bluuebunny/crossref_metadata_2025 huggingface dataset:
Prediction of child health and nutrient intake by child versus parent reports of child food insecurity
Authors: Choi Seul Ki , Frongillo Edward A , Fram Maryah S
Published: June 2021

Recent qualitative studies reported that children experience food insecurity differently than adults, and that parents often do not have knowledge of their child's experiences. We investigated if children's reports of their own food insecurity more accurately predict child health and nutrient intake than parent reports of child food insecurity. Using data from the 2005–2008 National Health and Nutrition Examination Survey, we analyzed child food insecurity reported by 820 children aged 12–17 years and their parents in food‐insecure households in relation to child self‐reported health and nutrient intakes reported by children from 1–2 days of 24‐h recall. Five similar items were used for child and parent reports of child food insecurity. Agreement between child and parent reports was poor (Kappa: −0.01–0.07). Child food insecurity was reported by 31.8% of parents and by 26.0% of children. Compared with food‐secure children, food‐insecure children reported by child had significantly poorer health and less vitamin A, riboflavin, niacin, folate, vitamin B12, calcium, and iron intakes; those as reported by the parent had significantly poorer health and less thiamin, folate, and iron intakes. Child reports more accurately predicted poor health than parent reports (p=0.031). These results imply that child reports of food insecurity capture adverse effects of child food insecurity better than parent reports.
Food insecurity is associated with dietary intake and diet quality of low‐income adults
Authors: Leung Cindy W , Epel Elissa S , Ritchie Lorrene D , Crawford Patricia B , Laraia Barbara A
Published: June 2021

Food insecurity has been linked with poor physical health among adults. Using 1999–2008 NHANES data, we examined associations between food insecurity and dietary intake and diet quality among 8,098 low‐income nonelderly adults with household incomes ≤300% of the federal poverty level. Usual dietary intake was estimated with 1–2 24‐hour recalls using the National Cancer Institute method. After controlling for sociodemographic characteristics, very low food security was associated with consuming fewer servings of fruits (Relative Difference (RD)=0.93, 95% CI 0.87, 1.00), vegetables (RD=0.93, 95% CI 0.90, 0.97, P‐trend=0.004), and white potatoes (RD=0.93, 95% CI 0.89, 0.97, P‐trend<0.001), and more servings of red and processed meat (RD=1.06, 95% CI 1.02, 1.10, P‐trend=0.01), high‐fat dairy (RD=1.13, 95% CI 1.06, 1.20, P‐trend<0.001), and sugar‐sweetened beverages (RD=1.12, 95% CI 1.04, 1.21, P‐trend= 0.006). No differences were observed for total energy and macronutrients; few differences were observed for micronutrients. Very low food security was also associated with a 4% lower Healthy Eating Index‐2005 scores (95% CI −4%, −4%, P‐trend< 0.001) and a 5% lower Alternate Healthy Eating Index‐2010 scores (95% CI −5%, −5%, P‐trend<0.001). These results suggest that food insecurity is adversely associated with diet quality among low‐income adults.
Compound K, a Panax ginseng saponin, inhibits lipid accumulation during adipocyte differentiation by regulating early adipogenic genes
Authors: Jeon Hui‐Jeon , Choi Hyeon‐Son
Published: June 2021

Compound K (20‐O‐β‐(D‐glucopyranosyl)‐20 (S)‐protopanaxadiol, CK) is one of the major panaxadiol ginsenosides in Panax ginseng. CK has been known to have various biological properties such as anti‐inflammation, anti‐diabetes and anti‐tumor. In this study, we investigated anti‐adipogenic effect of CK during adipogenesis in 3T3‐L1 cell. CK suppressed lipid accumulation during adipogenesis in a dose‐dependent manner (10, 25, 50 μM) in Oil red O staining assay. This inhibition was evidenced by the downregulation of triacylglycerol synthetic proteins such as Glycerol‐3‐ phosphate acyltransferase3 (GPAT3), 1‐acylglycerol‐3‐phosphate acyltransferase2 (AGPAT2), Lipin1 and Diacylglycerol acyltransferase1 (DGAT1). Our data also showed that the inhibitory action of CK was usually limited to early stage of adipogenesis. This result was correlated to the reduction in mRNA levels of the early adipogenic factors, Krueppel‐like factor4 (KLF4), Early growth response2 (EGR2), CCAAT/enhancer‐binding protein beta (C/EBPβ), and C/EBPδ. In contrast, mRNA expression of a negative regulator of early adipogenesis, KLF2, was increased with a CK treatment. CK‐induced regulation of early adipogenic genes led to the reduction in the expression of the late adipogenic transcription factors such as peroxisome proliferator activated receptor gamma (PPARγ) and C/EBPα, and their target gene, Fatty acid binding protein4 (FABP4). Collectively, our study suggests that CK is an inhibitory edible compound on adipogenesis and TG synthesis.

Grant Funding Source: Korea and National Research Foundation of Korea
Plant sterol whole body pool size in sitosterolemia is modulated by ezetimibe
Authors: Othman Rgia Ali , Myrie Semone B , Mymin David , Merkens Louise , Roullet Jean‐Baptiste , Steiner Robert D , Jones Peter J.H.
Published: June 2021

Sitosterolemia (STSL) is a sterol storage disorder characterized by very high plasma plant sterols levels. Ezetimibe (EZE), a sterol‐absorption inhibitor, has been shown to reduce plasma plant sterol levels in STSL. However, its effect on whole body sitosterol pool (WBSP) has not been well characterized. The study aimed to measure WBSP size in STSL, off and on EZE. STSL patients (pts, n=8) were taken off EZE for 14 wks. After 4 wks off EZE, they received an IV dose of D7‐sitosterol (1 mg/kg BW), and blood samples were serially collected over 10 wks. Afterward, pts resumed EZE therapy and the experiment repeated. D7‐sitosterol enrichment was measured by liquid chromatography‐tandem mass spectrometry and plasma sterols by gas chromatography. Data (mean±SEM ) were analyzed using paired t‐test. EZE reduced plasma sitosterol by 35% (5.1±0.5 vs 7.8±0.6 mg/dl; P<0.05), and WBSP by 53% compared with off treatment (106.1±15.5 vs 226.8±73.4 mg/kg BW; P=0.05) at 5 wks. Plasma cholesterol concentrations tended to decrease with EZE but not significantly (153.8±10.7 vs 178.3±13.9 mg/dl; P=0.09). Decline in WBSP was positively correlated with plasma sitosterol levels(r=0.58, p<0.05). These results indicated that plasma plant sterols, but not cholesterol levels were significantly reduced by EZE, suggesting plant sterol abnormality rather than cholesterol. Thus, EZE may work by reducing WBSP size in STSL pts. Funded by NIH and CIHR

Grant Funding Source: NIH and CIHR
High‐fat diet alters serum fatty acid profiles in obesity prone rats: implications for in‐vitro studies
Authors: Liu Tzu‐Wen , Heden Timothy D. , Blandon Abiezer , Morris E. Matthew , Fritsche Kevin L. , Thyfault John P.
Published: June 2021

High‐fat diet (HFD) feeding is commonly used in animal models to induce obesity and metabolic diseases. However, the effect of HFD on serum fatty acid profiles remains unclear. Changes in serum fatty acid profiles due to HFD may be a factor in lipotoxicity in various organs. Historically, in vitro studies have utilized individual non‐esterified fatty acids (NEFA) to study lipid exposure, potentially ignoring the importance of fatty acid combinations on cellular lipid metabolism.

OBJECTIVE

To create a physiological relevant fatty acid mixture to investigate lipid exposure in a cell culture system.

METHODS

Obesity prone rats were fed a HFD (60% en fat) or a control diet (10% en fat) for 2 weeks; portal and systemic blood samples were collected. Triglycerides (TG) and NEFA were extracted and analyzed using gas chromatography.

RESULTS

Both systemic and portal serum TG were ~40% lower in HFD. In the control, monounsaturated fatty acids (MUFAs) were the predominant fatty acids in serum TG, whereas polyunsaturated fatty acids (PUFAs) were the dominant fatty acids in the HFD group. Serum NEFA levels were not affected by diet.

CONCLUSION

HFD alters serum fatty acid composition of TG from one where MUFAs predominant to PUFAs in rats. A more physiologically relevant fatty acid mixture to mimic HFD conditions for in vitro studies may include increased PUFAs relative to saturated fatty acids and MUFAs. Support: R01DK088940 (JPT)
Establishment and induction of arterial and venous identities in human iPSC derived vascular endothelial cells
Authors: Adams William James , Zhang Yuzhi , Garcia‐Cardena Guillermo
Published: June 2021

Human induced pluripotent stem cells can differentiate into many cell types offering new resources for genetic disease modeling, drug development and cell‐based therapies. We have shown that iPSC derived endothelial cells (iPSC‐EC) are fully competent for diverse endothelial functions. However, iPSC‐EC are unique for their lack of an anatomical site of origin and lack of exposure to blood flow. Here we assessed if distinct EC subpopulations expressing arterial or venous EC markers exist within the differentiating iPSC embryoid bodies. We observed that CXCR4+/− EC exist within the embryoid body and that the CXCR4+ EC express greater levels of EphrinB2 and Hey2 compared to CXCR4‐ EC. Further, previous studies have documented that arterial or venous EC identity, while initially genetically specified, is plastic and can be modulated by biomechanical forces. We documented that application of arterial or venous specific shear stress waveforms to isolated iPSC‐EC differentially induced arterial or venous EC markers EphrinB2, Hey1, Hey2, Notch4, and VEGF. These results suggest iPSC can yield arterial/venous EC in the absence of flow; but the fate of iPSC‐EC in culture is sensitive to the de novo application of biomechanical forces. WJA is a recipient of a NIH Ruth L. Kirschstein National Research Service Award (1F31AG037249).
A Novel small molecule Inhibitor to C‐Reactive Protein attenuates CRP's Pro‐Inflammatory Effects In‐Vivo
Authors: Jialal Ishwarlal , Kumaresan Pappanaicken R , Lam Kit S , Devaraj Sridevi
Published: June 2021

Elevated C‐reactive protein (CRP) levels predict cardiovascular disease and augur a poor prognosis in patients with acute coronary syndromes. Much in vitro and in vivo data support a role for CRP in atherogenesis. There is an urgent need to develop inhibitors that specifically block the biological effects of CRP in vivo. Using the one‐bead‐one‐compound (OBOC) combinatorial library method, we recently used a novel fluorescent based screening method to screen OBOC combinatorial library for the discovery of peptides against human CRP and wished to examine effects in vitro and in vivo. Human CRP was labeled with FITC and Human serum albumin (HuSA) was labeled with PE and used for screening. The OBOC library LWH‐01 was synthesized on TentaGel resin beads using standard solid phase “split/mix” approach. By subtraction screening, 8 peptides that bind specifically to CRP and not to human serum albumin (HuSA) were identified. In HAEC incubated with CRP, inhibitors CRPi‐2, CRPi‐3 and CRPi‐6 significantly inhibited CRP‐induced superoxide, cytokine release and nuclear NFκb activity (p<0.05). Molecular docking studies demonstrate that CRPi‐2 interacts with the two Ca2+ ions in the single subunit of CRP. Treatment of CRP‐injected Wistar rats for 4 days with CRPi‐2 resulted in significant reduction in superoxide release, cytokines (IL‐1, TNF, IL‐8 and MCP‐1) release and NFκb activity compared to rats treated with CRP alone (p<0.05). There were no toxic effects as evidenced by routine clinical laboratory tests. In conclusion, we identify a novel inhibitor to CRP which attenuates its biological effects both in‐vitro and in‐vivo and in future studies will examine the utility of this inhibitor in longer term studies in animal models.
Glycocalyx Core Proteins Selectively Mediate Endothelial NOS activation and Cell Alignment in Response to Shear Stress
Authors: Ebong Eno Essien , Spray David C , Tarbell John M
Published: June 2021

In this work, we clarified mechanisms by which the endothelial cell (EC) glycocalyx (GCX) mediates flow‐induced nitric oxide (NO) release and cell remodeling. We tested two hypotheses: (1) The glypican‐1 (GPC1) GCX core protein mediates flow‐induced EC NO synthase (eNOS) activation, because GPC1 is located in the caveolae where eNOS resides; and (2) The syndecan‐1 (SDC1) GCX core protein is involved in flow‐induced EC remodeling, because it has a cytoskeleton‐bound tail. EC monolayers with intact GCX, RNA‐silenced GPC1, or RNA‐silenced SDC1 were exposed to physiological shear stress for 3 to 24 hours. Shear‐conditioned EC with fully intact GCX exhibited eNOS activation in short‐term flow conditions and characteristic elongation and alignment in the direction of flow after long‐term exposure. GPC1 inhibition, not SDC1 reduction, blocked shear‐induced eNOS activation. EC remodeling in response to flow was attenuated in the absence of SDC1, but preserved with GPC1 knockdown. These findings provide evidence that the GCX GPC1 and SDC1 core proteins selectively mediate important endothelial cell responses to shear stress. Research support: 5T32HL007675, HL094889.
HDAC7 mediated activation of STAT3 in human PTEN deficient glioma cells suppresses angiogenesis and tumor growth in vivo
Authors: Turtoi Andrei , Blomme Arnaud , Castronovo Vincent
Published: June 2021

Phosphatase and tensin homolog (PTEN) is a key tumor suppressor whose loss is commonly found in glioblastoma multiforme (GBM). In GBM, loss of PTEN leads to inactivation of signal transducer and activator of transcription 3 (STAT3). In contrast to the pro‐oncogenic function of STAT3 in other tumors, STAT3 has emerged as a key tumor suppressor in PTEN−/− GBM.

We report for the first time a histone deacetylase 7 (HDAC7) mediated mechanism of STAT3 activation in PTEN−/− GBM. SiRNA induced depletion of HDAC7 in human U87 glioma cells triggered (both in vitro and in vivo) phosphorylation of STAT3 on Y705. In accordance to our previous data, we show that this event is dependent of A‐kinase anchor protein 12 (AKAP12), which is rapidly induced upon HDAC7 silencing. In vivo, siRNA mediated HDAC7 repression abrogated tumor growth in U87‐glioma chick‐chorioallantoic membrane animal model. This effect was reversible when AKAP12 was co‐supressed. Intrigued by the macroscopical appearance of U87 tumors upon HDAC7 silencing, exhibiting small, pale nodules with prominent hemorrhage, we verified if defects in angiogenesis may explain the lack of tumor growth. Indeed, lectin‐based staining of the tumor vasculature revealed a significantly decreased vessel density. We demonstrate that several angiogenesis relevant genes (e.g. angiopoietin 1, angiogenin, interleukin 8) were significantly down‐regulated at transcriptional level.

The present study highlights a STAT3 dependent pathway for suppressing the growth PTEN−/− GBM with potential for clinical translation.

This work is sponsored by FNRS, Belgium.
STAT3 activation in cardiac hypertrophy induced by ryanodine receptor 2 mutation
Authors: HUANG TAIQIN , LEE JIN‐HYUP , ZOU MINXU , PASEK DANIEL A , WILLIS MONTE S , MEISSNER GERHARD
Published: June 2021

Ryanodine receptor 2 (RyR2) is a 2,200 kDa ion channel that is activated during an action potential to release Ca2+ required for cardiac muscle to contract. RyR2 mutant mice (RyR2‐ W3587A/L3591D/F3603A or Ryr2ADA) impaired in regulation by calmodulin show cardiac hypertrophy and survive about two weeks. We hypothesized that signal transducer and activator of transcription‐3 (STAT3) may play a role in cardiac hypertrophy of Ryr2ADA/ADA mice. We found that the protein expression levels of pSTAT3 and IL‐6, an upstream effector of STAT3, were increased in 10 day old Ryr2ADA/ADA mouse hearts but STAT3 expression was maintained. Corresponding with an increased nuclear translocation of pSTAT3 in Ryr2ADA/ADA mice, mRNA expression levels of ANP and c‐fos in left ventricular hearts were greatly increased in Ryr2ADA/ADA mice. The mutant mice also showed higher protein expression level of c‐fos and Chip assay indicated enrichment of STAT3 target genes ANP and c‐fos in the nuclei. The results suggest that activated STAT3 signaling pathway may play an important role in the development of cardiac hypertrophy in mice with dysfunctional ryanodine receptor. Supported by NIH.
Role of Hepatocyte Nuclear Factor 4 alpha in Promotion of Hepatocellular Carcinoma
Authors: Walesky Chad , Gunewardena Sumedha , Edwards Genea , Borude Prachi , Apte Udayan
Published: June 2021

Recent studies indicate that HNF4α inhibits hepatocyte proliferation but the mechanisms are unclear. We investigated the mechanisms of HNF4α‐mediated inhibition of hepatocyte proliferation using an inducible HNF4α knockdown mouse model. Deletion of HNF4α in adult mice resulted in increased hepatocyte proliferation. RNA seq‐mediated global gene expression analysis revealed that a significant number of the 500+ up‐regulated genes are associated with cell proliferation and cancer. A combined bioinformatics analysis of ChIP‐seq/RNA‐seq data indicated that a substantial number of up‐regulated genes are putative HNF4α targets. IPA analysis revealed the most significantly activated gene network following HNF4α deletion is regulated by c‐Myc. To determine the role of HNF4α in the pathogenesis of HCC, we utilized the diethylnitrosamine (DEN)‐induced HCC model. Deletion of HNF4α resulted in promotion of DEN‐induced hepatic tumors, which were highly proliferative, less differentiated, and exhibited a significant up‐regulation of pro‐mitogenic proteins (c‐ Myc and Cyclin D1). These data indicate that HNF4α inhibits hepatocyte proliferation and is a tumor suppressor gene in the liver.
Regulation of hepatic stellate cell activation through LRP1: a novel signaling role for t‐PA in liver
Authors: Kang Liang‐I , Bowen William C. , Orr Anne , Muratoglu Selen C. , Strickland Dudley K. , Michalopoulos George K. , Mars Wendy M.
Published: June 2021

Hepatic stellate cell (HSC) activation and trans‐differentiation into myofibroblast‐like (MFB‐like) cells is a key process in liver injury and fibrogenesis, a known prelude to cirrhosis. This study investigated the role of tissue‐type plasminogen activator (t‐PA) and its receptor, LRP1, in HSC activation. Primary rat HSCs or rat HSC‐T6 cells were treated with t‐PA from 1 min to 48 hrs. We find that at 24 hrs, t‐PA antagonizes activation of primary HSC and HSC‐T6 cells, as indicated by decreases in α‐SMA protein and collagen type I mRNA. Further, 48 hr treatment with t‐PA reduces cell viability. Non‐proteolytic t‐PA is also an antagonist, indicating a signaling mechanism. Increased p‐LRP1, followed by p‐AKT, is seen shortly after treatment (within 10 min), and antagonism of LRP1 or PI3K/AKT pathways, using specific inhibitors, is able to inhibit p‐AKT and prevent t‐PA‐mediated decreases in α‐SMA. After acute liver injury using carbon tetrachloride, mice lacking t‐ PA (globally) or LRP1 (conditionally in HSCs) retain higher density of an α‐SMA+, MFB‐like cell population compared to control mice by 4–7 days after cessation of injury. These data show that t‐PA is able to control HSC activation in vitro in an LRP1‐ dependent manner, and that interruption of LRP1 function in HSCs sustains MFB‐like cell populations during recovery after acute injury in vivo. Supported by NIH R01‐CA035373 (GKM, WMM) and F30DK091959 (LIK).
Biogenic amines secreted by cholangiocarcinoma modulate macrophage activation
Authors: Leyva‐Illades Dinorah , DeMorrow Sharon
Published: June 2021

Cholangiocarcinoma (CCA) arise from the neoplastic transformation of epithelial cells that line bile ducts. In addition to neoplastic cells, the tumor microenvironment consists of inflammatory cells and fibroblasts, which support tumor growth. Most tumor‐associated macrophages (TAMs) have an M2‐like anti‐tumor phenotype. How TAMs are involved in CCA progression remains unclear. CCA cells secrete increased amounts of serotonin and dopamine leading to increased proliferation; however, additional consequences of this secretion remain to be studied. The aim of this study was to determine the effects of serotonin and dopamine on macrophage activation. Macrophages were found in both benign and CCA tumors as evidenced by CD68 immunoreactivity, while IL‐10 (marker of M2 macrophages) was only found in CCA tissue. IFNγ increased cell surface MHCII expression measured by flow cytometry whereas pretreatment with CCA conditioned media (CM), serotonin, or dopamine dampened MHCII expression. CIITA mRNA expression (major regulator of MHCII expression) increased after IFNγ treatment which was dampened with CCA CM or serotonin. Treatment with CCA CM, serotonin or dopamine inhibited the nuclear translocation of Stat1 without altering the phosphorylation status. These data suggest that biogenic amines may play a role in the phenotypic switch from M1 to M2 of TAMs in the CCA tumor microenvironment.
Brain‐computer interfaces for replacing, restoring, or improving CNS function
Authors: Wolpaw Jonathan Rickel
Published: June 2021

Brain‐computer interfaces (BCIs) provide the CNS with new nonmuscular output pathways by measuring brain activity and converting it into artificial outputs that replace, restore, enhance, supplement, or improve natural CNS output and thereby change the ongoing interactions between the CNS and its external or internal environment. They use non‐invasive methods such as EEG and fMRI and invasive methods such as intracortical recording. Their most immediate uses are to restore basic communication and control to people severely disabled by ALS, strokes, or other disorders. They may also prove useful for guiding rehabilitation, and may supplement or improve function in people without disabilities.
Electrical and magnetic stimulation to improve brain function
Authors: Pascual‐Leone Alvaro
Published: June 2021

Brain stimulation methods use electrical or magnetic stimuli delivered non‐invasively or invasively to modify brain function. Deep brain stimulators are now widely used to improve motor function in people with Parkinson's disease, and their uses in a variety of other situations, including psychiatric disorders, are being explored. Non‐invasive magnetic stimulation is being used to assess corticospinal connectivity both in the laboratory and in the clinic. Repetitive magnetic stimulation is proving able to modify a variety of important brain functions. These include the acquisition of new motor skills, emotional valences, and memory.
Milk 3′ sialyllactose does not increase brain sialic acid concentration in mice
Authors: Autran Chloe , Szyszka Alexandra , Bode Lars
Published: June 2021

Sialic acid (Sia), a carboxylated 9‐carbon monosaccharide, is a crucial constituent of brain glycoproteins and glycolipids associated with brain development and enhanced cognitive function. Brain Sia concentrations rapidly increase after birth and are significantly higher in breast‐fed than in formula‐fed infants. Compared to formula, human breast milk contains a high amount of sialylated oligosaccharides; yet their direct role in brain Sia accrual is unknown. Our objective was to determine whether sialylated milk oligosaccharides contribute to brain Sia accumulation in mice between birth and weaning. To overcome problems with artificial feeding in newborn pups, we used a cross‐foster approach with pups reared on dams normal or genetically deficient in 3′sialyllactose (3′SL), one of the major sialylated milk oligosaccharides. Urine 3′SL and brain Sia were derivatized and measured by HPLC. While pups reared on dams with normal milk 3′SL had significantly higher urine 3′SL levels than pups fed on 3′SL deficient milk (460 vs. 40 uM at day 7, P<0.001), there was no significant difference in brain Sia one week (6.0±1.1 vs. 6.0±1.2 pmol/ug protein) and three weeks after birth (19.0±9.7 vs. 15.0±4.9 pmol/ug protein). The data indicate that 3′SL, one of the major sialylated milk oligosaccharides, does not contribute to postnatal brain Sia accumulation – at least in mice.

Grant Funding Source: NIH
TGR5, bile acids and the metabolic syndrome.
Authors: Schoonjans Kristina
Published: June 2021

Low‐grade chronic inflammation, obesity and insulin resistance are all risk factors intimately linked with the metabolic syndrome. Interestingly, many of the signaling pathways that control inflammatory responses also intersect with those that control nutrient metabolism. Earlier work from our laboratory has demonstrated that BAs, through TGR5 activation, can exert systemic metabolic effects by promoting energy expenditure and GLP‐1 secretion, thereby preventing obesity and insulin resistance during high fat diet feeding. Activation of TGR5 signaling also suppresses pro‐inflammatory cytokine production in macrophages via a mechanism that involves inhibition of NFkB nuclear translocation and attenuates the development of atherosclerosis in LDLR−/− mice. More recently, we investigated the properties of macrophage TGR5 in the context of diabesity. We demonstrate that diet‐induced obese Tgr5−/− mice develop severe insulin resistance and exhibit increased adipose tissue and liver inflammation as a result of increased macrophage migration. These results underscore the importance of an intact TGR5 signaling pathway in macrophages to prevent and combat chronic inflammatory diseases, such as atherosclerosis and diabesity.
Kinesins – How the ATPase Cycle Modulates Function
Authors: Gilbert Susan P.
Published: June 2021

Kinesins are necessary for a wide range of essential cellular functions, and while these molecular motors share common structural motifs, key amino acid residue changes confer unique mechanochemical properties to each kinesin, which in turn specify cellular function. We have defined the ATPase cycle of three processive kinesin motors using presteady‐state kinetic and thermodynamic methodologies. Our results for conventional Kinesin‐1, Kinesin‐5 Eg5, and Kinesin‐7 CENP‐E show that although each is processive and they share key characteristics, there are distinct mechanistic differences that alter the head‐head communication and microtubule interactions. The results for CENP‐E will be presented in comparison to Kinesin‐1 and Kinesin‐5 Eg5. Supported by NIH GM54141.
Mechanistic Analysis of HP1 heterochromatin assembly
Authors: Narlikar Geeta , Canzio Daniele , Liao Maofu , Naber Nariman , Pate Ed , Larson Adam , Wu Shenping , Cooke Roger , Schuck Peter , Cheng Yifan
Published: June 2021

The most conserved form of heterochromatin is characterized by methylation of lysine 9 on histone H3 (H3K9me3). Key to both the assembly and the spreading process is the heterochromatin protein 1 (HP1), which binds the H3K9me3 mark via its chromodomain (CD). This interaction forms a versatile platform for recruitment of different types of chromatin modifying proteins. However, the molecular basis of how the HP1‐H3K9me3 chromatin complex achieves these diverse interactions is yet to be understood. Our previous work on the S. pombe HP1 protein, Swi6, suggested that four molecules of Swi6 bind one nucleosome generating two vacant CDs, that can bridge adjacent nucleosomes. Our new data suggests that Swi6 switches between an auto‐inhibited state and bridging competent state upon binding methylated chromatin. We will present the biochemical data that lead to this model and an initial EM structure of Swi6 bound to nucleosomes that is consistent with this model. Our data also suggest testable hypothesis for how specific post‐translation modification on Swi6 can regulate its association with methylated chromatin and its interaction with the different heterochromatin proteins.
Redox Control of Chaperone Function
Authors: Jakob Ursula H , Reichmann Dana , Xu Ying , Ilbert Marianne , Cremers Claudia M , Fitzgerald Michael
Published: June 2021

Redox‐regulated proteins, which use reactive oxygen species to specifically regulate their protein function, play important roles in protecting organisms against oxidative cell damage. One such protein is the chaperone Hsp33, which uses a cysteine‐coordinating zinc site as functional redox switch. Under reducing non‐stress conditions, Hsp33 is chaperone‐inactive. Exposure to severe oxidative stress conditions causes rapid disulfide bond formation and zinc release in Hsp33 and triggers the oxidative unfolding of Hsp33's redox switch domain. This oxidative stress‐mediated unfolding makes Hsp33 a member of a new group of chaperones that need to lose their structure to gain function. Recent structural studies revealed how Hsp33 uses its intrinsically disordered regions to selectively bind unfolding intermediates under oxidative stress conditions and release them in a folding‐competent state upon return to non‐stress conditions. These studies form the basis for a new chaperone model in which ATP‐independent chaperones, like Hsp33, use stress‐mediated order‐to‐disorder transitions to regulate substrate binding and release. This mechanism allows chaperones to function under stress conditions, such as oxidative stress, where ATP is scarce and which result in the inactivation of many ATP‐dependent chaperones.
Dynamic complexes of intrinsically disordered proteins and their regulation by post‐translational modifications
Authors: Forman‐Kay Julie D
Published: June 2021

Intrinsically disordered proteins play a significant role in mediating protein interactions in biology. These binding events can involve disorder‐to‐order transitions of various degrees but many complexes retain significant flexibility within “fuzzy” or dynamic complexes. Examples of dynamic interactions regulated by phosphorylation or other post‐translational modifications of the disordered protein will be presented and the evidence for flexibility in the complexes highlighted. Included will be interactions that regulate cell cycle, ion flux, translation and embryogenesis, the latter involving large scale self‐association of the disordered protein into liquid‐like phase separated organelles. Importantly, the function of the binding/association, the post‐translational modification and the dynamics varies in each of these different systems. Links between the flexibility and function of the complex in these examples will be discussed.
Functional Interactions of Intrinsically Disordered Proteins in Signaling Networks
Authors: Wright Peter E
Published: June 2021

Intrinsically disordered proteins (IDPs) mediate critical regulatory functions in the cell, including regulation of transcription, translation, the cell cycle, and numerous signal transduction events. The lack of stable globular structure can confer numerous functional advantages, including, paradoxically, both binding promiscuity and high specificity in target interactions. IDPs frequently function in dynamic regulatory networks, where their propensity for posttranslational modifications, their rapid binding and dissociation kinetics, and their ability to interact with multiple target proteins makes them well adapted for precise transduction of cellular signals. The role of IDPs in dynamic cellular signaling will be illustrated by reference to pathways regulated by the general transcriptional coactivators CBP and p300, the tumor suppressor p53, and the adenovirus E1A oncoprotein. CBP and p300 are central nodes in eukaryotic transcriptional regulatory networks and transcription factors must compete for binding to the limiting concentrations of CBP/p300 present in the cell. Many intrinsically disordered proteins contain multipartite interaction motifs that perform an essential function in the integration of complex signaling networks. The role of multipartite binding motifs and post translational modifications in regulation of p53‐mediated signaling pathways will be discussed.
Leucine and calcitriol modulation of human airway inflammation in lung endothelial cells
Authors: Brown Patricia , Johnstone Megan , Zemel Michael B
Published: June 2021

Airway inflammation is substantially increased by obesity‐induced alterations of adipocyte‐derived cytokines. Previous studies from our lab demonstrated that leucine and calcitriol stimulate opposing effects on systemic inflammation and cytokine production in adipocytes and muscle cells. Accordingly, we hypothesized that dietary calcium (via suppression of calcitriol) and leucine will suppress adipose tissue derived TNFα and increase adiponectin release, resulting in suppression of hypertrophic growth and attenuation of chronic airway inflammation. Human and murine adipocytes were treated with calcitriol (10 nM) and leucine (0.5 mM) for 48 h and the conditioned medium (CM) were applied to human microvascular endothelial cells of the lung (HMVEC‐L). Calcitriol CM increased expression of the adhesion molecule ICAM‐1 (p<0.04), and leucine treatment reversed this effect (p<0.02). TNFα receptor 1 and NFκB expression exhibited comparable effects. Similarly, calcitriol suppressed nitric oxide release by HMVEC‐L, while leucine reversed this effect (p<0.02). In similar experiments in human airway smooth muscles cells (HASMCs), leucine reduced IL‐1B gene expression by 60% (p <0.002) and PDGF‐D by 70% (p<0.001). Thus, leucine suppresses inflammatory cytokines, increases vasodilation, and may reduce asthma‐associated hypertrophy in HMVEC‐L and HAMSCs, while calcitriol exerts the opposite effect.
HMGA2 inhibits apoptosis through interaction with ATR/CHK1 signaling complex in human cancer cells
Authors: Natarajan Suchitra , Hombach‐Klonisch Sabine , Droege Peter , Klonisch Thomas
Published: June 2021

Non‐histone chromatin‐binding High Mobility Group AT‐hook protein‐2 (HMGA2) is expressed in embryonic stem cells, absent in normal adult cells but re‐expressed in cancer cells. HMGA2 enhances chemoresistance and DNA base excision repair. Cancer cell models were treated with DNA‐damaging Methyl Methane Sulfonate (MMS) and let to recover. DNA damage was confirmed by immunofluorescence for γ‐H2AX and Comet assays. Upon MMS insult and during recovery, HMGA2 clones displayed significantly less γ‐H2AX foci, shorter comet tails and increased and sustained phosphorylation of CHK1 (pCHK1S296) and ATR (pATRS428). Sustained presence of pCHK1S296 and pATRS428 was dependent on the presence of HMGA2. Presence of pCHK1S296 coincided with a prolonged G2/M arrest in HMGA2 clones. CHK1 knockdown in MMS‐treated HMGA2+ cancer cells resulted in a significant increase in apoptosis that was enhanced further by knockdown of HMGA2 and HMGA2 was found to be a novel interacting partner with ATR and CHK1. In conclusion, upon DNA damage, HMGA2 (i) sustained activation of pCHK1 signaling, (ii) prolonged G2/M arrest, (iii) inhibited apoptosis and (iv) interacted with members of the ATR signaling cascade. Small inhibitors attenuating HMGA2 function may be a novel therapeutic strategy to target HMGA2+ cancers. This research was supported by NSERC and Surgery Research Fund.
Relationship between hepatic steatosis progression and cardiovascular performance under chronic nutritional overload
Authors: Nascimento Andre Ferreira , Luvizotto Renata AM , Martins Aline O , Oliveira Tamiris AS , Wang Xiang‐Dong , Cicogna Antonio C
Published: June 2021

To evaluate whether hepatic steatosis progression might be a risk factor for cardiovascular performance alteration under chronic nutritional overload. Male Wistar rats were divided to receive chow diet (C) or high‐fat diet plus sugar (300g/L of water) (H) for 6, 12 and 24 weeks. Adiposity index and hepatic and plasma triacylglycerol (TG) as well as free fatty acid (FFA) concentration were evaluated. Hepatic steatosis was analyzed by H&E staining. Cardiovascular performance was analyzed by a two‐dimensional echocardiography. Two‐Way ANOVA and post hoc Tukey test were used. The nutritional overload significantly increased adiposity index in all three experimental times in H group compared to C. The higher adipose tissue was associated with elevated plasma TG levels, while plasma FFA was influenced just with long‐term of obesity. The nutritional overload resulted in a time‐dependent hepatic steatosis progression in H group. Hepatic TG and FFA concentration was elevated in H group than C group in all moments. These metabolic changes in the livers did not result in any dysregulation of cardiac morphology and function. In conclusion, chronic nutritional overload induced and promoted hepatic steatosis progression. However, this metabolic scenario did not alter cardiovascular performance evaluated by in vivo two dimensional echocardiography. Supported by FAPESP: 2011/21664–9 and 2011/09945–2
Impact of caspase‐11 non‐canonical inflammasome on adipose tissue inflammation and obesity induced insulin resistance
Authors: Grant Ryan W. , Youm Yun‐Hee , Albarado Diana , Dixit Vishwa Deep
Published: June 2021

Sterile inflammation in the absence of overt infection contributes to insulin‐resistance and type 2 diabetes. IL‐1β mediates sustained tissue damage during the development of type 2 diabetes and is controlled by caspase‐1. Caspase‐1 is activated by multiple inflammasome protein complexes. We have shown that canonical Nlrp3 inflammasome activation participates in high‐fat diet induced adipose tissue inflammation and insulin‐resistance. Caspase‐11 has recently been identified as a non‐canonical inflammasome that leads to caspase‐1 activation in response to gram‐negative bacteria. Intestinal barrier function may be impaired during obesity and diabetes, making caspase‐11 a potential mediator of chronic inflammation during these diseases. Therefore we tested the hypothesis that caspase‐11 contributes to inflammasome activation, IL‐1β production and adipose tissue lymphocytosis during obesity. Our findings suggest that that high‐fat fed caspase‐11 −/− mice are not protected from lymphocytosis, adipose tissue inflammation and glucose and insulin intolerance. These data suggest that the caspase‐11 non‐canonical inflammasome is not the major innate immune sensor of obesity‐associated changes in endogenous gut microbial species that drive inflammation and insulin‐resistance. This research was supported in part by NIH DK090556, and RWG is supported by NIH DK064584.
Interprofessional Education in the Musculoskeletal Unit of Anatomical Sciences
Authors: Bee Mary T , Montante James , Orczykowski Mary , Ottenbreit Mark
Published: June 2021

The strength of our health professional students will only be as great as their ability to work with other members of the health care team. Interprofessional Education (IPE) refers to the collaborative learning that results when students from different fields learn with, from, and about each other. In 2010 the LCME set forth a directive that faculty should provide opportunities for interprofessional learning experiences. At our institution we grouped the first year medical students and the first year physical therapy doctoral students together for both anatomy lectures and laboratories during their musculoskeletal unit. In a qualitative study, students were asked about their thoughts on their involvement with their colleagues from the other field. We found that while students had both positive and negative experiences, overall students from both groups benefited from the experience (p<0.05). We advocate incorporating IPE in anatomy education elsewhere.
Integrating LGBT Issues into “Clinical Problem Solving (CPS)”, a First Year Medical School PBL Course
Authors: Rogers Ashley N , Rice Ami E , Packer C Subah
Published: June 2021

In CPS, students learn to work in small groups as they practice methodology necessary to case resolution. In addition to using basic science concepts, CPS students must consider ethical, legal, moral, social and communication issues. Recently, governing bodies (AAMC, LCME) promoted faculty awareness that medical students may be insensitive to LGBT issues. Accordingly, the current project objectives were: 1. assess in‐coming student knowledge of LGBT issues, 2. develop and implement a case in which the patient is a LGBT community member, 3. increase student self‐awareness of their understanding and attitudes of LGBT issues. Self‐awareness and at‐hand knowledge surveys were administered to students before they embarked on resolving the case. The average score on the LGBT basic knowledge questionnaire was 55.5%. Clearly there is a gap in knowledge of LGBT issues for in‐coming students. Project success is being evaluated through after student satisfaction surveys, faculty experience in implementing the new curriculum, and student learning outcomes.

(Supported by an IUPUI LGBT Faculty & Staff Council Grant)
Clinical Radiographic Anatomy Projects and their Impact around the World
Authors: Klinkhachorn Penprapa , Klinkhachorn Powsiri
Published: June 2021

Several computer‐assisted radiographic anatomy tutorials were developed in Adobe Flash, peer‐reviewed and published in MedEdPORTAL (MEP) of the Association of American Medical Colleges, and made available for gratis around the world. The publications were designed to serve as an introduction to normal x‐rays, angiography and cross‐sections of the Human body. Their rationale was to stimulate active self‐directed learning by integrating clinical application into a structured format that is readily accessible for local and distance learning. The tutorials complemented learning activities of the beginner health care professionals by providing them with opportunities for self‐assessment through quizzes. Some tutorials were accessed more than 100 times in less than 10 months. Users were from six continents, i.e., North and South America, Europe, Africa, Asia, and Australia, although the majority being from the United States. Usage report data from nine peer‐reviewed and published projects showed there was a total of 290 unique users from 64 countries downloading. 43% of total downloads were for teaching or training and 37% were for self‐directed learning. Others accessed them for curriculum development (15%), and a few used them for assessment and evaluation (5%). (Supported in part by NBAN account # 4910302000.12100083)
An Integrated, Flipped Classroom Model for Medical Education
Authors: Sawarynski Kara Elizabeth , Eastwood Jennifer L , Iyer Neena
Published: June 2021

In the medical education community, promoting active learning and more effectively integrating medical science disciplines are currently of primary concern. In this study, we present and evaluate an integrated, flipped classroom model for medical education. We “flip” the classroom by replacing two traditional lectures on overlapping content, but from two different disciplines, with short video lectures students watch online. We integrated content areas of cell biology, focusing on the cytoskeleton, and histology focusing on epithelia. In class, we integrate the disciplines through engaging students in clinically relevant problems and cases. In addition to describing a sharable model, we will discuss outcomes of our integrated, flipped session in an organ systems‐based preclinical medical curriculum. We found that student attitudes and perceptions of mastery were favorable for the flipped, integrated sessions as compared to traditional lecture sessions. However, students reported that the video lectures were less effective than traditional lectures. Qualitative data suggests that students did not perceive video lectures as important and came to class poorly prepared. Based on these results, we refine our model and offer implications of integrated flipped sessions in medical education, including session development, facilitation, and setting high expectations for student preparation.
Using Student‐Created Case Studies To Teach Respiratory Physiology
Authors: Hull Kerry
Published: June 2021

Case studies of pulmonary diseases are commonly used to illustrate various facets of respiratory physiology. Traditionally, students use clinical data to diagnose restrictive and obstructive lung diseases. This exercise takes a different approach, in which students construct and analyze their own case study and subsequently analyze the case study of a different student group. First, students completed a table comparing the clinical findings and etiology of restrictive and obstructive disorders. Second, student groups were assigned a category of disease (obstructive or restrictive). Using their table and a template case study for guidance, students developed a case study for a disease in their assigned category. A question set asked students to justify their clinical values and explain their clinical findings in the context of physiological models of elasticity and flow/gradients/resistance. Third, case studies were exchanged, and students answered the same set of questions for the received case study. Students’ answers to the questions revealed that most students achieved reasonable mastery of the concepts, and students found the exercise interesting and useful.
Undergraduate perceptions of human and anesthetised rabbit cardiovascular physiology practicals
Authors: Hodgson Yvonne M , Evans Roger , Denton Kate , Choate Julia
Published: June 2021

Since the 1960s until 2008 Monash University used an anaesthetised rabbit practical class to teach integrative cardiovascular physiology to science students. In the practical students performed surgery and investigated the effects of drugs and vagal stimulation on arterial pressure (AP) and heart rate (HR). Academics felt this practical was valuable for helping students to understand cardiovascular physiology, but in 2009 it was replaced with a human practical that uses a Finapres finger cuff to record AP and HR responses to mental, cold pressor, and orthostatic stress. This study evaluated students’ perceptions and learning following the rabbit (2008 cohort) or Finapres (2009 cohort) practical. More students taking the rabbit (than the Finapres) practical thought that it helped them to understand the control of AP. 88% of the students taking the rabbit practical agreed that it should be continued, indicating that there was no substitute for hands‐on experience. The students who disagreed said that the practical was only relevant to those who wanted to do research. The impact of the practicals on learning was determined by comparing 2008 and 2009 test results; these were not significantly different. Although more students thought the rabbit practical helped them to understand cardiovascular physiology, both the rabbit and Finapres practicals appear to have provided equivalent learning experiences.
Using simulated diving to teach undergraduate science students integrative physiology
Authors: Choate Julia , Evans Roger , Denton Kate , Hodgson Yvonne
Published: June 2021

The diving reflex can be simulated by breath‐holding together with facial immersion in water. Since it involves the combined responses of the cardiovascular, respiratory and nervous systems, it is ideal for teaching undergraduates integrative physiology. In 2009 we introduced a practical into our 3rd year physiology curriculum, based on the simulated diving laboratory described by Hiebert and Burch (2003). Our practical uses Finapres finger cuffs to continuously record heart rate (HR), arterial pressure (BP) and cardiac output (CO) during air‐breathing followed by apnea, breathing with a tube in cold water, or facial immersion in cold or warm water. Students worked in groups to analyse the data from 30 subjects and present this as a written report: facial immersion and tube breathing in water significantly reduced HR and increased BP; and all protocols reduced CO. Whilst the average mark for the group reports was 85%, most students received lower grades for an individual written response diving question on the exam (average = 64%). This trend was partially reversed in 2012 with the introduction of individual reports. In conclusion, a simulated diving practical can be used to teach students integrative physiology, but consideration should be taken into the format of the practical assessment as this may impact on student learning.