bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nuclear receptor ligands LG268 and rosiglitazone inhibit collagen destruction by chondrocytic cells stimulated with interleukin‐1 beta
Authors: Schmucker Adam , Burrage Peter , Brinckerhoff Constance 
Published: June 2021

Matrix metalloproteinase‐1 (MMP‐1) and MMP‐13 mediate cartilage destruction in arthritis. Our objective was to evaluate the inhibition of IL‐1β‐induced MMP‐1 and ‐13 expression in SW1353 chondrocytic cells by retinoid x receptor (RXR) ligand LG100268 (LG268), and peroxisome proliferator‐activated receptor gamma (PPARγ??ligand rosiglitazone (rosi).We pretreated SW1353 cells with LG268 and/or rosi, then added IL‐1ß (1 ng/ml). MMP‐1 and ‐13 hnRNA and mRNA was measured by realtime RT‐PCR, and cells were embedded in collagen to measure collagenolysis. Chromatin immunoprecipitation (ChIP) detected PPARγ?and acetylated histone H4 (AcH4) at the Activator Protein‐1/PPARγ response element (AP‐1/PPRE) in the MMP‐1 and ‐13 promoters. Modification of PPARγ and RXR by small ubiquitin‐like modifier (SUMO) was measured by IP and Western blot.LG268 and rosi reduced MMP‐1 and ‐13 mRNA, AcH4 at the AP‐1/PPRE, and collagen destruction, and combined rosi/LG268 treatment had an additive effect. Treatment with rosi or LG268 led to SUMOylation of PPARγ and RXR, respectively, and induced "cross SUMOylation" of the other partner in the PPARγ:RXR heterodimer. Unexpectedly, ChIP indicated increased PPARγ at the AP‐1/PPRE in IL‐1β‐treated vs. untreated cells, while rosi and LG268 had little effect.LG268 and rosi inhibit IL‐1ß‐induced MMP‐1 and ‐13, and reduce collagen destruction in vitro, likely by multiple mechanisms.Funding SupportACS: T32‐AR‐07576; PSB: T32‐AI‐07363; ACS, PSB, CEB: NIH ‐AR‐26599, 2.
Histone and factor covalent modifications in genome regulation
Authors: Berger Shelley L. 
Published: June 2021

Genomic structure and function is regulated in part through covalent post‐translational modifications (PTMs) of factors and histones, including acetylation (ac), methylation (me), phosphorylation (ph), ubiquitylation (ub), and sumoylation (su). There are an enormous number of factor and histone PTMs. To make sense of this bewildering complexity, we focus on patterns, temporal sequences, and cross‐talk between PTMs in various models, including in yeast S. cerevisiae and in mammalian cells.In yeast we focus on dynamic changes in histone PTMs during transcription and other processes. We are trying to unravel the molecular outcomes of these PTMs, as well as their role in complex physiological processes, such as during gametogenesis and during replicative cell aging. We use the genetic approaches available in yeast to determine whether altered function of chromatin may have a direct role in these epigenetic pathways.In mammals we study PTMs of DNA‐bound transcription factors, using the tumor suppressor and transcription factor p53 as a model. We currently focus on methylation and phosphorylation of specific residues in the N and C termini of p53. We are investigating cross‐talk between these PTMs on p53, and mechanistically‐interrelated PTMs on histones. Such PTM cascades may play a central role in signaling to chromatin.
Stabilization of Reaction Intermediates in the Catalytic Cycle of Nitric Oxide Synthases
Authors: Tejero Jesus , Biswas Ashis , Wang Zhi‐Qiang , Page Richard C. , Haque Mohammed Mahfuzul , Hemann Craig , Zweier Jay L. , Misra Saurav , Stuehr Dennis J. 
Published: June 2021

Nitric oxide synthases (NOS) catalyze the synthesis of nitric oxide from L‐Arginine. NOS enzymes have a tryptophan residue that forms a hydrogen bond with the heme‐thiolate and a stacking interaction with the heme. To assess the importance of this residue we replaced it by histidine in inducible NOS. The W188H mutation had relatively small effects on L‐Arg binding and on enzyme heme‐CO and heme‐NO absorbance spectra, but increased the heme midpoint potential by 88 mV relative to wild‐type iNOSoxy. The crystal structure of the mutant showed that the His188 imidazole still stacked with the heme and was in position to form a hydrogen bond with the heme thiolate. Analysis of a single turnover L‐Arg hydroxylation reaction revealed that a new heme species formed during the reaction. Formation of this species required the presence of tetrahydrobiopterin (H4B) and its buildup appears to be coupled with the formation of the bound H4B radical. The decay of the intermediate species correlates with L‐Arg hydroxylation and formation of ferric enzyme.This indicates that the W188H mutation stabilizes an intermediate heme‐oxy species whose reactivity becomes rate‐limiting for L‐Arg hydroxylation. The conserved Trp residue in NOS may facilitate NO synthesis by tuning heme‐thiolate electronegativity. Additional research to identify the intermediate will be discussed.
Biphasic regulation of cell cycle by nitric oxide donors in promyelocytic HL‐60 cell line
Authors: Kumar Sachin , Barthwal Manoj Kumar , Dikshit Madhu 
Published: June 2021

Nitric oxide (NO) regulates a wide array of cell functions, proliferation, cytostasis and apoptosis. Role of NO in cell proliferation is however is less explored, which has been suggested to be dependent on the NO concentration, cell type and intracellular redox status. Present study explores the effect of NO donors [DETA‐NONOate (DETA‐NO) and SNAP] on the promyelocytic HL‐60 cells. NO induced proliferation of HL‐60 cell at lower concentration (1‐100 µM), which was evaluated by Thymidine incorporation, BrdU labelling and cell cycle analysis regardless of any apoptosis, while higher concentration (250µM‐1mM) promoted apoptosis as evident by change in mitochondrial potential, Caspase activation, nick and PI labelling. To investigate further the mechanism involved, expression profile of various CDK/ cyclins including CDK2, CDK6, Cyclin A, Cyclin B, Cyclin D1, p15, p27 was monitored, Expression of Cyclin B, CDK2 was increased at 10‐50 µM by DETA‐NO, while most of these cell cycle regulators were reduced at 1 mM DETA‐NO. This proliferative effect seems to be redox sensitive as effect was abolished by pretreatment of cells with DTT (2mM). NO (10‐50µM) also augmented nitrosylation of various proteins suggesting nitrosylation of important targets. The results obtained thus suggest that NO in a concentration dependent manner modulated cell cycle in the HL‐60 cells.The work was supported by CSIR and DBT India.
The Differential Role of Nitric Oxide Synthases in Ultraviolet Light B‐induced Apoptosis
Authors: liu wei , Wu Shiyong 
Published: June 2021

Ultraviolet light (UV) activates nitric oxide synthase(s) (NOSs), which produces nitric oxide (NO). However the involvement of each NOS in UV‐induced signaling is not clear. The role of NO in UV‐induced apoptosis remains controversial. In this study, we analyzed expression and activation of NOSs in UVB‐irradiated keratinocytes HaCaT. We also determined the roles of NOSs in UV‐induced apoptosis. Our data showed that the expression of nNOS was increased and then decreased at 12 h and 24 h post‐UV respectively. While eNOS expression was not changed by UV, a decreased amount of coupled eNOS with an increased amount of uncoupled eNOS was observed within half‐hour of UV‐treatment. There was no increased level of iNOS was detected after UV‐irradiation. These results suggested that UV‐induced NO elevation is mainly regulated by cNOS.To determine the role of each cNOS and NO in UV‐induced apoptosis, we analyzed the extent of effect of a broad NOS inhibitor N‐nitro‐L‐arginine methyl ester (L‐NAME) on apoptotic death of HaCaT upon UV‐irradiation. Our data showed that NO was increased almost immediately and peaked at 18 h after UV‐irradiation. A pulse inhibition of NOS in the early phase (0‐0.5 h) partially inhibits UV‐induced apoptosis. However, a prolonged inhibition of NOS (0‐18 h) promotes apoptosis after UV‐treatment. In addition, the caspase 3 activity, but not amount, was changed in the treated cells and was correlated with the PARP cleavage and apoptosis of the HaCaT cells. Base on the results, we propose that in the early stage of UV‐irradiation, eNOS is uncoupled and produces O2‐ and promotes apoptosis. In the late stage of UV‐irradiation, the expression of nNOS is increased and the elevated [NO] produced by nNOS inhibits caspase‐3 activity and apoptosis of the irradiated cells.
Inhibition of nitric oxide production by feverfew supercritical extract as part of a migraine model in vitro
Authors: Aviram Anat , Tsoukias Nikolaos M. , Melnick Steven , Ramachandran Cheppail 
Published: June 2021

Migraine is a chronic neurovascular condition characterized by a unilateral headache which affects approximately 12% of the population in the United States. Although the exact mechanism by which migraine headaches are initiated remains unknown, nitric oxide (NO) is suggested to play a key role in the pathogenesis of migraine and other headache syndromes. The purpose of this study is to examine the NO inhibitory properties of supercritical extract of feverfew (FF) as an herbal drug against migraine. To achieve this, we used murine macrophage (Raw 264.7) and human brain microvascular endothelial cell line (HBMEC) as migraine models in vitro. Each cell line was treated with lipopolysaccharide (LPS) or nitroglycerin (NTG) followed by treatment with varying concentrations of FF‐CO2 extract (0‐200 µg/ml) for 24 h. Supernatants were analyzed by nitric oxide quantification assay. In Raw264.7, LPS‐induced NO production was gradually inhibited by feverfew extract in a dose‐dependent manner. The inhibition commenced at 3% for 0.5 µg/ml feverfew extract to a maximum inhibition of 89% at 100 µg/ml FF. Furthermore, 100 µg/ml FF inhibited over 50% of LPS‐induced NO production in Raw264.7 within a period of 2 h. FF (50 µg/ml) also significantly inhibited 58% NTG‐induced NO production in RAW 264.7. In HBMEC, 100 µg/ml FF inhibited 27% of NTG‐induced nitrite + nitrate levels. These results serve as a prelude for further in vivo studies on the pre‐clinical development of feverfew supercritical extract against migraine headaches.[AA is supported by NIH/NIGMS R25 GM061347]
Anti‐inflammatory Actions and Mechanisms of γ‐Tocotrienol in Lipopolysaccharide‐stimulated Macrophages
Authors: Wang Yun , Jiang Qing 
Published: June 2021

We have shown that gamma‐tocopherol (γ‐T), the major form of vitamin E in US diet, possesses anti‐inflammatory activity by inhibition of cyclooxygenase‐2 (COX‐2) catalyzed prostaglandin E2 (PGE2) synthesis in lipopolysaccharide (LPS)‐stimulated RAW264.7 macrophages. Here in the same cellular system we investigated potential anti‐inflammatory activity of gamma‐tocotrienol (γ‐TE), another vitamin E form with unsaturated hydrophobic side chain. γ‐TE at as low as 5 µM inhibited LPS‐activated PGE2 and dose‐dependently reduced nitrite accumulation, but had no effect on cell viability or LPS‐induced expression of COX‐2 or inducible nitric oxide synthase. γTE inhibited LPS‐stimulated interleukin‐6 (IL‐6), an pro‐inflammatory cytokine, in a dose‐dependent manner, but had no effect on interlukine 10, an anti‐inflammatory cytokine. Mechanistic studies indicated that in this cellular system, COX‐2 expression is regulated by p38 MAPK signaling pathway, while IL‐6 is regulated by NFkB. Consistently, γTE treatment did not show any effect on phosphorylation of p38, but rather resulted in an inhibition of phosphorylation of IkBa, a key event during NFkB activation. Studies are undertaken to further understand the molecular target/mechanism and anti‐inflammatory actions of γTE. (Supported by R01AT001821, P01AT002620 and P50AT000477)Grant Funding SourceBy R01AT001821, P01AT002620 and P50AT000477
Effect of homocysteine (Hcy) lowering vitamins on S‐adenosylmethionine (SAM) and S‐adenosylhomocysteine (SAH) in older people.
Authors: Green Tim , Skeaff C Murray , Venn Bernard , Innis Sheila 
Published: June 2021

BackgroundElevated plasma Hcy is a risk factor for vascular disease but lowering Hcy with B‐vitamins, including folate, has generally not reduced vascular events in clinical trials. Elevated plasma SAH concentration may be a more sensitive indicator of vascular disease than Hcy (AJCN 2007;86:1581). However, SAH was not correlated with folate concentrations in one study indicating that folate supplementation may not lower SAH (Eur J Clin Invest 2003;33:17). The effect of Hcy lowering vitamins on plasma SAH is not clear.AimTo determine in healthy older people with mildly elevated Hcy (Mean = 17.1 µmol/L) whether lowering Hcy with B vitamins effects plasma SAM and SAH concentrations.MethodsThis was part of a larger trial to determine the effect of B vitamins on cognition in which 276 healthy participants (= 65 y) were randomized to receive a supplement containing folate (1 mg), vitamin B12 (500 µg) and B6 (10 mg), or placebo, for two years. Of these participants, we selected the first 50 from each treatment group and determined SAM and SAH at baseline and two years by HPLC MS/MS.ResultsPlasma Hcy was 4.4 (95% CI 3.2, 5.6; P<0.001) µmol/L lower at 2 years in the Vitamins group compared with the Placebo group. At 2 years, there were no significant differences in plasma SAM [+4% (95% CI ‐2, 10); P=0.18], SAH [+2 (95% CI ‐10, 10); P=0.61], or the SAM:SAH ratio [+10% (95% CI 0, 20); P=0.10] between the Vitamins and Placebo groups.ConclusionSupplementation lowered plasma Hcy but had no effect on SAM or SAH concentration.
Hypoxia factors and cytokines mRNA expression in visceral and subcutaneous adipose tissues (VAT and SCAT) in obese insulin resistant dogs. Effects of weight loss and fenofibrate treatment.
Authors: Leray Veronique , Le Bloc'h Jerome , Serisier Samuel , Nguyen Patrick 
Published: June 2021

Expansion of VAT and SCAT has been described to be associated with adipocyte hypoxia. That could lead to inflammation and insulin resistance (IR), but the link with obesity remains unclear. Our aim was to assess the expression of hypoxia and inflammation markers in VAT and SCAT, in obese IR dogs, and the effect of BW loss or fenofibrate treatment, which both improve insulin sensitivity.VAT and SCAT biopsies were taken from dogs in 3 different times: (a) when dogs were obese (group 1), (b) after they had been given fenofibrate (10 mg/kg BW) for 15 d (group 2) and (c) after they had been given a hypoenergetic diet and had recovered their ideal BW (group 3). mRNA expression of HIF‐variants 1, 4, 7, 8, HIF‐1A, IL‐1B, TNF‐A, IL‐1A, ubiquitine ligase and very long chain fatty acid (VLCFA) ligase‐5 was quantified using real time RT‐PCR.Fenofibrate did not affect BW (‐3%). Hypoenergetic diet resulted in a 25% BW lost. In VAT, mRNA expression was lower in groups 2 and 3, except IL‐1A and VLCFA‐ligase‐5. In SCAT, mRNA expression of only HIF‐1variant1 and VLCFA‐ligase‐5 was lower in the group 3 compared to group 1.These results confirm different metabolic responses in SCAT and VAT. They show a dramatic decrease in hypoxia factors expression in VAT in dogs after weight loss as well as at the end of the 15‐d fenofibrate treatment. This was concomitant to a decrease in cytokine expression, that could explain the improvement in insulin sensitivity.
Supplementation with the probiotic Lactobacillus casei Shirota has no immunomodulatory effect in healthy men with a low baseline NK cell activity
Authors: Watzl Bernhard , Bub Achim , Franz Charles M.A.P. , Seifert Stephanie 
Published: June 2021

Probiotics have been shown to modulate the immune system. In healthy humans, however, contradictory results were observed. Thus, in a randomized double‐blind, placebo‐controlled trial the effect of the probiotic Lactobacillus casei Shirota (LcS; 1,95x1010 cfu/day) on immune functions of healthy men with low baseline NK cell activity (n=34/group) was investigated (study period 8 wk, i.e. a 2‐wk run‐in period, 4 wk supplementation and a‐2 wk follow‐up). Individuals of the control group (n=34) consumed the same drink manufactured without LcS. LcS had no effect on NK cell activity and immune cell phenotypes in peripheral blood mononuclear cells. Further, phagocytic activity and intensity of monocytes and neutrophils, oxidative burst, cytokine secretion pattern and saliva SIgA concentrations did not differ between groups. The incidence of potentially pathogenic microorganisms including S. aureus and hemolytic streptococci in the nasopharyngeal microflora was also not changed. In summary, under the present conditions supplementation with LcS caused no immunomodulation. However, other dosages of LcS might be effective as indicated by trials using higher LcS dosages. Dietary habits of study subjects may also be relevant for the outcome of the trial and may impede a demonstration of immunomodulatory activities of probiotics in open studies.The study was supported in part by a grant from Yakult Honsha CO., Ltd.
Classic activation of 3D4/31 porcine alveolar macrophages using phorbol 12‐myristate 13‐acetate and ionomycin
Authors: Myers Jay L , Tagliaferro Anthony R 
Published: June 2021

We hypothesize that dietary n‐6 fatty acids can convert alveolar macrophages to an alternative phenotype that promotes a Th2 immune response and respiratory allergy in humans. Our purpose was to establish an in vitro model using a transformed line of porcine alveolar macrophages (3D4/31). Cell populations of 3D4/31 cells were cultured in RPMI growth media (GM) supplemented with 10% fetal bovine serum (FBS) and incubated at physiological conditions (5% CO2 and 37 C). Three 24‐well plates were seeded at 100,000 cells/well and divided by serum conditions; 10% FBS or 10% porcine serum (PorS). After a 24‐hour incubation, wells were inoculated with phorbol 12‐myristate 13‐acetate (PMA; 0.01 mg/ml) and ionomycin (0.05 mg/ml). At various time points up to 12 hours, conditioned media was removed, centrifuged and stored at ‐80 C until ELISA analysis for TNF‐a and IL‐10. Total mean TNF‐a secretion was 22% higher when using PorS supplemented GM compared to FBS (n=18; p<0.05). Between 3 and 6 hours post‐activation, mean TNF‐a concentrations increased linearly and PorS supplemented GM was 29% greater than FBS (p<0.05) at 6 hours. The media was not found to contain measurable levels of IL‐10. 3D4/31 cells secrete TNF‐a and not IL‐10 when activated by PMA/ionomycin and are capable of providing a classically activated macrophage model to investigate potential influences of n‐6 fatty acids.UNH Experimental Station Project H495.
A beef meal elicits a decrease in post prandial vascular function whereas a bison meal does not
Authors: Bennett Danielle , Askew E.W. , McDaniel J. , Fjeldstad A.S. , Mihalopoulos Jason , Harris R. A. , Richardson R.S. 
Published: June 2021

The flow mediated dilation (FMD) test is a noninvasive measurement that provides an index of vascular function. A high fat meal has been recognized to negatively impact endothelial‐mediated vasodilation and thus attenuate FMD. Bison meat typically contains 1/3 of the total fat compared to beef and has less saturated fat.PurposeThis study sought to determine the impact of an acute meal consisting solely of beef or bison meat on post prandial vascular function.MethodsNine healthy males (30 ± 5 yrs) participated in two brachial artery FMD trials before (PRE) and 4 hours after (POST) ingestion of 12 ounces (cooked weight) of bison or beef. The meals were ingested in random order with several weeks of washout between FMD measurements. Brachial artery diameter, blood velocity, and shear rate (area under the curve) were determined by ultrasound Doppler following 5 minutes of supra‐systolic cuff occlusion of the forearm.ResultsThere was no effect of either the beef or bison meal upon FMD when expressed traditionally as % dilation. However, FMD when corrected for shear rate revealed a significant decrease in FMD from PRE to POST for the beef meal (4.00 ± 1.24 x 10−4 vs. 2.66 ± 1.60 x 10−4) (P<0.01), but not the bison meal (4.96 ± 3.13 x 10−4 vs. 3.50 ± 1.49 x 10−4).ConclusionWhen variations in shear rate, the major stimulus for FMD, are taken into account, vascular function is significantly compromised by a beef meal, but not by an equivalent bison meal. The negative vascular impact of the beef meal, but not the bison meal was likely due to lower fat content of the bison or the differing fatty acid composition of the two meats.
The relationship between meal frequency and BMI in school‐children
Authors: Goldsbury Savannah J , Leidy Heather J , Gibson Cheryl A , Sullivan Debra K 
Published: June 2021

PurposeTo identify the relationship between meal frequency and BMI in children. Methods: This was a cross‐sectional, observational study involving 1070 children in grades 3‐5 (age 7‐12 y) from 12 elementary schools within the Kansas City, KS Public School District. Each child completed one testing day of height and weight measures to determine BMI for age and sex percentiles (BMI%); total energy intake and number of eating occasions per day (EO) were identified using a multiple pass 24‐h diet recall administered by trained nutritionists. Correlational analyses were performed to determine relationships between BMI%, EO, and total energy intake. BMI% was also examined according to EO categorized as <3, 3‐4, >5 EO.ResultsBMI% was 74 ± 27% (range: 0‐100); EO was 4 ± 1 (range: 1‐8); and total energy intake was 1677 ± 786 kcal/d (range: 104‐7273). Lower BMI% was associated with higher total energy intake (r: ‐0.116; p<0.001) and greater EO (r: ‐0.091 p<0.005). Main effects of categorized EO were observed for BMI% (p<0.05). Children consuming <3 EO had higher BMI% (80± 24%) vs. those consuming 3‐4 EO (73± 27%; p<0.05) and >5 EO (72 ± 28%; p<0.01).ConclusionIncreased energy intake in combination with increased meal frequency positively impacts BMI% in school‐aged children. This data suggests that increasing the number of eating occasions may be a beneficial strategy to combat obesity. Support: NIH: R01 HL080967‐01A2Grant Funding SourceNIH R01 HL080967‐01A2
Dietary Dehydroepiandrosterone Raises Serum Cytokine Levels in Zucker Rats
Authors: Svec Frank , Porter Johnny R. 
Published: June 2021

The effect of dietary DHEA (dehydroepiandrosterone) on the levels of serum cytokine of male Zucker rats was studied. There were 8 groups of rats with 5 animals in each group; half of the 40 rats were obese while the others were lean. Half of each phenotype were made diabetic with streptozocin and half of each group were fed rat chow that was supplemented with 0.15% DHEA for 7 days before sacrifice. Body weights, corticosterone, DHEA, glucose and insulin levels were measured as well as TNF‐alpha, IL‐1 , IL‐1 alpha, IL‐1 beta, IL‐2, IL‐6, and IL‐10. The animals that were diabetic lost weight over the period of observation while the non‐diabetic controls gained weight. DHEA had no statistically significant effect on body weight. Diabetes did not affect cytokine levels. DHEA treatment, on the other hand, led to clear increases in the levels of IL‐1 alpha, IL‐2,IL‐6. Subgroup analysis showed that the effect of DHEA was seen in both lean and obese animals. These results point to the mechanism by which DHEA enhances the immune response.(Supported by Millenium Trust Excellence Fund Grant HEF (2000‐05)‐04 and American Hear Association Grant Southern Consortium 9808326V)