Ethylparaben induces apoptotic cell death in human placenta BeWo cells via the Caspase-3 pathway

Different isoforms of parabens into marine environment: Biological effects on the bacterium Aliivibrio fischeri and the marine mussel Mytilus galloprovincialis

Different isoforms of alkyl esters of p-Hydroxybenzoic acid, also known as parabens, are of great concern due to their widespread presence into the aquatic environment, their high concentrations in wastewater discharges, as well as their ability to induce adverse effects on aquatic organisms. Considering the imperative need for assessing their fate and risk to aquatic environment, the present study investigated the biological effects of two isoforms of parabens, methyl- (MeP) and propyl- (PrP), on the bacterium Aliivibrio fischeri (using the Bioluminescence Inhibition/Microtox® bioassay) and the mussel Mytilus galloprovincialis (in terms of mussel mortality, cellular, oxidative and genotoxic stress indices). The assessment of MeP and PrP behavior into aquatic media (artificial sea water/ASW and 2 % NaCl), primarily performed by UHPLC-UV-MS analysis, showed only a slight hydrolysis of PrP to 4-Hydrobenzoic acid (4-HBA). Furthermore, exposure of both species to different concentrations of each paraben revealed differences among their toxic potential, as well as their ability to cause cellular, oxidative and genotoxic effects on hemocytes of challenged mussels. Interestingly, the Microtox® bioassay showed that PrP mediated toxicity in A. fischeri were more pronounced than MeP, as revealed by the estimated toxic endpoints (in terms of concentration that promote 50 % of bioluminescence inhibition, EC50). Similarly, in challenged mussels, a significant disturbance of mussel hemocytes' lysosomal membrane integrity, as well as enhanced levels of superoxides, nitric oxides, lipid peroxidation byproducts, and micronuclei formation were observed. These findings are of great interest, since MeP and PrP differential toxic potential, as well their ability to induce pre-pathological alterations in marine species, like mussels, give new evidence for their risk to aquatic biota.

Comparative cytotoxicity induced by parabens and their halogenated byproducts in human and fish cell lines

Parabens are a group of para-hydroxybenzoic acid (p-HBA) esters widely used in pharmaceutical industries. Their safety is well documented in mammalian models, but little is known about their toxicity in non-mammal species. In addition, chlorinated and brominated parabens resulting from wastewater treatment have been identified in effluents. In the present study, we explored the cytotoxic effects (EC₅₀) of five parabens: methylparaben (MP), ethylparaben (EP), propylparaben (PP), butylparaben (BuP), and benzylparaben (BeP); the primary metabolite, 4-hydroxybenzoic acid (4-HBA), and three of the wastewater chlorinated/brominated byproducts on fish and human cell lines. In general, higher cytotoxicity was observed with increased paraben chain length. The tested compounds induced toxicity in the order of 4-HBA < MP < EP < PP < BuP < BeP. The halogenated byproducts led to higher toxicity with the addition of second chlorine. The longer chain-parabens (BuP and BeP) caused a concentration-dependent decrease in cell viability in fish cell lines. Intriguingly, the main paraben metabolite, 4-HBA, proved to be more toxic to fish hepatocytes than human hepatocytes by 100-fold. Our study demonstrated that the cytotoxicity of some of these compounds appears to be tissue-dependent. These observations provide valuable information for early cellular responses in human and non-mammalian models upon exposure to paraben congeners.

Mangifera Indica leaf extracts promote hair growth via activation of Wnt signaling pathway in human dermal papilla cells

The crosstalk between androgens and Wnt signaling pathways is critical in the hair growth cycle. Therefore, natural products that target these two pathways for the inhibition of hair loss are sought after. In this study, we investigated the effect of water extracts of Mangifera indica leaves (WEML) on hair growth. WEML treatment significantly reduced the expression levels of both dickkopf-1 (DKK1) and type 2 5α-reductase (SRD5A2) involved in Wnt signal suppression activity and dihydrotestosterone (DHT) synthesis, respectively, in human follicle dermal papilla cells (HFDP). In addition, WEML treatment effectively upregulated Wnt target genes and downregulated DKK1 expression that was increased by DHT treatment. Degranulation analysis in rat basophilic leukemia mast cell line (RBL-2H3) using β-hexosaminidase release assay confirmed that WEML did not exhibit allergenic activity. Furthermore, hair growth was significantly enhanced in in vivo mice model treated with WEML. These results suggest that M. indica leave extract contains bioactive materials that can be used to treat hair loss.

Antidepressants induce toxicity in human placental BeWo cells

Selective serotonin reuptake inhibitors (SSRIs), serotonin and noradrenaline reuptake inhibitors (SNRIs), and noradrenergic and specific serotonergic antidepressants (NaSSAs) are broadly used for the treatment of depression. Depression is one of the most common psychiatric disorders in pregnant women and SSRIs are commonly prescribed for depression during pregnancy. The placenta regulates the transport of nutrients and oxygen between the maternal and fetal circulation, and is essential for the survival and growth of the fetus. The present study investigated the effects of antidepressants on human placental BeWo cells. BeWo cell viability was significantly decreased following exposure to sertraline (SSRI), paroxetine (SSRI), fluvoxamine (SSRI), and duloxetine (SNRI), whereas escitalopram (SSRI), venlafaxine (SNRI), and mirtazapine (NaSSA) showed little or no effects. Extracellular lactate dehydrogenase activity was increased by sertraline, paroxetine, fluvoxamine, and duloxetine, indicating toxicity to the cells. Sertraline increased the production of cellular reactive oxygen species (ROS) and decreased the mitochondrial membrane potential. Sertraline decreased the cellular ATP content in a time and concentration-dependent manner. Caspase-3/7 activity and apoptotic cells, detected using the phosphatidylserine-specific fluorescent probe Apotracker Green, were increased by sertraline. Our findings suggest that antidepressants, such as sertraline, paroxetine, fluvoxamine, and duloxetine, induce toxicity in human placental BeWo cells. Sertraline may induce ROS-dependent apoptosis in human placental cells. These results are useful for further studies to determine the optimal dosage of antidepressants for pregnant women.

Butylparaben Induces the Neuronal Death Through the ER Stress-Mediated Apoptosis of Primary Cortical Neurons

Butylparaben is an organic compound that is used as an antimicrobial preservative in cosmetics and can cause neurotoxicity. However, whether butylparaben induces neuronal death is unclear. In this study, we report that butylparaben exposure induced neuronal apoptosis mediated by ER stress in primary cortical neurons. We found that butylparaben significantly inhibited the viability of primary cortical neurons and led to lactate dehydrogenase (LDH) release from primary cortical neurons. Upon exposure to butylparaben, primary cortical neurons exhibited increased levels of apoptosis-related proteins such as Cleaved-caspase3 and Bax. Interestingly, butylparaben-induced activation of apoptosis involved the upstream activation of ER stress proteins such as GRP78, CHOP, and ATF4. However, pharmacological inhibition of ER stress prevented the butylparaben-induced induction of apoptosis. Taken together, our findings suggest that butylparaben exposure activates the ER stress-mediated apoptosis of primary cortical neurons, which is closely linked with neurodegeneration in the brain. Therefore, targeting ER stress may be considered a strategy for the treatment of butylparaben-induced neurodegeneration.

Toxicity and removal of parabens from water: A critical review

Parabens are biocides used as preservatives in food, cosmetics and pharmaceuticals. They possess antibacterial and antifungal activity due to their ability to disrupt cell membrane and intracellular proteins, and cause changes in enzymatic activity of microbial cells. Water, one of our most valuable natural resource, has become a huge reservoir for parabens. Halogenated parabens from chlorination/ozonation of water contaminated with parabens have shown to be even more persistent in water than other types of parabens. Unfortunately, there is dearth of data on their (halogenated parabens) presence and fate in groundwater which serves as a major source of drinking water for a huge population in developing countries. An attempt to neglect the presence of parabens in water will expose man to it through ingestion of contaminated food and water. Although there are reviews on the occurrence, fate and behaviour of parabens in the environment, they largely omit toxicity and removal aspects. This review therefore, presents recent reports on the acute and chronic toxicity of parabens, their estrogenic agonistic and antagonistic activity and also their relationship with antimicrobial resistance. This article further X-rays several techniques that have been employed for the removal of parabens in water and their drawbacks including adsorption, biodegradation, membrane technology and advanced oxidation processes (AOPs). The heterogeneous photocatalytic process (one of the AOPs) appears to be more favoured for removal of parabens due to its ability to mineralize parabens in water. However, more work is needed to improve this ability of heterogeneous photocatalysts. Perspectives that will be relevant for future scientific studies and which will drive policy shift towards the presence of parabens in our drinking waters are also offered. It is hoped that this review will elicit some spontaneous actions from water professionals, scientists and policy makers alike that will provide more data, effective technologies, and adaptive policies that will address the growing threat of the presence of parabens in our environment with respect to human health.

Luteinizing hormone-like and follicle-stimulating hormone-like activities of equine chorionic gonadotropin β-subunit mutants in cells expressing rat luteinizing hormone/chorionic gonadotropin receptor and rat follicle-stimulating hormone receptor

To identify the specific region of eCG involved in FSH-like activity, the following mutant expression vectors were constructed targeting the amino acid residues 102–104 of the eCG β-subunit: single mutants, eCGβV102G/α, eCGβF103P/α, and eCGβR104K/α; double mutants, eCGβV102G;F103P/α, eCGβV102G;R104K/α, and eCGβF103P;R104K/α; triple mutant, eCGβV102G;F103P;R104K/α. The LH-like and FSH-like activities of eCG mutants were examined in CHO-K1 cells expressing rat LH/CG receptor and rat FSH receptor. The levels of eCGβV102G/α, eCGβR104K/α, and eCGβV102G;R104K/α in the culture supernatant were markedly lower than those of eCGβ/α-wt. The other mutants and rec-eCGβ/α-wt were efficiently secreted into the culture supernatant. The LH-like activities of eCGV104G/α, eCGβV102G;R104K/α, and eCGβF103P;R104K/α were approximately 61%, 52%, and 54%, respectively, of those of eCG-wt. The Rmax values of the mutants were 58.9%–78.8% those of eCG-wt with eCGβR104K/α exhibiting the lowest value. The FSH-like activities of single mutants were only 16%–20% of those of eCG-wt. Additionally, the FSH-like activity of double mutants was less than 10% of that of eCG-wt. In particular, the FSH-like activities of βV102G;R104K/α and βF103P;R104K/α were 2.5–2.9% of that of eCG-wt. These results suggest that the amino acid residues 102–104 of the eCG β-subunit are dispensable and that the residue 104 of the eCG β-subunit plays a pivotal role in signal transduction through the rat FSH receptor. Thus, these mutants may aid future studies on eCG interactions with mammalian FSH receptors in vitro and in vivo.

Physicochemical and biological similarity assessment of LBAL, a biosimilar to adalimumab reference product (Humira®)

LBAL was developed as an adalimumab (Humira®) biosimilar using Chinese hamster ovary cell lines. Comparable quality, safety, and efficacy between a biosimilar and its reference product should be ensured for regulatory approval. Here, we present the results of a comprehensive physicochemical and biological characterization between LBAL and Humira®. As physicochemical attributes, primary and higher-order structure, N-glycan profile, and disulfide linkage were investigated. Biological attributes were evaluated by target/receptor binding analysis and in vitro/ex vivo cell-based assays, which are linked to mechanisms of action. As a result, LBAL had the identical amino acid sequence, similar post-translational modifications and N-/C-terminal variants, and comparable primary, secondary, and tertiary structures and disulfide linkage profile. However, some differences in N-glycan profiles were observed. Biological activities, including tumor necrosis factor (TNF) binding, TNF-neutralization, apoptosis, Fc receptor binding, and complement-dependent cytotoxicity, were largely consistent. Despite a slightly lower antibody-dependent cellular cytotoxicity activity in LBAL, this difference was not significant under physiological conditions. As indicated, this extensive analytical characterization and functional comparison assessment showed that LBAL was similar to Humira®, with minor differences of no clinical relevance. Taken together, our comparative assessment of physicochemical and biological attributes demonstrated that LBAL is structurally and functionally very similar to Humira®, supporting the biosimilarity of clinical efficacy and safety.

Comparison of methods used for evaluation of mutagenicity/genotoxicity of model chemicals - parabens

Growing worldwide efforts to replace (reduce) animal testing and to improve alternative in vitro tests which may be more efficient in terms of both time, cost and scientific validity include also genotoxicity/mutagenicity endpoints. The aim of the review article was to summarize currently available in vitro testing approaches in this field, their regulatory acceptance and recommended combinations for classification of chemicals. A study using the combination of Comet Assay performed on two cell lines and the Chromosomal Aberration test on human peripheral lymphocytes was performed with the aim to predict the genotoxic potential of selected paraben esters, serving as a model chemical group. Parabens are widely used in consumer products as preservatives and have been reported to exhibit inconclusive results in numerous genotoxicity studies. The Comet Assay identified Ethylparaben and Benzylparaben as potentially genotoxic. The Chromosomal Aberration test revealed weak genotoxic potential in case of Ethylparaben and positive genotoxicity in case of Butylparaben, Propylparaben and Isopropylparaben. The main reasons for variability seem to be limited water solubility of parabens, determining their bioavailability at the cellular level, and absence of metabolic activation in the Comet Assay. The results confirmed that the Comet Assay should serve as a screening test and should not be used as a stand-alone method for classification of genotoxicity. The weight of evidence approach in risk assessment should be supported with data generated with the use of human relevant in vitro methods based on cells / tissues of human origin.