Oral Metformin Treatment Counteracts Adipoinsular Axis Dysfunction in Hypothalamic Obese Rats

Rats neonatally treated with monosodium L-glutamate (MSG) are deeply dysfunctional in adulthood. We explored the effect of an oral low dose of metformin treatment in male MSG rats on adipoinsular axis and visceral adipose tissue (VAT) dysfunctions, in both basal (nonfasting) and endotoxemia conditions. MSG rats, treated or not treated with metformin (30 days prior to experimentation), and control litter-mates (CTR) were studied at 90 days of age. Peripheral concentrations of glucose, lipids, and hormones were determined in basal and post-lipopolysaccharide (LPS) treatment conditions. Food intake and body weight (BW) were recorded and VAT mass and leptin mRNA levels were evaluated. Data indicated that MSG rats were lighter and displayed hypercorticosteronemia, hypophagia, adipoinsular axis hyperactivity, and enhanced VAT mass associated with an increased leptin gene expression. Interestingly, metformin-treated MSG rats corrected BW catch-up and counteracted VAT (mass and leptin mRNA level) and adipoinsular axis (basal and post-LPS) dysfunctions. Thus metformin treatment in MSG rats is able to correct several VAT and metabolic-endocrine dysfunctions. Our study suggests that a low-dose metformintherapy is effective to correct, at least in part, adipoinsular axis dysfunction in hypertrophic obese phenotypes, such as that of the human Cushing syndrome.

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Syk Plays a Critical Role in the Expression and Activation of IRAK1 in LPS-Treated Macrophages

Mediators of Inflammation ◽

10.1155/2017/1506248 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Jae Gwang Park ◽

Young-Jin Son ◽

Byong Chul Yoo ◽

Woo Seok Yang ◽

Ji Hye Kim ◽

...

Keyword(s):

Tyrosine Kinase ◽

Protein Tyrosine Kinase ◽

Interleukin 1 ◽

Mrna Level ◽

Critical Role ◽

Primary Response ◽

Transcriptional Level ◽

Mrna Levels ◽

Treatment Conditions ◽

Lps Treatment

To address how interleukin-1 receptor-associated kinase 1 (IRAK1) is controlled by other enzymes activated by toll-like receptor (TLR) 4, we investigated the possibility that spleen tyrosine kinase (Syk), a protein tyrosine kinase that is activated at an earlier stage during TLR4 activation, plays a central role in regulating the functional activation of IRAK1. Indeed, we found that overexpression of myeloid differentiation primary response gene 88 (MyD88), an adaptor molecule that drives TLR signaling, induced IRAK1 expression and that piceatannol, a Syk inhibitor, successfully suppressed the MyD88-dependent upregulation of IRAK1 under LPS treatment conditions. Interestingly, in Syk-knockout RAW264.7 cells, IRAK1 activity was almost completely blocked after LPS treatment, while providing a Syk-recovery gene to the knockout cells successfully restored IRAK1 expression. According to our measurements of IRAK1 mRNA levels, the transcriptional upregulation of IRAK1 was induced by LPS treatment between 4 and 60 min, and this can be suppressed in Syk knockout cells, providing an effect similar that that seen under piceatannol treatment. The overexpression of Syk reverses this effect and leads to a significantly higher IRAK1 mRNA level. Collectively, our results strongly suggest that Syk plays a critical role in regulating both the activity and transcriptional level of IRAK1.

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Increased NOX1 and DOUX2 Expression in the Colonic Mucosa of Patients with Chronic Functional Constipation

10.21203/rs.3.rs-643716/v1 ◽

2021 ◽

Author(s):

Xiuqin Wei ◽

Chunbo Kang ◽

Lei Gao ◽

Mengqiao Zhang ◽

Mei Xue ◽

...

Keyword(s):

Nadph Oxidase ◽

Healthy Subjects ◽

Mrna Level ◽

Functional Constipation ◽

Inflammatory Cells ◽

Histological Structure ◽

Mrna Levels ◽

Significant Difference ◽

And Control ◽

Colonic Biopsies

Abstract Aim To determine whether oxidative stress and inflammation are associated with constipation by examining the expression of the main producers of reactive oxygen species, NADPH oxidases, and pro-inflammatory cytokines in the colon of patients with chronic functional constipation. Methods The colonic biopsies were collected from 32 patients with chronic functional constipation and 30 healthy subjects who underwent colonoscopy. Colonic mucosal histology was observed. IL-1β, IL-6, IL-8 mRNA, and four members of NADPH oxidase (NOX1, NOX2, DOUX2 and NOX4) protein and mRNA were assessed by immunohistochemistry, western blotting and RT-PCR. Results The tissues from both patients and healthy subjects showed normal histological structure without increase of inflammatory cells. NOX1 protein and mRNA levels were significantly increased compared to controls (P<0.05). DOUX2 protein, but not mRNA, was increased by twofold compared to controls (P<0.05). The levels of NOX2 and NOX4 protein and mRNA demonstrated no significant difference between patients and control subjects. The levels of IL-1β and IL-6 mRNA were significantly higher in constipation patients (P<0.05), while IL-8 mRNA level was no different between the two groups. Conclusion NADPH oxidase and pro-inflammatory cytokine might be involved in the pathogeneses of chronic functional constipation.

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Reduced miR-26b Expression in Megakaryocytes and Platelets Contributes to Elevated Level of Platelet Activation Status in Sepsis

International Journal of Molecular Sciences ◽

10.3390/ijms21030866 ◽

2020 ◽

Vol 21 (3) ◽

pp. 866 ◽

Cited By ~ 5

Author(s):

Bernadett Szilágyi ◽

Zsolt Fejes ◽

Szilárd Póliska ◽

Marianna Pócsi ◽

Zsolt Czimmerer ◽

...

Keyword(s):

Platelet Activation ◽

Mirna Expression ◽

Mrna Level ◽

Severe Infection ◽

Mrna Levels ◽

Rna Seq ◽

Calpain Inhibition ◽

The Impact ◽

Lps Treatment ◽

Activation Status

In sepsis, platelets may become activated via toll-like receptors (TLRs), causing microvascular thrombosis. Megakaryocytes (MKs) also express these receptors; thus, severe infection may modulate thrombopoiesis. To explore the relevance of altered miRNAs in platelet activation upon sepsis, we first investigated sepsis-induced miRNA expression in platelets of septic patients. The effect of abnormal Dicer level on miRNA expression was also evaluated. miRNAs were profiled in septic vs. normal platelets using TaqMan Open Array. We validated platelet miR-26b with its target SELP (P-selectin) mRNA levels and correlated them with clinical outcomes. The impact of sepsis on MK transcriptome was analyzed in MEG-01 cells after lipopolysaccharide (LPS) treatment by RNA-seq. Sepsis-reduced miR-26b was further studied using Dicer1 siRNA and calpain inhibition in MEG-01 cells. Out of 390 platelet miRNAs detected, there were 121 significantly decreased, and 61 upregulated in sepsis vs. controls. Septic platelets showed attenuated miR-26b, which were associated with disease severity and mortality. SELP mRNA level was elevated in sepsis, especially in platelets with increased mean platelet volume, causing higher P-selectin expression. Downregulation of Dicer1 generated lower miR-26b with higher SELP mRNA, while calpeptin restored miR-26b in MEG-01 cells. In conclusion, decreased miR-26b in MKs and platelets contributes to an increased level of platelet activation status in sepsis.

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Low Dose Administration of Glutamate Triggers a Non-Apoptotic, Autophagic Response in PC12 Cells

Cellular Physiology and Biochemistry ◽

10.1159/000430250 ◽

2015 ◽

Vol 37 (5) ◽

pp. 1750-1758 ◽

Cited By ~ 7

Author(s):

Eleni Stamoula ◽

Theofanis Vavilis ◽

Eleni Aggelidou ◽

Aikaterini Kaidoglou ◽

Angeliki Cheva ◽

...

Keyword(s):

Pc12 Cells ◽

Cell Fate ◽

Low Dose ◽

Mrna Level ◽

Neuronal Cell ◽

Cellular Level ◽

Mrna Levels ◽

Protein Levels ◽

Low Concentrations ◽

Discrete Effect

Background/Aims: Increasing amounts of the neurotransmitter glutamate are associated with excitotoxicity, a phenomenon related both to homeostatic processes and neurodegenerative diseases such as multiple sclerosis. Methods: PC12 cells (rat pheochromocytoma) were treated with various concentrations of the non-essential amino acid glutamate for 0.5-24 hours. The effect of glutamate on cell morphology was monitored with electron microscopy and haematoxylin-eosin staining. Cell survival was calculated with the MTT assay. Expression analysis of chaperones associated with the observed phenotype was performed using either Western Blotting at the protein level or qRT-PCR at the mRNA level. Results: Administration of glutamate in PC12 cells in doses as low as 10 μM causes an up-regulation of GRP78, GRP94 and HSC70 protein levels, while their mRNA levels show the opposite kinetics. At the same time, GAPDH and GRP75 show reduced protein levels, irrespective of their transcriptional rate. On a cellular level, low concentrations of glutamate induce an autophagy-mediated pro-survival phenotype, which is further supported by induction of the autophagic marker LC3. Conclusion: The findings in the present study underline a discrete effect of glutamate on neuronal cell fate depending on its concentration. It was also shown that a low dose of glutamate orchestrates a unique expression signature of various chaperones and induces cell autophagy, which acts in a neuroprotective fashion.

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Reproductive responses of the male Brandt’s vole, Lasiopodomys brandtii (Rodentia: Cricetidae) to tannic acid

Zoologia (Curitiba) ◽

10.3897/zoologia.37.e52232 ◽

2020 ◽

Vol 37 ◽

pp. 1-11

Author(s):

Xin Dai ◽

Ling-Yu Zhou ◽

Ting-Ting Xu ◽

Qiu-Yue Wang ◽

Bin Luo ◽

...

Keyword(s):

Tannic Acid ◽

Low Dose ◽

Mrna Level ◽

Regulatory Protein ◽

Antioxidant Properties ◽

Sperm Concentration ◽

High Dose ◽

Mrna Levels ◽

Pubertal Stage ◽

Lasiopodomys Brandtii

Tannins are polyphenols that are present in various plants, and potentially contain antioxidant properties that promote reproduction in animals. This study investigated how tannic acid (TA) affects the reproductive parameters of male Brandt’s voles, Lasiopodomys brandtii (Radde, 1861). Specifically, the anti-oxidative level of serum, autophagy in the testis, and reproductive physiology were assessed in males treated with TA from the pubertal stage. Compared to the control, low dose TA enhanced relative testis and epididymis weight and sperm concentration in the epididymis, and significantly increased the level of serum superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). mRNA levels of autophagy related genes LC3 and Beclin1 decreased significantly with low dose TA compared to the control. However, compared to the control, high dose TA sharply reduced the levels of serum SOD, GSH-Px, CAT, serum testosterone (T), and mRNA level in steroidogenic acute regulatory protein (StAR) in the testis. Both sperm abnormality and mortality increased with high dose TA compared to the control and low dose TA. Collectively, this study demonstrated that TA treatment during puberty had a dose-dependent effect on the reproductive responses of male Brandt’s voles. TA might mediate autophagy in the testis, through both indirect and direct processes. TA mainly affected the reproductive function of male Brandt’s voles by regulating anti-oxidative levels. This study advances our understanding of the mechanisms by which tannins influence reproduction in herbivores.

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Intraperitoneal insulin is more potent than subcutaneous insulin at restoring hepatic insulin-like growth factor-I mRNA levels in the diabetic rat: a functional role for the portal vascular link

Journal of Molecular Endocrinology ◽

10.1677/jme.0.0090257 ◽

1992 ◽

Vol 9 (3) ◽

pp. 257-263 ◽

Cited By ~ 25

Author(s):

D. L. Russell-Jones ◽

M. Rattray ◽

V. J. Wilson ◽

R. H. Jones ◽

P. H. Sönksen ◽

...

Keyword(s):

Blood Glucose ◽

Low Dose ◽

Mrna Level ◽

Diabetic Rats ◽

Hormonal Control ◽

Diabetic Rat ◽

High Dose ◽

Mrna Levels ◽

Igf I ◽

Intraperitoneal Insulin

ABSTRACT There is evidence that the hormonal control of hepatic IGF-I production is mediated by GH and insulin. To elucidate the role of these hormones further we administered s.c. or i.p. insulin (at 2·5 and 5·0 IU/day) and/or GH (0·8 IU/day) to rats made diabetic with streptozotocin 16 days previously. Hepatic IGF-I production was then assessed by quantifying hepatic IGF-I mRNA levels by autoradiography of Northern blots. Diabetes resulted in a fivefold reduction in hepatic IGF-I mRNA levels (optical density (OD) of the 0·7–1·1 kb band: controls, 1·3±0·09; diabetics, 0·28±0·08; P<0·01), which was not significantly changed by treatment with s.c. insulin (OD: low dose, 0·55±0·05; high dose, 0·58±0·05) or low dose i.p. insulin (OD: 0·40±0·03). High dose i.p. insulin enhanced hepatic IGF-I mRNA levels (OD: 0·93±0·23) compared with diabetic rats (P<0·01) and those given high dose s.c. insulin (P<0·04), despite the blood glucose values being similar in the treated groups (i.p., 4·72±0·29 mmol/l; s.c., 3·32±0·03 mmol/l). Administration of GH alone partially restored the hepatic IGF-I mRNA level (OD: GH-treated, 1·00±0·05; diabetic, 0·28±0·08; P<0·01), whilst having no effect on blood glucose values (diabetic, 36·35±0·45 mmol/l; GH-treated, 38·65±2·39 mmol/l). Additional administration of s.c. insulin completely restored IGF-I mRNA levels to those of controls (OD: low dose, 1·35±0·14; high dose, 1·27 ± 0·18). These observations indicate that insulin and GH are required for full expression of hepatic IGF-I mRNA and that insulin given i.p. is more potent than that given s.c. at stimulating hepatic synthesis of IGF-I.

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Cancer cachexia differentially regulates visceral adipose tissue turnover

Journal of Endocrinology ◽

10.1530/joe-16-0305 ◽

2017 ◽

Vol 232 (3) ◽

pp. 493-500 ◽

Cited By ~ 9

Author(s):

Felipe de Oliveira Franco ◽

Magno Alves Lopes ◽

Felipe dos Santos Henriques ◽

Rodrigo Xavier das Neves ◽

Cesário Bianchi Filho ◽

...

Keyword(s):

Adipose Tissue ◽

Cancer Cachexia ◽

Stromal Vascular Fraction ◽

Body Weight Loss ◽

Early Event ◽

Mrna Levels ◽

Adipose Tissue Depots ◽

Cellular Turnover ◽

Visceral Adipose ◽

And Control

Cancer cachexia (CC) is a progressive metabolic syndrome that is marked by severe body weight loss. Metabolic disarrangement of fat tissues is a very early event in CC, followed by adipose tissue (AT) atrophy and remodelling. However, there is little information regarding the possible involvement of cellular turnover in this process. Thus, in this study, we evaluated the effect of CC on AT turnover and fibrosis of mesenteric (MEAT) and retroperitoneal (RPAT) adipose tissue depots as possible factors that contribute to AT atrophy. CC was induced by a subcutaneous injection of Walker tumour cells (2 × 107) in Wistar rats, and control animals received only saline. The experimental rats were randomly divided into four experimental groups: 0 days, 4 days, 7 days and 14 days after injection. AT turnover was analysed according to the Pref1/Adiponectin ratio of gene expression from the stromal vascular fraction and pro-apoptotic CASPASE3 and CASPASE9 from MEAT and RPAT. Fibrosis was verified according to the total collagen levels and expression of extracellular matrix genes. AT turnover was verified by measurements of lipolytic protein expression. We found that the Pref1/Adiponectin ratio was decreased in RPAT (81.85%, P < 0.05) with no changes in MEAT compared with the respective controls. CASPASE3 and CASPASE9 were activated on day 14 only in RPAT. Collagen was increased on day 7 in RPAT (127%) and MEAT (4.3-fold). The Collagen1A1, Collagen3A1, Mmp2 and Mmp9 mRNA levels were upregulated only in MEAT in CC. Lipid turnover was verified in RPAT and was not modified in CC. We concluded that the results suggest that CC affects RPAT cellular turnover, which may be determinant for RPAT atrophy.

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PL-002 AGTR1 polymorphism is associated with elite endurance athletes: A functional study

Exercise Biochemistry Review ◽

10.14428/ebr.v1i1.8063 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Xiaolin Yang ◽

Yang Hu ◽

Yanchun Li ◽

Tao Mei ◽

Lijing Gong

Keyword(s):

Mrna Level ◽

Endurance Athletes ◽

Aerobic Performance ◽

Functional Study ◽

Genotype Distribution ◽

Mrna Levels ◽

Angiotensin Ii Receptor ◽

Control Subjects ◽

Genotype Frequencies ◽

And Control

Objective To explore the association between the polymorphism of angiotensin II receptor type 1 gene(AGTR1) and elite endurance athlete performance and the mechanism of how the polymorphism works. Methods (1) Polymorphism of AGTR1 rs5182 between 122 elite Chinese endurance athletes and 222 controls were analyzed by MALDI-TOF-MS. (2) Aerobic capacity of 79 elite Chinese endurance athletes such as VC/FEV1/MVV/ VO2AT/ HRAT/ VAT/ VO2max/ HRmax/ VVO2max were measured and association between rs5182 polymorphism and the performance was analyzed. (3) PcDNA3.1-AGTR1 -T and pcDNA3.1-AGTR1-C plasmid were build and the plasmids was transfected into mammalian 293T cells. mRNA levels were detected after 48 hours. Statistical analysis was performed using SPSS software version 15.0. Values of P < 0.05 were considered statistically significant. Continuous data were expressed as mean ± SD, while categorical data were expressed as frequencies. Genotype distribution and allele frequencies between athletes and control subjects were compared using χ2 tests. Aerobic performance data was analyzed with One-Way ANOVA if it conformed to normal distribution and homogeneity of variance otherwise Non-parametric test of independent sample was used. Results (1) Genotype frequencies of AGTR1 rs5182 are significant differences between the athletes and control subjects (p = 0.040), the Word-Class athletes and control subjects (p = 0.018), 5km athletes and control subjects (p =0.015), 10km athletes and control subjects (p = 0.026), male athletes and male controls(p=0.045). (2) Association is found between Genotype distribution and MV(L/min) though others not (Genotype: MV; CC: 122.514±6.767; CT:117.187±17.961; TT:119.688±20.226, p=0.047). (3) Transiently transfectedpcDNA3.1-AGTR1-T and pcDNA3.1-AGTR1-C plasmids into 293T cells successfully. The differences of mRNA levels between the groups were not significant (p = 0.991). Conclusions AGTR1 gene rs5182 could be a candidate genetic mark of selection elite endurance athletes in Han Population from Northern China, but this polymorphism does not affect AT1R protein function through changing its mRNA level.

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The cellular basis of compensatory muscle growth in the teleost Odontesthes bonariensis

Journal of Experimental Biology ◽

10.1242/jeb.242567 ◽

2021 ◽

Author(s):

Ignacio Simó ◽

Mariano Faggiani ◽

Daniel A. Fernandez ◽

Andrés A. Sciara ◽

Silvia E. Arranz

Keyword(s):

Cell Proliferation ◽

Mrna Level ◽

Muscle Growth ◽

Mrna Levels ◽

Experimental Conditions ◽

Cross Sectional ◽

Cellular Basis ◽

Odontesthes Bonariensis ◽

Catch Up

This study evaluates white muscle growth and in vivo cell proliferation during a fasting and refeeding trial, using pejerrey Odontesthes bonariensis as animal model, in order to better understand the cellular basis governing catch-up growth. Experiments consisted in two groups of fish, a control one continuously fed ad libitum, and a group fasted for 2 weeks and then fed for another 2 weeks. We examined how the formation of new muscle fibers and their increase in size were related to muscle precursor cell (MPC) proliferation under both experimental conditions. During fasting, the number of 5-ethynyl-2'-deoxyuridinepositive (EdU+) cells decreased along with myogenic regulatory factors (MRF) mRNA levels related to myoblast proliferation and differentiation, and the muscle stem cell-markerPax7 mRNA level increased. Analysis of myomere cross-sectional area, distribution of muscle fiber sizes and number of fibers per myomere showed that muscle hypertrophy but not hyperplasia was inhibited during fasting. Both higher igf2 mRNA level and the persistence of cell proliferation could be supporting new myofibre formation. On the other hand, an exacerbated MPC proliferation occurred during catch-up growth, and this increase in cell number could be contributing to the growth of both pre-existing and newly form small fibers. The finding that some MPCs proliferate during fasting and that muscle growth mechanisms, hyperplasia and hypertrophy, are differentially regulated could help to explain why re-fed fish could growth at higher rates, and why they return to the lost growth trajectory.

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Expression of the glucose transporter GLUT4 in the muscular dystrophic mdx mouse

Biochemical Journal ◽

10.1042/bj2910257 ◽

1993 ◽

Vol 291 (1) ◽

pp. 257-261 ◽

Cited By ~ 12

Author(s):

C Olichon-Berthe ◽

N Gautier ◽

E Van Obberghen ◽

Y Le Marchand-Brustel

Keyword(s):

Skeletal Muscle ◽

Plasma Membranes ◽

Glucose Transporter ◽

Mrna Level ◽

Mdx Mouse ◽

Mdx Mice ◽

Mrna Levels ◽

Skeletal Tissue ◽

Muscle Tissues ◽

And Control

Glucose transporter protein levels have been investigated in mdx and control (C57Bl/10) mice. Crude membrane fractions (microsomes plus plasma membranes) were prepared from skeletal muscle, heart, diaphragm and brain of 5-6-week-old and 6-7-month-old control and mdx mice. Using Western blot analysis with C-terminal-specific anti-peptide antibodies, we investigated the glucose transporters GLUT4 in the different muscle tissues and GLUT1 in brain. In skeletal tissue from the hindlegs, GLUT4 was increased by approximately 55% in mdx mice compared with control mice at both ages studied. In the diaphragm, the amount of GLUT4 protein was unchanged in young mdx mice, and was decreased by 37.4 +/- 4.7% in older mice compared with age-matched control mice. No difference was observed between mdx and control mice in the amounts of GLUT4 and GLUT1 in heart and brain preparations respectively. To determine whether the change in GLUT4 protein observed in the diaphragm and skeletal muscle of mdx mice was regulated through changes at the level of glucose transporter mRNA, Northern blot analyses were performed. In skeletal muscle, GLUT4 mRNA level per tissue was not different between the two groups of mice at both ages studied. In contrast, the decrease in the amount of GLUT4 protein observed in the diaphragm of 6-7-month-old mdx mice was accompanied by a decrease in the GLUT4 mRNA level. In conclusion, the levels of GLUT4 protein were modified in muscle tissues from mdx compared with control mice, and these modifications were different depending on the muscle involved and the age of the mice. An increase in the amount of GLUT4 protein in the skeletal muscle of mdx mice was not due to changes at the mRNA level. The diaphragms of 6-7-month-old mdx mice exhibited decreases in GLUT4 protein and mRNA levels that were not detected in young animals (5-6 weeks old).

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