Inhibitory Effect of Bovine Adipose-Derived Mesenchymal Stem Cells on Lipopolysaccharide Induced Inflammation of Endometrial Epithelial Cells in Dairy Cows

The mammosphere-derived epithelial cell secretome modulates neutrophil functions in the bovine model

Background

Innovative therapies against bacterial infections are needed. One approach is to focus on host-directed immunotherapy (HDT), with treatments that exploit natural processes of the host immune system. The goals of this type of therapy are to stimulate protective immunity while minimizing inflammation-induced tissue damage. We use non-traditional large animal models to explore the potential of the mammosphere-derived epithelial cell (MDEC) secretome, consisting of all bioactive factors released by the cells, to modulate host immune functions. MDEC cultures are enriched for mammary stem and progenitor cells and can be generated from virtually any mammal. We previously demonstrated that the bovine MDEC secretome, collected and delivered as conditioned medium (CM), inhibits the growth of bacteria in vitro and stimulates functions related to tissue repair in cultured endothelial and epithelial cells.

Methods

The immunomodulatory effects of the bovine MDEC secretome on bovine neutrophils, an innate immune cell type critical for resolving bacterial infections, were determined in vitro using functional assays. The effects of MDEC CM on neutrophil molecular pathways were explored by evaluating the production of specific cytokines by neutrophils and examining global gene expression patterns in MDEC CM-treated neutrophils. Enzyme linked immunosorbent assays were used to determine the concentrations of select proteins in MDEC CM and siRNAs were used to reduce the expression of specific MDEC-secreted proteins, allowing for the identification of bioactive factors modulating neutrophil functions.

Results

Neutrophils exposed to MDEC secretome exhibited increased chemotaxis and phagocytosis and decreased intracellular reactive oxygen species and extracellular trap formation, when compared to neutrophils exposed to control medium. C-X-C motif chemokine 6, superoxide dismutase, peroxiredoxin-2, and catalase, each present in the bovine MDEC secretome, were found to modulate neutrophil functions.

Conclusion

The MDEC secretome administered to treat bacterial infections may increase neutrophil recruitment to the site of infection, stimulate pathogen phagocytosis by neutrophils, and reduce neutrophil-produced ROS accumulation. As a result, pathogen clearance might be improved and local inflammation and tissue damage reduced.

The Effect of Selenium on Endometrial Repair in Goats with Endometritis at High Cortisol Levels

Endometritis is a common postpartum disease of female animals that causes significant losses to the goat industry. High levels of cortisol induced by various stresses after delivery severely inhibit innate immunity and tissue repair. The repair ability of the endometrium is closely related to the reproductive performance of goats. Selenium (Se) is an essential trace element in animals that has powerful antioxidant and immunity-enhancing functions. In this study, we established a goat model of endometritis at high cortisol (Hydrocortisone) levels to investigate the effect of Se (supplement additive) on endometrial repair. The results showed that the clinical symptoms, %PMN in uterine secretions, morphological endometrial damage, and the gene expression of BAX were reduced in the goats with Se supplementation compared with those in the model group. Se increased the gene expression of BCL2, VEGFA, TGFB1, and PCNA and activated the PI3K/AKT and Wnt/β-catenin signaling pathways in goats with Se supplementation. In conclusion, Se reduced the inflammatory response, increased the proliferation, and decreased the apoptosis of endometrial cells to promote endometrial tissue repair in goats with endometritis at high cortisol levels. It probably achieved this effect of promoting repair by activating the Wnt/β-catenin and PI3K/AKT pathways and affecting the gene expression of VEGFA, TGFB1, PCNA, BCL2, and BAX.

Development potential of selenium in the prevention and treatment of bovine endometritis

Endometritis is a common postpartum disease in cows. It delays uterine involution and impairs normal physiological function. This can result in long-term or even lifelong infertility and cause significant losses to the dairy farming industry. Traditional treatments like antibiotics possess certain shortcomings, such as antibiotic residues, the abuse of antibiotics, and increased antimicrobial resistance of pathogens. Alternative treatment strategies are needed to minimize the utilization of antibiotics in dairy production. As an essential trace element in animals, selenium (Se) plays a vital role in regulating immune function, the inflammatory response, and oxidative stress, affecting the speed and completeness of tissue repair. This paper reviewed previous studies to analyse the potential of Se in the prevention and treatment of bovine endometritis, aiming to provide a new direction to increase production capacity in the future.

The effect of selenium on the proliferation of bovine endometrial epithelial cells in a lipopolysaccharide-induced damage model

BACKGROUND

Endometritis is a common bovine postpartum disease. Rapid endometrial repair is beneficial for forming natural defense barriers and lets cows enter the next breeding cycle as soon as possible. Selenium (Se) is an essential trace element closely related to growth and development in animals. This study aims to observe the effect of Se on the proliferation of bovine endometrial epithelial cells (BEECs) induced by lipopolysaccharide (LPS) and to elucidate the possible underlying mechanism.

RESULTS

In this study, we developed a BEECs damage model using LPS. Flow cytometry, cell scratch test and EdU proliferation assay were used to evaluate the cell cycle, migration and proliferation. The mRNA transcriptions of growth factors were detected by quantitative reverse transcription-polymerase chain reaction. The activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and Wnt/β-catenin pathways were detected by Western blotting and immunofluorescence. The results showed that the cell viability and BCL-2/BAX protein ratio were significantly decreased, and the cell apoptosis rate was significantly increased in the LPS group. Compared with the LPS group, Se promoted cell cycle progression, increased cell migration and proliferation, and significantly increased the gene expressions of TGFB1, TGFB3 and VEGFA. Se decreased the BCL-2/BAX protein ratio, promoted β-catenin translocation from the cytoplasm to the nucleus and activated the Wnt/β-catenin and PI3K/AKT signaling pathways inhibited by LPS.

CONCLUSIONS

In conclusion, Se can attenuate LPS-induced damage to BEECs and promote cell proliferation and migration in vitro by enhancing growth factors gene expression and activating the PI3K/AKT and Wnt/β-catenin signaling pathways.

Mesenchymal stromal cells modulate infection and inflammation in the uterus and mammary gland

The use of mesenchymal stromal cells (MSCs) is emerging as an efficacious and safe treatment for many infectious and non-infectious inflammatory diseases in human and veterinary medicine. Such use could be done to treat mastitis and metritis, which are the most common disease conditions affecting dairy cows leading to considerable economic losses and reduced animal welfare. Currently, both disease conditions are commonly treated using local and systemic administration of antibiotics. However, this strategy has many disadvantages including low cure rates and the public health hazards. Looking for alternative approaches, we investigated the properties of MSCs using in-vitro mammary and endometrial cell systems and in-vivo mastitis and metritis murine model systems. In-vitro, co-culture of mammary and uterus epithelial cells constructed with NF-kB reporter system, the master regulator of inflammation, demonstrated their anti-inflammatory effects in response to.LPS. In vivo, we challenge animals with field strains of mammary and utero pathogenic Escherichia coli and evaluated the effects of local and systemic application of MSC in the animal models. Disease outcome was evaluated using histological analysis, bacterial counts and gene expression of inflammatory markers. We show that MSC treatment reduced bacterial load in metritis and significantly modulated the inflammatory response of the uterus and mammary gland to bacterial infection. Most notably are the immune modulatory effects of remotely engrafted intravenous MSCs, which open new avenues to the development of MSC-based cell-free therapies.

Exosomes From Adipose-Derived Stem Cells Suppress the Progression of Chronic Endometritis

Chronic endometritis (CE) is closely linked to the reproductive failure. Exosome (Exo)-based therapy is proposed as an encouraging strategy in inflammation-related disorders; however, little work has been devoted to its usage in CE therapy. An in vitro CE was established by administration of lipopolysaccharide (LPS) in human endometrial stromal cells (HESCs). The cell proliferation, cell apoptosis, and inflammatory cytokine assays were performed in vitro, and the efficacy of Exos derived from adipose tissue-derived stem cells (ADSCs) was evaluated in a mouse model of CE. We found that Exos isolated from ADSCs could be taken up by HESCs. Exos elevated the proliferation and inhibited apoptosis in LPS-treated HESCs. Administration of Exos to HESCs suppressed the content of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). Moreover, Exos exposure repressed the inflammation stimulated by LPS in vivo. Mechanistically, we demonstrated that Exos exerted their ant-inflammatory effect via miR-21/TLR4/NF-kB signaling pathway in endometrial cells. Our findings suggest that ADSC-Exo-based therapy might serve as an attractive strategy for the treatment of CE.

An Update on Applications of Cattle Mesenchymal Stromal Cells

Simple Summary

Among livestock species, cattle are crucially important for the meat and milk production industry. Cows can be affected by different pathologies, such as mastitis, endometritis and lameness, which can negatively affect either food production or reproductive efficiency. The use of mesenchymal stromal cells (MSCs) is a valuable tool both in the treatment of various medical conditions and in the application of reproductive biotechnologies. This review provides an update on state-of-the-art applications of bovine MSCs to clinical treatments and reproductive biotechnologies.

Abstract

Attention on mesenchymal stromal cells (MSCs) research has increased in the last decade mainly due to the promising results about their plasticity, self-renewal, differentiation potential, immune modulatory and anti-inflammatory properties that have made stem cell therapy more clinically attractive. Furthermore, MSCs can be easily isolated and expanded to be used for autologous or allogenic therapy following the administration of either freshly isolated or previously cryopreserved cells. The scientific literature on the use of stromal cells in the treatment of several animal health conditions is currently available. Although MSCs are not as widely used for clinical treatments in cows as for companion and sport animals, they have the potential to be employed to improve productivity in the cattle industry. This review provides an update on state-of-the-art applications of bovine MSCs to clinical treatments and reproductive biotechnologies.

Two New Xanthones from the Twigs of Calophyllum membranaceum and Their Anti-Inflammatory Activities in HESC Cells

Two new xanthones, calmemxanthone A (1) and calmemxanthone B (2), along with eleven known compounds were isolated from the dried twigs of Calophyllum membranaceum Gardn. et Champ. The structures of compounds 1 and 2 were established by analysis of spectra and mass spectrometry data. The absolute configuration of compound 1 was confirmed by electronic circular dichroism (ECD) spectral analysis. The anti-inflammation action of these compounds were evaluated on lipopolysaccharide (LPS)-induced inflammatory damage to human endometrial stromal cells (HESCs), and the structure-activities of 1-13 were also discussed. Compound 10 presented the anti-inflammation action with an IC₅₀ value of 20.3 μM, that might be relevant to the regulation of NF-κB signaling pathway via the suppression of TRIF, IKKα, and IκBα.