bluuebunny/crossref_metadata_2025_split huggingface dataset:
Angiotensin II‐ mediated vasoconstriction of the visceral adipose tissue vasculature is linked to systemic hypertension in obesity
Authors: Park Song‐Young , Karki Shakun , Saggese Samantha M. , Zuriaga Maria A. , Carmine Brian , Hess Donald , Apovian Caroline , Gokce Noyan 
Published: November 2023

ObjectivesCentral adiposity, in particular the accumulation of intra‐abdominal visceral fat, has been linked to adipose tissue dysfunction and obesity‐related diseases including hypertension and atherosclerosis, however regulatory mechanisms are poorly understood. We hypothesized that increased micro‐vascular tone specifically in visceral fat may contribute to abnormal peripheral vascular resistance.MethodsIn 30 obese subjects(age 42±10 yr, BMI 42±3 kg/m2) undergoing elective bariatric surgery, we characterized vaso‐contractile responses of isolated subcutaneous (SC) and visceral (VIS) adipose tissue arterioles using videomicroscopy, and examined relevant depot‐specific gene expression using qPCR.ResultsVisceral arterioles exhibited significantly greater angiotensin II‐mediated vasoconstriction by 20% in obese hypertensives (OH, SBP 146±8 mmHg) compared to obese normotensives (O, SBP 118±5 mmHg) (p<0.05). Additionally, VIS arterioles showed greater vasoconstriction in response to angiotensin II compared to SC in OH (by 25%, p<0.05) but not in O. Angiotensin converting enzyme (ACE) mRNA expression was significantly increased in VIS compared to SC (2‐fold, p<0.05) in OH but not O. In contrast, vasopressor responses to other agonists including endothelin‐1 and phenylephrine were not different between fat depots or subjects with or without hypertension.ConclusionThe findings demonstrate differential activation of the renin‐angiotensin system (RAS) in the visceral adipose tissue microvasculature that may contribute to mechanisms of systemic hypertension in obesity. RAS targeting, in particular, may provide incremental clinical benefit in treating obesity‐related hypertension.Support or Funding InformationNIH grants P01HL081587 and RO1 HL1145675
Neural Stem Cells Reduce Symptomatic Inflammation and Mortality in Aged Stroke Mice following Delayed tPA Treatment
Authors: Eckert Auston D. , Hamblin Milton , Lee Jean‐Pyo 
Published: November 2023

Stem cell therapy offers great promise in treating stroke. Extensive injury from stroke results from ischemia‐reperfusion (IR), which damages the blood‐brain barrier (BBB), promotes inflammation and loss of cerebral parenchyma. Presently, tissue plasminogen activator (tPA) is the sole FDA‐approved antithrombotic treatment available for stroke. tPA has a narrow time window (<4.5hour) and delayed tPA (>5h) can exacerbate BBB damage and increase hemorrhagic complications. Our long‐term goal is to limit early‐stage BBB injuries, an outcome that would protect against the second phase of stroke damage. Aging is a strong risk factor for stroke but the harmful effects of delayed tPA (>4.5h), particularly on aged stroke animals, have not been well studied. We utilized a mouse model of stroke with middle cerebral artery occlusion (MCAO) to induce focal ischemia followed by reperfusion. We injected human neural stem cells (hNSCs) 24h after MCAO to correspond to the upregulation of endogenous proinflammatory cytokines. Previously, we reported that intracranial transplantation of hNSCs rapidly ameliorates BBB damage caused by ischemic stroke in young adult mice. In this study, we employed aged mice to test the effect of delayed tPA‐induced IR injury. We tested the hypothesis that hNSCs ameliorate pathophysiology of aged stroke mice after delayed tPA administration (6h post‐MCAO). We found that delayed tPA administration exacerbates BBB damage, upregulates inflammatory cytokines, and increases mortality. Engrafted hNSCs reduced BBB disruption, rapidly ameliorated symptomatic inflammation, and decreased mortality within 24h post‐transplantation (48h post‐MCAO). Our data demonstrate clear benefits of hNSCs during the early stage of ischemic stroke in aged stroke mice.Support or Funding Information1. Louisiana Clinical and Translational Science Center (LA CaTs), Pilot Grant, to J‐P. L. 2. Carol Lavin Bernick Faculty Grant to J‐P. L, Tulane University.
Interferon type II increases lipolysis and fatty acid oxidation in pancreatic β cells
Authors: Truong Nguyen , Bazil Jason , Olson L. Karl 
Published: November 2023

Type 1 diabetes (T1D) is characterized by loss of insulin‐secreting β cells in the pancreas due to autoimmune attack by reactive lymphocytes, which can be triggered by viral infection. Proinflammatory cytokines, including interferons, are secreted by immune cells and have been implicated in pathogenesis of T1D. While interferon type II (IFNγ) has been shown to affect β cell insulin survival, its role on β cell metabolism and anti‐viral response remains to be investigated. In this study, we found that acute treatment of rat insulinoma cells (INS‐1) and Wistar rat islets with IFNγ (12 hours) induced expression of adipose triglyceride lipase (ATGL) mRNA and protein, the major enzyme that contributes to triacylglyceride (TAG) lipolysis. The increased expression of ATGL by IFNγ was associated with increased fatty acid oxidation and upregulation of genes involving in this process. Pharmacological inhibition of carnitinepalmitoyltransferase 1A (CPT1A), the rate‐limiting step of mitochondrial fatty acid oxidation, resulted in a substantial reduction in oxygen consumption rate in IFNγ‐treated INS‐1 cells. In contrast, genes that regulate lipogenesis and triglyceride synthesis were not affected by IFNγ treatment. Lipoprotein lipase (LPL) expression was suppressed, indicating a possible reduction in exogenous fatty acid delivery. These changes in lipid metabolism are concomitant with robust increase in expression of genes that involve in inflammation (STATs and NOS2), anti‐viral response (PKR, MxA), recruitment of immune cells (CXCL10) and a slight increase in endoplasmic reticulum stress markers (CHOP, ATFs). These data suggest that upon acute inflammation, pancreatic beta cell responds to IFNγ by alternating lipid metabolism flux, i.e. increasing lipolysis and fatty acid oxidation, which ultimately increase ATP production through oxidation of intracellular TAG. This change in metabolism may benefit the anti‐viral and anti‐inflammatory response of β cell in the early stage of β cell autoimmunity.Support or Funding InformationJDRF 3‐SRA‐2014‐43‐Q‐R
Estradiol Receptor Agonists α and β Protect Against Brain Mitochondrial Dysfunction in a Model of Sleep Apnea
Authors: Laouafa Sofien , Bairam Aida , Soliz Jorge , Roussel Damien , Joseph Vincent 
Published: November 2023

We tested the hypothesis that intermittent hypoxia (IH) induces a mitochondrial dysfunction in the brain of adult female rats, and that agonists of α and β estradiol receptors (ER) protect against this effect. Female rats were ovariectomized (OVX) and implanted with an osmotic pump continuously delivering vehicle (OVX‐Veh), PPT (OVX‐PPT – ERα agonist ‐ 30μg/kg/day) or DPN (OVX‐DPN ‐ ERβ agonist ‐ 100μg/kg/day). Two weeks later, the animals were exposed to intermittent hypoxia (IH‐21–10% O2 – 10 cycles/hour – 8 hours/day – 7 days) or room air (RA). We then used fresh brain cortex tissue (~2 mg) permeabilized with saponin to assess mitochondrial functions with high‐resolution respirometry (O2k‐Oroboros). With substrates of complex I (Pyruvate/Glutamate/Malate) and in presence of ADP, rats exposed to IH have a reduced O2 consumption compared to RA rats (55±7 vs 88±4 pmol O2/s/mg tissue, p<0.0001). PPT and DPN treatments prevented this alteration (O2 consumption being respectively 104±6 and 90±6 pmolO2/s/mg, p<0.0001 vs OVX‐IH rats). With the substrate of complex II (succinate) and ADP, there was no effect of IH, but O2 consumption was higher in OVX‐PPT rats compared to OVX‐IH rats. With the substrates of complexes I+II and ADP, O2 consumption was reduced by IH exposure compared to RA (51±9 vs 87±12 pmol O2/s/mg, p<0.0001), and this was partially prevented by DPN (68±10, p<0.03 vs OVX‐IH), while OVX‐PPT rats had the highest O2 consumption (125±11 pmolO2/s/mg, p<0.0001 vs OVX‐IH and OVX‐RA). H2O2 production measured by fluorometry with the substrates of complexes I+II and ADP is increased by exposure to IH compared to RA (3.2 ±0.4 vs 0.9±0.3 pmol H2O2/min/mg– p=0.002), and this is prevented by DPN and PPT (1.8 ±0.2 vs 1.6±0.2 pmol H2O2/min/mg).We conclude that in OVX female rats, IH impairs the mitochondrial respiratory chain through the complex I leading to an increase of ROS (H2O2) production. Selective agonists of ERα and ERβ prevent the mitochondrial dysfunction. ERα appears more efficient to increase mitochondrial respiratory function in this model. This opens new perspectives for menopausal women suffering of sleep apnea.Support or Funding InformationFounded by CIHR, Région Rhône alpes and consulat de France à Québec.
Duality of Early Life Maternal Separation Effects on Offspring Initial Development and Maternal Neuronal Activation
Authors: Fóscolo Daniela Rocha Costa , Machado Frederico Sander Mansur , Coimbra Cândido Celso 
Published: November 2023

BackgroundEarly life experiences induce behavioral and neuronal changes on most mammals, including humans. Maternal separation during the initial stages of biological development engender different modifications not only to the offspring, but also to the mother. Previously, we have shown that 2 weeks of daily episodes of maternal separation during the neonatal period, changed brain activity in response to stressful stimuli. Therefore, we investigated whether the same protocol of maternal separation evoked changes in neuronal phenotype and activity in the hypothalamus of matrices. In parallel, pups' growth and development were evaluated until adulthood.Materials and methodsMaternal separation started at the 2nd day after delivery and consisted in taking the mother out of the cage for 180 min/day until the 14th day of life. Weaning happened on the 30th day of life and the animals were monitored until the 180th day. Matrices were euthanized on days 2, 14 and 30 in order to access expression of c‐fos in vasopressin and/or oxytocin neurons in the anterior hypothalamus. Offspring was sacrificed after 180 days of life in order to evaluate metabolic parameters such as leptin, insulin, glucose and triglycerides.ResultsOur results shown that 14 days of maternal separation modifies both the expression and c‐fos activity of oxytocin and vasopressin neurons in the PVN and SON. These modifications in the matrices persisted until the 30th day after delivery, but only in the PVN. In parallel, after 180 days of life, the offspring showed increased mesenteric fat, insulin resistance and leptin levels.ConclusionOur data points towards prolonged side effects of maternal separation on offspring metabolism during adulthood. Interestingly, the effect of maternal separation on the mother occurred at the hypothalamic level persisting until weaning at least. These results confirms the duality of effects elicited by maternal separation, both on the offspring and the mother.Support or Funding InformationCAPES, CNPq, FAPEMIG and PRPq/UFMG
Structural Analysis of Inner Ear Hair Cell Mitochondria Near the Striated Organelle
Authors: Lesus Joseph , Perkins Guy , Lysakowski Anna 
Published: November 2023

Mitochondria are important organelles found in every cell of the body. The current depiction of a mitochondrion, containing an inner membrane (IM), outer membrane and cristae that increase the surface area of the IM, has been the universally accepted model for decades. Although the basic function and structure of mitochondria have been studied, careful analysis of electron microscopy data has led to the identification of structurally different subpopulations of mitochondria in the inner ear (Lysakowski and Goldberg, JCN, 1997). There are several known mitochondrial‐related deafness and vestibular disorders, such as dizziness, vertigo and nystagmus (Iwasaki et al., Laryng, 2011). In order to further characterize inner ear mitochondrial subpopulations and relate them to these diseases, we used IMOD software to create 3D models of mitochondria located near different energy‐demanding cellular components. From these models, we collect quantitative data, such as crista surface area and volume and whole mitochondrion values. With these data, we can approximate a mitochondrion's energy output. The main structure of interest in this study was the striated organelle (SO), a cytoskeletal structure found in the apicolateral region of hair cells (Vranceanu et al., PNAS, 2012). We expected that mitochondria near the SO would have a fairly large energy output. It was hypothesized that there would be more points on the IM that joined with cristae membranes, the so‐called “crista junctions” (Rabl et al., JCB, 2009; Zick et al., BBA, 2009) on the side facing the striated organelle (Perkins et al., JNS, 2010). In the future, models of the different subpopulations can be compared structurally, which can lead to an explanation of differences in physiology or sensitivity to noxious agents. Exploring these differences should lead to determining the population of mitochondria affected in mitochondrial‐related deafness or vestibular disorders.Support or Funding InformationSupported by NIH R21‐DC013181 (AL) and P41‐RR004050 (GP, ME).
Identification of the Neurotransmitter Substance P in Sural Nerve of Rats: An Immunohistochemistry Approach
Authors: Giorgetto Carolina , Simoes Ana Leda Bertoncini , Fazan Valeria Paula Sassoli 
Published: November 2023

The sural nerve in rats is mainly sensory, providing innervation for the lateral side of the hind paws [1]. The substance P (SP) is a neurotensmitter known to be present in small myelinated and unmyelinated fibers, being closely related to pain tranmission to the central nervous system [2]. Thus, the presence of SP is expected in small fibers of the sural nerves. Nevertheless, morphological demonstration of the presence of SP in sural nerves of rats were not yet performed by immunohistochemestry (IHC). We developed an IHC protocol to identify the SP in sural nerve of male and female Wistar‐Kyoto rats. The animals were anesthetized and had the sural and phrenic nerves (positive control) surgically removed, immersed in Karnovsky solution (4% paraformaldehyde, 2% glutaraldehyde) and cryoprotected in solutions of sucrose with increasing concentrations. Transversal cryosections (18μm) of the nerves were incubated in rabbit polyclonal antibody anti‐substance P (1:10.000, 24h), followed by biotinylated anti‐rabbit IgG (1:500; 24h) and finally Extravidin‐HRP (1:1500, 24h). A reaction with diaminobenzidine intensified with nickel revealed immunoreactivity by light microscopy, confirming the effectiveness and viability of the IHC technique proposed by our protocol for identification of the SP in sural nerve. These results indicate the possibility of investigating neurotransmitter contents in different fiber pupulations in normal nerves and their correlation with peripheral neuropathies such as diabetes and hypertension.Support or Funding InformationFAPESP, CNPq, CAPES and FAEPA
Antioxidant and Anti‐proliferative Activity of Fractions from Anona senegalensis Pers (Annonaceae) Stem Bark on HeLa Cells
Authors: Adisa Rahmat Adetutu , Getti Giulia T.M , Richardson Simon C.W 
Published: November 2023

Anona Senegalensis Pers (Annonaceae) parts are used locally for herbal therapy, food and aesthetics. There is no scientific record of its anticancer activity on HeLa cells. The aim of the present study was to investigate the antioxidant, cytotoxic and apoptotic properties of the ethanol extracts of Anona senegalensis and its fractions on HeLa cancer cells. The HeLa cells were incubated for 24, 48 and 72 h with different concentrations of fractions of Anona senegalensis for cell viability using the MTT assay. Apoptotic cells were determined by DNA fragmentation and PE‐Annexin V assay using flow cytometry. Phytochemical screening of the ethanol extracts revealed the presence of tannin, saponin, phenol, flavonoid, alkaloid, terpenoids, reducing sugar and cardiac glycosides. Increasing concentrations of the fractions inhibited lipid peroxidation and DPPH radical scavenging activity in a dose‐dependent manner by at least 65% at 100 μg/mL. Furthermore, ethanol, hexane, aqueous, ethylacetate and chloroform fractions inhibited HeLa cells viability to different extent in a concentration‐dependent manner over the incubation periods. The IC50 values of ethanol, chloroform, hexane, ethylacetate, and aqueous fractions were 235.2, 24.3, 245, 1625.3, and 156.2μg/mL, respectively after 24h. These extract fractions caused apoptosis as shown by DNA fragmentation. Treatment of HeLa cells with the chloroform fraction induced the release of cytochrome C. The results indicate that Anona senegalensis possess strong antioxidant property and anti‐proliferative activity. The chloroform fraction is the most cytotoxic and the mechanism of anti‐proliferative activity involves apoptosis via the mitochondrial pathway through the release of cytochrome c from the mitochondria.Support or Funding InformationFederal Republic of Nigeria Tertiary Education Fund (TETFUND) for Academic Staff Training & Development ‐ 2014
Synthesis and Antibacterial Activity of Novel Semi‐Synthetic Triterpenoids
Authors: Da Silva Gabriela Jorge , Pereira Manuela , Da Salvador Jorge 
Published: November 2023

Emergence of antimicrobial resistance has become a critical public health concern worldwide. Novel antimicrobials are urgently needed, and plants with therapeutic properties constitute a rich source of biologically active compounds. Triterpenoids are a class of compounds found widely distributed in nature and have shown diverse biological activity, including anti‐tumoral activity. Structure‐activity studies have revealed that alterations in key carbons may enhance biological activity and reduce cytotoxicity. Little is known of the antibacterial activity of olealonic (OA) and ursolic (UA) acids. Moreover, the antibacterial activity of modified triterpene pentacyclic structures has yet to be characterized.AIMThe objective of this study was to synthesize derivatives of olealonic (OA) and ursolic (UA) acids, and to test them against the antibiotic susceptible Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212 strains, and methicillin‐resistant S. aureus and vancomycin‐resistant E. faecalis of clinical origin.METHODS and RESULTSInitially, OA, UA, and 14 semi‐synthetic derivatives were screened for antibacterial activity by the disk diffusion method. Minimum inhibitory concentrations (MIC) were determined by microdilution method. MICs ranged from 62.5 to 125 ug/mL in Gram negative bacteria, from 31.3 to 125 ug/mL for S. aureus strains and from 7.8 to 125 ug/mL for E. faecalis. In general, UA and compound 14, a derivative of UA, showed the best activity against Gram positive bacteria. No significant differences in MICs were observed between the antibiotic susceptible and resistant clinical strains. Both compounds reduced the bacterial growth of S. aureus ATCC 29213 and E. faecalis ATCC 29212 in the presence of 0,5xMIC, MIC, 2xMIC relatively to the control, more significant in the latter. MTT cytotoxicity assays revealed that compound 14 did not induce significant cell toxicity in macrophages (RAW 264.7), with 84% viability at concentrations delivering effective (MIC). Overall, the compounds tested showed a better antimicrobial activity against Gram‐positive bacteria.CONCLUSIONThe data indicate that compound 14 may offer a new avenue for the development of new antimicrobials with reduced cytotoxicity. This work also illustrates that modifications of the natural molecule and the study of structure‐activity relationship is crucial to unravel new biological activity.
Scavenger Receptor BI Mediates the Uptake and Transcytosis of HDL in Brain Microvascular Endothelial Cells Independent of PDZK1 and Nitric Oxide
Authors: Fung Karen Yin Yue , Wang Changsen , Nyegaard Steffen , Heit Bryan , Fairn Gregory , Lee Warren 
Published: November 2023

The vascular endothelium supplying the brain exhibits very low paracellular and transcellular permeability which protects the brain from fluctuations in ion concentrations and exposure to circulating toxins. The blood‐brain‐barrier (BBB) consists in large part of a continuous monolayer of endothelial cells joined by intercellular tight junctions that effectively occlude the intercellular space, reducing paracellular permeability. At the same time, the impermeability of the blood‐brain barrier is not absolute, allowing the regulated transport of various molecules such as high‐density lipoprotein (HDL). HDL crosses the blood‐brain barrier by transcytosis but technical limitations have made it difficult to elucidate its regulation. Elucidating the mechanisms of HDL transcytosis across the blood‐brain barrier, in particular, may be significant pathologically as its constituent apolipoprotein ApoAI has been demonstrated to confer a protective effect against Alzheimer disease (AD). Using a combination of spinning‐disc confocal and total internal reflection fluorescence microscopy, we examined the internalization and transcytosis of fluorescently labeled HDL by human primary brain microvascular endothelial cell monolayers. Using these approaches, we report that HDL internalization requires dynamin but not clathrin heavy chain and that its internalization and transcytosis are saturable. Internalized HDL partially co‐localized with the scavenger receptor BI (SR‐BI) and knockdown of SR‐BI significantly attenuated HDL internalization. However, we observed that the adaptor protein PDZK1 ‐ which is critical to HDL‐SR‐BI signaling in other tissues ‐ is not required for HDL uptake in these cells. Furthermore, inhibition of endothelial nitric oxide synthase did not prevent HDL transcytosis but increased HDL internalization while the addition of exogenous nitric oxide had no effect on internalization. Together, these data indicate that HDL transcytosis across the blood‐brain barrier involves a non‐canonical signaling pathway downstream of SR‐BI. Our findings may facilitate manipulation of HDL transcytosis to increase delivery of ApoA1 as a potential therapeutic approach for AD and to increase transport of HDL‐like synthetic particles containing therapeutic drug across the blood‐brain barrier to treat neurodegenerative diseases.Support or Funding InformationKaren Fung ‐ Ontario Early Researchers Award from Dr. Gregory Fairn