Search Results (59)

Recurrent implantation failure (RIF) remains a challenging clinical problem. Growth hormone (GH) co-treatment has been explored as an adjunct in poor responders and RIF patients, with inconsistent evidence of benefit. This prospective cohort study assessed the impact of GH supplementation in 91 RIF patients undergoing in vitro fertilization, stratified by FSHR (follicular stimulating hormone receptor) genotype Asn680Ser with or without GH supplementation. Patients were stratified by FSHR genotype into homozygous Ser/Ser versus Ser/Asn or Asn/Asn groups. Overall, GH co-treatment conferred modest benefits in the unselected RIF cohort, limited to a higher cumulative live birth rate compared to controls and elevated leukemia inhibitory factor (LIF) levels (p < 0.05 both). When stratified by FSHR genotype, the Ser/Ser subgroup exhibited markedly better outcomes with GH. These patients showed a higher (0.5 vs. 0.33, p = 0.003), produced more embryos (2.88 vs. 1.53, p = 0.02), and had a markedly improved cumulative live birth rate—50% with GH versus 13% without—highlighting a clinically meaningful benefit of GH in the Ser/Ser subgroup. No significant benefit was observed in Asn allele carriers. These findings suggest that FSHR genotyping may help optimize treatment selection in RIF patients by identifying those most likely to benefit from GH supplementation. Full article

Endometriosis is a complex gynecological disorder characterized by the presence of endometrial-like tissue outside the uterus, leading to chronic pain and infertility. Immunohistochemistry (IHC) serves as a vital technique for elucidating the molecular and cellular differences between ectopic endometriotic tissues and eutopic endometrium. IHC reveals significant variations in the expression of inflammatory markers, adhesion molecules, and cell cycle regulators. This literature review compiles findings from various studies that assess the role of key proteins, such as leukemia inhibitory factor (LIF), cyclooxygenase-2 (COX-2), and b-cell lymphoma 2 (BCL-2), across different menstrual phases and lesion types. Notably, elevated LIF levels and increased mast cell activity in ectopic tissues underscore the inflammatory landscape of endometriosis. Additionally, altered expression of adhesion molecules like integrins and cluster of differentiation 44 (CD44) suggests modified cellular interactions, while apoptotic markers reveal a survival advantage for ectopic cells. These insights enhance our understanding of endometriosis pathophysiology. Full article

Oxidative stress due to increased reactive oxygen species (ROS) formation and/or inflammation is considered to play an important role in ischemic stroke injury. Leukemia inhibitory factor (LIF) has been shown to protect both oligodendrocytes and neurons from ischemia by upregulating endogenous anti-oxidants, though the effect of ischemia and the protective role of LIF treatment in mitochondrial function have not been studied. The goal of this study was to determine whether LIF protects ischemia-induced altered mitochondrial bioenergetics in reproductively senescent aged rats of both sexes (≥18 months old), approximately equivalent to the average age of human stroke patients. Animals were euthanized at 3 days after permanent middle cerebral artery occlusion (MCAO) surgery. We found that MCAO surgery significantly reduced mitochondrial oxidative phosphorylation in both the ipsilateral striatum and prefrontal cortex in male aged rats compared to their respective contralateral regions of the brain. MCAO injury showed mitochondrial bioenergetic dysfunction only in the striatum in female rats; however, the prefrontal cortex remained unaffected to the injury. LIF-treated rats significantly prevented mitochondrial dysfunction in the striatum in male rats compared to their vehicle-treated counterparts. Collectively, MCAO-induced mitochondrial dysfunction and LIF’s potential as a therapeutic biomolecule exhibited sex- and tissue-specific effects, varying between the striatum and prefrontal cortex in male and female rats. Full article

In eutherian mammals, embryo implantation is a critical process for a successful pregnancy. In mice, the activation of the leukemia inhibitory factor (LIF) receptor–STAT3 signaling axis induces embryo adhesion and decidualization. The LIF receptor is believed to function as a heterodimer composed of LIFR (encoded by Lifr) and GP130 (encoded by Il6st); however, their distinct expression patterns in the uterine epithelium immediately prior to implantation suggest divergent functional roles. In this study, we generated uterine epithelium-specific Lifr knockout (Lifr eKO) mice and conducted a comprehensive gene expression analysis of the endometrium before implantation. We compared these results with those from uterine epithelium-specific Gp130 knockout (Gp130 eKO) mice. Similarly to Gp130 eKO mice, Lifr eKO mice were completely infertile. We identified 299 genes with expression changes greater than twofold following gene deletion; among these, 31 genes were downregulated and 57 genes were upregulated in both eKO models. Many of the downregulated genes were previously implicated in uterine function. Hub gene analysis identified Erbb2 and c-Fos as key regulators in both models. Further experiments using an ERBB2 inhibitor suggested that LIFR–ERBB2-mediated signaling plays a crucial role in embryo implantation. Full article

This work explored whether supplementing recombinant human interleukin-6 (IL6), interleukin-11 (IL11), or leukemia inhibitory factor (LIF) improves IVP bovine embryo development, morphology, and cryosurvivability. Embryos were treated from day 5 to 8 post-fertilization with either the carrier only (control) or 100 ng/mL of IL6, IL11, or LIF. Blastocyst formation and stage were determined on day 7 and 8. A subset of day 8 blastocysts was processed for immunofluorescence to count trophectoderm (TE) and inner cell mass (ICM) cell numbers and another subset was slow frozen and stored in liquid nitrogen until thawing. No differences in the blastocyst rate or blastocyst stage of development were detected. Increases in ICM cell numbers were observed for IL6 and LIF but not the IL11 treatment. None of the cytokine treatments applied before freezing affected post-thaw survival, TE or ICM cell number, or cell death 24 h after thawing. In conclusion, supplementing IL6 and LIF improves ICM cell numbers in non-frozen blastocysts, but there was no evidence that any of these cytokine treatments contain cryoprotective properties in bovine embryos. Full article

Background: Inflammatory breast cancer (IBC) is a rare subtype of breast cancer accounting for 7% of breast cancer-related fatalities. There is an urgent need to develop new targeted treatments for IBC. The progression of IBC has been associated with alterations in growth factor and cytokine signaling; however, the function of the LIF (leukemia inhibitory factor)/LIFR (leukemia inhibitory factor receptor) cytokine pathway in the progression of IBC remains unknown. This study evaluated the role of LIFR signaling and tested the efficacy of the LIFR inhibitor EC359 in treating IBC. Methods: The utility of using LIFR inhibition as a treatment strategy in IBC was tested using cell survival, apoptosis, colony formation, invasion, and pre-clinical KPL4 xenografts. Western blotting, siRNA, RT-qPCR, and lipid peroxidation assays were used to establish the mechanism of EC359 therapy. Results: The reduction in LIFR levels using siRNA markedly decreased growth in colony formation assays and reduced the invasion of IBC cells. Pharmacological inhibition of LIFR with EC359 effectively reduced cell survival and the clonogenic capacity of IBC cells. RT-qPCR assays revealed that EC359 markedly decreased the expression of the LIFR target genes. Western blot analyses confirmed that EC359 treatment suppressed downstream LIF/LIFR signaling pathways and promoted apoptosis. Treatment of cells with the ferroptosis inhibitor Fer-1 negated the capacity of EC359 to induce apoptosis. Mechanistic investigations demonstrated that EC359 predominantly triggered ferroptosis by inhibiting the glutathione antioxidant defense system through the downregulation of Glutathione peroxidase 4 (GPX4) levels. EC359 (5 mg/kg/day) was effective in reducing the growth of the IBC KPL4 xenograft tumors. Conclusion: These findings demonstrates that LIFR inhibition promote ferroptosis-mediated cell death in IBC and that EC359 represent novel therapeutic for IBC treatment. Full article

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC), expecting to be the second leading cause of cancer deaths by 2030, resists immune checkpoint therapies due to its immunosuppressive tumor microenvironment (TME). Leukemia inhibitory factor (LIF) is a key target in PDAC, promoting stemness, epithelial–mesenchymal transition (EMT), and therapy resistance. Phase 1 clinical trials showed anti-LIF therapy is safe but with limited efficacy, suggesting better outcomes when combined with chemotherapy, radiotherapy, or immunotherapy. Methods: We assessed the combination of chemotherapy (gemcitabine/nab-paclitaxel) and dual blockade of LIF and PD-L1 on tumor growth and survival in orthotopic and spontaneous PDAC models. Flow cytometry and scRNA-seq were utilized to monitor the antitumor immune response. The role of key immune cells was further confirmed by depleting these immune cells, including CD4, CD8, or inflammatory monocytes. Results: Sequential treatment with chemotherapy (gemcitabine/nab-paclitaxel) and dual blockade of LIF and PD-L1 significantly improved antitumor efficacy compared to monotherapy or dual combinations of these therapies. This chemo/anti-LIF/anti-PD-L1 approach reduced EMT in tumor cells and enhanced the antitumor immune response, primarily through CD8 T cells, as depleting CD8 cells largely abrogated the effect of treatment. This combination therapy also shifted macrophages and dendritic cells towards an antitumor phenotype. Conclusions: The combination of chemotherapy, anti-LIF, and anti-PD-L1 not only targeted tumor cells but also augmented the anti-tumor immune response. These findings strongly support advancing chemo/anti-LIF/anti-PD-L1 combination therapy to clinical trials in PDAC. Full article

Communications between different cell types within a tissue are often critical for the proper functioning of an organ. In the central nervous system, interactions among neurons and glial cells are known to modulate neurotransmission, energy metabolism, extracellular ion homeostasis, and neuroprotection. Here we showed that bradykinin, a proinflammatory neuropeptide, can be detected by astrocytes, resulting in the secretion of cytokines that act on neurons. In astrocytic cell lines and primary astrocytes, bradykinin and several other ligands acting on G_q-coupled receptors stimulated Ca²⁺ mobilization, which subsequently led to the release of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6). The bradykinin B₂ receptor antagonist, HOE-140, effectively blocked the ability of bradykinin to mobilize Ca²⁺ and stimulate mitogen-activated protein kinases (MAPKs) in astrocytes. Interestingly, incubation of neuronal cell lines and primary cortical neurons with conditioned media from bradykinin-treated astrocytes resulted in the activation of STAT3, a key component downstream of LIF and IL-6 receptors. LIF was apparently the major active factor in the conditioned media as the STAT3 response was almost completely neutralized by an anti-LIF antiserum. The presence of kininogen and kallikrein transcripts in neuronal cells but not in astrocytic cells indicates that neurons can produce bradykinin. Correspondingly, conditioned media from neuronal cells stimulated MAPKs in astrocytes in a HOE-140-sensitive manner. These studies demonstrate that paracrine signaling between neurons and astrocytes may involve ligands of G_q-coupled receptors and cytokines such as LIF. Full article

Microglia, the brain immune cells, support neurons by producing several established neurotrophic molecules including glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Modern analytical techniques have identified numerous phenotypic states of microglia, each associated with the secretion of a diverse set of substances, which likely include not only canonical neurotrophic factors but also other less-studied molecules that can interact with neurons and provide trophic support. In this review, we consider the following eight such candidate cytokines: oncostatin M (OSM), leukemia inhibitory factor (LIF), activin A, colony-stimulating factor (CSF)-1, interleukin (IL)-34, growth/differentiation factor (GDF)-15, fibroblast growth factor (FGF)-2, and insulin-like growth factor (IGF)-2. The available literature provides sufficient evidence demonstrating murine cells produce these cytokines and that they exhibit neurotrophic activity in at least one neuronal model. Several distinct types of neurotrophic activity are identified that only partially overlap among the cytokines considered, reflecting either their distinct intrinsic properties or lack of comprehensive studies covering the full spectrum of neurotrophic effects. The scarcity of human-specific studies is another significant knowledge gap revealed by this review. Further studies on these potential microglia-derived neurotrophic factors are warranted since they may be used as targeted treatments for diverse neurological disorders. Full article

American women with obesity have an increased incidence of triple-negative breast cancer (TNBC). The impact of obesity conditions on the tumor microenvironment is suspected to accelerate TNBC progression; however, the specific mechanism(s) remains elusive. This study explores the hypothesis that obesity upregulates leukemia inhibitory factor receptor (LIFR) oncogenic signaling in TNBC and assesses the efficacy of LIFR inhibition with EC359 in blocking TNBC progression. TNBC cell lines were co-cultured with human primary adipocytes, or adipocyte-conditioned medium, and treated with EC359. The effects of adiposity were measured using cell viability, colony formation, and invasion assays. Mechanistic studies utilized RNA-Seq, Western blotting, RT-qPCR, and reporter gene assays. The therapeutic potential of EC359 was tested using xenograft and patient-derived organoid (PDO) models. The results showed that adipose conditions increased TNBC cell proliferation and invasion, and these effects correlated with enhanced LIFR signaling. Accordingly, EC359 treatment reduced cell viability, colony formation, and invasion under adipose conditions and blocked adipose-mediated organoid growth and TNBC xenograft tumor growth. RNA-Seq analysis identified critical pathways modulated by LIF/LIFR signaling in diet-induced obesity mouse models. These findings suggest that adiposity contributes to TNBC progression via the activation of the LIF/LIFR pathway, and LIFR inhibition with EC359 represents a promising therapeutic approach for obesity-associated TNBC. Full article

Melatonin plays a critical role in regulating embryo attachment in ruminants. While numerous studies have investigated its effects on early embryo development in vitro, the precise mechanisms by which melatonin influences the receptivity of endometrial epithelial cells in dairy cows remain unclear. The prerequisite for embryo implantation is the specific physiological condition of the endometrium that allows the embryo to implant, also known as endometrial receptivity. In addition to this, endometrial cells undergo processes such as proliferation, differentiation, and renewal, which makes the embryo more easily implanted. In this study, bovine endometrial epithelial cells were cultured and treated with melatonin, Silent Information Regulator 1 (SIRT1) inhibitor (EX527), and protein kinase B (AKT) phosphorylation inhibitor (periposine). RT-qPCR, Western blot, and immunofluorescence analysis were performed to investigate the effects of melatonin on the expression of target gene (SIRT1); cell proliferative genes, phosphatidylinositol-4,5-bisphosphate 3-Kinase (PI3K), AKT, cyclinD1, cyclinE1; and receptive genes (Leukemia Inhibitory Factor (LIF), Vascular Endothelial Growth Factor (VEGF), Homeobox Structure Gene 10 (HOXA10)). Additionally, microRNA (miRNA) mimics and inhibitors were used to transfect the cells to study the regulatory relationship between miRNA and receptive genes. Results indicated that melatonin activates the PI3K/AKT signaling pathway, upregulates cyclinD1 and cyclinE1, and promotes the proliferation of bovine endometrial epithelial cells. Melatonin also upregulated the expression of VEGF and HOXA10 and downregulated the expression of bta-miR-497 and bta-miR-27a-3p through SIRT1/PI3K/AKT signaling pathway. Further, bta-miR-497 and bta-miR-27a-3p were found to negatively regulate VEGF and HOXA10, respectively. Therefore, melatonin regulates the expression of VEGF and HOXA10 through the SIRT1/PI3K/AKT pathway and promotes the establishment of receptivity in bovine endometrial epithelial cells. Full article

Background/Objectives: While it is known that adenomyosis is associated with poor reproductive outcomes, the underlying mechanisms are unclear, and to date, there is no standard treatment protocol for these patients. Endometrium from adenomyosis patients is characterized by several abnormalities, potentially resulting in impaired receptivity and subsequent implantation failure. Methods: Endometrial biopsies were collected from 26 women with adenomyosis and 26 control subjects. Immunohistochemistry was performed to evaluate the expression of markers of endometrial receptivity, namely the progesterone receptor (PR), glycodelin, leukemia inhibitory factor (LIF), homeobox A10 (HOXA10), integrin beta chain beta 3 (integrin β3) and osteopontin. Scanning electron microscopy was used to observe pinopodes on the surface of mid-secretory endometrial epithelium. Results: PR, LIF and osteopontin expression were all found to be weaker in secretory-phase stroma from adenomyosis patients than in healthy controls. HOXA10 expression was decreased in adenomyosis during the secretory phase, and also the proliferative phase, where it reached statistical significance in both epithelial and stromal compartments. Glycodelin and integrin β3 levels did not differ between diseased and healthy tissues in any of the cycle phases. Pinopodes were fewer and at later developmental stages in adenomyosis compared to those on the surface of healthy endometrium from the same time period of the menstrual cycle. Conclusions: Endometrium from adenomyosis patients is characterized by abnormal expression of various receptivity markers. The stromal compartment appears to be affected most, showing reduced expression of PR, LIF and osteopontin in the secretory phase and lower levels of HOXA10 during both proliferative and secretory phases. Decreased receptivity due to impaired stromal decidualization may contribute to poor reproductive outcomes in adenomyosis patients. Full article

Myokines released by exercise are identified as factors that can influence a person’s health and wellbeing. While myokine secretion in response to an acute bout of endurance and resistance-type exercise has been examined, the influence of resistance-exercise training on myokines at rest is less well established. Therefore, this study was designed to evaluate a panel of myokines at rest following a 12-week resistance-exercise training program in younger and older males. Participants (n = 15) completed a 12-week progressive resistance-exercise training program supervised by a certified fitness professional. The training protocol targeted all major muscle groups of the upper and lower body. Resting blood samples were collected before and after completion of the training program to determine concentrations of apelin, fibroblast growth factor-21 (FGF-21), interleukin (IL)-4, IL-6, IL-7, IL-15, leukemia inhibitory factor (LIF), and irisin. Two-way repeated ANOVAs were used to compare variables between time-points and age groups. There was a main effect of time found for apelin (p = 0.003) and IL-15 (p < 0.001), while no main effects for group or time were found for the other myokines (all p > 0.05). Age group × training status interactions were found for IL-6 (p = 0.04) and irisin (p = 0.014) without pairwise differences for IL-6 (p > 0.05), and younger males had higher concentrations of irisin compared to older males post-training (p = 0.036). Overall, the 12-week resistance-exercise training program significantly increased apelin and IL-15 over time but did not change the other resting myokine concentrations for the younger or older males. However, the higher concentration of irisin in younger versus older males post-training suggests a potential explanation for the anabolic resistance observed with aging. Full article

Bovine in vitro oocyte maturation (IVM) is an easy way to obtain oocytes for subsequent assisted reproductive techniques but is inefficient compared to in vivo maturation. Supplementation of three cytokines, fibroblast growth factor 2 (FGF2), leukemia inhibitory factor (LIF), and insulin-like growth factor 1 (IGF1), or FLI, has increased oocyte maturation and embryo development in multiple species, but studies have not explored the oocyte differences caused by FLI IVM supplementation. This study aimed to assess important nuclear and cytoplasmic maturation events in high-quality oocytes. FLI-supplemented oocytes had a decreased GV (3.0% vs. 13.7%, p < 0.01) and increased telophase I incidence (34.6% vs. 17.6%, p < 0.05) after IVM, increased normal meiotic spindles (68.8% vs. 50.0%, p < 0.001), and an increased nuclear maturation rate (75.1% vs. 66.8%, p < 0.001). Moreover, in metaphase II oocytes, the percentage of FLI-treated oocytes with a diffuse mitochondrial distribution was higher (87.7% vs. 77.5%, p < 0.05) and with a cortical mitochondrial distribution was lower (11.6% vs. 17.4%, p < 0.05). Additionally, FLI-supplemented oocytes had more pattern I cortical granules (21.3% vs. 14.4%, p < 0.05). These data suggest that FLI supplementation in bovine in vitro maturation medium coordinates nuclear and cytoplasmic maturation to produce higher-quality oocytes. Full article

This work explored whether supplementing selective members of the interleukin-6 (IL6) cytokine family during in vitro bovine oocyte maturation affects maturation success, cumulus–oocyte complex (COC) gene expression, fertilization success, and embryo development potential. Human recombinant proteins for IL6, IL11, and leukemia inhibitory factor (LIF) were supplemented to COCs during the maturation period, then fertilization and embryo culture commenced without further cytokine supplementation. The first study determined that none of these cytokines influenced the rate that oocytes achieved arrest at meiosis II. The second study identified that LIF and IL11 supplementation increases AREG transcript abundance. Supplementation with IL6 supplementation did not affect AREG abundance but reduced HAS2 transcript abundance. Several other transcriptional markers of oocyte competency were not affected by any of the cytokines. The third study determined that supplementing these cytokines during maturation did not influence fertilization success, but either LIF or IL11 supplementation increased blastocyst development. No effect of IL6 supplementation on subsequent blastocyst development was detected. The fourth experiment explored whether each cytokine treatment affects the post-thaw survivability of cryopreserved IVP blastocysts. None of the cytokines supplemented during oocyte maturation produced any positive effects on post-thaw blastocyst re-expansion and hatching. In conclusion, these outcomes implicate IL11 and LIF as potentially useful supplements for improving bovine oocyte competency. Full article