Prolonged cadmium exposure alters benign uterine fibroid cell behavior, extracellular matrix components, and TGFB signaling

TGF-β/SMAD Pathway Mediates Cadmium Poisoning-Induced Chicken Liver Fibrosis and Epithelial-Mesenchymal Transition

Cadmium(Cd) is a toxic heavy metal widely present in the environment, capable of accumulating in the liver and causing liver damage. In this study, the mechanism of cadmium-induced liver fibrosis in chickens was investigated from the perspective of hepatocyte epithelial-mesenchymal transition (EMT) based on the establishment of a model of chicken cadmium toxicity and a model of cadmium-stained cells in a chicken hepatocellular carcinoma cell line (LMH). The 7-day-old chickens were randomly divided into the regular group (C group) and cadmium poisoning group (Cd group), and the entire test cycle was 60 days. Three sampling time points of 20 days, 40 days, and 60 days were established. By testing the liver coefficient, histopathological and ultrastructural changes in chicken livers were observed. The enzyme activities of liver function and the expression changes of fibrosis markers (COL1A1, Fibronectin), epithelial-mesenchymal transition markers (E-cadherin, Vimentin, and α-SMA), and the critical factors of the TGF-β/SMAD signaling pathway (TGF-β1, SMAD 2, and SMAD 3) were detected in the liver expression changes. The results showed that at the same sampling time point, the chicken liver coefficient in group Cd was significantly higher than that in control group (P < 0.01); the activities of the liver function enzymes ALT and AST in chickens in the Cd group were significantly higher than those in the C group (P < 0.01); liver hepatocytes degenerated and necrotic, the number of erythrocytes in the blood vessels was increased, and inflammatory cells infiltrated in the sinusoidal gap; the perisinusoidal gap of the liver was enlarged, and there was an apparent aggregation of collagen fibers in the intervening period as seen by transmission electron microscopy. The results of Masson staining showed that the percentage of fiber area was significantly higher in the chickens' livers of the Cd group. The fiber area percentage was significantly higher. The results of real-time fluorescence quantitative PCR and Western Blot showed that the expression of E-cadherin in the livers of chickens in the Cd group was significantly lower than that in the C group (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-β1, SMAD 2, and SMAD 3 was significantly higher than that in the C group (P < 0.01). The results of in vitro assays showed that in the LMH cell model established by adding trimethylamine N-oxide, an activator of the TGF-β/SMAD signaling pathway, and oxidized picric acid, an inhibitor of the TGF-β/SMAD signaling pathway, the expression of E-cadherin was significantly reduced in cadmium-stained LMH cells (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-β, SMAD 2, and SMAD 3 was significantly elevated (P < 0.01). Cadmium and Trimethylamine N-oxide, an activator of the TGF-β/SMAD signaling pathway, promoted the expression of these factors. In contrast, the inhibitor of the TGF-β/SMAD signaling pathway, Oxymatrine, a TGF-β/SMAD signaling pathway inhibitor, significantly slowed down these changes. These results suggest that cadmium induces hepatic epithelial-mesenchymal transition by activating the TGF-β/SMAD signaling pathway in chicken hepatocytes, promoting hepatic fibrosis.

Transcriptomic and behavioral analyses reveal unique target tissues and molecular pathways associated with embryonic exposure to low level glyphosate and metal mixtures in zebrafish

Investigation of developmental molecular events following exposure to environmentally relevant agrochemical mixtures is critical to predicting their potential long-term ecological and human health risks. Here, we sought to uncover transcriptomic changes during zebrafish (Danio rerio) embryonic development following exposure to glyphosate and co-exposure to metals. Glyphosate is widely used globally with an allowable drinking water limit of 700 ppb. We examined effects of glyphosate (10 ppb) alone and when co-exposed to a metal mixture containing low levels of arsenic (4 ppb), lead (5 ppb), cadmium (2 ppb), and vanadium (15 ppb). This mixture was derived based on behavioral and morphological toxicity findings and environmentally relevant concentrations found in agricultural regions where glyphosate and metals are ubiquitously present. Gene expression patterns coupled to a single-cell transcriptomic dataset revealed that developmental exposure (28-72 h post fertilization) to glyphosate dysregulates expression of developmental genes specific to the central nervous system. Subsequent studies indicated significant suppression of larval zebrafish movement with 10 ppb glyphosate exposure. Studies with glyphosate + metals mixture and metals mixture alone showed unique developmental transcriptomic patterns and behavioral changes compared to glyphosate exposure alone. However, some outcomes (e.g., changes in expression of genes involved in epigenetic regulation and extracellular matrix patterning) were common across all three exposures compared to the control. Notably, glyphosate + metals co-exposure distinctly suppresses lysosomal transcripts and targets renal developmental genes. While further studies are required to uncover the precise nature of the interactions between glyphosate and metals, our study shows that glyphosate at very low levels is a behavioral and neurotoxicant that changes when metals are present. Given this herbicide affects distinctive physiological processes, including renal development and lysosomal dysregulation when co-exposed with metals, we conclude that environmental cation levels should be considered in glyphosate toxicity and risk assessment.

The adverse role of endocrine disrupting chemicals in the reproductive system

Reproductive system diseases pose prominent threats to human physical and mental well-being. Besides being influenced by genetic material regulation and changes in lifestyle, the occurrence of these diseases is closely connected to exposure to harmful substances in the environment. Endocrine disrupting chemicals (EDCs), characterized by hormone-like effects, have a wide range of influences on the reproductive system. EDCs are ubiquitous in the natural environment and are present in a wide range of industrial and everyday products. Currently, thousands of chemicals have been reported to exhibit endocrine effects, and this number is likely to increase as the testing for potential EDCs has not been consistently required, and obtaining data has been limited, partly due to the long latency of many diseases. The ability to avoid exposure to EDCs, especially those of artificially synthesized origin, is increasingly challenging. While EDCs can be divided into persistent and non-persistent depending on their degree of degradation, due to the recent uptick in research studies in this area, we have chosen to focus on the research pertaining to the detrimental effects on reproductive health of exposure to several EDCs that are widely encountered in daily life over the past six years, specifically bisphenol A (BPA), phthalates (PAEs), polychlorinated biphenyls (PCBs), parabens, pesticides, heavy metals, and so on. By focusing on the impact of EDCs on the hypothalamic-pituitary-gonadal (HPG) axis, which leads to the occurrence and development of reproductive system diseases, this review aims to provide new insights into the molecular mechanisms of EDCs' damage to human health and to encourage further in-depth research to clarify the potentially harmful effects of EDC exposure through various other mechanisms. Ultimately, it offers a scientific basis to enhance EDCs risk management, an endeavor of significant scientific and societal importance for safeguarding reproductive health.

Chronic PFOA exposure in vitro causes acquisition of multiple tumor cell characteristics in rat liver cells

Perfluorooctanoic acid (PFOA) is tumorigenic in rats and mice and potentially tumorigenic in humans. Here, we studied long-term PFOA exposure with an in vitro transformation model using the rat liver epithelial cell, TRL 1215. Cells were cultured in 10 μM (T10), 50 μM (T50) and 100 μM (T100) PFOA for 38 weeks and compared to passage-matched control cells. T100 cells showed morphological changes, loss of cell contact inhibition, formation of multinucleated giant and spindle-shaped cells. T10, T50, and T100 cells showed increased LC50 values 20%, 29% to 35% above control with acute PFOA treatment, indicating a resistance to PFOA toxicity. PFOA-treated cells showed increases in Matrix metalloproteinase-9 secretion, cell migration, and developed more and larger colonies in soft agar. Microarray data showed Myc pathway activation at T50 and T100, associating Myc upregulation with PFOA-induced morphological transformation. Western blot confirmed that PFOA produced significant increases in c-MYC protein expression in a time- and concentration-related manner. Tumor invasion indicators MMP-2 and MMP-9, cell cycle regulator cyclin D1, and oxidative stress protein GST were all significantly overexpressed in T100 cells. Taken together, chronic in vitro PFOA exposure produced multiple cell characteristics of malignant progression and differential gene expression changes suggestive of rat liver cell transformation.

Update on the Role and Regulatory Mechanism of Extracellular Matrix in the Pathogenesis of Uterine Fibroids

Uterine fibroids (UFs), also known as leiomyomas, are benign tumors of the myometrium affecting over 70% of women worldwide, particularly women of color. Although benign, UFs are associated with significant morbidity; they are the primary indication for hysterectomy and a major source of gynecologic and reproductive dysfunction, ranging from menorrhagia and pelvic pain to infertility, recurrent miscarriage, and preterm labor. So far, the molecular mechanisms underlying the pathogenesis of UFs are still quite limited. A knowledge gap needs to be filled to help develop novel strategies that will ultimately facilitate the development of therapies and improve UF patient outcomes. Excessive ECM accumulation and aberrant remodeling are crucial for fibrotic diseases and excessive ECM deposition is the central characteristics of UFs. This review summarizes the recent progress of ascertaining the biological functions and regulatory mechanisms in UFs, from the perspective of factors regulating ECM production, ECM-mediated signaling, and pharmacological drugs targeting ECM accumulation. In addition, we provide the current state of knowledge by discussing the molecular mechanisms underlying the regulation and emerging role of the extracellular matrix in the pathogenesis of UFs and in applications. Comprehensive and deeper insights into ECM-mediated alterations and interactions in cellular events will help develop novel strategies to treat patients with this common tumor.

Prolonged Cadmium Exposure Alters Migration Dynamics and Increases Heterogeneity of Human Uterine Fibroid Cells—Insights from Time Lapse Analysis

Cadmium (Cd) is one of the most prevalent environmental heavy metal contaminants and is considered an endocrine disruptor and carcinogen. In women with uterine fibroids, there is a correlation between blood Cd levels and fibroid tumor size. In this study, fibroid cells were exposed to 10 µM CdCl2 for 6 months and a fast-growing Cd-Resistant Leiomyoma culture, termed CR-LM6, was recovered. To characterize the morphological and mechanodynamic features of uterine fibroid cells associated with prolonged Cd exposure, we conducted time lapse imaging using a Zeiss confocal microscope and analyzed data by Imaris and RStudio. Our experiments recorded more than 64,000 trackable nuclear surface objects, with each having multiple parameters such as nuclear size and shape, speed, location, orientation, track length, and track straightness. Quantitative analysis revealed that prolonged Cd exposure significantly altered cell migration behavior, such as increased track length and reduced track straightness. Cd exposure also significantly increased the heterogeneity in nuclear size. Additionally, Cd significantly increased the median and variance of instantaneous speed, indicating that Cd exposure results in higher speed and greater variation in motility. Profiling of mRNA by NanoString analysis and Ingenuity Pathway Analysis (IPA) strongly suggested that the direction of gene expression changes due to Cd exposure enhanced cell movement and invasion. The altered expression of extracellular matrix (ECM) genes such as collagens, matrix metallopeptidases (MMPs), secreted phosphoprotein 1 (SPP1), which are important for migration contact guidance, may be responsible for the greater heterogeneity. The significantly increased heterogeneity of nuclear size, speed, and altered migration patterns may be a prerequisite for fibroid cells to attain characteristics favorable for cancer progression, invasion, and metastasis.

Uncovering Evidence: Associations between Environmental Contaminants and Disparities in Women's Health

Over the years, industrial accidents and military actions have led to unintentional, large-scale, high-dose human exposure to environmental contaminants with endocrine-disrupting action. These historical events, in addition to laboratory studies, suggest that exposure to toxicants such as dioxins and polychlorinated biphenyls negatively impact the reproductive system and likely influence the development of gynecologic diseases. Although high-level exposure to a single toxicant is rare, humans living in industrialized countries are continuously exposed to a complex mixture of manmade and naturally produced endocrine disruptors, including persistent organic pollutants and heavy metals. Since minorities are more likely to live in areas with known environmental contamination; herein, we conducted a literature review to identify potential associations between toxicant exposure and racial disparities in women's health. Evidence within the literature suggests that the body burden of environmental contaminants, especially in combination with inherent genetic variations, likely contributes to previously observed racial disparities in women's health conditions such as breast cancer, endometriosis, polycystic ovarian syndrome, uterine fibroids, and premature birth.

Follistatin-Like-1 (FSTL1) Is a Fibroblast-Derived Growth Factor That Contributes to Progression of Chronic Kidney Disease

Our understanding of the mechanisms responsible for the progression of chronic kidney disease (CKD) is incomplete. Microarray analysis of kidneys at 4 and 7 weeks of age in Col4a3^-/- mice, a model of progressive nephropathy characterized by proteinuria, interstitial fibrosis, and inflammation, revealed that Follistatin-like-1 (Fstl1) was one of only four genes significantly overexpressed at 4 weeks of age. mRNA levels for the Fstl1 receptors, Tlr4 and Dip2a, increased in both Col4a^-/- mice and mice subjected to unilateral ureteral obstruction (UUO). RNAscope^® (Advanced Cell Diagnostics, Newark CA, USA) localized Fstl1 to interstitial cells, and in silico analysis of single cell transcriptomic data from human kidneys showed Fstl1 confined to interstitial fibroblasts/myofibroblasts. In vitro, FSTL1 activated AP1 and NFκB, increased collagen I (COL1A1) and interleukin-6 (IL6) expression, and induced apoptosis in cultured kidney cells. FSTL1 expression in the NEPTUNE cohort of humans with focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN), and IgA nephropathy (IgAN) was positively associated with age, eGFR, and proteinuria by multiple linear regression, as well as with interstitial fibrosis and tubular atrophy. Clinical disease progression, defined as dialysis or a 40 percent reduction in eGFR, was greater in patients with high baseline FSTL1 mRNA levels. FSTL1 is a fibroblast-derived cytokine linked to the progression of experimental and clinical CKD.

Prolonged cadmium exposure alters benign uterine fibroid cell behavior, extracellular matrix components, and TGFB signaling

The heavy metal Cadmium (Cd), a widespread environmental contaminant, poses serious hazards to human health and is considered a metallohormone and carcinogen. In women with uterine fibroids, there is a significant association between blood Cd levels and increased fibroid tumor size. The aim of this study was to determine if benign human uterine leiomyoma (fibroid) cells could be malignantly transformed in vitro by continuous Cd exposure and, if so, explore a molecular mechanism by which this could occur. We found when fibroid cells were exposed to 10 µM CdCl₂ for 8 weeks, a robust and fast‐growing Cd‐Resistant Leiomyoma (CR‐LM) cell culture was established. The CR‐LM cells formed viable colonies in soft agar and had increased cytoplasmic glycogen aggregates, enhanced cell motility, a higher percentage of cells in G2/M phase, and increased expression of the proliferation marker Ki‐67. NanoString analysis showed downregulation of genes encoding for extracellular matrix (ECM) components, such as collagens, fibronectins, laminins, and SLRP family proteins, whereas genes involved in ECM degradation (MMP1, MMP3, and MMP10) were significantly upregulated. A volcano plot showed that the top differentially genes favored cancer progression. Functional analysis by ingenuity pathway analysis predicted a significant inhibition of TGFB1 signaling, leading to enhanced proliferation and attenuated fibrosis. Prolonged Cd exposure altered phenotypic characteristics and dysregulated genes in fibroid cells predicative of progression towards a cancer phenotype. Therefore, continuous Cd exposure alters the benign characteristics of fibroid cells in vitro, and Cd exposure could possibly pose a health hazard for women with uterine fibroids.