bluuebunny/crossref_metadata_2025 huggingface dataset:
Daily calcium intake and prevalence of metabolic syndrome (MetS) risk factors in Mexican college student applicants
Authors: Teran‐Garcia Margarita , Mosley Michelle , Aradillas‐Garcia Celia , Andrade Flavia Cristina Drumon ,   UPAMIGOS group
Published: June 2021

We investigated the presence of MetS risk factors and calcium intake in normal weight (NW), overweight (OW), and obese (OB) applicants to the Universidad Autónoma de San Luis Potosí (UASLP), Mexico. Data includes 7,087 applicants, 12.6% reported to be on a diet. Preliminary data on a subset of 789 (41.4% males) 16–21 yrs with complete data on BMI, waist circumference (WC), systolic and diastolic blood pressure (SBP, DBP), fasting glucose, and calcium intake is reported. Nutrient data were obtained from a Willett FFQ adapted for the Mexican population. According to their BMI, 66.7% of the applicants had NW (n=504), 22.4% (n=169) were OW and 11% OB (n= 83). WC in NW subjects was 75±0.3 (mean±se) compared to 101±0.9cm in OB (p<0.0001). As BMI increased, SBP values rise from 110±0.4 in NW to 119±0.9 mmHg in OB (p<0.0001). DBP also increased as BMI increased (NW 71±0.3 vs. 77±0.7mmHg in OB individuals, p<0.0001). Higher glucose levels were observed in OB individuals (88.1±0.4 in NW and 91.3±0.8mg/dl in OB, p=0.001). In contrast, as BMI increased, reported calcium intakes decreased. Calcium intakes were 819.1±16.6, 766.5±27.8 and 724.4±39.8 mg, in NW, OW and OB respectively (p=0.04). We found lower calcium intakes in OB and OW individuals. It is possible that dieters' decreases in calcium intake could also contribute to the risk of developing metabolic syndrome. Additional risk factors will be investigated.
Flax seed oil protection from bleomycin‐induced lung vascular damage: a rat model
Authors: Mehrer Aaron , Kamal Afrin , Herndon Betty L , Fibuch Eugene , Quinn Tim , Molteni Agostino , Lawrenz Joshua , Smith Bradford , Nitz Jonathan , Gasper David , Baybutt Richard
Published: June 2021

Bleomycin, a widely used antineoplastic agent has been associated with severe pulmonary toxicity through production of acute interstitial pneumonia, pulmonary vasculitis and, eventually pulmonary fibrosis. Treatment by omega‐3 fatty acid in flax seed oil may reduce bleomycin induced lung injury. To test this hypothesis 72 rats were equally divided between diets receiving 15% fat as flax seed oil or corn oil (control). These two groups were further divided to receive either 8 units/kg body weight bleomycin or vehicle, intratracheally. Lungs were harvested at 2, 7, or 21 days and tissue was fixed and stained (H&E) for histopathology. Two investigators evaluated the bleomycin induced lung responses particularly the bleomycin‐induced pulmonary vasculitis by photographing five small caliber pulmonary arteries. These arteries were measured for pulmonary lumen patency and the ratio of media diameter/adventitia diameter. At days 7 and 21, bleomycin produced a significant reduction in lumen patency (p=0.01) and of media/adventitial diameter (p=0.02 all days) which was not evident when the rats were treated with the flax seed oil diet. At day 7 the flax seed oil group also showed a delay in edema formation, inflammatory cell infiltrate and reduced pulmonary septal thickness. This model presents a dietary regime which may protect against bleomycin pulmonary toxicity.

Support: Wheaton College General Endowment fund.
Membrane lipids, where they are and how they behave: Sphingolipids on the move
Authors: van Meer Gerrit
Published: June 2021

Throughout the biological world, a 3 nm hydrophobic film typically serves as the margin between life and death for individual cells. Biochemical and biophysical findings have provided a detailed model of membrane composition and structure, which includes the dynamic organization of lipids both across the lipid bilayer (lipid asymmetry) and in the lateral dimension (lipid domains). How do cells apply anabolic and catabolic enzymes, translocases and transporters, plus the intrinsic physical phase behaviour of lipids and their interactions with membrane proteins, to create the unique compositions and multiple functionalities of their membranes? When acquiring internal membranes and vesicular transport, eukaryotic cells started to synthesize sphingolipids and sterols. The physical differences between these and the glycerophospholipids must have enabled the cells to segregate lipids in the membrane plane. Localizing this event to the Golgi then allowed them to create membranes of different lipid composition, notably a thin, flexible ER membrane, consisting of glycerolipids, and a sturdy plasma membrane containing at least 50% sphingolipids and sterols. Besides sorting membrane proteins, during evolution the simple sphingolipids became involved in the execution and control of signaling by specific interactions with (membrane) proteins, for which their local metabolism and transport appear essential.
Racial Disparities in Hypertensive Cardiovascular Disease and Chronic Kidney Disease
Authors: Lea Janice P.
Published: June 2021

Epidemiologic studies have shown that hypertension (HTN) and its cardiovascular (CV) complications, carry significantly higher morbidity and mortality in African‐Americans (AA) compared with Caucasians. These observations may be partly explained by a higher prevalence of cardiovascular disease (CVD) risk factors, such as HTN, diabetes, and tobacco use among AA.

Chronic Kidney Disease (CKD) is not only a major risk factor for End‐Stage Renal Disease, but is a predictor of CVD and death. CVD mortality rates are 10‐fold greater in individuals with CKD. Blacks are disproportionately affected by hypertensive CKD with a 7‐fold higher incidence. Additional risk factors for progressive CKD include level of blood pressure control, proteinuria, low income, and genetic influences.

Microalbuminuria and CKD are well‐established risk factors for CV mortality in both diabetic and non‐diabetics and is directly associated with left ventricular hypertrophy and coronary heart disease. The prevalence of microalbuminuria is higher among diabetics and hypertensives as well as among AA compared to Whites.

In summary, African‐Americans have a higher burden of HTN, diabetes, CVD and of CKD. However, the pathophysiologic processes underlying this racial predisposition have not been fully elucidated.
Indole‐3‐Acetic Acid/Horseradish Peroxidase Induces Apoptosis in TCCSUP Human Urinary Bladder Carcinoma Cells
Authors: Jeong Yun Mi , Kim Su Yeon , Li Hailan , Yun Hye‐Young , Baek Kwang Jin , Kwon Nyoun Soo , Kim Won Yong , Kim Dong‐Seok
Published: June 2021

In the present study, we determined the effects of IAA/HRP treatment on TCCSUP human urinary bladder carcinoma cells. IAA/HRP combination decreased cell viability of TCCSUP cells in a time‐ and dose‐dependent manner, whereas IAA or HRP alone showed no such effect. In addition, the decreased cell viability was restored by pretreatment with ascorbic acid. To clarify the mechanism of death of TCCSUP cells by IAA/HRP, we investigated the signal transduction pathways related to the apoptosis. IAA/HRP activates p38 mitogen‐activated protein (MAP) kinase and c‐Jun N‐terminal kinase (JNK). We further investigated the IAA/HRP‐mediated apoptotic pathways and showed that IAA/HRP induces caspase‐8 and caspase‐9 activation, which results in caspase‐3 activation and poly(ADP‐ribose) polymerase (PARP) cleavage. To further confirm whether IAA/HRP induces apoptotic cell death, we performed a DNA fragmentation assay after IAA/HRP treatment and found that IAA/HRP‐treated cells showed typical apoptotic DNA ladder formation. From these results, we suggest that IAA/HRP induces apoptosis of TCCSUP human urinary bladder carcinoma cells via both death receptor‐mediated and mitochondrial apoptotic pathways.
Adiponectin mediates leucine‐induced adipocyte‐muscle cross‐talk
Authors: Sun Xiaocun , Zemel Michael B.
Published: June 2021

We previously showed that leucine modulates energy metabolism in both adipocytes and skeletal muscle cells. We found leucine to stimulate adipocyte‐skeletal muscle cell cross‐talk, resulting in decreased adipocyte lipogenesis and increased fatty acid oxidation and mitochondrial biogenesis in muscle cells. Although these effects appear to be mediated, in part, via multiple adipokines, the effect of leucine on adiponectin production and signaling is unclear. We report here that leucine modulates adiponectin production in a dose‐dependent manner up to 1mM, which increased adipocyte adiponectin production by 78% (p=0.016). These effects are specific to leucine, as other branched chain amino acids exerted no effect. Leucine also stimulated adiponectin type II receptor expression in C2C12 myotubes by 29% (p=0.0071) but had no effect on the more highly expressed type I receptor. Since our previous data suggested that leucine stimulation of mitochondrial biogenesis was mediated by Sirt1, we evaluated leucine effects on Sirt1 activity; leucine exerted no direct effect on muscle Sirt1 activity, but leucine and adiponectin each stimulated ~50% increases in Sirt1 activity in adipocytes and in muscle cell/adipocyte co‐cultures (p<0.005). These data indicate that leucine regulation of adipocyte and muscle energy metabolism is mediated, in part, via adiponectin.

Support: TN Agricultural Experiment Station.
Endothelial mechanotransduction with loss of shear is a signal for angiogenesis
Authors: Chatterjee Shampa , Hong NanKang , Yu Kevin , Fisher Aron B
Published: June 2021

We have reported earlier that ischemia in the pulmonary vasculature results in reactive oxygen species (ROS) generation due to KATP channel closure that leads to NADPH oxidase activation. Here we found that pulmonary endothelial cells respond to ischemia in vitro, by increasing their angiogenic potential as compared to cells in static culture. We also investigated ischemia in the vasculature in vivo by femoral artery ligation. Angiogenesis (neovascularization) was assessed by visualization of fluorescence microbeads in the ischemic tissue following their injection into tail vein of mice. Neovascularization observed in wild type mice at 5 days after ligation was significantly decreased in mice that were null for KATP channel, gp91phox subunit of NADPH oxidase or Akt1. Pulmonary microvascular endothelial cells and lungs isolated from these knockout mice do not produce ROS with ischemia. The ischemic tissues from wild type were analyzed for vascular endothelial growth factor (VEGF). Wild type mice showed increased expression of VEGF with ischemia which was not observed in KATP channel, gp91phox and Akt null mice. We conclude that ROS generated with endothelial mechanotransduction causes angiogenesis via increased VEGF expression. ROS thus represents an attempt at neovascularization to restore the impeded blood flow.
Salvianolic acid B Inhibits Stromal Cell‐Derived Factor‐1/CXCR4 Axis and Promotes Apoptosis on Vascular Smooth Muscle Cells
Authors: Wu Chieh‐Hsi , Pan Chuing‐Hsu
Published: June 2021

We attempt to explore whether salvianolic acid B (Sal.B) can inhibit SDF‐1α‐induced biological effects on vascular smooth muscle cells (VSMCs). Cellular effects of Sal.B on cell proliferation and migration were investigated in A10 cells by MTT assay, wound‐healing assay and flow cytometry. The regulation of ERK‐MAPK pathway, apoptosis‐associated proteins, FAK, CXCR4 and SDF‐1α were determined. The apoptotic effect of Sal.B was also examined by DNA ladder assay and cell cycle analysis on cultured VSMCs. Furthermore, the luciferase‐based assay was used to measure the promoter activity of NF‐κB on cultured VSMCs stimulated by 10 ng.mL−1 SDF‐1α and/or 0.075 mg.mL−1 Sal.B. SDF‐1α stimulated cell proliferation and migration, which can be significantly inhibited by Sal.B. The up‐regulation of CXCR4, FAK, phosphor‐FAK, Raf‐1, MEK, ERK1/2 and phospho‐ERK1/2 induced by SDF‐1α was also markedly decreased by Sal.B. Additionally, Sal.B markedly increased Bcl‐2 but decreased caspase‐3 leading to apoptosis in a dose‐dependent manner. SDF‐1α‐mediated increase of NF‐κB promoter activity was suppressed by Sal.B treatment. The inhibitory and apoptotic effects of Sal.B on SDF‐1α‐triggered proliferation and migration of VSMCs were exerted through decreasing CXCR4 expression and its downstream pathways, and activating caspase‐dependent apoptosis pathway.
Effect of DIDS and pCMBS on the CO2 permeability of human aquaporin‐5 (AQP5)
Authors: QIN XUE , BORON WALTER F
Published: June 2021

Recent work from our laboratory showed that AQP1, AQP4, and AQP5 each exhibits a characteristic ratio for indices of CO2 vs. NH3 permeability. However, the mechanism of CO2 transport is not well understood. Here, we used microelectrodes to monitor the maximum rise in extracellular surface pH (ΔpHS) caused by CO2 influx into Xenopus oocytes, and monitored cell swelling under hypotonic conditions to compute osmotic water permeability (Pf). Subtracting values of H2O‐injected oocytes from those expressing FLAG‐tagged human (h) AQP5 yielded hAQP5‐dependent (*) ΔpHS or Pf. Treating FLAG‐hAQP5 oocytes with 100 μM DIDS × 60 min decreased ΔpHS* by 80±23%, similar to the observation of Musa‐Aziz et al on rat AQP5 (2007 JASN abstract). The DIDS inhibition for FLAG‐hAQP5 was not different from 61±12% for FLAG‐hAQP5‐C182S (eliminating potential DIDS and pCMBS target) or from 66±16% for FLAG‐hAQP5‐K34N (eliminating potential DIDS target). DIDS did not affect Pf* for any construct. Treating with 1 mM pCMBS × 30 min had no effect on ΔpHS* for any construct. pCMBS modestly decreased Pf* for WT and K34N, but not for C182S. In conclusion, DIDS markedly reduces the CO2 but not H2O permeability of AQP5, whereas pCMBS reduces the H2O but not CO2 permeability. Thus, our data are consistent with the hypothesis that the major route for CO2 through AQP5 is not the monomeric aquapore. One candidate is the central pore between the four monomers.
Anti‐obesity effects of Emblica officinalis (Amla) are associated with inhibition of nuclear transcription factor, peroxisome proliferator‐activated receptor gamma (PPARγ)
Authors: Sato Ryuei , Buesa Lance Martinez , Nerurkar Pratibha Vivek
Published: June 2021

Emblica officinalis (EO), or Indian gooseberry, has been traditionally used in Ayurvedic herbal preparations as an anti‐aging or rejuvenating medicine. All parts of EO plants including the leaves, bark or fruit have demonstrated significant efficacy to alleviate inflammation, cancer, renal disease, and diabetes‐induced oxidative stress in rodent models. The objective of our study was to investigate the anti‐obesity effects of EO in mice fed 58% kcal high‐fat‐diet (HFD) for 16 weeks. Male C57BL/6J mice were randomized into four groups: 1) control, 2) EO (10% w/w), 3) HFD and 4) HFD + EO. EO had no significant effect on daily food intake but significantly inhibited body weight gain as well as adipose tissue weights in mice fed HFD. Mechanistic studies indicated that EO normalized adipose mRNA expression of nuclear transcription factor, peroxisome proliferator‐associated receptor gamma (PPARγ). Bioactive‐guided fractionation of EO demonstrated that aqueous extract was more effective in inhibiting lipid accumulation in 3T3‐L1 mouse adipocytes treated during differentiation. Future studies are warranted to identify the physiologically effective doses of EO and mechanisms involved in inhibiting adipocyte differentiation. [Grants: NCCAM (R21AT003719), USDA‐CREES (2004‐34135‐15182)].
Characterization of the orphan human (C‐X‐C) chemokine receptor type 7 receptor (CXCL7) on T lymphocyte cells
Authors: Vu John Peter , Germano Patrizia , Lu Yuxin , Pisegna Joseph
Published: June 2021

Chemokines function as the main regulators of leukocyte trafficking under inflammatory conditions. Chemokine receptors have a 7 transmembrane structure and belong to the G protein‐coupled receptor subfamily. G‐Protein coupled receptors (GPCRs) mediate cellular responses to a diverse array of signaling molecules such as neurotransmitters, phosophilipds, and peptide hormones. Receptors coupled to G proteins form the largest known family of surface receptors, however despite the identification of hundreds human GPCRs, more than half are termed orphan. Recently, a CXCL7 (RDC1) has been cloned as an orphan GPCR receptor that shares homology with chemokine receptors. Initially, RDC1 was reported as a receptor vasoactive intestinal peptide, however this observation was dismissed when it was shown that RDC1 could not account for calcitonin gene‐related peptide (CGRP) and adrenomedullin (ADM) binding.

Here we describe the characterization of the RDC1 receptor expression on T lymphocyte cells. Jurkat cells were stably transfected to overexpress the RDC1 receptor. Gene expression profiles were studied with transfected RDC‐1 and untransfected Jurkat cells 2 and 24 hour conditions in response to either anti‐CD3, CGRP, and ADM with and with out the partial CGRP receptor antagonist CGRP8‐37. Intracellular calcium signaling responded to CGRP, ADM, and slight inhibitory response to CGRP(8–37).

Based upon calcium signaling studies, the cells showed a response to anti‐CD3, CGRP and ADM and showed a slight response to CGRP(8–37). These results will permit a more detailed determination as to the localiazation and physiological function of this novel receptor.
Immune responses of mouse mucosal system to glycated and hydrolysed OVA
Authors: Zlotkowska Dagmara , Kozlowska J. , Rudnicka B. , Kostyra H.
Published: June 2021

Advanced glycation endproducts (AGEs) are created during the spontaneous reaction that occurs in the body and during protein processing. AGEs cause chronic hyperglycemia, contribute to vascular and renal dysfunction, and are potential antigens. Our recent work showed the mucosal immune system responses to naive, hydrolysed and glycated ovalbumin (OVA‐H, ‐G) gavages to Balb/C mice. There were no differences between groups in anti‐OVA IgG, IgA serum and fecal titers. Cultured B lymphocytes did not show differences in proliferation during stimulation with OVA; OVA‐G/H. B cell ELISpot showed high expression of specific IgA in inductive tissues from OVA‐G and ‐H group. FACS analysis showed significantly expressed CD4+ in mesenteric LN and PP in OVA‐H. Significant levels of CD4+TGFβ were found in OVA‐G group in PP, MLN, iLP, and in OVA‐H group in SPL, PP and iLP. Sorted CD4+ populations were cultured with OVA, OVA‐H, OVA‐G. It was found significant level of TGF‐β and IL‐4 in culture supernatant. Adding OVA‐G to the culture significantly affected the levels of IL‐17 in culture supernatant. This expression suggests that AGEs could induce T cell population Th17, which is recognized as a mediator in autoimmune pathology. The presence of strong TGF‐β responses, together with significant levels of Il4, may indicate of expression Th3 cells, which provides help for IgA and has suppressive properties for some immune cells. All groups showed positive DTH test responses after 48h. The presented protein modifications modulated mucosal immune response for OVA. Using low dose antigen immunization and modification could be the convenient way to modulate immune responses to protect against food allergies and other diseases. This work was supported by MSHE in Poland, Grant N312 32/0159.
Sulfenic Acid Modification of Kv1.5: A Redox‐Sensitive Fate Switch for Channel Surface Expression
Authors: Svoboda Laurie Kathleen , Reddie Khalilah G. , Carroll Kate S. , Martens Jeffrey R.
Published: June 2021

Atrial fibrillation, a life‐threatening arrhythmia, is strongly associated with oxidative stress. The voltage‐dependent potassium (Kv) channel, Kv1.5 is a prominent cardiovascular K+ channel that is vital for atrial repolarization. Numerous studies suggest that Kv channels are redox‐sensitive; however, a molecular link between oxidative stress and altered Kv1.5 expression/activity has not been established. We have discovered that Kv1.5 is modified with sulfenic acid, a novel, redox‐sensitive posttranslational modification to this channel. In HL‐1 cells, stabilizing sulfenic acid during acute oxidative stress decreases Kv1.5 cell surface expression and channel current. Sulfenic acid modification inhibits recycling of internalized Kv1.5 back to the cell surface and promotes channel degradation after chronic oxidant exposure. Thus, sulfenic acid modification of Kv1.5 represents a fate switch, in which further oxidation diverts the channel from a recycling to a degradation pathway, providing a molecular link between oxidative stress and altered channel expression in atrial fibrillation. Support: NIHGrants HL0270973 and T32ES07062 and AHA Predoctoral Fellowship 0910001G.
Arginine supplementation and arginase inhibition reverse hyperoxia induced enhancement of contraction and impairment of relaxation of lung parenchyma of rat pups
Authors: Ali Nuzhat K.M. , Sopi Ramadan B , Jafri Anjum , Zaidi Syed I.A.
Published: June 2021

Exposure of immature lungs to hyperoxia for prolonged periods contributes to neonatal lung injury and airway hyperreactivity. We hypothesize that hyperoxia will increase arginase activity and the inhibition of arginase activity or supplementation of arginine may reverse this process by restoring NO/cGMP signaling. RSV infection may also increase contraction or impair relaxation of lung strips. Rat pups (P0) were exposed to room air or 50% O2 for 7 days in the presence and absence of daily in vivo L‐arginine supplementation or arginase inhibition by Nω‐hydroxy‐L‐arginine (norNOHA). At 7 days graded electrical field stimulation (EFS) was applied to strips to contract or to relax the preconstricted strips. EFS‐induced contraction increased (60.8 ± 6.4% vs. 98.8 ± 8.6%, p<0.05) and relaxation impaired (35 ± 2.71% vs. 9.33 ± 4.13%, p<0.05) in hyperoxic vs. room air controls. This was associated with a significant increase in arginase activity (p<0.05) and expression of arginase I in alveolar epithelium of hyperoxic as compared to room air lungs. Supplementation with L‐arginine or inhibition of arginase activity by norNOHA restored contraction and relaxation of lung parenchyma. Additionally, at 7 days room air or hyperoxic pups were infected with RSV (106 MOI) and after five days lung strips were subjected to EFS for contraction/relaxation study. RSV infection also increased contraction and impaired relaxation of lung strips (P<0.05). Arginine supplementation and/or arginase inhibition may provide a useful therapeutic tool for the increased airway reactivity that occurs in hyperoxia exposed neonates. (Supported by NIH grant HL‐056470)
The IP3 receptor‐binding protein IRBIT reduces phosphatidylinositol 4,5‐bisphosphate (PIP2) stimulation of Na/bicarbonate cotransporter NBCe1 variants expressed in Xenopus laevis oocytes
Authors: Thornell Ian M. , Wu Jianping , Bevensee Mark O.
Published: June 2021

We have recently shown that PIP2 stimulates NBCe1 activity, and injecting PIP2 directly into an oocyte expressing NBCe1‐B or NBCe1‐C stimulates the NBC‐mediated, HCO3−‐induced outward current (INBC) by ~150%. Furthermore, PIP2 stimulation of the C variant requires the N terminal 87 residues found in the B and C variants, but not the A variant— a finding similar to the reported stimulatory effect of IRBIT on the B but not A variant. To explore the hypothesis that the PIP2 and IRBIT regulatory pathways overlap, we used the 2‐electrode voltage clamp technique to monitor the effect of injecting ~10 μM PIP2 (final) on INBC in oocytes (Vh = −60 mV) injected with a rat NBCe1 variant ± IRBIT cRNA(s). INBC was normalized to plasma membrane expression as determined by single‐oocyte chemiluminescence. For A variant‐expressing oocytes, coexpressing IRBIT augmented the small PIP2‐induced % increase in INBC from 8% ± 1 (n=2) to 66 ± 18% (n=8). Coexpressing IRBIT increased B variant INBC as previously reported, and increased C variant INBC by 448 ± 104% (n=8). For B variant‐expressing oocytes, coexpressing IRBIT reduced the PIP2‐induced % increase in INBC from 162 ± 23% (n=7) to 42 ± 7% (n=8). Similar results were obtained for the C variant, with a reduction in the PIP2‐induced % increase in INBC from 185 ± 30% (n=3) to 12% ± 3% (n=5). For oocytes expressing a C variant missing its 87 N terminal residues, coexpressing IRBIT did not affect INBC appreciably, and the PIP2‐induced % increase in INBC was less than 45% in the absence or presence of IRBIT. According to these data, IRBIT and PIP2 may compete with one another in stimulating NBCe1‐B and NBCe1‐C. NIH NS046653, AHA‐SE 0755255B
Nuclear import of RNA polymerase II requires the conserved GPN‐loop GTPase XAB1/GPN1
Authors: Lacombe Andree‐Anne , Forget Diane , Cloutier Philippe , Al‐Khoury Racha , Bouchard Annie , Lavallee‐Adam Mathieu , Jeronimo Celia , Archambault Jacques , Blanchette Mathieu , Coulombe Benoit
Published: June 2021

Over the past 3 decades, many efforts have been made to identify and characterize the factors that regulate the activity of RNA polymerase II (RNAPII), the enzyme that synthesizes all the mRNA and many small nuclear RNA in eukaryotes. Quite surprisingly, very little is known about the cell machinery that regulates the fate of RNAPII before or after transcription. In this study, we report that XAB1/GPN1, a member of a unique class of GTPases containing a conserved GPN‐loop, is involved in the biogenesis of RNAPII by regulating its nuclear import. XAB1/GPN1 is physically associated with RNAPII in the soluble cell fraction and is essential for cell growth. Accumulation of RNAPII in the cytoplasm of the cell was induced upon (i) depletion of XAB1/GPN1 by siRNA silencing, (ii) overexpression of a XAB1‐GFP dominant negative fusion protein, (iii) mutation of the GTP‐binding or GPN motifs of the XAB1/GPN1 homologue in yeast, NPA3, and (iv) treatment of cells with leptomycin B, an inhibitor of XPO1/CRM1‐dependent nuclear export. Yeast strains with mutations in the NPA3 gene showed hypersensitivity to benomyl, a specific inhibitor of microtubule assembly, suggesting a role for microtubules in RNAPII biogenesis. Together, these results indicate that XAB1/GPN1 shuttles between the cytoplasm and the nucleus to mediate nuclear import of RNAPII.
Early breastfeeding outcomes in gestational diabetic primiparas delivering term infants
Authors: Nommsen‐Rivers Laurie Ann , Chantry Caroline J , Dewey Kathryn G
Published: June 2021

By definition, gestational diabetes resolves after childbirth, but associations with establishing breastfeeding (BF) have not been documented. We recently reported the prevalence of early lactation difficulties among a cohort of 431 first‐time mothers delivering healthy term infants and initiating BF. Our objective here is to compare the prevalence of delayed onset of lactogenesis (delayed OL, defined as maternal perception of onset after 72 h) and other early BF outcomes between cohort participants with gestational diabetes (GD, n=27) and those without gestational, type 1 or type 2 diabetes (NoD, n=397). GD women were more likely to be obese (P=.007), but were similar in prenatal BF intentions and delivered infants of similar birth weight. In the first 24 h, GD infants (vs. NoD) were less likely to “breastfeed well” at least twice (69% vs. 88%, P=.007) and more likely to be given > 60 mL formula (15% vs. 6%, P=.08). The prevalence of delayed OL (GD vs. NoD) was 63% vs. 43% overall (P=.04) and 64% (7 of 11) vs. 36% (99 of 262) in the non‐obese subset, P=.08. By 72 h, 54% of GD infants (vs. 26% of NoD) received > 60 mL formula (P=.003). GD infants continued to be significantly more likely to receive formula at 3–7 (78% vs. 45%, P=.001) and 8–14 (59% vs. 31%, P=.007) days of age, despite similar maternal BF intentions. GD mothers are at risk for early lactation difficulties and should routinely be provided with professional BF support.
Effect of dietary supplementation with Laminaria japonica and Laminaria saccharina on loperamide‐induced constipation in rats fed high fat diet
Authors: Chang Kyung Ja , Xu Zhao , You JeongSoon , Huan Du , Lee Chong M
Published: June 2021

The purpose of this study was to investigate the effect of dietary supplementation with Laminaria japonica and Laminaria saccharina on loperamide‐induced constipation in the rats fed high fat diet for 9 weeks. Male Sprague Dawley rats were divided into 3 groups randomly: high fat diet (HF) group, high fat diet supplemented with L. japonica (HFJ) group, and high fat diet supplemented with L. saccharina (HFS) group. Constipation was induced by hypodermic injection of loperamide (10 mg/kg) for the final 3 days. The food efficiency ratio (FER) in the HF group was significantly higher compared to the HFS group, and the FER of the HFJ group was in the middle of the three groups. The serum total cholesterol level in the HFJ group was significantly lower compared to HFS group. Although there was no significant difference, the gastrointestinal tract ratio in the HFJ group was the least compared to other groups. The fresh fecal weight and water content in fecal were the least in the HF group and the most in the HFS group. This study suggested that L. japonica and L. saccharina can improve constipation in rats fed high fat diet. Therefore, these effects may provide the foundational data for development of functional foods using these seaweeds.
Probiotic Lactobacilli Decrease Invasion of Metastatic Human Colon Cancer Cells In Vitro
Authors: Escamilla Juanita , Lane Michelle A , Maitin Vatsala
Published: June 2021

Colon cancer metastasis involves loss of intercellular junctions and cell invasion through the colonic epithelial basement membrane, a process mediated by matrixmetalloproteinases (MMP). Probiotic bacteria have been shown to improve colonic epithelial barrier function and decrease MMP activity suggesting anti‐metastatic potential. The objective of this study was to explore anti‐metastatic activity of probiotics Lactobacillus casei (L. casei) and Lactobacillus rhamnosus (L. rhamnosus) in terms of decrease in cell invasion. This was assessed by an in vitro assay, measuring the invasion of metastatic human colon cancer cell line HCT‐116 through Matrigel‐coated membranes in Boyden chambers. HCT‐116 cells were plated on top of the membrane with probiotic CFS from either L. casei or L. rhamnosus at 25% (v/v) in DMEM. Bacterial growth medium (MRS) at 25% (v/v) in DMEM was used as the control. Cell invasion was measured after 24 h of treatment; by fixing, staining and counting the cells present on the bottom side of the membrane. Treatment of HCT‐116 cells with CFS from L. casei and L. rhamnosus resulted in a significant decrease in cell invasion by 72% +/− 4.25 and 50% +/− 17.65 respectively, of control. These data indicate that probiotic CFS contain anti‐metastatic bioactive compounds that may be contributing to the decrease in cell invasion in vitro. Funding source: Texas State University Research Enhancement Program.

Grant Funding Source: Texas State University Research Enhancement Program
A systematic review of the separate and combined effects of energy restriction and exercise on fat‐free mass in middle‐aged and older adults: Implications for sarcopenic obesity
Authors: Weinheimer Eileen , Sands Laura P , Campbell Wayne W
Published: June 2021

Purpose

This systematic review assessed the effects of energy restriction (ER) and exercise (EX) on fat‐free mass (FFM) in overweight and obese middle‐aged and older adults.

Methods

Pubmed was searched using “weight loss or energy restriction” AND “skeletal muscle or body composition” as keywords, with limitations “human” and “middle‐aged and aged.” 52 studies met inclusion criteria that included men and/or postmenopausal women aged ≥ 50 y, BMI > 25 kg/m2, and interventions ≥ 8 wk. Body weight (BW) loss was induced via ER, ER+EX, or EX. ER was achieved by counseling without (n=35) or with (n=7) some food provided, or all food provided (n=3). EX included aerobic (n=31), resistance (n=3), or both (n=5). Results are reported as % of the ER, ER+EX, or EX groups that had a specified change in BW and FFM, since insufficient data were provided to perform a meta‐analysis.

Results

94% of the ER groups and 89% of the ER+EX groups lost ≥ 5 kg BW. 75% of the ER groups, but only 30% of the ER+EX groups, lost ≥ 1.5 kg FFM. 81% and 39% of the ER and ER+EX groups, respectively, lost ≥ 15% of BW as FFM. The EX groups had modest BW (94% lost < 5 kg) and FFM (100% lost < 1.5 kg) losses.

Conclusion

Exercise is an effective tool to help middle‐aged and older overweight and obese adults preserve FFM after moderate energy restriction‐induced weight loss, and may be effective in combating sarcopenic obesity.

Support: T32AG025671; US Whey Protein Research Consortium

Grant Funding Source: T32AG025671; US Whey Protein Research Consortium
MBL‐associated serine protease 1 (MASP‐1) is necessary for thrombin substrate cleavage in vitro
Authors: La Bonte Laura R , Pavlov Vasile , Takahashi Minoru , Fujita Teizo , Takahashi Kazue , Stahl Gregory L.
Published: June 2021

Bleeding disorders and thrombotic complications constitute a major cause of death and disability worldwide. Previous research established a connection between the complement and coagulation systems; however no studies have specifically investigated the molecular mechanisms underlying this interaction. Thus, the purpose of this study was to elucidate the role of complement, specifically the lectin pathway, in thrombin‐like activity in vitro. MBL‐complexes were captured on mannan‐coated plates using serum collected from wild‐type (WT) and a variety of complement deficient mice. The captured MBL‐complexes were incubated with a chromogenic thrombin substrate, S2238, for 1.5hrs at 37°C, and cleavage was measured using a fluorometer. MBL‐complexes captured from WT, C2/fB−/−, MBL‐A−/− or MBL‐C−/− sera showed no significant difference in S2238 cleavage between groups. In contrast, complexes captured from MBL null and MASP‐1/3−/− mouse sera demonstrated significantly decreased S2238 cleavage compared to WT (P<0.01). Recombinant human (rh)MBL alone also failed to cleave S2238, yet cleavage could be restored when rMASP‐1 was added back to either MASP1/3−/− sera or rhMBL. Taken together, these findings indicate that the MBL‐complex with MASP‐1 has thrombin‐like activity, and may suggest a key role for lectin complexes in thrombus formation and coagulopathy in vivo. Supported by HL56086, HL92469 and HL99130.
MR Angiogenesis Imaging with Robo4‐ versus αVβ3‐ Targeted Nanoparticles in the B16/F10 Mouse Melanoma Model
Authors: Boles Kent , Schmieder Anne , Caruthers Shelton , Hu Grace , Scott Michael , Zhang Huiying , Reynolds Benton , Wickline Samuel , Lanza Gregory
Published: June 2021

The objectives of the present study were: 1) to compare noninvasive MR molecular imaging utilizing Robo4 and ανβ3–integrin as biosignatures of angiogenesis, 2) to determine the relative spatial distribution of Robo4 and ανβ3 within tumor neovessels, and 3) to assess the prevalence of angiogenesis in a mouse model implanted with a rapidly growing, syngeneic tumor. B16‐F10 melanoma bearing mice were imaged with MR (3.0T) 11 days post implantation after intravenous administration of Robo4‐, ανβ3–, irrelevant‐, or non‐targeted paramagnetic nanoparticles. Neovascular signal enhancement was predominantly associated with the tumor periphery where it was greater for ανβ3–integrin than Robo4 (p<0.05). The mean MR contrast enhancement in the tumor cores did not differ from zero in the ανβ3–, irrelevant‐, and non‐targeted groups and was similarly low, but greater than zero (p<0.006) in the Robo4 animals. Microscopic examination of tumors co‐exposed to the Robo4 and ανβ3–targeted nanoparticles corroborated the MR angiogenesis mapping results and further revealed that Robo4 expression generally colocalized with ανβ3– integrin. These results suggest that ανβ3–integrin and Robo4 are useful biomarkers for noninvasive MR molecular imaging in syngeneic mouse tumors.
Mild dehydration degrades mood and symptoms, not cognitive performance in females: a placebo‐controlled study.
Authors: Armstrong Lawrence E , Ganio Matthew , Lee Elaine , McDermott Brendon , Klau Jennifer , Yamamoto Linda , Marzano Stefania , Lopez Rebecca , Casa Douglas , Jimenez Liliana , Le Bellego Laurent , Chevillotte Emmanuel , Lieberman Harris R
Published: June 2021

Little definitive information is available on the behavioral effects of dehydration. This study assessed effects of mild dehydration on cognitive performance and mood of healthy females, without hyperthermia. Healthy, active women (N=25; mean ± SD age, 23.0 ± 0.6 y; using oral contraceptives) participated in 3 placebo‐controlled, randomized, single‐blinded, repeated measure trials (9.8 h each) in 3 hydration states: exercise dehydration (D; three 40‐min treadmill walks at 5.6 km·h−1, 5% grade, 28°C); D plus diuretic ingestion (D+F; furosemide, 40 mg); and control (CON; exercise, weight maintained by water intake). A comprehensive 6‐task cognitive test battery (CTB), Profile of Mood States questionnaire (POMS) and visual analog scales (VAS) were administered. Paired t‐tests compared CON (0.12 ± 0.06%) to all D and D+F trials that resulted in ≥1% (1.39 ± 0.30%) body mass loss. Differences (P<.05, CON versus D or D+F) existed at rest and during exercise for POMS (total mood disturbance, tension, vigor, fatigue, confusion) and VAS (task difficulty, concentration, headache). No differences in the CTB were observed. In conclusion, ratings of task difficulty, concentration and headache, as well as mood states were degraded by mild dehydration of 1.39% but cognitive performance was not. Funded by Danone Research, France.
Role of CD8+ T lymphocytes in the genesis of angiotensin II‐induced hypertension
Authors: Thabet Salim Riad , Chen Wei , Harrison David
Published: June 2021

We have shown previously that T lymphocytes play a major role in the genesis of both angiotensin II‐induced and DOCA‐salt hypertension. T cells include CD4+ helper cells and CD8+ cells, but the role of these subsets in hypertension is unclear. Mice lacking CD8+ lymphocytes (CD8−/−) exhibited a markedly blunted hypertensive response to angiotensin II (SBP: 132 ± 8 mmHg), while CD4−/− mice had a normal hypertensive response to this octapeptide (SBP: 178 ± 6 mmHg). Consistent with this, adoptive transfer of CD8+ from hypertensive mice to RAG1−/−caused a significant rise in blood pressure in the recipients, while transfer of CD4+ cells did not (SBPs: 188 ± 4 mmHg vs. 144 ± 6 mmHg respectively). In C57Bl/6 mice, angiotensin II stimulates marked infiltration of leukocytes and T cells into the perivascular fat, and this was markedly reduced in CD8−/− mice. We also found that hypertension increases IFNγ and TNFα production by CD8+ cells. These studies identify a previously undefined role for CD8+ cells in the genesis of hypertension and its attendant inflammation. Future studies are needed to elucidate the mechanisms of CD8+ cell involvement in this disease.
An Irreversible Modification of Histone H3 ‐ Identification and Characterization of Histone H3‐specific Protease from Chicken Liver
Authors: Chaturvedi Madan Mohan , Purohit Jogeswar S , Tomar Raghuvir Singh , Panigrahi Anil K
Published: June 2021

Regulated removal of N‐terminal tails of histones would constitute an irreversible type of modification. A novel histone H3 specific modifying enzyme from chicken liver nuclei was purified that specifically cleaved histone H3 in vitro and generated a faster migrating histone H3 band. The enzyme named H3ase was sequenced with the help of MALDI‐MS & PSD and was found to align with a known NAD+‐dependent dehydrogenase (NDH). The peptide substrates against the N‐terminus histone H3 could compete with H3ase activity, building the possibility that probably, H3ase modified histone H3 in the N‐terminus. Site of proteolysis was mapped using bacterially expressed recombinant histone H3. The cleaved products corresponded to polypeptides lacking 2, 4 and 8 amino acid residues from the N‐terminus, respectively. The mechanism of proteolysis is still unknown. Efforts are being taken to evaluate the status of H3 proteolysis in chromatin level and to find out its physiological importance.

This research work was supported by research grants from Department of Science and Technology, Government of India, New Delhi (Grant no. SR/SO/BB‐38/2002), and University of Delhi, India.
The host is a harsh mistress: role of fatty acid synthesis in trypanosome survival (1001.6)
Authors: Paul Kimberly , McKnight Ciara , Ray Sunayan
Published: June 2021

Trypanosoma brucei, a protozoan parasite transmitted by the tsetse fly, invades the bloodstream and CNS of humans, causing African sleeping sickness. In addition to antigenic variation of its surface glycoprotein coat, T. brucei employs a second immune evasion tactic: upregulation of endocytosis to clear lytic cell surface immune complexes, a strategy likely involving membrane turnover and fatty acid synthesis (FAS). Acetyl‐CoA carboxylase (ACC) catalyzes the first committed step of FAS and is a regulatory control point. Previous work showed that ACC RNA interference (RNAi) in T. brucei bloodstream forms (BFs) reduced virulence in mice, but had no effect on growth in culture. We hypothesized that ACC is required in BFs for immune evasion via endocytosis upregulation. We examined endocytosis in BF ACC RNAi cells and observed a 90% reduction in fluid phase and receptor‐mediated endocytosis upon ACC RNAi. ACC RNAi also caused a 30% delay in the clearance of surface‐bound antibodies and 40% increase in the susceptibility to complement‐mediated lysis. Because endocytosis upregulation may increase demand for FAS, we examined if ACC is regulated in response to changes in lipid supply. In BFs, we found no change in ACC expression, activity, or phosphorylation upon growth in low or high lipid media. Also, ACC RNAi had similar effects on endocytosis, antibody clearance, and complement‐mediated lysis under low and high lipid conditions. In contrast, insect form cells exhibited a 2X increase in ACC protein and enzymatic activity in low lipid media. Phosphorylation of insect form ACC increased 3X in high lipid media and decreased by 80% in low lipid media. We propose a model whereby T. brucei ACC is up‐regulated in the mammalian host to support increased endocytosis and immune evasion, while in the insect host, ACC is regulated in response to the environmental lipid supply.

Grant Funding Source: Supported by NIH R15 AI081207
Sumo‐modification of pxr alters protein cofactor interactions (1062.11)
Authors: Woody Sarah , Staudinger Jeff
Published: June 2021

Pregnane X Receptor (PXR, NR1I2) is a ligand‐activated nuclear receptor superfamily member expressed at high levels within the entero‐hepatic system in mammals. The primary function of PXR is to regulate the metabolism and transport of xenobiotics and endogenous compounds by controlling the expression of genes encoding major drug metabolizing enzymes and drug transporter proteins. To mediate its function PXR interacts with a plethora of classical co‐regulatory proteins including, but not limited to, Nuclear Receptor Co‐Repressors (NCoR1/NCoR2), Steroid Receptor Co‐activator proteins (SRC‐1/SRC‐2/SRC‐3) and p300/CBP co‐integrator proteins. SUMOylation is a reversible post‐translational modification that plays a central role in regulating multiple cellular activities such as protein‐protein interactions. While direct PXR‐target gene activation programs are currently well characterized, little is known about SUMO‐modification of PXR. Our working hypothesis is that SUMO‐modified PXR alters its protein‐protein interaction profile. Thus, we have created a GAL4‐PXR fusion system that allows us to directly examine SUMO‐PXR interaction with the aforementioned PXR‐binding proteins. Future efforts are focused on developing novel methods for identification of SUMO‐PXR‐binding proteins using non‐biased methods.

Grant Funding Source: Supported by NIH DK090558
GAPDH prevents oxidant‐induced apoptosis in smooth muscle cells via upregulation of APE1/Ref‐1 endonuclease (1093.1)
Authors: Sukhanov Sergiy , Yoshida Tadashi , Delafontaine Patrick
Published: June 2021

We have shown that oxidized low density lipoprotein (OxLDL) co‐localized with apoptotic smooth muscle cells (SMC) in atherosclerotic plaque and that OxLDL downregulated the major glycolytic enzyme glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) in cultured SMC via H2O2‐dependent mechanism. We hypothesized that GAPDH downregulation mediates SMC apoptosis.

OxLDL (80 ug/ml) or H2O2 (220 uM, 16h) decreased GAPDH protein (immunoblotting, 78±5% and 55±5% decrease, respectively) and induced TUNEL‐positive DNA fragmentation and apoptosis (Annexin V assay). GAPDH downregulation with siRNA potentiated OxLDL‐ or H2O2‐induced DNA fragmentation (1.9±0.2 and 7.0±0.9‐fold increase, respectively) suggesting that maintenance of sufficient GAPDH levels is critical for DNA integrity and cell survival. GAPDH transient overexpression with pCMV‐GAPDH construct decreased H2O2‐induced cytotoxicity (LDH release assay, 68±5% decrease) and DNA fragmentation (74±4% decrease). SMC constitutively overexpressing GAPDH had increased glycolysis, ATP levels and these cells were resistant to H2O2‐induced cell death (>90% reduction) showing that GAPDH protects SMC against oxidant‐induced apoptosis. We have found that GAPDH was co‐immunoprecipitated and had nuclear co‐localization with APE1/Ref‐1 endonuclease, major DNA repair enzyme. APE1 endonuclease activity was increased in H2O2‐treated GAPDH overexpressing SMC vs.control SMC suggesting that GAPDH preserved APE1 activity under oxidative stress.

In summary, GAPDH downregulation mediates oxidant‐induced SMC apoptosis and forced expression of GAPDH protects SMC from oxidant‐induced cell death potentially via stimulation of APE1‐dependent DNA repair. Since SMC apoptosis induces vulnerable plaque phenotype and accelerates atherosclerosis, our data suggest that preservation of GAPDH and APE1 activity in plaque SMC could represent novel therapy to prevent plaque destabilization and atherogenesis.

Grant Funding Source: Supported by American Heart Association
Heat stress and reduced feed intake alter the intestinal proteomic profile (246.1)
Authors: Pearce Sarah , Huff‐Lonergan Elisabeth , Lonergan Steven , Baumgard Lance , Gabler Nicholas
Published: June 2021

Heat stress (HS) and reduced feed intake have been shown to negatively affect intestinal integrity and barrier function. Our objective was to compare ileum protein profiles of pigs subjected to HS, thermal neutral (TN), or reduced feed intake conditions. Twenty‐four pigs (n=8/treatment) were assigned to one of these treatments for 12 h: 1) TN (21°C; 70% humidity with ad libitum intake, 2) HS (37°C; 40% humidity with ad libitum intake), or 3) TN conditions but pair fed (PFTN) to mirror nutrient intake of the HS pigs. Pigs were then euthanized, whole ileum was collected, and protein extracted. Proteins were solubilized and 2D‐Differential In Gel Electrophoresis (DIGE; 24 gels in duplicate), 11cm strips pH 3‐10, in the first dimension and 12.5% acrylamide gels in the second dimension, was performed. Relative abundance of 281 and 138 proteins were significantly different (P < 0.05) due to HS, compared to TN and PFTN pigs respectively. However, only 20 proteins were significantly different due to reduced feed intake alone (P < 0.05). Differentially expressed proteins were identified by electrospray mass spectrometry (ESI/MS). Compared to TN and PFTN pigs, heat shock proteins 27, 70, 90‐α and β were increased during HS. However, metabolic enzymes isocitrate dehydrogenase and glyceraldehyde‐3‐phosphate dehydrogenase were decreased in HS pigs (75 and 10% respectively; P < 0.05) compared to TN and PFTN pigs. Similarly, stress response enzymes peroxiredoxin‐1 and peptidyl‐prolyl cis‐trans isomerase A were decreased (40 and 15% respectively; P < 0.05) in PFTN and TN pigs compared to HS. Interestingly, prolyl‐4‐hydroxylase‐β was reduced 10% in HS and PFTN pigs compared to TN controls. Together, these data show that HS directly alters intestinal protein profiles during a severe heat‐load, largely independent of reduced feed intake.

Grant Funding Source: Supported by USDA‐AFRI grant# 2011‐67003‐30007