one (DHED) on nigrostriatal dopaminergic neurodegeneration and behavioral abnormalities in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Wild-type mice were treated with daily subcutaneous injections of DHED (50 and 100 µg/kg) or vehicle for four weeks. To produce PD-like symptoms, mice were injected with MPTP (18 mg/kg in saline; intraperitoneally) four times at 2-hr intervals for one day. After behavioral examination, mice were sacrificed, and the brains were isolated for neurochemical and morphological examinations. MPTP injected mice exhibited loss of dopaminergic neurons and fibers in substantia nigra and striatum respectively, along with impaired motor function at day 7 post MPTP injection. These phenotypes were associated with significantly increased oxidative stress and inflammatory responses in the striatum regions. DHED treatments significantly mitigated behavioral impairments and dopaminergic neurodegeneration induced by MPTP. We further observed that DHED treatment suppressed oxidative stress and inflammation in the striatum of MPTP treated mice when compared to vehicle treated mice. In conclusions, our findings suggest that DHED protects dopaminergic neurons from MPTP toxicity in mouse model of PD and support a beneficial effect of brain-selective estrogen in attenuating neurodegeneration and motor symptoms in PD-related neurological disorders. Graphical Abstract.
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Affiliation(s)
- Nidheesh Thadathil
- Department of Neurology, College of Medicine, University of Tennessee Health Science Center, 855 Monroe Avenue, 415 Link Building, Memphis, TN, 38163, USA
| | - Jianfeng Xiao
- Department of Neurology, College of Medicine, University of Tennessee Health Science Center, 855 Monroe Avenue, 415 Link Building, Memphis, TN, 38163, USA
| | - Roderick Hori
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Stephen E Alway
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
- Center for Muscle, Metabolism and Neuropathology, Division of Rehabilitation Sciences, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Mohammad Moshahid Khan
- Department of Neurology, College of Medicine, University of Tennessee Health Science Center, 855 Monroe Avenue, 415 Link Building, Memphis, TN, 38163, USA.
- Center for Muscle, Metabolism and Neuropathology, Division of Rehabilitation Sciences, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN, USA.
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16
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Butler MJ, Cole RM, Deems NP, Belury MA, Barrientos RM. Fatty food, fatty acids, and microglial priming in the adult and aged hippocampus and amygdala. Brain Behav Immun 2020; 89:145-158. [PMID: 32544595 PMCID: PMC7572563 DOI: 10.1016/j.bbi.2020.06.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/20/2020] [Accepted: 06/06/2020] [Indexed: 02/08/2023] Open
Abstract
Short-term (3-day) consumption of a high fat diet (HFD) rich in saturated fats is associated with a neuroinflammatory response and subsequent cognitive impairment in aged, but not young adult, male rats. This exaggerated effect in aged rats could be due to a "primed" microglial phenotype observed in the normal aging process in rodents in which aged microglia display a potentiated response to immune challenge. Here, we investigated the impact of HFD on microglial priming and lipid composition in the hippocampus and amygdala of young and aged rats. Furthermore, we investigated the microglial response to palmitate, the main saturated fatty acid (SFA) found in HFD that is proinflammatory. Our results indicate that HFD increased gene expression of microglial markers of activation indicative of microglial priming, including CD11b, MHCII, CX3CR1, and NLRP3, as well as the pro-inflammatory marker IL-1β in both hippocampus and amygdala-derived microglia. Furthermore, HFD increased the concentration of SFAs and decreased the concentration of polyunsaturated fatty acids (PUFAs) in the hippocampus. We also observed a specific decrease in the anti-inflammatory PUFA docosahexaenoic acid (DHA) in the hippocampus and amygdala of aged rats. In a separate cohort of young and aged animals, isolated microglia from the hippocampus and amygdala exposed to palmitate in vitro induced an inflammatory gene expression profile mimicking the effects of HFD in vivo. These data suggest that palmitate may be a critical nutritional signal from the HFD that is directly involved in hippocampal and amygdalar inflammation. Interestingly, microglial activation markers were increased in response to HFD or palmitate in an age-independent manner, suggesting that HFD sensitivity of microglia, under these experimental conditions, is not the sole mediator of the exaggerated inflammatory response observed in whole tissue extracts from aged HFD-fed rats.
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Affiliation(s)
- Michael J. Butler
- Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH, USA
| | - Rachel M. Cole
- Department of Human Sciences, Ohio State University, Columbus, OH, USA
| | - Nicholas P. Deems
- Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH, USA
| | - Martha A. Belury
- Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH, USA,Department of Human Sciences, Ohio State University, Columbus, OH, USA
| | - Ruth M. Barrientos
- Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH, USA,Department of Psychiatry and Behavioral Health, Ohio State University, Columbus, OH, USA,Department of Neuroscience, The Ohio State University, Columbus, OH, USA,Chronic Brain Injury Program, Discovery Themes Initiative, The Ohio State University, Columbus, OH, USA,Corresponding author: Dr. Ruth M. Barrientos, Institute for Behavioral Medicine Research and Department of Psychiatry and Behavioral Health, Ohio State University, 460 Medical Center Drive, Columbus, OH 43210, Tel.: 614-293-6591,
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Christensen A, Liu J, Pike CJ. Aging Reduces Estradiol Protection Against Neural but Not Metabolic Effects of Obesity in Female 3xTg-AD Mice. Front Aging Neurosci 2020; 12:113. [PMID: 32431604 PMCID: PMC7214793 DOI: 10.3389/fnagi.2020.00113] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/03/2020] [Indexed: 12/29/2022] Open
Abstract
Vulnerability to Alzheimer's disease (AD) is increased by several risk factors, including midlife obesity, female sex, and the depletion of estrogens in women as a consequence of menopause. Conversely, estrogen-based hormone therapies have been linked with protection from age-related increases in adiposity and dementia risk, although treatment efficacy appears to be affected by the age of initiation. Potential interactions between obesity, AD, aging, and estrogen treatment are likely to have significant impact on optimizing the use of hormone therapies in postmenopausal women. In the current study, we compared how treatment with the primary estrogen, 17β-estradiol (E2), affects levels of AD-like neuropathology, behavioral impairment, and other neural and systemic effects of preexisting diet-induced obesity in female 3xTg-AD mice. Importantly, experiments were conducted at chronological ages associated with both the early and late stages of reproductive senescence. We observed that E2 treatment was generally associated with significantly improved metabolic outcomes, including reductions in body weight, adiposity, and leptin, across both age groups. Conversely, neural benefits of E2 in obese mice, including decreased β-amyloid burden, improved behavioral performance, and reduced microglial activation, were observed only in the early aging group. These results are consistent with the perspective that neural benefits of estrogen-based therapies require initiation of treatment during early rather than later phases of reproductive aging. Further, the discordance between E2 protection against systemic versus neural effects of obesity across age groups suggests that pathways other than general metabolic function, perhaps including reduced microglial activation, contribute to the mechanism(s) of the observed E2 actions. These findings reinforce the potential systemic and neural benefits of estrogen therapies against obesity, while also highlighting the critical role of aging as a mediator of estrogens' protective actions.
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Affiliation(s)
| | | | - Christian J. Pike
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, United States
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