Molecular Impacts of Dietary Exposure to Nanoplastics Combined or Not with Arsenic in the Caribbean Mangrove Oysters (Isognomon alatus)

Nanoplastics (NPs) are anthropogenic contaminants that raise concern, as they cross biological barriers. Metals’ adsorption on NPs’ surface also carries ecotoxicological risks to aquatic organisms. This study focuses on the impacts of three distinct NPs on the Caribbean oyster Isognomon alatus through dietary exposure. As such, marine microalgae Tisochrysis lutea were exposed to environmentally weathered mixed NPs from Guadeloupe (NPG), crushed pristine polystyrene nanoparticles (PSC), and carboxylated polystyrene nanoparticles of latex (PSL). Oysters were fed with NP-T. lutea at 10 and 100 µg L−1, concentrations considered environmentally relevant, combined or not with 1 mg L−1 pentoxide arsenic (As) in water. We investigated key gene expression in I. alatus’ gills and visceral mass. NP treatments revealed significant induction of cat and sod1 in gills and gapdh and sod1 in visceral mass. As treatment significantly induced sod1 expression in gills, but once combined with any of the NPs at both concentrations, basal mRNA levels were observed. Similarly, PSL treatment at 100 µg L−1 that significantly induced cat expression in gills or sod1 in visceral mass showed repressed mRNA levels when combined with As (reduction of 2222% and 34%, respectively, compared to the control). This study suggested a protective effect of the interaction between NPs and As, possibly by decreasing both contaminants’ surface reactivity.

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The usefulness of competitive PCR: airway gene expression of IL-5, IL-4, IL-4δ2, IL-2, and IFNγ in asthma

Thorax ◽

10.1136/thx.56.7.541 ◽

2001 ◽

Vol 56 (7) ◽

pp. 541-548

Author(s):

E M Glare ◽

M Divjak ◽

M J Bailey ◽

E H Walters

Keyword(s):

Gene Expression ◽

Inhaled Corticosteroids ◽

In Situ Hybridisation ◽

Housekeeping Gene ◽

Cross Sectional Study ◽

Mrna Levels ◽

Competitive Pcr ◽

Cross Sectional ◽

Steroid Use ◽

Biopsy Specimens

BACKGROUNDAsthma has been described as an eosinophilic bronchitis driven by interleukin(IL)-4 and IL-5. The quantification of cytokine mRNA levels in airway samples has been confounded by housekeeping gene expression which differs between and within asthmatics and controls.METHODSThe usefulness of competitive reverse transcriptase-polymerase chain reaction (RT-PCR) that is independent of housekeeping gene expression for quantitating the mRNA for interferon (IFN)γ, IL-2, IL-5, IL-4 and its receptor antagonist encoding splicing variant IL-4δ2 was determined in a cross sectional study of 45 normal control subjects and 111 with asthma.RESULTSAtopic controls and atopic asthmatic subjects expressed more IL-5 than non-atopic controls (p<0.02) in bronchoalveolar lavage (BAL) cells, but not in biopsy specimens. IL-5 mRNA expression in BAL cells from asthmatic subjects using inhaled corticosteroids (ICS) was significantly lower than those not receiving ICS (p=0.04). IL-2 mRNA levels differed with steroid use in biopsy specimens but not in BAL cells. IFNγ, IL-4, and IL-4δ2 mRNA levels did not differ between any groups and were not affected by steroid use. IL-4 and IL-4δ2 mRNA levels were positively correlated (p<0.0001), suggesting coordinated transcription.CONCLUSIONSWhile the signal differentiation of competitive PCR in asthma may rival that of in situ hybridisation and immunohistochemistry, the method is expensive and wasteful of material.

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Methylobacterium oryzae Influences Isoepoxydon Dehydrogenase Gene Expression and Patulin Production by Penicillium expansum

Water ◽

10.3390/w13101427 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1427

Author(s):

Tiago Barros Afonso ◽

Lúcia Chaves Simões ◽

Nelson Lima

Keyword(s):

Gene Expression ◽

Distribution Systems ◽

Water Distribution ◽

Penicillium Expansum ◽

Transcriptional Level ◽

Positive Trend ◽

Mrna Levels ◽

Expression Levels ◽

Production Values ◽

Methylobacterium Oryzae

Biofilms can be considered the main source of microorganisms in drinking water distribution systems (DWDS). The ecology of a biofilm is dependent on a variety of factors, including the presence of microbial metabolites excreted by its inhabitants. This study reports the effect of the Gram-negative bacteria Methylobacterium oryzae on the idh gene expression levels and patulin production of Penicillium expansum mature biofilms. For this purpose, a RT-qPCR method to quantify idh mRNA levels was applied. In addition, the idh expression levels were compared with the patulin production. The results obtained revealed that the effect of the bacterium on pre-established P. expansum biofilms is dependent on the time of interaction. More mature P. expansum biofilms appear to be more resistant to the inhibitory effect that M. oryzae causes towards idh gene expression and patulin production. A positive trend was observed between the idh expression and patulin production values. The results indicate that M. oryzae affects patulin production by acting at the transcriptional level of the idh gene.

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Hepatocellular expression of glucose-6-phosphatase is unaltered during hepatic regeneration

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1998.275.4.g717 ◽

1998 ◽

Vol 275 (4) ◽

pp. G717-G722 ◽

Cited By ~ 3

Author(s):

Wisam F. Zakko ◽

Carl L. Berg ◽

John L. Gollan ◽

Richard M. Green

Keyword(s):

Gene Expression ◽

Enzyme Activity ◽

Protein Expression ◽

Partial Hepatectomy ◽

Initial Phase ◽

Physiological Function ◽

Liver Homogenate ◽

Hepatic Regeneration ◽

Mrna Levels ◽

Microsomal Enzyme

Gluconeogenesis and glycogenolysis are essential hepatic functions required for glucose homeostasis. During the initial phase of hepatic regeneration, the immediate-early genes (IEG) are rapidly expressed, and the IEG RL-1 encodes for glucose-6-phosphatase (G-6- Pase). G-6- Pase is a microsomal enzyme essential for gluconeogenesis and glycogenolysis. This study employs a partial-hepatectomy model to examine the expression and activity of G-6- Pase. After partial hepatectomy, rat hepatic G-6- Pase gene expression is transcriptionally regulated, and mRNA levels are increased ≈30-fold. However, in contrast to this rapid gene induction, microsomal enzyme activity is unchanged after partial hepatectomy. Western blotting demonstrates that microsomal G-6- Pase protein expression is also unchanged after partial hepatectomy, and similar results are also noted in whole liver homogenate. Thus, despite marked induction in gene expression of the IEG G-6- Pase after partial hepatectomy, protein expression and enzyme activity remain unchanged. These data indicate that, although this hepatocyte IEG is transcriptionally regulated, the physiologically important level of regulation is posttranscriptional. This highlights the importance of correlating gene expression of IEG with protein expression and physiological function.

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Inhibition of polyamine synthesis induces p53 gene expression but not apoptosis

AJP Cell Physiology ◽

10.1152/ajpcell.1999.276.4.c946 ◽

1999 ◽

Vol 276 (4) ◽

pp. C946-C954 ◽

Cited By ~ 46

Author(s):

Li Li ◽

Ji Li ◽

Jaladanki N. Rao ◽

Minglin Li ◽

Barbara L. Bass ◽

...

Keyword(s):

Gene Expression ◽

Growth Inhibition ◽

P53 Protein ◽

Specific Inhibitor ◽

P53 Gene ◽

Mrna Levels ◽

Intestinal Epithelial ◽

Polyamine Biosynthesis ◽

Fetal Bovine ◽

P53 Mrna

The nuclear phosphoprotein p53 acts as a transcription factor and is involved in growth inhibition and apoptosis. The present study was designed to examine the effect of decreasing cellular polyamines on p53 gene expression and apoptosis in small intestinal epithelial (IEC-6) cells. Cells were grown in DMEM containing 5% dialyzed fetal bovine serum in the presence or absence of α-difluoromethylornithine (DFMO), a specific inhibitor of polyamine biosynthesis, for 4, 6, and 12 days. The cellular polyamines putrescine, spermidine, and spermine in DFMO-treated cells decreased dramatically at 4 days and remained depleted thereafter. Polyamine depletion by DFMO was accompanied by a significant increase in expression of the p53 gene. The p53 mRNA levels increased 4 days after exposure to DFMO, and the maximum increases occurred at 6 and 12 days after exposure. Increased levels of p53 mRNA in DFMO-treated cells were paralleled by increases in p53 protein. Polyamines given together with DFMO completely prevented increased expression of the p53 gene. Increased expression of the p53 gene in DFMO-treated cells was associated with a significant increase in G1 phase growth arrest. In contrast, no features of programmmed cell death were identified after polyamine depletion: no internucleosomal DNA fragmentation was observed, and no morphological features of apoptosis were evident in cells exposed to DFMO for 4, 6, and 12 days. These results indicate that 1) decreasing cellular polyamines increases expression of the p53 gene and 2) activation of p53 gene expression after polyamine depletion does not induce apoptosis in intestinal crypt cells. These findings suggest that increased expression of the p53 gene may play an important role in growth inhibition caused by polyamine depletion.

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Metallothionein gene expression and secretion in white adipose tissue

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2000.279.6.r2329 ◽

2000 ◽

Vol 279 (6) ◽

pp. R2329-R2335 ◽

Cited By ~ 24

Author(s):

Paul Trayhurn ◽

Jacqueline S. Duncan ◽

Anne M. Wood ◽

John H. Beattie

Keyword(s):

Gene Expression ◽

Molecular Weight ◽

Adipose Tissue ◽

White Adipose Tissue ◽

Stromal Vascular Fraction ◽

Low Molecular Weight ◽

Secretory Product ◽

Mrna Levels ◽

Gene Encoding ◽

Adrenoceptor Agonist

White adipose tissue (WAT) has been examined to determine whether the gene encoding metallothionein (MT), a low-molecular-weight stress response protein, is expressed in the tissue and whether MT may be a secretory product of adipocytes. The MT-1 gene was expressed in epididymal WAT, with MT-1 mRNA levels being similar in lean and obese ( ob/ ob) mice. MT-1 mRNA was found in each of the main adipose tissue sites (epididymal, perirenal, omental, subcutaneous), and there was no major difference between depots. Separation of adipocytes from the stromal-vascular fraction of WAT indicated that the MT gene (MT-1 and MT-2) was expressed in adipocytes themselves. Treatment of mice with zinc had no effect on MT-1 mRNA levels in WAT, despite strong induction of MT-1 expression in the liver. MT-1 gene expression in WAT was also unaltered by fasting or norepinephrine. However, administration of a β3-adrenoceptor agonist, BRL-35153A, led to a significant increase in MT-1 mRNA. On differentiation of fibroblastic preadipocytes to adipocytes in primary culture, MT was detected in the medium, suggesting that the protein may be secreted from WAT. It is concluded that WAT may be a significant site of MT production; within adipocytes, MT could play an antioxidant role in protecting fatty acids from damage.

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Role of arachidonic acid metabolism in transcriptional induction of tumor necrosis factor gene expression by phorbol ester.

Molecular and Cellular Biology ◽

10.1128/mcb.9.1.252 ◽

1989 ◽

Vol 9 (1) ◽

pp. 252-258 ◽

Cited By ~ 75

Author(s):

J Horiguchi ◽

D Spriggs ◽

K Imamura ◽

R Stone ◽

R Luebbers ◽

...

Keyword(s):

Gene Expression ◽

Arachidonic Acid ◽

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Leukotriene B4 ◽

Mrna Levels ◽

Arachidonic Acid Release ◽

Acid Release ◽

Tnf Gene ◽

Necrosis Factor

The treatment of human HL-60 promyelocytic leukemia cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) is associated with induction of tumor necrosis factor (TNF) transcript. The study reported here has examined TPA-induced signaling mechanisms responsible for the regulation of TNF gene expression in these cells. Run-on assays demonstrated that TPA increases TNF mRNA levels by transcriptional activation of this gene. The induction of TNF transcripts by TPA was inhibited by the isoquinolinesulfonamide derivative H7 but not by HA1004, suggesting that this effect of TPA is mediated by activation of protein kinase C. TPA treatment also resulted in increased arachidonic acid release. Moreover, inhibitors of phospholipase A2 blocked both the increase in arachidonic acid release and the induction of TNF transcripts. These findings suggest that TPA induces TNF gene expression through the formation of arachidonic acid metabolites. Although indomethacin had no detectable effect on this induction of TNF transcripts, ketoconazole, an inhibitor of 5-lipoxygenase, blocked TPA-induced increases in TNF mRNA levels. Moreover, TNF mRNA levels were increased by the 5-lipoxygenase metabolite leukotriene B4. In contrast, the cyclooxygenase metabolite prostaglandin E2 inhibited the induction of TNF transcripts by TPA. Taken together, these results suggest that TPA induces TNF gene expression through the arachidonic acid cascade and that the level of TNF transcripts is regulated by metabolites of the pathway, leukotriene B4 and prostaglandin E2.

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Nitric oxide increases IL-8 gene transcription and mRNA stability to enhance IL-8 gene expression in lung epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00165.2004 ◽

2004 ◽

Vol 287 (4) ◽

pp. L764-L773 ◽

Cited By ~ 34

Author(s):

Loretta Sparkman ◽

Vijayakumar Boggaram

Keyword(s):

Gene Expression ◽

Nitric Oxide ◽

Protein Kinase ◽

Epithelial Cells ◽

Gene Transcription ◽

Mrna Stability ◽

Inflammatory Responses ◽

Lung Epithelial Cells ◽

Mrna Levels ◽

Lung Epithelial

Interleukin (IL)-8, a C-X-C chemokine, is a potent chemoattractant and an activator for neutrophils, T cells, and other immune cells. The airway and respiratory epithelia play important roles in the initiation and modulation of inflammatory responses via production of cytokines and surfactant. The association between elevated levels of nitric oxide (NO) and IL-8 in acute lung injury associated with sepsis, acute respiratory distress syndrome, respiratory syncytial virus infection in infants, and other inflammatory diseases suggested that NO may play important roles in the control of IL-8 gene expression in the lung. We investigated the role of NO in the control of IL-8 gene expression in H441 lung epithelial cells. We found that a variety of NO donors significantly induced IL-8 mRNA levels, and the increase in IL-8 mRNA was associated with an increase in IL-8 protein. NO induction of IL-8 mRNA was due to increases in IL-8 gene transcription and mRNA stability. NO induction of IL-8 mRNA levels was not inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one and KT-5823, inhibitors of soluble guanylate cyclase and protein kinase G, respectively, and 8-bromo-cGMP did not increase IL-8 mRNA levels. This indicated that NO induces IL-8 mRNA levels independently of changes in the intracellular cGMP levels. NO induction of IL-8 mRNA was significantly reduced by inhibitors of extracellular regulated kinase and protein kinase C. IL-8 induction by NO was also reduced by hydroxyl radical scavengers such as dimethyl sulfoxide and dimethylthiourea, indicating the involvement of hydroxyl radicals in the induction process. NO induction of IL-8 gene expression could be a significant contributing factor in the initiation and induction of inflammatory response in the respiratory epithelium.

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A genetic CLOCK variant associated with cluster headache causing increased mRNA levels

Cephalalgia ◽

10.1177/0333102417698709 ◽

2017 ◽

Vol 38 (3) ◽

pp. 496-502 ◽

Cited By ~ 19

Author(s):

Carmen Fourier ◽

Caroline Ran ◽

Margret Zinnegger ◽

Anne-Sofie Johansson ◽

Christina Sjöstrand ◽

...

Keyword(s):

Gene Expression ◽

Circadian Rhythm ◽

Cluster Headache ◽

Clock Gene ◽

Control Sample ◽

Mrna Levels ◽

Nucleotide Polymorphisms ◽

Primary Fibroblast ◽

Clock Gene Expression ◽

Diurnal Preference

Background Cluster headache is characterized by recurrent unilateral headache attacks of severe intensity. One of the main features in a majority of patients is a striking rhythmicity of attacks. The CLOCK ( Circadian Locomotor Output Cycles Kaput) gene encodes a transcription factor that serves as a basic driving force for circadian rhythm in humans and is therefore particularly interesting as a candidate gene for cluster headache. Methods We performed an association study on a large Swedish cluster headache case-control sample (449 patients and 677 controls) screening for three single nucleotide polymorphisms (SNPs) in the CLOCK gene implicated in diurnal preference (rs1801260) or sleep duration (rs11932595 and rs12649507), respectively. We further wanted to investigate the effect of identified associated SNPs on CLOCK gene expression. Results We found a significant association with rs12649507 and cluster headache ( p = 0.0069) and this data was strengthened when stratifying for reported diurnal rhythmicity of attacks ( p = 0.0009). We investigated the effect of rs12649507 on CLOCK gene expression in human primary fibroblast cultures and identified a significant increase in CLOCK mRNA expression ( p = 0.0232). Conclusions Our results strengthen the hypothesis of the involvement of circadian rhythm in cluster headache.

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Alteration of Atrial Natriuretic Peptide and Brain Natriuretic Peptide Gene Expression Associated with Progression and Regression of Cardiac Hypertrophy in Renovascular Hypertensive Rats

Clinical Science ◽

10.1042/cs0900197 ◽

1996 ◽

Vol 90 (3) ◽

pp. 197-204 ◽

Cited By ~ 20

Author(s):

Hideo Kawakami ◽

Hideki Okayama ◽

Mareomi Hamada ◽

Kunio Hiwada

Keyword(s):

Gene Expression ◽

Atrial Natriuretic Peptide ◽

Cardiac Hypertrophy ◽

Brain Natriuretic Peptide ◽

Natriuretic Peptide ◽

Mrna Levels ◽

Hypertensive Rats ◽

Regression Of Cardiac Hypertrophy ◽

Peptide Gene ◽

Atrial Natriuretic

1. We assessed the changes of atrial natriuretic peptide and brain natriuretic peptide gene expression associated with progression and regression of cardiac hypertrophy in renovascular hypertensive rats (RHR). 2. Two-kidney, one-clip hypertensive rats (6-week-old male Wistar) were made and studied 6 (RHR-1) and 10 weeks (RHR-2) after the procedure. Regression of cardiac hypertrophy was induced by nephrectomy at 6 weeks after constriction, and the nephrectomized rats were maintained further for 4 weeks (nephrectomized rat: NEP). Sham operation was performed, and the rats were studied after 6 (Sham-1) and 10 weeks (Sham-2). Atrial natriuretic peptide and brain natriuretic peptide gene expression in the left ventricle was analysed by Northern blotting. 3. Plasma atrial natriuretic peptide and brain natriuretic peptide were significantly higher in RHR-1 and RHR-2 than in Sham-1, Sham-2 and NEP. Atrial natriuretic peptide and brain natriuretic peptide mRNA levels in RHR-1 were approximately 7.2-fold and 1.8-fold higher than those in Sham-1, respectively, and the corresponding levels in RHR-2 were 13.0-fold and 2.4-fold higher than those in Sham-2, respectively. Atrial natriuretic peptide and brain natriuretic peptide mRNA levels of NEP were normalized. Levels of atrial natriuretic peptide and brain natriuretic peptide mRNA were well correlated positively with left ventricular weight/body weight ratios. There was a significant positive correlation between the levels of atrial natriuretic peptide and brain natriuretic peptide mRNA (r = 0.86, P<0.01). 4. We conclude that the expression of atrial natriuretic peptide and brain natriuretic peptide genes is regulated in accordance with the degree of myocardial hypertrophy and that the augmented expression of these two natriuretic peptides may play an important role in the maintenance of cardiovascular haemodynamics in renovascular hypertension.

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Differential Effects of Gonadotropin-Releasing Hormone (GnRH) Pulse Frequency on Gonadotropin Subunit and GnRH Receptor Messenger Ribonucleic Acid Levels in Vitro*

Endocrinology ◽

10.1210/endo.138.3.4968 ◽

1997 ◽

Vol 138 (3) ◽

pp. 1224-1231 ◽

Cited By ~ 112

Author(s):

Ursula B. Kaiser ◽

Andrzej Jakubowiak ◽

Anna Steinberger ◽

William W. Chin

Keyword(s):

Gene Expression ◽

Messenger Rna ◽

Pulse Frequency ◽

Gnrh Receptor ◽

Pituitary Cells ◽

Mrna Levels ◽

Subunit Gene ◽

Differential Effects ◽

Messenger Ribonucleic Acid

Abstract The hypothalamic hormone, GnRH, is released and transported to the anterior pituitary in a pulsatile manner, where it binds to specific high-affinity receptors and regulates gonadotropin biosynthesis and secretion. The frequency of GnRH pulses changes under various physiological conditions, and varying GnRH pulse frequencies have been shown to regulate differentially the secretion of LH and FSH and the expression of the gonadotropin α, LHβ, and FSHβ subunit genes in vivo. We demonstrate differential effects of varying GnRH pulse frequency in vitro in superfused primary monolayer cultures of rat pituitary cells. Cells were treated with 10 nm GnRH pulses for 24 h at a frequency of every 0.5, 1, 2, or 4 h. α, LHβ, and FSHβ messenger RNA (mRNA) levels were increased by GnRH at all pulse frequencies. α and LHβ mRNA levels and LH secretion were stimulated to the greatest extent at a GnRH pulse frequency of every 30 min, whereas FSHβ mRNA levels and FSH secretion were stimulated maximally at a lower GnRH pulse frequency, every 2 h. GnRH receptor (GnRHR) mRNA levels also were increased by GnRH at all pulse frequencies and were stimulated maximally at a GnRH pulse frequency of every 30 min. Similar results were obtained when the dose of each pulse of GnRH was adjusted to maintain a constant total cumulative dose of GnRH over 24 h. These data show that gonadotropin subunit gene expression is regulated differentially by varying GnRH pulse frequencies in vitro, suggesting that the differential effects of varying GnRH pulse frequencies on gonadotropin subunit gene expression occur directly at the level of the pituitary. The pattern of regulation of GnRHR mRNA levels correlated with that of α and LHβ but was different from that of FSHβ. This suggests that α and LHβ mRNA levels are maximally stimulated when GnRHR levels are relatively high, whereas FSHβ mRNA levels are maximally stimulated at lower levels of GnRHR expression, and that the mechanism for differential regulation of the gonadotropins by varying pulse frequencies of GnRH may involve levels of GnRHR. Furthermore, these data suggest that the mechanisms whereby varying GnRH pulse frequencies stimulate α, LHβ, and GnRHR gene expression are similar, whereas the stimulation of FSHβ mRNA levels may be different.

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