Therapeutic administration of Luteolin protects against Escherichia coli-derived Lipopolysaccharide-triggered inflammatory response and oxidative injury.

Endometritis reduces reproductive effectiveness and leads to significant financial losses in the dairy sector. Luteolin is a natural phyto-flavonoid compound with many biological activities. However, the therapeutic effect of Luteolin against lipopolysaccharides (LPS)-induced endometritis has not yet been explored. A total of eighty female Kunming mice were randomly assigned into four treatment groups (n = 20). Following a successful initiation of the endometritis model by LPS, Luteolin was intraperitoneally administered three times, at six-hour intervals between each injection in the Luteolin groups. The histopathological findings revealed that Luteolin significantly alleviated uterine injury induced by LPS. Moreover, Luteolin suppressed the synthesis of pro-inflammatory mediators [interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α] while promoting the synthesis of an anti-inflammatory mediator (IL-10) altered by LPS. Furthermore, Luteolin significantly mitigated the LPS-induced oxidative stress by scavenging malondialdehyde (MDA) and reactive oxygen species (ROS), accumulation and boosting the capacity of antioxidant enzyme activities such as superoxide dismutase 1 (SOD1), catalase (CAT), and glutathione peroxidase 1 (Gpx1) in the uterine tissue of mice. Additionally, injection of Luteolin markedly increased the expression of Toll-like receptors (TLR) 4 both at mRNA and protein levels under LPS stimulation. Western blotting and ELISA findings demonstrated that Luteolin suppressed the activation of the NF-κB pathway in response to LPS exposure in the uterine tissue of mice. Notably, Luteolin enhanced the anti-oxidant defense system by activating the Nrf2 signaling pathway under LPS exposure in the uterine tissue of mice. Conclusively, our findings demonstrated that Luteolin effectively alleviated LPS-induced endometritis via modulation of TLR4-associated Nrf2 and NF-κB signaling pathways.

Up-regulation of inflammatory, oxidative stress, and apoptotic mediators via inflammatory, oxidative stress, and apoptosis-associated pathways in bovine endometritis.

Endometritis is the inflammation of the endothelial lining of the uterine lumen and is multifactorial in etiology. Escherichia (E.) coli is a Gram-negative bacteria, generally considered as a primary causative agent for bovine endometritis. Bovine endometritis is characterized by the activation of Toll-like receptors (TLRs) by E. coli, which in turn triggers inflammation, oxidative stress, and apoptosis. The objective of this study was to investigate the gene expression of inflammatory, oxidative stress, and apoptotic markers related to endometritis in the uteri of cows. Twenty uterine tissues were collected from the abattoir. Histologically, congestion, edema, hyperemia, and hemorrhagic lesions with massive infiltration of neutrophil and cell necrosis were detected markedly (P < 0.05) in infected uterine samples. Additionally, we identify E. coli using the ybbW gene (177 base pairs; E. coli-specific gene) from infected uterine samples. Moreover, qPCR and western blot results indicated that TLR2, TLR4, proinflammatory mediators, and apoptosis-mediated genes upregulated except Bcl-2, which is antiapoptotic, and there were downregulations of oxidative stress-related genes in the infected uterine tissue. The results of our study suggested that different gene expression regimes related to the immune system reflex were activated in infected uteri. This research gives a novel understanding of active immunological response in bovine endometritis.

Ginsenoside Rb1 Mitigates Escherichia coli Lipopolysaccharide-Induced Endometritis through TLR4-Mediated NF-κB Pathway.

Endometritis is the inflammatory response of the endometrial lining of the uterus and is associated with low conception rates, early embryonic mortality, and prolonged inter-calving intervals, and thus poses huge economic losses to the dairy industry worldwide. Ginsenoside Rb1 (GnRb1) is a natural compound obtained from the roots of Panax ginseng, having several pharmacological and biological properties. However, the anti-inflammatory properties of GnRb1 in lipopolysaccharide (LPS)-challenged endometritis through the TLR4-mediated NF-κB signaling pathway has not yet been researched. This study was planned to evaluate the mechanisms of how GnRb1 rescues LPS-induced endometritis. In the present research, histopathological findings revealed that GnRb1 ameliorated LPS-triggered uterine injury. The ELISA and RT-qPCR assay findings indicated that GnRb1 suppressed the expression level of pro-inflammatory molecules (TNF-α, IL-1ß and IL-6) and boosted the level of anti-inflammatory (IL-10) cytokine. Furthermore, the molecular study suggested that GnRb1 attenuated TLR4-mediated NF-κB signaling. The results demonstrated the therapeutic efficacy of GnRb1 in the mouse model of LPS-triggered endometritis via the inhibition of the TLR4-associated NF-κB pathway. Taken together, this study provides a baseline for the protective effect of GnRb1 to treat endometritis in both humans and animals.

Ginsenoside Rb1 protects from Staphylococcus aureus-induced oxidative damage and apoptosis through endoplasmic reticulum-stress and death receptor-mediated pathways.

Acute lung injury (ALI) is acute uncontrolled inflammation of lung tissue that leads to high fatality both in human and animals. Staphylococcus aureus (S. aureus) could be an opportunistic, versatile bacterial etiology of ALI. Ginsenoside Rb1 (Rb1) is extracted from the Panax ginseng, which displays a wide range of biological and pharmacological effects. However, protective effects of Rb1 in S. aureus-induced ALI though endoplasmic reticulum (ER) stress and death receptor-mediated pathways have not yet been reported. Therefore, present study was planned with the aims to investigate the antioxidant and anti-apoptotic properties of Rb1 through regulation of ER stress as well as death receptor-mediated pathways in ALI induced by S. aureus in mice. In this study, four groups of healthy Kunming mice (n = 48) were used. The S. aureus (80 µl; 1 ×107 CFU/10 µl) was administered intranasally to establish mice model of ALI. After 24 h of onset of S. aureus-induced ALI, the mice were injected thrice with Rb1 (40 mg/kg) intraperitoneally six hours apart. Histopathology, enzyme linked immunosorbent assay (ELISA), real time quantitative polymerase chain reaction (RT-qPCR), Immunohistochemistry and western blotting assay were employed in the current study. Our results suggested that Rb1 administration save lungs from pulmonary injury by reducing wet to dry (W/D) ratio, protein levels, total cells, neutrophilic count, reactive oxygen species (ROS), myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx)1 depletion. Meanwhile, Rb1 therapy ameliorated histopathology alteration of lung tissue and pro-inflammatory cytokines secretion. The gene expression of ER stress marker (PERK, AFT-6, IRE1 and CHOP) were upregulated markedly (P < .05) in S. aureus-instilled groups, which was reduced by Rb1 administration that is reveled from the result findings of the RT-qPCR and immunoblot assay. The results of immunohistochemistry for CHOP indicated the increased expression in S. aureus groups which in turn ameliorated by Rb1 treatment. The mRNA expression demonstrated that death receptor-associated genes (FasL, Fas, FADD and caspase-8) showed up-regulation in S. aureus group. The similar findings were observed for the protein expression of caspase-8, FADD and Fas. Rb1 treatment markedly (P < .05) reversed protein and mRNA expression levels of these death receptor-associated genes when compared to the S. aureus group. Taken together, Rb1 attenuated S. aureus-induced oxidative damage via the ER stress-mediated pathway and apoptosis through death receptor-mediated pathway. Conclusively, our findings provide an insight into preventive mechanism of Rb1 in ALI caused by S. aureus and hence proven a scientific baseline for the therapeutic application of Rb1.

Upregulated-gene expression of pro-inflammatory cytokines, oxidative stress and apoptotic markers through inflammatory, oxidative and apoptosis mediated signaling pathways in Bovine Pneumonia.

Pneumonia is the acute inflammation of lung tissue and is multi-factorial in etiology. Staphylococcus aureus (S. aureus) is a harmful pathogen present as a normal flora of skin and nares of dairy cattle. In bovine pneumonia, S. aureus triggers to activates Toll-Like Receptors (TLRs), that further elicits the activation of the inflammation via NF-κB pathway, oxidative stress and apoptotic pathways. In the current study, pathogen-associated gene expression of the pro-inflammatory cytokines, oxidative stress and apoptotic markers in the lung tissue of cattle was explored in bovine pneumonia. Fifty lung samples collected from abattoir located in Wuhan city, Hubei, China. Histopathologically, thickening of alveolar wall, accumulation of inflammatory cells and neutrophils in perivascular space, hyperemia, hemorrhages and edema were observed in infected lungs as compared to non-infected lung samples. Furthermore, molecular identification and characterization were carried by amplification of S. aureus-specific nuc gene (270 base pairs) from the infected and non-infected lung samples to identify the S. aureus. Moreover, qPCR results displayed that relative mRNA levels of TLR2, TLR4, pro-inflammatory gene (IL-1ß, IL-6 and TNF-α) and apoptosis-associated genes (Bax, caspase-3 and caspase-9) were up-regulated except Bcl-2, which is antiapoptotic in nature, and oxidative stress related genes (Nrf2, NQO1, HO-1 and GCLC) which was down-regulated in infected pulmonary group. The relative protein expression of NF-κB, mitochondria-mediated apoptosis gene was up-regulated while Bcl-2 and Nrf2 pathway genes were downregulated in infected cattle lungs. Our findings revealed that genes expression levels of inflammatory mediators, oxidative stress and apoptosis were associated with host immunogenic regulatory mechanisms in the lung tissue during infection. Conclusively, the present study provides insights of active immune response via TLRs-mediated inflammatory, oxidative damage, and apoptotic paradox.