bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rax Expression Identifies a Novel Cell Type in the Adult Mouse Hypothalamus
Authors: Wittmann Gabor , Gahlot Surbhi , Low Malcolm James , Lechan Ronald M 
Published: May 2021

Abstract
Hypothalamic tanycytes are radial glia-like ependymal cells lining the ventrolateral walls and floor of the third ventricle. Recent data show that tanycytes are adult neural stem/progenitor cells, capable of generating neurons that populate the adjacent hypothalamic nuclei involved in the regulation of feeding and energy balance. Thus, the genetic fate mapping of tanycytes has become an invaluable tool to identify and study tanycyte-derived adult-born hypothalamic neurons. Perhaps the most selective tanycyte marker identified to date is the retina and anterior neural fold homeobox (Rax), that has been used as a tanycyte marker in multiple single-cell transcriptomic studies. By using in situ hybridization and immunofluorescence, we show that Rax mRNA and RAX protein are also expressed in a minor but significant population of parenchymal cells that are concentrated in the caudal arcuate nucleus. RAX-positive nuclei in the parenchyma were often observed in pairs, suggesting recent cell divisions. The morphology of these cells was studied in tamoxifen-treated Rax-CreERT2; Ai34(RCL-Syp/tdT)-D mice, in which the synaptophysin-tdTomato fusion protein permanently labels Rax-expressing cells and their progeny. While some parenchymal RAX-positive cells had tanycyte-like morphology indicative of tanycyte migration into the parenchyma, the majority had a very different morphology with extensive local processes that often encircled adjacent neurons (termed “frizzy cells”). The tdTomato labeling also revealed numerous frizzy cells that were negative for RAX, indicating downregulation of endogenous Rax expression subsequent to the induction of synaptophysin-tdTomato reporter expression. Many of these cells were distributed outside the caudal arcuate nucleus, including the rostral lateral arcuate nucleus, ventromedial and dorsomedial hypothalamic nuclei and lateral hypothalamus. RAX-negative frizzy cells were also conspicuous in the paraventricular nucleus, and occasionally observed in the preoptic region and bed nucleus of the stria terminalis. Frizzy cells were negative for the tanycyte-enriched proteins vimentin, monocarboxylate transporter 8 (MCT8) or glial fibrillary acidic protein (GFAP). These results identify a novel Rax-expressing cell type in the adult hypothalamus that differs from tanycytes in location, morphology and gene expression characteristics. Future studies are required to determine whether frizzy cells are derived from tanycytes or constitute a separate cell lineage, and whether they represent a migratory form of neural precursor cells in the adult hypothalamus.
Environmental Enrichment Potentiates Glucose-Induced Anorexia in Mice
Authors: Aldhshan Muhammad , Mizuno Tooru 
Published: May 2021

Abstract
The hypothalamus controls food intake and metabolism by integrating nutrient and hormonal signals from peripheral tissues. Both central and peripheral administration of glucose leads to a reduction in food intake in rodents. Similarly, administration of the adipocyte hormone leptin or the gastrointestinal hormone xenin reduces food intake. In contrast, impairments in hypothalamic signaling of these factors cause hyperphagia and obesity in rodents and humans. Environmental factors affect behavior including feeding behavior and energy metabolism in rodents and humans. Studies have found that environmental enrichment (EE), in which mice interact with complex sensory and motor stimulation, led to a significant reduction in adiposity and resistance to diet-induced obesity in mice. This effect is independent of energy expenditure and is associated with enhanced hypothalamic signaling, but the exact mechanism is unknown. We hypothesized that EE potentiates the feeding suppressing effects of anorectic signals. To address this hypothesis, 4-week-old male C57BL/6 mice were group housed (5/cage) under standard laboratory conditions or EE conditions with free access to regular rodent chow and feeding response to glucose, leptin and xenin was examined. EE cages were supplemented with a house, running wheels, igloos, wood logs, maze and nesting materials. Four weeks after initiating EE protocol, mice were fasted for 8 h and received an intraperitoneal injection of glucose (2 mg/g b.w.) or saline just before the onset of the dark phase. Treatment assignments were reversed for the second injection so that each animal received both treatments with a washout period of 1 week. Mice were given food immediately after the injection and food intake was measured for 4 h after the injection at 0.5–1 h intervals. The same design was repeated using leptin (2.5 μg/g b.w.) and xenin (15 or 50 μg/g b.w.). Glucose injection caused a significant reduction of food intake in both control and EE mice. However, anorexic effect of glucose was more significant in EE group compared to the control group (main effect of treatment: P = 0.0016 for control and P &lt; 0.0001 for EE, two-way ANOVA). Significant reductions in food intake were observed between 0.5 and 2.5 h after glucose injection in EE mice, while no significant reduction was observed thereafter. Moreover, three-way ANOVA showed a significant interaction between housing condition and treatment (P = 0.0086). In contrast, although both leptin and xenin caused a significant reduction in food intake, there was no significant interaction between housing condition and treatment. These data suggest that environmental enrichment enhances the anorectic action of glucose without altering feeding response to leptin and xenin. It is speculated that enhanced hypothalamic glucose sensing may mediate beneficial effects of environmental enrichment on metabolism.
Functional Interaction of Spexin and Adiponectin Forming a Local Feedbackin Goldfish Hepatocytes for Feeding Regulation
Authors: Zheng Yunhua , Bai Jin , He Mulan , Wong Anderson O L 
Published: May 2021

Abstract
Spexin (SPX), a neuropeptide with pleiotropic functions, has been confirmed to be a novel satiety factor in fish models. Adiponectin (AdipoQ), the most abundant adipokine in circulation, is involved in lipid and glucose metabolism and its insulin-sensitizing, cardioprotective, and anti-inflammatory actions are also well-documented. However, the interaction between SPX and AdipoQ has not be reported and very little is known regarding the functions of AdipoQ in non-mammalian species. In this study, AdipoQ was cloned in goldfish and found to be widely expressed at tissue level including the liver. Sequence alignment and in silico protein modelling revealed that its a.a. sequence and 3D protein structure were highly comparable to the mammalian counterparts. Recombinant protein of goldfish AdipoQ was expressed in E. coli and IP injection of the protein purified could suppress foraging activity and food intake in goldfish. Food intake in goldfish, interestingly, could elevate plasma levels of SPX and AdipoQ with parallel rises of their transcript expression in the liver. In primary culture of goldfish hepatocytes, SPX treatment was shown to induce protein phosphorylation of MEK1/2 and ERK1/2 with a parallel rise in AdipoQ mRNA level. SPX-induced AdipoQ mRNA expression, however, was sensitive to the blockade of PLC/PKC, Ca2+/CaMK-II and MEK1/2/ERK1/2 but not cAMP/PKA cascades. In reciprocal experiments, AdipoQ treatment could induce protein phosphorylation of AMPK, Akt and P38 MAPK in goldfish hepatocytes. Meanwhile, AdipoQ was also effective in reducing SPX mRNA level and this inhibitory effect was negated by blocking the AMPK/PPAR, PI3K/Akt and P38 MAPK but not the MEK1/2/ERK1/2 or PLC/PKC pathways. Apparently, the PI3K/Akt and P38 MAPK cascades were functionally coupled with AMPK activation. These results imply that (i) AdipoQ, similar to SPX, can be induced by food intake and serve as a satiety signal in goldfish, (ii) AdipoQ expression in goldfish liver can be up-regulated by SPX via the PLC/PKC, Ca2+/CaMK-II and MEK1/2/ERK1/2 pathways, which may enhance the satiation response caused by SPX after food intake, and (iii) AdipoQ can inhibit SPX expression at hepatic level via the AMPK/PPAR, PI3K/Akt and P38 MAPK cascades, which may lead to signal termination of SPX. These findings, as a whole, suggest that AdipoQ production in goldfish liver not only can form a signal amplification step for the satiation response of SPX but also constitute a local feedback to turn off SPX signal at the hepatic level.
Hepatic Expression of the Mouse Angptl8 Gene Is Regulated by Insulin Through Increases in Hepatocyte Nuclear Factor-1
Authors: Watanabe Takuya , Watanabe Takuya , Ozawa Atsushi , Kondo Yuri , Horiguchi Kazuhiko , Nakajima Yasuyo , Okada Shuichi , Yamada Masanobu 
Published: May 2021

Abstract
Angiopoietin-like proteins (ANGPTLs) are a family of proteins structurally similar to angiopoietins. ANGPTL8 is an important regulator of circulating triglyceride (TG) levels in mammals. Increasing evidence revealed an association between ANGPTL8 expression and serum lipid profiles, especially in subjects with metabolic syndrome. Several mice studies demonstrated that Angptl8 is suppressed by fasting and induced by long term refeeding, however the detailed mechanism is still unclear. In humans, ANGPTL8 is mainly expressed in the liver. Therefore, this study aims to investigate the mechanisms that control the refeeding induced increase in the hepatic Angptl8 gene expression. Methods and Results: Twenty-week-old male C57/BL6 mice were used in this study. Mice were fasted for 12h during the dark cycle and re-fed for 30, 60, 120, 240 and 360 minutes during the light cycle. Mice were euthanized after each refeeding time course and tissues were collected. We found even short refeeding times (~60 min) enhanced the expression levels of hepatic Angptl8 in mice. We cloned the mouse Angptl8 gene promoter region. Promoter deletion analyses showed that the basal promoter activity was significantly attenuated by a deletion of -309/-60 region in hepatocytes. A computational motif search revealed the presence of a potential binding motif for hepatocyte nuclear factor 1α/1β (HNF-1α/β) at -84/-68 bp of the promoter. Mutations of the HNF-1 binging site significantly decreased the promoter activity in mouse hepatoma cells (Hepa1-6) and mouse primary hepatocytes, and the promoter carrying the mutated HNF-1 site was not transactivated by co-transfected HNF-1 in a non-hepatic cell line. These findings indicated that HNF-1 was essential and critical factor for the basal expression of Angptl8 in murine liver. In fact, knockdown of Hnf-1 using siRNA method in mouse Hepa1-6 and mouse primary hepatocytes reduced Angptl8 protein levels. We also performed Electrophoretic mobility-shift assays and confirmed the direct binding of Hnf-1 to its Angptl8 promoter binding motif. To elucidate whether refeeding could enhance HNF-1, we checked the expression levels of Hnf-1 in mouse liver. Hnf-1 expression levels of both mRNA and protein were increased after short-term refeeding, paralleling the enhanced expression of the Angptl8. Moreover, insulin-stimulated primary hepatocytes showed increased expression of Angptl8 protein, but knockdown of Hnf-1 completely abolished this enhancement by insulin. Chromatin immunoprecipitation (ChIP) analyses confirmed the recruitment of endogenous Hnf-1 to the Angptl8 promoter region and it was strongly induced by insulin. Conclusion: HNF-1 plays essential role in hepatocyte-specific and refeeding-induced rapid increases in Angptl8 expression via insulin.
Hypothalamic Glucagon Receptors Regulate Feeding in Mice
Authors: Cunningham Stephen E , Nason Shelly R , Presedo Natalie , Kim Teayoun , Antipenko Jessica , DiMarchi Richard D , Habegger Kirk M 
Published: May 2021

Abstract
Glucagon is an essential regulator of glucose and lipid metabolism. We have reported that chronic glucagon receptor (GCGR) activation with the highly selective, long-acting GCGR-agonist, IUB288, promotes weight-loss by stimulating energy expenditure and suppressing food intake in diet-induced obese (DIO) mice. Thus, novel therapeutics that include glucagon receptor (GCGR) agonism have emerged as promising candidates for obesity and diabetes. GCGR-stimulated energy expenditure is predominately dependent on hepatic GCGR activation; however, the tissue(s) responsible for GCGR-dependent suppression of food intake have yet to be elucidated. Intriguingly, intracerebroventricularly (ICV) injected glucagon acutely suppresses food intake, suggesting neurons expressing GCGR in the brain mediate the anorectic actions of GCGR activation. Hypothalamic neurons express appetitive neuropeptides, sense nutrients in circulation, and respond to peripheral endocrine signals. Studies herein, utilize mice with hypothalamic Gcgr-deficiency (GcgrΔHypo) to test the hypothesis that peripherally administered GCGR-agonists (e.g. IUB288) reverse obesity via their actions on hypothalamic GCGRs to suppress food intake and concurrent hepatic effects on energy expenditure. GcgrΔHypo and littermate control mice were fasted overnight to stimulate endogenous hunger signals and test for differential food intake upon refeeding. Interestingly, lean, male GcgrΔHypo mice displayed acute hyperphagia in comparison to control littermates. GcgrΔHypo mice also displayed elevated locomotor activity, an increase in the respiratory exchange ratio, and elevated energy expenditure compared to littermate controls. Furthermore, these metabolic alterations are associated with delayed body weight gain and chronic hyperphagia in GcgrΔHypo mice allowed ad libitum access to a high fat diet for 12 weeks. Consistent with our hypothesis, chronic peripheral administration of IUB288 (14d i.p.) suppressed food intake in DIO male control, but not GcgrΔHypo, mice. Altogether, these data suggest that hypothalamic GCGRs mediate the anorectic actions of GCGR activation and play a regulatory role in food take. Moreover, these findings suggest that GCGR-based therapeutics may act on both intake and expenditure components of energy balance to combat obesity.
Identifying a New Mechanism of Sarcopenia by Autophagy
Authors: Yamada Eijiro , Uehara Ryota , Nakajima Yasuyo , Horiguchi Kazuhiko , Ishida Emi , Matsumoto Shunichi , Okada Shunichi , Yamada Masanobu 
Published: May 2021

Abstract
Sarcopenia is one of the critical factors in reducing Activity of Daily Life and associated with morbidity and mortality. Sarcopenia has also been linked to metabolic syndrome. In recent years, it has been reported that autophagy is one of the mechanisms as a cause of sarcopenia. Therefore, we focused on autophagy as a system that can regulate both sarcopenia and metabolic syndrome in skeletal muscle and revealed that non-receptor tyrosine kinase Fyn not only participates in metabolic syndrome but also regulates autophagy regulating sarcopenia through STAT3 regulation, mainly using transgenic mice (Cell metabolism 2010, Cell Rep. 2012). However, since these were non-physiological studies, we proceeded with further studies and demonstrating that Fyn dependent STAT3 phosphorylation by IL6, which is involved in chronic inflammation and metabolic syndrome, was observed in mouse C2C12 myotube cells. Autophagy was decreased in those cells by both IL6 dependent and Fyn dependent mechanisms. Furthermore, in the denervated mouse model, not only both Fyn and IL6 gene expressions as well as the key muscle specific E3 ubiquitin ligases, Atrogin1 and MuRf1 were increased but the expression and phosphorylation levels of STAT3 were also augmented, while the autophagy activity was decreased. We believe that a denervated mouse model alone is not enough as a model for sarcopenia, thus we next introduced a hind limb suspension mouse model that promotes disuse atrophy by suspending the hind limb. Using this model, we found that muscle atrophy was observed mainly in the soleus muscle, tibialis anterior muscle, and the gastrocnemius muscle with Atrogin1 and MuRf1 increased. Increase of both IL6 and STAT3 expression/phosphorylation were also observed in the muscles of hind limb suspension mice. Autophagy activity, examined by intraperitoneal administration of colchicine, was decreased. These results strongly suggest that Fyn is involved not only in the metabolic syndrome but also in the pathogenesis of sarcopenia, and may lead to a better understanding of the pathology of sarcopenia obesity and the development of therapeutic methods.
PFOA Exposure Prior to Hepatocyte Differentiation Leads to Gene Expression Changes Implicated in Non-Alcoholic Fatty Liver Disease
Authors: Hanke Stephanie , Joshi Apoorva , Fu Weixuan , Wang Paul , Tarapore Pheruza , Simmons Rebecca Anne , Pinney Sara Elizabeth 
Published: May 2021

Abstract
Background: Perfluorooctanoic acid (PFOA), is a persistent fluorinated compound with oil and water repelling properties found in cookware, food packaging and municipal water systems. Adult animals exposed to PFOA develop hepatomegaly, fatty liver, peroxisome proliferation, and immunotoxicity. Rodents exposed to PFCs in utero have altered hepatic lipid metabolism, increased hepatic de novo lipogenesis and susceptibility to non-alcoholic fatty liver disease (NAFLD), but underlying molecular mechanisms remain unknown. With increasing rates of obesity, diabetes, and NAFLD it is critical to examine the mechanisms by which in utero exposure to PFOA contributes to the development of metabolic syndrome in offspring. Objective: To determine mechanism by which PFOA alters gene expression in undifferentiated hepatic progenitor cells. Design/methods: HepaRG cells, a human derived hepatocyte progenitor cell line, was treated with 0.5uM PFOA or vehicle for 48 hours followed by differentiation into hepatocytes. Total RNA was extracted using the RNeasy (Qiagen) [total RNA A260/280&gt;2 and RNA integrity number &gt;7 (Agilent Bioanalyzer)] to generate libraries with the Illumina TruSeq stranded total RNA kit. RNA-Seq was performed using 85 bp single-end read sequencing to generate &gt;20 million reads per sample. RNAseq data was aligned to hg38 using STAR v2.6.1a and then quantified with featureCounts v1.6.2. DESeq2 identified differentially expressed genes via FDR (false discovery rate) after Bonferroni correction. Differentially expressed gene lists were used for Ingenuity Pathway Analysis (IPA) to identify pathways of biological significance.
Results: PFOA treatment resulted in increased expression of transcription factors EGR1 (early growth response protein 1), NR4A1 (nuclear receptor Nur77), EGR2 (early growth response protein 2), KLF10 (Krueppel-like factor 10) and FOSL1 (Fos-related antigen 1), key genes linked to impaired hepatic insulin signaling, hepatic lipid metabolism, steatosis and fibrosis (fold change &gt; 1.5; q &lt;0.05). IPA identified enrichment of canonical pathways with biological relevance including hepatic fibrosis signaling, stellate cell activation, VDR/RXR/TR activation, and Type 2 diabetes mellitus signaling (p&lt;0.01). Conclusion: Hepatocyte progenitor cells exposed to low dose PFOA for 48 hours prior to differentiation results in changes in expression of key metabolic genes linked to the development of NAFLD and enrichment of biologically relevant pathways associated with hepatic fibrosis and hepatocellular carcinoma. These results suggest that PFOA exposure in utero may have lasting effects on hepatic glucose and lipid metabolism after differentiation. Further studies are needed to characterize the longstanding metabolic effects of in utero PFOA exposure in offspring and the mechanisms driving the persistence of these changes.
TLANDO, a Novel Oral TRT, Improves Sexual and Mental Domain Outcomes in Hypogonadal Men
Authors: Bruno Benjamin J , Vangara Kiran , Kim Kilyoung , Papangkorn Kongnara , Chidambaram Nachiappan , Patel Mahesh V , DelConte Anthony , Carson III Culley C , Goldstein Irwin , Kaminetsky Jed , Miner Martin , Khera Mohit 
Published: May 2021

Abstract
Male hypogonadism is characterized by symptoms and deficiency (&lt;300 ng/dL) in levels of in total testosterone (TT), a critical hormone for sexual, cognitive, and body function and development. TLANDO, a testosterone undecanoate (TU) comprising lymphatically delivered oral testosterone replacement therapy (TRT) option not requiring dose titration, treatment has demonstrated effective restoration in hypogonadal men of TT levels to the eugonadal range in multiple clinical studies. TLANDO therapy resulted in decreased sex hormone binding globulin with increased free testosterone (FT). TLANDO’s unique delivery system enables consistent restoration of TT regardless of meal fat content. Moreover, TLANDO has shown potential to improve liver health through resolution of fatty liver disease in hypogonadal men and is not known to have any adverse liver effects. However, it is unclear if fixed dose TLANDO therapy without dose adjustment improves symptoms of psychosexual functions. The objective is to assess key sexual and mental domain Patient Reported Outcomes (PRO) post 52 weeks of treatment using TLANDO on the to-be-marketed dosing regimen in comparison with a widely used topical TRT, Androgel 1.62%. Data analysis was performed in in hypogonadal males post TLANDO treatment without dose adjustment, and in patients on the active control from a randomized, multi-center, open label, active controlled 52-week trial (SOAR, NCT02081300). Sexual and mental domain function PROs were measured at baseline (BL) and end of study (EOS) using Psychosexual Daily Questionnaire (PDQ) and Short Form (SF)-36 surveys and compared between TLANDO and active control. Post treatment with TLANDO dosing regimen not requiring dose titration, key sexual domain function PROs at week 52 were significantly (p&lt;0.05) improved from BL: positive mood (BL:4.5 vs EOS:5.1, p&lt;0.001), negative mood (1.8 vs 1.4, p&lt;0.01), overall sexual desire (2.5 vs 3.7, p&lt;0.001), sexual activity (2.5 vs 4.0, p&lt;0.001), highest pleasure with partner (2.0 vs 2.8, p=0.06), highest pleasure without partner (1.8 vs 2.4, p&lt;0.05), weekly maintained erection (3.3 vs 4.5, p&lt;0.001), and weekly full erection % (50.5% vs 68.9%, p&lt;0.001). Most sexual and mental function PROs were comparable to Androgel 1.62. TLANDO therapy was well tolerated through 52 weeks of treatment exposure. In conclusion, TLANDO, a novel easy to use and prescribe TRT not requiring dose titration, demonstrated improvement in sexual and mental PROs, a significant unmet need in hypogonadal males. Further placebo-controlled studies are warranted to better elucidate these improvements.