PPAR beta/delta regulates the immune response mechanisms in the porcine endometrium during LPS-induced inflammation - An in vitro study.

Inflammation in the reproductive tract has become a serious threat to animal fertility. Recently, the role of peroxisome proliferator-activated receptor gamma (PPARγ) in the context of reproduction and the inflammatory response has been highlighted, but the role of PPARß/δ has not been fully elucidated. The aim of the present study was to investigate the in vitro effect of PPARß/δ ligands (agonist: L-165,041 and antagonist: GSK 3787) on the transcriptome profile of porcine endometrium during LPS-induced inflammation in the mid-luteal and follicular phases of the oestrous cycle (days 10-12 and 18-20, respectively) using the RNA-Seq method. During the mid-luteal phase of the oestrous cycle, the current study identified 145 and 143 differentially expressed genes (DEGs) after treatment with an agonist or antagonist, respectively. During the follicular phase of the oestrous cycle, 55 and 207 DEGs were detected after treatment with an agonist or antagonist, respectively. The detected DEGs are engaged in the regulation of various processes, such as the complement and coagulation cascade, NF-κB signalling pathway, or the pathway of 15-eicosatetraenoic acid derivatives synthesis. The results of the current study indicate that PPARß/δ ligands are involved in the control of the endometrial inflammatory response.

New insights into the potential effects of PET microplastics on organisms via extracellular vesicle-mediated communication.

Plastics have become an integral part of our daily lives. In the environment, plastics break down into small pieces (<5 mm) that are referred to as microplastics. Microplastics are ubiquitous and widespread in the environment, and all living organisms are exposed to their effects. The present study provides new insights into the potential effects of polyethylene terephthalate (PET) microplastics on organisms via extracellular vesicle (EV)-mediated communication. The study demonstrated that serum-derived EVs are able to transport plastic particles. In addition, PET microplastics alter the content of miRNA in EVs. The identified differentially regulated miRNAs may target genes associated with lifestyle diseases, such as cardiovascular or metabolic diseases, and carcinogenesis. This work expands our understanding of PET microplastics' effects on organisms via EV-mediated communication and identifies directions for further research and strategies.

PPARß/δ Ligands Regulate Oxidative Status and Inflammatory Response in Inflamed Corpus Luteum-An In Vitro Study.

Inflammation in the female reproductive system causes serious health problems including infertility. The aim of this study was to determine the in vitro effects of peroxisome proliferator-activated receptor-beta/delta (PPARß/δ) ligands on the transcriptomic profile of the lipopolysaccharide (LPS)-stimulated pig corpus luteum (CL) in the mid-luteal phase of the estrous cycle using RNA-seq technology. The CL slices were incubated in the presence of LPS or in combination with LPS and the PPARß/δ agonist-GW0724 (1 µmol/L or 10 µmol/L) or the antagonist-GSK3787 (25 µmol/L). We identified 117 differentially expressed genes after treatment with LPS; 102 and 97 differentially expressed genes after treatment, respectively, with the PPARß/δ agonist at a concentration of 1 µmol/L or 10 µmol/L, as well as 88 after the treatment with the PPARß/δ antagonist. In addition, biochemical analyses of oxidative status were performed (total antioxidant capacity and activity of peroxidase, catalase, superoxide dismutase, and glutathione S-transferase). This study revealed that PPARß/δ agonists regulate genes involved in the inflammatory response in a dose-dependent manner. The results indicate that the lower dose of GW0724 showed an anti-inflammatory character, while the higher dose seems to be pro-inflammatory. We propose that GW0724 should be considered for further research to alleviate chronic inflammation (at the lower dose) or to support the natural immune response against pathogens (at the higher dose) in the inflamed corpus luteum.

In vitro effects of PPAR gamma ligands on gene expression in corpus luteum explants in non-pregnant pigs - Transcriptome analysis.

The corpus luteum (CL) is a temporary endocrine structure in the female ovaries that develops cyclically in mature females during luteinization. This study aimed to determine the in vitro effects of peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the transcriptomic profile of the porcine CL in the mid- and late-luteal phase of the estrous cycle using RNA-seq technology. The CL slices were incubated in the presence of PPARγ agonist - pioglitazone or antagonist - T0070907. We identified 40 differentially expressed genes after treatment with pioglitazone and 40 after treatment with T0070907 in the mid-luteal phase as well as 26 after pioglitazone and 29 after T0070907 treatment in the late-luteal phase of the estrous cycle. In addition, we detected differences in gene expression between the mid- and late-luteal phase without treatment (409 differentially expressed genes). This study revealed a number of novel candidate genes that may play a role in controlling the function of CL by regulating signaling pathways related to ovarian steroidogenesis, metabolic processes, cell differentiation, apoptosis, and immune responses. These findings become a basis for further studies to explain the mechanism of PPARγ action in the reproductive system.

Peroxisome proliferator-activated receptor gamma ligands regulate the expression of inflammatory mediators in porcine endometrium during LPS-induced inflammation.

Inflammation in the female reproductive system is one of the most common causes of reproductive dysfunction such as infertility, delay of the reproductive cycle and a reduction in reproductive efficiency. In this study, we aimed to investigate the effect of peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the expression of selected inflammatory mediators: nuclear factor kappa (NF-κB), interleukin (IL)-1ß, IL-6, IL-4, IL-10, leukemia inhibitory factor (LIF) and toll-like receptor 4 (TLR4) in the porcine endometrium treated in vitro with lipopolysaccharide (LPS) on days 10-12 and 18-20 of the estrous cycle. In addition, two experimental protocols were applied to evaluate the role of PPARγ agonists in ongoing and developing inflammation. Endometrial slices were incubated in vitro in the presence of LPS (to induce inflammation) and PPARγ agonists, prostaglandin J2 or pioglitazone (natural or synthetic, respectively). The study showed that PPARγ agonists decreased the expression of pro-inflammatory (NF-κB, TLR4, IL-6) and increased the abundance of anti-inflammatory mediators (IL-10) in the inflamed endometrium of pigs. These findings indicate anti-inflammatory properties of the tested ligands.

Analysis of changes in the proteomic profile of porcine corpus luteum during different stages of the oestrous cycle: effects of PPAR gamma ligands.

CONTEXT: The corpus luteum (CL) is an endocrine gland in the ovary of mature females during the oestrous cycle and pregnancy. There is evidence of a relationship between the secretory function of the CL and PPARs. AIMS: In this study, we investigated the changes in the proteome of the CL in relation to the phase of the oestrous cycle and the impact of PPARγ ligands on the proteomic profile of the CL during the mid- and late-luteal phase of the oestrous cycle. METHODS: The porcine CL explants were incubated in vitro for 6h in the presence of PPARγ ligands (agonist pioglitazone, antagonist T0070907) or without ligands. Global proteomic analysis was performed using the TMT-based LC-MS/MS method. KEY RESULTS: The obtained results showed the disparity in proteomic profile of the untreated CL - different abundance of 23 and 28 proteins for the mid- and late-luteal phase, respectively. Moreover, seven proteins were differentially regulated in the CL tissue treated with PPARγ ligands. In the mid-luteal phase, one protein, CAND1, was downregulated after treatment with T0070907. In the late-luteal phase, the proteins SPTAN1, GOLGB1, TP53BP1, MATR3, RRBP1 and SRRT were upregulated by pioglitazone. CONCLUSIONS: Comparative proteomic analysis revealed that certain proteins constitute a specific proteomic signature for each examined phase. Moreover, the study showed that the effect of PPARγ ligands on the CL proteome was rather limited. IMPLICATIONS: The results provide a broader insight into the processes that may be responsible for the structural luteolysis of the porcine CL, in addition to apoptosis and autophagy.

PPARγ regulates the expression of genes involved in the DNA damage response in an inflamed endometrium.

Inflammation is a biological response of the immune system, which can be triggered by many factors, including pathogens. These factors may induce acute or chronic inflammation in various organs, including the reproductive system, leading to tissue damage or disease. In this study, the RNA-Seq technique was used to determine the in vitro effects of peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the expression of genes and long non-coding RNA, and alternative splicing events (ASEs) in LPS-induced inflammation of the porcine endometrium during the follicular phase of the estrous cycle. Endometrial slices were incubated in the presence of LPS and PPARγ agonists (PGJ2 or pioglitazone) and a PPARγ antagonist (T0070907). We identified 169, 200, 599 and 557 differentially expressed genes after LPS, PGJ2, pioglitazone or T0070907 treatment, respectively. Moreover, changes in differentially expressed long non-coding RNA and differential alternative splicing events were described after the treatments. The study revealed that PPARγ ligands influence the LPS-triggered expression of genes controlling the DNA damage response (GADD45ß, CDK1, CCNA1, CCNG1, ATM). Pioglitazone treatment exerted a considerable effect on the expression of genes regulating the DNA damage response.

PPARγ ligands modulate the immune response mediators in the pig myometrium - An in vitro study.

The current study was conducted with the aim to investigate effects of PPARγ ligands on synthesis of nuclear receptor κB (NF-κB) and selected cytokines (IL-1ß, IFNγ, TNFα, IL-4, IL-10, LIF) in the pig myometrium on days 14-15 of the estrous cycle (late-luteal phase) and days 14-15 of the gestational period (beginning of embryonic implantation). The myometrial slices were incubated in vitro for 6 h in medium containing PPARγ ligands, agonists: 15d-prostaglandin J2 or pioglitazone, and antagonist - T0070907. The mRNA transcript and protein abundances were evaluated in tissues and culture medium. During the estrous cycle, PPARγ ligands did not have an effect on the mRNA transcript abundance of the immune response mediators used for treatments. The IL-10 protein abundance in the tissue was less when there was inclusions of pioglitazone in the medium, while the treatment with T0070907 resulted in a larger abundance of NF-κB, IL-1ß (in the tissue) and IL-4 (in tissue and culture media). During the gestational period, pioglitazone or PGJ2 suppressed mRNA IFNγ and IL-10 transcript and protein abundances (in the tissue and culture media), whereas there was an enhanced NF-κB protein abundance (in the tissue). Treatment with T0070907 had diverse effects (e.g., for NFκB inhibited mRNA transcript abundance or enhanced protein abundance). The observed changes are related mainly in tissues from pregnant animals. Responses to PPARγ antagonist are indicative of the possible involvement of PPARγ-independent factors as well as ligand-independent activation of the receptor, ligand selectivity/functionality or tissue receptivity to the factors evaluated.

A Complex Proteomic Response of the Parasitic Nematode Anisakis simplex s.s. to Escherichia coliLipopolysaccharide.

Helminths are masters at manipulating host's immune response. Especially, parasitic nematodes have evolved strategies that allow them to evade, suppress, or modulate host's immune response to persist and spread in the host's organism. While the immunomodulatory effects of nematodes on their hosts are studied with a great commitment, very little is known about nematodes' own immune system, immune response to their pathogens, and interactions between parasites and bacteria in the host's organism. To illustrate the response of the parasitic nematode Anisakis simplex s.s. during simulated interaction with Escherichia coli, different concentrations of lipopolysaccharide (LPS) were used, and the proteomic analysis with isobaric mass tags for relative and absolute quantification (tandem mass tag-based LC-MS/MS) was performed. In addition, gene expression and biochemical analyses of selected markers of oxidative stress were determined. The results revealed 1148 proteins in a group of which 115 were identified as differentially regulated proteins, for example, peroxiredoxin, thioredoxin, and macrophage migration inhibitory factor. Gene Ontology annotation and Reactome pathway analysis indicated that metabolic pathways related to catalytic activity, oxidation-reduction processes, antioxidant activity, response to stress, and innate immune system were the most common, in which differentially regulated proteins were involved. Further biochemical analyses let us confirm that the LPS induced the oxidative stress response, which plays a key role in the innate immunity of parasitic nematodes. Our findings, to our knowledge, indicate for the first time, the complexity of the interaction of parasitic nematode, A. simplex s.s. with bacterial LPS, which mimics the coexistence of helminth and gut bacteria in the host. The simulation of this crosstalk led us to conclude that the obtained results could be hugely valuable in the integrated systems biology approach to describe a relationship between parasite, host, and its commensal bacteria.

Transcriptome analysis of porcine endometrium after LPS-induced inflammation: effects of the PPAR-gamma ligands in vitro†.

Female fertility depends greatly on the capacity of the uterus to recognize and eliminate microbial infections, a major reason of inflammation in the endometrium in many species. This study aimed to determine the in vitro effect of peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the transcriptome genes expression and alternative splicing in the porcine endometrium in the mid-luteal phase of the estrous cycle during LPS-stimulated inflammation using RNA-seq technology. The endometrial slices were incubated in vitro in the presence of LPS and PPARγ agonists-PGJ2 or pioglitazone and antagonist-T0070907. We identified 222, 3, 4, and 62 differentially expressed genes after LPS, PGJ2, pioglitazone, or T0070907 treatment, respectively. In addition, we detected differentially alternative spliced events: after treatment with LPS-78, PGJ2-60, pioglitazone-52, or T0070907-134. These results should become a basis for further studies explaining the mechanism of PPARγ action in the reproductive system in pigs.

Peroxisome proliferator-activated receptor gamma ligands affect NF-kB and cytokine synthesis in the porcine endometrium-An in vitro study.

PROBLEM: Cytokines, mediators of the immune response, are involved in the regulation of female reproductive processes during the estrous cycle and pregnancy. The present study aimed to investigate the effect of selected peroxisome proliferator-activated receptor gamma (PPARγ) ligands on the expression of nuclear factor kappa B (NF-κB) and selected cytokines, such as interleukin (IL)-1ß, -4, -6, -8, -10, and the leukemia inhibitory factor, in the porcine endometrium on days 10-12 and 14-16 of the estrous cycle (mid- and late luteal phase, respectively) or pregnancy (maternal recognition of pregnancy and beginning of implantation, respectively). METHOD OF STUDY: Endometrial slices were incubated in vitro in the presence of PPARγ agonists, 15-deoxy-Δ12, 14-prostaglandin J2 or rosiglitazone, and PPARγ antagonist T0070907. mRNA and protein levels in tissues were determined by real-time PCR and Western blot. RESULTS: On days 10-12 of the estrous cycle and days 14-16 of pregnancy, PPARγ ligands enhanced the expression of NF-κB, mRNA cytokines, and/or proteins. During the late luteal phase of the estrous cycle (days 14-16) and maternal recognition of pregnancy (days 10-12), PPARγ ligands inhibited the expression of NF-κB, and they differentially affected the expression of mRNA and proteins of cytokines. CONCLUSION: Our results indicate that PPARγ is engaged in the endometrial synthesis of NF-κB and selected cytokines in pigs. The influence of PPARγ ligands on the tested components of the immune system varied subject to the physiological status of females, and it could be associated with differences in endometrial receptivity.