SACF and GILA assays on AML12 cells show limited predictive value for mouse liver genotoxicity.

Hepatocellular carcinoma (HCC) has been observed in neonatal mice following the integration of recombinant Adeno-Associated Viruses (rAAV) into the Rian locus. rAAV-related oncogenic risk for patients remains unclear, and the lack of relevant in vitro methods hinders its proper assessment. The soft agar colony-forming (SACF) assay and the growth in low attachment assay (GILA) monitor anchorage-independent growth, a hallmark of transformed adherent cells, and have been previously proposed to assess the tumorigenicity of CRISPR/Cas9-edited human MCF10A cells.

ApoE4 disrupts intracellular trafficking and iron homeostasis in a reproducible iPSC-based model of human brain endothelial cells.

Transferrin receptor in brain endothelial cells can deliver therapeutic antibodies to the brain via transcytosis across the blood-brain barrier (BBB). Whether receptor transport remains intact in Alzheimer disease is still a major open question. Here, we investigated whether apolipoprotein E4 (ApoE4), the major genetic risk factor for Alzheimer disease, altered intracellular transport in human brain endothelial cells.

Estimates of skin and blood concentrations of UV-filters: Insights from in vitro skin experiments.

Organic ultraviolet (UV) filters mitigate radiation transmission through the skin; however, uncertainties persist regarding their ability to cross the skin barrier and induce toxicity. Our aim was to use published in vitro skin permeation studies to predict UV-filter concentrations in blood and skin. In our review, we identified 35 papers reporting in vitro skin permeation of the 12 most used organic UV-filters.

Elucidation of B-cell specific drug immunogenicity liabilities via a novel assay.

The advent of large molecule therapeutics has revolutionized treatment options for previously unmet medical needs. This advent has also led to an increased impact of immunogenicity on drug efficacy and safety. In order to maximize the potential of large molecule therapeutics, immunogenicity-related liabilities must be identified as early in development as possible, using an integrated risk assessment that takes into account the various cell types and processes involved.

Synthesis and Multidisciplinary Preclinical Investigations of Ferrocenyl, Ruthenocenyl, and Benzyl Derivatives of Thiabendazole as New Drug Candidates against Soil-Transmitted Helminth Infections.

An estimated 1.5 billion people worldwide are infected with at least one parasitic nematode species classified as soil-transmitted helminths (STHs). The recommended control strategy is to reduce morbidity using a single oral dose of the benzimidazole drugs, albendazole and mebendazole.

A BioID-based approach uncovers the interactome of hexose-6-phosphate dehydrogenase in breast cancer cells and identifies anterior gradient protein 2 as an interacting partner.

Background: Hexose-6-phosphate dehydrogenase (H6PD) catalyzes the first two steps of the pentose-phosphate-pathway (PPP) within the endoplasmic reticulum, generating NADPH. H6PD modulates essential physiological processes, including energy and redox metabolism. Its sole reported interacting partner is 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1), utilizing NADPH to reactivate glucocorticoids, linking energy status with hormonal response.

Discovery of non-steroidal aldo-keto reductase 1D1 inhibitors through automated screening and in vitro evaluation.

Steroid hormones regulate a wide range of physiological processes in the human body. However, exposure to xenobiotics can disrupt the hormonal balance by inhibition of enzymes involved in hormone synthesis or metabolism. Aldo-keto reductase 1D1 (AKR1D1) plays a key role in bile acid and steroid hormone metabolism by catalyzing the reduction of the double bond between C4 and C5 atoms of Δ(4)-steroids.

The long way from raw data to NAM-based information: Overview on data layers and processing steps.

Toxicological test methods generate raw data and provide instructions on how to use these to determine a final outcome such as a classification of test compounds as hits or non-hits. The data processing pipeline provided in the test method description is often highly complex. Usually, multiple layers of data, ranging from a machine-generated output to the final hit definition, are considered.

Advanced tissue technologies of blood-brain barrier organoids as high throughput toxicity readouts in drug development.

Recent advancements in engineering Complex models (CIVMs) such as Blood-brain barrier (BBB) organoids offer promising platforms for preclinical drug testing. However, their application in drug development, and especially for the regulatory purposes of toxicity assessment, requires robust and reproducible techniques. Here, we developed an adapted set of orthogonal image-based tissue methods including hematoxylin and eosin staining (HE), immunohistochemistry (IHC), multiplex immunofluorescence (mIF), and Matrix Assisted Laser Desorption/Ionization Mass Spectrometry Imaging (MALDI-MSI) to validate CIVMs for drug toxicity assessments.

Disruption of serotonin homeostasis in intestinal organoids provides insights into drug-induced gastrointestinal toxicity.

Drug-induced gastrointestinal toxicity is a frequent clinical adverse event that needs to be carefully monitored and managed to ensure patient compliance. While preclinical assessment of drug-induced gastrointestinal toxicity mostly relies on animal experimentation, intestinal organoids have gained increasing attention to identify gastrointestinal toxicants in vitro. Nonetheless, current in vitro protocols primarily assess structural alterations induced by drugs, whereas gastrointestinal adverse events can often stem from functional disturbances.

Potential antiandrogenic effects of parabens and benzophenone-type UV-filters by inhibition of 3α-hydroxysteroid dehydrogenases.

Parabens and UV-filters are frequently used additives in cosmetics and body care products that prolong shelf-life. They are assessed for potential endocrine disrupting properties. Antiandrogenic effects of parabens and benzophenone-type UV-filters by blocking androgen receptor (AR) activity have been reported.

Assessment of the potential risk of oteseconazole and two other tetrazole antifungals to inhibit adrenal steroidogenesis and peripheral metabolism of corticosteroids.

The triazole antifungals posaconazole and itraconazole can cause pseudohyperaldosteronism with hypertension and hypokalemia, edema, and gynecomastia by inhibiting steroid synthesis and metabolism. Mechanisms underlying pseudohyperaldosteronism include inhibition of adrenal 11β-hydroxylase cytochrome-P450 (CYP) 11B1 and 17α-hydroxylase (CYP17A1) as well as peripherally expressed 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). To enhance specificity for fungal CYP51, tetrazoles have been developed.

In silico and in vitro assessment of drugs potentially causing adverse effects by inhibiting CYP17A1.

Cytochrome P450 enzymes (CYPs) play a crucial role in the metabolism and synthesis of various compound classes. While drug-metabolizing CYP enzymes are frequently investigated as anti-targets, the inhibition of CYP enzymes involved in adrenal steroidogenesis is not well studied. The steroidogenic enzyme CYP17A1 is a dual-function enzyme catalyzing hydroxylase and lyase reactions relevant for the biosynthesis of adrenal glucocorticoids and androgens.

Metabolic outcomes in obese mice undergoing one-anastomosis gastric bypass (OAGB) with a long or a short biliopancreatic limb.

One-anastomosis gastric bypass (OAGB) has gained importance as a simple, safe, and effective operation to treat morbid obesity. We previously found that Roux-en-Y gastric bypass surgery with a long compared with a short biliopancreatic limb (BPL) leads to improved weight loss and glucose tolerance in obese mice. However, it is not known whether a long BPL in OAGB surgery also results in beneficial metabolic outcomes.

Mechanisms of hepatocellular toxicity associated with the components of St. John's Wort extract hypericin and hyperforin in HepG2 and HepaRG cells.

St. John's Wort preparations are used for the treatment of mild to moderate depression. They are usually well tolerated but can cause adverse reactions including liver toxicity in rare cases.

In vitro methods to assess 11β-hydroxysteroid dehydrogenase type 2 activity.

11β-Hydroxysteroid dehydrogenase type 2 (11β-HSD2) converts active 11β-hydroxyglucocorticoids to their inactive 11-keto forms, fine-tuning the activation of mineralocorticoid and glucocorticoid receptors. 11β-HSD2 is expressed in mineralocorticoid target tissues such as renal distal tubules and cortical collecting ducts, and distal colon, but also in placenta where it acts as a barrier to reduce the amount of maternal glucocorticoids that reach the fetus. Disruption of 11β-HSD2 activity by genetic defects or inhibitors causes the syndrome of apparent mineralocorticoid excess (AME), characterized by hypernatremia, hypokalemia and hypertension.

In vitro methods to assess 11β-hydroxysteroid dehydrogenase type 1 activity.

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inactive 11-keto-glucocorticoids to their active 11β-hydroxylated forms. It also catalyzes the oxoreduction of other endogenous and exogenous substrates. The ubiquitously expressed 11β-HSD1 shows high levels in liver and other metabolically active tissues such as brain and adipose tissue.

A battery of in silico models application for pesticides exerting reproductive health effects: Assessment of performance and prioritization of mechanistic studies.

Given the high attention to endocrine disrupting chemicals (EDC), there is an urgent need for the development of rapid and reliable approaches for the screening of large numbers of chemicals with respect to their endocrine disruption potential. This study aimed at the assessment of the correlation between the predicted results of a battery of in silico tools and the reported observed adverse effects from in vivo reproductive toxicity studies. We used VirtualToxLab (VTL) software and the EndocrineDisruptome (ED) online tool to evaluate the binding affinities to nuclear receptors of 17 pesticides, 7 of which were classified as reprotoxic substances under Regulation (EC) No 1272/2008 on the classification, labelling and packaging of substances and mixtures (CLP).

Identification of a human blood biomarker of pharmacological 11β-hydroxysteroid dehydrogenase 1 inhibition.

Background And Purpose: 11β-Hydroxysteroid dehydrogenase-1 (11β-HSD1) catalyses the oxoreduction of cortisone to cortisol, amplifying levels of active glucocorticoids. It is a pharmaceutical target in metabolic disease and cognitive impairments. 11β-HSD1 also converts some 7oxo-steroids to their 7β-hydroxy forms.

Characterization of the interferences of systemic azole antifungal drugs with adrenal steroid biosynthesis using H295R cells and enzyme activity assays.

Azole antifungals, designed to inhibit fungal CYP51, have a liability to inhibit human CYP enzymes. Whilst drug-metabolizing CYPs are covered in preclinical safety assessment, those metabolizing endogenous bioactive molecules are usually not. Posaconazole and itraconazole were recently found to cause pseudohyperaldosteronism with hypokalemia and hypertension by inhibiting CYP11B1-dependent adrenal cortisol biosynthesis.

Virtual screening and biological evaluation to identify pharmaceuticals potentially causing hypertension and hypokalemia by inhibiting steroid 11β-hydroxylase.

Several drugs were found after their market approval to unexpectedly inhibit adrenal 11β-hydroxylase (CYP11B1)-dependent cortisol synthesis. Known side-effects of CYP11B1 inhibition include hypertension and hypokalemia, due to a feedback activation of adrenal steroidogenesis, leading to supraphysiological concentrations of 11-deoxycortisol and 11-deoxycorticosterone that can activate the mineralocorticoid receptor. This results in potassium excretion and sodium and water retention, ultimately causing hypertension.

Assessment of the inhibitory potential of anabolic steroids towards human AKR1D1 by computational methods and in vitro evaluation.

Exposure to xenobiotics can adversely affect biochemical reactions, including hepatic bile acid synthesis. Bile acids are essential for dissolving lipophilic compounds in the hydrophilic environment of the gastrointestinal tract. The critical micellar concentration of bile acids depends on the Δ4-reduction stereochemistry, with the 3-oxo-5β-steroid-Δ4-dehydrogenase (AKR1D1) introducing the cis ring A/B conformation.

ER-mitochondria contacts and cholesterol metabolism are disrupted by disease-associated tau protein.

Abnormal tau protein impairs mitochondrial function, including transport, dynamics, and bioenergetics. Mitochondria interact with the endoplasmic reticulum (ER) via mitochondria-associated ER membranes (MAMs), which coordinate and modulate many cellular functions, including mitochondrial cholesterol metabolism. Here, we show that abnormal tau loosens the association between the ER and mitochondria in vivo and in vitro.