scholarly journals Lipopolysaccharide enhances apoptosis of corpus luteum in isolated perfused bovine ovaries in vitro

Reproduction ◽  
2016 ◽  
Vol 151 (1) ◽  
pp. 17-28 ◽  
Author(s):  
J Lüttgenau ◽  
B Möller ◽  
D Kradolfer ◽  
O Wellnitz ◽  
R M Bruckmaier ◽  
...  

Lipopolysaccharide (LPS), the endotoxin of Gram-negative bacteria, has detrimental effects on the structure and function of bovine corpus luteum (CL)in vivo. The objective was to investigate whether these effects were mediated directly by LPS orviaLPS-induced release of PGF2α. Bovine ovaries with a mid-cycle CL were collected immediately after slaughter and isolated perfused for 240 min. After 60 min of equilibration, LPS (0.5 μg/ml) was added to the medium of five ovaries, whereas an additional six ovaries were not treated with LPS (control). After 210 min of perfusion, all ovaries were treated with 500 iu of hCG. In the effluent perfusate, concentrations of progesterone (P4) and PGF2αwere measured every 10 and 30 min, respectively. Punch biopsies of the CL were collected every 60 min and used for RT-qPCR to evaluate mRNA expression of receptors for LPS (TLR2,-4) and LH (LHCGR); the cytokineTNFA; steroidogenic (STAR,HSD3B), angiogenic (VEGFA121,FGF2), and vasoactive (EDN1) factors; and factors of prostaglandin synthesis (PGES,PGFS,PTGFR) and apoptosis (CASP3,-8,-9). Treatment with LPS abolished the hCG-induced increase in P4(P≤0.05); however, there was a tendency (P=0.10) for increased release of PGF2αat 70 min after LPS challenge. Furthermore, mRNA abundance ofTLR2,TNFA,CASP3,CASP8,PGES,PGFS, andVEGFA121increased (P≤0.05) after LPS treatment, whereas all other factors remained unchanged (P>0.05). In conclusion, reduced P4responsiveness to hCG in LPS-treated ovariesin vitrowas not due to reduced steroidogenesis, but was attributed to enhanced apoptosis. However, an impact of luteal PGF2αcould not be excluded.

2020 ◽  
Vol 64 (10) ◽  
Author(s):  
Sara E. Boyd ◽  
David M. Livermore ◽  
David C. Hooper ◽  
William W. Hope

ABSTRACT Modern medicine is threatened by the global rise of antibiotic resistance, especially among Gram-negative bacteria. Metallo-β-lactamase (MBL) enzymes are a particular concern and are increasingly disseminated worldwide, though particularly in Asia. Many MBL producers have multiple further drug resistances, leaving few obvious treatment options. Nonetheless, and more encouragingly, MBLs may be less effective agents of carbapenem resistance in vivo, under zinc limitation, than in vitro. Owing to their unique structure and function and their diversity, MBLs pose a particular challenge for drug development. They evade all recently licensed β-lactam–β-lactamase inhibitor combinations, although several stable agents and inhibitor combinations are at various stages in the development pipeline. These potential therapies, along with the epidemiology of producers and current treatment options, are the focus of this review.


mSystems ◽  
2018 ◽  
Vol 3 (6) ◽  
Author(s):  
Jingwei Cai ◽  
Robert G. Nichols ◽  
Imhoi Koo ◽  
Zachary A. Kalikow ◽  
Limin Zhang ◽  
...  

ABSTRACTThe gut microbiota is susceptible to modulation by environmental stimuli and therefore can serve as a biological sensor. Recent evidence suggests that xenobiotics can disrupt the interaction between the microbiota and host. Here, we describe an approach that combinesin vitromicrobial incubation (isolated cecal contents from mice), flow cytometry, and mass spectrometry- and1H nuclear magnetic resonance (NMR)-based metabolomics to evaluate xenobiotic-induced microbial toxicity. Tempol, a stabilized free radical scavenger known to remodel the microbial community structure and functionin vivo, was studied to assess its direct effect on the gut microbiota. The microbiota was isolated from mouse cecum and was exposed to tempol for 4 h under strict anaerobic conditions. The flow cytometry data suggested that short-term tempol exposure to the microbiota is associated with disrupted membrane physiology as well as compromised metabolic activity. Mass spectrometry and NMR metabolomics revealed that tempol exposure significantly disrupted microbial metabolic activity, specifically indicated by changes in short-chain fatty acids, branched-chain amino acids, amino acids, nucleotides, glucose, and oligosaccharides. In addition, a mouse study with tempol (5 days gavage) showed similar microbial physiologic and metabolic changes, indicating that thein vitroapproach reflectedin vivoconditions. Our results, through evaluation of microbial viability, physiology, and metabolism and a comparison ofin vitroandin vivoexposures with tempol, suggest that physiologic and metabolic phenotyping can provide unique insight into gut microbiota toxicity.IMPORTANCEThe gut microbiota is modulated physiologically, compositionally, and metabolically by xenobiotics, potentially causing metabolic consequences to the host. We recently reported that tempol, a stabilized free radical nitroxide, can exert beneficial effects on the host through modulation of the microbiome community structure and function. Here, we investigated a multiplatform phenotyping approach that combines high-throughput global metabolomics with flow cytometry to evaluate the direct effect of tempol on the microbiota. This approach may be useful in deciphering how other xenobiotics directly influence the microbiota.


2020 ◽  
Vol 34 (1) ◽  
pp. 104-114 ◽  
Author(s):  
Guosong Xin ◽  
Miao Yu ◽  
Yang Hu ◽  
Shiyong Gao ◽  
Zheng Qi ◽  
...  

Reproduction ◽  
2015 ◽  
Vol 150 (3) ◽  
pp. 217-225 ◽  
Author(s):  
Koumei Shirasuna ◽  
Haruka Matsumoto ◽  
Shuichi Matsuyama ◽  
Koji Kimura ◽  
Heinrich Bollwein ◽  
...  

When pregnancy is established, interferon tau (IFNT), a well-known pregnancy recognition signal in ruminants, is secreted by embryonic trophoblast cells and acts within the uterus to prepare for pregnancy. IFNT acts as an endocrine factor on the corpus luteum (CL) to induce refractory ability against the luteolytic action of PGF2α. Hypothesising that IFNT may influence not only the uterine environment but also the CL in cows via local or peripheral circulation, we investigated qualitative changes in the CL of pregnant cows during the maternal recognition period (day 16) and the CL of non-pregnant cows. The CL of pregnant animals had a higher number of neutrophils, and the expression of interleukin 8 (IL8) mRNA and its protein was higher as well as compared with the CL of non-pregnant animals. Although IFNT did not affect progesterone (P4) secretion and neutrophil migration directly, it stimulated IL8 mRNA expression on luteal cells (LCs), influencing the neutrophils, resulting in the increased migration of IFNT-activated neutrophils. Moreover, both IFNT-activated neutrophils and IL8 increased P4 secretion from LCs in vitro. Our novel finding was the increase in neutrophils and IL8 within the CL of pregnant cows, suggesting the involvement of IFNT function within the CL toward establishment of pregnancy in cows. The present results suggest that IFNT upregulates neutrophil numbers and function via IL8 on LCs in the CL of early pregnant cows and that both neutrophils and IL8, stimulated by IFNT, are associated with an increase in P4 concentrations during the maternal recognition period in cows.


2020 ◽  
Vol 21 (9) ◽  
pp. 3302
Author(s):  
Małgorzata Zimowska ◽  
Karolina Archacka ◽  
Edyta Brzoska ◽  
Joanna Bem ◽  
Areta M. Czerwinska ◽  
...  

Skeletal muscle regeneration depends on the satellite cells, which, in response to injury, activate, proliferate, and reconstruct damaged tissue. However, under certain conditions, such as large injuries or myopathies, these cells might not sufficiently support repair. Thus, other cell populations, among them adipose tissue-derived stromal cells (ADSCs), are tested as a tool to improve regeneration. Importantly, the pro-regenerative action of such cells could be improved by various factors. In the current study, we tested whether IL-4 and SDF-1 could improve the ability of ADSCs to support the regeneration of rat skeletal muscles. We compared their effect at properly regenerating fast-twitch EDL and poorly regenerating slow-twitch soleus. To this end, ADSCs subjected to IL-4 and SDF-1 were analyzed in vitro and also in vivo after their transplantation into injured muscles. We tested their proliferation rate, migration, expression of stem cell markers and myogenic factors, their ability to fuse with myoblasts, as well as their impact on the mass, structure and function of regenerating muscles. As a result, we showed that cytokine-pretreated ADSCs had a beneficial effect in the regeneration process. Their presence resulted in improved muscle structure and function, as well as decreased fibrosis development and a modulated immune response.


2017 ◽  
Vol 44 (3) ◽  
pp. 907-919 ◽  
Author(s):  
Qiang Liu ◽  
Deyi Luo ◽  
Tongxin Yang ◽  
Banghua Liao ◽  
Hong Li ◽  
...  

Background/Aims: Overactive bladder associated with bladder outlet obstruction (BOO) is a highly prevalent condition, which is usually treated with antimuscarinics. However, the potential effects of antimuscarinics on the structure and function of bladder have not been investigated thus far. Methods: Sprague-Dawley(R) rats accepted bladder neck obstruction surgery or sham surgery, and then received treatment of three different antimuscarinics (Solifenacin, Darifenacin, and Tolterodine) or vehicle. After 3, 6 and 12 weeks, the bladder function and structure were measured. The effect of antimuscarinics on cellular alteration in vitro was observed under mechanical stimulation. Bladder morphology were examined by immunohistochemistry, and the bladder function were investigated by cystometry and strip contractility test. The expression of muscarinic receptors and inflammatory cytokines were measured by PCR and Western blotting. Results: Here we demonstrate, both in vitro and in vivo, that antimuscarinics are protective regulators for the bladder structure and function. Antimuscarinics decrease the weight of bladders with BOO. Antimuscarinics improve the voiding parameter and enhance the contraction of bladder smooth muscle. The results also show that antimuscarinics inhibit the proliferation of bladder smooth muscle cells both in vivo and in vitro, it can reduce the collagen deposition and inflammatory cytokines in bladders with BOO. During this process, the expression of M2 and M3 receptors was altered by antimuscarinics. Conclusion: Antimuscarinics could reverse the structural and functional changes of BOO bladder wall at cellular and tissue level, and the alteration of M2 and M3 receptors may be involved in this biological process.


1996 ◽  
Vol 132 (3) ◽  
pp. 335-344 ◽  
Author(s):  
H Aizawa ◽  
K Sutoh ◽  
I Yahara

Cofilin is a low molecular weight actin-modulating protein whose structure and function are conserved among eucaryotes. Cofilin exhibits in vitro both a monomeric actin-sequestering activity and a filamentous actin-severing activity. To investigate in vivo functions of cofilin, cofilin was overexpressed in Dictyostelium discoideum cells. An increase in the content of D. discoideum cofilin (d-cofilin) by sevenfold induced a co-overproduction of actin by threefold. In cells over-expressing d-cofilin, the amount of filamentous actin but not that of monomeric actin was increased. Overexpressed d-cofilin co-sedimented with actin filaments, suggesting that the sequestering activity of d-cofilin is weak in vivo. The overexpression of d-cofilin increased actin bundles just beneath ruffling membranes where d-cofilin was co-localized. The overexpression of d-cofilin also stimulated cell movement as well as membrane ruffling. We have demonstrated in vitro that d-cofilin transformed latticework of actin filaments cross-linked by alpha-actinin into bundles probably by severing the filaments. D. discoideum cofilin may sever actin filaments in vivo and induce bundling of the filaments in the presence of cross-linking proteins so as to generate contractile systems involved in membrane ruffling and cell movement.


2020 ◽  
Author(s):  
R Christian McDonald ◽  
Matthew J Schott ◽  
Temitope A Idowu ◽  
Peter J Lyons

Abstract Background. Like most major enzyme families, the M14 family of metallocarboxypeptidases (MCPs) contains a number of pseudoenzymes predicted to lack enzyme activity and with poorly characterized molecular function. The genome of the yeast Saccharomyces cerevisiae encodes one member of the M14 MCP family, a pseudoenzyme named Ecm14 proposed to function in the extracellular matrix. In order to better understand the function of such pseudoenzymes, we studied the structure and function of Ecm14 in S. cerevisiae. Results. A phylogenetic analysis of Ecm14 in fungi found it to be conserved throughout the ascomycete phylum, with a group of related pseudoenzymes found in basidiomycetes. To investigate the structure and function of this conserved protein, His6-tagged Ecm14 was overexpressed in Sf9 cells and purified. The prodomain of Ecm14 was cleaved in vivo and in vitro by endopeptidases, suggesting an activation mechanism; however, no activity was detectable using standard carboxypeptidase substrates. In order to determine the function of Ecm14 using an unbiased screen, we undertook a synthetic lethal assay. Upon screening approximately 27,000 yeast colonies, twenty-two putative synthetic lethal clones were identified. Further analysis showed many to be synthetic lethal with auxotrophic marker genes and requiring multiple mutations, suggesting that there are few, if any, single S. cerevisiae genes that present synthetic lethal interactions with ecm14Δ. Conclusions. We show in this study that Ecm14, although lacking detectable enzyme activity, is a conserved carboxypeptidase-like protein that is secreted from cells and is processed to a mature form by the action of an endopeptidase. Our study and datasets from other recent large-scale screens suggest a role for Ecm14 in processes such as vesicle-mediated transport and aggregate invasion, a fungal process that has been selected against in modern laboratory strains of S. cerevisiae.


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